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Research data management (RDM) is needed to assist experimental advances and data collection in the chemical sciences. Many funders require RDM because experiments are often paid for by taxpayers and the resulting data should be deposited sustainably for posterity. However, paper notebooks are still common in laboratories and research data is often stored in proprietary and/or dead-end file formats without experimental context. Data must mature beyond a mere supplement to a research paper. Electronic lab notebooks (ELN) and laboratory information management systems (LIMS) allow researchers to manage data better and they simplify research and publication. Thus, an agreement is needed on minimum information standards for data handling to support structured approaches to data reporting. As digitalization becomes part of curricular teaching, future generations of digital native chemists will embrace RDM and ELN as an organic part of their research.

A set of guiding principles for the development of a standard for FAIR management of spectroscopic data are outlined and discussed. The principles form the basis for future recommendations of IUPAC Project 2019-031-1-024 specifying a detailed data model and metadata schema for describing the contents of an “IUPAC FAIRData Collection” and the organization of digital objects within that collection. Foremost among the recommendations will be a specification for an “IUPAC FAIRData Finding Aid” that describes the collection in such a way as to optimize the findability, accessibility, interoperability, and reusability of its contents. Results of an analysis of data provided by an American Chemical Society Publications pilot study are discussed in relation to potential workflows that might be used in implementing the “IUPAC FAIRSpec” standard based on these principles.

The Chemistry Implementation Network (ChIN) is focused on supporting the FAIR Data needs of the research community regarding chemical related data. An Implementation Network is a consortium drawn from a community, in this case the chemistry discipline, committed to defining and constructing standards, materials and software in the spirit of the FAIR data principles and under the structure of the GO FAIR project. Furthermore, as a core science the ChIN has to reach beyond the chemistry community and support the use of chemical information in other disciplines. This will be facilitated through connections in the GO FAIR ecosystem of Implementation Networks. Examples of the FAIR chemical concepts that need to be supported include molecular and materials structures, chemical reactions, nomenclature and other chemical terminology and conventions. The ChIN aims to drive forward the application of the FAIR Data Principles relating to the full range of chemistry concepts that are key to the transparent and efficient communication of chemical information. Realizing the goal of FAIR chemistry data will require a culture change across the discipline. However this is best addressed once a critical mass of tools and approaches has been developed.

As IUPAC approaches its 100th anniversary, it is important to re-evaluate the mode(s) in which it operates to sustainably support the standards that are vital to the chemical enterprise–chemical naming, chemical identification, and essential terms for commerce and the community. In addition, the importance of IUPAC’s underpinning of the digital representation of chemistry in the current ‘big data’ environment cannot be underestimated. Sustainable global support for the digital use of IUPAC assets is vital to the chemical sciences.

This paper presents a formal data publishing platform for computational chemistry using semantic web technologies. This platform encapsulates computational chemistry data from a variety of packages in an Extensible Markup Language (XML) file called CSX (Common Standard for eXchange). On the basis of a Gainesville Core (GC) ontology for computational chemistry, a CSX XML file is converted into the JavaScript Object Notation for Linked Data (JSON-LD) format using an XML Stylesheet Language Transformation (XSLT) file. Ultimately the JSON-LD file is converted to subject-predicate-object triples in a Turtle (TTL) file and published on the web portal. By leveraging semantic web technologies, we are able to place computational chemistry data onto web portals as a component of a Giant Global Graph (GGG) such that computer agents, as well as individual chemists, can access the data.

Chemical Semantics, Inc. (CSI) is a new start-up devoted to bringing the Semantic Web to chemistry and biochemistry. The semantic web is referred to as Web 3.0 or alternatively the Web of Data or the Web of Meaning. It does not replace the existing World Wide Web but augments it, placing data on the web in a structured form such that the data has “meaning” and computers can understand it. CSI has created a demonstration portal for exploring this new technology, specifically at this point for data created by quantum chemistry calculations. This paper describes the basics of a semantic web portal and the fundamental technology we have used in developing it.

This paper details an approach to re-purposing scientific data as presented on a web page for the sole purpose of making the data more available for searching and integration into other websites. Data ‘scraping’ is used to extract metadata from a set of pages on the National Institute of Standards and Technology (NIST) website, clean, organize and store the metadata in a MySQL database. The metadata is then used to create a new website at the authors institution using the CakePHP framework to create a representational state transfer (REST) style application program interface (API). The processes used for website analysis, schema development, database construction, metadata scraping, REST API development, and remote data integration are discussed. Lessons learned and tips and tricks on how to get the most out of the process are also included.

