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Risk Factors for Early Discontinuation of Breastfeeding in Iranian Mothers

Open Journal of Obstetrics and Gynecology 2016年第10期6卷 606-614页

作者： fatemeh ghotbi Ali Naseh Eznollah Azargashb Shahrbano Hajimola Ahmad Naraghi Azadeh Akbari Sene Infertility and Reproductive Health Research Center (IRHRC) Shahid Beheshti University of Medical Sciences Tehran Iran Neonatal Intensive Care Unit Taleghani Hospital Shahid Beheshti University of Medical Sciences Tehran Iran Department of Social Medicine Shahid Beheshti University of Medical Sciences Tehran Iran Department of Obstetrics and Gynecology Taleghani Hospital Shahid Beheshti University of Medical Sciences Tehran Iran OBGYN/IVF Fellowship Iran University of Medical Sciences Shahid Akbar-Abadi Hospital IVF Center Tehran Iran

Objective: The present study was conducted to evaluate the risk factors that reduce the rate of breastfeeding among Iranian women in the first six months after delivery. Materials and Methods: This cross sectional study was performed on 542 mothers with infants less than six months old who came to Taleghani Hospital, Tehran, Iran, for vaccination follow up, from 2012 to 2014. Trained examiners filled a predesigned questionnaire including information about breastfeeding and factors that may affect the mode of infant feeding. The results were analyzed using SPSS software. Results: Out of 542 breastfeeding infants 53.2% were female;the average birth weight was 3217 ± 40 gr and 57.7% were first born. The age of mothers was from 17 to 43 years with the average of 27.7 ± 4.9. Among mothers 58.1% had a high school diploma or less education and 41.9% had higher education. The rate of cesarean section was 62.2%. The rate of breastfeeding showed a reducing trend from the first month after birth to the sixth month: 91.7% of mothers reported breastfeeding in the first month which was reduced to 70.1% in the sixth month. Multivariate analysis using logistic regression analysis showed the risk factors reducing the rate of breastfeeding as follow: use of pacifier (P 0.000, OR = 3.695, CI95% = 2.460 - 5.553), cesarean section delivery (p 0.000, OR = 2.717, CI95% = 1.690 - 4.369), lack of breastfeeding training (P = 0.004, OR = 2.347, CI95% = 1.354 - 4.063), and mothers’ higher education (P = 0.029, OR = 1.614, CI95% = 1.014 - 2.569). Conclusion: Use of pacifiers, cesarean section, lack of breastfeeding training, and mothers’ higher education were the risk factors for reduced breastfeeding among Iranian mothers.

关键词： Infant Breastfeeding Pacifier Risk Factor Cesarean Section

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Conversion of CO into CO_(2) by high active and stable PdNi nanoparticles supported on a metal-organic framework

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Frontiers of Chemical Science and Engineering 2022年第7期16卷 1139-1148页

作者： Fateme Abbasi Javad Karimi-Sabet Zeinab Abbasi Cyrus ghotbi Department of Petroleum and Chemical Engineering Sharif University of TechnologyTehranIran Nuclear Fuel Cycle Research School Nuclear Science and Technology Research InstituteTehranIran

The solubility of Pd(NO_(3))_(2) in water is moderate whereas it is completely soluble in diluted HNO_(3) solution. Pd/MIL-101(Cr) and Pd/MIL-101-NH_(2)(Cr) were synthesized by aqueous solution of Pd(NO_(3))_(2) and Pd(NO_(3))_(2) solution in dilute HNO_(3) and used for CO oxidation reaction. The catalysts synthesized with Pd(NO_(3))_(2) solution in dilute HNO_(3) showed lower activity. The aqueous solution of Pd(NO_(3))_(2) was used for synthesis of mono-metal Ni, Pd and bimetallic PdNi nanoparticles with various molar ratios supported on MOF. Pd_(70)Ni_(30)/MIL-101(Cr) catalyst showed higher activity than monometallic counterparts and Pd+ Ni physical mixture due to the strong synergistic effect of PdNi nanoparticles, high distribution of PdNi nanoparticles, and lower dissociation and desorption barriers. Comparison of the catalysts synthesized by MIL-101(Cr) and MIL-101-NH_(2)(Cr) as the supports of metals showed that Pd/MIL-101-NH_(2)(Cr) outperforms Pd/MIL-101-(Cr) because of the higher electron density of Pd resulting from the electron donor ability of the NH_(2) functional group. However, the same activities were observed for Pd_(70)Ni_(30)/MIL-101(Cr) and Pd_(70)Ni_(30)/MIL-101-NH_(2)(Cr), which is due to a less uniform distribution of Pd nanoparticles in Pd_(70)Ni_(30)/MIL-101-NH_(2)(Cr) originated from amorphization of MIL-101-NH_(2)(Cr) structure during the reduction process. In contrast, Pd_(70)Ni_(30)/MIL-101(Cr) revealed the stable structure and activity during reduction and CO oxidation for a long time.

