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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]

The table of contents for the April 2016 issue of the journal "Angewandte Chemie International Edition" is presented.

A table of contents for the issue is presented.

This Review is focused on radicals and dormant species in biology and polymer chemistry. The past two decades have witnessed significant advances in understanding the role, and methods of creation and control, of free radicals in biology and polymer chemistry. The progress reached in both areas has been enabled by the mechanistic understanding and fine-tuning of the reactivity, selectivity, and persistency of the radical species in multistep processes. The multidisciplinary scientific scenario described in this Review can be useful not only to create bridges and networks between biologists and chemists, but also to provide science with diversity, thereby highlighting aspects of biology and chemical synthesis that are only apparently far from each other. This should also result in widened scientific horizons, thus triggering a transfer from research to innovation. [ABSTRACT FROM AUTHOR]

The table of contents for the issue is presented.

The table of contents for the July 2015 issue of the journal "Helvetica Chimica Acta" is presented.

An author index for an early 2015 issue of the "ChemInform" journal is presented.

The table of contents for the August 25, 2014 issue of "Chemistry--A European Journal" is presented.

An author index for the August 2014 issue of "Wiley Online Library" is presented.

ABSTRACT In this study, we compared non-forested and forested habitat types of a degraded bog in Western Germany with regard to the base cation chemistry of their pore waters. Peat profiles were sampled in 10-cm intervals every month from April to July 2009 down to a maximal depth of 150 cm. Pore waters were analysed for Ca, Mg, K and Na concentrations. Additionally, electrical conductivity and pH were measured in surface pools. Both habitat types were sampled with four replicate plots, showing the same vegetation structure. Strong differences were found between the concentrations and distributions of base cations in the pore water profiles from the different habitat types. The forested sites revealed higher concentrations for all base cations, but especially for Ca and Mg. Seasonality had an effect on element distributions in pore waters, but its influence was particularly strong at the forested sites. Element distributions and seasonality were caused by several interacting biological and physicochemical processes, such as plant uptake and mineralization or evaporative enrichment and dilution by rainwater. Concludingly, we draw implications for bog restoration and for the use of element ratios as criterion of mineral influence on bog waters. Our study clearly demonstrates the enhancement of base cation supply by birch encroachment, which is posing an additional burden on successful bog restoration. Additionally, the importance of an intact buffer zone around restored peat bogs is underlined. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading chemistry journals. The following PDF file contains a complete ChemInform issue, thus enabling easy electronic browsing further facilitated by electronic bookmarks. [ABSTRACT FROM AUTHOR]

The table of contents for the May 1, 2014 issue of "Helvetica Chimica Acta" is presented.

A nonequivalent, control group design was used to investigate student achievement in secondary chemistry. This study investigated the effect of process-oriented guided inquiry learning ( POGIL) in high school chemistry to reduce alternate conceptions related to the particulate nature of matter versus traditional lecture pedagogy. Data were collected from chemistry students in four large high schools and were analyzed using analysis of covariance. The results show that POGIL pedagogy, as opposed to traditional lecture pedagogy, resulted in fewer alternate conceptions related to the particulate nature of matter. Male and female students in the POGIL group posted better posttest scores than their traditional group peers. African- American and Hispanic students in the POGIL group exhibited achievement gains consistent with Caucasian and Asian students. Further studies are needed to determine the value of POGIL to address achievement gap concerns in chemistry. [ABSTRACT FROM AUTHOR]

The table of contents for the January 2014 issue of the journal "Helvetica Chimica Acta" is presented.

The table of contents for the vol. 96, No. 12 (2013) issue of "Helvetica Chimica Acta" is presented.

A subject index for the vol. 96 (2013) issue of "Helvetica Chimica Acta" is presented.

An author index for the vol. 96 (2013) issue of "Helvetica Chimica Acta" is presented.

Several abstract related to chemistry are presented which include sulfoxonium ylides, studies of reversible conjugate additions, and domino reaction.

The front cover of the journal is presented along with an overview of some articles within the issue, contact information and table of contents.

An authors index for the September 3, 2013 issue of "ChemInform" is presented.

The table of contents for the September 1, 2013 issue of "Chinese Journal of Chemistry" is presented.

An introduction is presented in which the editor discusses chemistry.

The table of contents for the August 1, 2013 issue of "Helvetica Chimica Acta" is presented.

The table of contents for the August 1, 2013 issue of "Zeitschrift für Anorganische und Allgemeine Chemie" is presented.

A author index for the 2013, 44, issue 31 of the journal "ChemInform" is presented.

