Concrete pavement prediction life model based on electrical response of concrete-CNTs sensors under fatigue loading

Structural Health Monitoring (SHM) of important infrastructures such as Portland cement concrete pavements plays a key role in pioneer societies, to guarantee the optimum usability and performance of the infrastructure system. As an example, this is imperative to appraise the destruction level in Portland cement concrete pavements along time as to plan their maintenance with proper actions at the right time. Based on this premise, the goal of this study is to extend an extensive feasibility study to set up a novel approach for SHM of Portland cement concrete pavements and remaining life estimation, based on self-sensing concrete-CNTs sensors added with multi-walled carbon nanotubes (CNTs). The concrete-CNTs sensors are applied as piezoresistive sensors (i.e. to collect information such as weight and species of passing vehicles), or as destruction identification sensors (i.e. to detect crack propagation in the Portland cement concrete pavement). For casting the concrete-CNTs sensors, some parameters are important, such as the number of CNTs, species of surfactant, dispersion quality etc. In this research, the dispersion quality of multi-walled carbon nanotubes in the aqueous phase and cement matrix was experiment examined using Ultraviolet-Visible Spectrophotometry (UV-VIS), Scanning Electron Microscopy (SEM) and mechanical experiments for compressive and flexural strength. The outcomes demonstrated that a new specific surfactant composition (sodiumdodecylbenzene sulfonate (SDS) and superplasticizer carboxylate base (SP-C) with the ratio of 1:9 respectively) could disperse MWCNTs around 64% more than other surfactant combinations indicated in the previous studies while this has enough compatibility with the concrete to omit antifoam in the mixing process and maintain the concrete mechanical specifications pretty constant. To appraise the influences of the main parameters affecting concrete-CNTs sensors function, diverse criteria in static and dynamic loading patterns were defined such as sensitivity of the sensor (Se), the standard deviation of the prediction error, repeatability (Re), cross-correlation (CC) and hysteresis (SSE). The dynamic criteria such as sensitivity, internal repeatability, cross-correlation and hysteresis declared that the dispersion energy levels for the dispersion of MWCNTs have a major impact on enhancing the function of the sensor rather than the number of CNTs. The repeatability criterion, contrariwise, showed that the number of MWCNTs has a major impact on the function of the sensor compared to the dispersion quality (dispersion energy level) of MWCNTs. Consequently, both parameters have to be regarded as relevant. The overall outcomes showed that the sensors fabricated with 0.15 wt% CNTs, superplasticizer and SDS as a surfactant using the maximum dispersion energy level (ultrasonic bath for 2 hours and 90 minutes of ultrasonic probing) have the best function in both static and dynamic load mode. To explore the influences of traffic loads on the pavement, concrete-CNTs sensors were experiment examined under various value of dynamic loads. The outcomes demonstrated that the maximum exterior load applied on the sensor (Fmax) is linearly correlated to the maximum response of the sensor (Smax) via a constant coefficient tagα/tagβ, in which tagα is defined as the slope of the Force vs. Time graph and tagβ is defined as the slope of the Sensor’s response vs. Time curve. So, this can be concluded that the application of the indicated concrete-CNTs sensors for piezoresistive applications is feasible and the sensors can appraise the load with of high-goodness of fit (R2adj.> 0.99). In addition, to study the response of the concrete-CNTs sensor under the traffic loading, fatigue experiments were run. An alternative data processing log(G)-log(N) was applied instead of traditional S-log(N) fatigue graphs (Goodman curves), based on the electrical sensor response with a linear regression approach and the outcomes were verified by statistical tests. In this research, the concept of G has been defined for the first time as the slope of a sensor’s response that reflects the destruction created in a pavement because of one pass of vehicle load. Based on these findings, two various types of remaining life models for Portland cement concrete pavements were proposed

Investigating the micro/macro-texture performance of roller-compacted concrete pavement under simulated traffic abrasion

