Sharpness evaluation of microscopic detection image for micro parts

According to the characteristics of micro parts microscopic detection image, including the image texture is similar, the edge information is too little and the gray distribution Range is limited, based on the basic principles of algorithm, analyzes the traditional sharpness evaluation function. Aiming at the defect that the traditional sharpness evaluation function cannot have both high sensitivity and noise immunity, an algorithm based on local variance information entropy is proposed. The method uses the local variance to weight the self-information of each gray level, on the one hand, it makes up for the lack of spatial information of information entropy and avoids misjudgement of sharpness; on the other hand, it can increase the weights of clear region pixels when they participate in the calculation of information, while reducing the weights of background and noise region pixels, thereby improve the function sensitivity. The experimental results show that compared with the traditional sharpness evaluation function, the local variance information entropy function not only has high sensitivity, but also has better noise immunity and is suitable for actual auto-focusing systems.

The Microscopic Detection and Identification of Acanthamoeba Spp. In Water Samples Following Enrichment by in Vitro-Cultivation Under Two Distinct Temperature Conditions.

Acanthamoeba is a genus of free-living amoeba commonly found in environmental sources such as water, soil and air, and can infect humans. There is a significant challenge in the detection and identification of members of this genus in water samples. In order attempt to overcome this challenge, we investigated using in vitro culture, under distinct temperature conditions, to grow and enrich amoeba prior to detection and identification. Aliquots of 150 water samples, collected from Rabat (30 from each river, fountain, sea, public bath and tap water), were individually inoculated into standard culture medium non-nutritive agar and incubated for two weeks at 25 °C and 30 °C under otherwise standard conditions. PCR was used to confirm the presence of Acanthamoeba DNA in positive samples. The findings showed that Acanthamoeba grew more rapidly at 30 °C than 25 °C, allowing improved microscopic detection and identification at the former temperature. This investigation shows clearly that the diagnostic sensitivity of an in vitro based culture system is temperature-dependent.

Assessment of Microscopic detection of Malaria with Nested Polymerase Chain Reaction in War-torn Federally Administered Tribal Areas of Pakistan

Background: Diagnostic accuracy of malaria is critical for early treatment, control, and elimination of malaria, especially in war-affected malaria endemic areas. Microscopic detection of Plasmodium species has been the gold standard in remote malaria-endemic regions. However, the diagnostic accuracy is still questioned, especially in discriminating mixed and submicroscopic parasitic levels. This study was designed to evaluate the diagnostic performance of microscopic examination against nested PCR analysis in war-torn malaria-endemic Federally Administered Tribal Areas (FATA) of Pakistan. Methods: Venous blood samples were collected from symptomatic patients for microscopic examination and nested PCR analysis from January 2016 - December 2016 from five Agencies (Bajaur, Mohmand, Khyber, Orakzai and Kurram Agency) and four Frontier Regions (Peshawar, Kohat, Bannu, and Dera Ismail Khan Frontier Region) of FATA. Malaria-positive isolates were confirmed by nested PCR (targeting Plasmodium small subunit ribosomal ribonucleic acid (ssrRNA) genes) for speciation. Results: Among enrolled participants, 762 were found positive for malaria parasite on microscopic examination of the blood film. P. vivax was found in 623, P. falciparum in 132 and 7 were diagnosed with mixed infection (P. vivax and P. falciparum coinfection). Nested PCR detected Plasmodium infection in 679 samples (523 P. vivax, 121 P. falciparum, and 35 mixed infections). Compared with microscopy, the sensitivity of nested PCR was 98.94%, and specificity was 98.27%, while the sensitivity and specificity of slide microscopy 89.34% and 87.99% respectively. Conclusion: The conventional microscopy method has low sensitivity to detect mixed infection as compared to nested PCR. High sensitivity and specificity observed in nested PCR makes this molecular tool a useful technique for monitoring, controlling, and eliminating malaria-endemic regions.