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Physics‐driven discovery in an autonomous experiment has emerged as a dream application of machine learning in physical sciences. Here, this work develops and experimentally implements a deep kernel learning (DKL) workflow combining the correlative prediction of the target functional response and its uncertainty from the structure, and physics‐based selection of acquisition function, which autonomously guides the navigation of the image space. Compared to classical Bayesian optimization (BO) methods, this approach allows to capture the complex spatial features present in the images of realistic materials, and dynamically learn structure–property relationships. In combination with the flexible scalarizer function that allows to ascribe the degree of physical interest to predicted spectra, this enables physical discovery in automated experiment. Here, this approach is illustrated for nanoplasmonic studies of nanoparticles and experimentally implemented in a truly autonomous fashion for bulk‐ and edge plasmon discovery in MnPS3, a lesser‐known beam‐sensitive layered 2D material. This approach is universal, can be directly used as‐is with any specimen, and is expected to be applicable to any probe‐based microscopic techniques including other STEM modalities, scanning probe microscopies, chemical, and optical imaging. [ABSTRACT FROM AUTHOR]

The IPCC's scientific assessment of the timing of net‐zero emissions and 2030 emission reduction targets consistent with limiting warming to 1.5°C or 2°C rests on large scenario databases. Updates to this assessment, such as between the IPCC's Special Report on Global Warming of 1.5°C (SR1.5) of warming and the Sixth Assessment Report (AR6), are the result of intertwined, sometimes opaque, factors. Here we isolate one factor: the Earth System Model emulators used to estimate the global warming implications of scenarios. We show that warming projections using AR6‐calibrated emulators are consistent, to within around 0.1°C, with projections made by the emulators used in SR1.5. The consistency is due to two almost compensating changes: the increase in assessed historical warming between SR1.5 (based on AR5) and AR6, and a reduction in projected warming due to improved agreement between the emulators' response to emissions and the assessment to which it is calibrated. Plain Language Summary: The IPCC's latest physical science report, the Working Group 1 Contribution to the Sixth Assessment Report (AR6), was released in August 2021. That report includes an update to the tools used to project the climate outcome of emission scenarios. Here we apply these newly calibrated tools, called earth system model emulators, to the set of scenarios assessed in the IPCC's Special Report on warming of 1.5°C (SR1.5). We find that two compensating changes lead to a remarkable consistency (peak warming projections within 0.1°C) between the projections made by the emulators used in SR1.5 and their descendants used in AR6. First, updates to the historical warming assessment since the SR1.5 (which was based on the IPCC's 2013 physical science report (AR5)) increase future warming projections. However, improved consistency between the emulators and the assessment of the underlying physics, particularly the short‐term warming response to emissions, lowers warming projections by an approximately equivalent amount. Our work reinforces the key messages from the IPCC: limiting warming to around 1.5°C is a great and urgent challenge, and it is up to us to decide whether we pull out all the stops to hold temperatures around 1.5°C or whether we sail on by. Key Points: Emulators used in IPCC Special Report on warming of 1.5°C and Sixth Assessment Report are remarkably consistent, despite their entirely new calibrationsThe consistency is due to two compensating factors: change in assessed historical warming and improvements to emulator calibration methods [ABSTRACT FROM AUTHOR]

We describe the development, design, implementation, and preliminary classroom results of an innovative curriculum, Focus on Energy, that supports learning about energy in Grades 4–5. The curriculum is grounded in the concepts of science as practice, model‐based reasoning, and learning progressions, and builds on students' pre‐existing ideas and resources. We illustrate how students gradually develop the ability to track energy forms, transfers, and transformations in increasingly complex scenarios. We present evidence, using a quasi‐experimental design, that students who completed the curriculum were significantly more adept at these skills than students in comparable classrooms who experienced their districts' existing energy‐related physical science curricula. Important features of the curriculum include: the careful selection of a limited set of concepts chosen to provide a sound foundation for future learning; a consistent conceptual framework (the Energy Tracking Lens) within which the students have agency to build and refine a model of energy; engaging hands‐on activities that steadily build in complexity; accessible and versatile semi‐quantitative representations that support reasoning and communication; individual, small‐group and large‐group meaning‐making; and training and support for the teachers. [ABSTRACT FROM AUTHOR]