Since the roller-compacted concrete pavement (RCCP) is almost smooth due to roller vi-brations in the construction process, the lack of macro-texture prevents it from being used as a final surface. This study has made efforts to improve the RCCP by proposing different scenarios to cre-ate new micro-/macro-texture surfaces and investigate their durability and skid resistance under traffic abrasion conditions. To prepare the micro-texture, eight RCCP specimens were cast using various 50–50% mixing proportions, and each of them alone in the form of siliceous and calcareous fine aggregates (natural and manufactured). For the macro-texture, each specimen was textured using such methods as seeding (three cases), stamping (two cases), and brooming (two cases). Since the durable texture should withstand the abrasive traffic flow, the RCCP-surface abrasion resistance was measured by the simulation method proposed in ASTM C944, and their skid resistance was evaluated by measuring the British pendulum test according to ASTM E303 before and after abrasion. The results showed that abrasion resistance of RCCP samples to changes in mixing design and skid resistance to changes in macro-texture have significant changes. In addi-tion, different siliceous-calcareous sand combinations not only made the concrete mix more eco-nomical but also improved its performance in case of abrasion and skid resistance. The more was the manufactured sand proportion, the higher the fracture rate was and, hence, the abrasion re-sistance. Different macro-textures created on RCCP specimens generally showed acceptable skid resistance. In this regard, stamping had the highest mean texture depth (MTD) as well as BPN, and seeding had the lowest

A Novel Life Prediction Model Based on Monitoring Electrical Properties of Self-Sensing Cement-Based Materials

Assessing the damage level in concrete infrastructures over time is a critical issue to plan their timely maintenance with proper actions. Self-sensing concretes offer new opportunities for damage assessment by monitoring their electrical properties and relating their variations to damage levels. In this research, fatigue tests were conducted to study the response of a self-sensing concrete under high-cycle dynamic loading. The concept of G-value was defined as the slope of the voltage response baseline of the self-sensing concrete over time that reflects the damage created under the fatigue-loading test. Based on this definition, log (G)–log (N) curves were obtained using a linear regression approach, with N representing the number of cycles during the fatigue tests. While traditional fatigue curves S-log (N) are used to estimate the remaining life under fatigue loading, log (G)–log (N) diagrams can be used to determine the damage level based on the voltage response of the self-sensing concrete as a function of the loading history. This finding can be useful for the estimation of the lifetime and remaining life of self-sensing concrete structures and infrastructure, eventually helping to optimize the related maintenance operations

Experimental evaluation of tensile performance of aluminate cement composite reinforced with weft knitted fabrics as a function of curing temperature

Cement composites (CC) are among the composites most widely used in the construction industry, such as a durable waterproof and fire-resistant concrete layer, slope protection, and application in retaining wall structures. The use of 3D fabric embedded in the cement media can improve the mechanical properties of the composites. The use of calcium aluminate cement (CAC) can accelerate the production process of the CC and further contribute to improving the mechanical properties of the cement media. The purpose of this study is to promote the use of these cementitious composites by deepening the knowledge of their tensile properties and investigating the factors that may affect them. Therefore, 270 specimens (three types of stitch structure, two directions of the fabric, three water temperature values, five curing ages, with three repetitions) were made, and the tensile properties, absorbed energy, and the inversion effects were evaluated. The results showed that the curing conditions of the reinforced cementitious composite in water with temperature values of 7, 23, and 50 °C affect the tensile behavior. The tensile strength of the CCs cured in water with a temperature of 23 °C had the highest tensile strength, while 7 and 50 °C produced a lower tensile strength. The inversion effect has been observed in CC at 23 °C between 7 and 28 days, while this effect has not occurred in other curing temperature values. By examining three commercial types of stitches in fabrics and the performance of the reinforced cementitious composites in the warp direction, it was found that the structure of the “Tuck Stitch” has higher tensile strength and absorbed energy compared to “Knit stitch” and “Miss Stitch”. The tensile strength and fracture energy of the CC reinforced with “Tuck Stitch” fabric in the warp direction, by curing in 23 °C water for 7 days, were found to be 2.81 MPa and 1.65 × 103 KJ/m3, respectively. These results may be helpful in selecting the design and curing parameters for the purposes of maximizing the tensile properties of textile CAC composites

Correlating spiritual and emotional intelligence with academic performance among Pakistani students