Objectives The diet of tufted capuchins (Sapajus) is characterized by annual or seasonal incorporation of mechanically protected foods. Reliance on these foods raises questions about the dietary strategies of young individuals that lack strength and experience to access these resources. Previous research has demonstrated differences between the feeding competencies of adult and juvenile tufted capuchins. Here we test the hypothesis that, compared to adults, juveniles will process foods with lower toughness and elastic moduli. Materials and Methods We present data on variation in the toughness and elastic modulus of food tissues processed by Sapajus libidinosus during the dry season at Fazenda Boa Vista, Brazil. Food mechanical property data were collected using a portable universal mechanical tester. Results Results show that food tissues processed by the capuchins showed significant differences in toughness and stiffness. However, we found no relationship between an individual's age and mean or maximum food toughness or elastic modulus, indicating both juvenile and adult S. libidinosus are able to process foods of comparable properties. Discussion Although it has been suggested that juveniles avoid mechanically protected foods, age-related differences in feeding competence are not solely due to variation in food toughness or stiffness. Other factors related to food type (e.g., learning complex behavioral sequences, achieving manual dexterity, obtaining physical strength to lift stone tools, or recognizing subtle cues about food state) combined with food mechanical properties better explain variation in juvenile feeding competency. Am J Phys Anthropol, 2015. © 2015 Wiley Periodicals, Inc.

A number of websites make available spectral data for download (typically as JCAMP-DX text files) and one (ChemSpider) that also allows users to contribute spectral files. As a result, searching and retrieving such spectral data can be time consuming, and difficult to reuse if the data is compressed in the JCAMP-DX file. What is needed is a single resource that allows submission of JCAMP-DX files, export of the raw data in multiple formats, searching based on multiple chemical identifiers, and is open in terms of license and access. To address these issues a new online resource called the Open Spectral Database (OSDB) http://osdb.info/ has been developed and is now available. Built using open source tools, using open code (hosted on GitHub), providing open data, and open to community input about design and functionality, the OSDB is available for anyone to submit spectral data, making it searchable and available to the scientific community. This paper details the concept and coding, internal architecture, export formats, Representational State Transfer (REST) Application Programming Interface and options for submission of data. The OSDB website went live in November 2015. Concurrently, the GitHub repository was made available at https://github.com/stuchalk/OSDB/ , and is open for collaborators to join the project, submit issues, and contribute code. The combination of a scripting environment (PHPStorm), a PHP Framework (CakePHP), a relational database (MySQL) and a code repository (GitHub) provides all the capabilities to easily develop REST based websites for ingestion, curation and exposure of open chemical data to the community at all levels. It is hoped this software stack (or equivalent ones in other scripting languages) will be leveraged to make more chemical data available for both humans and computers.

It is well known that the toxicity of zinc (Zn) varies with water chemistry and that its bioavailability is controlled by ligand interactions and competing ions. Zn toxicity in freshwaters with varying water chemistry has been well characterized; however, far less attention has been paid to the toxicity of Zn in estuarine and marine systems. We performed experiments using two euryhaline species of killifish, Fundulus heteroclitus and Kryptolebias marmoratus, to investigate the effects of changing salinity on acute toxicity of Zn. Larvae (7- to 8-days old) of each species were exposed to various concentrations of Zn for 96 h at salinities ranging from 0 to 36 ppt and survival was monitored. As salinity increased, Zn toxicity decreased in both fish species, and at salinities above 10 ppt, K. marmoratus larvae were generally more sensitive to Zn than were those of F. heteroclitus. The protection of salinity against Zn toxicity in F. heteroclitus was further investigated to determine the role of Ca(2+). Increased Ca(2+) in freshwater protected against Zn toxicity to the same extent as did saline waters with an equal Ca(2+) concentration up to ∼200 mg/L Ca for F. heteroclitus and ∼400 mg/L Ca for K. marmoratus. These results suggest that these two species may have differing Ca(2+) requirements and/or rates of Ca(2+) uptake in water of intermediate to full-strength salinity (∼200-400 mg/L Ca(2+)) and thus differ in their sensitivity to Zn. The overall goal of this study was to better understand Zn toxicity in waters of different salinity and to generate data on acute Zn toxicity from multiple species over a range of salinities, ultimately for use in development of estuarine and marine biotic ligand models.