关键词： CO oxidation heterogeneous catalysis metal-organic framework NH_(2)functional group PdNi

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Performance-based seismic assessment of a large diameter extended pile shaft in a cohesionless soil

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Earthquake Engineering and Engineering Vibration 2015年第1期14卷 177-188页

作者： Abdoul R.ghotbi Civil & Environmental Engineering Department University of California

The seismic behavior of a large diameter extended pile shaft founded on a dense sandy site is investigated in this paper. First, a deterministic analysis is conducted including both nonlinear dynamic analysis （NDA） and pushover analysis to gain insights into the behavior of the pile and make sure an appropriate modeling technique is utilized. Then a probabilistic analysis is performed using the results of NDA for various demands. To this end a set of 40 pulse-like ground motions are picked and subsequently 40 nonlinear dynamic and pushover analyses are performed. The data obtained from NDA are used to generate probabilistic seismic demand model （PSDM） plots and consequently the median line and dispersion for each plot are computed. The NDA and pushover data are also plotted against each other to find out to what extent they are correlated. These operations are done for various engineering demand parameters （EDPs）. A sensitivity analysis is done to pick the most appropriate intensity measure （IM） which would cause a minimum dispersion in PSDM plots out of 7 different IMs. Peak ground acceleration （PGA） is found to be the most appropriate IM. Pushover coefficient equations as a function of PGA are proposed which can be applied to the pushover analysis data to yield a better outcome with respect to the NDA. At the end, the pacific earthquake engineering research （PEER） center methodology is utilized to generate the fragility curves using the properties obtained from PSDM plots and considering various states of damage ranging from minor to severe. The extended pile shaft shows more vulnerability with a higher probability with respect to minor damage compared to severe damage.

关键词： extended pile shaft NDA pushover IMs PSDM fragility functions

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Nickel doped zinc oxide nanoparticles produced by hydrothermal decomposition of nickel-doped zinc hydroxide nitrate

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Particuology 2012年第4期10卷 492-496页

作者： Mohammad Yeganeh ghotbi Nanomaterials and Nanotechnology Program Ceramic Engineering DepartmentFaculty of EngineeringMalayer UniversityMalayerIran

Zinc hydroxide nitrate, an anionic exchanger layered material, undoped as well as doped with 2-10% nickel, was synthesized by using a pH-controlled precipitation method. The layered materials were then used to produce the undoped and nickel-doped zinc oxides by hydrothermal-treatment. X-ray diffraction, Fourier transform infrared spectroscopy and scanning electron microscopy confirmed the formation of pure phase undoped and nickel-doped layered materials, as well as the products of the hydrothermal- treated materials, nanostructured zinc oxides. Optical studies of the nanostructured zinc oxides showed a decrease in band gap with increasing content of the doping agent, nicke~.

关键词： NanostructureNickel doped zinc oxideChemical synthesisBand gap

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Performance-based seismic assessment of skewed bridges with and without considering soil-foundation interaction effects for various site classes

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Earthquake Engineering and Engineering Vibration 2014年第3期13卷 357-373页

作者： Abdoul R.ghotbi Civil & Environmental Engineering Department University of California

The seismic behavior of skewed bridges has not been well studied compared to straight bridges. Skewed bridges have shown extensive damage, especially due to deck rotation, shear keys failure, abutment unseating and column- bent drift. This research, therefore, aims to study the behavior of skewed and straight highway overpass bridges both with and without taking into account the effects of Soil-Structure Interaction （SSI） due to near-fault ground motions. Due to several sources of uncertainty associated with the ground motions, soil and structure, a probabilistic approach is needed. Thus, a probabilistic methodology similar to the one developed by the Pacific Earthquake Engineering Research Center （PEER） has been utilized to assess the probability of damage due to various levels of shaking using appropriate intensity measures with minimum dispersions. The probabilistic analyses were performed for various bridge configurations and site conditions, including sand ranging from loose to dense and clay ranging from soft to stiff, in order to evaluate the effects. The results proved a considerable susceptibility of skewed bridges to deck rotation and shear keys displacement. It was also found that SSI had a decreasing effect on the damage probability for various demands compared to the fixed-base model without including SSI. However, deck rotation for all types of the soil and also abutment unseating for very loose sand and soft clay showed an increase in damage probability compared to the fixed-base model. The damage probability for various demands has also been found to decrease with an increase of soil strength for both sandy and clayey sites. With respect to the variations in the skew angle, an increase in skew angle has had an increasing effect on the amplitude of the seismic response for various demands. Deck rotation has been very sensitive to the increase in the skew angle; therefore, as the skew angle increased, the deck rotation responded accordingly. Furthermor

