1
|
Mokammel A, Rostami R, Niazi S, Asgari A, Fazlzadeh M. BTEX levels in rural households: Heating system, building characteristic impacts and lifetime excess cancer risk assessment. Environ Pollut 2022; 298:118845. [PMID: 35031402 DOI: 10.1016/j.envpol.2022.118845] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/2021] [Revised: 01/07/2022] [Accepted: 01/09/2022] [Indexed: 06/14/2023]
Abstract
BTEX (benzene, toluene, ethylbenzene, and xylene) are a group of toxic organic compounds that exposure to them can cause adverse short and long terms health effects. We measured the levels of BTEX in the indoor and outdoor air of rural areas in Ardebil, Iran. We further assessed their health risks and determinants parameters. BTEX were sampled by drawing air through activated charcoal tubes, using low flow SKC pumps. Samples were extracted by adding carbon disulfide and analyzed by subjecting the aromatic fraction to GC-FID. The results indicated that the concentrations of BTEX in the indoor air were significantly higher than those of outdoor (p-value<0.05). The mean indoor concentrations of benzene, toluene, ethylbenzene, and xylene were 41.69 ± 30.70, 96.73 ± 60.75, 38.73 ± 33.59, and 59.42 ± 35.99 μg m-3, while the mean outdoor concentrations of them were 8.94 ± 7.32, 36.93 ± 21.82, 7.66 ± 5.63, and 18.14 ± 10.25 μg m-3, respectively. The concentrations of BTEX in indoor and outdoor of the rural areas that used kerosene fuel for heating systems were significantly higher than those used natural gas. The results indicated that the tobacco smoke is a notable temporary source of indoor BTEX. The mean inhalation lifetime cancer risk (LTCR) value of benzene for residents of rural houses with the natural gas and kerosene heating systems were 28.6 × 10-6 and 97.2 × 10-6, while for ethylbenzene these figures stood out at 29.1 × 10-6 and 95.8 × 10-6, respectively. LTCR value for residents who used kerosene fuel for heating was higher than the World Health Organization (WHO) recommended limit.
Collapse
Affiliation(s)
- Adel Mokammel
- Department of Environmental Health Engineering, School of Public Health, Khalkhal University of Medical Sciences, Khalkhal, Iran
| | - Roohollah Rostami
- Research Center for Health Sciences and Technologies, Semnan University of Medical Sciences, Semnan, Iran
| | - Sadegh Niazi
- Queensland University of Technology (QUT), Faculty of Science, School of Earth and Atmospheric Sciences, International Laboratory for Air Quality and Health (ILAQH), Brisbane, 4001, Australia
| | - Amin Asgari
- Department of Environmental Health Engineering, School of Public Health, Khalkhal University of Medical Sciences, Khalkhal, Iran
| | - Mehdi Fazlzadeh
- Social Determinants of Health Research Center, Ardabil University of Medical Sciences, Ardabil, Iran.
| |
Collapse
|
2
|
Maddahi A, Bani Hani J, Asgari A, Nassiri AM, Choukou MA. Therapists' perspectives on a new portable hand telerehabilitation platform for home-based personalized treatment of stroke patients. Eur Rev Med Pharmacol Sci 2021; 25:5790-5800. [PMID: 34604970 DOI: 10.26355/eurrev_202109_26797] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
OBJECTIVE Patients who have sustained a stroke suffer from residual motor impairments. Stroke can limit their ability to employ their impaired upper limb properly. Hand function is particularly one of the most frequently persisting consequences of stroke. This paper introduces a new portable hand telerehabilitation platform (PHTP) for home-based personalized treatment of stroke patients. The aims of this study are (1) to document the iterative design and development process of the PHTP, and (2) to explore the therapists' perspectives on implementing home-based treatment of stroke patients. MATERIALS AND METHODS Local therapists were involved early in designing and developing the PHTP. We collected views of 84 therapists practicing in North America via an online survey. RESULTS Therapists' perspectives on the introduced prototype support the use of the PHTP to provide home-based telerehabilitation for stroke patients. The System Usability Scale score was 70 for the PHTP, indicating that the platform is usable. The rest of the qualitative results obtained from custom questionnaires showed consistency in the platform design, high perceived usability and good acceptability among the therapists' community. CONCLUSIONS In sum, the results encourage and support fine-tuning of the PHTP, commercializing it, and conducting prospective clinical studies.
