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      • SCOPUSKCI등재

        Optimization of Extended UNIQUAC Parameter for Activity Coefficients of Ions of an Electrolyte System using Genetic Algorithms

        Hashemi, Seyed Hossein,Dehghani, Seyed Ali Mousavi,Khodadadi, Abdolhamid,Dinmohammad, Mahmood,Hosseini, Seyed Mohsen,Hashemi, Seyed Abdolrasoul The Korean Institute of Chemical Engineers 2017 Korean Chemical Engineering Research(HWAHAK KONGHA Vol.55 No.5

        In the present research, in order to predict activity coefficient of inorganic ions in electrolyte solution of a petroleum system, we studied 13 components in the electrolyte solution, including $H_2O$, $CO_2$ (aq), $H^+$, $Na^+$, $Ba^{2+}$, $Ca^{2+}$, $Sr^{2+}$, $Mg^{2+}$, $SO_4$, $CO_3$, $OH^-$, $Cl^-$, and $HCO_3$. To predict the activity coefficient of the components of the petroleum system (a solid/liquid equilibrium system), activity coefficient model of Extended UNIQUAC was studied, along with its adjustable parameters optimized based on a genetic algorithm. The total calculated error associated with optimizing the adjustable parameters of Extended UNIQUAC model considering the 13 components under study at three temperature levels (298.15, 323.15, and 373.15 K) using the genetic algorithm is found to be 0.07.

      • Expression of Neuronal Markers, NFP and GFAP, in Malignant Astrocytoma

        Hashemi, Forough,Naderian, Majid,Kadivar, Maryam,Nilipour, Yalda,Gheytanchi, Elmira Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.15

        Background: Immunohistochemical markers are considered as important factors in diagnosis of malignant astrocytomas. The aim of the current study was to investigate the frequency of the immunohistochemical markers neurofilament protein (NFP) and glial fibrillary acidic protein (GFAP) in malignant astrocytoma tumors in Firoozgar and Rasool-Akram hospitals from 2005 to 2010. Materials and Methods: In this cross-sectional study, immunohistochemical analysis of NFP and GFAP was performed on 79 tissue samples of patients with the diagnosis of anaplastic and glioblastoma multiform (GBM) astrocytomas. Results: The obtained results demonstrated that all patients were positive for GFAP and only 3.8% were positive for NFP. There was no significant association between these markers and clinical, demographic, and prognostic features of patients (p>0.05). Conclusions: NFP was expressed only in GBMs and not in anaplastic astrocytomas. It would be crucial to confirm the present findings in a larger number of tumors, especially in high grade gliomas.

      • Concurrent Chemoradiation with Weekly Gemcitabine and Cisplatin for Locally Advanced Cervical Cancer

        Hashemi, Farnaz Amouzegar,Akbari, Ehsan Hamed,Kalaghchi, Bita,Esmati, Ebrahim Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.9

        Background: For more than 80 years, the standard treatment of locally advanced cervical cancer was radiotherapy. However, based on several phase III randomized clinical trials in the past decade, concurrent cisplatin-based chemoradiotherapy is the current standard for this disease. Gemcitabine has potent radiosensitizing properties in preclinical and clinical trials, so it can be utilized simultanously with radiation. Materials and Methods: Thirty women with untreated invasive squamous cell carcinoma of the cervix of stage IIB to stage IVA were enrolled in the study in the Radiation Oncology Department of Imam Khomeini Hospital in Tehran from September 2009 to September 2010. Sixty $mg/m^2$ gemcitabine followed by $35mg/m^2$ cisplatin were concurrently administered with radiotherapy to the whole pelvic region on day one of each treatment week for five weeks. One and three months after treatment, patients underwent a complete physical examination and MRI to determine the response to treatment. Results: The mean age of patients was $58.1{\pm}11.8$ (29-78) years. After 3 months of treatment, 73.3%had complete and 26.7% demonstrated partial response to treatment. Grade 3 anemia was seen in 10%, grade 3 thrombocytopenia in 3.3% and grade 3 leukopenia in 10% of the patients. Conclusions: According to the positive results of this study in stage IIB, further phase II and III clinical trials are suggested to evaluate the role of chemoradiation using Gemcitabine for advanced cervical cancers.

