Voltage Type First Order All-Pass Filter Employing Fully Differential Current Feedback Operational Amplifier and Quadrature Oscillator

DergiPark: 245968trakyafbdAn improvement voltage mode first order all-pass filter configuration is proposed. The presented circuit uses a single fully differential current feedback operational amplifier (FDCFOA), resistors and a grounded capacitor. High input impedance of the proposed filter enables the circuit to be cascaded without additional buffers. It does not impose any component matching constraint in analog signal processing circuits. Also higher order all-pass filter could be achieved by cascading the proposed all-pass sections. In order to demostrate the performance of the proposed filter a new voltage mode oscillator is introduced as an application example. Furthermore the theoretical results are verified with SPICE simulations using a CMOS realization of FDCFOAGerilim modunda birinci dereceden tüm geçiren yeni bir süzgeç devresi önerilmiştir. Önerilen devrede bir tam diferansiyel akım geribeslemeli işlemsel kuvvetlendirici, dirençler ve topraklı bir kapasite bulunmaktadır. Önerilen devrenin yüksek giriş direnci, ek tampon kullanılmadan devrenin kaskad bağlanabilmesini sağlamaktadır. Analog işaret işleme devrelerinde herhangi bir eleman denkleştirme koşuluna gerek duyulmamaktadır. Aynı zamanda daha yüksek dereceden tüm geçiren süzgeçler önerilen birinci dereceden süzgeçler kaskad bağlanarak elde edilebilmektedir. Önerilen süzgecin başarımını göstermek amacıyla, bir uygulama örneği olarak gerilim modunda yeni bir osilatör tanıtılmıştır. Bundan başka teorik sonuçlar, FDCFOA elemanının CMOS gerçeklenmesi kullanılarak SPICE benzetimleriyle doğrulanmıştır

DVCC Based Current-Mode First Order All-Pass Filter and Quadrature Oscillator

DergiPark: 245946trakyafbdA current mode first-order all-pass filter configuration is proposed. The presented circuit uses a single differential voltage current conveyor (DVCC), a capacitor and resistors. High output impedance of the proposed filter enables the circuit to be cascaded without additional buffers. To demonstrate the performance of the proposed filter a new current mode quadrature oscillator is given as an application example. Oscillator is implemented through the proposed first order all-pass filter and integrator as the building blocks. Furthemore the effects of tracking errors of the DVCC on oscillation condition and frequency are investigated. The theoretical results are verified with PSPICE simulations using a new CMOS realization of DVCC

Analysis of water loss management performance of water utilities and development of basic performance ındicator analysis tool

Su kayıp yönetiminde, sistem davranışının izlenmesi ve sistem performansının uygun göstergelere göre analiz edilmesi işletme koşullarının iyileştirilmesi açısından oldukça önemlidir. Ancak bu analizlerin doğru, düzenli, sistematik ve hassas bir şekilde yapılması için uygun hesaplama araçlarının kullanılması gerekir. Bu nedenle, bu çalışmada kentsel su kayıp yönetiminde su kayıpları ile mücadelede süreç performansının analiz edilmesi ve izlenmesi amacıyla literatür esas alınarak en uygun göstergeler belirlenmiştir. Bu göstergelerin belirlenmesinde Uluslararası Su Birliği (IWA) ve diğer kuruluşlar tarafından önerilen göstergeler detaylı bir şekilde analiz edilmiş ve su kayıp yönetimi açısından en uygun göstergelerin seçilmiştir. Belirlenen bu performans göstergelerinin sistematik bir şekilde hesaplanması ve performansın izlenmesi için web tabanlı “GGS temel performans analizi hesaplama aracı” geliştirilmiştir. Bu hesaplama aracı temel olarak, hacimsel ve yüzdesel göstergeleri, servis bağlantı ve hat uzunluğu başına göstergeleri, idari ve fiziki kayıp, ekonomik ve maliyet, arıza ve şebeke rehabilitasyon göstergelerini içermektedir. Bu hesaplama aracının detayları paylaşılmış, sağladığı avantajlar tartışılmış ve örnek veriler için analiz yapılmıştır. Geliştirilen bu hesaplama aracının, İdarelerin su kayıp yönetimi ve bileşenleri açısından performansının analiz edilmesi, izlenmesi ve aktif kaçak kontrolü faaliyetleri için süreç performansının değerlendirilmesinde önemli katkılar sağlayacağı düşünülmektedir.In water loss management, monitoring system behavior and analyzing system performance according to appropriate indicators is very important for improving operating conditions. However, appropriate calculation tools should be used to make these analyzes accurately, regularly, systematically and precisely. Therefore, in this study, the most appropriate indicators were determined based on the indicators proposed IWA and other organizations in literature in order to analyze and monitor the process performance in water loss management. A web-based "GGS basic performance analysis calculation tool" has been developed to systematically calculate these indicators and monitor performance. This tool basically includes volumetric and percentage indicators, service connection and per line length indicators, administrative and physical loss, economic and cost, failure and network rehabilitation indicators. The details of this tool were detailed, its advantages were discussed by analyzing of sample data set. It is believed that this analysis tool developed in this study will provide significant contributions to the analysis and monitoring of the performance of the Utilities in terms of water loss management and its components, and to evaluate the process performance for active leakage control activitie