In the United States, research on beginning science teachers provides little guidance regarding empirical minimum levels of discipline‐specific science coursework for sufficient subject matter knowledge to teach science. Accordingly, in this study we analyzed secondary physical science teachers' science coursework for subject matter knowledge (SMK) and resulting misconceptions of chemistry and physics concepts. Findings were compared with state‐level science teacher certification policies. Participants had either: (a) completed a master's level teacher preparation program with an undergraduate degree in science, (b) completed an undergraduate teacher preparation program with a minor degree or more in science, or (c) were undergraduate students enrolled in science courses required for chemistry and physics teacher certification. We analyzed participants' transcripts for discipline‐specific science coursework credit hours and GPAs and identified possible predictors of SMK predictors of the likelihood of passing chemistry and physics misconceptions tests. We categorized teachers' level of SMK and used multiple variable and logistic regressions (n = 212 participants; n = 109 chemistry and n = 103 physics). To identify teacher candidates' possible misconceptions, we analyzed chemistry (n = 97) and physics (n = 91) participants' item responses with the corresponding science credit hours and GPAs. With increasing numbers of credit hours teachers held fewer misconceptions. However, even with medium to high SMK levels, teachers still held misconceptions about chemical bonding, electromagnetism, and Newton's laws until they reached critical credit hour and GPA thresholds. Lastly, we provide recommendations for physical science teachers' programs of study and state‐level teaching certification policies, using empirical minimum quantity and quality of chemistry, physics, and mathematics coursework. [ABSTRACT FROM AUTHOR]

An object-based evaluation method using a pattern recognition algorithm (i.e., classification trees) is applied to the simulated orographic precipitation for idealized experimental setups using the National Center of Atmospheric Research (NCAR) Community Atmosphere Model (CAM) with the finite volume (FV) and the Eulerian spectral transform dynamical cores with varying resolutions. Daily simulations were analyzed and three different types of precipitation features were identified by the classification tree algorithm. The statistical characteristics of these features (i.e., maximum value, mean value, and variance) were calculated to quantify the difference between the dynamical cores and changing resolutions. Even with the simple and smooth topography in the idealized setups, complexity in the precipitation fields simulated by the models develops quickly. The classification tree algorithm using objective thresholding successfully detected different types of precipitation features even as the complexity of the precipitation field increased. The results show that the complexity and the bias introduced in small-scale phenomena due to the spectral transform method of CAM Eulerian spectral dynamical core is prominent, and is an important reason for its dissimilarity from the FV dynamical core. The resolvable scales, both in horizontal and vertical dimensions, have significant effect on the simulation of precipitation. The results of this study also suggest that an efficient and informative study about the biases produced by GCMs should involve daily (or even hourly) output (rather than monthly mean) analysis over local scales. [ABSTRACT FROM AUTHOR]

Three-dimensional reconstruction of developing fiber pathways is essential to assessing the developmental course of fiber pathways in the whole brain. We applied diffusion spectrum imaging (DSI) tractography to five juvenile ex vivo cat brains at postnatal day (P) 35, when the degree of myelination varies across brain regions. We quantified diffusion properties (fractional anisotropy [FA] and apparent diffusion coefficient [ADC]) and other measurements (number, volume, and voxel count) on reconstructed pathways for projection (cortico-spinal and thalamo-cortical), corpus callosal, limbic (cingulum and fornix), and association (cortico-cortical) pathways, and characterized regional differences in maturation patterns by assessing diffusion properties. FA values were significantly higher in cortico-cortical pathways within the right hemisphere compared to those within the left hemisphere, while the other measurements for the cortico-cortical pathways within the hemisphere did not show asymmetry. ADC values were not asymmetric in both types of pathways. Interestingly, tract count and volume were significantly larger in the left thalamo-cortical pathways compared to the right thalamo-cortical pathways. The bilateral thalamo-cortical pathways showed high FA values compared to the other fiber pathways. On the other hand, ADC values did not show any differences across pathways studied. These results demonstrate that DSI tractography successfully depicted regional variations of white matter tracts during development when myelination is incomplete. Low FA and high ADC values in the cingulum bundle suggest that the cingulum bundle is less mature than the others at this developmental stage. [ABSTRACT FROM AUTHOR]