Continuous learning works like a blood for organization and individuals to proceed and succeed. Underdeveloped countries need to address their academic issues. Academic prosperity is linked to economy and technology disruptions so it’s an important element to bring underdeveloped countries up to the mark to thrive and survive in this technical era. Academic prosperity depends upon student's enthusiastic attitude and their emotional and spiritual intelligences. This study was conducted in learning organizations to see the impact of emotional and spiritual intelligences on academic performance. Population of the study is the academic institutes of Pakistan. Data were collected using cross-sectional questionnaire-based survey from 113 students in Pakistan. The findings provide positive and significant correlations among the types of intelligences and academic performance. Data was analyzed using SPSS and the results were verified using statistical methods like correlation, regression, ANNOVA, Cronbach alpha and means. This study highlights the role of emotional intelligence and spiritual intelligence on academic performance and found out that it has the most demanding and significant effect on the academic performance, therefore it needs better integration in academic practices, routine and culture

Determining relationship between strategic human resource management practices and organizational commitment

Due to high involvement of human resource management (HRM), it has been a challenge for the organization to manage the external turbulence like war or government policy changes. This makes the HRM department play a crucial role to manage their employees together with the welfare of the organization. The main purpose of the article is to investigate the relationship between strategic HRM (SHRM) practices and organizational commitment (OC). Hypothesis was developed considering seven key SHRM practices and OC and subsequently testing based on data from 52 oil and gas companies in Libya. The findings using structural equation modeling revealed that employees are more committed to the organization when they get best SHRM. Internal career ladders on job training and pay for performance were the key SHRM practices identified that influence employee’s commitment toward the organization. Further, it was shown that the employees are more concerned of their job security and dynamic working environment. Employees with the help of organizational support will be able to contribute to enhance OC

Influencia del coeficiente estructural de una base reciclada con cemento sobre la deformación permanente en la subrasante – una aproximación con el método Sudrafricano

Trabajo de investigaciónEn la investigación se diseñaron pavimentos con una base reciclada con cemento, variando el módulo resiliente de la subrasante y el espesor de la sub-base granular, en cada caso. Para cada uno de los diseños se determinó la respuesta estructural (esfuerzo y deformación en la subrasante) a través de un software y con los resultados obtenidos se determinó la relación entre la deformación permanente en la subrasante y el número de ejes equivalentes correspondientes.1. INTRODUCCIÓN 2. PLANTEAMIENTO DEL PROBLEMA 3. OBJETIVOS 4. MARCO TEÓRICO 5. ESTADO DEL ARTE 6. PREGUNTA DE INVESTIGACIÓN 7. ALCANCES Y LIMITACIONES 8. METODOLOGÍA 9. CÁLCULOS Y RESULTADOS 10. ANÁLISIS DE RESULTADOS 11. CONCLUSIONES Y RECOMENDACIONES 12. BIBLIOGRAFÍAPregradoIngeniero Civi

Histopathologic investigation of the protective effects of omega-3 fatty acids against boric acid-induced injury in kidney and testis tissue

Objective: In this study, it was aimed to evaluate the effects of boric acid on rat kidney and testis tissues histopathologically. Secondly, the protective effects of omega-3 fatty acid against boric acid-induced renal and testicular toxicity were investigated. Methods: 32 wistar albino rats were divided into 4 groups as follows: Control, Omega-3 (400 mg/kg/day for 10 days), Boric acid (375 mg/kg/day for 10 days) and Boric acid+omega-3 (both drugs same dosage for same day). Kidney and testis tissues were evaluated using a scoring system based on the extent of certain histopathological changes. Results: In histopathological examination, boric acid caused significant degeneration in both testis and kidney tissues. Most evident findings were glomerular shrinkage and necrosis, hemorrhage and tubular cell degeneration in kidneys, and exfoliation of seminiferous tubule cells, detachement of epithelium from basement membrane, decreased cellularity and degeneration in epithelial cells in testis tissues. Omega-3 administration significantly attenuated these changes. Conclusion: To our literature search, this is the first study reporting protective effects of omega-3 fatty acid against boric-acid-induced testicular and renal injury

Sternal abscess overlying giant aortic pseudoaneurysm developed after Bentall procedure Bentall prosedürü sonrası gelişmiş dev aortik pseudoanevrizma üzerine oturmuş sternal apse Olgu Sunumu

