Uterine smooth muscle tumor of uncertain malignant potential: fertility and clinical outcomes

Hanifi Şahin,Funda Karatas,Gonca Coban,Özlem Özen,Özlem Erdem,Mehmet Anıl Onan,Ali Ayhan 대한부인종양학회 2019 Journal of Gynecologic Oncology Vol.30 No.4

Objective: In this study, we aimed to evaluate the clinicopathological features, obstetric, and oncological outcomes of patients diagnosed with a uterine smooth muscle tumors of uncertain malignant potential (STUMP). Methods: A dual-institutional, database review was carried out to screen patients with STUMP who were treated with upfront surgery between January 2006 and December 2017. Data including age at the time of diagnosis, recurrence rate, disease-free survival, overall survival, and fertility outcomes were retrospectively analyzed. Results: Fifty-seven patients with STUMPs were included in the study. The median age at the time of diagnosis was 42 (range, 16 to 75) years. The median follow-up was 57 (range, 16 to 125) months. Eight patients (14%) had recurrence during follow-up. Recurrent STUMPs were seen in seven patients and leiomyosarcoma after 14 months in one patient. Seven patients with a recurrent STUMP survived, while the remaining patient died. Recurrence rates were similar for women who underwent myomectomy and those who underwent hysterectomy. The presence of uterine localization of tumor (subserosal vs intramural-submucosal) statistically significantly affected recurrence rates (odds ratio=5.72; 95% confidence interval=1.349–24.290; p=0.018). Ten of 27 patients who underwent myomectomy for uterine myoma had fertility desire. Seven pregnancies were recorded. Conclusions: Our study results suggest that fertility-sparing approaches are feasible in patients with STUMP, although recurrence may be seen.

A new four-unknown refined theory based on modified couple stress theory for size-dependent bending and vibration analysis of functionally graded micro-plate

Lemya Hanifi Hachemi Amar,Abdelhakim Kaci,Redha Yeghnem,Abdelouahed Tounsi 국제구조공학회 2018 Steel and Composite Structures, An International J Vol.26 No.1

This work investigates a novel plate formulation and a modified couple stress theory that introduces a variable length scale parameter is presented to discuss the static and dynamic of functionally graded (FG) micro-plates. A new type of third-order shear deformation theory of Reddy that use only 4 unknowns by including undetermined integral variables is proposed in this study. The equations of motion are derived from Hamilton’s principle. Analytical solutions are obtained for a simply supported micro-plate. Numerical examples are presented to examine the effect of the length scale parameter on the responses of micro-plates. The obtained results are compared with the previously published results to demonstrate the correctness of the present formulation.

Buckling analysis of FG plates via 2D and quasi-3D refined shear deformation theories

Lemya Hanifi Hachemi Amar,Fouad Bourada,Abdelmoumen Anis Bousahla,Abdelouahed Tounsi,Kouider Halim Benrahou,Hind Albalawi,Abdeldjebbar Tounsi 국제구조공학회 2023 Structural Engineering and Mechanics, An Int'l Jou Vol.85 No.6

In this work, a novel combined logarithmic, secant and tangential 2D and quasi-3D refined higher order shear deformation theory is proposed to examine the buckling analysis of simply supported uniform functionally graded plates under uniaxial and biaxial loading. The proposed formulations contain a reduced number of variables compared to others similar solutions. The combined function employed in this study ensures automatically the zero-transverse shear stresses at the free surfaces of the structure. Various models of the material distributions are considered (linear, quadratic, cubic inverse quadratic and power-law). The differentials stability equations are derived via virtual work principle with including the stretching effect. The Navier’s approach is applied to solve the governing equations which satisfying the boundary conditions. Several comparative and parametric studies are performed to illustrates the validity and efficacity of the proposed model and the various factors influencing the critical buckling load of thick FG plate.