A stream of debate (including a previous special issue of this journal (25(1) 2014)) has made claims not just for 'bringing knowledge back in' as the framing underpinning of the school curriculum, but that subjects associated with disciplinary and disciplined knowledge forms have a particular power and that these characteristics are important to preserve in curriculum frameworks. This paper draws on a major Australian research project studying school and university physics in the context of these arguments to revisit the issue of the 'discipline' of physics and the curriculum logics for physics. Given that disciplines are social in origin and changing and expanding over time, can school curriculum be logically derived from the discipline to which they relate? Are questions about student engagement only questions about pedagogy and not curriculum? Does a focus on disciplinary knowledge mean that the role of school in forming identities and values is avoidable as a significant feature of what the curriculum does? The findings from the project are used both to illustrate and test these questions, and to challenge some over-simple assumptions about the verticality of this form of knowledge for education purposes. [ABSTRACT FROM AUTHOR]

The table of contents for the April 2015 issue of the journal "Annalen der Physik" is presented.

The table of contents for the July 2014 issue of the "Physica Status Solidi" is presented.

The table of contents for the December 1, 2013 issue of "Physica Status Solidi-Rapid Research Letters" is presented.

Fractional scoring has been proposed to avoid inconsistencies in the attribution of publications to percentile rank classes. Uncertainties and ambiguities in the evaluation of percentile ranks can be demonstrated most easily with small data sets. But for larger data sets, an often large number of papers with the same citation count leads to the same uncertainties and ambiguities, which can be avoided by fractional scoring, demonstrated by four different empirical data sets with several thousand publications each, which are assigned to six percentile rank classes. Only by utilizing fractional scoring does, the total score of all papers exactly reproduce the theoretical value in each case. [ABSTRACT FROM AUTHOR]

The article provides information on a study which described the ways in which BluIce was combined with Experimental Physics and Industrial Control System (EPICS) and converted into the Java-based JBluIce. The solutions aimed at streamlining and speeding up operations are described. An overview of the tools that are provided by the open-source control system for facilitating crystallographic experiments is presented. A review of the structure and functionality of EPICS and SSRL BluIce is given.

The revolution in science inaugurated by quantum physics has made us aware of the role of observation in the construction of data. Eugene Wigner remarked that in quantum physics we no longer have observables (invariants), only observations. Tongue in cheek, I asked him whether that meant that quantum physics is really psychology, expecting a gruff reply to my sassiness. Instead, Wigner beamed understanding and replied “Yes, yes, that's exactly correct.” David Bohm pointed out that were we to look at the cosmos without the lenses of our telescopes we would see a hologram. I extend Bohm's insight to the lens in the optics of the eye. The receptor processes of the ear and skin work in a similar fashion. Without these lenses and lenslike operations all of our perceptions would be entangled as in a hologram. Furthermore, the retina absorbs quanta of radiation so that quantum physics uses the very perceptions that become formed by it. In turn, higher-order brain systems send signals to the sensory receptors so that what we perceive is often as much a result of earlier rather than just immediate experience. This influence from inside out becomes especially relevant to our interpretation of how we experience the contents and bounds of cosmology that come to us by way of radiation. [ABSTRACT FROM AUTHOR]

The photophysics of a number salicylic acid derivatives (SADs) in aqueous solutions was investigated in a wide range of pH by time-correlated single photon counting (λex = 350 nm, τresp = 300 ps) and fluorescence up-conversion (λex = 266 nm, τresp = 300 fs) techniques. The acid–base equilibrium constants in the ground (pKa) and the excited states (${\rm p}K_{\rm a}^* $), the fluorescence quantum yields as well as the lifetimes of anionic, neutral, and cationic forms of SADs were determined. Evidence of ultrafast excited-state intramolecular proton transfer (ESIPT) leading to the formation of the proton-transferred excited state of SADs was obtained from the fluorescence up-conversion measurement. The nature of the ESIPT process is discussed. Copyright © 2008 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The article discusses a form of reductionism based on the thinking pf Murray Gell-Mann and James Hartle. The new reductionism is based on discoveries in quantum physics and on a program by Gell-Mann and Santa Fe Institute on complexity and emergence. The new reductionism has been neglected by philosophers due to the technical nature of the papers as well as the focus on structures and dynamics. The article discusses several types of reductionism including epistemological, ontological, and methodological. An overview of the new reductionism is provided.

