Antimicrobial resistance is a major health problem, particularly in developing countries like Bangladesh, where there is a paucity of information on resistance patterns and prevalence of antimicrobial determinants. Therefore, the aims of this study were to investigate the prevalence of resistance, including multi-drug resistance (MDR), and the associated genetic determinants in Escherichia coli isolates from cloacal swabs of live broiler chickens in Bangladesh. Altogether, 400 cloacal swabs (200 from Rajshahi and 200 from Dhaka divisions) were randomly collected from individual chickens in 50 broiler farms. E. coli was isolated and identified using conventional bacteriological culture and biochemical methods. The isolates were further confirmed using genus-specific 16S rRNAtargeted polymerase chain reaction (PCR) primers. Antimicrobial susceptibilities and MDR of the isolates against nine different antimicrobial agents (ampicillin, erythromycin, tetracycline, gentamicin, ciprofloxacin, levofloxacin, trimethoprim-sulfamethoxazole, colistin sulphate, and streptomycin) were determined using the Kirby-Bauer disc diffusion method. Resistance determinants of E. coli to ampicillin (blaTEM), streptomycin (aadA1), erythromycin [ere(A)], trimethoprim (dfrA1), and tetracycline [tet(A), tet(B)] were screened using PCR. Our results showed that all swab samples were positive for E. coli. The isolates were uniformly resistant to ampicillin, tetracycline, streptomycin, ciprofloxacin, erythromycin, and trimethoprim-sulphamethoxazole. The isolates exhibited highest susceptibility to colistin sulphate (73.5%), followed by gentamicin (49%), and levofloxacin (17%). All isolates were resistant to three classes of antibiotics, 204 isolates (51%) were resistant to four classes, and 56 isolates (14%) were resistant to five. The highest prevalence of antimicrobial resistance gene was recorded for tetracycline (tet(A):95.25%; tet(B):95.25%) followed by ampicillin (blaTEM:91.25%), streptomycin (aadA1:88.25%), erythromycin (ere(A):84.75%), and trimethoprim (dfrA1:65.5%). In conclusion, surveillance for MDR bacteria in poultry is a critical piece of knowledge, which would be useful for optimizing empiric antimicrobial treatments and exploring alternative antimicrobial agents.

Antibiotic-resistant Escherichia coli (E. coli) are common in retail poultry products. In this study, we aimed to isolate and characterize multidrug resistant (MDR) E. coli in raw chicken meat samples collected from poultry shops in Sylhet division, Bangladesh, as well as to determine correlation between resistance phenotype and genotype. A total of 600 chicken meat swabs (divided equally between broiler and layer farms, n = 300 each) were collected and the isolates identified as E. coli (n = 381) were selected. Disc diffusion antimicrobial susceptibility assay showed resistance of these isolates to ampicillin, erythromycin, tetracycline, streptomycin, trimethoprim-sulfamethoxazole, chloramphenicol, and gentamicin. Polymerase chain reaction (PCR) identified several antibiotic resistance genes (ARGs) in our isolates. Among these ARGs, the prevalence of tetA (for tetracycline) was the highest (72.58%) in broiler chicken isolates, followed by sul1 (for sulfonamide; 44.16%), aadA1 (for streptomycin; 33.50%), ereA (for erythromycin; 27.41%), aac-3-IV (for gentamicin; 25.38%), and the two genes cmlA (24.87%) and catA1 (8.63%) for chloramphenicol. On the other hand, the respective prevalence in layer chicken isolates were 82.06%, 47.83%, 35.87%, 35.33%, 23.91%, 19.02%, and 5.43%. Furthermore, 49.23% of the isolates from broiler chicken were MDR, with the presence of multiple antibiotic resistance genes, including 3 (40.11%) and 4 (9.13%) genes. On the other hand, 51.09% of layer chicken E. coli isolates were MDR, with 3, 4 or 5 ARGs detected in 36.41%, 14.13%, and 0.54% of the isolates, respectively. We also found that 12.8% of broiler chicken E. coli isolates and 7.61% of layer chicken isolates carried genes coding for extended-spectrum SHV beta-lactamases. Lastly, we report the presence of the AmpC beta-lactamase producing gene (CITM) in 4.56% and 3.26% of broiler and layer chicken E. coli isolates, respectively. We found significant correlations between most of the antimicrobial resistant phenotypes and genotypes observed among the investigated E. coli isolates. Our findings highlight the need for the prudent use of antimicrobials in chickens to minimize the development of antibiotic-resistant bacterial strains.

