462 results on '"Ahmad V"'
Search Results
2. Systemic analysis of soil microbiome deciphers anthropogenic influence on soil ecology and ecosystem functioning
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Gupta, S., Kumar, M., Kumar, J., Ahmad, V., Pandey, R., and Chauhan, N. S.
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- 2017
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3. An overview of Indonesian doctors in combating COVID-19
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Yudanto, Ahmad V., primary, Ulfa, Maria, additional, Wening, Dayu L., additional, and Azuma, Momoyo, additional
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- 2022
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4. Presentation of knowledge sharing model in Bank Maskan Iran
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Maryam Firoozi, ahmad vedadi, and alireza Amirkabiri
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knowledge sharing ,knowledge management ,knowledge fit ,social networks ,knowledge development ,Business ,HF5001-6182 - Abstract
Abstract The purpose of this research is to present the knowledge sharing model in Maskan Bank of Iran. The research method is applicable in term of its purpose, and mixed in terms of implementation. The statistical population in the qualitative part includes 15 experts, professors, and all people who have had practical or research activities in the field of knowledge sharing, using a purposive sampling method; and in the quantitative part, it includes 344 employees of the headquarters of Maskan Bank of Tehran, using a simple random sampling method. Data collection was done in the qualitative part by using semi-structured interviews; and in the quantitative part by a researcher-made questionnaire. The data-based method was used in the analysis of the data of the qualitative part, and PLS software in the quantitative. The results in the qualitative part showed that 6 structures include: causal conditions (with 3 dimensions of universality and inevitability, the need to change the attitude towards branding, urban brand identity), contextual conditions (with 3 dimensions of brand structural coherence, urban branding, strategic location of city), intervening conditions (with 3 dimensions of tourist behavior pattern, investment/financing, environmental factors), dimensions of the phenomenon (with 3 dimensions of creating a platform for smart tourism, attention to stakeholders, integrated urban brand management), strategies (with 3 dimensions of urban advertising system improvement, smart urban branding design, urban brand culture), and consequences (with 3 dimensions of social capital development, development of quality of life, competitive power of urban brand). Based on the results of quantitative analysis, the relationships between significant research variables and the model have a good fit. Extended Abstract Introduction During many years and working in organizations, human resources acquire sets of ideas, thoughts, skills, experiences and applicable sciences. The collection of such reserves is considered the knowledge of each person, which is recorded in the person's mind over time. As long as this knowledge exists in a person's mind, other people do not have the ability to access and benefit from it. There are many organizations that have such people (Park & Gabbard, 2018). Leibovitz believes that knowledge management is a combination of acquisition and storage of obvious knowledge, along with intellectual capital management. In other words, knowledge management is the process through which organizations use their collected information. Approaches to knowledge management depend on the management perspective. Differences can be caused by information-based, technology-based, and culture-based perspectives (Asgharneghad & Haghdoust, 2022). Therefore, one of the most important means of continuous creation of knowledge is sharing it among all units and members of the organization with an emphasis on technology and social interaction, attention to which has an important role in the survival of the organization in the spaces facing the competitive organization (Gholipour domyeh, 2023). Knowledge sharing is the axis of development and transformation in different societies and it is considered the main focus of training specialized and trained human resources in any society. Realization of knowledge management, sharing and documenting it in financial and banking organizations is one of the basic needs of today's knowledge-oriented society. In the current age, which is called the age of knowledge, organizations are witnessing environments that are becoming more dynamic and challenging day by day, and consider intangible and spiritual capital, called knowledge, as an important and vital factor (Firouzi & Feyzi, 2017). Based on the said material, the researcher is trying to answer the question: what is the model of knowledge sharing in Iran Maskan Bank? Theoretical Framework Sharing knowledge Researchers state that one of the key assets of organizations is the knowledge they have access to (Hao et al, 2019). Knowledge sharing is the voluntary and enthusiastic transfer of acquired skills and experiences to other people and departments of the organization (Gupta et al, 2019). Knowledge sharing is also defined as informational behavior that requires effort and preparation to be responsive and understand information knowledge sharing (Kurmiawan at al, 2020). Knowledge sharing takes place voluntarily to share their expertise and knowledge with others with the intention of creating an interested learning process (Oyemomi et al, 2019). Hemti Nooddoost Gilani & Bagherzadeh (2023) investigated the relationship between intellectual capital and creativity with the mediating role of knowledge sharing perception in Sanat and Ma'dan Bank. The findings of the research indicated the existence of a positive and significant relationship between intellectual capital and creativity of employees in Sanat and Ma'dan Bank. Also, the mediating role of the perception variable of knowledge sharing in the relationship between the components of intellectual capital and creativity was confirmed. These findings mean that the emphasis on knowledge sharing by employees can have a positive effect on the creativity of employees in a way that significantly influences the effectiveness of intellectual capital on the creativity of employees. Gholipour domyeh (2023) investigated the simultaneous optimization of knowledge sharing and customer loyalty in social networks under the digital marketing approach. The results of the integrated approach on a company active in the field of digital marketing in Tehran showed that there is a significant positive effect of 6.47% between customer loyalty and knowledge sharing at a significance level of 1%. The results of the regression analysis also showed that there is a positive and significant relationship between knowledge sharing and customer loyalty under the digital marketing approach by 1.53%. AHP analysis showed that protestive behavior and purchase intention are the most important components of customer loyalty. Coding and implementation of the proposed bi-objective mathematical model in Games software provided a level of optimization in which maximum shared knowledge with maximum customer loyalty was achieved. Research methodology The research method is applicable in term of its purpose, and mixed in terms of implementation. The statistical population in the qualitative part includes 15 experts, professors, and all people who have had practical or research activities in the field of knowledge sharing, using a purposive sampling method; and in the quantitative part, it includes 344 employees of the headquarters of Maskan Bank of Tehran, using a simple random sampling method. Data collection was done in the qualitative part by using semi-structured interviews; and in the quantitative part by a researcher-made questionnaire. Research findings The data-based method was used in the analysis of the data of the qualitative part, and PLS software in the quantitative. The results in the qualitative part showed that 6 structures include: causal conditions (with 3 dimensions of universality and inevitability, the need to change the attitude towards branding, urban brand identity), contextual conditions (with 3 dimensions of brand structural coherence, urban branding, strategic location of city), intervening conditions (with 3 dimensions of tourist behavior pattern, investment/financing, environmental factors), dimensions of the phenomenon (with 3 dimensions of creating a platform for smart tourism, attention to stakeholders, integrated urban brand management), strategies (with 3 dimensions of urban advertising system improvement, smart urban branding design, urban brand culture), and consequences (with 3 dimensions of social capital development, development of quality of life, competitive power of urban brand). Conclusion The current research was conducted with the aim of presenting a knowledge sharing model in Iran Housing Bank. The results of this research are in agreement with the results of Hemti Nooddoost Gilani & Bagherzadeh (2023), Gholipour domyeh (2023), Azeem et al, (2021), Bayati et al, (2021), Ghanbari & Ahmadi (2022), Tabatabaei et al, (2020), Katlijn et al, (2021), Daphna et al, (2020), and Lee et al, (2020). Katlijn et al, (2021) in their study showed that people believe that their knowledge is an important part of their identity; sharing it is costly, but facilitates greater trust that the recipients of this knowledge have with future reciprocal rewards. According to the results of this research, the following suggestions are presented: Create a culture of knowledge sharing: managers should create a culture that encourages employees to share their knowledge and experiences. This can be through team meetings, internal publications, online systems, or collaboration platforms. Creating an atmosphere of cooperation: encouraging employees to cooperate and interact with each other is important. Banks can promote co-working spaces, hybrid teams, and joint projects so that employees can directly communicate with each other and share their knowledge. Internal training platforms: creating an internal training platform where employees can easily access training resources, recorded trainings, and online courses will help companies to share their knowledge with bank employees.
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- 2024
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5. Ratcheting Response of Heat-Treated Notched 1045 Steel Samples Undergoing Asymmetric Uniaxial Loading Cycles
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Faezeh Hatami and Ahmad Varvani-Farahani
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local ratcheting at notch root ,heat treatment conditions ,kinematic hardening rules ,backstress increments ,asymmetric loading cycles ,Engineering (General). Civil engineering (General) ,TA1-2040 - Abstract
The present study evaluates the ratcheting response of notched cylindrical samples made of 1045 steel alloy subjected to asymmetric loading cycles using the kinematic hardening framework, coupled with Neuber’s rule. Test samples with V-shaped and semi-circular edge notches were first heat-treated under different conditions, resulting in various material hardness values at the notch root region. Local ratcheting at the notch root of samples was found to be highly dependent on the notch shape and the heat treatment conditions. HT1 samples with a lower hardness of 12 RC at the notch region possessed higher values of ratcheting, while ratcheting at the notched region for HT2 samples with 40 RC dropped to half of that in HT1 samples. The higher hardness of 50 RC at the notch edge of HT3 samples promoted the initial yield strength and the yield surface through the kinematic hardening rule with a larger translation into the deviatoric stress space as compared with samples HT1 and HT2 with 12 and 40 RC, respectively. The local ratcheting strain in sample HT1, with semi-circular notches (Kt=1.65) at a stress ratio (Smax/Sult) of 0.965, remained below 1.80% during the first hundred loading cycles. The local ratcheting decreased to 1.2% for sample HT2 and further dropped to 0.9% for sample HT3. The yield surfaces were translated consistent with the magnitude and direction of the backstress increments, as the applied loading excursion exceeded the elastic limit. Through the use of the Ahmadzadeh–Varvani (A–V) hardening rule, the predicted ratcheting values at notch roots were found to be larger in magnitudes as compared with those of experimental data, while the predicted local ratcheting through the Chaboche (CH) hardening rule fell below the experimental data. Results consistently showed that as sample hardness increased, the local ratcheting at notch roots decreased.
