NDT methods applicable to concrete bridges are reviewed. The methodology, advantages and disadvantages along with up to date research on NDT methods are presented. Different damage levels, having less dependence on inspector judgment, are suggested. Moreover, a flow chart based on damage level along with NDT methods and potential remedial measures are proposed for periodic health monitoring of structures. NDT methods are also suggested to address specific problems related to structures. Finally, the relation between some of the well-known NDT methods and most common problems encountered by the field engineers is proposed. Hence, the importance of structural health monitoring is highlighted. Original language EnglishPages (from-to) 58-86

We tested 240 patients with Plasmodium falciparum monoinfection for persistent parasite antigenemia after successful standardized antimalarial therapy by using the ICT Malaria Pf/Pv and OptiMAL-IT assays that detect the malaria antigens Plasmodium falciparum histidine-rich protein 2 (HRP2) and parasite lactate dehydrogenase (pLDH), respectively, as well as a panmalarial antigen (PMA). The patients were screened for antigenemia on days 0, 3, 7, and 14 of follow-up. On day 0, all 240 patients showed positive reactivity with both assays. Of the 229 cases with negative parasitemia on day 3, persistent antigenemia was observed in 207 (90.4%) of the cases: 188 (82.1%) for HRP2 antigen and 75 (32.8%) for PMA. There was a gradual decrease in antigenemia on follow-up to day 14; however, the drop in reactivity to PMA was less than that for HRP2 antigen. In contrast to HRP2 antigenemia, there was a significant decrease in pLDH antigenemia to 38.4% and to 14.8% (PMA) on day 3 (P < 0.03). The pLDH antigenemia level dropped further to 14.8% on day 7. There was no significant association of persistent antigenemia with gametocytemia. One case with gametocytemia was negative for both the antigens. In conclusion, the OptiMAL-IT assay is more sensitive than the ICT Malaria Pf/Pv test for monitoring therapeutic responses after antimalarial therapy since the LDH activity ceases when the malarial parasite dies.Clinical diagnosis of malaria still relies upon identification of malaria parasites in Giemsa-stained blood smears of the peripheral blood. Recently, rapid diagnostic tests for the detection of Plasmodium falciparum infection has been introduced to overcome the problem of time constraints and low sensitivity in diagnosing malaria infections with a low level of parasitemia by microscopy. These rapid diagnostic tests are the immunochromatographic tests (ICT) based on the detection of antigen(s) released from the parasitized red blood cells. In the case of P. falciparum infection, these new rapid methods are based on detection of the histidine-rich protein 2 (HRP2; e.g., the ICT Malaria Pf, ParaSight-F, and ICT Malaria Pf/Pv tests) (1-6, 11, 20) or parasite lactate dehydrogenase (pLDH; e.g., OptiMAL-IT) (7-9, 11, 18-20). The sensitivities and specificities of each of these tests have been assessed in a range of clinical situations (1,2,5,7,11,19), although the overall sensitivity and specificity of all of these assays to detect P. falciparum infection is high (Ͼ90%). However, the sensitivity of these assays decreases to Ͻ70% in parasitemia Ͻ50/l. Further, these assays may remain positive due to persistence of P. falciparum HRP2 antigenemia after antimalarial therapy. This may result in a false-positive (FP) diagnosis of infection and thus may reduce the usefulness of the test in predicting treatment failure (4,11,12,19). FP reactions have been reported in individuals with a history of recent fever and antimalarial treatment due to persistent circulation of HRP2 for up to 2 weeks after clearance of parasites or in patients who had...

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One of the methods for strengthening square concrete columns is shape modification. The method involves modification of the column cross section from square to circular by bonding concrete segments and then wrapping the column with fiber reinforced polymer (FRP). This paper investigates experimentally the applicability of the shape modification (circularization) for square hollow reinforced concrete (RC) specimens under different loading conditions. Five groups of four hollow RC specimens made from normal strength concrete were cast and tested. The specimens in the first group were RC hollow specimens, which served as reference specimens. The corners of the specimens in the second group were rounded to 20 mm and wrapped with two layers of carbon FRP (CFRP). The specimens in the third group were circularized and wrapped with two layers of CFRP. The specimens in the fourth group were bonded with one CFRP strap longitudinally on each side and then circularized and wrapped with two layers of CFRP. The specimens in the fifth group were wrapped with one layer of CFRP and then circularized and wrapped with two layers of CFRP. The results show that circularization increased the strength and ductility of the hollow specimen. Transverse wrapping with CFRP mainly improved the performance of the specimens under concentric axial loadings, while the longitudinal CFRP straps mainly improved the performance of the specimens under eccentric axial loading.