Su ve Kanalizasyon İdarelerinde Kıyaslamalı Performans Analizi için Web Tabanlı Hesaplama Araçlarının Geliştirilmesi

Uzun dönemli sürdürülebilir su ve atıksu yönetimi için sistem bileşenlerinin düzenli olarak izlenmesi ve performans analizinin yapılması gerekir. Bunun için verisi ölçülebilir, uygun, uygulanabilir göstergelerin kullanılması oldukça önemlidir. Bu çalışmada su ve atıksu yönetimi açısından performans analizi ve kıyaslaması yapılması amacıyla kullanılan göstergelerin doğru ve sistematik bir şekilde hesaplanması için web tabanlı hesaplama aracı geliştirilmiştir. Geliştirilen bu hesaplama aracı temel olarak IWA, AWWA, IBNET ve SUEN tarafından önerilen göstergeleri hesaplayan dört farklı modülden oluşmaktadır. Bu modüllerde hesaplanmak istenen ana ve alt göstergeler kullanıcı tarafından seçilebilmektedir. Böylece sadece verisi olan, uygun ve uygulanabilir göstergelerin hesaplanması mümkün olmaktadır. Ayrıca seçilen ana ve alt göstergelerin etki düzeyi (ağırlık katsayısı) eşit bir şekilde dağıtıldığı gibi kullanıcı tarafından her bir gösterge için ağırlık tanımlaması da yapılabilmektedir. Hesaplama modüllerinde veriler ve ağırlık katsayıları çarpılarak ağırlıklı toplam puanlar hesaplanmakta ve sistem için toplam performans indisi elde edilmektedir. Bu hesaplama aracının bu özellikleriyle, Su İdarelerinde karar vericiler ve teknik personeller için referans oluşturma potansiyelinin olduğu düşünülmektedir

Contribution of Endorectal Ultrasound, Magnetic Resonance Imaging and Positron Emission Tomography to Operation Strategy in Rectal Cancer

Objective:Colorectal cancer is the most common type of cancer in the gastrointestinal tract. Preoperative staging is important for applying appropriate treatment modalities. The role of endorectal ultrasonography (ERUS), magnetic resonance imaging (MRI) and positron emission-computed tomography (PET-CT) in rectal cancer patients was evaluated.Method:In this study, between October 2010-April 2012, 30 patients who were diagnosed as rectal cancer clinically and histopathologically were evaluated with ERUS, MRI and PET-CT preoperatively and results were compared with histopathologic findings.Results:Between October 2010-April 2012, 30 patients who were diagnosed as rectal cancer with biopsy in Bezmialem University Medical Faculty Hospital General Surgery Department were included in this study [20 male (66.6%), 10 female (33.3%) and their ages are 38-75 years old, 21 of them received neoadjuvant treatment and 9 of them did not received]. All patients were evaluated with MRI, ERUS and PETCT preoperatively. Rectal cancer patients who are primarily operated from rectal adenocarcinoma were included in this study. For T staging, preoperative MRI, ERUS and PET-CT staged 9 (31%), 12 (41%) and 12 (40%) of 30 patients accurately, respectively. For N staging, preoperative MRI, ERUS and PET-CT staged 15 (51%), 16 (55.1%) and 17 (56.6%) of 30 patients accurately, respectively. In comparison to other modalities, PET-CT did not yield a significant difference in staging and did not change operation strategy. PET-CT detected distant metastasis in 3 patients. One of them was liver and two of them were lung metastasis. Biopsies from mass predicted as lung metastasis did not result as metastasis. PET-CT has high rates of false positivity to detect distant metastasis. In statistical analysis, significant p-values for evaluation could not be obtained.Conclusion:Efficacy of routine use of PET-CT on staging, evaluation of T, N and extramesorectal spread could not be shown