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- 2024
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6. A narrative review on application of metal and metal oxide nanoparticles in endodontics
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Roohollah Sharifi, Ahmad Vatani, Amir Sabzi, and Mohsen Safaei
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Metal nanoparticles ,Metal oxide nanoparticles ,Dentistry ,Endodontics ,Human health ,Science (General) ,Q1-390 ,Social sciences (General) ,H1-99 - Abstract
The distinct physicochemical and biological characteristics of metal and metal oxide nanoparticles have attracted considerable interest in various branches of dentistry as potential solutions to the problems associated with conventional dental treatments and to promote human health. Many scientists have been interested in nanoparticles for endodontic applications in the last several decades. Endodontic treatment is more likely to be successful when metal and metal oxide nanoparticles are used. Endodontic therapies often make use of nanoparticles made of metals and metal oxides. The effect of nano metals and metal oxide in endodontic treatments has not been published or is not widely available in the literature. Therefore, this paper aims to review recent studies on the development and application of some important metal and metal oxide nanoparticles such as silver and silver oxide, zinc oxide, zirconium oxide, magnesium oxide, titanium dioxide and other metal oxide nanoparticles in endodontic therapeutic procedures.
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- 2024
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7. Burial of the Jackal
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Ahmad, V. Muzafar and Krishna Kumar, G.
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- 2011
8. The impact of theory-based education on promoting urinary tract infection prevention behaviours among elderly diabetic women – experimental study
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Elham Nejadsadeghi, Elham Eshaghi gorji, Ahmad Vakili-Basir, Samaneh Norouzi, Seyedeh Leila Dehghani, and Shahab Papi
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aging ,women ,diabetes ,urinary tract infection ,educational intervention. ,Medicine - Published
- 2024
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9. Antifungal activity of Fe3O4@SiO2/Schiff-base/Cu(II) magnetic nanoparticles against pathogenic Candida species
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Sedigheh Azadi, Esmat Azizipour, Ali Mohammad Amani, Ahmad Vaez, Zahra Zareshahrabadi, Alireza Abbaspour, Tahereh Firuzyar, Hengameh Dortaj, Hesam Kamyab, Shreeshivadasan Chelliapan, and Sareh Mosleh-Shirazi
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Cu(II) Nanoparticles ,Candida species ,Anti-fungal property ,Microdilution ,Cytotoxicity ,Medicine ,Science - Abstract
Abstract The antifungal efficacy and cytotoxicity of a novel nano-antifungal agent, the Fe3O4@SiO2/Schiff-base complex of Cu(II) magnetic nanoparticles (MNPs), have been assessed for targeting drug-resistant Candida species. Due to the rising issue of fungal infections, especially candidiasis, and resistance to traditional antifungals, there is an urgent need for new therapeutic strategies. Utilizing Schiff-base ligands known for their broad-spectrum antimicrobial activity, the Fe3O4@SiO2/Schiff-base/Cu(II) MNPs have been synthesized. The Fe3O4@SiO2/Schiff-base/Cu(II) MNPs was characterized by Fourier Transform-Infrared Spectroscopy (FT-IR), X-ray Diffraction (XRD), Transmission Electron Microscopy (TEM), Scanning Electron Microscopy (SEM), Dynamic Light Scattering (DLS), Energy-dispersive X-ray (EDX), Vibrating Sample Magnetometer (VSM), and Thermogravimetric analysis (TGA), demonstrating successful synthesis. The antifungal potential was evaluated against six Candida species (C. dubliniensis, C. krusei, C. tropicalis, C. parapsilosis, C. glabrata, and C. albicans) using the broth microdilution method. The results indicated strong antifungal activity in the range of 8–64 μg/mL with the lowest MIC (8 μg/mL) observed against C. parapsilosis. The result showed the MIC of 32 μg/mL against C. albicans as the most common infection source. The antifungal mechanism is likely due to the disruption of the fungal cell wall and membrane, along with increased reactive oxygen species (ROS) generation leading to cell death. The MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide) assay for cytotoxicity on mouse L929 fibroblastic cells suggested low toxicity and even enhanced cell proliferation at certain concentrations. This study demonstrates the promise of Fe3O4@SiO2/Schiff-base/Cu(II) MNPs as a potent antifungal agent with potential applications in the treatment of life-threatening fungal infections, healthcare-associated infections, and beyond.
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- 2024
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10. Frailty efficacy as a predictor of clinical and cognitive complications in patients undergoing coronary artery bypass grafting: a prospective cohort study
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Mehrnoosh Bakhtiari, Farhad Shaker, Fatemeh Ojaghi Shirmard, Arash Jalali, Ahmad Vakili-Basir, Mohammad Balabandian, Sima Shamshiri Khamene, Izat Mohammadkhawajah, Akbar Shafiee, Seyedeh Zahra Badrkhahan, and Kaveh Hosseini
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Frailty ,Coronary artery bypass grafting ,Cognitive function ,Independence level ,Depression status ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
Abstract Background Frailty is proposed as a predictor of outcomes in patients undergoing major surgeries, although data on the association of frailty and coronary artery bypass grafting (CABG) are lacking. We assessed the association between frailty and cognitive and clinical complications following CABG. Methods This prospective study included patients aged over 60 years undergoing elective CABG at Tehran Heart Center from 2020 to 2022. Baseline and three-month follow-up data on frailty using the Frail scale and clinical Frail scale, functional status using the Lawton Instrumental Activities of Daily Living Scale (IADL), cognitive function by Montreal Cognitive Assessment (MoCA), and depression by the Geriatric Depression Scale (GDS) were obtained. The incidence of adverse outcomes was investigated at the three-month follow-up. Outcomes between frail and non-frail groups were compared utilizing T-tests and Mann-Whitney U tests, as appropriate. Results We included 170 patients with a median age of 66 ± 4 years (75.3% male). Of these, 58 cases were classified as frail, and 112 individuals were non-frail, preoperatively. Frail patients demonstrated significantly worse baseline MOCA scores (21.08 vs. 22.41, P = 0.045), GDS (2.00 vs. 1.00, P = 0.009), and Lawton IADL (8.00 vs. 6.00, P
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- 2024
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11. Combining Plasma Extracellular Vesicle Let-7b-5p, miR-184 and Circulating miR-22-3p Levels for NSCLC Diagnosis and for Predicting Drug Resistance
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Vadla, G. P., primary, Daghat, B., additional, Garcia, A., additional, Perez, G., additional, Ahmad, V., additional, Patterson, N., additional, Manjunath, Y., additional, Kaifi, J.T., additional, Li, G., additional, and Chabu, C.Y., additional
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- 2021
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12. An overview of Indonesian doctors in combating COVID-19
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Ahmad V. Yudanto, Maria Ulfa, Dayu L. Wening, and Momoyo Azuma
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General Engineering - Abstract
Background: Indonesia's COVID-19 pandemic is putting a strain on the ability of health systems around the world to adapt and maintain sustainable performance. Indonesia has had more than four million cases of the disease and more than 141 thousand deaths in Indonesia. The hospital, along with other healthcare facilities, contributes to providing comprehensive individual health care in outpatient, inpatient, and emergency settings. Changes in facilities for patient accommodation, and acquisition of personal protective equipment (PPE) are all going through substantial changes. As doctors and health workers continue to work on this case every day while out in the field, many of their colleagues become ill and some die as a result. The aim of the study was intended to provide an overview of the conditions faced by doctors in Indonesia in dealing with COVID-19.Methods: The researchers surveyed the situation of 270 Indonesian doctors and specialists working during the COVID-19 pandemic. The questionnaires adapted from the WHO risk assessment tool for healthcare workers were translated into Bahasa Indonesia and distributed from April 2021 to May 2021 using a retrospective study.Results: Most respondents were female (61.5%) with an average age of 27.7. Forty respondents (14.8%) had a history of COVID-19.Conclusions: Based on compliance with using PPE and compliance with washing hands, doctors in Indonesia had a low risk of contracting COVID-19 from the healthcare facility environment. Even so, a correlation was found between the history of COVID-19 and happiness at work.
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- 2022
13. Predicting outcomes in patients with low ejection fraction undergoing coronary artery bypass graft
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Mohammad Sadeq Najafi, Soroush Nematollahi, Ahmad Vakili-Basir, Arash Jalali, Arezoo Gholami, Mohadese Dashtkoohi, Saeed Davoodi, Mina Pashang, Namvar Movahedi, Kyomars Abbasi, Soheil Mansourian, Haleh Ashraf, and Seyed Hossein Ahmadi Tafti
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Left ventricular dysfunction ,Coronary artery bypass grafting ,Cardiac adverse events ,Survival analysis ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
Introduction: Reduced left ventricular ejection fraction (LVEF) is a well-known predictor of adverse events after cardiac surgery. We aimed to assess the outcomes in patients with low LVEF undergoing coronary artery bypass graft. Methods: In this retrospective cohort, we included all patients with left ventricular ejection fraction ≤ 40 who underwent coronary artery bypass grafting between March 2007 and March 2016 (with a median follow-up of nine years) at Tehran Heart Center. Demographics and clinical characteristics were extracted from the data registry. Akaike information criterion (AIC) was used. The univariate Cox regression was performed. We investigated the predictors of mortality and major adverse cardiac and cerebrovascular events (MACCE) using Cox multivariable regression. Results: In total, 5,532 cases (79 % male) with a mean age of 65.58 were included in the study. The nine-year overall survival was calculated at 68 %, and more than half of the patients had MACCE (55 %). In adjusted multivariable Cox regression analysis, moderate to severe mitral valve regurgitation, glomerular filtration rate ≤ 60, mild right ventricular dysfunction, and valvular heart disease independently predicted higher mortality. The abovementioned predictors and peripheral vascular disease significantly increased MACCE. Conclusion: Our study indicates the clinical significance of mitral regurgitation, valvular heart disease, and renal function in patients with low ejection fraction treated by coronary artery bypass grafting surgery. Identifying predictors of adverse events can help with clinical decision-making and risk stratification, ultimately improving patient outcomes.
