bluuebunny/crossref_metadata_2025 huggingface dataset:
Some ethical issues that arise from working with families in the National Health Service
Authors: Paul M , Newns K , Creedy KV
Published: February 2007

Through a case study, this paper addresses ethical issues and dilemmas faced by a Family Therapist working in a Child and Adolescent Mental Health Service (CAMHS) in the National Health Service. When there are legal and societal obligations on parents/carers to ensure that the needs of children and young people are met within a family context, working with a young person in a health care setting oriented to the individual raises ethical dilemmas around consent. When the values of young people and their parents conflict, legal, ethical and political issues can be raised. These have implications for the duties of health care professionals and the rights, interests and autonomy of the individual young people and their parents. The importance of justice to CAMHS practitioners' ethical decision-making about when to prioritize the individual over the family, or vice versa, is emphasized.
What's in a name? Subjects, volunteers, participants and activists in clinical research
Authors: Corrigan Oonagh , Tutton Richard
Published: February 2007

The term research subject has traditionally been the preferred term in professional guidelines and academic literature to describe a patient or an individual taking part in biomedical research. In recent years, however, there has been a steady shift away from the use of the term 'research subject' in favour of 'research participant' when referring to individuals who take part by providing data to various kinds of biomedical and epidemiological research. This article critically examines this shift, reflecting on the different meanings evoked by the terms 'subject' and 'participant', as well as examining recent examples of patient activism in research. It concludes by suggesting that the wholesale unreflective adoption of the term 'participant' is inappropriate and provides instead a guide on how to determine the circumstances in which the terms subject, participant and activist should legitimately be used.
In whose best interests: who knows?
Authors: Biggs Hazel
Published: February 2007

Leslie Burke challenged the GMC guidelines on withholding and withdrawing artificial nutrition and hydration because he wanted to ensure that food and fluids were not withdrawn from him at a time when he might still be cognisant. This article reviews the case and the judgments at first instance and in the Court of Appeal. In the interests of patient autonomy it argues that the patient is best placed to decide what is in her or his best interests and that the first instance decision was an appropriate response to Mr Burke's challenge.
A messy business: qualitative research and ethical review
Authors: Dawson Angus J
Published: February 2007

This paper argues that qualitative research is both useful and necessary, as it provides an essential means of gaining a richer understanding of patients' perceptions, social processes and meanings. In their paper in this edition of Clinical Ethics, Hallowell and Lawton raise many issues relating to the way that qualitative research is treated by RECs in the UK. In this paper I discuss just three key topics stimulated by their paper: the way that methodology relates to ethics, the experience and character of the researcher, and the normative/descriptive distinction. I strongly support Hallowell and Lawton's appeal for greater communication between qualitative researchers and RECs. In other respects, I would argue that they do not go far enough. The recent review of research ethics structures and the review process provides an opportunity to move away from the present 'one size fits all' approach to ethical review. I would argue that this change could only benefit qualitative research and researchers.
Consent, trust and ethics: reflections on the findings of an interview based study with people donating blood for genetic research for research within the NHS
Authors: Busby Helen
Published: February 2007

This paper draws on findings from interviews with people donating blood for a large epidemiological study of psoriatic arthritis concerned with identifying the genetic component in the aetiology of this disease. The 27 qualitative research interviews addressed peoples' reasons for agreeing to be involved in the biomedical research project, their hopes and expectations in relation to the study, and their views about the donation of a blood sample for the genetic element of the research. The involvement of these research subjects can be characterized in terms of an investment in the future health of an imagined community, in which the NHS featured prominently.
Mental capacity, good practice and the cyclical consent process in research involving vulnerable people
Authors: Norman R , Sellman D , Warner C
Published: February 2007