Collapse
Affiliation(s)
- A Maddahi
- Department of Occupational Therapy, College of Rehabilitation Sciences, University of Manitoba, Winnipeg (MB), Canada.
| | | | | | | | | |
Collapse
|
3
|
Bao X, Asgari A, Najafi ML, Mokammel A, Ahmadi M, Akbari S, Miri M. Exposure to waterpipe smoke and blood heavy metal concentrations. Environ Res 2021; 200:111460. [PMID: 34089744 DOI: 10.1016/j.envres.2021.111460] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2021] [Revised: 05/28/2021] [Accepted: 05/31/2021] [Indexed: 06/12/2023]
Abstract
Waterpipe (WP) smoking is a global phenomenon, with the most consumers in Middle East countries and China. Heavy metals exposure related to WP smoking has been associated with many adverse health effects. However, the association of lifestyle factors and smoking habits with blood heavy metals concentration in WP smokers is unclear yet. Therefore, we aimed to investigate the relationship of lifestyle factors (i.e., diet and physical activity) and smoking habits (i.e., duration of the use of WP and times of smoking WP per week) with blood concentrations of lead (Pb) and cadmium (Cd). This cross-sectional study was based on 86 WP smokers in Khalkhal, Iran (2018). Graphite furnace atomic absorption spectrometry (GFAAS) was used to measure heavy metals. The median (interquartile range (IQR)) of Pb and Cd concentrations were 39 (24) and 1.3 (1.2) μg/L. The blood Pb and Cd levels were significantly higher in participants with lower education level (P-value = 0.049 and 0.041, respectively). An IQR increase in physical activity per week was associated with -0.12 μg/L (95% confidence interval (CI): -0.23, -0.01, P-value = 0.04) decrease in Pb concentration. An increase in the times of consuming fruit per week was negatively associated with the concentration of Cd. Overall, our findings suggested that physical activity and healthy diet have been associated with lower blood heavy metal concentrations in WP smokers; however, further studies are needed to confirm these findings.
Collapse
Affiliation(s)
- Xianghua Bao
- Department of Occupational Disease, Yantai Shan Hospital, (Yantai Occupational Disease Hospital), NO. 167 Airport Road, Zhifu District, Yantai City, Shandong Province, 264025, China
| | - Amin Asgari
- Department of Environmental Health Engineering, Khalkhal University of Medical Sciences, Khalkhal, Iran; Sharifsafetyindex, Health, Safety, Environment Service, Co, Iran.
| | - Moslem Lari Najafi
- Pharmaceutical Sciences and Cosmetic Products Research Center, Kerman University of Medical Sciences, Kerman, Iran
| | - Adel Mokammel
- Department of Environmental Health Engineering, Khalkhal University of Medical Sciences, Khalkhal, Iran
| | - Mohammad Ahmadi
- Student Research Committee, Khalkhal University of Medical Sciences, Khalkhal, Iran
| | - Sajjad Akbari
- Student Research Committee, Khalkhal University of Medical Sciences, Khalkhal, Iran
| | - Mohammad Miri
- Non-Communicable Diseases Research Center, Department of Environmental Health, School of Public Health, Sabzevar University of Medical Sciences, Sabzevar, Iran.