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- 2024
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14. First GC-MS Study of Essential Oil from Salvia bucharica
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Nadir, M., Rasheed, M., Ahmed, A., Ahmad, V. U., and Tareen, R. B.
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- 2014
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15. Nuclear Proteome Analysis of Monkey Embryonic Stem Cells During Differentiation
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Nasrabadi, Davood, Larijani, Mehran Rezaei, Fathi, Ali, Gourabi, Hamid, Dizaj, Ahmad V., Baharvand, Hossein, and Salekdeh, Ghasem Hosseini
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- 2010
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16. A genome-wide association meta-analysis implicates Hedgehog and Notch signaling in Dupuytren’s disease
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Sophie A. Riesmeijer, Zoha Kamali, Michael Ng, Dmitriy Drichel, Bram Piersma, Kerstin Becker, Thomas B. Layton, Jagdeep Nanchahal, Michael Nothnagel, Ahmad Vaez, Hans Christian Hennies, Paul M. N. Werker, Dominic Furniss, and Ilja M. Nolte
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Science - Abstract
Abstract Dupuytren’s disease (DD) is a highly heritable fibrotic disorder of the hand with incompletely understood etiology. A number of genetic loci, including Wnt signaling members, have been previously identified. Our overall aim was to identify novel genetic loci, to prioritize genes within the loci for functional studies, and to assess genetic correlation with associated disorders. We performed a meta-analysis of six DD genome-wide association studies from three European countries and extensive bioinformatic follow-up analyses. Leveraging 11,320 cases and 47,023 controls, we identified 85 genome-wide significant single nucleotide polymorphisms in 56 loci, of which 11 were novel, explaining 13.3–38.1% of disease variance. Gene prioritization implicated the Hedgehog and Notch signaling pathways. We also identified a significant genetic correlation with frozen shoulder. The pathways identified highlight the potential for new therapeutic targets and provide a basis for additional mechanistic studies for a common disorder that can severely impact hand function.
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- 2024
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17. Short and mid-term outcomes of valve-sparing, aortic root reimplantation (David’s procedure)
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Abbas Salehi Omran, Ali Aeen, Sepehr Nayebirad, Ahmad Vakili-Basir, Mohammad Sadeq Najafi, Reza Mohseni-Badalabadi, Shapour Shirani, Arezou Zoroufian, Arash Jalali, Fatemeh Alsadat Mostafanejad, and Mohammad Sahebjam
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Valve-sparing aortic root replacement ,David’s procedure ,Bentall procedure ,Aortic aneurysm ,Surgery ,RD1-811 ,Anesthesiology ,RD78.3-87.3 - Abstract
Abstract Background In the current study, we aimed to report the short- and mid-term outcomes of patients undergoing valve-sparing aortic root reimplantation (VSARR) and our center’s experience with the procedure. Methods Forty patients with aortic root aneurysms underwent VSARR at our center from 2010 until 2022. We retrospectively reviewed the medical records of these patients and extracted the relevant data. After carefully examining the aortic valve, the surgeon decided to perform Bentall or David’s procedure during the operation. Results The study population comprised 31 (77.5%) men and nine (22.5%) women, with a mean age of 55.35 ± 15.40. One patient developed hemodynamic instability post-surgery in the hospital and died from multi-organ failure. Another patient had severe AI in the intraoperative echocardiography, and aortic valve replacement with a prosthetic graft was performed during the same operation. In pre-operation echocardiography, 25 (62.5%) patients had severe, nine (22.5%) had moderate, and six (15%) had mild AI. In the in-hospital post-operation follow-up echo, AI was improved, and no patients had severe AI (P
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- 2024
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18. Research Performance in Reproductive Biomedicine: A National Scientometrics Study
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Zohreh Hashemian, Ahmad Vosough Dizaji, Mahdi Lotfipanah, Parvaneh Afsharian, and Massoud Vosough
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bibliometrics ,infertility ,iran ,reproductive ,scientometric ,Medicine (General) ,R5-920 - Abstract
Recent achievements in reproductive biomedicine have led to a revolution in infertility treatment. A comprehensive understandingof the current status of reproductive medicine is necessary for the development of a forward-looking plan byhealth policymakers, based on fundamental requirements. This study is a systematic review of the Scopus database toassess reproductive biomedicine publications within Iran and compared to the rest of the world from 1990 to 2020. Thedata were categorized by geographical distribution across five continents. National data were assessed in comparisonwith the world and with neighboring countries. Finally, prominent national research institutes in the field of reproductivebiomedicine in Iran were identified, and their contributions to the field highlighted. Of the five continents, the highestnumber of publications and citations is from Europe (36% publications and 41.5% citations). Corresponding numbers forthe other continents are 32 and 33% for America, and 26 and 18.4% for Asia respectively. The remaining publications andcitations were from Australia (3.8 and 4.1%) and Africa (2.6 and 3.1%). In a national analysis, the highest-ranking institutesin reproductive biomedicine are in Tehran province (50.9% of all Iranian publications), Shiraz (8.8%), Yazd (7.8%),Isfahan (7.1%), and Tabriz (6.9%). More specifically, Tehran University of Medical Science (15.9%), the Royan Institute(12.2%), Shahid Beheshti Medical University (10.1%), Shahid Sadoughi University of Medical Sciences (6.9%), andTarbiat Modares University (6.7%) account for more than 50% of all Iranian scientific publications. In recent decades,reproductive biomedical research has grown significantly in Iran. Reviewing publications in this field helps health policydecision makers to monitor the direction of research and adjust investment in the treatment of infertility. In addition, it isnecessary to expand and organize inter-organizational and international collaborations to improve the research, gain thebenefits of different experiences, and engage in international multicenter studies.
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- 2024
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19. The Need for Smart Materials in an Expanding Smart World: MXene-Based Wearable Electronics and Their Advantageous Applications
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Ali Mohammad Amani, Lobat Tayebi, Milad Abbasi, Ahmad Vaez, Hesam Kamyab, Shreeshivadasan Chelliapan, and Ehsan Vafa
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Chemistry ,QD1-999 - Published
- 2023
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20. Segmental and global longitudinal strain measurement by 2-dimensional speckle tracking echocardiography in severe rheumatic mitral stenosis
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Samira Mehrabi-Pari, Sepehr Nayebirad, Akbar Shafiee, Ahmad Vakili-Basir, Reza Hali, Mojgan Ghavami, and Arash Jalali
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Rheumatic Heart Disease ,Mitral stenosis ,Left ventricular dysfunction ,Strain measurement ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
Abstract Background The present study aimed to detect subtle left ventricular (LV) dysfunction in patients with severe rheumatic mitral stenosis (MS) by measuring global and segmental longitudinal strain with a two-dimensional speckle tracking echocardiography (2D-STE) method. Methods In this case-control study, 65 patients with severe rheumatic MS and preserved ejection fraction (EF ≥ 50% measured by conventional echocardiographic methods) were compared with 31 otherwise healthy control subjects. All patients underwent LV strain measurement by the 2D-STE method in addition to conventional echocardiography using a VIVID S60 echocardiography device. Results Absolute strain values in myocardial segments 1–8, 10, and 12 (all basal, mid anterior, mid anteroseptal, mid inferior, and mid anterolateral segments) were significantly lower in patients with severe MS compared with the control group (P
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- 2023
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21. Charge and exciton dynamics of OLEDs under high voltage nanosecond pulse: towards injection lasing
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Ahmad, V., Sobus, J., Greenberg, M., Shukla, A., Philippa, B., Pivrikas, A., Vamvounis, G., White, R., Lo, S-C, Namdas, E.B., Ahmad, V., Sobus, J., Greenberg, M., Shukla, A., Philippa, B., Pivrikas, A., Vamvounis, G., White, R., Lo, S-C, and Namdas, E.B.
- Abstract
Electrical pumping of organic semiconductor devices involves charge injection, transport, device on/off dynamics, exciton formation and annihilation processes. A comprehensive model analysing those entwined processes together is most helpful in determining the dominating loss pathways. In this paper, we report experimental and theoretical results of Super Yellow (Poly(p-phenylene vinylene) co-polymer) organic light emitting diodes operating at high current density under high voltage nanosecond pulses. We demonstrate complete exciton and charge carrier dynamics of devices, starting from charge injection to light emission, in a time scale spanning from the sub-ns to microsecond region, and compare results with optical pumping. The experimental data is accurately replicated by simulation, which provides a robust test platform for any organic materials. The universality of our model is successfully demonstrated by its application to three other laser active materials. The findings provide a tool to narrow the search for material and device designs for injection lasing.
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- 2020
22. Antidiabetic Flavonol Glycosides from Eryngium caeruleum
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Rehman, A. U., Hashmi, M. A., Tehseen, Y., Khan, A., Khan, S. S., Iqbal, J., Perveen, S., Khan, S., Umar Farooq, and Ahmad, V. U.