Abstract Aortic pseudoaneurysms are one of the most important complications to be encountered in cardiac surgery. Recently, the aortic pseudoaneurysms have been diagnosed by contrast enhanced computerized tomography. It has high specificity and sensitivity rates. Late postoperative sternal abscesses are rarely seen after open heart surgery. Thorax computerized tomography scan revealed abscess extending from subcutaneous tissue to the medullar component of sternum, overlying retrosternal giant aortic pseudoaneurysms. This article presents the case of a patient, who had undergone Bentall procedure three years ago due to type I aortic dissection and later presented in our cardiovascular surgery department with a sternal mass. Pam Med J 2013;6(1):33-36 Key words: Abscess; sternal wound infection; aortic pseudoaneurysm Özet Aortic pseudoanevrizmalar kalp cerrahisinde karşılaşılabilecek en önemli komplikasyonlardan biridir. Son zamanlarda aortic pseudoanevrizmalara kontrastlı bilgisayarlı tomografi ile tanı konmaktadır. Bu test oldukça yüksek özgüllük ve hassasiyet değerlerine sahiptir. Geç dönem sternal apseler açık kalp cerrahisinden sonra nadiren gözlenmektedirler. Bilgisayarlı toraks tomografisinde subkutanöz dokudan başlayıp sternum medullasına kadar uzanan absenin aortik retrosternal dev bir pseudoanevrizma üzerine oturduğu saptandı. Bu makalede; üç yıl önce tip I aortic diseksiyon nedeni ile Bentall ameliyatı olan ve daha sonra sternal kitle yakınmasıyla kalp damar cerrahisi kliniğimize müracaat eden hasta sunulmaktadır. Tıp Derg 2013;6(1):33-36 Pa

Comparative evaluation of IS6110 PCR via conventional methods in rapid diagnosis of new and previously treated cases of extrapulmonary tuberculosis

