Bacillus amyloliquefaciens AD 20 and Bacillus altitudinis AD 14 Isolated from a Dye Pond Decolorize Synthetic Textile Reactive Dyes

A screen of textile effluents, receiving waterbodies, and waste sites near a textile factory was undertaken to isolate new bacteria strains capable of dye degradation. Out of the 45 isolates, two dye decolorizers, Bacillus altitudinis AD14 and B. amyloliquefaciens AD20, obtained from the sediment samples were identified by cultivation and 16S rRNA gene sequencing. Decolorization testing was performed under static aerobic conditions in the laboratory. The two Bacillus species showed dye decolorization capabilities on media containing each of these four commercial textile azo dyes- Reactive Blue 4 Red (RBFR), Cibacron Brilliant Orange 4 Red (COFR), Cibacron Brilliant Yellow 6 Percent Green (CYPGS), and Turquoise Cibacron Green (TCG). At the end of a ten-day incubation period, B. amyloliquefaciens AD20 was more efficient in dye reduction than B. altitudinis AD14 on CYPGS and COFR at a magnitude of four-fold and two-fold, respectively, while B. altitudinis AD14 only outperformed it in the TCG dye media. The isolates performed best on medium containing RBFR; the principal dye used by the textile factory. Genome annotation revealed the absence of plasmids and the presence of putative genes associated with dye decolorization, such as laccase and azoreductases

Bacillus amyloliquefaciens AD 20 and Bacillus altitudinis AD14 Isolated from a Dye Pond Decolorize Synthetic Textile Reactive Dyes

A screen of textile effluents, receiving waterbodies, and waste sites near a textile factory was undertaken to isolate new bacteria strains capable of dye degradation. Out of the 45 isolates, two dye decolorizers, Bacillus altitudinis AD14 and B. amyloliquefaciens AD20, obtained from the sediment samples were identified by cultivation and 16S rRNA gene sequencing. Decolorization testing was performed under static aerobic conditions in the laboratory. The two Bacillus species showed dye decolorization capabilities on media containing each of these four commercial textile azo dyes- Reactive Blue 4 Red (RBFR), Cibacron Brilliant Orange 4 Red (COFR), Cibacron Brilliant Yellow 6 Percent Green (CYPGS), and Turquoise Cibacron Green (TCG). At the end of a ten-day incubation period, B. amyloliquefaciens AD20 was more efficient in dye reduction than B. altitudinis AD14 on CYPGS and COFR at a magnitude of four-fold and two-fold, respectively, while B. altitudinis AD14 only outperformed it in the TCG dye media. The isolates performed best on medium containing RBFR; the principal dye used by the textile factory. Genome annotation revealed the absence of plasmids and the presence of putative genes associated with dye decolorization, such as laccase and azoreductase

Executive cash compensation and tax aggressiveness of Chinese firms

We examine the influence of corporate compensation policies on firms’ tax aggressiveness in an emerging market where executive compensation is primarily in cash form. Based on a hand-collected dataset of 958 firm-year observations of Chinese listed firms for the 2006-2012 period, we find that firms paying higher executive cash compensation are associated with lower tax aggressiveness. This relationship also holds for the excess cash compensation measures which control for executive shareholding, firm profitability, size, growth opportunity, and board independence. We further document that mutual funds ownership pressure firms paying higher compensation to reduce their tax aggressiveness, suggesting adverse selection by mutual funds on firms exhibiting risky tax avoidance activities. High leverage offsets the negative link between cash compensation and tax aggressiveness, indicating a complementary effect between debt and tax avoidance, and, hence, suggesting that creditor monitoring is weak. These results are robust to the system-GMM estimation, which simultaneously account for the endogeneity of executive compensation, tax aggressiveness, ownership and control, leverage, and corporate governance. Our findings on Chinese firms have important policy implications for developing countries around the world with concentrated ownership structure, weak institutional environment, widespread corruption, ineffective rule of law, and ongoing significant social and political transformation

Understanding Growth and Malnutrition in Baka Pygmy Children

We determined stunting, wasting, and obesity frequencies in a total 1092 2-to-12 year old Baka Pygmy children from anthropometric and health data gathered in 34 villages in the Djoum-Mintom region in southeastern Cameroon in four health campaigns in 2010 and 2017–9. We compare these to the WHO Child Growth Standards, Amazonian Tsiname growth references for inter-population comparisons and the study population itself. Population-specific growth charts were constructed using GAMLSS modelling. Our results show that Baka children have one of the highest global rates of stunting relative to the WHO child growth standard with 57.8% for 2-to-12 year olds and 64% and 73% for 2-to-4 year old girls and boys, respectively. Frequencies of wasting, overweight, and low BMI were low at 3.4%, 4.6% and 4.3%, respectively, for 2-to-12 year olds. Underweight was at 25.5%, in the upper range for sub-Saharan Africa. Edemas indicated rare severe malnutrition (0.3%). Uncertainties in age estimation had dramatic effects on the reliability of estimated individual z-scores but distributions of z-scores were robust at a population level. In the context of the recent evidence for genetic adaptation of the Pygmies’ small stature to the tropical forest environment we argue that WHO child standards for weight and BMI are applicable. However, standards for height are clearly not adequate for Pygmy people. To achieve UN Sustainable Development Goals, we recommend that Pygmy specific growth standards are developed for the various, genetically differing Pygmy tribes

Instructional Models for Course-Based Research Experience (CRE) Teaching

The course-based research experience (CRE) with its documented educational benefits is increasingly being implemented in science, technology, engineering, and mathematics education. This article reports on a study that was done over a period of 3 years to explicate the instructional processes involved in teaching an undergraduate CRE. One hundred and two instructors from the established and large multi-institutional SEA-PHAGES program were surveyed for their understanding of the aims and practices of CRE teaching. This was followed by large-scale feedback sessions with the cohort of instructors at the annual SEA Faculty Meeting and subsequently with a small focus group of expert CRE instructors. Using a qualitative content analysis approach, the survey data were analyzed for the aims of inquiry instruction and pedagogical practices used to achieve these goals. The results characterize CRE inquiry teaching as involving three instructional models: 1) being a scientist and generating data; 2) teaching procedural knowledge; and 3) fostering project ownership. Each of these models is explicated and visualized in terms of the specific pedagogical practices and their relationships. The models present a complex picture of the ways in which CRE instruction is conducted on a daily basis and can inform instructors and institutions new to CRE teaching

Models of classroom assessment for course-based research experiences

Course-based research pedagogy involves positioning students as contributors to authentic research projects as part of an engaging educational experience that promotes their learning and persistence in science. To develop a model for assessing and grading students engaged in this type of learning experience, the assessment aims and practices of a community of experienced course-based research instructors were collected and analyzed. This approach defines four aims of course-based research assessment—(1) Assessing Laboratory Work and Scientific Thinking; (2) Evaluating Mastery of Concepts, Quantitative Thinking and Skills; (3) Appraising Forms of Scientific Communication; and (4) Metacognition of Learning—along with a set of practices for each aim. These aims and practices of assessment were then integrated with previously developed models of course-based research instruction to reveal an assessment program in which instructors provide extensive feedback to support productive student engagement in research while grading those aspects of research that are necessary for the student to succeed. Assessment conducted in this way delicately balances the need to facilitate students’ ongoing research with the requirement of a final grade without undercutting the important aims of a CRE education