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glucosidase ,lcsh:Chemistry ,lcsh:QD241-441 ,molecular docking ,lcsh:QD1-999 ,lcsh:Organic chemistry ,lcsh:Botany ,flavone glycosides ,eryngium caeruleum ,aldose reductase ,antiglycation ,lcsh:QK1-989 - Abstract
Phytochemical investigation of the aerial parts of Eryngium caeruleum led to the isolation of two new source flavone glycosides (1 and 2). The structures of these compounds were determined with the help of one- and two-dimensional (1D- and 2D-) NMR techniques including 1H-NMR, 13C-NMR, HMQC, HMBC, 1H- 1H COSY, and NOESY experiments. The compounds were studied for their in vitro aldose reductase (ALR1 and ALR2) and glucosidase (α and β) inhibitory activities, and antiglycation potential. Both the compounds showed higher inhibition potential against ALR1 than ALR2. Compound 2 showed three fold higher potency against ALR2 than the reference drug Sorbinil. In silico studies were performed to understand the binding mechanism of these compounds to aldose reductase .
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- 2018
23. Pharmacological activities of crude acetone extract and purified constituents of Salvia moorcraftiana Wall
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Khan, T., Zahid, M., Asim, M., Iqbal, Z., Choudhary, M. Iqbal, and Ahmad, V. Uddin
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Medicine, Botanic -- Evaluation -- Physiological aspects ,Antifungal agents -- Evaluation ,Salvia -- Physiological aspects ,Medicine, Herbal -- Evaluation -- Physiological aspects ,Biological sciences ,Health ,Science and technology ,Evaluation ,Physiological aspects - Abstract
Summary The crude acetone extract of aerial parts of Salvia moorcraftiana Wall. was screened for various biological activities including Lemna bioassay, antifungal, antibacterial, leishmanicidal, insecticidal activities and brine shrimp cytotoxicity. [...]
- Published
- 2002
24. Diversivittatin, a new phenylpropanoid derivative from the roots of Ferula diversivittata
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Iranshahi, M., Hosseini, S. T., Sahebkar, A. H., Khan, S. Suleman, and Ahmad, V. U.
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- 2010
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25. A new method for the green synthesis of Fe3O4 nanoparticles using Alliaceae plant extract and investigating their properties
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ali mohammad amani, Kazem jamali, Ali Jangjou, Ehsan Vafa, Milad Abbasi, Sareh Mosleh Shirazi, Seyed Reza Kasaei, and Ahmad Vaez
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magnetite nanoparticles ,allium hooshidaryae ,green synthesis ,Materials of engineering and construction. Mechanics of materials ,TA401-492 - Abstract
Abstract Introduction: In recent years, iron oxide-based magnetic nanoparticles have been widely used for a variety of environmental and medical applications, including the purification and separation of pharmaceutical, dye, and heavy metal contaminants, as well as drug delivery and labeling systems. Due to the fact that magnetite (Fe3O4) has superior magnetic and electrical properties, iron oxide has attracted the most interest among many nanostructured materials. Methods: In this research, magnetite nanoparticles (Fe3O4) were successfully synthesized using a green process. This method is simple, fast, cost-effective, and biocompatible. Allium hooshidaryae (Alliaceae) plant extract was used as a stabilizing and reducing agent in this process. Green synthesized nanoparticles were characterized by several structural and physical techniques, like Vibrating Sample Magnetometer (VSM), X-ray Diffraction (XRD), Fourier Transform Infrared (FTIR), Energy Dispersive X-ray Spectroscopy (EDS), Transmission Electron Microscope (TEM) ) and scanning electron microscope (SEM). Findings: XRD results showed that the synthesized nanoparticles are FCC structure with high purity. FTIR results proved the binding of functional group present in this plant and Fe3O4 nanoparticles. Also, in FTIR analysis, the presence of two absorption peaks of 559.96 cm-1 and 432.57 cm-1 confirmed the successful green synthesis of Fe3O4 nanoparticles. SEM and TEM images showed that the green synthesized Fe3O4 nanoparticles are mostly spherical and have an average size of 35.73 nm. As a result, the synthesized nanoparticles have the potential to have useful benefits in future nanomedicine
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- 2023
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26. Exploring new subgroups for irritable bowel syndrome using a machine learning algorithm
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Elahe Mousavi, Ammar Hassanzadeh Keshteli, Mohammadreza Sehhati, Ahmad Vaez, and Peyman Adibi
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Medicine ,Science - Abstract
Abstract Irritable bowel syndrome (IBS) is a complicated gut-brain axis disorder that has typically been classified into subgroups based on the major abnormal stool consistency and frequency. The presence of components other than lower gastrointestinal (GI) symptoms, such as psychological burden, has also been observed in IBS manifestations. The purpose of this research is to redefine IBS subgroups based on upper GI symptoms and psychological factors in addition to lower GI symptoms using an unsupervised machine learning algorithm. The clustering of 988 individuals who met the Rome III criteria for diagnosis of IBS was performed using a mixed-type data clustering algorithm. Nine sub-groups emerged from the proposed clustering: (I) High diarrhea, pain, and psychological burden, (II) High upper GI, moderate lower GI, and psychological burden, (III) High psychological burden and moderate overall GI, (IV) High constipation, moderate upper GI, and high psychological burden, (V) moderate constipation and low psychological burden, (VI) High diarrhea and moderate psychological burden, (VII) moderate diarrhea and low psychological burden, (VIII) Low overall GI, and psychological burden, (IX) Moderate lower GI, and low psychological burden. The proposed procedure led to the discovery of new homogeneous clusters in addition to certain well-known Rome sub-types for IBS.
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- 2023
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27. Evaluation of Predicting Factors Affecting Sperm Retrieval in Patients with Klinefelter Syndrome: A Prospective Study
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Fereshteh Aliakbari, Neda Taghizabet, Fatemeh Rezaei-Tazangi, Hamid Kalantari, Ahmad Vosough Dizaj, Maryam Mohammadi, Hesamoddin Sajadi, and Mohammad Ali Sadighi Gilani
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azoospermic ,klinefelter ,testicular sperm extraction ,ultrasonography ,Medicine (General) ,R5-920 - Abstract
Background: This study aimed to evaluate the predicting factors affecting sperm retrieval. We prospectively assessedthe relationship between sonographic and microdissection testicular sperm extraction (mTESE) findings in Klinefeltersyndrome (KS).Materials and Methods: In this prospective study, 44 azoospermic men with 47, XXY karyotypes participated in thisstudy. In order to evaluate the amount of blood supply in different parts of testicular tissue, a doppler ultra-sonographicwas performed. Also, for the detection of sperm in this group mTESE technique was performed.Results: The age average of positive mTESE and negative mTESE groups was 29.4 and 33.6 years, respectively. Bycomparing the testicle volume (based on the data obtained from the clinical examinations conducted by the urologist)it was determined that there is no significant difference between mTESE positive and negative groups. Folliclestimulatinghormone (FSH) levels in men with negative mTESE (P=0.03) and testosterone levels in men with positivemTESE significantly increased (P=0.017). The overall rate of testis vascularity was significantly higher in the positivemTESE group than in the negative mTESE group. The clinical pregnancy rate in positive mTESE men was 9% percycle, 16.6% per embryos were transferred (ET), and 12.5% per cycle.Conclusion: Totally, our observation indicated that there is not a significant relationship between sonographic and mTESEresults in KS patients. However, more investigations with bigger sample Size can be useful to validate our results.