A new apparatus for mixing sample and reagent in flow injection analysis (FIA) is described. The continuously variable volume reactor (CVVR) replaces the conventional mixing coil in a flow injection (FI) manifold to provide mixing and dilution. A linear actuator motor allows control of the chamber volume via LabVIEW software. The chamber volume can be incremented in steps of 1 μl over the range 68–1704 μl. In addition, the chamber has an integral variable-speed stirring unit that is also under computer control. Experiments were performed to evaluate the dispersion characteristics of this new device, evaluate the volume reproducibility, and understand the mixing characteristics. Use of the chamber is shown in the determination of iron(II) in pond water, and in NIST SRM 1643d with excellent results and a detection limit of 3.7 μg/l iron(II). Advantages of the CVVR and future research activities using the device are discussed.

We present a temperature-dependent model for vapor pressure based on a feed-forward neural net and descriptors calculated using AM1 semiempirical MO-theory. This model is based on a set of 7681 measurements at various temperatures performed on 2349 molecules. We employ a 10-fold cross-validation scheme that allows us to estimate errors for individual predictions. For the training set we find a standard deviation of the error s = 0.322 and a correlation coefficient (R(2)) of 0.976. The corresponding values for the validation set are s = 0.326 and R(2) = 0.976. We thoroughly investigate the temperature-dependence of our predictions to ensure that our model behaves in a physically reasonable manner. As a further test of temperature-dependence, we also examine the accuracy of our vapor pressure model in predicting the related physical properties, the boiling point, and the enthalpy of vaporization.

We present QSPR models for normal boiling points employing a neural network approach and descriptors calculated using semiempirical MO theory (AM1 and PM3). These models are based on a data set of 6000 compounds with widely varying functionality and should therefore be applicable to a diverse range of systems. We include cross-validation by simultaneously training 10 different networks, each with different training and test sets. The predicted boiling point is given by the mean of the 10 results, and the individual error of each compound is related to the standard deviation of these predictions. For our best model we find that the standard deviation of the training error is 16.5 K for 6000 compounds and the correlation coefficient (R2) between our prediction and experiment is 0.96. We also examine the effect of different conformations and tautomerism on our calculated results. Large deviations between our predictions and experiment can generally be explained by experimental errors or problems with the semiempirical methods.

High-level ab initio calculations at the G2(MP2,SVP) level have been used to characterize the potential energy surface for ethylene loss from various [C9H11]+ ions. There is good agreement between the theoretical predictions and available experimental thermochemical data. We have characterized an alternative pathway to the phenylated cyclopropane mechanism originally proposed to explain the results of 13C-labeling studies of ethylene elimination from [PhC(CH3)2]+. This alternative mechanism is found to be consistent with experimental results of both 13C- and deuterium-labeling experiments. We also examine the mechanism for ethylene loss and label exchange for several other isomeric [C9H11]+ ions. It is found that the 13C-label exchange observed in protonated allylbenzene and some of the deuterium-labeling results for other ions can be explained by the intervention of intermediate ion–neutral complexes. Comparisons are made with previous theoretical work on related [C3H6X]+ ions (X = Ph, OH, SH and NH2). Keywords: [C9H11]+; Ethylene elimination; Label exchange; Heats of formation; Ion–neutral complex; G2(MP2,SVP)

Ab initio potential energy surfaces have been constructed and used to carry out classical simulations of the reactions of X with HOC+ and of XH+ with CO (X=Ne, Ar, and Kr). The competition between rearrangement, X+HOC+→OCH++X, and abstraction, X+HOC+→XH++CO, has been examined, and found to favor abstraction in the cases where both processes are energetically allowed. The reaction of XH+ with CO is found to produce highly vibrationally excited [CHO]+ products.

High level ab initio calculations at the G2(ZPE = MP2) level have been used to characterize the potential energy surfaces for rearrangement/fragmentation of various [C 3 H 8 N] + and [C 3 H 7 S] + isomers. In contrast to the behavior in the corresponding [C 3 H 7 O] + system, it is found that ion–neutral complexes are only of minor importance in determining the fragmentation characteristics. Either dissociation of such complexes occurs too fast due to a large barrier to their formation ([C 3 H 8 N] + system), or alternative lower-energy rearrangement routes that do not involve ion–neutral complexes are available ([C 3 H 7 S] + system). Calculated thermochemical quantities such as heats of formation and reaction barriers are found to be in reasonable agreement with experimental results. Metastable ion product abundances and results of both deuterium- and 13 C-labeling experiments are rationalized in terms of the calculated potential energy surfaces and rate constants obtained using Rice-Ramsperger-Kassel-Marcus theory.