      • SCOPUSKCI등재

        Molecularly Imprinted Polymers for Solid-Phase Extraction of Sarcosine as Prostate Cancer Biomarker from Human Urine

        Hashemi-Moghaddam, Hamid,Rahimian, Majid,Niromand, Bahman Korean Chemical Society 2013 Bulletin of the Korean Chemical Society Vol.34 No.8

        A highly selective molecularly imprinted polymer (MIP) for sarcosine, a cancer marker, was prepared and its use as solid-phase extraction (SPE) sorbent material was demonstrated. The MIP was prepared by a very simple procedure using methacrylic acid as functional monomer and a mixture acetonitrile/water (4/1, v/v) as porogen, overcoming in this way the problems usually related to the imprinting of biological polar compounds. The MIP was tested in batch experiments in order to evaluate its binding properties and then used as SPE sorbent for the selective clean-up and pre-concentration of sarcosine. The extraction protocol was successfully applied to the direct extraction of sarcosine from spiked human urine indicating that the MIP allowed sarcosine to be pre-concentrated while simultaneously interfering compounds were removed from the matrix.

      • SCIESCOPUSKCI등재

        SKEW POWER SERIES EXTENSIONS OF α-RIGID P.P.-RINGS

        Hashemi, Ebrahim,Moussavi, Ahmad Korean Mathematical Society 2004 대한수학회보 Vol.41 No.4

        We investigate skew power series of $\alpha$-rigid p.p.-rings, where $\alpha$ is an endomorphism of a ring R which is not assumed to be surjective. For an $\alpha$-rigid ring R, R[[${\chi};{\alpha}$]] is right p.p., if and only if R[[${\chi},{\chi}^{-1};{\alpha}$]] is right p.p., if and only if R is right p.p. and any countable family of idempotents in R has a join in I(R).

      • SCOPUSKCI등재

        ON RADICALLY-SYMMETRIC IDEALS

        Hashemi, Ebrahim Korean Mathematical Society 2011 대한수학회논문집 Vol.26 No.3

        A ring R is called symmetric, if abc = 0 implies acb = 0 for a, b, c ${\in}$ R. An ideal I of a ring R is called symmetric (resp. radically-symmetric) if R=I (resp. R/$\sqrt{I}$) is a symmetric ring. We first show that symmetric ideals and ideals which have the insertion of factors property are radically-symmetric. We next show that if R is a semicommutative ring, then $T_n$(R) and R[x]=($x^n$) are radically-symmetric, where ($x^n$) is the ideal of R[x] generated by $x^n$. Also we give some examples of radically-symmetric ideals which are not symmetric. Connections between symmetric ideals of R and related ideals of some ring extensions are also shown. In particular we show that if R is a symmetric (or semicommutative) (${\alpha}$, ${\delta}$)-compatible ring, then R[x; ${\alpha}$, ${\delta}$] is a radically-symmetric ring. As a corollary we obtain a generalization of [13].

      • KCI등재

        Effect of 38% carbamide peroxide on the microleakage of silorane-based versus methacrylate-based composite restorations

        Hashemi Kamangar, Sedighe Sadat,Ghavam, Maryam,Mahinfar, Nazanin,Pourhashemi, Seyed Jalal The Korean Academy of Conservative Dentistry 2014 Restorative Dentistry & Endodontics Vol.39 No.3