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- 2023
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28. Mineralogy, Geochemistry, and Origin of Nickel-Bearing Laterites in the Northwestern of Noorabad (Lorestan Province)
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Peyman Eskandarnia, Ahmad Ahmadi Khalaji, Masoud Kiani, Ahmad Valipour, and Zahra Tahmasbi
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smectite ,bauxite ,laterite ,ophiolite ,noorabad ,Geology ,QE1-996.5 - Abstract
The nickel-bearing laterites of Noorabad area are seen in the high Zagros zone along with Kermanshah ophiolitic complex. The ophiolitic complex in the studied area includes serpentinized peridotites, isotropic gabbros, plagiogranite, sheeted dykes, basaltic lavas, andesite, and radiolarite. The peridotites of this ophiolitic complex include dunite, harzburgite, and lherzolite. The tectonic activities have caused tectonization in these rocks in such a way that it has facilitated their alteration process and created laterite zones. The alterations of peridotite rocks include serpentine, dolomite, hematite, and silicification. The laterite zone is layered and lens-shaped red horizon on peridotite rocks and is covered by Miocene limestones. Based on XRD analysis, mineralogy of the lateritic zone includes dolomite, quartz, smectite, and serpentine. The ratio of La/Y changes indicates that the studied laterites were formed in alkaline pH. According to the discrimination diagrams of the source rock, the studied laterites are karst bauxites with ultrabasic origin. Introduction Laterites are formed in areas with long tectonic stability and low erosion rates (Brand et al., 1998). Usually, the source rock of these laterites is serpentinites. Nickel is washed from the profile upper parts and concentrates in the lower parts, causing the enrichment and formation of nickel-bearing laterites. Most nickel-bearing laterite profiles have two ore types, an oxide component and a hydrous silicate or clay silicate component (Brand et al., 1998). The richest deposits of nickel-bearing laterite are formed where oxide-rich regoliths rise and nickel is washed down to the new silicates in saprolite (absolute accumulation) to be concentrated (Butt & Cluzel, 2013). This study tried to investigate the field geology, mineralogy, lateritization process, and geochemistry of Noorabad laterites (northwest of Lorestan province, Iran). Materials and methods The field operations were carried out in several rounds and led to the collection of 30 samples from serpentines and laterites of the studied area. Then, by preparing 25 thin and polished sections, the geological characteristics of ores, especially their texture and associated minerals, were discussed. Then three soil laterite samples, for mineralogical study by XRD method were sent to the central lab of Lorestan University and 10 rock and soil samples from the laterites of the studied area were sent to the Canadian SGS laboratory for determining the amount of major and minor elements by ICP-MS method. Results The peridotite rocks of Noorabad ophiolite complex in the northwest of Lorestan province include dunite, harzburgite, and lherzolite, which have been strongly affected by alteration. The tectonic activities have caused crushing in these rocks in a way that has facilitated their alteration process and created laterite areas. As a result of different alteration processes such as serpentinization, carbonation, hematitization, and silicification, primary minerals such as olivine, pyroxene, and spinel have been altered and secondary minerals such as serpentine, dolomite, quartz, hematite, and smectite have been formed. The laterite zone is a layered red horizon and in some areas is lenticular, which is located on peridotite rocks. In some areas it is covered by Miocene limestones. In some areas, the secondary fractures of laterites formed by tectonic and diagenesis activities are filled by dolomite and silica. According to XRD analysis, there are dolomite, quartz, hematite, smectite and serpentine group minerals in the laterite section. The chemical analysis of the studied samples shows the nickel content of 381-2660 ppm for Noorabad laterites. According to the discrimination diagrams of source rock, the studied laterites are derived from ultramafic rocks. Moreover, the investigations carried out on the La/Y ratio showed that the formation environment for the studied laterite samples is alkaline. Discussion The peridotite rocks of Kermanshah ophiolite are related to suprasubduction ophiolites (Kiani, 2011). Due to the multi-stage replacement mechanism, these types of peridotites undergo the most serpentine alteration, so that their severe crushing during replacement and their migration on the margins of the continents facilitate the intensity of the altered. The peridotites of northwestern of Lorestan province were altered into serpentine during these alterations in the initial stages, and then underwent carbonate, hematite, and silicification alterations. During these changes, the primary minerals of these peridotites, such as olivine, pyroxene, and spinel, have become secondary minerals. The serpentine minerals are the first group of secondary minerals that were formed. Then, the secondary minerals of the second stage replaced the serpentines in such a way that the minerals of the smectite group can directly replace the serpentine (Dixon, 1989; Nahon et al., 1989; Gaudin et al., 2005). Other minerals are formed by substitution and saturation of other elements and form minerals with simple chemical formula such as quartz, dolomite, and hematite. During the first stages of alteration of peridotite rocks, the main elements Si, Mg, Ca, Fe, and Al were washed from the rock and caused the formation of secondary minerals in the lateritic zone. A significant amount of silica is included in the structure of silicate minerals such as serpentine and smectite, and the rest is filled in fractures in the form of chert and chalcedony. During the weathering process, magnesium-bearing minerals are destroyed and Mg2+ is removed from them, so that some of the magnesium in the serpentine mineral are replaced by Ni2+ (Sagapoa et al., 2011) and nickel-bearing serpentine minerals. The Ca element is removed from the pyroxene group minerals during alteration and enters the structure of smectite minerals or forms dolomite mineral. The Ni element has a positive correlation with the Co, Mg, Cr, and Fe elements, and this correlation can be due to the substitution of nickel instead of these elements in the crystal network of secondary minerals or due to the surface absorption of the mentioned elements by the hematite mineral.
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- 2023
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29. Designing a model of psychological behavior of compulsive buyers in relation to brands: Based on qualitative approach and grounded theory method
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Sadaf AliArab, Bahram Kheiri, Hasan Esmailpour, and Ahmad Vedadi
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psychological factors ,qualitative research ,contextual conditions ,intervening conditions ,Psychiatry ,RC435-571 ,Psychology ,BF1-990 - Abstract
Introduction: In the last two decades, the literature in field of consumer behavior has paid a lot of attention to the issue of compulsive buying, but there are gaps. Aim: The purpose of research was to design a model of the psychological behavior of compulsive buyers in relation to brands based on the qualitative approach. Method: In the research, a qualitative approach based on the foundational data theory was used. The studied population included residents of Tehran in 2021 with an age range of 16 to 50 years who had compulsive buying disorder, and specialists in psychology and psychiatry, and marketing managers from Tehran with at least 10 years of experience. In order to collect data, the semi-structured interview method and the Compulsive Buying Behavior Diagnosis Questionnaire of Maccarrone & Schofield (2017) were used. Open, central, and selective coding, with Max QDA software version 20, and SPSS version 26 were used for data analysis. Results: The found model showed that contextual conditions (psychological and sociological factors), along with intervening conditions (concepts related to the brand, lifestyle display, income, intensifying negative feelings), in formation of compulsive buyers in relation to brands is effective and social and emotional benefits from buying the brand were the cause of this behavior. In the meantime, the behaviors of compulsive buyers in relation to brands (floating among brands and listening to brands) leads to adverse consequences from a marketing point of view. Conclusion: Based on results, the formation of hating feeling towards the brand causes irreparable damage to the brand, and due to the presence of social networks, these feelings can be quickly transmitted among consumers and lead to the brand's reputation damage.
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- 2023
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30. Clinical manifestation for immunoglobulin A deficiency: a systematic review and meta-analysis
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Ahmad Vosughimotlagh, Seyed Erfan Rasouli, Hosein Rafiemanesh, Molood Safarirad, Niusha Sharifinejad, Atossa Madanipour, Maria Marluce Dos Santos Vilela, Edyta Heropolitańska-Pliszka, and Gholamreza Azizi
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Immunoglobulin A deficiency ,Autoimmune disorders ,Infections ,Malignancy ,Allergic diseases ,Immunologic diseases. Allergy ,RC581-607 - Abstract
Abstract Objectives Immunoglobulin A deficiency (IgAD) is a common disease with an unknown genetic defect, characterized by the decreased or absent IgA with other isotypes normal, normal subclasses, and specific antibodies. Patients with this disorder represent a spectrum of clinical manifestations including infections, autoimmune disorders, malignancy, and allergic diseases. The current study aimed to evaluate their prevalence and categorized them. Methods We searched PubMed, Web of Science, and Scopus databases to find eligible studies from the earliest available date to January 2022 with standard keywords. Pooled estimates of clinical manifestations prevalence and the corresponding 95% confidence intervals were calculated using random-effects models. Results The most prevalent clinical manifestations belonged to infection (64.8%) followed by allergic diseases (26.16%) and autoimmunity (22.0%), respectively. In selective IgA deficiency patients as the largest group of IgAD in current study, celiac disease (6.57%), Inflammatory bowel disease (4.01%), and rheumatoid arthritis (3.80%) were the most prevalent autoimmunity. Meanwhile, the most frequent infection was respiratory tract infection, fungal infection, and gastrointestinal infection at 50.74%, 18.48%, and 15.79%, respectively. In addition, the pooled prevalence of asthma, allergic rhinitis, and allergic conjunctivitis were 19.06%, 15.46%, and 11.68%, respectively which were reported as the most widespread allergic diseases. Conclusions Our results showed that apart from undiagnosed IgAD patients, IgAD patients represent a wide range of clinical manifestations. Infection, allergy, and autoimmunity are the most common clinical manifestations. The concurrent presence of IgA and IgG subtypes deficiency could be associated with increased susceptibility to infection. Considering the probability of developing new clinical complications during follow-up, periodic assessments of IgAD patients should be inspected.
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- 2023
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31. Re-investigation of functional gastrointestinal disorders utilizing a machine learning approach
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Elahe Mousavi, Ammar Hasanzadeh Keshteli, Mohammadreza Sehhati, Ahmad Vaez, and Peyman Adibi
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Functional gastrointestinal disorders ,Unsupervised machine learning ,Cluster analysis ,Rome criteria ,FGID ,Computer applications to medicine. Medical informatics ,R858-859.7 - Abstract
Abstract Background Functional gastrointestinal disorders (FGIDs), as a group of syndromes with no identified structural or pathophysiological biomarkers, are currently classified by Rome criteria based on gastrointestinal symptoms (GI). However, the high overlap among FGIDs in patients makes treatment and identifying underlying mechanisms challenging. Furthermore, disregarding psychological factors in the current classification, despite their approved relationship with GI symptoms, underlines the necessity of more investigation into grouping FGID patients. We aimed to provide more homogenous and well-separated clusters based on both GI and psychological characteristics for patients with FGIDs using an unsupervised machine learning algorithm. Methods Based on a cross-sectional study, 3765 (79%) patients with at least one FGID were included in the current study. In the first step, the clustering utilizing a machine learning algorithm was merely executed based on GI symptoms. In the second step, considering the previous step's results and focusing on the clusters with a diverse combination of GI symptoms, the clustering was re-conducted based on both GI symptoms and psychological factors. Results The first phase clustering of all participants based on GI symptoms resulted in the formation of pure and non-pure clusters. Pure clusters exactly illustrated the properties of most pure Rome syndromes. Re-clustering the members of the non-pure clusters based on GI and psychological factors (i.e., the second clustering step) resulted in eight new clusters, indicating the dominance of multiple factors but well-discriminated from other clusters. The results of the second step especially highlight the impact of psychological factors in grouping FGIDs. Conclusions In the current study, the existence of Rome disorders, which were previously defined by expert opinion-based consensus, was approved, and, eight new clusters with multiple dominant symptoms based on GI and psychological factors were also introduced. The more homogeneous clusters of patients could lead to the design of more precise clinical experiments and further targeted patient care.