A subject index for the 2013, 44, issue 31 of the journal "ChemInform" is presented.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading chemistry journals. The following PDF file contains a complete ChemInform issue, thus enabling easy electronic browsing further facilitated by electronic bookmarks. [ABSTRACT FROM AUTHOR]

Salts bearing the tetracyanopyrrolide anion (TCP) were synthesized from tetracyano-1,4-dithiin and sodium azide according to a modified synthetic protocol. The solid-state structures of HTCP, MeTCP, Me4NTCP, NaTCP, and the ionic liquid EMIMTCP (EMIM = 1-ethyl-3-methylimidazolium) are discussed for the first time. According to experimental and computational data, the TCP anion can be regarded as a pseudohalide with π bonds highly delocalized over the entire anion including the four cyano groups. The planar anion is C2 v symmetric and represents a multifunctional binary CN ligand, which is capable of forming classic coordination bonds through the lone pairs of the CN groups or the ring nitrogen atom. In addition, noncovalent interactions such as π-π interactions are found and can be used to strengthen structural and electronic communication between organic ligands. [ABSTRACT FROM AUTHOR]

Die Zukunft soll man nicht voraussehen wollen, sondern möglich machen Antoine de Saint Exupéry [ABSTRACT FROM AUTHOR]

The central goal of this study was to characterize the mental models of acids and acid strength expressed by advanced college chemistry students when engaged in prediction, explanation, and justification tasks that asked them to rank chemical compounds based on their relative acid strength. For that purpose we completed a qualitative research study involving students enrolled in different types of organic chemistry course sections at our university. Our analysis led to the identification of four distinct mental models, some of which resembled scientific models of acids and acid strength. However, the distinct models are better characterized as synthetic models that combined assumptions from one or more scientific models with intuitive beliefs about factors that determine the properties of chemical substances. For many students in our sample, mental models served more as tools for heuristic decision-making based on intuitively appealing, but many times mistaken, concept associations rather than as cognitive tools to generate explanations. Although many research participants used a single general mental model to complete all of the interview tasks, the presence of specific problem features or changes in the nature of the task (e.g., prediction vs. explanation) prompted several students to change their mental model or to add a different mental representation. Our study indicates that properly diversifying and sequencing the types of academic tasks in which students are asked to participate could better foster meaningful learning as different types of cognitive resources may be activated by different students, and thus shared, analyzed, and discussed. © 2011 Wiley Periodicals, Inc., Inc. J Res Sci Teach 48: 396-413, 2011 [ABSTRACT FROM AUTHOR]

The article provides information on a study which identified cinnamic acid derivatives as starting point for potent Pim-1 inhibitors. The fragment binders identified by the study's crystallographic fragment screen with Pim-1 are described. The results of the fragment-screening study are discussed. In addition, the binding modes of the cinnamic acid fragment hits are compared with the optimized-1 compounds originating from the high-throughput screen (HTS) approach.

In a significant work, Dobson and Doig (J Mol Biol 2003, 330, 771) illustrated protein prediction as enzymatic or not from spatial structure without resorting to alignments. They used 52 protein features and a nonlinear support vector machine model to classify more than 1000 proteins collected from the PDB with a 77% overall accuracy. The most useful features were: the secondary-structure content, the amino acid frequencies, the number of disulphide bonds, and the largest cleft size. Working on the same dataset used by D&D, in this article we reported a good and simple model, based on the Markov chain models (MCM), to classify protein 3D structures as enzymatic or not, taking into consideration the spatial structure without resorting to alignments. Here we define, for the first time, a general MCM to calculate the electrostatic potential, molecular vibrations, van der Waals (vdw) interactions, and hydrophobic interactions (HINT) and use them in comparative studies of potential fields and/or protein function prediction. The dataset is composed of 1371 proteins divided into 689 enzymes and 682 nonenzymes, all proteins were collected from the PDB. The best model we found was a linear model carried out with the linear discriminant analysis; it was able to classify 74.18% of the proteins using only two electrostatic potentials. In the work described here, we define 3D-HINT potentials (μk) and use them for the first time to derive a classifier for protein enzymes. We analyzed ROC curves, domain of applicability, parametric assumptions, desirability maps, and also tested other nonlinear artificial neural network models which did not improve the linear model. In closing, this MCM allows a fast calculation and comparison of different potentials deriving into accurate protein 3D structure-function relationships, notably simpler than the previous. © 2008 Wiley Periodicals, Inc. J Comput Chem 2009 [ABSTRACT FROM AUTHOR]

The article presents a paper about bis[2,4-diamino-5-(3,4,5-trimethoxybenzyl)pyrimidin-1-ium] DL-malate. According to the article, a 1:2 salt can be formed from racemic malic acid in which the malate compound is disordered across a centre of inversion. It says that despite of the malic acid being one of the simplest chiral dicarboxylic acids, its role in supramolecular chemistry has not been widely studied.