| |
Collapse
|
4
|
Shoja E, Aghamohammadi V, Bazyar H, Moghaddam HR, Nasiri K, Dashti M, Choupani A, Garaee M, Aliasgharzadeh S, Asgari A. Covid-19 effects on the workload of Iranian healthcare workers. BMC Public Health 2020; 20:1636. [PMID: 33138798 PMCID: PMC7605333 DOI: 10.1186/s12889-020-09743-w] [Citation(s) in RCA: 84] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2020] [Accepted: 10/21/2020] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND In this study, we aimed to evaluate the impact of the COVID-19 epidemic on the workload and mental health of Iranian medical staff using the General Health Questionnaire (GHQ-12) and NASA -Task Load Index (NASA-TLX) Questionnaire between March and April 2020, respectively. METHODS The present cross-sectional study was conducted from March 5th to April 5th, 2020. To evaluate the workload and mental health of participants NASA-TLX and GHQ-12 online questionnaires were distributed. Data were entered into software SPSS (Version 23) and T-test, ANOVA, Regression methods were used for data analysis. RESULTS Health workers who encountered COVID- 19 patients, were subjected to more task load compared to those who had no contact with COVID- 19 patients at the workplace (p < 0.001). In terms of the subscale score of NASA-TLX, nurses had more scores in mental pressure, physical pressure, time pressure (temporal), and frustration compared to the other jobs (p < 0.05). Moreover, nurses had significantly more workload compared to the other jobs. CONCLUSIONS Type of job, the shift of work, educational level, and facing COVID-19 affected the score of NASA-TLX. NASA-TLX scores were higher in nursing compared to the scores of other health staff groups. The results of this study indicate that the scores of NASA-TLX and GHQ-12 among staff who had contact with COVID-19 patients were significantly higher than those who did not face COVID-19 patients. We suggested that a comprehensive assistance should be provided to support the well-being of healthcare workers especially nurses and healthcare workers who treated COVID-19 patients.
Collapse
Affiliation(s)
- Esmail Shoja
- School of Medical Sciences Esfarayen Faculty of Medical Sciences, Esfarayen, Iran
| | | | - Hadi Bazyar
- Student Research Committee, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
| | | | - Khadijeh Nasiri
- Department of Nursing, Khalkhal University of Medical Sciences, Khalkhal, Iran
| | | | - Ali Choupani
- School of Medical Sciences Esfarayen Faculty of Medical Sciences, Esfarayen, Iran
| | - Masoumeh Garaee
- School of Medical Sciences Esfarayen Faculty of Medical Sciences, Esfarayen, Iran
| | - Shafagh Aliasgharzadeh
- Department of Internal Medicine, School of Medicine and Allied Medical Sciences, Imam Khomeini Hospital, Ardabil University of Medical Sciences, Ardabil, Iran
| | - Amin Asgari
- Department of Environmental Health, Khalkhal University of Medical Sciences, Khalkhal, Iran.
| |
Collapse
|
5
|
Asgari A, Parach AA, Mirmohammadi SJ, Mehrparvar AH, Daneshian E, Nekoofar Z. Investigating the effective annual dose of radiation angiography department of Afshar Hospital in Yazd and providing radiation protection strategies to better manage the dose received by staff. Occup Med (Lond) 2020. [DOI: 10.18502/tkj.v12i1.3657] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Introduction: Due to the increasing use of angiography procedures and the higher risk of deterministic and stochastic effects for radiation workers of these sections than other radiological procedures, radiation safety is very important among angiography staff. Therefore, this study aimed to obtain the effective dose of angiography staff, compare them with the standard dose limit, and finally outline the strategies for occupational dose reduction in angiography.
Methods: In this study, the report of film dosimetry of angiography staff was studied and the effective periodic and annual doses of 34 radiographs were reported from the year 2015 to 2018. The relationship between effective dose and body mass index, work experience, gender and age of staff was also evaluated.
Results: The results showed that the average effective dose of the physicians, nurses and radiographers in 2 months period were 0.2 mSv and their average annual effective dose were 1.6, 1.2 and 1.2, respectively. In addition, there were no significant relationship between effective dose and work experience, age, sex and BMI of the radiation workers.
Conclusion: The effective dose of radiation in this study is less than the annual dose.. Low effective doses do not make their radiation protection less important because this reduction can be due to radiation protection by personnel in this ward. Therefore, as far as possible, radiation protection measures should be taken to reduce the radiation exposure of catheterization lab staff. In these radiologists thyroid protection, eyes, gonads, and the organs that are usually outside the lead apron is of great importance.
