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Asymptomatic transmission was found to be the Achilles' heel of the symptom-based screening strategy, necessitating the implementation of mass testing to efficiently contain the transmission of COVID-19 pandemic. However, the global shortage of molecular reagents and the low throughput of available realtime PCR facilities were major limiting factors.A novel semi-nested and heptaplex (7-plex) RT-PCR assay with melting analysis for detection of SARS-CoV-2 RNA has been established for either individual testing or 96-sample pooled testing. The complex melting spectrum collected from the heptaplex RT-PCR amplicons was interpreted with the support of an artificial intelligence algorithm for the detection of SARS-CoV-2 RNA. The analytical and clinical performance of the semi-nested RT-PCR assay was evaluated using RNAs synthesized in-vitro and those isolated from nasopharyngeal samples.The LOD of the assay for individual testing was estimated to be 7.2 copies/reaction. Clinical performance evaluation indicated a sensitivity of 100% (95% CI: 97.83-100) and a specificity of 99.87% (95% CI: 99.55-99.98). More importantly, the assay supports a breakthrough sample pooling method, which makes possible parallel screening of up to 96 samples in one real-time PCR well without loss of sensitivity. As a result, up to 8,820 individual pre-amplified samples could be screened for SARS-CoV-2 within each 96-well plate of realtime PCR using the pooled testing procedure.The novel semi-nested RT-PCR assay provides a solution for highly multiplex (7-plex) detection of SARS-CoV-2 and enables 96-sample pooled detection for increase of testing capacity. .

Development of molecular markers for growth trait in striped catfish (Pangasianodon hypophthalmus) is of importance to the aquaculture industry in the Mekong river delta. This study aims to analyze the genetic variation and the effects of the Insulin-like growth factor 1 (IGF1) and Insulin-like growth factor 1 receptor (IGF1R) genes on growth traits in striped catfish. We sequenced fragments of IGF1 and IFG1R genes from 10 individuals of fast-growing fish and 10 individuals of slow-growing fish to discover single nucleotide polymorphisms (SNPs). Among the discovered SNPs, one SNP (13,680 A > T in intron 2) of IGF1 gene, three SNPs (13,357 T > C, 15392 T > A in intron 1 and 83,894 A > G in intron 15) in IGF1R gene were filtered and further validated by individual genotyping in 70 fast-growing fish and 70 slow-growing fish using the multiplex SNaPshot method (single base extension method). Our analyses showed that two SNPs (IGF1:13680 A > T and IGF1R:13357 T > C) were significantly associated with the growth trait (p T and genotype TT of IGF1R:13357 T > C led to the positive cumulative effect on the growth (p

Building on new institutional theory, this paper develops an analytical framework for analyzing constraints to the institutionalization of strategic environmental assessment (SEA) at four different institutional levels. The framework is tested in an empirical analysis of the environmental assessment system in Vietnam, which is a frontrunner among developing countries regarding the introduction and use of SEA. Building on interviews with Vietnamese and international experts, as well as an extensive literature review, we identify institutional constraints which challenge the effective use of SEA in Vietnam. We conclude that commonly identified constraints, such as inadequate training, technical guidelines, baseline data and financial resources, are strongly linked to constraints at higher institutional levels, such as incentives to not share information between ministries and severe restrictions on access to information and public participation. Without a thorough understanding of these institutional constraints, there is a risk that attempts to improve the use of SEA are misdirected. Thus, a careful institutional analysis should guide efforts to introduce and improve the use of SEA in Vietnam and other developing countries. The analytical framework for analyzing constraints to institutionalization of SEA presented in this paper represents a systematic effort in this direction.

AIM: To survey the detailed analyses for Helicobacter pylori (H. pylori) infection and gastric mucosal status in Myanmar. METHODS: A total of 252 volunteers with dyspeptic symptoms (155 female and 97 male; mean age of 43.6 ± 14.2 years) was participated in Yangon and Mandalay. The status of H. pylori infection was determined based on 5 different tests including rapid urease test, culture, histology, immunohistochemistry and serology. Histological scores were evaluated according to the update Sydney system and the Operative Link for Gastritis Assessment system. Pepsinogen (PG) I and PG II were measured using enzyme-linked immunosorbent assays. RESULTS: The overall prevalence of H. pylori infection was 48.0%. There was no relationship between age and infection rate. Even in young group (less than 29 years old), the H. pylori infection rate was relatively high (41.9%). The prevalence of H. pylori infection was significantly higher in Yangon than that of Mandalay. H. pylori infection was significantly associated with the presence of gastric mucosal atrophy. All 7 subjects with peptic ulcer were infected with H. pylori. Although H. pylori-positive subjects showed stronger gastritis than H. pylori-negative subjects, most cases had mild gastritis. CONCLUSION: We revealed the prevalence of H. pylori infection in patients with dyspeptic symptoms in Myanmar. The H. pylori infection was a risk factor for peptic ulcer and stronger gastritis.