High-level ab initio calculations using the G2** and G2(ZPE=MP2) methods have been employed to examine the effect of interaction with a range of neutral molecules (X) on the barrier to the degenerate proton-transport reactions in NNH+ (X = Ar, HF, CO, N2, H2O) and methyl cation-transport reactions in NNCH3+ (X = HF, H2, N2, HCl, H2O). It is found that the barriers to both proton and methyl cation transport are lowered from their values in the isolated ions of 182 and 152 kJ mol-1, respectively, by interaction with species having values of the proton or methyl cation affinity, respectively, lower than that of molecular nitrogen. Interaction with species that have larger values of proton or methyl cation affinities leads to a further lowering of the barrier, but transfer to the neutral molecule X becomes the more energetically favorable process in such cases. It is found that the ideal catalyst for ion transport should have an ion affinity close to but less than that of molecular nitrogen and have a large d...

High level ab initio calculations performed at the G2 level have been used to characterize the potential energy surface for rearrangement and fragmentation of [CH3CH2OCH2]+. Ion−neutral complexes play a crucial role in the lowest-energy decomposition leading to elimination of water. RRKM calculations on the G2 surface are found to give results consistent with the experimentally observed metastable ion elimination products and with the results of various deuterium- and 13C-labeling experiments. The consequences of producing [CH3CH2OCH2]+ by isomerization from [CH3CHOCH3]+ and of producing [CH3CH2CHOH]+ by isomerization from [CH3C(OH)CH3]+ in relation to the rearrangement/fragmentation behavior are examined and found to be nicely consistent with experimental observations. Experimental thermochemical quantities such as rate-limiting barriers and heats of formation are found generally to be in good agreement with calculated values.

A single line manifold incorporating three Nafion® membrane reactors has been developed for the sequential introduction of components of the mercuric thiocyanate/iron(III)/acid reagent for the determination of chloride. Nitric acid was introduced at the first reactor to give sufficient ionic strength to allow cation exchange of FeSCN2+ at the second reactor, and Hg2+ at the third reactor. The composition of the reagent was adjusted by control of the flow rates of donor and acceptor streams, reagent concentration and reactor length. Calibration over the range 0.3–25 μg ml−1 was possible, though the calibration function was curved. The manifold was used to determine chloride in river water and in pond water at concentrations of 8 and 47 μg ml−1, respectively and gave results that were not significantly different from those obtained by an EPA method. The lower range sensitivity was 0.032 absorbance μg ml−1, which compares favorably with that of other flow injection methods, but the detection limit was 300 ng ml−1, considerably higher than that can be achieved by flow injection procedures. This was due to the presence of mixing noise caused by fluctuations in reagent concentration related to pulsations in the flow in both donor and acceptor streams. Valve switching and refractive index effects were absent.

Speciated isotope dilution mass spectrometry (SIDMS) improves accuracy in the determination of chemical species in samples. It can be used to measure elements in their oxidation states as well as in organometallics or other molecular forms of species. SIDMS compensates for species transformations that occur in many of the steps of sample processing, including sampling process, storage, sample preparation and speciated measurement. It is also a diagnostic tool for identifying the most error prone steps. These combined capabilities provide a new method for establishing standard, legally defensible measurement tool in speciation analysis. Early speciation studies of Cr(VI) and Cr(III) demonstrate the unique advantages of SIDMS. Thus far, SIDMS has corrected up to 80% of the reduction of Cr(VI) to Cr(III). In theory, using SIDMS makes it possible to correct up to 90% species conversion with good precision. This paper describes how to apply the method to chromium and provides examples of the general steps.

