This article describes a simple and robust laboratory exercise on the regulation of membrane unsaturated fatty acid composition in bacteria by a decrease in growth temperature. We take advantage of the well characterized Des pathway of "Bacillus subtilis", composed of a [delta]5-desaturase (encoded by the "des" gene) and the canonical…

This paper investigates the classification of shapes into broad natural categories such as "animal" or "leaf". We asked whether such coarse classifications can be achieved by a simple statistical classification of the shape skeleton. We surveyed databases of natural shapes, extracting shape skeletons and tabulating their…

The use of an internal standard is a conventional and convenient way to monitor the conversion of one or several monomers during a controlled radical polymerization. However, the validity of this technique relies on an accurate determination of the initial monomer-to-internal standard ratio, A[subscript 0], because all subsequent calculations of…

Terms to be familiar with before you start to solve the test: chromatin, nucleases, sucrose density gradient centrifugation, melting point, gel electrophoresis, ethidium bromide, autoradiography, Southern blotting, Northern blotting, Sanger sequencing, restriction endonucleases, exonucleases, linker DNA, chloroform extraction, nucleosomes,…

Positive emotions are often treated as relatively similar in their cognitive-behavioral effects, and as having unambiguously beneficial consequences. For example, Valdesolo and DeSteno (2006) reported that a humorous video made people more prone to choose a utilitarian solution to a moral dilemma. They attributed this finding to increased positive…

Three conditioned suppression experiments examined the Hall-Pearce (1979) negative transfer effect in rats. Experiment 1 replicated the effect: CS-US[subscript weak] pairings retarded subsequent fear conditioning to the CS as a result of CS-US[subscript strong] pairings. The size of this retardation was less than that produced by non-reinforced CS…

This study investigates the contribution of the left and right hemispheres to the comprehension of bilingual figurative language and the joint effects of salience and context on the differential cerebral involvement in idiom processing. The divided visual field and the lexical decision priming paradigms were employed to examine the activation of…

The production of bioethanol from cellulosic waste is described. The experiment is suitable for students in secondary school classroom settings and leads to bioethanol in a concentration high enough to burn the liquid. The experiment consists of three steps: (i) the cellulose of the waste material is converted to glucose by cellulase enzymes, (ii)…

This paper presents a comparison of online to traditional face-to-face delivery of undergraduate digital systems material. Two specific components of digital content were compared and evaluated: a sophomore logic circuits course with no laboratory, and a microprocessor laboratory component of a junior-level computer systems course. For each of…

The exponential growth of advancing technologies is pushing curriculum designers in computer engineering (CpE) education to compress more and more content into the typical 4-year program, without necessarily paying much attention to the cohesiveness of those contents. The result has been highly fragmented curricula consisting of various…

Science is at heart a practical subject, but the perception of what makes good teaching and learning through practical science is often misunderstood. Through working with teachers on professional development courses at the UK's National Science Learning Centre, and drawing on work carried out by other organisations, we present some thoughts and…

Learning styles are increasingly being integrated into computational-enhanced earning environments and a great deal of recent research work is taking place in this area. The purpose of this study was to examine the impact of the computational experiment approach, learning styles, epistemic beliefs, and engagement with the inquiry process on the…

In Germany, science education standards for students at the end of grade nine have been in existance since 2005. Some of these standards are dedicated to scientific inquiry (e.g. experimentation). They describe which abilities learners are expected to possess at the end of grade nine. In the USA, several documents describe standards for…

Traditional lecturing has been shown again and again to be a less effective teaching method regarding student engagement and promotion in the sciences. Studies that compare different teaching methods often face limitations because, over time, courses are either substantially changed and/or are taught by different instructors. This article presents…

In traditional teaching, the fundamental concepts of electromagnetic induction are usually quickly analyzed, spending most of the time solving problems in a more or less rote manner. However, physics education research has shown that the fundamental concepts of the electromagnetic induction theory are barely understood by students. This article…