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Pollen morphology of Quercus (subgenus Quercus, section Quercus) in Iran and its systematic implication
Parisa Panahi,Mohammad R. Pourmajidian,Asghar Fallah,Mehdi Pourhashemi
Acta Societatis Botanicorum Poloniae , 2012, DOI: 10.5586/asbp.2012.005
Abstract: For the first time, pollen morphology of 9 (4 spp. and 5 subspp.) taxa representing lobed leaved oaks of Iran in the family of Fagaceae has been examined and illustrated using light microscopy and scanning electron microscopy of acetolysed material. Detailed pollen morphological characteristics are given for Quercus section. The pollen grains are single, isopolar, radially symmetrical, tricolpate, tricolporoidate or tricolporate. Pollens were studied to show all possible characteristics like shape, size, apertures, wall thickness, etc., with special reference to the specific features of each pollen type such as structural, sculptural and suprasculptural patterns. There is considerable variation in pollen morphology between taxa so that, three types of pollen shape, five types of structural pattern, two types of sculptural pattern, five types of suprasculptural pattern and three types of perfora distribution are defined. Furthermore, the relationship between pollen morphology and taxonomy is discussed. Overall, pollen characters are shown to be a useful and informative tool for assessing taxonomic position within Quercus section in Iran.
Foliar epidermis morphology in Quercus (subgenus Quercus, section Quercus) in Iran
Parisa Panahi, , Ziba Jamzad, Mohammad R. Pourmajidian, Asghar Fallah, Mehdi Pourhashemi
Acta Botanica Croatica , 2012, DOI: 10.2478/v10184-010-0029-y
Abstract: The foliar morphology of trichomes, epicuticular waxes and stomata in Quercus cedrorum, Q. infectoria subsp. boissieri, Q. komarovii, Q. longipes, Q. macranthera, Q. petraea subsp. iberica and Q. robur subsp. pedunculiflora were studied by scanning electron microscopy. The trichomes are mainly present on abaxial leaf surface in most species, but rarely they appear on adaxial surface. Five trichome types are identified as simple uniseriate, bulbous, solitary, fasciculate and stellate. The stomata of all studied species are of the anomocytic type, raised on the epidermis. The stomata rim may or may not be covered with epicuticular. The epicuticular waxes are mostly of the crystalloid type but smooth layer wax is observed in Q. robur subsp. pedunculiflora. Statistical analysis revealed foliar micromorphological features as been diagnostic characters in Quercus.
Foliar epidermis morphology in Quercus (subgenus Quercus, section Quercus) in Iran
Fallah, Ashgar,Jamzad, Ziba,Panahi, Parisa,Pourhashemi, Mehdi,Pourmajidian, Mohammad R.
- , 2012,
Abstract: Sa？etak The foliar morphology of trichomes, epicuticular waxes and stomata in Quercus cedrorum, Q. infectoria subsp. boissieri, Q. komarovii, Q. longipes, Q. macranthera, Q. petraea subsp. iberica and Q. robur subsp. pedunculiflora were studied by scanning electron microscopy. The trichomes are mainly present on abaxial leaf surface in most species, but rarely they appear on adaxial surface. Five trichome types are identified as simple uniseriate, bulbous, solitary, fasciculate and stellate. The stomata of all studied species are of the anomocytic type, raised on the epidermis. The stomata rim may or may not be covered with epicuticular. The epicuticular waxes are mostly of the crystalloid type but smooth layer wax is observed in Q. robur subsp. pedunculiflora. Statistical analysis revealed foliar micromorphological features as been diagnostic characters in Quercus
Comparison of flora, life forms and chorology in the two untouched and degraded sites in Beech forests (Case study: Shafaroud forests.Gilan,Iran)
Beitollah Amanzadeh,Mohammad Reza Pourmajidian,Ahmad Rahmani,Aiuob Moradi
International Journal of Forest, Soil and Erosion , 2013,
Abstract: : In order to study on environmental changes effects on understory vegetation, two untouched and degraded sites were evaluated in Shafaroud forests. Three sampling plots (one hectare in each site) were selected and each plot divided to four sub-plots (10*10m).In each Sub-plot plant samples were collected and identified using different flora references. Results showed that a total 45 species were known from untouched area that belong to 28 families and 39 genera. 32(71%) dicotyledones ,8 (18%) monocotyledones and 5 (11%) pterydophyta were identified. Lamiacea with four species was the highest number species.17 families have only one species. Flora of degraded site includes 74 species (60 (80%) dictyledones, 9 (12%) monocotyledones and 5 (8%) pterdophyta) that belong to 32 families and 62 genera. Asteraceae with 9 species are the most abundant in this area. Also 7 species of Lamiaceae family were identified in degraded area. hemichryptophytes are the most frequent life forms in the both areas. From the view of geographical distribution, plants of untouched area included 69% species belonging to Euro-Sibrean and only 2.5% species belonging to Cosmopolitan while in degraded area 51% and 3.5% species belaged to Euro-Sibrean and Cosmopolitan, respectively. Key Words: degraded ecosystems, life forms , chorology Caspian forests