We quantitatively evaluated the effects of elevated concentration of ozone (O3) on growth, leaf chemistry, gas exchange, grain yield, and grain quality relative to carbon-filtered air (CF) by means of meta-analysis of published data. Our database consisted of 53 peer-reviewed studies published between 1980 and 2007, taking into account wheat type, O3 fumigation method, rooting environment, O3 concentration ([O3]), developmental stage, and additional treatments such as drought and elevated carbon dioxide concentration ([CO2]). The results suggested that elevated [O3] decreased wheat grain yield by 29% (CI: 24–34%) and aboveground biomass by 18% (CI: 13–24%), where CI is the 95% confidence interval. Even in studies where the [O3] range was between 31 and 59 ppb (average 43 ppb), there was a significant decrease in the grain yield (18%) and biomass (16%) relative to CF. Despite the increase in the grain protein content (6.8%), elevated [O3] significantly decreased the grain protein yield (−18%). Relative to CF, elevated [O3] significantly decreased photosynthetic rates (−20%), Rubisco activity (−19%), stomatal conductance (−22%), and chlorophyll content (−40%). For the whole plant, rising [O3] induced a larger decrease in belowground (−27%) biomass than in aboveground (−18%) biomass. There was no significant response difference between spring wheat and winter wheat. Wheat grown in the field showed larger decreases in leaf photosynthesis parameters than wheat grown in < 5 L pots. Open-top chamber fumigation induced a larger reduction than indoor growth chambers, when plants were exposed to elevated [O3]. The detrimental effect was progressively greater as the average daily [O3] increased, with very few exceptions. The impact of O3 increased with developmental stages, with the largest detrimental impact during grain filling. Both drought and elevated [CO2] significantly ameliorated the detrimental effects of elevated [O3], which could be explained by a significant decrease in O3 uptake resulting from decreased stomatal conductance. [ABSTRACT FROM AUTHOR]

The energy of a molecular graph G is defined as the sum of the absolute values of the eigenvalues of A(G), where A(G) is the adjacency matrix of this graph. This article characterizes conjugated chemical trees with prescribed diameter and minimal energies and presents explicit expressions of their Hosoya indices. © 2006 Wiley Periodicals, Inc. Int J Quantum Chem, 2006 [ABSTRACT FROM AUTHOR]

Information about several papers discussed at a symposium on symbolic calculation is presented. Symbolic Calculation is said to have a great impact in its application to science and engineering specifically in Chemistry and Physics. The symposium featured several papers and mathematical methods such as "Atomic and quasi-atomic properties," "Ab initio calculations of electronics structure of molecules," and "Molecular dynamics."

The present application of computer algebra is reviewed for its use in physical and quantum chemistry. After the rapid development of a great deal of numerical algorithms and codes during the past five decades, it is time that symbolic techniques become available in the chemical sciences. A careful implementation of such symbolic methods will make many tasks more efficient and will facilitate the investigation of many quantum systems. Following a brief account of the advantages and specific requests of applying computer algebra in chemistry and physics, emphasis is placed in this contribution on the BETHE program, a recently developed tool for using point-group symmetries in various fields of chemistry, including molecular spectroscopy, ligand-field theory, and material science, or even for the construction of molecular wave functions. Besides the great promise of symbolic techniques for modern research, their merits for education are pointed out, as computer algebra systems are likely to replace the traditional program languages in the undergraduate programs of chemistry and physics. © 2005 Wiley Periodicals, Inc. Int J Quantum Chem, 2006 [ABSTRACT FROM AUTHOR]

Presents several abstracts in the field of biochemistry, chemistry and physics. "Development of a Protein-Chip Containing MITF (Microphtalmia-Associated Transcription Factor) for Depigmenting Agent Screening," by E. Kwak, J. Han, J. Shin and E. Kim; "Perception of Skin Pigmentation: Melanin and Beyond," by G. N. Stamatas and N. Kollias; "Lipid Analysis of Ocular Melanosomes," by W. Ward, T. Garrett and J. D. Simon.

