Surgical management of a failed internal root resorption treatment: a histological and clinical

Asgary, Saeed,Eghbal, Mohammad Jafar,Mehrdad, Leili,Kheirieh, Sanam,Nosrat, Ali The Korean Academy of Conservative Dentistry 2014 Restorative Dentistry & Endodontics Vol.39 No.2

This article presents the successful surgical management of a failed mineral trioxide aggregate (MTA) orthograde obturation of a tooth with a history of impact trauma and perforated internal root resorption. A symptomatic maxillary lateral incisor with a history of perforation due to internal root resorption and nonsurgical repair using MTA was referred. Unintentional overfill of the defect with MTA had occurred 4 yr before the initial visit. The excess MTA had since disappeared, and a radiolucent lesion adjacent to the perforation site was evident radiographically. Surgical endodontic retreatment was performed using calcium enriched mixture (CEM) cement as a repair material. Histological examination of the lesion revealed granulation tissue with chronic inflammation, and small fragments of MTA encapsulated within fibroconnective tissue. At the one and two year follow up exams, all signs and symptoms of disease had resolved and the tooth was functional. Complete radiographic healing of the lesion was observed two years after the initial visit. This case report illustrates how the selection of an appropriate approach to treatment of a perforation can affect the long term prognosis of a tooth. In addition, extrusion of MTA into a periradicular lesion should be avoided.

Design of ionic liquid 1,3-disulfonic acid imidazolium hydrogen sulfate as a dual-catalyst for the one-pot multi-component synthesis of 1,2,4,5-tetrasubstituted imidazoles

Mohammad Ali Zolfigol,Ardeshir Khazaei,Ahmad Reza Moosavi-Zare,Abdolkarim Zare,Zhila Asgari,Vahid Khakyzadeh,Alireza Hasaninejad 한국공업화학회 2013 Journal of Industrial and Engineering Chemistry Vol.19 No.3

Novel ionic liquid 1,3-disulfonic acid imidazolium hydrogen sulfate {[Dsim]HSO4} efficiently catalyzes the synthesis of 1,2,4,5-tetrasubstituted imidazoles via the one-pot multi-component condensation of benzyl with aldehydes, primary amines and ammonium acetate at 90 8C under solvent-free conditions. Dual hydrogen-bond donors can be used to direct the assembly of this catalyst and the efficiency of it.

Simulation of the effect of inclusions length and angle on the failure behavior of concrete structure under 3D compressive test: Experimental test and numerical simulation

Mohammad Saeed Amini,Vahab Sarfarazi,Kaveh Asgari,Xiao Wang,Mojtaba Moheb Hoori 국제구조공학회 2023 Steel and Composite Structures, An International J Vol.46 No.1

Man-made structure materials like concrete usually contain inclusions. These inclusions affect the mechanical properties of concrete. In this investigation, the influence of inclusion length and inclination angle on three-dimensional failure mechanism of concrete under uniaxial compression were performed using experimental test and numerical simulation. Approach of acoustic emission were jointly used to analyze the damage and fracture process. Besides, by combining the stress–strain behavior, quantitative determination of the thresholds of crack stress were done. concrete specimens with dimensions of 120 mm × 150 mm × 100 mm were provided. One and two holes filled by gypsum are incorporated in concrete samples. To build the inclusion, firstly cylinder steel tube was pre-inserting into the concrete and removing them after the initial hardening of the specimen. Secondly, the gypsum was poured into the holes. Tensile strengths of concrete and gypsum were 2.45 MPa and 1.5 MPa, respectively. The angle bertween inclusions and axial loadind ary from 0 to 90 with increases of 30. The length of inclusion vary from 25 mm to 100 mm with increases of 25 mm. Diameter of the hole was 20 mm. Entirely 20 various models were examined under uniaxial test. Simultaneous with experimental tests, numerical simulation (Particle flow code in two dimension) were carried out on the numerical models containing the inclusions. The numerical model were calibrated firstly by experimental outputs and then failure behavior of models containing inclusions have been investigated. The angle bertween inclusions and axial loadind vary from 0 to 90 with increases of 15. The length of inclusion vary from 25 mm to 100 mm with increases of 25 mm. Entirely 32 various models were examined under uniaxial test. Loading rate was 0.05 mm/sec. The results indicated that when inclusion has occupied 100% of sample thickness, two tensile cracks originated from boundaries of sample and spread parallel to the loading direction until being integrated together. When inclusion has occupied 75% of sample thickness, four tensile cracks originated from boundaries of sample and spread parallel to the loading direction until being integrated together. When inclusions have occupied 50% and 25% of sample thickness, four tensile cracks originated from boundaries of sample and spread parallel to the loading direction until being integrated together. Also the inclusion was failed by one tensile crack. The compressive strength of samples decease with the decreases of the inclusions length, and inclusion angle had some effects on that. Failure of concrete is mostly due to the tensile crack. The behavior of crack, was affected by the inclusion length and inclusion number.