The Mental Capacity Act 2005 gives statutory force to the common law principle that all adults are assumed to have capacity to make decisions unless proven otherwise. In accord with best practice, this principle places the evidential burden on researchers rather than participants and requires researchers to take account of short-term and transient understandings common among some research populations. The aim of this paper is to explore some of the implications of the MCA 2005 for researchers working with 'vulnerable' populations in health and social care settings. The Cyclical Consent Model is described and offered as a process by which researchers might develop good practice when engaged in research involving vulnerable people.
'Appropriate consent' and the use of human material for research purposes: the competent adult
Authors: McHale J V
Published: February 2007

The Human Tissue Act 2004 presents a radical change to the legal regulation of the use of human material in England and Wales. The Act presents a broad regulatory framework but much in the practical operation of the legislation will depend upon regulations to be enacted and a new Code of Practice. This article examines 'appropriate consent' for the use of human tissue for research purposes in the context of the living competent adult. It examines the provision of information as part of the consent process for the use of human materials for research purposes, the question of when consent can be withdrawn, and the controversial exception enabling the use without consent of anonymized material for research purposes where the research has been ethically approved. The paper concludes by highlighting some of the problems which may remain after the legislation comes into force.
'Exceptional circumstances' - access to low priority treatments after the Herceptin case
Authors: Newdick Christopher
Published: February 2007

What is the link between patients' rights to NHS treatment and PCTs' duties to live within their budgets? This was the issue in Rogers v Swindon PCT [2006], in which a patient had been denied trastuzamab (Herceptin®) for early-stage breast cancer. In principle, rationing is lawful and PCTs have to make hard choices about spending priorities, but they may not ignore the interests of needy patients in doing so. Rather, they must balance the 'corporate' interests of the PCT with the 'clinical' interests of individuals. One way of doing so is to adopt an Ethical Framework at the macro-level to guide NHS resource allocation, but to also recognize 'exceptional cases' at the micro-level, even if the treatment is generally considered to be a low priority. This article is primarily concerned with these micro-level cases. Patients and clinicians should know how the balance is struck. Such a system operates in Berkshire, but there is plenty of room for debate about how it should develop.
The Department of Health Review of the Human Fertilisation and Embryology Act 1990
Authors: Jones Caroline
Published: February 2007

The Department of Health's Review of the Human Fertilisation and Embryology Act 1990 is a comprehensive public consultation on the regulation of the storage and use of gametes and embryos for fertility treatment and research in the UK. The consultation considers a range of issues, including the model and scope of regulation and proposals for a single body, the Regulatory Authority for Tissue and Embryos, to replace both the Human Fertilisation and Embryology Authority and the Human Tissue Authority by April 2008. The Department of Health published its report on the consultation in March 2006, and this is discussed here in relation to both the support and criticisms of the model and scope of the current and proposed regulatory frameworks, particularly with regard to policy decision-making by bodies such as HFEA and RATE.
The UK Genethics Club: clinical ethics support for genetic services
Authors: Lucassen Anneke , Parker Michael
Published: February 2007

The UK Genethics Club was established in November 2001 in order to provide a national forum of ethics support for the profession of clinical genetics in the UK. The forum brings together health professionals, medical ethicists and lawyers and support is provided through detailed discussion of cases and sharing of good practice. Clinical genetics professionals had previously voiced concerns about making extremely difficult ethical decisions, with profound implications, in something of a vacuum. Professionals saw a lack of guidance in the area and lack of time for discussion of difficult cases as reasons for this. This paper describes the origins of the group and gives (anonymized) examples of some of the types of issues discussed.
Testing a Life-Cycle Theory of Cooperative Interorganizational Relationships: Movement Across Stages and Performance
Authors: Jap Sandy D. , Anderson Erin
Published: February 2007

This research examines the evolution of cooperative interorganizational relationships and provides an empirical test of four propositions from the DSO (Dwyer et al. 1987) life-cycle theory, and one proposition from the RV (Ring and Van de Ven 1994) theory of relationship development. Using primary data from over 1,500 resellers in a channel of distribution, we find that the mature phase is not the pinnacle of the relationship lifecycle; relationship properties (e.g., relationship harmony, overall dependence, and the reseller’s trust in the manufacturer) in this stage are no different than in the build-up phase. However, relationship properties that support relationship expansion (e.g., goal congruence and information exchange norms) reach their zenith in the build-up phase and afterwards fade into the background. All of the various relationship properties hit their nadir in the decline phase.