Experimental study on axial response of different pile materials in organic soil

Canakci, Hanifi,Hamed, Majid Techno-Press 2017 Geomechanics & engineering Vol.12 No.6

Sixty four tests were performed in a steel tank to investigate the axial responses of piles driven into organic soil prepared at two different densities using a drop hammer. Four different pile materials were used: wood, steel, smooth concrete, and rough concrete, with different length to diameter ratios. The results of the load tests showed that the shaft load capacity of rough concrete piles continuously increased with pile settlement. In contrast, the others pile types reached the ultimate shaft resistance at a settlement equal to about 10% of the pile diameter. The ratios of base to shaft capacities of the piles were found to vary with the length to diameter ratio, surface roughness, and the density of the organic soil. The ultimate unit shaft resistance of the rough concrete pile was always greater than that of other piles irrespective of soil condition and pile length. However, the ultimate base resistance of all piles was approximately close to each other.

On the size-dependent behavior of functionally graded micro-beams with porosities

Lemya Hanifi Hachemi Amar,Abdelhakim Kaci,Abdelouahed Tounsi 국제구조공학회 2017 Structural Engineering and Mechanics, An Int'l Jou Vol.64 No.5

In this work, a new hyperbolic shear deformation beam theory is proposed based on a modified couple stress theory (MCST) to investigate the bending and free vibration responses of functionally graded (FG) micro beam made of porous material. This non-classical micro-beam model introduces the material length scale coefficient which can capture the size influence. The non-classical beam model reduces to the classical beam model when the material length scale coefficient is set to zero. The mechanical material properties of the FG micro-beam are assumed to vary in the thickness direction and are estimated through the classical rule of mixture which is modified to approximate the porous material properties with even and uneven distributions of porosities phases. Effects of several important parameters such as power-law exponents, porosity distributions, porosity volume fractions, the material length scale parameter and slenderness ratios on bending and dynamic responses of FG micro-beams are investigated and discussed in detail. It is concluded that these effects play significant role in the mechanical behavior of porous FG micro-beams.

Physico-chemical and mineralogical study of ancient mortars used in Harran area (Turkey)

Binici, Hanifi,Akcan, Mehmet,Aksogan, Orhan,Resatoglu, Rifat Techno-Press 2017 Advances in concrete construction Vol.5 No.6

Very limited studies have been accomplished concerning the historical structures around Harran area. Collected mortar samples from the historic structures in the area were tested to explore their mechanical, chemical and mineralogical properties. Mortar samples from three different points of each historical structure were taken and specified in accordance with the related standards taking into consideration their mechanical, chemical and mineralogical properties. By means of SEM-EDX the presence of organic fibres and calcite, quartz, plagioclase and muscovite minerals has been examined. Additionally, by means of XRF analysis, oxide ($SiO_2$, $Al_2O_3$, and $Fe_2O_3$) percentages of mortar ingredients have been specified, also. According to the test results obtained, it was confirmed that the mortars had densities ranging between $1.51-2.10g/cm^3$, porosity values ranging between 8.89-35.38% and compressive strengths ranging between 5.02-5.90 MPa. Specimen HU, which has the highest durability and lowest water absorption and porosity, was the mortar taken from the most intact building in the mosque complex. This result is most likely due to the very little fine aggregate content of HU. In contrast, HUC mortars with a small amount of fine particles and brick contents yielded slightly lower compressive strengths. The interesting point of this study is the mineralogical analysis results and especially the presence of ettringite in these historic mortars linked to the use of pozzolanic materials. Survival of these historic structures in Harran Area through centuries of use and, also, having been subjected to many earthquakes can probably be explained by these properties of the mortars.