Rice blast caused by Magnaporthe grisea is the major damaging disease in nearly all rice growing nations. Economically relevance with 60 percent of total population of world depending on rice as the main source of calories, may have destructive effects of the disease, however, this pathogen has developed into a pioneering model system for researching host-pathogen interactions. The disease outbreak depends on the weather and climatic conditions of the various regions. The disease's occurrence and symptoms vary from country to country. Susceptible cultivars cause huge rice production loss in yield. The principal cause of resistance breakdown in rice against rice blast disease is pathogenic variability. During sexual hybridization, pathogenic changes may provide evidence of pathogenic variation found at the asexual stage of the fungus. The virulent pathotypes cause severe disease incidence. Only through pathogenicity research the pathotypes can be determined using a collection of different rice varieties that are usually different carrying various resistance genes. Rice breeders now have a number of resistant genes however, most of the breeding programs emphasized upon monogenic resistance. Genetic heterogeneity of M. grisea should be taken into account when screening blast resistant rice genotypes through morphological analysis, pathogenicity and molecular characterization. Knowledge on the virulence of the rice blast and host resistant is essential for managing the disease. Cultivation of resistant varieties with chemical control is highly effective against blast pathogens.

Mathematical proving is an important ability to learn abstract algebra. Many students, however, found difficulties in solving problems involving mathematical proof. This research aims to describe the students' mathematical proving ability and to find out the difference of the ability among students in private universities with three different levels of accreditation-A, B, and C. We used descriptive and comparative methods to reach the goals by involving mathematics education department students from A, B, and C-accredited private universities as its subjects. We used a test and interview to collect the data. The data of the students' mathematical proving ability were then statistically described and then compared among the three subject categories using the Kruskal-Wallis test and U Mann Whitney post hoc test. The results suggest that the students' mathematical proving ability from the A, B, and C-accredited universities respectively were 77.14 (high category), 39.32 (low category), and 36.78 (low category). Furthermore, the comparison results suggest that the significant differences only happen between universities with A and B accreditation level, and between the ones with A and C accreditation. Based on these findings, the mathematical proving ability of the students from B and C-accredited universities still needs to be improved by making the students accustomed to exercising with proof problems, motivating them to learn, and providing them learning materials that are easy to understand.

Tulang ikan kambing-kambing salah satu limbah padat yang masih menjadi hasil samping yang belum dimanfaatkan. Tulang ikan kambing-kambing merupakan salah satu limbah padat yang sangat berpotensi sebagai salah satu sumber kalsium. Penelitian ini bertujuan untuk memanfaatkan tulang ikan kambing-kambing  menjadi produk yang bernilai ekonomis dan sumber kalsium. Penelitian ini menggunakan metode hidrolisis protein untuk mengetahui karakteristik bahan baku tulang ikan kambing-kambing dan proksimat (kadar air, kadar lemak, kadar abu), kalsium dan nilai FTIR tepung tulang ikan kambing-kambing  yang dihasilkan. Penelitian ini menggunakan ekstraksi basa NaOH dengan perbedaan konsentrasi yaitu 1N, 1,5N dan 2N. Nilai rendemen yang didapatkan adalah 7,55%, 12,94% dan 10,96%. Nilai kadar air yang didapatkan adalah 3,79%,  4,15% dan 3,87%. Nilai kadar lemak adalah 0,12%, 0,11% dan 0,10%. Nilai kadar abu yang didapatkan adalah 90,05 %, 88,76% dan 87,52%. Nilai kalsium yang didapatkan adalah 31,83 %, 35,75% dan 32,33%. Pengujian FTIR menunjukkan pada tepung tulang ikan kambing-kambing terdapat kalsium.Kata kunci: ekstraksi; kalsium; ikan kambing-kambing (Abalistes stellaris) Starry triggerfish bone is one of the solid waste, which is a by-product that has not been utilized. It has great potential as a source of calcium. This research aims to utilize starry triggerfish bone to be a valuable product and source of calcium. This research used the protein hydrolysis method to determine the characteristic of raw material and proximate of starry triggerfish bone (water, fat and ash content), calcium and FTIR values of starry triggerfish bone meal. This research uses NaOH base extraction with different concentrations of 1N, 5N and 2N. The yield value obtained were 7,55%, 12,4% and 10,96%. The values of water content obtained were 3,7%, 4,15% and 3,87%. The value of fat content were 0,12%, 0,11% and 0,10%. Ash content values obtained were 90,05%, 88,76% and 87,52%. Calcium values obtained were 31,83%, 35,75% and 32,33%. FTIR testing showed that the bone meal of starry triggerfish contained calcium.Keywords: extraction; calcium; starry triggerfish (Abalistes stellaris)