We also examine the development of relationships over a five-year period and consider whether movement across the stages in accordance with DSO’s theory has the same association to overall performance evaluations as movement through regressive patterns. We find that a negative history extracts a price: Movement through regressive patterns is negatively related to performance, and these relationships do not enjoy a fresh start. Instead, these movements can last for an extended period of time and are negatively related to performance outcomes during the decline phase. Thus, the development path taken appears to be related to the results achieved. Finally, we also find evidence of the critical role that individual sales representatives play in creating successful interorganizational relationships.
Strategic Technology Choice and Capacity Investment Under Demand Uncertainty
Authors: Goyal Manu , Netessine Serguei
Published: February 2007

This paper studies the impact of competition on a firm’s choice of technology (product-flexible or product-dedicated) and capacity investment decisions. Specifically, we model two firms competing with each other in two markets characterized by price-dependent and uncertain demand. The firms make three decisions in the following sequence: choice of technology (technology game), capacity investment (capacity game), and production quantities (production game). The technology and capacity games occur while the demand curve is still uncertain, and the production game is postponed until after the demand curve is revealed.

We develop best-response functions for each firm in the technology game and compare how a monopolist and a duopolist respond to a given flexibility premium. We show that the firms may respond to competition by adopting a technology which is the same as or different from what the competitor adopts. We conclude that contrary to popular belief, flexibility is not always the best response to competition—flexible and dedicated technologies may coexist in equilibrium. We demonstrate that as the difference between the two market sizes increases, a duopolist is willing to pay less for flexible technology, whereas the decision of a monopolist is not affected. Further, we find that a firm that invests in flexibility benefits from a low correlation between demands for two products, but the extent of this benefit differs depending on the competitor’s technology choice. Our results indicate that higher demand substitution may or may not promote the adoption of flexibility under competition, whereas it always facilitates the adoption of flexibility without competition. Finally, we show that contrary to intuition, as the competitor’s cost of capacity increases, the premium a flexible firm is willing to pay for flexibility decreases.
Outsourcing via Service Competition
Authors: Benjaafar Saif , Elahi Ehsan , Donohue Karen L.
Published: February 2007

We consider a single buyer who wishes to outsource a fixed demand for a manufactured good or service at a fixed price to a set of potential suppliers. We examine the value of competition as a mechanism for the buyer to elicit service quality from the suppliers. We compare two approaches the buyer could use to orchestrate this competition: (1) a supplier-allocation (SA) approach, which allocates a proportion of demand to each supplier with the proportion allocated to a supplier increasing in the quality of service the supplier promises to offer, and (2) a supplier-selection (SS) approach, which allocates all demand to one supplier with the probability that a particular supplier is selected increasing in the quality of service to which the supplier commits. In both cases, suppliers incur a cost whenever they receive a positive portion of demand, with this cost increasing in the quality of service they offer and the demand they receive. The analysis reveals that (a) a buyer could indeed orchestrate a competition among potential suppliers to promote service quality, (b) under identical allocation functions, the existence of a demand-independent service cost gives a distinct advantage to SS-type competitions, in terms of higher service quality for the buyer and higher expected profit for the supplier, (c) the relative advantage of SS versus SA depends on the magnitude of demand-independent versus demand-dependent service costs, (d) in the presence of a demand-independent service cost, a buyer should limit the number of competing suppliers under SA competition but impose no such limits under SS competition, and (e) a buyer can induce suppliers to provide higher service levels by selecting an appropriate allocation function. We illustrate the impact of these results through three example applications.
Bias and Variance Approximation in Value Function Estimates
Authors: Mannor Shie , Simester Duncan , Sun Peng , Tsitsiklis John N.
Published: February 2007