关键词： skewed bridges SSI demand model probabilistic assessment damage probability

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Application of numerical modeling and genetic programming to estimate rock mass modulus of deformation

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International Journal of Mining Science and Technology 2013年第5期23卷 733-737页

作者： Ebrahim ghotbi Ravandi Reza Rahmannejad Amir Ehsan Feili Monfared Esmaeil ghotbi Ravandi Mineral Industries Research Center Shahid Bahonar University of Kerman Mining Engineering Department Shahid Bahonar University of Kerman Chemical Engineering Department Shahid Bahonar University of Kerman Civil Engineering Department Shahid Bahonar University of Kerman

Estimation of the rock mass modulus of deformation(Em)is one of the most important design parameters in designing many structures in and on *** parameter can be obtained by in situ tests,empirical relations between deformation modulus and rock mass classifcation,and estimating from laboratory tests *** this paper,a back analysis calculation is performed to present an equation for estimation of the rock mass modulus of deformation using genetic programming(GP)and numerical modeling.A database of 40,960 datasets,including vertical stress(rz),horizontal to vertical stresses ratio(k),Poisson’s ratio(m),radius of circular tunnel(r)and wall displacement of circular tunnel on the horizontal diameter(d)for input parameters and modulus of deformation for output,was *** selected parameters are easy to determine and rock mass modulus of deformation can be obtained from instrumentation data of any size circular *** resulting RMSE of 0.86 and correlation coeffcient of97%of the proposed equation demonstrated the capability of the computer program(CP)generated by GP.

关键词： Modulus of deformation(Em) Displacement Numerical modeling Genetic programming(GP) Back analysis

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Weighing and Prioritizing Noise Control Methods Using the Delphi Technique and the Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) in an Iranian Tire Manufacturing Factory

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Sound & Vibration 2020年第3期54卷 201-213页

作者： Mohammad Reza ghotbi-Ravandi Davoud Hassanvand Sajad Zare Milad Beytollahi Associate Professor Department of Occupational HealthSchool of Public HealthKerman University of Medical Sciences and Health ServicesKermanIran Master of Occupational Health Student Research CommitteeSchool of Public HealthKerman University of Medical Sciences and Health ServicesKermanIran Assistant Professor Department of Occupational HealthSchool of Public HealthKerman University of Medical Sciences and Health ServicesKermanIran Department of Industrial Engineering Faculty of EngineeringShahid Bahonar University of KermanKermanIran

Undoubtedly,noise has become a major hazardous issue in today’s industrial world,with a lot of people suffering from exposure to excessive noise in their work *** study was conducted to weigh and prioritize noise control methods in an Iranian tire manufacturing complex in *** Delphi method and the Technique for Order Preference by Similarity and an Ideal Solution(TOPSIS)were utilized for this *** cross-sectional,descriptive study was conducted in the baking hall of an Iranian tire manufacturing factory in *** weigh and prioritize noise control methods,Analytic Hierarchy Process(AHP)and TOPSIS were *** total,4 criteria and 8 alternatives were *** AHP and TOPSIS questionnaire was then designed to prioritize noise control methods in the light of the objectives,criteria,and ***,the collected data were fed into Expert Choise.V.11 and Excel and data analysis was carried out using *** results of data analysis indicated that the inconsistency rate in all the cases was smaller than 10%,hence the consistency of the responses was *** to the TOPSIS results and experts’opinions about the criteria,implementation and maintenance cost(with a weight of 0.481)and method effectiveness and efficiency(with a weight of 0.046)had the highest and lowest priority *** on the weights TOPSIS,the appropriate methods for controlling noise in tire manufacturing are designing and manufacturing silencer,requiring people in charge to quickly fix the leaks and change baking press washers on time.