X-ray crystallography is the most powerful method for determining the three-dimensional structure of biological macromolecules. One of the major obstacles in the process is the production of high-quality crystals for structure determination. All too often, crystals are produced that are of poor quality and are unsuitable for diffraction studies. This review provides a compilation of post-crystallization methods that can convert poorly diffracting crystals into data-quality crystals. Protocols for annealing, dehydration, soaking and cross-linking are outlined and examples of some spectacular changes in crystal quality are provided. The protocols are easily incorporated into the structure-determination pipeline and a practical guide is provided that shows how and when to use the different post-crystallization treatments for improving crystal quality. [ABSTRACT FROM AUTHOR]

Impacts of ozone and CO2 enrichment, alone and in combination, on leaf anatomical and ultrastructural characteristics, nutrient status and cell wall chemistry in two European silver birch ( Betula pendula Roth) clones were studied. The young soil-growing trees were exposed in open-top chambers over three growing seasons to 2× ambient CO2 and/or ozone concentrations in central Finland. The trees were measured for changes in altogether 35 variables of leaf structure, nutrients and cell wall chemistry of green leaves, and 20 of the measured variables were affected by CO2 and/or O3. Elevated CO2 increased the size of chloroplasts and starch grains, number of mitochondria, P : N ratio, and contents of cell wall hemicellulose. Elevated CO2 decreased the total leaf thickness, specific leaf area, concentrations of N, K, Cu, S and Fe, and contents of cell wall α-cellulose, uronic acids, acid-soluble lignin and acetone-soluble extractives. Elevated ozone led to thinner leaves, higher palisade to spongy ratio, increased number of peroxisomes and mitochondria, reduced content of Mn, Zn, Cu, hemicellulose and uronic acids, and lower Mn : N and Zn : N ratios. In the combined exposure, interactions were antagonistic. Ultrastructural changes became more evident towards the end of the exposure. Young leaves were tolerant against ozone-caused oxidative stress, whereas oxidative H2O2 accumulation was found in older leaves. CO2 enrichment improved ozone tolerance not only through increased photosynthesis rates, but also through changes in cell wall chemistry (hemicellulose, in particular). However, nutrient imbalances due to ozone and/or CO2 may predispose the trees to other biotic and abiotic stresses. Down-regulation and up-regulation of photosynthesis under elevated CO2 through anatomical changes is discussed. [ABSTRACT FROM AUTHOR]

Discusses the utility of the ACORN as a comprehensive and efficient phasing procedure for the determination of protein structures when atomic resolution data are available. Automatic structure solution, phasing and refinement for real data at lower resolutions for proteins of various complexities.

Presents highlights of several studies on chemistry as of September 2003. Significance of the linkages between vanadosilicate clusters; Molecular strategies to study the genome; Overview of the intramolecular cyanoborylation of alkynes.

Summarizes the author's career in chemistry. Personal and education background; First encounters with the chemical field; Early scientific research; University and national scientific service; Involvement in national and international science policy.

It is generally difficult to analytically derive models describing the echo attenuation in pulsed gradient spin-echo (PGSE) experiments for even the simplest porous systems that are commonly studied--especially when the gradient pulse (d) is of finite length compared to the timescale of the diffusion measurement (D). Consequently, various levels of approximation are used to evaluate PGSE experiments. In the present paper, a conceptual view of q-space is given and two of the most common approximations, the short gradient pulse (SGP) and Gaussian phase distribution (GPD) approximations, are compared in detail with a recent matrix method, which provides "analytically" exact results giving a visual representation of the limitations of these approximations. The simulations are performed for diffusion between a pair of reflecting planes separated by a distance a. A modification that is sometimes applied to the short gradient pulse approximation in attempting to extend it to finite gradient pulses is also compared. The simulations reveal that, except when the experimental conditions closely match the requirements of the SGP and GPD simulations, the matrix method must be used in order to correctly interpret the data. [ABSTRACT FROM AUTHOR]

This article focuses on a study related to secondary school students' concepts of isotopes and allotropes. Some studies in science education described students who had not yet developed well-thought-out concepts. In some cases research has helped to understand why students propose alternatives to scientific concepts. Difficulties arise, for example, when students reason about concepts that have changed with time. In this context, the interplay between chemical terms and concepts has to be considered. Terms are labels for concepts. Chemistry textbooks reveal that the Periodic Table of Elements (PTE) is one of the basic organizing principles to which students are introduced at the secondary level. The PTE was originally developed as a two-dimensional display of elements. In this way it became a tool to predict or recall the properties of chemical elements. The PTE is one of the most important organizing principles taught in chemistry lessons.

The article offers information several periodicals related to this issue including "Chemistry: A European Journal," "ChemBioChem" and "Asian Journal of Organic Chemistry."

The article discusses the impact of an intensive in-service workshop relative to the pedagogical content knowledge growth of the novice chemical demonstrators. The workshop was designed into four training elements that are considered important to effective teacher in-servicing. This includes theory, modeling, practice and feedback. The respondents were interviewed and their responses have suggested an increased awareness of the complexity of several chemical demonstrations. Furthermore, it was pointed out that science teachers' pedagogical content knowledge in chemistry could be enhance through establishing an intensive in-service programs.

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.