We consider a finite-state, finite-action, infinite-horizon, discounted reward Markov decision process and study the bias and variance in the value function estimates that result from empirical estimates of the model parameters. We provide closed-form approximations for the bias and variance, which can then be used to derive confidence intervals around the value function estimates. We illustrate and validate our findings using a large database describing the transaction and mailing histories for customers of a mail-order catalog firm.
Asymmetric Consumer Learning and Inventory Competition
Authors: Gaur Vishal , Park Young-Hoon
Published: February 2007

We develop a model of consumer learning and choice behavior in response to uncertain service in the marketplace. Learning could be asymmetric, that is, consumers may associate different weights with positive and negative experiences. Under this consumer model, we characterize the steady-state distribution of demand for retailers given that each retailer holds a constant in-stock service level. We then consider a noncooperative game in steady state between two retailers competing on the basis of their service levels. The demand distributions of retailers in this game are modeled using a multiplicative aggregate market-share model in which the mean demands are obtained from the steady-state results for individual purchases, but the model is simplified in other respects for tractability. Our model yields a unique pure strategy Nash equilibrium. We show that asymmetry in consumer learning has a significant impact on the optimal service levels, market shares, and profits of the retailers. When retailers have different costs, it also determines the extent of competitive advantage enjoyed by the lower-cost retailer.
Capturing Flexible Heterogeneous Utility Curves: A Bayesian Spline Approach
Authors: Kim Jin Gyo , Menzefricke Ulrich , Feinberg Fred M.
Published: February 2007

Empirical evidence suggests that decision makers often weight successive additional units of a valued attribute or monetary endowment unequally, so that their utility functions are intrinsically nonlinear or irregularly shaped. Although the analyst may impose various functional specifications exogenously, this approach is ad hoc, tedious, and reliant on various metrics to decide which specification is “best.” In this paper, we develop a method that yields individual-level, flexibly shaped utility functions for use in choice models. This flexibility at the individual level is accomplished through splines of the truncated power basis type in a general additive regression framework for latent utility. Because the number and location of spline knots are unknown, we use the birth-death process of Denison et al. (1998) and Green’s (1995) reversible jump method. We further show how exogenous constraints suggested by theory, such as monotonicity of price response, can be accommodated. Our formulation is particularly suited to estimating reaction to pricing, where individual-level monotonicity is justified theoretically and empirically, but linearity is typically not. The method is illustrated in a conjoint application in which all covariates are splined simultaneously and in three panel data sets, each of which has a single price spline. Empirical results indicate that piecewise linear splines with a modest number of knots fit these data well, substantially better than heterogeneous linear and log-linear a priori specifications. In terms of price response specifically, we find that although aggregate market-level curves can be nearly linear or log-linear, individuals often deviate widely from either. Using splines, hold-out prediction improvement over the standard heterogeneous probit model ranges from 6% to 14% in the scanner applications and exceeds 20% in the conjoint study. Moreover, “optimal” profiles in conjoint and aggregate price response curves in the scanner applications can differ markedly under the standard and the spline-based models.
An introduction to the Rasch measurement model: An example using the Hospital Anxiety and Depression Scale (HADS)
Authors: Pallant Julie F. , Tennant Alan
Published: February 2007

Objectives To demonstrate the use of Rasch analysis by assessing the appropriateness of utilizing the Hospital Anxiety and Depression Scale (HADS) total score (HADS‐14) as a measure of psychological distress.

Design Cross‐sectional, using Rasch analysis.

Methods The HADS was administered to 296 patients attending an out‐patient musculoskeletal rehabilitation program. Rasch analysis was conducted using RUMM2020 software to assess the overall fit of the model, the response scale used, individual item fit, differential item functioning (DIF) and person separation.