关键词： Ranking noise control methods TOPSIS delphi technique

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Theoretical and Experimental Study on the Adsorption and Desorption of Methane by Granular Activated Carbon at 25℃

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Journal of Natural Gas Chemistry 2007年第4期16卷 415-422页

作者： E.Salehi V.Taghikhani C.ghotbi E.Nemati Lay A.Shojaei Department of Chemical and Petroleum Engineering Sharif University of Technology TehranIran

A theoretical and experimental study was conducted to accurately determine the amount of adsorption and desorption of methane by various Granular Activated Carbon （GAC） under different physical conditions. To carry out the experiments, the volumetric method was used up to 500 psia at constant temperature of 25℃. In these experiments, adsorption as well as desorption capacities of four different GAC in the adsorption of methane, the major constituent of natural gas, at various equilibrium pressures and a constant temperature were studied. Also, various adsorption isotherm models were used to model the experimental data collected from the experiments. The accuracy of the results obtained from the adsorption isotherm models was compared and the values for the regressed parameters were reported. The results shows that the physical characteristics of activated carbons such as BET surface area, micropore volume, packing density, and pore size distribution play an important role in the amount of methane to be adsorbed and desorbed.

关键词： methane adsorption volumetric method activated carbon two-term TVFM isotherm

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Using Audiometric Data to Weigh and Prioritize Factors that Affect Workers’ Hearing Loss through Support Vector Machine (SVM) Algorithm

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Sound & Vibration 2020年第2期54卷 99-112页

作者： Hossein ElahiShirvan MohammadReza ghotbi-Ravandi Sajad Zare Mostafa Ghazizadeh Ahsaee Student Research Committee Kerman University of Medical SciencesKermanIran Associate Professor Department of Occupational HealthSchool of Public HealthKerman University of Medical SciencesKermanIran Assistant Professor Department of Occupational HealthSchool of Public HealthKerman University of Medical SciencesKermanIran Assistant Professor Department of Computer EngineeringShahid Bahonar UniversityKermanIran

Workers’exposure to excessive noise is a big universal work-related *** of the major consequences of exposure to noise is permanent or transient hearing *** current study sought to utilize audiometric data to weigh and prioritize the factors affecting workers’hearing loss based using the Support Vector Machine(SVM)*** cross sectional-descriptive study was conducted in 2017 in a mining industry in southeast *** participating workers(n=150)were divided into three groups of 50 based on the sound pressure level to which they were exposed(two experimental groups and one control group).Audiometric tests were carried out for all members of each *** study generally entailed the following steps:(1)selecting predicting variables to weigh and prioritize factors affecting hearing loss;(2)conducting audiometric tests and assessing permanent hearing loss in each ear and then evaluating total hearing loss;(3)categorizing different types of hearing loss;(4)weighing and prioritizing factors that affect hearing loss based on the SVM algorithm;and(5)assessing the error rate and accuracy of the *** collected data were fed into SPSS 18,followed by conducting linear regression and paired samples *** was revealed that,in the first model(SPL85 dBA),the frequency of 4 KHz had the highest impact(with a weight of 22%),while the frequency of 250 Hz had the smallest influence(with a weight of 3%).The accuracy of this model was 100%*** the fourth model,the frequency of 4 KHz had the greatest effect(with a weight of 24%),while the

关键词： Noise modeling hearing loss data mining support vector machine algorithm

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Experimental and Theoretical Study of the Effect of Moisture on Methane Adsorption and Desorption by Activated Carbon at 273.5 K

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Journal of Natural Gas Chemistry 2007年第1期16卷 22-30页

作者： S.Farzad V.Taghikhani C.ghotbi B.Aminshahidi E.Nemati Lay Department of Chemical and Petroleum Engineering Sharif University of TechnologyTehranIran

Adsorption and desorption of methane by activated carbon （AC） at constant temperature and at various pressures were investigated. The effect of moisture was also studied. A volumetric method was used, up to 40 bar, at a temperature of 273.5 K. Results of a dry AC sample were compared with those obtained from a moist sample and two different ACs with different physical and surface properties were used. As expected, the results showed that the existence of moisture, trapped in the AC pores, could lead to a decrease in the amount of methane adsorbed and a decrease in the amount of methane delivered during desorption. To model the experimental results, a large variety of adsorption isotherms were used. The regressed parameters for the adsorption isotherms were obtained using the experimental data generated in the present study. The accuracy of the results obtained from the different adsorption isotherms was favorably compared.

关键词： activated carbon adsorption adsorption properties thermodynamic analysis

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