<Emphasis Type="Italic">Darshana</Emphasis> Jolts

The nature of matter, or body considered in general, consists not in its being something which is hard or heavy or coloured, or which affects the senses in any way, but simply in its being something which is extended in length, breadth and depth.     

Cloning and efficient expression of <Emphasis Type="Italic">Bacillus sp.</Emphasis> BH072 <Emphasis Type="Italic">tasA</Emphasis> gene in <Emphasis Type="Italic">Escherichia coli</Emphasis>

The Bacillus strain BH072 isolated from a honey sample showed strong antifungal activity against phytopathogen. Gene cloning test demonstrated that the strain had a tasA gene encoding an antifungal TasA protein. Although the wild strain simultaneously produced various antifungal substances, only the physicochemical property and antifungal activity of TasA protein were unclear due to the difficulty in extraction. In this study, tasA gene encoding the protein from Bacillus sp. BH072 was amplified by using the polymerase chain reaction (PCR) method and cloned into pET 28a (+) vector, and then expressed in host cells Escherichia coli BL21 (DE3). The expressed proteins were collected by centrifugation and ultrasonic treatment, and then purified by using nickel-nitrilotriacetic acid (Ni-NTA) metal affinity column and dialysis methods. The result of sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) test showed that an expected protein band appeared with a size of 31 kDa. The expressed products possessed antifungal activity against the phytopathogenic indicator strain Botrytis cinerea. A genetically engineered strain tasA of E. coli was established in this study which can efficiently express Tas A protein.     

Explicating <Emphasis Type="Italic">mathematical concept</Emphasis> and <Emphasis Type="Italic">mathematicalconception</Emphasis> as theoretical constructs for mathematics education research

Mathematical understanding continues to be one of the major goals of mathematics education. However, what is meant by “mathematical understanding” is underspecified. How can we operationalize the idea of mathematical understanding in research? In this article, I propose particular specifications of the terms mathematical concept and mathematical conception so that they may serve as useful constructs for mathematics education research. I discuss the theoretical basis of the constructs, and I examine the usefulness of these constructs in research and instruction, challenges involved in their use, and ideas derived from our experience using them in research projects. Finally, I provide several examples of articulated mathematical concepts.     

Antagonistic interaction between <Emphasis Type="Italic">Trichoderma asperellum</Emphasis> and <Emphasis Type="Italic">Phytophthora capsici</Emphasis> in vitro

Phytophthora capsici is a phytopathogen that causes a destructive pepper blight that is extremely difficult to control. Using a fungicide application against the disease is costly and relatively ineffective and there is also a huge environmental concern about the use of such chemicals. The genus Trichoderma has been known to have a potential biocontrol issue. In this paper we investigate the mechanism for causing the infection of T. asperellum against P. capsici. Trichoderma sp. (isolate CGMCC 6422) was developed to have a strong antagonistic action against hyphae of P. capsici through screening tests. The strain was identified as T. asperellum through using a combination of morphological characteristics and molecular data. T. asperellum was able to collapse the mycelium of the colonies of the pathogen through dual culture tests by breaking down the pathogenic hyphae into fragments. The scanning electron microscope showed that the hyphae of T. asperellum surrounded and penetrated the pathogens hyphae, resulting in hyphal collapse. The results show that seven days after inoculation, the hyphae of the pathogen were completely degraded in a dual culture. T. asperellum was also able to enter the P. capsici oospores through using oogonia and then developed hyphae and produced conidia, leading to the disintegration of the oogonia and oospores. Seven days after inoculation, an average 10.8% of the oospores were infected, but at this stage, the structures of oospores were still intact. Subsequently, the number of infected oospores increased and the oospores started to collapse. Forty-two days after inoculation, almost all the oospores were infected, with 9.3% of the structures of the oospores being intact and 90.7% of the oospores having collapsed.     

On the Relationship Between <Emphasis Type="Italic">Belief</Emphasis> and <Emphasis Type="Italic">Acceptance</Emphasis> of Evolution as Goals of Evolution Education

The issue of the proper goals of science education and science teacher education have been a focus of the science education and philosophy of science communities in recent years. More particularly, the issue of whether belief/acceptance of evolution and/or understanding are the appropriate goals for evolution educators and the issue of the precise nature of the distinctions among the terms knowledge, understanding, belief, and acceptance have received increasing attention in the 12 years since we first published our views on these subjects. During that time, our own views about these issues have evolved, and this article presents a reconsideration of both these distinctions and the propriety of these goals. In particular, the present paper continues our discussion of the nature of belief as it relates to science education, and more specifically to evolution education. We extend that work to consider the import of the distinction between belief and acceptance.     

Digital <Emphasis Type="Italic">learning trails</Emphasis>: Scaling technology-facilitated curricular innovation in schools with a <Emphasis Type="Italic">rhizomatic</Emphasis> lens

Technological advances in the form of ubiquitous computing has altered the learning landscape today. Contemporary modes of learning afford curricular innovations in schools. While learning journeys of decades ago entailed field trips to places of interest such as museums and zoos where students completed tasks or worksheets after each trip, the learning journeys of today are facilitated by technological tools such as smart devices and global positioning systems. Learners are moving away from being mere content consumers through technology-facilitated dialoguing and content creation (Tay and Lee 2014; Tan et al. 2011). In this paper we unpack tenets of a technology-facilitated curricular innovation (CI) through a case study analysis of the development and implementation of a Digital Learning Trails (DLT) project. Through tracing the trajectory of the DLT project, we identify factors related to the scalability and sustainability of this CI that was developed in one school and subsequently used by more than 200 schools in Singapore. We posit that scaling curricular innovations in schools can be conceptually provisioned through a rhizomatic lens where innovation is characterized by multiple trajectories, allowing for recontextualizations of CIs. We argue that, (1) the pedagogic process in the context of education and scaling is based on supporting apprentice-schools to make multiple recontextualizations; (2) the enculturation process of a school adopting and implementing a particular innovation is based on a rhizomatic rather than linear, conception of the development of expertise; and (3) the process of CI implementation is based on developing the capability to not only make multiple recontextualizations but also to accumulate enough capital to send out new ‘roots and shoots’ as it spreads.