Results Rasch analysis supported the viability of the HADS‐14 as a measure of psychological distress. It showed good person separation, little disordering of the thresholds and no evidence of DIF. One anxiety item (item 11) showed some misfit to the model. The residuals patterned into the two subscales (anxiety and depression), but the person estimate derived from these two subscales was not statistically different to that derived from all items taken together, supporting the assumption of unidimensionality. A cut‐point of 12 on the HADS‐14 identified all cases that were classified as both anxious and depressed on the original individual HADS subscales.

Conclusions The results of Rasch analysis support the use of the HADS‐14 as a global measure of psychological distress. The study demonstrates the usefulness of Rasch analysis in assessing the psychometric properties of a scale and suggests that further use of this technique to assess the HADS‐14 in other clinical groups is warranted.
Depth Profiling by Confocal Raman Microspectroscopy: Semi-Empirical Modeling of the Raman Response
Authors: Tomba J. Pablo , Arzondo Luis M. , Pastor José M.
Published: February 2007

It has been well documented that the use of dry optics in depth profiling by confocal Raman microspectroscopy significantly distorts the laser focal volume, thus negatively affecting the spatial resolution of the measurements. In that case, the resulting in-depth confocal profile is an outcome of several contributions: the broadening of the laser spot due to instrumental factors and diffraction, the spreading of the illuminated region due to refraction of the laser beam at the sample surface, and the influence of the confocal aperture in the collection path of the laser beam. Everall and Batchelder et al. developed simple models that describe the effect of the last two factors, i.e., laser refraction and the diameter of the pinhole aperture, on the confocal profile. In this work, we compare these theoretical predictions with experimental data obtained on a series of well-defined planar interfaces, generated by contact between thin polyethylene (PE) films (35, 53, 75, and 105 μm thickness) and a much thicker poly(methyl methacrylate) (PMMA) piece. We included two refinements in the above-mentioned models: the broadening of the laser spot due to instrumental factors and diffraction and a correction for the overestimation in the decay rate of collection efficiency predicted by Batchelder et al. These refinements were included through a semi-empirical approach, consisting of independently measuring the Raman step-response in the absence of refraction by using a silicon wafer and the actual intensity decay of a thick and transparent polymer film. With these improvements, the model reliably reproduces fine features of the confocal profiles for both PE films and PMMA substrates. The results of this work show that these simple models can not only be used to assist data interpretation, but can also be used to quantitatively predict in-depth confocal profiles in experiments carried out with dry optics.
Differentiation of Mesophilic and Thermophilic Bacteria with Fourier Transform Infrared Spectroscopy
Authors: Garip Sebnem , Bozoglu Faruk , Severcan Feride
Published: February 2007

In the present study the characterization and differentiation of mesophilic and thermophilic bacteria were investigated by using Fourier transform infrared (FT-IR) spectroscopy. Our results showed significant differences between the FT-IR spectra of mesophilic and thermophilic bacteria. The protein-to-lipid ratio was significantly higher for thermophiles compared to mesophiles. The absorption intensity of the CH3 asymmetric stretching vibration was higher in thermophilic bacteria, indicating a change in the composition of the acyl chains. The higher intensity/area observed in the CH2 symmetric stretching mode at 2857 cm−1, and the CH2 bending vibration band at 1452 cm−1, indicated a higher amount of saturated lipids in thermophilic bacteria. The lipid C=O stretching vibration at 1739 cm−1, which was observed in the mesophilic group, was not observed clearly in the thermophilic group, indicating a difference in packing that is presumably due to the decreased proportion of unsaturated acyl chains in thermophilic bacteria. In addition, the carbonyl groups become hydrogen bonded and the cellular DNA content was lower in thermophilic bacteria. Moreover, in the 1000–400 cm−1 frequency region, the spectra of each bacterial species belonging to both the mesophilic and thermophilic bacterial groups, showed characteristic differences that were discriminated via dendrogram using cluster analysis. The curent study implies that FT-IR spectroscopy could be succesfuly applied for the rapid comparison of bacterial groups and species to establish either similarities or discrepencies, as well as to confirm biochemical or physiological characteristics.
Calibration of Infrared Gas Analyzers for CO2: Mathematical Model and Experimental Results
Authors: Tamas I. A. , Urquhart N. S. , Ozbun J. L.
Published: February 2007