Collapse
|
6
|
Affiliation(s)
- A Esmaeili
- Department of Chemical Engineering, North Tehran Branch, Islamic Azad University, PO Box 19585/936, Tehran, Iran, Tehran, Iran
| | - A Asgari
- Department of Chemical Engineering, North Tehran Branch, Islamic Azad University, PO Box 19585/936, Tehran, Iran, Tehran, Iran
| |
Collapse
|
7
|
Kashiri M, Asgari A. Modeling of carrier dynamics in InGaAs/GaAs self-assembled quantum dot lasers. Appl Opt 2016; 55:2042-2048. [PMID: 26974800 DOI: 10.1364/ao.55.002042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
In this study, a theoretical model is used to simulate the lasing characteristics of InGaAs/GaAs self-assembled quantum dot lasers. The rate equation for InGaAs/GaAs is numerically solved using the fourth-order Runge-Kutta method. We consider the homogeneous and inhomogeneous broadening of the optical gain, both with and without considering the nonlinear gain. The results indicate that for a certain injected current, there is a specific homogeneous broadening (HB) with the best lasing performance when HB is near, comparable, or equal to inhomogeneous broadening for every laser-injected current. We show that if the linear optical gain is replaced by the total gain, the output power will reduce a little and the peaks will be more broadened and the maximum of the gain spectrum decreases. The time evolution of the photon number for different currents and different HBs is shown. The results indicate that by increasing the HB, the number of photons in the steady state and the delay in the starting oscillation will increase. In addition, we show that there is threshold coverage for quantum dots to begin lasing and an optimum quantum dot coverage in which the self-assembled quantum dot lasers operate with the lowest possible threshold current and maximum output power.
Collapse
|
8
|
Tahmasebpour M, Bahrami M, Asgari A. Investigation of subwavelength grating structure for enhanced surface plasmon resonance detection. Appl Opt 2014; 53:6307-6316. [PMID: 25322112 DOI: 10.1364/ao.53.006307] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2014] [Accepted: 08/18/2014] [Indexed: 06/04/2023]
Abstract
A metallic subwavelength grating structure built on a thin gold film is studied for surface plasmon resonance (SPR) detection of refractive index variations of biological buffer solutions. By employing finite element analysis as a numerical method, characteristics of the angle interrogated SPR sensor were calculated and discussed in a broad operating wavelength varying from visible to near-infrared (NIR). The effects of grating structural parameters such as grating depth, grating period, and grating fill factor in different operating wavelengths have been evaluated on the sensor performance parameters of sensitivity, full width at half-minimum, minimum reflectance at resonance, and resonance angle. Numerical results indicate that adjusting grating geometrical parameters can enhance the performance parameters of the sensor especially in the NIR wavelengths. The enhanced sensor performance parameters for optimizing grating geometry have been explored in detail for visible and NIR wavelengths of 633 and 984 nm, respectively. These findings are important for developing localized surface plasmon sensors with enhanced performance.
Collapse
|
9
|
Asgari A, Dianatirad M, Ranjbaran M, Sadeghi A, Rahimpour M. Methanol treatment in gas condensate reservoirs: A modeling and experimental study. Chem Eng Res Des 2014. [DOI: 10.1016/j.cherd.2013.08.015] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
|
10
|
Tahmasebpour M, Bahrami M, Asgari A. Design study of nanograting-based surface plasmon resonance biosensor in the near-infrared wavelength. Appl Opt 2014; 53:1449-58. [PMID: 24663375 DOI: 10.1364/ao.53.001449] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2013] [Accepted: 01/27/2014] [Indexed: 05/26/2023]
Abstract
A key issue with surface plasmon resonance (SPR) biosensors, which are the focus of many researchers, is improving their sensitivity to detect lower amounts of analyte in a solution. Most SPR developments have focused on the grating-based sensitivity-enhancement approach. In addition to sensitivity, a substantial enhancement of other sensor characteristics such as resolution and signal-to-noise ratio (SNR) is desired for designing a practical sensor. So, in this paper, the characteristics of surface plasmon polaritons sustained by 1D subwavelength metallic gratings on a thin metal slab (under the Krestchmann configuration) have been investigated numerically for the analyte-ligand interactions detection. Effects of different structural parameters, such as grating period, grating depth, metal film thickness, and fill factor have been evaluated on the sensor sensitivity as well as resolution and SNR. Numerical results indicate that the sensor working in the near-infrared wavelength has a better performance than that in the visible one. The result of numerical investigation has been used to design an optimized sensor with the best figure of merit.