Steady-State Thermal-Hydraulic Analysis of TRIGA Research Reactor  [PDF]
Mohammad Mizanur Rahman, Mohammad Abdur R. Akond, Mohammad Khairul Basher, Md. Quamrul Huda
World Journal of Nuclear Science and Technology (WJNST) , 2014, DOI: 10.4236/wjnst.2014.42013
Abstract:

The COOLOD-N2 and PARET computer codes were used for a steady-state thermal hydraulic and safety analysis of the 3 MW TRIGA Mark-II research reactor located at Atomic Energy Research Establishment (AERE), Savar, Dhaka, Bangladesh. The objective of the present study is to ensure that all important safety related thermal hydraulic parameters uphold margins far below the safety limits by steady-state calculations at full power. We, therefore, have calculated the hot channel fuel centreline temperature, fuel surface temperature, cladding surface temperature, the departure from nucleate boiling (DNB) heat flux and DNB ratio, axial fuel centreline temperature and compared. The comparison indicates that the calculated values are in satisfactory agreement between the codes. The data obtained in this investigation are largely far to compromise safety of the reactor. The results can also be used to upgrade the current core configuration of the TRIGA reactor.

A predictive kinetic model for inhibitory effect of nitrite on myeloperoxidase catalytic activity towards oxidation of chloride  [PDF]
Yahya R. Tahboub, Mohammad M. Fares
Journal of Biophysical Chemistry (JBPC) , 2011, DOI: 10.4236/jbpc.2011.23024
Abstract: Myeloperoxidase (MPO) is a neutrophil enzyme that employs hydrogen peroxide (H2O2) to catalyze the oxidation of chloride (Cl–) to hypochlorous acid (HOCl). Accepted mechanism is based on rapid reaction of native MPO with H2O2to produce Compound I (MPO-I) which oxidizes Cl– through a 2e– transition generating MPO and HOCl. MPO-I also reacts with H2O2 to generate Compound II (MPO-II) which is inactive in 2e oxidation of Cl–. Nitrite ( NO2-) inhibits the 2e oxidation of Cl– by reaction with MPO-I through 1e transition generating MPO-II and nitrite radical. H2O2 consumption during steady- state catalysis was monitored amperometrically by a carbon fiber based H2O2-biosensor at 25oC. Results demonstrated that in absence of NO2- reactions were monophasic and rapid (complete H2O2 consumption occurs in < 10 s). As concentration of NO2- increases, reactions change to biphasic (rapid step followed by a slow step) and both steps have been inhibited by NO2- . A predictive kinetic model describing the inhibittory effect of NO2- was developed and applied to experimental results The model is based on the assumption that MPO–I cannot be detected during steady-state catalysis. Calculated rate constants are in agreement with those obtained from pre-steady state kinetic methods.
Application of the Alpha Shape Method to Visualize and Analyze Surgical Motion  [PDF]
Mohammad R. Maddah, Caroline G. L. Cao
Surgical Science (SS) , 2017, DOI: 10.4236/ss.2017.811052
Abstract: Simulators play an important role in training surgery residents to perform laparoscopy surgery. Some of these simulators have the capability to track tool motion to assess performance. However, most have not utilized the data to analyze trainee performance in a meaningful way. The alpha shape method can be used to construct a geometric surface based on motion data to enable visualization of the performance, while the surface derivative (surface/time to completion)—efficiency—can be used as a metric to evaluate complex surgical performance. The utility of the alpha shape method was demonstrated in a pick-and-place task, where the motion path of laparoscopic graspers was recorded by a position sensor, miniBIRD 500？. An alpha shape method was used to measure the surface area of the 3D points in space occupied by the tool tips during task performance. Results show that the surface derivative measure alone may be able to model the speed-accuracy tradeoff function, thereby simplifying the analysis and evaluation of complex motion in surgical performance.