Response curves of CO2 were determined for Beckman ir gas analyzers (models 215 and 315A) by adding small, measured amounts of CO2 to a large volume of circulating N2. We deduce a mathematical model for the response curves, estimate their parameters from our data, and comment on the role of this model in computer processing of masses of data resulting from such instruments. Close agreement between our experimental and theoretical results suggest that our model and approach should apply to similar instruments.
A Technique for the Characterization of Sorption States in Water—Cellulose Systems by Wide Line NMR
Authors: Pittman Robert A. , Tripp Verne W.
Published: February 2007

A technique is described by which the protons in water–cellulose sorption systems may be assigned to four categories. The protons are quantitatively divided into water- and cellulose-associated protons and these categories are further subdivided into interchanging and non-interchanging species. The relationships are derived on the assumption that the line narrowing observed in the NMR spectrum of celluloses on the addition of moisture is due to the rapid interchange of some of the water and cellulose protons (or their spins). The experiments were carried out at water–cellulose concentrations of about 7% on a variety of cellulose samples differing in supramolecular structure as characterized by crystalline fraction and lattice type. Data are presented which indicate that the larger the proportion of water protons involved in the interchange process, the larger the spin–spin relaxation time of those water protons not involved in the interchange. It is concluded that linewidth of the narrow component of the water–cellulose NMR signal is not related to sorption processes as simply as previously suggested.
Normal Coordinate Treatments and Calculated Thermodynamic Properties of Phosphoryl Fluorodichloride, Phosphoryl Chlorodifluoride, Thiophosphoryl Bromide, Thiophosphoryl Fluorodibromide, and Thiophosphoryl Bromodifluoride
Authors: Ziomek Joseph S. , Fillwalk Frank J. , Piotrowski Edward A.
Published: February 2007

The Raman and ir spectra of phosphoryl dichlorofluoride, phosphoryl difluorochloride, thiophosphoryl tribromide, thiophosphoryl dibromofluoride, and thiophosphoiyl difluorobromide were collected and examined for the most probable values for the wavenumbers, intensities, and depolarization factors. The data are as follows: The Raman displacements Δσ in cm−1, the relative intensities I, and the depolarization factors ρ are for POFCl2: Δσ ( I) ρ = 207(3.6)0.55, 254(1.8)6/7, 330(1)0.6, 372(3.4)6/7, 386(5.5)0.3, 547(10)0.05, 620( w)6/7, 894( w)0.45, and 1331 ( m) p; for POF2Cl: 274(10)0.65, 274 (calculated), 410(17)0.23, 424(7)6/7, 424 (calculated), 618(10)0.05, 895( m)0.1, 948( w>)6/7, and 1358( m)0.2; for PSBr3: 115(5.5)6/7, 165(4.1)0.3, 179(5)6/7, 299(10)0.05, 438( w)6/7, and 718 ( m) p; for PSFBr2:129(7)0.6, 159.5(11)6/7, 219(10)0.5, 254(4)6/7, 274(5)0.3, 377(10)0.2, 470( w)6/7, 718( m) p, and 887 ( vw) p; and for PSF2Br: 175(28)0.5, 231(3)6/7, 288(29)0.3, 298( w)6/7, 384(7)0.25, 462( w)0.1, 474(10)0.1, 711(9)0.1, 899( w)0.75, and 930( w)0.75. No published ir spectral data were found for POFCl2, POF2Cl, PSBr3, PSFBr2, and PSF2Br. Also normal coordinate treatments were conducted for POFCl2, POF2Cl, PSFBr2, and PSF2Br on the basis of the Cs model and the one for PSBr3 on the basis of the C3 v model. The results of these treatments established the above listed wavenumbers as fundamentals and lend support for 424 and 274 cm−1 bands for POF2Cl as the missing Raman bands. The F matrix elements obtained for these molecules were determined in such a way that F matrix elements common to POF3, POF2Cl, POFCl2, and POCl3 had nearly the same values and those common to PSF3, PSF2Br, PSFBr2, and PSBr3 also had nearly the same values. Finally, the values of the thermodynamic properties for these substances were computed for the ideal gaseous state using the rigid rotator harmonic oscillator approximation at 1 atm from 200 to 1000 K.
Emission Spectrometric Detection of Sample Heterogeneity
Authors: Skogerboe R. K.
Published: February 2007

