Correlation of histological diagnosis and laboratory findings in distinguishing acute appendicitis and lymphoid hyperplasia

Keziban Ucar Karabulut,Hilal Erinanc,Aynur Yonar,Alpaslan Kisinma,Yildiz Ucar 대한외과학회 2022 Annals of Surgical Treatment and Research(ASRT) Vol.103 No.5

Purpose: Acute appendicitis (AA) is one of the most frequent causes of abdominal surgery encountered in emergency rooms. However, reactive lymphoid hyperplasia (RLH) is one of the appendicular pathologies often misdiagnosed. It is quite challenging to distinguish between AA and RLH in terms of planning treatment in an emergency. Therefore, this retrospective study aimed to compare the histological and laboratory findings of AA and RLH. Methods: The retrospective data included in the study were obtained from patients diagnosed with AA. Complete blood count (CBC) and C-reactive protein (CRP) levels of patients with AA and RLH were compared before the surgery based on the histological diagnosis of the patients. Results: A total of 187 patients who previously underwent appendectomy were included in the study. Histopathological examination revealed that 152 patients (81.3%) were diagnosed with AA, and 35 (18.7%) with RLH. While white blood cell count (P < 0.001), neutrophil (P < 0.001), and neutrophil/lymphocyte ratio (P < 0.001) were found to be significantly higher in those with AA; lymphocyte (P = 0.003) and eosinophil counts (P = 0.033) were detected to be significantly higher in those with RLH. CRP level was also significantly higher in those with AA (P = 0.002) Conclusion: We consider that CBC and CRP levels may be predictive in distinguishing between AA and RLH. We consider that these parameters may be valuable in making a distinction between patients before surgery.

A study on determination of target displacement of RC frames using PSV spectrum and energy-balance concept

Ucar, Taner,Merter, Onur,Duzgun, Mustafa Techno-Press 2012 Structural Engineering and Mechanics, An Int'l Jou Vol.41 No.6

The objective of this paper is to present an energy-based method for calculating target displacement of RC structures. The method, which uses the Newmark-Hall pseudo-velocity spectrum, is called the "Pseudo-velocity Spectrum (PSVS) Method". The method is based on the energy balance concept that uses the equality of energy demand and energy capacity of the structure. First, nonlinear static analyses are performed for five, eight and ten-story RC frame structures and pushover curves are obtained. Then the pushover curves are converted to energy capacity diagrams. Seven strong ground motions that were recorded at different soil sites in Turkey are used to obtain the pseudo-acceleration and the pseudo-velocity response spectra. Later, the response spectra are idealised with the Newmark-Hall approximation. Afterwards, energy demands for the RC structures are calculated using the idealised pseudo-velocity spectrum. The displacements, obtained from the energy capacity diagrams that fit to the energy demand values of the RC structures, are accepted as the energy-based performance point of the structures. Consequently, the target displacement values determined from the PSVS Method are checked using the displacement-based successive approach in the Turkish Seismic Design Code. The results show that the target displacements of RC frame structures obtained from the PSVS Method are very close to the values calculated by the approach given in the Turkish Seismic Design Code.

Physical and Comfort Properties of the Hoisery Knit Product Containing Intermingled Nylon Elastomeric Yarn

Ucar, Nuray,Karakas, Hale,Sen, Sibel The Korean Fiber Society 2007 Fibers and polymers Vol.8 No.5

There are several studies related with knitted fabric containing elastomeric yarn. These studies have been carried out only on fabrics containing naked elastomeric yarn, i.e., without intermingling. And most of them have focused on dimensional and extension-recovery properties of the fabric. Of course, intermingling yarn parameters such as number of knots and draw-ratio will affect the properties and performance of the fabrics. This paper presents a study about the effect of draw-ratio and number of knots, which are important parameters in intermingled nylon-elastomeric yarns, on the physical and comfort properties of hosiery knit products. To see the relationship and significance, bivariate correlation analysis and analysis of variance have been carried out. It has been seen that increase of draw ratio and number of knots lead to an increase in dimensional change, stitch density, fabric weight, and lead to a decrease in fabric spirality, abrasion, fabric wicking (wickability in course direction is less than that of wale direction). Fabric thickness increases with an increase in draw ratio and a decrease in number of knots. The number of knots and the draw-ratio do not affect the fabric drying rate. However, an increase in the draw ratio and the number of knots result in an increase in initial water content before beginning the drying process. But, an increase in initial water content is not so high as to affect the drying rate.