Green Synthesis of Silver Nanoparticles from Allium cepa L. Peel Extract, Their Antioxidant, Antipathogenic, and Anticholinesterase Activity

The present work deals with the green synthesis and characterization of silver nanoparticles (AgNPs) using Allium cepa (yellowish peel) and the evaluation of its antimicrobial, antioxidant, and anticholinesterase activities. For the synthesis of AgNPs, peel aqueous extract (200 mL) was treated with a 40 mM AgNO3 solution (200 mL) at room temperature, and a color change was observed. In UV-Visible spectroscopy, an absorption peak formation at ~439 nm was the sign that AgNPs were present in the reaction solution. UV-vis, FE-SEM, TEM, EDX, AFM, XRD, TG/DT analyses, and Zetasizer techniques were used to characterize the biosynthesized nanoparticles. The crystal average size and zeta potential of AC-AgNPs with predominantly spherical shapes were measured as 19.47 ± 1.12 nm and −13.1 mV, respectively. Pathogenic microorganisms Bacillus subtilis, Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, and Candida albicans were used for the Minimum Inhibition Concentration (MIC) test. When compared to tested standard antibiotics, AC-AgNPs demonstrated good growth inhibitory activities on P. aeuruginosa, B. subtilis, and S. aureus strains. In vitro, the antioxidant properties of AC-AgNPs were measured using different spectrophotometric techniques. In the β-Carotene linoleic acid lipid peroxidation assay, AC-AgNPs showed the strongest antioxidant activity with an IC50 value of 116.9 µg/mL, followed by metal-chelating capacity and ABTS cation radical scavenging activity with IC50 values of 120.4 µg/mL and 128.5 µg/mL, respectively. The inhibitory effects of produced AgNPs on the acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) enzymes were determined using spectrophotometric techniques. This study provides an eco-friendly, inexpensive, and easy method for the synthesis of AgNPs that can be used for biomedical activities and also has other possible industrial applications

The Investigation of the Chemical Composition and Applicability of Gold Nanoparticles Synthesized with Amygdalus communis (Almond) Leaf Aqueous Extract as Antimicrobial and Anticancer Agents

The current work’s main objective was to determine the chemical composition of Amygdalus communis (AC) leaf extract and examine the antibacterial and cytotoxic properties of biosynthesized gold nanoparticles (AuNPs). The chemical composition of AC leaf extract was determined using LC-ESI/MS/MS to detect compounds that may be responsible for the reducing, stabilizing, and capping steps in the synthesis of nanoparticles and their biological activities. The AC-AuNPs were spherical, with a particle size lower than 100 nm and a face-centered cubic structure. The EDX spectrum confirmed the formation of AuNPs and a negative zeta potential value (−27.7 mV) suggested their physicochemical stability. The in vitro cytotoxic efficacy of the AC-AuNPs against colorectal adenocarcinoma (Caco-2), glioma (U118), and ovarian (Skov-3) cancer cell lines and human dermal fibroblasts (HDFs) was evaluated by MTT assay. CaCo-2 cell proliferation was effectively inhibited by the AC-AuNPs at concentrations between 25 and 100 g mL−1. The AC-AuNPs exerted preeminent antimicrobial activity against Bacillus subtilis with an MIC of 0.02 μg/mL, whilst good activity was shown against Staphylococcus aureus bacteria and Candida albicans yeast with an MIC of 0.12 μg/mL. Ultimately, the results support the high antibacterial and anticancer potential of biosynthesized AuNPs from AC leaf extract