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- 2023
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32. Pathway-Based Mendelian Randomization for Pre-Infection IL-6 Levels Highlights Its Role in Coronavirus Disease
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Zoha Kamali, Nafiseh Esmaeil, Chris H. L. Thio, Ahmad Vaez, and Harold Snieder
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severe COVID-19 ,interleukin 6 ,GWAS ,mendelian randomization ,causality ,Genetics ,QH426-470 - Abstract
Objectives: Interleukin 6 (IL-6) levels at hospital admission have been suggested for disease prognosis, and IL-6 antagonists have been suggested for the treatment of patients with severe COVID-19. However, less is known about the relationship between pre-COVID-19 IL-6 levels and the risk of severe COVID-19. To fill in this gap, here we extensively investigated the association of genetically instrumented IL-6 pathway components with the risk of severe COVID-19. Methods: We used a two-sample Mendelian randomization study design and retrieved genetic instruments for blood biomarkers of IL-6 activation, including IL-6, soluble IL-6 receptor, IL-6 signal transducer, and CRP, from respective large available GWASs. To establish associations of these instruments with COVID-19 outcomes, we used data from the Host Genetics Initiative and GenOMICC studies. Results: Our analyses revealed inverse associations of genetically instrumented levels of IL-6 and its soluble receptor with the risk of developing severe disease (OR = 0.60 and 0.94, respectively). They also demonstrated a positive association of severe disease with the soluble signal transducer level (OR = 1.13). Only IL-6 associations with severe COVID-19 outcomes reached the significance threshold corrected for multiple testing (p < 0.003; with COVID-19 hospitalization and critical illness). Conclusions: These potential causal relationships for pre-COVID-19 IL-6 levels with the risk of developing severe symptoms provide opportunities for further evaluation of these factors as prognostic/preventive markers of severe COVID-19. Further studies will need to clarify whether the higher risk for a severe disease course with lower baseline IL-6 levels may also extend to other infectious diseases.
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- 2024
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33. Designing a Policymaking Pattern to Deal with Covid-19
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Hasan Yusefzadeh, Hassan Nazari, Ahmad Vadadi, and Reza Mohammadpour
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covid-19 ,design ,pattern ,policy making ,qualitative research ,Public aspects of medicine ,RA1-1270 - Abstract
Background: Due to the unpredictability of Covid-19, policymakers should look at this issue as a complex system in developing and providing solutions to deal with it. This research aimed to provide a policy model for dealing with Covid-19.Methods: This is a qualitative study and used the theme analysis method. Data collection tools were semi-structured interviews and data analysis in open, centralized, and selective coding stages. The research area was the universities of medical sciences affiliated with the Ministry of Health. The research population of this study included senior managers and their successors who worked in the Corona headquarters with sufficient familiarity with coronavirus issues and practical and managerial experience and supervision of universities and hospitals. In this research, the required data were collected using field methods and interviews with 15 people theoretically and purposefully until the theoretical saturation was reached. The validity of the interview questions was reviewed and confirmed by experts.Results: After analyzing the interviews and integrating the duplicate codes in several stages, 168 codes were obtained and divided into three main categories. These categories included information on the covid-19 in nine subcategories, sections dealing with covid-19 in seven subcategories, and a policy formulation framework in four subcategories.Conclusion: Given the interdependence of economic, social, and cultural systems in the development of policies related to covid-19 and systemic threats, all aspects should be considered.
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- 2023
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34. Bacterial Profile and Antibiotic Use in Catheter-Associated Urinary Tract Infection Patients at a Tertiary Referral Hospital in Surabaya, Indonesia
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Ahmad Veri Erianto, Tri Pudy Asmarawati, Agung Dwi Wahyu Widodo, and Brian Eka Rachman
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infectinous disease ,escherichia coli ,descriptive study. ,Medicine - Abstract
Highlights: • This study examined patients with catheter-associated urinary tract infections (CAUTI) to find the prevalent bacteria and the frequency of antibiotic use. • Extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli sensitive to amikacin was found to be the most common pathogen in CAUTI, while ceftriaxone was the most commonly used antibiotic. Abstract Catheter-associated urinary tract infection (CAUTI) is the most typical type of infection associated with healthcare. This infection constitutes a significant health problem due to its complications and frequent recurrence. The high annual incidence of CAUTI leads to infectious complications and a high cost of treatment. Antibiotic-resistant bacteria further complicate the problem because multiresistant pathogenic bacteria are often responsible for these infections. Moreover, the lack of a comprehensive case reporting system in Indonesia hinders the determination of CAUTI incidence. This study aimed to determine the bacterial profile and antibiotic use in CAUTI patients (n=22) at the Internal Medicine Inpatient Unit of Dr. Soetomo General Academic Hospital, Surabaya, Indonesia. This retrospective descriptive study collected data from patient medical records to describe the incidence, type of bacteria, sensitivity patterns, and antibiotic use in CAUTI patients. The data collection process included collecting medical records, recording information on data collection sheets, and recapitulating and analyzing the data. The criteria for CAUTI diagnosis were a bacterial count of ≥105 CFU/mL and a catheterization that lasted more than 48 hours. Samples were selected using non-probability sampling, also known as saturation sampling. Meanwhile, variables analyzed in this study were the type of pathogenic bacteria, antibiotics used, age, and sex. Descriptive analysis was employed to analyze the data. The findings suggested that the most common bacteria were Escherichia coli, with eight of nine bacteria showing extended-spectrum beta-lactamase (ESBL) production. Female patients aged 35–65 years were the majority of the CAUTI patients. Amikacin was the antibiotic with the highest sensitivity (90.9%), while ceftriaxone was the most common type of antibiotic administered to the patients. In addition, intravenous (IV) administration was the most common route of antibiotic administration, with an average therapy duration of seven days. In conclusion, identifying the type of pathogenic bacteria and performing antibiotic susceptibility testing can help minimize antibiotic resistance and prevent more severe complications in CAUTI patients.
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- 2023
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35. Breast cancer brain metastasis: from etiology to state-of-the-art modeling
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Mohammad Kamalabadi Farahani, Maliheh Gharibshahian, Alireza Rezvani, and Ahmad Vaez
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Brain metastasis ,Breast cancer ,Tissue engineering ,Scaffold ,Cancer modeling ,Cancer cell lines ,Biology (General) ,QH301-705.5 - Abstract
Abstract Currently, breast carcinoma is the most common form of malignancy and the main cause of cancer mortality in women worldwide. The metastasis of cancer cells from the primary tumor site to other organs in the body, notably the lungs, bones, brain, and liver, is what causes breast cancer to ultimately be fatal. Brain metastases occur in as many as 30% of patients with advanced breast cancer, and the 1-year survival rate of these patients is around 20%. Many researchers have focused on brain metastasis, but due to its complexities, many aspects of this process are still relatively unclear. To develop and test novel therapies for this fatal condition, pre-clinical models are required that can mimic the biological processes involved in breast cancer brain metastasis (BCBM). The application of many breakthroughs in the area of tissue engineering has resulted in the development of scaffold or matrix-based culture methods that more accurately imitate the original extracellular matrix (ECM) of metastatic tumors. Furthermore, specific cell lines are now being used to create three-dimensional (3D) cultures that can be used to model metastasis. These 3D cultures satisfy the requirement for in vitro methodologies that allow for a more accurate investigation of the molecular pathways as well as a more in-depth examination of the effects of the medication being tested. In this review, we talk about the latest advances in modeling BCBM using cell lines, animals, and tissue engineering methods.
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- 2023
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36. An intriguing approach toward antibacterial activity of green synthesized Rutin-templated mesoporous silica nanoparticles decorated with nanosilver
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Milad Abbasi, Razieh Gholizadeh, Seyed Reza Kasaee, Ahmad Vaez, Shreeshivadasan Chelliapan, Fouad Fadhil Al-Qaim, Issa Farhan Deyab, Mostafa Shafiee, Zahra Zareshahrabadi, Ali Mohammad Amani, Sareh Mosleh-Shirazi, and Hesam Kamyab
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Medicine ,Science - Abstract
Abstract In recent years, mesoporous silica nanoparticles (MSNs) have been applied in various biomedicine fields like bioimaging, drug delivery, and antibacterial alternatives. MSNs could be manufactured through green synthetic methods as environmentally friendly and sustainable synthesis approaches, to improve physiochemical characteristics for biomedical applications. In the present research, we used Rutin (Ru) extract, a biocompatible flavonoid, as the reducing agent and nonsurfactant template for the green synthesis of Ag-decorated MSNs. Transmission electron microscopy (TEM), zeta-potential, x-ray powder diffraction (XRD), fourier transform infrared (FTIR) spectroscopy analysis, scanning electron microscopy (SEM), brunauer–emmett–teller (BET) analysis, and energy-dispersive system (EDS) spectroscopy were used to evaluate the Ag-decorated MSNs physical characteristics. The antimicrobial properties were evaluated against Staphylococcus aureus (S. aureus), Escherichia coli (E. coli), and also different types of candida. The cytotoxicity test was performed by using the MTT assay. Based on the findings, the significant antimicrobial efficacy of Ru-Ag-decorated MSNs against both gram positive and gram negative bacteria and different types of fungi was detected as well as acceptable safety and low cytotoxicity even at lower concentrations. Our results have given a straightforward and cost-effective method for fabricating biodegradable Ag-decorated MSNs. The applications of these MSNs in the domains of biomedicine appear to be promising.