This article is devoted to an observation artefact arising in near-field optical calculations by methods with the discretization of a scattering object and the substitution of separated dipoles instead of discretizing meshes. It is discussed that such an artificial discretization gives within the object a non-monotonously changing field on the scale of the discretizing mesh size, which propagates from the object to a distance of the same order of magnitude as the mesh size in contrast to the real situation where such a non-monotonously changing fields exist on the scale of a real atomic lattice. If such a non-monotonously changing field exists in the observation plane where the picture is calculated, the choice of the observation points can change the obtained picture remarkably. [ABSTRACT FROM AUTHOR]

The article reports on the use of the physics-based model known as the Integrated Hydrology Model in simulating continuous hydrologic response and event-based sediment transport for the R-5 catchment. The sediment-transport simulations were conducted in one-year periods for a total of six years. The sediment-transport simulations were conducted for six selected events. The multi-year water-balance results from the hydrologic-response simulations match the observed aggregate behavior of the catchment. Event hydrographs were generally simulated best for the larger events.

We present the development of a LabVIEW multimedia module for introductory Quantum Physics courses and our experience in the use of this application as an educational tool in learning methodologies. The program solves the time-dependent Schrödinger equation (TDSE) for arbitrary potentials. We describe the numerical method used for solving this equation, as well as some mathematical tools employed to reduce the calculation time and to obtain more accurate results. As an illustration, we present the evolution of a wave packet for three different potentials: the repulsive barrier potential, the repulsive step potential, and the harmonic oscillator. This application has been successfully integrated in the learning strategies of the course Quantum Physics for Engineering at the Polytechnic University of Valencia, Spain. © 2007 Wiley Periodicals, Inc. Comput Appl Eng Educ. 15: 124–133, 2007; Published online in Wiley InterScience (www.interscience.wiley.com); DOI 10.1002/cae.20100 [ABSTRACT FROM AUTHOR]

Two fundamental issues raised by Lothar Schäfer are considered: (1) the question of a suitable paradigm within which the findings of quantum physics can be optimally interpreted and (2) the question of the assessment of the presence and importance of mind and consciousness in the universe. In regard to the former, I contend that the ideal of science is to interpret its findings in an optimally consistent and minimally speculative framework. In this context Schäfer's assertion that certain findings in quantum physics (those that relate to virtual states) indicate the presence of mind at the quantum level implies a dualistic and hence unnecessarily speculative assumption. In regard to the assessment of mind and consciousness, a consistent and parsimonious paradigm suggests that mind and consciousness are not part of a chain of events consisting of an admixture of physical and mental events but that physical events form a single, coherent set of events, and mental events another set, with the two sets related, as Teilhard (and a number of other philosophers, including White head) affirmed, as the “within” and the “without” (or the “mental pole” and the “physical pole”) of one and the same fundamental reality. This panpsychist as contrasted with Schäfer's dualist paradigm provides a single self-consistent framework for the interpretation of quantum (and all natural) events while recognizing the presence of mind in the universe as the least speculative realist implication of our immediate experience of consciousness. [ABSTRACT FROM AUTHOR]

The article 1 discusses selected findings of a narrative review, funded by the Institute of Physics,2 in response to the continuing decline in the number of girls studying physics post-16 in England; 177 selected sources, of national and international research literature about girls' participation in physics, were reviewed. In the article, we argue that gender and science are mutually constitutive and girls' participation in physics education, historically and currently, needs to be understood in relation to this. Prior achievement and perceptions of the difficulty of physics are determinants of students' decisions about whether to continue to study physics. These influences may be heightened for girls by gendered associations about who is, and is not, competent in mathematics and physics. Interest and enjoyment in physics also influence students' course choices, particularly those of girls, and these decline relative to other sciences through schooling, more so for girls than boys. This decline is not disrupted by school organization. Single-sex organization is associated with high teacher expectations in science and a greater sense of ‘belonging’ for girls, but not for all girls. The contents, contexts and ways of approaching problems and investigations in physics more closely reflect what boys, more than girls, engage with outside school, and those activities associated with what culture defines as masculine rather than feminine attributes. These exert a negative influence on girls' engagement with physics, their sense of self-efficacy in relation to it, and their perception of its personal relevance. Girls, relative to boys, continue not to see a future self engaged in physics and physics-related careers. This can be disrupted by changes in the curriculum and in pedagogy. Context-based courses alter how physics content is organized, and impact positively on overall performance, and on girls' performance relative to that of boys. They also raise fundamental challenges to physics education and its perceived educational purpose. Developments in science education in England, we suggest, do not challenge the gender–science relationship and their impact on girls' participation may be limited as a consequence. The article highlights the paucity of UK-based research generally into girls' participation in physics, and particularly into pedagogy that enhances participation for girls from a variety of different ethnic and socio-economic backgrounds. [ABSTRACT FROM AUTHOR]