Collapse
|
11
|
Bahrami F, Hashemi M, Khalili F, Hashemi J, Asgari A. Stimulation of CB1 Cannabinoid and NMDA Receptors Increases Neuroprotective Effect against Diazinon-Induced Neurotoxicity. NEUROPHYSIOLOGY+ 2013. [DOI: 10.1007/s11062-013-9390-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
|
12
|
Naghii M, Ghanizadeh G, Darvishi P, Ebrahimpour Y, Mofid M, Torkaman G, Asgari A, Hedayati M. Whole body vibration is a safe exercise training method and induces no impaired alterations on rat plasma parameters. ACTA ACUST UNITED AC 2011; 98:442-8. [DOI: 10.1556/aphysiol.98.2011.4.7] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
|
13
|
Bandarian M, Ghanbari Z, Asgari A. Comparison of transobturator tape (TOT) vs Burch method in treatment of stress urinary incontinence. J OBSTET GYNAECOL 2011; 31:518-20. [DOI: 10.3109/01443615.2011.578776] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
|
14
|
|
15
|
Asgari A, Razi S. High performances III-Nitride Quantum Dot infrared photodetector operating at room temperature. Opt Express 2010; 18:14604-14615. [PMID: 20639946 DOI: 10.1364/oe.18.014604] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
In this paper we present a novel long wave length infrared quantum dot photodetector. A cubic shaped 6nm GaN quantum dot (QD) within a large 18 nm Al(0.2)Ga(0.8)N QD (capping layer) embedded in Al(0.8)Ga(0.2)N has been considered as the unit cell of the active layer of the device. Single band effective mass approximation has been applied in order to calculate the QD electronic structure. The temperature dependent behavior of the responsivity and dark current were presented and discussed for different applied electric fields. The capping layer has been proposed to improve upon the dark current of the detector. The proposed device has demonstrated exceptionally low dark current, therefore low noise, and high detectivity. Excellent specific detectivity (D*) up to approximately 3 x 10(8)CmHz(1/ 2)/W is achieved at room temperature.
Collapse
Affiliation(s)
- A Asgari
- Photonics-Electronics Group, Research Institute for Applied Physics, University of Tabriz, Tabriz 51665-163, Iran.
| | | |
Collapse
|
16
|
Bahrami F, Yousefpour M, Mehrani H, Golmanesh L, Sadraee SH, Khoshbaten A, Asgari A. Type of cell death and the role of acetylcholinesterase activity in neurotoxicity induced by paraoxon in cultured rat hippocampal neurons. Acta Biol Hung 2009; 60:1-13. [PMID: 19378919 DOI: 10.1556/abiol.60.2009.1.1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Organophosphate (Ops) neurotoxicity is attributed both to its well-known cholinergic and non-cholinergic effects. In the present study we compared enzymatic and morphologic changes in neurons exposed to paraoxon during one day and one week. The effect of exposure time is important in neurotoxicity of Ops. The longer the exposure time is the more damage is observed in neurons, although there are few investigations about the effect in the post-exposure period. Hippocampal cells were obtained from rat neonates and cultured in Neurobasal/B27. Paraoxon at 50 and 100 microM were added. Inverted microscope and electron microscope were used to study cell morphology and Neutral Red staining was used to measure viability. We also assayed caspase-3 and (acetylcholinesterase) AChE activity. Hoechst staining was utilized to determine the type of cell death. Culture medium was replaced after 24 h in one-day group, however, tests were all carried out at the end of the first week in both group. The results indicate that paraoxon reduced the viability in a dose-dependent manner. Our results do not confirm apoptosis in either group; it seems that the cell death in one-day exposure group was not AChE dependent. In conclusion, present data imply that the toxicity of paraoxon is both dose and duration dependent, which may even remain after the cessation of exposure.