ÖZET Yeni ve önceden tedavi edilmiş ekstrapulmoner tüberkülozlu hastaların hızlı tanısında IS6110 ile konvansiyonel yöntemlerin karşılaştırılmalı değerlendirilmesi Gelişmekte olan ülkelerde ekstrapulmoner tüberküloz (EPTB) tanısı önemli bir problemdir. EPTB'de, az sayıda basil içerme özelliği, yetersiz miktarda örnek gibi birçok sorun bulunmaktadır. Bütün bu kısıtlamalar, konvansiyonel bakteriyolojik tekniklerin EPTB tanısına düşük katkısına neden olmaktadır. Nükleik asit amplifikasyon yöntemleri, mikobakteriyel DNA'nın saptanması amacıyla geliştirilen hızlı ve duyarlı tekniklerdir. Mycobacterium tuberculosis complex'in spesifik genomunda yer alan "insertion sequence" IS6110'a ait 123bp'nin DNA fragmanı, EPTB'nin hızlı tanısı amacıyla polimeraz zincir reaksiyonu (PCR) ile çoğaltıldı. Bu çalışmada, yeni ve önceden tedavi edilmiş EPTB'li hastaların hızlı tanısında IS6110 PCR ile konvansiyonel yöntemler karşılaştırıldı. EPTB şüpheli hastalardan 450 örnek toplandı ve Mycobacteria için Zeihl Neelson (ZN) boyama ve M. tuberculosis için BACTEC kültürü yapıldı. Bütün örnekler ayrıca, M. tuberculosis complex'in insertion element IS6110'un 123bp fragmanını hedefleyen primerlerle PCR amplifikasyonu ile IS6110 için çalışıldı. Testler arasında duyarlılık bakımından anlamlı fark saptandı. Dört yüz elli örnek . Bununla birlikte, testler arasında spesifisite bakımından anlamlı fark yoktu (p> 0.05). IS6110 PCR'nin hem yeni hem de önceden tedavi edilmiş hastalarda, yayma mikroskopi ve BACTEC kültüründen daha duyarlı olduğunu bulduk. IS6110 PCR, yeni ve önceden tedavi edilmiş EPTB'li hastaların tanısında kullanışlı olabilir. Şüpheli EPTB'li hastaların tedavi kararında fayda sağlayabilir. Anahtar Kelimeler: Tüberküloz, ekstrapulmoner tüberküloz, polimeraz zincir reaksiyonu, IS6110. Yazışma Adresi (Address for Correspondence): Dr. Surya KANT, Chhatrapati Shahu Ji Maharaj Medical University UP (Erstwhile King George Medical College), LUCKNOW -INDIA e-mail: [email protected] Tuberculosis (TB) continues to be a major global public health problem. Incidence of extrapulmonary tuberculosis (EPTB) is on increasing worldwide as well as in India (1,2). EPTB compromises 20% of all TB cases in India (3). Diagnosis of EPTB in different clinical presentations has been always as challenge. Smear microscopy and culture lack of sensitivity in EPTB case and culture (solid and liquid media) also takes at least two to four weeks for grow of mycobacteria. A study has reported smear positive is around 10-37% of the patients and mycobacterial culture is positive in variable proportional 12-80% in different biological specimens (3). Studies from many laboratories around the global were using primers most commonly targeting the IS6110 insertion element (4-9). The detection of the IS6110 insertion element present in form of multiple copies to detect of Mycobacterium tuberculosis complex but not other mycobacterial species (9-11). Polymerase chain reaction (PCR) using IS6110 insertion sequences as the target, has potential to conquer limitation of conventional method and to established as rapid, sensitive technique for detecting DNA of M. tuberculosis in different clinical specimens from respiratory and non respiratory sites MATERIALS and METHODS Study Design The study was performed prospectively in a blinded manner. Clinical Specimens and Data Collection 2-5 mL of specimens was collected from 450 specimens, non-repeated specimens from suspected cases of extrapulmonary tuberculosis. The specimens were included as Lymph Node Aspirate and Cold Abscesses, Pleural fluid, C.S.F, Synovial Fluid, Ascetic Fluid, Urine, Gastric Aspirate, Pus, Bone Marrow, Wound and Pus swab and Others specimens (biopsies tissues). All specimens were kept in ice box and transported Mycobacteriology Laboratory, Department of Microbiology, Sanjay Gandhi Postgraduate Institute of Medical Sciences, Lucknow, India for smear examination by ZN Staining, BACTEC Culture and PCR test. All patients were signed with due informed consent of the patients from indoor and outward wards of Department of Pulmonary Medicine, Chhatrapati Shahuji Maharaj Medical University, Lucknow, India and Mycobacteriology Laboratory, Department of Microbiology, Sanjay Gandhi Postgraduate Institute of Medical Sciences, Lucknow, India during Jan 2009 to Dec 2010. The clinical history regarding, present and past history of antitubercular treatment (ATT); family history of tuberculosis and any other associated disease were taken in prescribed Performa. Microbiological Analysis of Extra Pulmonary Specimens Specimens was divided in to two part one part was kept at -20 for PCR till processing and another part was processed for mycobacterial smear preparation and BACTEC culture. Smears were stained with Ziehl Neelsen (ZN) method and examined for acid-fast bacilli (AFB) (21). BACTEC vials were incubated and interpreted as