Surgical management of a failed internal root resorption treatment: a histological and clinical report

Saeed Asgary,Mohammad Jafar Eghbal,Leili Mehrdad,Sanam Kheirieh,Ali Nosrat 대한치과보존학회 2014 Restorative Dentistry & Endodontics Vol.39 No.2

This article presents the successful surgical management of a failed mineral trioxide aggregate (MTA) orthograde obturation of a tooth with a history of impact trauma and perforated internal root resorption. A symptomatic maxillary lateral incisor with a history of perforation due to internal root resorption and nonsurgical repair using MTA was referred. Unintentional overfill of the defect with MTA had occurred 4 yr before the initial visit. The excess MTA had since disappeared, and a radiolucent lesion adjacent to the perforation site was evident radiographically. Surgical endodontic retreatment was performed using calcium enriched mixture (CEM) cement as a repair material. Histological examination of the lesion revealed granulation tissue with chronic inflammation, and small fragments of MTA encapsulated within fibroconnective tissue. At the one and two year follow up exams, all signs and symptoms of disease had resolved and the tooth was functional. Complete radiographic healing of the lesion was observed two years after the initial visit. This case report illustrates how the selection of an appropriate approach to treatment of a perforation can affect the long term prognosis of a tooth. In addition, extrusion of MTA into a periradicular lesion should be avoided.

Biodiversity status of Tulipa (Liliaceae) in Iran inferred from molecular characterization

Davoud Asgari,Alireza Babaei,Mohammad Reza Naghavi,Mahmoud Kiani 한국원예학회 2020 Horticulture, Environment, and Biotechnology Vol.61 No.3

Here, we used data generated from amplifi ed fragment length polymorphism (AFLP) analysis to address the biodiversitystatus and taxonomic relationships among 47 wild accessions representing 9 species of the genus Tulipa in Iran. A high levelof genetic diversity within the genus was observed; the most distant taxa were T. humilis and T. schrenkii , while the highestdegree of similarity was found between T. montana and T. bifl ora . Twelve AFLP primer sets amplifi ed 342 fragments, ofwhich 304 were polymorphic (88.1%). The average number of polymorphic bands per AFLP primer pair was 28.5. A hierarchicalcluster analysis was carried out on the genetic profi le of the taxa, and the results mostly reconfi rmed the recognizedtaxonomy of the genus. However, we found evidence for recognition of a new subgenus for T. biebersteiniana .

Nonlinear Feature Transformation and Genetic Feature Selection: Improving System Security and Decreasing Computational Cost

Saeid Asgari Taghanaki,Mohammad Reza Ansari,Behzad Zamani Dehkordi,Sayed Ali Mousavi 한국전자통신연구원 2012 ETRI Journal Vol.34 No.6

Intrusion detection systems (IDSs) have an important effect on system defense and security. Recently, most IDS methods have used transformed features, selected features,or original features. Both feature transformation and feature selection have their advantages. Neighborhood component analysis feature transformation and genetic feature selection (NCAGAFS) is proposed in this research. NCAGAFS is based on soft computing and data mining and uses the advantages of both transformation and selection. This method transforms features via neighborhood component analysis and chooses the best features with a classifier based on a genetic feature selection method. This novel approach is verified using the KDD Cup99 dataset, demonstrating higher performances than other well-known methods under various classifiers have demonstrated.