Collapse
Affiliation(s)
- F Bahrami
- Department of Physiology and Biophysics, Baqyatallah University of Medical Science, Tehran, Iran
| | | | | | | | | | | | | |
Collapse
|
17
|
Rahimpour MR, Asgari A. Modeling and simulation of ammonia removal from purge gases of ammonia plants using a catalytic Pd-Ag membrane reactor. J Hazard Mater 2008; 153:557-565. [PMID: 17936505 DOI: 10.1016/j.jhazmat.2007.08.095] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/04/2007] [Revised: 08/29/2007] [Accepted: 08/30/2007] [Indexed: 05/25/2023]
Abstract
In this work, the removal of ammonia from synthesis purge gas of an ammonia plant has been investigated. Since the ammonia decomposition is thermodynamically limited, a membrane reactor is used for complete decomposition. A double pipe catalytic membrane reactor is used to remove ammonia from purge gas. The purge gas is flowing in the reaction side and is converted to hydrogen and nitrogen over nickel-alumina catalyst. The hydrogen is transferred through the Pd-Ag membrane of tube side to the shell side. A mathematical model including conservation of mass in the tube and shell side of reactor is proposed. The proposed model was solved numerically and the effects of different parameters on the rector performance were investigated. The effects of pressure, temperature, flow rate (sweep ratio), membrane thickness and reactor diameter have been investigated in the present study. Increasing ammonia conversion was observed by raising the temperature, sweep ratio and reducing membrane thickness. When the pressure increases, the decomposition is gone toward completion but, at low pressure the ammonia conversion in the outset of reactor is higher than other pressures, but complete destruction of the ammonia cannot be achieved. The proposed model can be used for design of an industrial catalytic membrane reactor for removal of ammonia from ammonia plant and reducing NO(x) emissions.
Collapse
Affiliation(s)
- M R Rahimpour
- Department of Chemical and Petroleum Engineering, College of Engineering, Shiraz University, Shiraz, Iran.
| | | |
Collapse
|
18
|
Naghdi S, Ansari NN, Mansouri K, Olyaei GR, Asgari A, Kazemnejad A. The correlation between Modified Ashworth Scale scores and the new index of alpha motoneurones excitability in post-stroke patients. Electromyogr Clin Neurophysiol 2008; 48:109-15. [PMID: 18435215 DOI: pmid/18435215] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
The Modified Ashworth Scale (MAS) is currently a widely used clinical scale to evaluate muscle spasticity. However, it lacks reliability and the validity, of the MAS as a clinical measure of muscle spasticity has been challenged. The aim of the present study was to examine the validity of the MAS in patients with wrist flexor spasticity after stroke by using the Hslope/Mslope (Hslp/Mslp) ratio as the new index of alpha motoneuron excitability. Twenty-seven adult patients (14 women and 13 men) with first ever stroke resulting in hemiplegia with a mean (SD, range) age of 57.9 (11.6, 37-75) were included in the study. The main outcome measures were the MAS for the clinical assessment of spasticity, and the Hslp/Mslp for the neurophysiological evaluation. There was not a significant correlation between the MAS scores and Hslp/Mslp ratio (r = 0.38, p > 0.05). The mean of the Hslp/Mslp did not show a hierarchical increase with the MAS scores. The findings indicate that the MAS is not a valid and ordinal level measure of muscle spasticity.
Collapse
Affiliation(s)
- S Naghdi
- Faculty of Rehabilitation, Medical Sciences University of Tehran, Iran.
| | | | | | | | | | | |
Collapse
|
19
|
Naghdi S, Ansari NN, Mansouri K, Asgari A, Olyaei GR, Kazemnejad A. Neurophysiological examination of the Modified Modified Ashworth Scale (MMAS) in patients with wrist flexor spasticity after stroke. Electromyogr Clin Neurophysiol 2008; 48:35-41. [PMID: 18338533 DOI: pmid/18338533] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
The Modified Modified Ashworth Scale (MMAS) is a clinical test for the measurement of spasticity. The aim of the present study was to examine the validity of the MMAS in patients with wrist flexor spasticity after stroke. 27 adult patients (14 women and 13 men) with first ever stroke resulting in hemiplegia with a mean (SD, range) age of 57.9 (11.6, 37-75) were included in the study. The outcome measures were the MMAS for the clinical assessment of spasticity, the Hslope/Mslope (Hslp/Mslp), and the H(max)/M(max) ratio for the neurophysiological evaluation. The mean of the Hslp/Mslp and the H(max)/M(max) were higher in patients with worse MMAS grades but the differences were not statistically significant. There was a significant positive correlation between the MMAS scores and Hslp/Mslp ratio as the new index of alpha motoneurone excitability or traditional index of H(max)/M(max) ratio (r = 0.39, p = 0.04). It is concluded that the MMAS to be a valid measure of spasticity after stroke.