The title compound poly[[bis(μ-2-carboxylatoethylphosphonato)cadmium] dihydrate], Cd3(O3PC2H4CO2)2·2H2O, was prepared by a hydrothermal reaction and its crystal structure determined from in-house powder data. The structure was solved in both P21/ c and P21 space groups. The refinement converged with Rp = 0.1046, Rwp = 0.1378 and Rf = 0.0763 in P21/ c. However, the solid-state NMR data could not be explained. The structure was then solved in P21 and the refinement converged with Rp = 0.0750, Rwp = 0.1022 and Rf = 0.0409 and satisfied the NMR requirements. [ABSTRACT FROM AUTHOR]

This paper examines a noncontact energy transfer system which can stabilize the load voltage with no-feedback control. A detachable transformer used in the system has a leakage inductance. Therefore, load voltage decreases greatly in proportion to load current. A feedback control circuit of the noncontact energy transfer system is more complicated than that of the contact energy transfer system. Consequently, even if without feedback control, a noncontact energy transfer system which can maintain the approximate fixed load voltage is required. The authors have analyzed the load voltage characteristic in detail and researched the mechanism, and found a novel method which minimizes the load voltage drop rate by using optimized capacitance value of two resonant circuits. © 2005 Wiley Periodicals, Inc. Electr Eng Jpn, 151(2): 63–74, 2005; Published online in Wiley InterScience (www.interscience. wiley.com). DOI 10.1002/eej.20032 [ABSTRACT FROM AUTHOR]

A method was developed and implemented for predicting enthalpies of gas hydrate formation, which are required for the efficient design of gas hydrate-based processes. The proposed method is based on the statistical thermodynamic theory of solid solutions and it is thermodynamically consistent. It allows delineation of the various energetic contributions, does not resort to empirical constants enforced by regressions and applies to any simple or multicomponent bulk hydrate equilibrium system at the hydrate point or beyond it. The application of the method was demonstrated for several simple, double and multicomponent gas hydrate systems with one or two equilibrium hydrate phases. It was found that a major energetic component in hydrate formation is the heat of enclathration, defined as the residual enthalpy of the enclathrated gas. All example applications indicated that this property is a constant, independent of temperature, pressure and composition, characteristic only of the individual gas and it was regressed by a general corresponding states analytical expression. [ABSTRACT FROM AUTHOR]

The structure of Na0.8Ti1.2Ga4.8O10 was determined by means of single-crystal X-ray diffraction at 173 and 123 K and reinvestigated at 299 K. The host structure containing one-dimensional tunnels was retained over the temperatures examined, while significant changes were observed in the probability density distribution of Na+ ions in the tunnel. The refinement based on the local structure model with the deviated Na+ ion neighboring the vacancy gave a similar result to that from the conventional model, but with reduced standard uncertainties of the structural parameters for the Nat ions. The potential barrier for the Na+ ion hopping between adjacent cavities was estimated to be ca 30–40 meV from the joint probability density function of deviated Na+ ions. [ABSTRACT FROM AUTHOR]

One of the key obstacles in the progress of certain aspects of solid-state physics is the determination of the nature of irregularities in the atomic network of matter and their correlation with macroscopic properties. In this work, an original structural result is presented, namely the presence of icosahedral clusters in an Al solid solution, as deduced from the analysis of the total Fourier- space image. This work has led to the belief that these non-crystalline clusters create a fundamental irregularity in the network of a non-ideal solid solution. [ABSTRACT FROM AUTHOR]

A survey is given of several key themes that have characterised mathematics in the 20th century. The impact of physics is also discussed, and some speculations are made about possible developments in the 21st century. 2000 Mathematics Subject Classification 00-02. [ABSTRACT FROM PUBLISHER]

