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Seismic surface waves with low frequencies results in higher effects. The aim of the utilization of seismic metamaterials is to prevent or minimize the effects of this waves particularly wide frequency ranges. This study presents the investigation of the reducing effects of seismic metamaterials composed of circular array concrete piles on surface waves. The investigation of circular array concrete piles has been carried out numerically between 5-15 Hz. The effectiveness of the periodic structure has been observed numerically for fields including metamaterials by comparing empty field. The observations have been depicted according to transmission losses for two cases by using finite element method (FEM) simulations. The wave propagation also presented at the related frequencies where the transmission losses seen. Effective dimensions of radius and length of the structures have been obtained by using parametric approach. It has been proved numerically that the suggested concrete piles reduces the hazardous effects of surface waves.

In this study, the band structure and transmission spectra in multiferroic based Sierpinski-carpet phononic crystal are investigated based on finite element simulation. In order to obtain the band structure of the phononic crystal (PnC), the Floquet periodicity conditions were applied to the sides of unit cell. The square lattice PnC consists of various piezoelectric inclusion in a rubber matrix with circular and triangular cross section. [ABSTRACT FROM AUTHOR]

Temporally periodic photonic crystals develop an ω-k dispersion relation with momentum band gaps. While conventional photonic crystals induce forbidden bands in the frequency spectrum of photons, photonic time crystals create forbidden regions in the momentum spectrum of photons. This effect allows for enhanced control over many optical processes that require both photonic energy and momentum conservations such as nonlinear harmonic generation. The simulation results show that more intensive scatter fields can obtained in photonic space time crystal. Also, we investigate topological phase transitions of photonic time crystals systems. [ABSTRACT FROM AUTHOR]

Byline: H. Duygu Ozsoy, Halil Kumbur, Zafer Ozer Adsorption of copper (II) ions to untreated peanut hulls and untreated Pinus brutia sawdust was investigated as a function of the contact time, amount of adsorbents, initial pH, temperature and initial metal ion concentration. Adsorption efficiency was increased by increasing contact time, amount of adsorbents and decreasing initial metal ion concentration. The optimum adsorption conditions were obtained at pH 5.0. Experimental results indicate that peanut hulls are a more effective adsorbent than Pinus brutia sawdust for the removal of Cu (II) from aqueous solutions. The isothermal data of peanut hulls could be well described by the Langmuir and Freundlich equations.

This paper presents the design, modeling and finite element model simulation of a micro-electromechanical system based on the ternary ferroelectric compounds and paratellurite. The dynamic behavior of the sensor structure is described by the super position of its dominant vibration mode shapes. The resulting model still considers all the physical domains and is even able to capture nonlinear phenomena, such as the stress stiffening of constraint structures or frequency and stiffening caused by squeezed gas in the sensor cell. Process induced and thermally induced residual stresses and the resulting deformation of the transducer elements are considered. [ABSTRACT FROM PUBLISHER]

Background & objectives: It has been shown that joint damage due to subclinical synovitis progresses despite apparent clinical remission in rheumatoid arthritis (RA). Hence, finding more objective methods to investigate subclinical synovitis has become a current issue. Ultrasonography (US) has been among the most investigated methods. This study was conducted to detect whether there was subclinical inflammation in RA patients in clinical remission by power Doppler ultrasonography (PDUS) and to evaluate the effects of this inflammation on upper extremity function. Methods: Forty five RA patients fulfilled the remission criteria of disease activity score 28 using erythrocyte sedimentation rate (DAS28-ESR), were enrolled in the study. Bilateral wrist, 2nd and 3th metacarpophalangeal and proximal interphalangeal joints and 2nd and 5th metatarsophalangeal joints were examined by PDUS. Upper extremity function was assessed with Michigan Hand Outcomes Questionnaire (MHQ) and handgrip strength. The pain was evaluated by visual analogue scale (VAS). Results: In 29 of 45 RA patients in clinical remission, synovitis was detected by PDUS at least in one joint. VAS and DAS28-ESR scores were significantly lower and total MHQ, some subgroup scores of MHQ (overall hand function, activity of daily living and work performance) and grip strength of the dominant hand were higher in patients with PD signal negativity. Interpretation & conclusions: PDUS showed a crucial role in determining the subclinical synovitis. Subclinical synovitis negatively affects the upper extremity function. Ultrasound-defined remission may be considered for good functional status and real remission in patients with RA. [ABSTRACT FROM AUTHOR]

Objective: Fibromyalgia (FM) is a common disorder that is associated with a high rate of psychiatric co-morbidity (depression, anxiety disorders), its association with post-traumatic stress disorder (PTSD), alexithymia and dissociative symptoms has not been sufficiently investigated. The present study evaluated three hypotheses: 1- That a high frequency of traumatic experiences and PTSD would be observed in patients with FM. 2- That FM would be associated with symptoms of alexithymia and somatoform dissociation. 3- That trauma negatively affects the clinical parameters of FM. Methods: Fifty-six consecutive patients with FM admitted to the outpatient department were enrolled in this study after providing informed consent. Forty-six patients with rheumatoid arthritis (RA) were enrolled as controls. Participants completed the Somatoform Dissociation Questionnaire (SDQ), the Post-traumatic Diagnostic Scale (PDS), the Toronto Alexithymia Scale (TAS), and The Childhood Trauma Questionnaire (CTQ). The impact of FM was measured with the Fibromyalgia Impact Questionnaire (FIQ). Results: The number of patients reporting at least one traumatic event was higher in the FM (19, 33.9%) than in the RA (6, 13%) (×2= 5.9, p= 0.015) group. Post-traumatic stress disorder (PTSD) was found in six (10.7%) out of 56 subjects with FM. In the RA group, no patients met the criteria for PTSD. Current PTSD prevalence was higher in the FM than in the RA group. Among those with FM group and traumatic experiences, FIQ scores were higher in patients with than without PTSD (p= 0.02). FM patients had significantly higher scores than did RA patients on the CTQ, SDQ and TAS. Conclusion: PTSD, alexithymia, and somatoform dissociative symptoms are common in FM patients. It is important to identify and treat PTSD, alexithymia, and dissociative symptoms in FM patients as these can affect the patients' health. Taken together, results from previous studies with adults and those from the present study suggest that treatment of PTSD, alexithymia and dissociative symptoms positively influences the levels of pain and FM-related disability in FM patients. Our findings support the idea that trauma-oriented approaches are important in the treatment of FM. [ABSTRACT FROM AUTHOR]