Synthesis and physicochemical characterizations of nanostructured Pd/carbon-clinoptilolite-CeO2 catalyst for abatement of xylene from waste gas streams at low temperature

Zeinab Jamalzadeh,Mohammad Haghighi,Nazli Asgari 한국공업화학회 2014 Journal of Industrial and Engineering Chemistry Vol.20 No.5

Xylene removal from waste gas streams was carried out via catalytic oxidation over Pd/carbon-clinoptilolite-CeO2. The synthesized samples were characterized by XRD, FESEM, BET, FTIR and TG techniques. The XRD patterns confirmed the formation of nano ceria with an average crystallite size of 11.6 nm. FESEM results indicated a good morphology for prepared carbon with deep pores, confirmed structure modification of zeolite, and showed that nanocatalyst has nanometric particles with an average size of 60.85 nm. Reaction data illustrated 98% abatement of xylene at 250 ℃. The stability test of catalyst demonstrated that the removal efficiency has remained constant for 1200 min.

Covalent Immobilization of Trypsin on a Novel Aldehyde-Terminated PAMAM Dendrimer

Aliasghar Hamidi,Mohammad R. Rashidi,Davoud Asgari,Ayuob Aghanejad,Soodabeh Davaran 대한화학회 2012 Bulletin of the Korean Chemical Society Vol.33 No.7

Dendrimers are a novel class of nonlinear polymers and due to their extensive applications in different fields, called versatile polymers. Polyamidoamine (PAMAM) dendrimers are one of the most important dendrimers that have many applications in nanobiotechnology and industry. Generally aldehyde terminated dendrimers are prepared by activation of amine terminated dendrimers by glutaraldehyde which has two problems, toxicity and possibility of crosslink formation. In this study, novel aldehyde-terminated PAMAM dendrimer was prepared and used for covalent immobilization of trypsin by the aim of finding a special reagent which can prevent crosslinking and deactivation of the enzyme. For this purpose aminoacetaldehydedimethylacetal (AADA) was used as spacer group between aldehyde-terminated PAMAM and trypsin.The findings of this study showed that immobilization of trypsin not only resulted higher optimal temperature, but also increased the thermal stability of the immobilized enzyme in comparison to the free enzyme.

Covalent Immobilization of Trypsin on a Novel Aldehyde-Terminated PAMAM Dendrimer

Hamidi, Aliasghar,Rashidi, Mohammad R.,Asgari, Davoud,Aghanejad, Ayuob,Davaran, Soodabeh Korean Chemical Society 2012 Bulletin of the Korean Chemical Society Vol.33 No.7

Dendrimers are a novel class of nonlinear polymers and due to their extensive applications in different fields, called versatile polymers. Polyamidoamine (PAMAM) dendrimers are one of the most important dendrimers that have many applications in nanobiotechnology and industry. Generally aldehyde terminated dendrimers are prepared by activation of amine terminated dendrimers by glutaraldehyde which has two problems, toxicity and possibility of crosslink formation. In this study, novel aldehyde-terminated PAMAM dendrimer was prepared and used for covalent immobilization of trypsin by the aim of finding a special reagent which can prevent crosslinking and deactivation of the enzyme. For this purpose aminoacetaldehydedimethylacetal (AADA) was used as spacer group between aldehyde-terminated PAMAM and trypsin.The findings of this study showed that immobilization of trypsin not only resulted higher optimal temperature, but also increased the thermal stability of the immobilized enzyme in comparison to the free enzyme.

Dysarthric speaker identification with different degrees of dysarthria severity using deep belief networks

Aref Farhadipour,Hadi Veisi,Mohammad Asgari,Mohammad Ali Keyvanrad 한국전자통신연구원 2018 ETRI Journal Vol.40 No.5

Dysarthria is a degenerative disorder of the central nervous system that affects the control of articulation and pitch; therefore, it affects the uniqueness of sound produced by the speaker. Hence, dysarthric speaker recognition is a challenging task. In this paper, a feature‐extraction method based on deep belief networks is presented for the task of identifying a speaker suffering from dysarthria. The effectiveness of the proposed method is demonstrated and compared with well‐known Mel‐frequency cepstral coefficient features. For classification purposes, the use of a multi‐layer perceptron neural network is proposed with two structures. Our evaluations using the universal access speech database produced promising results and outperformed other baseline methods. In addition, speaker identification under both text‐dependent and text‐independent conditions are explored. The highest accuracy achieved using the proposed system is 97.3%.