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- 2023
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37. A model of managerial competencies affecting the performance of social security hospitals in Tehran, Iran
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Mehdi Rezaei Yazdeli, Ahmad Vedadi, Mohammad Reza Rabiee Mandajin, and Mina Jamshidi Avanaki
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competency model ,hospital managers ,social security ,Medicine ,Medicine (General) ,R5-920 - Abstract
Objective(s): The purpose of this study was to explain and present a model of managerial competencies affecting the performance of social security hospitals in Tehran, Iran. Methods: This was a qualitative study. A purposive sampling was applied. The participants were senior managers of social security medical centers and experts in hospital management and administration. Data was collected through in-depth semi-structured interviews and continued until saturation. A thematic approach was used to analyze the data. Results: The results led to the identification of 4 comprehensive themes, 10 organizing themes and 40 basic themes. Comprehensive and organizing themes included knowledge and work experience (specialized knowledge, general knowledge, work experience), individual characteristics (moral characteristics, personality traits), interactive competencies (communication skills, internal-organizational communication, external-organizational communication), and executive competencies (managerial competencies, leadership competencies) Conclusion: The use of identified themes can be useful in employing competent managers or be used as the basis of routine in-service training courses for hospital managers in medical centers.
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- 2023
38. Mediating Roles of Stress, Anxiety, and Depression in the Relationship between Constipation and Sleep Quality among the Elderly: Structural Equation Modeling (SEM)
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Shahab Papi, Azin Barmala, Zeynab Amiri, Ahmad Vakili-Basir, Maria Cheraghi, and Elham Nejadsadeghi
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sleep ,constipation ,anxiety ,depression ,Psychology ,BF1-990 ,Consciousness. Cognition ,BF309-499 - Abstract
Introduction Sleep quality is an important health index in the elderly. As age increases, changes occur in sleep quality leading to sleep disorders and recurrent complaints. Sleep quality management of the elderly requires identification of its determinants. The present study aimed to determine the mediating roles of stress, anxiety, and depression in the relationship between constipation and sleep quality among the elderly using structural equation modeling (SEM). Materials and Methods A correlational design was used in the present study through structural equation modeling. In this work, 363 elderlies were examined by multi-stage random sampling. Data collection tools included four questionnaires, namely a demographic information questionnaire, the constipation questionnaire (ROME III), the Depression, Anxiety, and Stress Scale-short form, and the Pittsburgh Sleep Quality Index (PSQI), which were completed by interview and the self-report method. The SPSS Statistics for Windows, version 22.0, and SPSS AMOS (IBM Corp., Armonk, NY, USA) were used to analyze the data. Results The results indicated that the proposed model had an acceptable fit (p
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- 2023
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39. cis-Isogeraniol, a recruitment pheromone of the antLeptogenys diminuta: Pheromones, 77 [1]
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Attygalle, A. B., Steghaus-Kovac, S., Ahmad, V. U., Maschwitz, U., Vostrowsky, O., and Bestmann, H. J.
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- 1991
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40. Transcriptomics- and Genomics-Guided Drug Repurposing for the Treatment of Vesicular Hand Eczema
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Fieke M. Rosenberg, Zoha Kamali, Angelique N. Voorberg, Thijs H. Oude Munnink, Peter J. van der Most, Harold Snieder, Ahmad Vaez, and Marie L. A. Schuttelaar
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vesicular hand eczema ,hand eczema ,transcriptomics ,genomics ,drug repurposing ,treatment ,Pharmacy and materia medica ,RS1-441 - Abstract
Vesicular hand eczema (VHE), a clinical subtype of hand eczema (HE), showed limited responsiveness to alitretinoin, the only approved systemic treatment for severe chronic HE. This emphasizes the need for alternative treatment approaches. Therefore, our study aimed to identify drug repurposing opportunities for VHE using transcriptomics and genomics data. We constructed a gene network by combining 52 differentially expressed genes (DEGs) from a VHE transcriptomics study with 3 quantitative trait locus (QTL) genes associated with HE. Through network analysis, clustering, and functional enrichment analyses, we investigated the underlying biological mechanisms of this network. Next, we leveraged drug–gene interactions and retrieved pharmaco-transcriptomics data from the DrugBank database to identify drug repurposing opportunities for (V)HE. We developed a drug ranking system, primarily based on efficacy, safety, and practical and pricing factors, to select the most promising drug repurposing candidates. Our results revealed that the (V)HE network comprised 78 genes that yielded several biological pathways underlying the disease. The drug–gene interaction search together with pharmaco-transcriptomics lookups revealed 123 unique drug repurposing opportunities. Based on our drug ranking system, our study identified the most promising drug repurposing opportunities (e.g., vitamin D analogues, retinoids, and immunomodulating drugs) that might be effective in treating (V)HE.
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- 2024
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41. DEVELOPMENT AND VALIDATION OF UV-VISIBLE SPECTROPHOTOMETRIC METHOD FOR ESTIMATION OF LAMIVUDINE AND ZIDOVUDINE IN BULK AND TABLET DOSAGE FORM
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Lokendra Bhamare*, Sufiyan Ahmad, V. M. Shastry
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Lamivudine And Zidovudine, Method Development, Validation, Simultaneous Estimation, UV Spectroscopy - Abstract
Simple, rapid, sensitive, precise and specific UV spectrophotometric method for the determination of Lamivudine (LAMI) and Zidovudine (ZIDO) in bulk drug and tablet dosage form were developed and validated. A simple double beam UV spectrophotometric method has been developed and validated with different parameters such as linearity, precision, repeatability, limit of detection (LOD), Limit of Quantification (LOQ), accuracy as per ICH guidelines. UV-visible spectrophotometric method, measurement of absorption at maximum wavelength in 10 ml acetonitrile and volume make with water solvent system as reference LAMI and ZIDO were found to be at 271 nm and 262 nm respectively. The drug obeyed the Beer’s law and showed good correlation. Beer’s law was obeyed in concentration range 2-10 μg/ml for LAMI and 1- 5μg/ml for LAMI respectively with correlation coefficient was 0.999. The LOD and LOQ of LAMI were found to be 0.3831(μg/mL) and 1.1609 (μg/ml), ZIDO were found to be 0.6276μg/ml) and 1.9018 (μg/ml), respectively. The proposed method is precise, accurate and reproducible and can be used for routine analysis of LAMI and ZIDO in bulk and tablet dosage form.
- Published
- 2017
- Full Text
- View/download PDF
42. Birth prevalence of genital anomalies among males conceived by intracytoplasmic sperm injection cycles: A cross-sectional study
- Author
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Fatemeh Aliani, Zahra Haghshenas, Ahmad Vosough Dizaj, Arezoo Arabipoor, Samira Vesali, and Mahnaz Ashrafi
- Subjects
cryptorchidism, hypospadias, microinjections, prevalence, reproductive techniques, urogenital abnormalities. ,Gynecology and obstetrics ,RG1-991 ,Reproduction ,QH471-489 - Abstract
Abstract Background: Several studies have been conducted worldwide to evaluate the prevalence and relative risks of congenital anomalies associated with assisted reproductive technology cycles; however, there is limited data in Iran. Objective: To investigate male genital anomalies among live births from assisted reproductive technology. Materials and Methods: This cross-sectional study was conducted on children born after intracytoplasmic sperm injection (ICSI) at Royan Institute, Tehran, Iran from April 2013-December 2015. The prevalence of male genitalia disorders that included hypospadias, epispadias, cryptorchidism, micropenis, and vanishing testis were reported. The relationship between the cause of infertility and type of embryo transfer (fresh or frozen), gestational age at birth (term or preterm), and birth weight with these male genitalia anomalies were evaluated. Results: In total, 4409 pregnant women were followed after their ICSI cycles to evaluate genitalia anomalies in their children. Out of 5608 live births, 2614 (46.61%) newborns were male, of which 14 cases (0.54%) had genital anomalies. The prevalence of various anomalies were cryptorchidism (0.34%), hypospadias (0.038%), micropenis (0.038%), vanishing testis (0.038%), and epispadias (0.077%). No relationship was found between the cause of infertility, type of embryo transfer (fresh or frozen), gestational age at birth (term or preterm), and male genital malformation (p = 0.33, p = 0.66, and p = 0.62, respectively). Conclusion: The prevalence of each male genital anomaly after the ICSI cycle was rare and less than 0.5%; however, no significant infertility-related factor was observed with these anomalies.
- Published
- 2023
- Full Text
- View/download PDF
43. Neuro-nanotechnology: diagnostic and therapeutic nano-based strategies in applied neuroscience
- Author
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Leili Shabani, Milad Abbasi, Zeynab Azarnew, Ali Mohammad Amani, and Ahmad Vaez
- Subjects
Nanotechnology ,Nanoparticles ,Nanomaterials ,Neuroscience ,Medical technology ,R855-855.5 - Abstract
Abstract Artificial, de-novo manufactured materials (with controlled nano-sized characteristics) have been progressively used by neuroscientists during the last several decades. The introduction of novel implantable bioelectronics interfaces that are better suited to their biological targets is one example of an innovation that has emerged as a result of advanced nanostructures and implantable bioelectronics interfaces, which has increased the potential of prostheses and neural interfaces. The unique physical–chemical properties of nanoparticles have also facilitated the development of novel imaging instruments for advanced laboratory systems, as well as intelligently manufactured scaffolds and microelectrodes and other technologies designed to increase our understanding of neural tissue processes. The incorporation of nanotechnology into physiology and cell biology enables the tailoring of molecular interactions. This involves unique interactions with neurons and glial cells in neuroscience. Technology solutions intended to effectively interact with neuronal cells, improved molecular-based diagnostic techniques, biomaterials and hybridized compounds utilized for neural regeneration, neuroprotection, and targeted delivery of medicines as well as small chemicals across the blood–brain barrier are all purposes of the present article.