Optimal Path Planning for a Remote Sensing Unmanned Ground Vehicle in a Hazardous Indoor Environment  [PDF]
Mohammad R. Alenezi, Abdullah M. Almeshal
Intelligent Control and Automation (ICA) , 2018, DOI: 10.4236/ica.2018.94011
Abstract: Urban search and rescue robots are playing an increasingly important role during disasters and with their ability to search within hazardous and dangerous environments to assist the first respond teams. Surveying and remote sensing the hazardous areas are two of the urgent needs of the rescue team to identify the risks before the intervention of the emergency teams. With such time-critical missions, the path planning and autonomous navigation of the robot is one of the primary concerns due to the need of fast and feasible path that is comprehensive enough to assess the associated risks. This paper presents a path planning method for navigating an unmanned ground vehicle within in an indoor hazardous area with minimum priori information. The algorithm can be generalized to any given map and is based on probabilistic roadmap path planning method with spiral dynamics optimization algorithm to obtain the optimal navigating path. Simulations of the algorithm are presented in this paper, and the results promising results are illustrated using Matlab and Simulink simulation environments.
Effect of socio-demographic status on dental caries in pupils by using a multilevel hurdle model  [PDF]
Yunes Jahani, Mohammad R. Eshraghian, Abbas R. Foroushani, Keramat Nourijelyani, Kazem Mohammad, Arash Shahravan, Mahin Alam
Health (Health) , 2013, DOI: 10.4236/health.2013.57150
Abstract:

Introduction: Dental caries is the most prevalent chronic disease among schoolchildren. We aimed to investigate the association between dental caries index and socio-demographic status in schoolchildren by using a multilevel hurdle model. Materials and Methods: A cross-sectional epidemiological study was carried out on 906 primary school pupils in Kerman, Iran in 2012. The subjects were selected through a stratified cluster random sampling. At first, the whole target area was stratified according to two geographic areas, the north and south area. Then each area was stratified according to gender. In the next step, several schools were considered as clusters, which were selected randomly in each geographic area and gender strata. All the schoolchildren in these schools were included in this study as samples. Twelve-year-old pupils were examined for dental caries. The dependent variable in this study was the dmft/DMFT index. Eight variables, including socio-demographic information, were collected. Multilevel negative binomial hurdle model was employed for data analysis. Results: The prevalence of caries-free pupils was 30.1% and the mean dmft/DMFT was 3.6 ± 2.2. Negative binomial part of the adjusted model showed that the dmft/DMFT adjusted rate for females was 1.36 (95% CI: 1.10-1.79) times higher than males. Also, the dmft/DMFT adjusted rate for overweight pupils was 0.86 (95% CI: 0.74-0.98) times lower than those with normal weight. Logistic part of the adjusted model showed that the posibility of caries-free state in overweight pupils was 1.95 (95% CI: 1.22-3.11) times higher than those with normal weight. In addition, pupils whose fathers and mothers were workers and housewives, respectively, and those with a high maternal age were at a greater risk for caries experience than others (p < 0.05). Conclusion: BMI, gender, parent’s job and mother’s age at delivery were factors effecting on dental caries in schoolchildren. These pupils need more attention to dental care.

A G-KKM type theorem and its applications to minimax inequalities on G-convex spaces
Mohammad S. R. Chowdhury
International Journal of Stochastic Analysis , 1998, DOI: 10.1155/s1048953398000409
Abstract: A G-KKM type theorem is obtained on G-convex spaces. As application, a generalization of Ky Fan's minimax inequality to non-compact sets on G-convex spaces is first obtained. As special cases of this minimax inequality, some new minimax inequalites are obtained. Four fixed point theorems and four equivalent formulations of the second minimax inequality are also obtained.
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