All of reality derives from disturbances to equilibrated states (controlled systems). This realization allows one to develop a generic feedback/feedforward control model as a paradigm for all of the laws of physics. The model is formulated from seven fundamental axioms, upon which are based seven corresponding theorems--among them, the one that defines Potential Energy as the source for all of reality. The output--Kinetic Energy--of the model is experienced (feedback signals which are in the form of dimensions of perception: including time, length, mass, temperature and electric charge) by an observer (frame-of-reference) along a doubly-infinite continuum that is arbitrarily divided into seven scales of perception. These range from sub-nuclear to super-cosmic. Adding to scale-of-perception and frame-of-reference the concept of resolution--which includes considerations of structure, order, and relation--completes the tripartite set of elements that are the foundations of knowledge. A minimum-energy principle (controlling system) is introduced to close the loop in the control model. Operationally, this constraint is manifest as "control signals" that attenuate the randomness of transitions among quasi-equilibrated states, forcing such perceived transitions to proceed along optimized paths ("reference signals" in the control model). [ABSTRACT FROM AUTHOR]

The theory of evolution of cooperation presents a number of striking similarities to the theory of phase transitions in physics. A system that is in a higher energy phase P+ will make a transition to a lower energy phase P-, given enough time, as long as the intervening energy barrier is not too high. The phase transition is realized through the nucleation of a sufficiently large bubble of the energetically preferred phase P- within the higher energy phase P+. Similarly, if we think of the strategies of Defection and of Tit for Tat as the phases P+ and P- respectively, a population using the ‘energetically unfavourable’ Defection strategy will switch over to the ‘energetically favourable’ Tit for Tat strategy, provided the players interact continuously and substantially. The presence of a large enough Tit for Tat concentration is necessary for the onset of this change. Copyright © 2001 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Combined analysis of co-citation relations and words is explored to study time-dependent ("dynamical") aspects of scientific activities, as expressed in research publications. This approach, using words originating from publications citing documents in co-citation clusters, offers an additional and complementary possibility to identify and link specialty literature through time, compared to the exclusive use of citations. Analysis of co-citation relations is used to locate and link groups of publications that share a consensus concerning intellectual base literature. Analysis of word-profile similarity is used to identify and link publication groups that belong to the same subject-matter research specialty. Different types of "content-words" are analyzed, including indexing terms, classification codes and words from title and abstract of publications. The developed methods and techniques are illustrated using data of a specialty in atomic and molecular physics. For this specialty, it is shown that, over a period of 10 years, continuity in intellectual base was at a lower level than continuity in topics of current research. This finding indicates that a series of interesting new contributions are made in course of time, without vast alteration in general topics of research. However, within this frame- work, a more detailed analysis based on timeplots of individual cited key-articles and of content-words reveals a change from more rapid succession of new empirical studies to more retrospective, and theoretically oriented studies in later years. [ABSTRACT FROM AUTHOR]

Combined analysis of co-citation relations and words is explored to study time-dependent ("dynamical") aspects of scientific activities, as expressed in research publications. This approach, using words originating from publications citing documents in co-citation clusters, offers an additional and complementary possibility to identify and link specialty literature through time, compared to the exclusive use of citations. Analysis of co-citation relations is used to locate and link groups of publications that share a consensus concerning intellectual base literature. Analysis of word-profile similarity is used to identify and link publication groups that belong to the same subject-matter research specialty. Different types of "content-words" are analyzed, including indexing terms, classification codes and words from title and abstract of publications. The developed methods and techniques are illustrated using data of a specialty in atomic and molecular physics. For this specialty, it is shown that, over a period of 10 years, continuity in intellectual base was at a lower level than continuity in topics of current research. This finding indicates that a series of interesting new contributions are made in course of time, without vast alteration in general topics of research. However, within this frame-work, a more detailed analysis based on timeplots of individual cited key-articles and of content-words reveals a change from more rapid succession of new empirical studies to more retrospective, and theoretically oriented studies in later years. [ABSTRACT FROM AUTHOR]

A synchronous citation study of 15 leading Physical journals has been performed to determine the absolescence of Physical Review articles with age. The density of citations to Physical Review has been found to decrease exponentially with a half-life of first of 4.9 years, which is the first conclusive evidence of the exponential decrease. [ABSTRACT FROM AUTHOR]