Collapse
Affiliation(s)
- S Naghdi
- Rehabilitation faculty, Medical Sciences, University of Tehran, Iran.
| | | | | | | | | | | |
Collapse
|
20
|
Naghdi S, Ebrahimi I, Asgari A, Olyaei GR, Kazemnejad A, Mansouri K, Ansari NN. A preliminary study into the criterion validity of the Modified Modified Ashworth Scale using the new measure of the alpha motoneuron excitability in spastic hemiplegia. Electromyogr Clin Neurophysiol 2007; 47:187-92. [PMID: 17557652 DOI: pmid/17557652] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
The Modified Ashworth Scale (MAS) is the most widely used clinical test for the measurement of muscle spasticity. This scale that suffers from limitations and lack of reliability and validity has recently been remodified. The aim of the present study is to investigate the criterion validity of the new Modified MAS(MMAS) in the upper limb in post-stroke hemiplegia, using the Hslope/Mslope (Hslp/Mslp) as a novel index of alpha motor neuron excitability. Prior to the validity study, the reliability of the MMAS was evaluated in 30 hemiplegic patients. The raters agreed on 23 patients (0. 76%). The MMAS had good inter-rater reliability (K= 0.63, SE = 0.11, p < 0.001) for the assessment of wrist flexors spasticity in hemiplegic patients. 12 adult patients (7 women and 5 men) with first ever stroke resulting in hemiplegia with a mean age of 58.9 +/- 11.9 years (range, 37-73) were included in the validity study. The outcome measures were the MMAS for the clinical assessment of spasticity, and the HslopelMslope and the Hmax/Mmax ratio for the electrophysiological evaluation. The results showed an increase in mean rank of Hslp / Mslp in patients with a score of 1, 2 or 3 on the MMAS. However, the difference among the groups was not significant (p > 0.05). There was also no relationship between the clinical scale of MMAS and either the traditional [Hmax / Mmax ratio (r = -0.06)] or the new index [Hslp / Mslp (r = 0.24)] of spinal excitability. This preliminary study recruited a small number of patients, and failed to confirm a linear correlation between these variables. A study with a large number of patients is suggested to clarify the outcome.
Collapse
Affiliation(s)
- S Naghdi
- Rehabilitation faculty, Tehran University of Medical Sciences, Iran.
| | | | | | | | | | | | | |
Collapse
|
21
|
Asgari A, Kalafi M. The control of two-dimensional-electron-gas density and mobility in AlGaN/GaN heterostructures with Schottky gate. Materials Science and Engineering: C 2006. [DOI: 10.1016/j.msec.2005.09.002] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
|
22
|
Yousefpour M, Bahrami F, Shahsavan Behboodi B, Khoshbaten A, Asgari A. Paraoxon-induced ultrastructural growth changes of rat cultured hippocampal cells in neurobasal/B27. Toxicology 2005; 217:221-7. [PMID: 16289293 DOI: 10.1016/j.tox.2005.09.018] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2005] [Revised: 09/29/2005] [Accepted: 09/29/2005] [Indexed: 12/01/2022]
Abstract
Organophosphates (OPs) neurotoxicity is attributed both to their well-known cholinergic and recently attended non-cholinergic effects. Since parathion has been observed to be responsible for more cases of poisoning than any other OP insecticides, it is vitally important to investigate other mechanisms, besides cholinesterase inhibition, which can potentially contribute to the neurotoxicity of parathion (or its metabolite, paraoxon). In present study, hippocampal cells obtained from Wistar rat neonates were cultured in neurobasal medium supplemented with B27 serum where different doses of paraoxon were also introduced. The neuronal growth in the control group and those exposed to paraoxon was compared. Phase contrast microscopy, cell staining (Neutral Red) and computer assessment morphometric study (Motic) were used to study cell morphology, viability and type of cell death. Statistical analysis was carried out using one-way ANOVA. There was no clear morphologic differences between neurons in the control group and those exposed to 10 microM paraoxon; however, deformity of the soma was clear in pellets containing higher concentration of paraoxon. Ultrastructure of cells was markedly altered at 50 microM dose of paraoxon as evidenced by gradual discontinuation of cytoplasm, appearing of numerous vacuoles and intracytoplasmic myelin figure. The processes (neurites) did not grow in media containing 100 microM paraoxon or more. Viability decreased with increasing paraoxon especially above 100 microM. In conclusion, the present data reveal that paraoxon, in 30 microM or higher concentrations, induces a decrease in cell growth, followed by cell swelling and neuronal death (possibly necrosis).