per Becton Dickinson (BD, Sparks, MD, USA) manual instructions (22). NAP (p-nitro-α-acetylamino-β-hydroxy propiophenone) (Becton Dickinson, Sparks, MD, USA), identification was done to differentiate M. tuberculosis form non tuberculous mycobacteria (22). A decrease or unchanged growth index (GI) in nap vial indicated presence of M. tuberculosis complex (MTBC), while an increase in GI indicated the presence of Mycobacterium other than tuberculosis (MOTT). Standard H 37 Rv strain of M. tuberculosis complex was used as positive control. Extraction of DNA Extraction of DNA was done by the CTAB (cetyl-trimethyl-ammonium bromide) -phenol chloroform extraction method (23). Specimens were centrifuged at 10.000 rpm for 10 min. The supernatant was discarded and the pellet suspended in 567 µL of TE (Tris EDTA, pH 7.4) buffer, 30 µL 10% SDS (sodium dodecyl sulfate) and 3 µL proteinase K (20 mg/mL), mixed and incubated at 37°C for 1 hour. After incubation, 100 µL of 5 M NaCl and 80 µL of high-salt CTAB buffer (containing 4 M NaCl, 1.8% CTAB was added and mixed followed by incubation at 65°C for 10 min. An approximate equal volume (0.7-0.8 µL) of chloroform-isoamyl alcohol (24.1) was added, mixed thoroughly and centrifuged for 4-5 min in a microcentrifuge at 12.000 rpm. The aqueous viscous supernatant was carefully decanted and transferred to a new tube. An equal volume of phenol: chloroform-isoamyl alcohol (1:1) was added followed by a 5 min spin at 12.000 rpm. The supernatant was separated and then mixed with 0.6 volume of isopropanol to get a precipitate. The precipitated nucleic acids were washed with 75% ethanol, dried and re-suspended in 100 µL of TE buffer. Primer and IS6110 PCR The amplification reaction was performed in a final volume of 20 µL. the reaction mixture contained 10 µL Pyrostart Fast PCR Master Mix 2X (dNTP, Taq polymerase with Mgcl 2 , Fermentas, India), 1 µL (10 pmole) of each primer, 3 µL water (nuclease free) and 5 µL of extracted DNA. The oligonucleotide primers used were IS1 and IS2, are: 5'-CCT GCG AGC GTA GGC GTC GG3' and 5' CTC GTC CAG CGC CGC TTC GG 3' respectively (SBS Gentech Co. Ltd) (24). These primers amplified a target fragment at 123 base pairs (bp) from the insertion, M. tuberculosis sequence element IS6110. The PCR amplification was done in thermal cycler (MJ Research, PTC-100, GMI, Inc, USA), which involved 40 cycles of denaturation at 94°C for 2 minute, annealing of primers at 68°C for 2 minute, and primer extension at 72°C for 1 minute. The amplified products were separated on 2% agarose gels, visualized on a UV-light transilluminator (Bangalore Genei, Bangalore, India). The presence of 123bp fragment indicate as positive test as M. tuberculosis complex. The positive controls included the DNA of H37Rv strain. Negative control included PCR grade water Statistical Analysis Data were analyzed using SPSS 15.0 (Statistical Package for the Social Sciences, Chicago, IL, USA) for Maurya AK, Kant S, Nag VL, Kushwaha RAS, Kumar M, Dhole TN. 215 Tüberküloz ve Toraks Dergisi 2011; 59(3): 213-220 Windows. The significance of difference was taken as significance value (p< 0.05).Sensitivity was calculated as [Tp/(Tp + Fn)] x 100; specificity was calculated as [Tn/(Tn + Fp)] x 100; Tp = total number of positives; Tn = total number of negatives; Fp = total number of false positive, Fn = total number of false negative; respectively. RESULTS Specimen's Characterization of Extrapulmonary Tuberculosis Cases During the two year study period, 470 clinical specimens were strong clinical suspicion of extrapulmonary tuberculosis were subjected from tertiary care hospitals and all mention test were performed. Out of these, 20 specimens found to be contaminated in BACTEC culture. 450 specimens of results were used in the study. Out of 450 specimens, 153 (34%) lymph node aspirate and cold abscesses, 58 (12.8%) pleural fluid, 44 (9.7%) cerebrum spinal fluid (CSF), 48 (10.7%) urine, 31(6.8%) ascetic fluid, 26 (5.8%) pus, 22 (4.9%) wound and pus swab, 16 (3.5%) gastric aspirate, 10 (2.2%) bone marrow, 10 (2.2%) synovial fluid and 30 (6.7%) others specimens (biopsies tissues). Out of 450 patients, 320 (71.1%) patients were males and 130 (28.9%) females. The mean age of all patients was 39.8 ± 16.1 years. Patients 25-44 years of age accounted for 45% of the total cases. Out of 450 cases, 328 (72.8%) were new cases and 122 (22.2%) were previously treated cases of EPTB. Detection Rate of M. tuberculosis by IS6110 PCR, BACTEC Culture and ZN Smear Microscopy According to New Cases and Previously Treated Cases All specimens were colleted from suspected case of extra pulmonary tuberculosis were found to be AFB positive were 60 (13.4%). On the basis of cases, we found that sensitivity of AFB staining on EPTB were 37 (11.2%) in new cases and 23 (18.8%) in previously treated cases. The sensitivity of AFB staining was higher in comparison to previously treated cases. Overall detection rate of M. tuberculosis by AFB Staining was 60 (13.4%). The detection of M. tuberculosis by BACTEC culture was 202 (45%). Results of BACTEC culture according to cases, 151 (46.03%) were in new cases and 51 (41.8%) were in previously treated cases. We found that sensitivity of BACTEC culture was higher in new cases. All culture isolates obtained were confirmed as mycobacteria with biochemical tests mentioned. Using IS 6110 PCR, 283 (61.8%) were positive for IS6110 PCR for M. tuberculosis. 