High level ab initio calculations at the G2** level of theory have been used to examine the effect of interaction with a series of small neutral molecules (X = He, Ne, Ar, CO, HF, N2, H2O, and NH3) on the barrier for rearrangement of the isoformyl cation (HOC+) to the formyl cation (HCO+). Interaction with species (He, Ne, and Ar) whose proton affinities are less than that of CO at oxygen leads to a reduction in the barrier from the value (147 kJ mol-1) in the isolated system, but the barrier remains positive. Interaction with molecules (HF and N2) whose proton affinities lie between the proton affinities of CO at O and at C leads to the barrier becoming negative, thus allowing proton migration to take place without an overall barrier. Finally, interaction with molecules (H2O and NH3) whose proton affinities are greater than that of CO at C leads to a further lowering of the barrier; however, proton transfer to X rather than proton migration from O to C becomes energetically preferred. The most effective ...

Zinc (Zn) is an essential micronutrient to aquatic organisms, but increased concentrations may result in accumulation and toxic effects. Water chemistry is known to influence the uptake of Zn in aquatic biota; therefore, organisms inhabiting environments with variable salinities may exhibit different patterns of Zn accumulation. Likewise, metal uptake can vary in fish as a consequence of ionoregulatory status (acclimated to freshwater or saltwater). The euryhaline fish, Fundulus heteroclitus, was exposed to a control and two increased Zn concentrations (15 and 75 μg/L in moderately hard freshwater and 100 and 1,000 μg/L in 35 g/L saltwater) for 7 days. The ionic Zn concentrations were equivalent in the 75 μg/L Zn treatment in freshwater and the 100 μg/L Zn treatment in saltwater. Throughout the 7-day experiments, fish were dissected, and organ Zn distribution was quantified in the gill, intestine, liver, gall bladder, heart, and carcass. Different patterns of Zn accumulation were observed in F. heteroclitus dependent on exposure medium. Despite lower exposure concentrations, F. heteroclitus accumulated more Zn in freshwater than in saltwater in all of the organs analyzed with the exception of the carcass. In addition, there were correlations between Zn distribution and known physiological mechanisms related to osmoregulation in F. heteroclitus. Furthermore, this research suggests that F. heteroclitus are more susceptible to Zn accumulation in freshwater environments.

The use of membrane tubing for the introduction of reagents for the determination of phosphate in waters by flow injection analysis was studied. The use of membranes eliminates the need for confluence points in the design of flow injection manifolds. This increases the sensitivity of the manifold by providing a sufficient reagent excess for the reaction without diluting the sample. Methods for the introduction of acid, molybdate and hydrazine were devised for the determination of phosphate by the Molybdenum Blue method. Several membranes were examined and Nafion and Accurel (microporous polypropylene) were found to be most useful. Molybdate introduction was achieved using a supported liquid membrane (SLM). Calibration was linear and a detection limit of 12 ppb phosphate (4 ppb phosphorus) was obtained.

Three manifold configurations used in flow injection analysis were optimized for maximum sensitivity for the spectrophotometric determination of iron(II) by complexation with 1,10-phenanthroline. The parameters of flow rate(s), injected volume, manifold length and reagent concentration were studied for single, double, and reverse single line flow injection manifolds. All the manifolds produced maximum sensitivity when the dispersion coefficient (measured from the product profile) was less than 1.1. All the flow injection configurations were of comparable sensitivity, with that of the reverse configuration being slightly higher than those of the other two. The double line configuration gave the lowest detection limit (10 ng mL -1 ) because of the absence of refractive index peaks

Purpose RAF inhibitors are effective against melanomas with BRAF V600E mutations but may induce keratoacanthomas (KAs) and cutaneous squamous cell carcinomas (cSCCs). The potential of these agents to promote secondary malignancies is concerning. We analyzed cSCC and KA lesions for genetic mutations in an attempt to identify an underlying mechanism for their formation. Methods Four international centers contributed 237 KA or cSCC tumor samples from patients receiving an RAF inhibitor (either vemurafenib or sorafenib; n = 19) or immunosuppression therapy (n = 53) or tumors that developed spontaneously (n = 165). Each sample was profiled for 396 known somatic mutations across 33 cancer-related genes by using a mass spectrometric–based genotyping platform. Results Mutations were detected in 16% of tumors (38 of 237), with five tumors harboring two mutations. Mutations in TP53, CDKN2A, HRAS, KRAS, and PIK3CA were previously described in squamous cell tumors. Mutations in MYC, FGFR3, and VHL were identified for the first time. A higher frequency of activating RAS mutations was found in tumors from patients treated with an RAF inhibitor versus populations treated with a non–RAF inhibitor (21.1% v 3.2%; P < .01), although overall mutation rates between treatment groups were similar (RAF inhibitor, 21.1%; immunosuppression, 18.9%; and spontaneous, 17.6%; P = not significant). Tumor histology (KA v cSCC), tumor site (head and neck v other), patient age (≤ 70 v > 70 years), and sex had no significant impact on mutation rate or type. Conclusion Squamous cell tumors from patients treated with an RAF inhibitor have a distinct mutational profile that supports a mechanism of therapy-induced tumorigenesis in RAS-primed cells. Conceivably, cotargeting of MEK together with RAF may reduce or prevent formation of these tumors.

