This paper presents an analysis of the thermal behaviour of objects exposed to a solar-type flux of thermal radiation. It aims to clarify certain apparent inconsistencies between theory and observation, and to give a detailed exposition of some critical points that physics textbooks usually treat in an insufficient or incorrect way. In particular,…

Sense About Science is a UK-based charitable trust that equips people to make sense of science and of evidence on issues that matter to society. It was set up in 2003 in response to newspaper front pages being full of headlines about mobile phones "frying your brain", genetically modified "Frankenstein foods", the MMR vaccine,…

Derivation of the law of radioactive decay is considered without prior knowledge of calculus or the exponential series. Calculus notation and exponential functions are used because ultimately they cannot be avoided, but they are introduced in a simple way and explained as needed. (Contains 10 figures, 1 box, and 1 table.)

Cerebral small vessel disease is the most common cause of vascular cognitive impairment. It typically manifests with lacunar infarcts and ischaemic white matter lesions. However, little is known about how these lesions relate to the cognitive symptoms. Previous studies have found a poor correlation between the burden of ischaemic lesions and…

The idea of using a dice game to simulate radioactive decay is not new. However, modern pedagogy encourages, if not requires, us to provide multiple representations and visualizations for our students. The advantage of interactive engagement methods also has been made clear. Here we describe a highly visual and interactive use of dice to develop…

Information and communication technology (ICT) is a natural part of most people's everyday life, and has also been introduced in schools. Previous studies have tended to focus on issues related to competency of teachers and lack of computer technology in schools. Focus now seems to be moving towards studies that help us understand how ICT may be…

Adopting activity theory as a theoretical and methodological framework, this case study illustrates how a teaching and learning situation is planned and implemented over a series of nine 75-min biology classes by a high school science teacher in the context of pedagogical reform. The object of this study emerges within a favourable context of…

The purpose of this study was to determine whether increased levels of UV radiation and temperatures from global warming have a significant impact on dissolved oxygen (DO) output from the alga, "Euglena," which affects other organisms in the ecosystem. The original hypothesis stated that if temperature was increased along with exposure time to…

A technique has previously been described for secondary school-aged children to make ultraviolet (UV) dosimeters from highlighter pen ink drawn onto strips of paper. This technique required digital comparison of exposed ink paper strips with unexposed ink paper strips to determine a simple calibration function relating the degree of ink fading to…

This essay presents the use-first-and-investigate-later (UFAIL) approach to technological use through two case studies: the atomic bomb in World War II and chemical defoliants during the Vietnam War. The methodology of UFAIL is as follows: despite limited understanding of an array of potential effects (medical, environmental, etc.), technology…

Silently, invisibly, ceaselessly, our planet Earth is showered by radio waves from every direction and from every region of space. This radio energy originates in our solar system, throughout the Milky Way galaxy, and far beyond, out to the remotest reaches of the universe. Detecting and unraveling the origins of these invisible signals is what…

New science standards and reform recommendations spanning grades K--16 focus on a limited set of key scientific concepts from each discipline that all students should know. They also emphasize the integration of these concepts with science practices so that students learn not only the "what" of science but also the "how" and…

Objective: Follow-up skeletal surveys have been shown to improve the rate of fracture detection in suspected cases of non-accidental trauma (NAT). As these studies are performed in a particularly radiosensitive population, it is important to evaluate if all of the (approximately 20) radiographs obtained at repeat skeletal survey are clinically…

This paper deals with temperature variations over time of objects placed in a constant-temperature environment in the presence of thermal radiation. After a historical introduction, the paper discusses cooling and warming laws, by taking into account first solely object-environment energy exchange by thermal radiation, and then adding…

This thesis outlines how meV-resolution inelastic x-ray scattering and causality-enforcing mathematics can be used to measure the dynamical density-density linear response function for liquid water with Angstrom spatial resolution and 50fs temporal resolution. The results are compared to high-resolution spectroscopic and scattering experiments and…