        Objectives: This study aimed to assess the effect of 38% carbamide peroxide on the microleakage of class V cavities restored with either a silorane-based composite or two methacrylate-based composites. Materials and Methods: A total of 96 class V cavities were prepared on the buccal surface of extracted human teeth with both enamel and dentin margins and were randomly assigned into three groups of Filtek P90 (3M-ESPE) + P90 system adhesive (3M-ESPE)(group A), Filtek Z250 (3M-ESPE) + Adper Prompt L-Pop (3M-ESPE)(group B) and Filtek Z350XT (3M-ESPE) + Adper Prompt L-Pop (group C). Half of the teeth were randomly underwent bleaching (38% carbamide peroxide, Day White, Discus Dental, applying for 15 min, twice a day for 14 day) while the remaining half (control) were not bleached. Dye penetration was measured following immersion in basic fuchsine. Data were statistically analyzed using Kruskal-Wallis and Mann-Whitney U tests at a level of 0.05. Results: No significant differences were found between composites in the control groups in enamel (p = 0.171) or dentin (p = 0.094) margins. After bleaching, microleakage of Z250 (in enamel [p = 0.867] or dentin [p = 0.590] margins) and Z350 (in enamel [p = 0.445] or dentin [p = 0.591]margins) did not change significantly, but the microleakage of P90 significantly increased in both enamel (p = 0.042) and dentin (p = 0.002) margins. Conclusions: No significant differences were noted between the bleached and control subgroups of two methacrylate-based composites in enamel or dentin margins. Microleakage of silorane-based composite significantly increased after bleaching.

      • SCIESCOPUSKCI등재

        SOME EXAMPLES OF QUASI-ARMENDARIZ RINGS

        Hashemi, Ebrahim Korean Mathematical Society 2007 대한수학회보 Vol.44 No.3

        In [12], McCoy proved that if R is a commutative ring, then whenever g(x) is a zero-divisor in R[x], there exists a nonzero c $\in$ R such that cg(x) = 0. In this paper, first we extend this result to monoid rings. Then for a monoid M, we give some examples of M-quasi-Armendariz rings which are a generalization of quasi-Armendariz rings. Every reduced ring is M-quasi-Armendariz for any unique product monoid M and any strictly totally ordered monoid $(M,\;{\leq})$. Also $T_4(R)$ is M-quasi-Armendariz when R is reduced and M-Armendariz.

      • SCIESCOPUSKCI등재

        ON SOME TYPE ELEMENTS OF ZERO-SYMMETRIC NEAR-RING OF POLYNOMIALS

        Hashemi, Ebrahim,Shokuhifar, Fatemeh Korean Mathematical Society 2019 대한수학회지 Vol.56 No.1

        Let R be a commutative ring with unity. In this paper, we characterize the unit elements, the regular elements, the ${\pi}$-regular elements and the clean elements of zero-symmetric near-ring of polynomials $R_0[x]$, when $nil(R)^2=0$. Moreover, it is shown that the set of ${\pi}$-regular elements of $R_0[x]$ forms a semigroup. These results are somewhat surprising since, in contrast to the polynomial ring case, the near-ring of polynomials has substitution for its "multiplication" operation.

      • KCI등재

        Investigation Plant Species Diversity and Physiographical Factors in Mountain Forest in North of Iran

        Hashemi, Seyed Armin Institute of Forest Science 2010 Journal of Forest Science Vol.26 No.1

        Species diversity is one of the most important specifications of biological societies. Diversity of organisms, measurement of variety and examination of those hypotheses that are about reasons of diversity are such as affairs that have been desired by the ecologists for a long time. In this research, diversity of plant species in forest region, numbers of 60 sample plots in 256.00 square meters have been considered in random - systematic inventory was considered. In each sample plot, four micro-plots in 2.25 square meters in order to study on herbal cover, were executed that totally 240 micro-plots were considered. At each plot six diversity indices in relation to physiographic factors (slope, geographical aspect and altitude from the sea level) were studied. The results indicate that species diversity is more in the northern direction and also species diversity in slops less than 30% has the most amounts. Factor of altitude from the sea level did not have meaningful relation with species diversity. Through study on correlation of the numbers of species in sample plots with indices and also process and role of indices in different processors of analysis, Simpson's reciprocal index was suggested as suitable index in this type of studies.

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