We present QSPR models for normal boiling points employing a neural network approach and descriptors calculated using semiempirical MO theory (AM1 and PM3). These models are based on a data set of ...

We present a temperature-dependent model for vapor pressure based on a feed-forward neural net and descriptors calculated using AM1 semiempirical MO-theory. This model is based on a set of 7681 measurements at various temperatures performed on 2349 molecules. We employ a 10-fold cross-validation scheme that allows us to estimate errors for individual predictions. For the training set we find a standard deviation of the error s = 0.322 and a correlation coefficient (R2) of 0.976. The corresponding values for the validation set are s = 0.326 and R2 = 0.976. We thoroughly investigate the temperature-dependence of our predictions to ensure that our model behaves in a physically reasonable manner. As a further test of temperature-dependence, we also examine the accuracy of our vapor pressure model in predicting the related physical properties, the boiling point, and the enthalpy of vaporization.

This paper focuses on a revision of the phenolphthalin method for cyanide analysis, with the intent of producing a robust and sensitive spectrophotometric method. Limitations of the phenolphthalin chemistry were overcome by the addition of EDTA to the reagent. The revised reagent was found to have suitably fast kinetics, a linear dynamic range of 0.01-3.0 ppm cyanide, and a detection limit of 5 ppb. The method was tested for interferences and applied to the determination of cyanide in environmental waters.

Background and Purpose— The Echoplanar Imaging Thrombolysis Evaluation Trial (EPITHET) tests the hypothesis that perfusion-weighted imaging (PWI)–diffusion-weighted imaging (DWI) mismatch predicts the response to thrombolysis. There is no accepted standardized definition of PWI-DWI mismatch. We compared common mismatch definitions in the initial 40 EPITHET patients. Methods— Raw perfusion images were used to generate maps of time to peak (TTP), mean transit time (MTT), time to peak of the impulse response (Tmax) and first moment transit time (FMT). DWI, apparent diffusion coefficient (ADC), and PWI volumes were measured with planimetric and thresholding techniques. Correlations between mismatch volume (PWI vol -DWI vol ) and DWI expansion (T2 Day 90-vol -DWI Acute-vol ) were also assessed. Results— Mean age was 68±11, time to MRI 4.5±0.7 hours, and median National Institutes of Health Stroke Scale (NIHSS) score 11 (range 4 to 23). Tmax and MTT hypoperfusion volumes were significantly lower than those calculated with TTP and FMT maps ( P R =−0.51; P =0.009). Conclusions— Deconvolution and application of PWI thresholds provide more conservative estimates of tissue at risk and decrease the frequency of mismatch accordingly. The precise definition may not be critical; however, because reperfusion alters tissue fate irrespective of mismatch.

The exceptional growth of allergies in recent years has been attributed to an increase in hygienic conditions which is linked to an under development of the immune system. This can be counteracted by the use of beneficial bacterial cultures (probiotics) which can provide a safe alternative for immune development.

The field of flow injection analysis (FIA) is growing rapidly because much applied research is being conducted around the world. This creates a great need for information dissemination across the globe to keep researchers up to date on current research trends. With the internet becoming the tool for global communication, it seems appropriate that support of the growth in FIA should be via this medium. Thus, the flow analysis database (FAD) has been developed as a central resource for bibliographic information on the area of FIA and flow analysis in general.