Strategic coating of NdFeB magnets with Dy to improve the coercivity of permanent magnets

Ucar, Huseyin,Parker, David S.,Nlebedim, I.C.,McCallum, R.W.,McCall, S.K.,Parans Paranthaman, M. Techno-Press 2015 Advances in materials research Vol.4 No.4

We present a method, supported by theoretical analysis, for optimizing the usage of the critical rare earth element dysprosium in $Nd_2Fe_{14}B$ (NdFeB)-based permanent magnets. In this method, we use Dy selectively in locations such as magnet edges and faces, where demagnetization factors are largest, rather than uniformly throughout the bulk sample. A200 nm thick Dy film was sputtered onto a commercial N-38, NdFeB magnets with a thickness of 3 mm and post-annealed at temperatures from $600-700^{\circ}C$. Magnets displayed enhanced coercivities after post-annealing and as much as a 5 % increase in the energy product, while requiring a total Dy content of 0.06 wt. % - a small fraction of that used in the commercial grade Dy-NdFeB magnets. By assuming all Dy diffused into NdFeB magnets, the improvement in energy product corresponds to a saving of over 1% Dy (critical element). Magnets manufactured using this technique will therefore be higher performing which would potentially broaden the application space of these magnets in the traction motors of hybrid and pure electric vehicles, and wind generators.

Measurement of Fuzz Fibers on Fabric Surface Using Image Analysis Methods

Ucar Nuray,Boyraz Plnar The Korean Fiber Society 2005 Fibers and polymers Vol.6 No.1

Fuzz on the fabrics, which is the fibers protruded from the fabric surface, is very important in view of appearance quality, since it causes unpleasant appearance on the fabrics and also leads to pilling which makes fabric appearance and soft­ness worse. However, fuzz on fabric surface is measured mostly by subjective methods (human vision) rather than objective methods. Thus, in this study, objective method using image analysis techniques has been developed for the measurement of fuzz on fabric surface. Fuzz on the fabric has also been ranked and rated by experts in order to see the reliability of the results obtained from the fuzz measurement. It was observed that correlation coefficient (r) between rating value and objective mea­surement value was 0.9 and this correlation coefficient value confirmed the reliability of this method.

Determination of lateral strength and ductility characteristics of existing mid-rise RC buildings in Turkey

Taner Ucar,Onur Merter,Mustafa Duzgun 사단법인 한국계산역학회 2015 Computers and Concrete, An International Journal Vol.16 No.3

This paper presents a comprehensive work on determination of yield base shear coefficient and displacement ductility factor of three to eight story actual reinforced concrete buildings, instead of using generic frames. The building data is provided by a walkdown survey in different locations of the pilot areas. Very detailed three dimensional models of the selected buildings are generated by using the data provided in architectural and reinforcement projects. Capacity curves of the buildings are obtained from nonlinear static pushover analyses and each capacity curve is approximated with a bilinear curve. Characteristic points of capacity curve, the yield base shear capacity, the yield displacement and the ultimate displacement capacity, are determined. The calculated values of the yield base shear coefficients and the displacement ductility factors for directions into consideration are compared by those expected values given in different versions of Turkish Seismic Design Code. Although having sufficient lateral strength capacities, the deformation capacities of these typical mid-rise reinforced concrete buildings are found to be considerably low.

Distribution of near-fault input energy over the height of RC frame structures and its formulation

Taner Ucar 국제구조공학회 2023 Structural Engineering and Mechanics, An Int'l Jou Vol.85 No.1

Energy-based seismic design and evaluation methods are promising to be involved in the next generation design codes. Accordingly, determining the distribution of earthquake input energy demand among floor levels is quite imperative in order to develop an energy-based seismic design procedure. In this paper, peak floor input energy demands are achieved from relative input energy response histories of several reinforced concrete (RC) frames. A set of 22 horizontal acceleration histories selected from recorded near-fault earthquakes and scaled in time domain to be compatible with the elastic acceleration design spectra of Turkish Seismic Design Code are used in time history analyses. The distribution of the computed input energy per mass values and the arithmetic means through the height of the considered RC frames are presented as a result. It is found that spatial distribution of input energy per mass is highly affected by the number of stories. Very practical yet consistent formulation of distributing the total input energy to story levels is achieved, as a most important contribution of the study.