- Published
- 2023
- Full Text
- View/download PDF
44. Effective treatment of intractable diseases using nanoparticles to interfere with vascular supply and angiogenic process
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Ahmad Hoseinzadeh, Hamed Ghoddusi Johari, Mohammad Hossein Anbardar, Lobat Tayebi, Ehsan Vafa, Milad Abbasi, Ahmad Vaez, Ali Golchin, Ali Mohammad Amani, and Ali Jangjou
- Subjects
Vascularization ,Angiogenesis ,Anti-angiogenic therapy ,Nanoparticles ,Therapeutic applications ,Medicine - Abstract
Abstract Angiogenesis is a vital biological process involving blood vessels forming from pre-existing vascular systems. This process contributes to various physiological activities, including embryonic development, hair growth, ovulation, menstruation, and the repair and regeneration of damaged tissue. On the other hand, it is essential in treating a wide range of pathological diseases, such as cardiovascular and ischemic diseases, rheumatoid arthritis, malignancies, ophthalmic and retinal diseases, and other chronic conditions. These diseases and disorders are frequently treated by regulating angiogenesis by utilizing a variety of pro-angiogenic or anti-angiogenic agents or molecules by stimulating or suppressing this complicated process, respectively. Nevertheless, many traditional angiogenic therapy techniques suffer from a lack of ability to achieve the intended therapeutic impact because of various constraints. These disadvantages include limited bioavailability, drug resistance, fast elimination, increased price, nonspecificity, and adverse effects. As a result, it is an excellent time for developing various pro- and anti-angiogenic substances that might circumvent the abovementioned restrictions, followed by their efficient use in treating disorders associated with angiogenesis. In recent years, significant progress has been made in different fields of medicine and biology, including therapeutic angiogenesis. Around the world, a multitude of research groups investigated several inorganic or organic nanoparticles (NPs) that had the potential to effectively modify the angiogenesis processes by either enhancing or suppressing the process. Many studies into the processes behind NP-mediated angiogenesis are well described. In this article, we also cover the application of NPs to encourage tissue vascularization as well as their angiogenic and anti-angiogenic effects in the treatment of several disorders, including bone regeneration, peripheral vascular disease, diabetic retinopathy, ischemic stroke, rheumatoid arthritis, post-ischemic cardiovascular injury, age-related macular degeneration, diabetic retinopathy, gene delivery-based angiogenic therapy, protein delivery-based angiogenic therapy, stem cell angiogenic therapy, and diabetic retinopathy, cancer that may benefit from the behavior of the nanostructures in the vascular system throughout the body. In addition, the accompanying difficulties and potential future applications of NPs in treating angiogenesis-related diseases and antiangiogenic therapies are discussed.
- Published
- 2022
- Full Text
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45. Tip Speed Ratio Optimization: More Energy Production with Reduced Rotor Speed
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Amir Hosseini, Daniel Trevor Cannon, and Ahmad Vasel-Be-Hagh
- Subjects
wind farm ,tip speed ratio ,wake losses ,optimization ,renewable energy ,wind energy ,Production of electric energy or power. Powerplants. Central stations ,TK1001-1841 - Abstract
A wind turbine’s tip speed ratio (TSR) is the linear speed of the blade’s tip, normalized by the incoming wind speed. For a given blade profile, there is a TSR that maximizes the turbine’s efficiency. The industry’s current practice is to impose the same TSR that maximizes the efficiency of a single, isolated wind turbine on every turbine of a wind farm. This article proves that this strategy is wrong. The article demonstrates that in every wind direction, there is always a subset of turbines that needs to operate at non-efficient conditions to provide more energy to some of their downstream counterparts to boost the farm’s overall production. The aerodynamic interactions between the turbines cause this. The authors employed the well-known Jensen wake model in concert with Particle Swarm Optimization to demonstrate the effectiveness of this strategy at Lillgrund, a wind farm in Sweden. The model’s formulation and implementation were validated using large-eddy simulation results. The AEP of Lillgrund increased by approximately 4% by optimizing and actively controlling the TSR. This strategy also decreased the farm’s overall TSR, defined as the average TSR of the turbines, by 8%, leading to several structural and environmental benefits. Note that both these values are farm-dependent and change from one farm to another; hence, this research serves as a proof of concept.
- Published
- 2022
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46. The relationship between positive organizational behavior and demographic factors of banking industry managers with their communication quotient (Case study: Keshavarzi bank)
- Author
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Sahar Sadraei and Ahmad Vedadi
- Subjects
communication quotient ,positive organizational behavior ,banking industry ,Business records management ,HF5735-5746 ,Economics as a science ,HB71-74 - Abstract
Communication quotient of a manager helps him to adjust his communication style. In this research, the researcher has investigated the positive organizational behavior and demographic factors affecting the communication quotient of managers in the keshavarzi Bank. This research is applied in terms of purpose and descriptive in terms of data collection. The statistical population includes managers, assistants and experts of the keshavarzi bank in the whole of Tehran province in the number of 387 people, and based on Morgan 's table, the sample number was calculated to be 193 people, who were selected using random sampling method. The research tools were the standard psychological capital questionnaires of Luthans et al. (2007) and Burmester 's communication competence (1988). The validity of the questionnaires was confirmed based on face and content validity, 0.893, and Cronbach\'s alpha method was used for the reliability of the questionnaire, and its values were 0.79 for the psychological capital questionnaire and 0.83 for the communicative competency. Data analysis was done at two descriptive and inferential levels using the correlation method. The findings showed that demographic factors and variables of positive organizational behavior have created a positive and significant relationship with communication quotient. But among the personality traits, only gender variable 25 percent and marriage variable 35 percent; And in the dimensions of positive organizational behavior, only the dimension of optimism 30 percent was able to explain the changes in communication quotient.
- Published
- 2022
- Full Text
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47. Comparison of individual versus ensemble wind farm parameterizations inclusive of sub‐grid wakes for the WRF model
- Author
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Yulong Ma, Cristina L. Archer, and Ahmad Vasel‐Be‐Hagh
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Anholt ,Jensen ,Lillgrund ,wake effects ,wake losses ,wind turbine ,Renewable energy sources ,TJ807-830 - Abstract
Abstract Wind turbine wakes can be predicted somewhat accurately with mesoscale numerical models, such as the Weather Research and Forecast (WRF) model, via a wind farm parameterization (WFP) that treats the effects of the wakes, which are sub‐grid features, on power production and the environment. A few WFPs have been proposed in the literature, but none has been able to properly account for the individual wakes within a grid cell or the effects of overlapping wakes from multiple turbines. A solution to these two issues is a WFP that includes both a wake model, which is a simplified analytical model of the wind speed (or wind power) deficit caused by a wake, and a wake superposition model, which accounts for overlapping wakes. Several such WFPs are developed here for the WRF model—based on the Jensen, the Geometric, and the Gaussian wake models coupled with two wake superposition methods (based on a squared deficit and a squared velocity superposition)—and tested individually, as well as combined together in an ensemble (EWFP), at two modern offshore wind farms. Most WFPs perform satisfactorily alone, but the EWFP generally outperforms them at both farms. The issue of resolved versus sub‐grid wakes is explored for single‐ and multi‐cell cases and for directions of alignment and non‐alignment between the wind direction and the turbine columns. Although different combinations of wake loss and wake superposition models might be preferred at other wind farms, the general findings and detailed performance statistics given here might provide useful guidance in their selection.
- Published
- 2022
- Full Text
- View/download PDF
48. Antimicrobial Potential of Methanolic Extract and Various Fractions of Jatropha curcas Roots
- Author
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Anwar, S., Zubair, M., Umer Rashid, Rizwan, K., Shahid, M., Bukhari, I. H., Jamil, M., Ahmad, V. U., and Rasool, N.
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General Chemistry - Published
- 2013
49. Erratum to: Nuclear Proteome Analysis of Monkey Embryonic Stem Cells During Differentiation
- Author
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Nasrabadi, Davood, Larijani, Mehran Rezaei, Fathi, Ali, Gourabi, Hamid, Dizaj, Ahmad V., Baharvand, Hossein, and Salekdeh, Ghasem Hosseini
- Published
- 2010
- Full Text
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50. Chemical Constituents from Erigeron bonariensis L. and their Chemotaxonomic Importance
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Zahoor, A., Hidayat Hussain, Khan, A., Ahmed, I., Ahmad, V. U., and Krohn, K.
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lcsh:Chemistry ,lcsh:QD241-441 ,lcsh:QD1-999 ,lcsh:Organic chemistry ,natural products ,lcsh:Botany ,chemotaxonomic studies ,Erigeron bonariensis ,lcsh:QK1-989 - Abstract
The study of the chemical constituents of the whole plant of Erigeron bonariensis (L.) has resulted in the isolation and characterization of a new and nine known compounds. The known compounds were identified as stigmasterol (1), freideline (2), 1, 3-dihydroxy-3R,5R-dicaffeoyloxy cyclohexane carboxylic acid methyl ester (3),1 R ,3R-dihydroxy-4S,5R-dicaffeoyloxycyclohexane carboxylic acid methyl ester (4), quercitrin (5), caffeic acid (6), 3-(3,4-dihydroxyphenyl)acrylic acid 1-(3,4-dihydroxyphenyl)-2-methoxycarbonylethyl ester (8), benzyl O-β-D-glucopyranoside (9), and 2-phenylethyl-β-D-glucopyranoside (10). The aromatic glycoside, erigoside G (7) is reported as new natural compound. The above compounds were individually identified by spectroscopic analyses and comparisons with reported data. The chemotaxonomic studies of isolated compounds have been discussed.
- Published
- 2012
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