Magnetic resonance imaging is a new diagnostic technique that is being applied to study disease processes that involve the upper aerodigestive tract and cranial nerves of interest to otolaryngologists. As with all imaging techniques, an in-depth knowledge of the normal anatomy of a region is a prerequisite for the appreciation of disease states. In addition, magnetic resonance imaging requires a familiarity with the signal intensity produced by the different structures and the relationship of that signal to various radiofrequency pulse sequences that may be used. This report briefly reviews the techniques of magnetic resonance imaging and the normal anatomy of the cervical region and presents examples of pathologic processes that have been studied with this powerful diagnostic technique. [ABSTRACT FROM AUTHOR]

The article focuses on the survey that documents the continuing crisis in the supply and demand for high school physics and chemistry teachers in Kansas. The three variables namely, the age-specific variable of science teacher survival rates, incoming number of new teachers, and the rate at which teachers change age cohorts, were used in a five-year longitudinal study of all the physics and chemistry teachers to project the need for additional staff. Moreover, the age frequency for the chemistry and physics teachers is discussed.

The article focuses on the use of general learner objectives for the design, development and evaluation of an instructional program to attain the course objectives in physics. In measuring student attainment of course objectives, open-book written examinations were used in the course. Furthermore, attempts have been made to determine how the final student attainments with respect to the different objectives, are statistically related to academic achievements. Moreover, experience in the measurement of student attainment of the course objectives are discussed.

The article cites a study on the relationship between motivation and academic achievement to physics students in the U.S. The researcher used three types of motivation including, motivation in the satisfaction of needs for security and belongingness, satisfaction of self-esteem motivation, and motivation for the satisfaction of growth needs. Sample chosen was the second-year college students in health science program. This study revealed that motivation related to that satisfaction of needs did not correlate on the students' achievement in physics.

The aim of this article is to use examples drawn from physics to argue that the conceptual change depiction of learning should be extended to include conceptual fitting based upon context. A review of the students' conceptions literature reveals that the notion of conception is seldom made explicit. There are, however, often discernable implicit, and sometimes explicit, differences reflecting underlying epistemological variations framing the various studies. The mental model perspective depicts conceptions as tangible inside-head constructs made up of structured propositional patterns of reasonings. The experiential perspective, made explicit by the Gothenburg University phenomenography researchers, depicts conceptions as being characterizations of categories of description reflecting person-world relationships embodied in the German philosopher Franz Bretano's notion of intentionality--one does not just conceptualize, one conceptualizes something. In other words, phenomenographically a conception has both structure and meaning.

The article discusses the relative physics achievement at three levels of cognitive complexity between Thai and American 10 and 13 year old children. An assessment of the cognitive comprehension level of a concept allows the prediction of what content achievement capabilities the student is capable of attaining in a series of related concepts. The comprehension of a concept at the compensatory level may be sufficient for general scientific literacy purposes. The pictorial test used in the study is called Test of Elementary Physical Science Cognitive Structure (TEPSCS). Older children of both cultures performed better than did the younger children at all logical complexity levels.

Within the framework of the Second IEA Science Study a representative sample of Israeli 12th grade students (N=2153) responded to a series of questionnaires and achievement tests in the last term of the academic years 1983 or 1984. The sample consisted of four groups, three of which specialising each in one of the sciences (biology, chemistry and physics) and one comprised of students who did not study any science in their junior and senior years. The purpose of this paper is to report on gender differences in achievement, attitudes, preferences, learning experiences and study habits. The major findings were as follows. (1) The percentage of girls in each of the specialising groups are as follows. Biology: 61; chemistry: 49; physics: 31, non-science: 66. (2) More boys perceive themselves as high achievers in science and math. (3) Significantly more boys like to study math and science more than other school subjects. (4) Significantly more boys aspire for science-oriented careers. (5) Boys achieve better than girls in physics and in earth science, but their achievement in biology and chemistry is similar to that of girls. The achievement of non-science girls is alarmingly low and with the exception of biology much lower than that of boys. (6) Boys have more positive attitudes toward science and better understanding of the nature of science. (7) Girls express more positive attitudes to school but boys are more interested in science studies. (8) There are no differences in cognitive preferences. (9) Girls report on having more inquiry oriented experiences. (10) More boys aspire for scientific research and engineering careers. Relatively more girls aspire for medical careers. The implications of these findings for science education in general and in Israel in particular are discussed. [ABSTRACT FROM AUTHOR]