Collapse
Affiliation(s)
- M Yousefpour
- Research Center for Chemical Injuries, Baqiyatallah University of Medical Science, Tehran, Iran.
| | | | | | | | | |
Collapse
|
23
|
Sahraei H, Pirzadeh-Jahromi G, Noorbakhshnia M, Asgari A, Haeri-Rohani A, Khoshbaten A, Poorheidari GR, Sepehri H, Ghoshooni H, Zarrindast MR. Involvement of nucleus accumbens in L-arginine-induced conditioned place preference in rats. Behav Pharmacol 2005; 15:473-80. [PMID: 15472569 DOI: 10.1097/00008877-200411000-00003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
In the present study, the effects of intraperitoneal, intra-accumbal and intra-ventral tegmental area administration of L-arginine and N(G)-nitro-L-arginine methyl-ester (L-NAME) on conditioned place preference behavior were studied. Intraperitoneal (i.p.; 0.5, 1 and 5 mg/kg) and intra-accumbal (intra-NAc; 0.3, 1 and 3 microg/rat), but not intra-ventral tegmental area (intra-VTA; 0.3, 1 and 3 microg/rat) administrations of L-arginine produced a significant place conditioning. Similar injections of L-NAME did not produce any response. However, intraperitoneal pretreatment of the animals with L-NAME (5, 10 and 20 mg/kg), 30 min before L-arginine administration, significantly abolished the acquisition of place conditioning induced by either intraperitoneal or intra-accumbal injection of L-arginine. Moreover, injection of L-NAME (5, 10 and 20 mg/kg) on the test day did not alter the L-arginine response. The results may indicate that L-arginine induces conditioned place preference via an increase in nitric oxide (NO) in the nucleus accumbens.
Collapse
Affiliation(s)
- H Sahraei
- Department of Physiology and Biophysics, Baghyatallah (a.s.) University of Medical Sciences, Niavaran, Tehran, Iran.
| | | | | | | | | | | | | | | | | | | |
Collapse
|
24
|
Zarghi A, Dadashzadeh S, Asgari A. Determination of cyproterone acetate in plasma samples by high-performance liquid chromatography. Boll Chim Farm 2003; 142:220-2. [PMID: 14526655] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/27/2023]
Abstract
A rapid and sensitive high-performance liquid chromatographic method for the determination of cyproterone acetate in human plasma has been developed. The chromatographic separation was performed on an analytical mbondapak C8 column (125 yen 4.6 mm, i.d) with an isocratic mobile phase consisting of methanol-water (62.38 v/v). Using ultra violet detection at 282 nm, the detection limit for cyproterone acetate in plasma was 10 ng/ml. The calibration curve was linear over the concentration range 50-160. 0 ng/ml. Cyproterone was isolated from plasma by liquid-liquid extraction and the recovery was about 90% for plasma. The inter-day and intra-day assay coefficients of variation were found to be less than 10%.
Collapse
Affiliation(s)
- A Zarghi
- Department of Pharmaceutical Chemistry, School of Pharmacy, Shaheed Beheshti University of Medical Sciences, Tehran, Iran
| | | | | |
Collapse
|