203 (61.8%) were positive in new cases and 80 (65.5%) were positive in previously treated cases. We found that sensitivity of IS6110 PCR was higher in previously treated cases. Overall comparison of tests, IS6110 PCR was found to have much higComparative evaluation of IS6110 PCR via conventional methods in rapid diagnosis of new and previously treated cases of extrapulmonary tuberculosis 216 Tüberküloz ve Toraks Dergisi 2011; 59(3): 213-220 Comparison of Sensitivity of IS6110 PCR Test Via Others Conventional Tests According to New Cases and Previously Treated Cases IS6110 PCR test was found to be much more sensitive than ZN staining and BACTEC culture results individually as well as in combination are shown in 217 Tüberküloz ve Toraks Dergisi 2011; 59(3): 213-220 DISCUSSION Tuberculosis (TB) is a major public health dilemma in India. India is the highest TB burden country accounting for one fifth of the global incidence. Global annual incidence estimate is 9.4 million cases out of which it is estimated that 1.98 million cases are from India (26). In India, EPTB comprises 20% of all TB cases. Its prevalence in the country varies between 8.3-13.1% in different districts according to cohort analysis by Central TB Division, Ministry of Health and Family Welfare in 2002 (27,28). The diagnosis of extrapulmonary tuberculosis is till now challenging for diagnostic routine laborites. Numeric reasons are showing that, lack of adequate specimens amounts or volumes; distribute of the specimens for different diagnostic tests (histology/cytology, biochemical analysis, microbiology, and PCR), non-uniform distribution of microorganisms; paucibacillary nature of the specimens; presence of inhibitors that undermine the performance of nucleic acid amplification-based techniques; and the lack of an efficient sample processing technique universally applicable on all types of extrapulmonary samples (29). The poor performance of conventional M. tuberculosis detection techniques, based on microscopic examination of Ziehl-Neelsen stained and culture of M. tuberculosis (LJ Medium and BACTEC Radiometric culture) are still in widespread use for diagnostic purposes, still though they fail to provide the required sensitivity and specificity. The PCR test would be particularly useful in the diagnosis of EPTB where conventional microbiological techniques for M. tuberculosis are showing poor performance of sensitivity. The specificity, sensitivity and speed of PCR test in diagnosis of M. tuberculosis infection shown in this study should encourage the use of this method in routine diagnosis of EPTB. Previously studies shown the success of microscopy is highly variable from 22% to 96% and most authors rate it at round 60% (30-32). Our results shown that sensitivity of smear microscopy was 13.7% and specificity was 100%. The sensitivity of microscopy depends on the clinical presentation and more than 10.000 bacilli per milliliter are necessary for secure microscopic positivity (33). Our studies shown that conventional bacteriological technique were positive in 202 (45%) specimens, where as IS6110 PCR showed that 283 (63%) specimens were positive for M. tuberculosis. The difference was found that to be statistical significant (p< 0.05). Several studies have been reported on PCR to detect M. tuberculosis (34-39). The detection of the IS6110 insertion element present in multiple copies to detect M. tuberculosis complex, but not other mycobacterial species 218 Tüberküloz ve Toraks Dergisi 2011; 59(3): 213-220 tion and PCR results were positive but BACTEC culture was negative; these could be the presence of nonviable mycobacteria in the sample as patients were receiving antitubercular treatment. IS6110 PCR test is higher sensitivity than microscopy and the culture and could help in therapeutic decision for patients with clinical suspicion of EPTB. CONCLUSION IS6110 PCR test for DNA specific M. tuberculosis may be hopes of a rapid and accurate diagnostic test for EPTB and it will help where conventional diagnosis fails and provisional diagnosis of tuberculosis is made on the basis of clinical presentation and histology/cytology examination without evidence of AFB. IS6110 PCR may be great potential to improve the clinician vision for the early diagnosis, treatment and prevention of EPTB. ACKNOWLEDGEMEN