Derivation of yield force coefficient for RC frames considering energy balance and P-delta effects

Taner Ucar,Onur Merter 국제구조공학회 2021 Structural Engineering and Mechanics, An Int'l Jou Vol.79 No.4

Currently, prominent energy balance concept can efficiently be used to calculate the yield base shear force of structures. Energy balance equation is an additional constraint for the balance of seismic input energy by the energy absorption of the structure. This equation can be defined as the sum of elastic and plastic energies of structural systems using elastic and plastic load-deformation characteristics and the total energy dissipation capacity can finally be equated to the seismic energy demand. The objective of this paper is to present a procedure for the determination of energy-based yield force coefficient of reinforced concrete (RC) frame structures considering P-delta effects. The total of elastic and plastic energies are computed by means of elastic spectral velocity and energy modification factor, which is originally derived for structural systems with geometric nonlinearity. Total inelastic energy of single-degree-of-freedom (SDOF) system is transformed into the total inelastic energy of the multi-degree-of-freedom (MDOF) system using the conversion based on structural dynamics. Plastic energy of MDOF system is formulated after total seismic energy demand is obtained. It is accordingly equated to the total work done by inelastic MDOF structure with P-delta effects and consequently, a dimensionless yield force coefficient is derived. Nonlinear static analyses are performed for selected multi-story RC frames and yield force coefficients are compared with the results of the energy-based formulation. The results show that the proposed formulation taking P-delta effects into account can be effectively used to estimate the yield force coefficient of RC frame structures.

Effect of design spectral shape on inelastic response of RC frames subjected to spectrum matched ground motions

Taner Ucar,Onur Merter 국제구조공학회 2019 Structural Engineering and Mechanics, An Int'l Jou Vol.69 No.3

In current seismic design codes, various elastic design acceleration spectra are defined considering different seismological and soil characteristics and are widely used tool for calculation of seismic loads acting on structures. Response spectrum analyses directly use the elastic design acceleration spectra whereas time history analyses use acceleration records of earthquakes whose acceleration spectra fit the design spectra of seismic codes. Due to the fact that obtaining coherent structural response quantities with the seismic design code considerations is a desired circumstance in dynamic analyses, the response spectra of earthquake records used in time history analyses had better fit to the design acceleration spectra of seismic codes. This paper evaluates structural response distributions of multi-story reinforced concrete frames obtained from nonlinear time history analyses which are performed by using the scaled earthquake records compatible with various elastic design spectra. Time domain scaling procedure is used while processing the response spectrum of real accelerograms to fit the design acceleration spectra. The elastic acceleration design spectra of Turkish Seismic Design Code 2007, Uniform Building Code 1997 and Eurocode 8 are considered as target spectra in the scaling procedure. Soil classes in different seismic codes are appropriately matched up with each other according to VS30 values. The maximum roof displacements and the total base shears of considered frame structures are determined from nonlinear time history analyses using the scaled earthquake records and the results are presented by graphs and tables. Coherent structural response quantities reflecting the influence of elastic design spectra of various seismic codes are obtained.

A study on determination of target displacement of RC frames using PSV spectrum and energy-balance concept

Taner Ucar,Onur Merter,Mustafa Duzgun 국제구조공학회 2012 Structural Engineering and Mechanics, An Int'l Jou Vol.41 No.6

The objective of this paper is to present an energy-based method for calculating target displacement of RC structures. The method, which uses the Newmark-Hall pseudo-velocity spectrum, is called the “Pseudo-velocity Spectrum (PSVS) Method”. The method is based on the energy balance concept that uses the equality of energy demand and energy capacity of the structure. First, nonlinear static analyses are performed for five, eight and ten-story RC frame structures and pushover curves are obtained. Then the pushover curves are converted to energy capacity diagrams. Seven strong ground motions that were recorded at different soil sites in Turkey are used to obtain the pseudo-acceleration and the pseudo-velocity response spectra. Later, the response spectra are idealised with the Newmark-Hall approximation. Afterwards, energy demands for the RC structures are calculated using the idealised pseudo-velocity spectrum. The displacements, obtained from the energy capacity diagrams that fit to the energy demand values of the RC structures, are accepted as the energy-based performance point of the structures. Consequently, the target displacement values determined from the PSVS Method are checked using the displacement-based successive approach in the Turkish Seismic Design Code. The results show that the target displacements of RC frame structures obtained from the PSVS Method are very close to the values calculated by the approach given in the Turkish Seismic Design Code.