The science choices, attitudes and achievement of Asian and black children were compared with those of white children. When allowance was made for background and school factors there was very little difference between the ethnic groups in the extent to which they enroled in science courses in fourth and fifth year. Asian boys were slightly more likely than other boys to choose physics; they also expressed greater liking for science and greater interest in learning about physical science than other boys. White girls were less interested in physical science than other girls and white boys were less interested in biology. Black and Asian pupils scored lower than comparable white children on science tests on entry to secondary school. However by fifth year Asian boys were out-performing white boys, while black pupils achieved as well as white children from similar backgrounds and schools. [ABSTRACT FROM AUTHOR]

The author claims that the use of formal methods in philosophy is not overwhelming compared with the empirical disciplines, such as mathematics and physics. He notes that physics had access to the mathematical medium centuries before it learnt how to avail itself of the bridge, unlike philosophy wherein it has a mathematical medium but do not have the bridge of measurement. He says that in philosophy, empirical observations cannot support or disprove a theoretical statement very clearly.

The purpose of this investigation was to reveal the use patterns of the physics journals in the M.l.T. Science Library. The findings are based upon an analysis of actual use data recorded from all volumes and issues left by library users on study tables and on trucks in the photocopy area from March 1 5 to June 31, 1971. The Science Library contains some 220 physics journals. The study reveals that only 138 journals (62.7%) were used even once during the 3 Vi-month interval. A core of 49 journals supplies 90% of use, and these titles would cost 51.5% of the total single subscription costs of the 138 used titles: 52.3% of use occurs in journal volumes less than 6 years old. English is the most used language of physics journals and the English journals account for 95.3 %, of use. American journals, 57.2% of which are published by the American Institute of Physics, supply 59.4% of the total use. [ABSTRACT FROM AUTHOR]

The article presents a study that attempts to determine the relative effectiveness of studying chemistry and physics in a two year integrated course and in the more conventional separate one year courses of chemistry and physics. Comparison were made in the development of understanding of science, scientists and techno methods of science and reactions to the study of science. The study was confined to a single high school. According to the result of the study, the two year physics-chemistry course produced significantly greater achievement in the understanding of the concepts of physics than that of the conventional style.

The article focuses on the foundation and intent of physical science museums in the U.S. These museums are much more recent establishments which aim to acquaint visitors with the principles of physics, chemistry and earth sciences. The earth science exhibits were subdivided into astronomy, geology, meteorology and space science. From an examination, astronomy exhibits dominate the field than those in geology or meteorology. The earth science field is one of the recent expansion and is expected to find a prominent place in science museums.

The article discusses the development of the project known as the Engineering Concepts Curriculum Projects (ECCP), under the sponsorship of the Commission on Engineering Education. According to the article, the project aims to link the physical principles to the man-made world and associate them in with the study of systems, processes and devices man has created to cope with nature. The article also deals with the development of the Harvard Project Physics course which aims to produce a model built upon the concept of a historical and cultural approach to physics.

The article presents an evaluation of the new physics course called Harvard Project Physics. The study plans to determine the characteristics of a group of students recruited into a physics course by teachers and counselors and compare the observed changes of the recruited group with the observed changes of those students who had decided to take physics on their own. It states that the physics course aims to create a set of materials that may help check the continuing decrease in the number of students taking physics in high school. The course also intends to catch the interest of the large, untapped group of students who lacks interest in taking up the course.

The article discusses the relation of teachers' attitudes to the declining percentage enrollments in physics. The United States Office of Education (USOE) figures reveal that 19.6 percent of all public school twelfth graders were enrolled in a first year physics course in 1964 to 1965. A study has been conducted to report data concerning the validity of reasons frequently given for low physics enrollments. Some reasons include stress on course difficulty, unfair grading standards, college preparatory function, and teacher shortages.

The article reports on the development of a course of study in space science suitable for instruction in the ninth and tenth grades in the secondary school. The participants of the study were part of the top five percent of their class who were recommended by the principals of their schools. The method and research design involved the technique used in developing curricular materials and selection of the fundamental ideas of the physical sciences. The study focused on ideas in the fields of chemistry, physics, astronomy, and mathematics.