Soil stabilization of clay with lignin, rice husk powder and ash

Canakci, Hanifi,Aziz, Aram,Celik, Fatih Techno-Press 2015 Geomechanics & engineering Vol.8 No.1

This article presents the result of laboratory study conducted on expansive soil specimens treated with lignin, rice husk powder (RHP) and rice husk ash (RHA). The amount of lignin produced from paper industry and RHP were varied from 0 to 20% and RHA from 0 to 10% by weight. The treated specimens were subjected to unconfined compressive strength (UCS),swelling test and Atterberg limit tests. The effect of additives on UCS and atterberg limit test results were reported. It was observed that the additives and curing duration had a significant effect on the strength value of treated specimens. Generally (except the sample treated with 20% RHP for 3-day) with increasing additive and curing duration the UCS value increases. A RHP content of 15% was found to be the optimum with regard to 3-day cure UCS.

Optimization of hybrid composite plates using Tsai-Wu Criteria

Mehmet Hanifi Doğru,İbrahim Göv,Eyüp Yeter,Kürşad Göv 국제구조공학회 2023 Structural Engineering and Mechanics, An Int'l Jou Vol.88 No.4

In this study, previously developed algorithm is used for Optimization of hybrid composite plates using Tsai-Wu criteria. For the stress-based Design Optimization problems, Von-Mises stress uses as design variable for isotropic materials. Maximum stress, maximum strain, Tsai Hill, and Tsai-Wu criteria are generally used to determine failure of composite materials. In this study, failure index value is used as design variable in the optimization algorithm and Tsai-Wu criteria is utilized to calculate this value. In the analyses, commonly used design domains according to different hybrid orientations are optimized and results are presented. When the optimization algorithm was applied, 50% material reduction was obtained without exceeding allowable failure index value.

Bending analysis of porous microbeams based on the modified strain gradient theory including stretching effect

Lemya Hanifi Hachemi Amar,Abdelhakim Kaci,Aicha Bessaim,Mohammed Sid Ahmed Houari,Abdelouahed Tounsi 국제구조공학회 2024 Structural Engineering and Mechanics, An Int'l Jou Vol.89 No.3

In this paper, a quasi-3D hyperbolic shear deformation theory for the bending responses of a functionally graded (FG) porous micro-beam is based on a modified couple stress theory requiring only one material length scale parameter that can capture the size influence. The model proposed accounts for both shear and normal deformation effects through an illustrative variation of all displacements across the thickness and satisfies the zero traction boundary conditions on the top and bottom surfaces of the micro-beam. The effective material properties of the functionally graded micro-beam are assumed to vary in the thickness direction and are estimated using the homogenization method of power law distribution, which is modified to approximate the porous material properties with even and uneven distributions of porosity phases. The equilibrium equations are obtained using the virtual work principle and solved using Navier’s technique. The validity of the derived formulation is established by comparing it with the ones available in the literature. Numerical examples are presented to investigate the influences of the power law index, material length scale parameter, beam thickness, and shear and normal deformation effects on the mechanical characteristics of the FG micro-beam. The results demonstrate that the inclusion of the size effects increases the microbeams stiffness, which consequently leads to a reduction in deflections. In contrast, the shear and normal deformation effects are just the opposite.

Fabrication of thin porous electrolyte-supported tubular fuel cells using slip casting

Amir Reza Hanifi,Alireza Torabi,Alyssa Shinbine,Thomas H. Etsell,Partha Sarkar 한양대학교 세라믹연구소 2011 Journal of Ceramic Processing Research Vol.12 No.3

In the current research the third generation of tubular solid oxide fuel cells (SOFCs) which is believed to solve the redox cycling problem is introduced and the cell configuration is discussed. This type of ceramic fuel cell consists of a slip cast porous support of approximately 500 μm thickness coated with a thin dense electrolyte layer both made of calcined YSZ. The porous support can have up to 50% porosity as a result of both the preliminary calcination of YSZ powder and the addition of a pore former. Different parameters that affect the porosity content and thickness of the supports are also studied. It is shown that the short casting time required for high porosity tubes can be controlled by modifying the solid loading of the slip and/or the porosity of the plaster mold. Finally, multiple casting is introduced as a coating method in which the electrolyte layer with the required thickness can be slip cast directly onto the porous support.