In an attempt to produce complete oxidation of a biological matrix, bovine liver, ozone was investigated as an additional, potentially non-contaminating, oxidizing reagent after nitric acid digestion. Experiments were carried out to determine the decomposition efficiency of residual carbon species, primarily o-, m- and p-nitrobenzoic acids (NBAs), using ozone. The NBAs were degraded by purging sample digests with ozone, while heating the solutions with microwave energy at atmospheric pressure. The effects of the degradation temperature and solution pH on the ozonation of NBAs were determined. Solid phase extraction (C 18 ) was used to extract NBAs from the acid digestate solutions prior to HPLC analysis. Reversed phase HPLC was used to determine NBA concentrations in digest solutions. After 2.5 h of purging ozone at 80 °C, 33.65 ± 3.80% o-NBA degradation, 19.39 ± 1.74% m-NBA degradation, and 26.47 ± 3.36% p-NBA degradation were obtained.

The use of a permeation tube for the production of liquid stream calibration standards in the flow injection determination of ammonia was investigated. By varying the flow rate from 0.5 to 4.0 ml min–1, calibration standards over the range 1.5–0.18 ppm could be produced. The relationship between concentration of the resulting solution and the reciprocal of the flow rate was shown to be linear. The inherent high temperature dependence of the release rate necessitated the tubes being used under thermostated conditions. The release rate was found to vary between 136 and 158 ng min–1 cm–1 over a 7 d period. Taking all sources of uncertainty into account, the 95% confidence interval for the release rate varied between 12.0 and 16.2 ng min–1 cm–1 over the same 7 d period. The device was used in a manifold for the determination of ammonia in pond water in which the method of standard additions was employed.

This paper investigates the wealth impact on aircraft manufacturers of crashes involving their aircraft. The author attempts to separate out the regulatory, tort law, and endogenous market components of these costs using stock market data. The results indicate that on average the manufacturer suffers a wealth loss of $21.3 million as the result of a fatal crash in which the structural integrity of the aircraft is at issue. The analysis suggests that not all of this amount can be attributed to regulatory or tort law mechanisms, and that market forces play a role in providing air travel safety. Copyright 1987 by Blackwell Publishing Ltd.

Earlier papers reach conflicting conclusions about the effect of concentration in the US brewing industry. This paper argues that stock market data on a more recent set of events, the intense merger activity of 1981-2, can help to resolve these differences. The results indicate that mergers between brewers, excluding the two industry leaders (Anheuser-Busch and Miller Brewing), enhance industry performance by enabling smaller brewers to exploit the scale economies enjoyed by the large ones.

Recurrent if intermittent crashes of passenger airliners usually provoke calls for wider and more stringent government regulation to ensure safety in the air. Andrew Chalk, Assistant Professor of Finance at the Southern Methodist University, Dallas, Texas, compares the poor record of state-imposed standards with the corrective influence of the movements in share prices which follow a crash.

The effects of angiotensin I (AI) and angiotensin (AII) on myocardial contractility, heart rate and coronary perfusion were observed in the isolated perfused cat heart. AII (10−11 mol) and AI (10−10 mol) both caused slowly developing sustained increases in systolic pressure of approximately 55%. There were inconsistent small increases in heart rate. Coronary perfusion was initially diminished, but later increased to above control values during the positive inotropic effect. The actions of both AI and AII were blocked by 1 sar 8 ile AII (10−9 mol). The converting enzyme inhibitors SQ 20881 (10−8 mol) and SQ 14225 (10−8 mol) blocked the effect of AI. The actions of AII or AI were not blocked by α or β adrenergic blockade or by prior treatment with reserpine.

A range of selective media was used to culture the microbial flora of the dental plaque, tongue and palate, The subjects were five young men who smoked more than twenty cigarettes a day and four who did not smoke. Neisseriae were less numerous on the mucosal surfaces of the smokers.

The May 25th, 1979 Chicago DC-10 crash provides the opportunity to test an important proposition in the theory of consumer product safety: Can market forces provide safety when products are too complex to permit buyer prepurchase inspection? This paper combines economic theory with modern finance theory to measure the cost of the crash to shareholders of the plane's manufacturer, McDonnell Douglas. The results indicate that the DC-10 crash resulted in a $200 million loss to McDonnell Douglas stockholders and that this amount exceeds any reasonable estimate of regulatory or liability costs.

At present, the domestic airline industry is in turmoil. Industry watchers have witnessed the demise of two major airlines (Braniff and Continental) followed by their subsequent rebirth, and the default of Air Florida. United has purchased the Pacific routes of Pan Am. TWA is buying Ozark, its principal competitor in its St. Louis hub. Likewise, Northwest has made a bid to buy its principal competition (Republic) in its Minneapolis/St. Paul hub.