A simple method which permits the detection of sample heterogeneity by emission spectroscopy is discussed using an illustrative example. Interpretation of the experimental results by classical statistical means and by a unique graphic method are compared.
Infrared Determination of Barium, Strontium, and Calcium Carbonates, Singly and Together, by the Pellet Technique
Authors: Chasan David E. , Norwitz George
Published: February 2007

Methods are proposed for the ir determination of barium, strontium, and calcium carbonates, singly or together, by the pellet technique. The sample is weighed into a tarred mortar using a semimicrobalance and is mixed with 300 mg of potassium bromide. The pellet is then formed and the peak heights are determined at the appropriate peak. The measurements for barium, strontium, and calcium carbonates are made at 693 cm−1, 704 cm−1 (or 698 cm−1), or 712 cm−1, respectively. The method for the mixed carbonates can be used down to a concentration of 5% of the minor ingredient. Sulfates and nitrates do not interfere with any of the procedures.
Low Frequency Vibrations of Molecular Crystals. XIII. CH3AsCl2, CH3AsBr2, CH3Asl2, and CD3Asl2
Authors: Durig J. R. , Jumper C. F. , Willis J. N.
Published: February 2007

The ir spectra from 4000 to 33 cm−1 have been recorded of CH3AsCl2, CH3AsBr2, CH3Asl2, and CD3Asl2. The Raman spectra of each of these compounds have been recorded and depolarization values measured for CH3AsCl2 and CH3AsBr2. The observed spectra have been successfully interpreted on the basis of a pyramidal skeletal structure of Cs symmetry. The observed values for the Teller–Redlich product rule for the assignments of the normal modes of the CH3Asl2 and CD3Asl2 molecules are in reasonable agreement with the theoretical values for both symmetry species. The As–CH3 torsional mode was tentatively assigned in the ir spectrum of solid CH3AsBr2 at 134 cm−1 and the torsional barrier calculated to be 461×30 cm−1 (1.32×0.08 kcal/mole). The low frequency bending modes of solid CH3AsI2 and CD3AsI2 have been found to show correlation field splitting and have been successfully explained in terms of the four molecules per unit cell with a space group of C2 h6.
Investigation of the Fourier Transform for Analyzing Spectroscopic Data by Computerized Learning Machines
Authors: Wangen L. E. , Frew N. M. , Isenhour T. L. , Jurs P. C.
Published: February 2007

This paper investigates the use of the fast Fourier transform as an aid in the analysis and classification of spectroscopic data. The pattern obtained after transformation is viewed as a weighted average and/or as a frequency representation of the original spectroscopic data. In pattern recognition the Fourier transform allows a different (i.e., a frequency) representation of the data which may prove more amenable to linear separation according to various categories of the patterns. The averaging property means that the information in each dimension of the original pattern is distributed over all dimensions in the pattern resulting from the Fourier transformation. Hence the arbitrary omission or loss of data points in the Fourier spectrum has less effect on the original spectrum. This property is exploited for reducing the dimensionality of the Fourier data so as to minimize data storage requirements and the time required for development of pattern classifiers for categorization of the data. Examples of applications are drawn from low resolution mass spectrometry.
Vibrational Spectra of bis-(Maleonitrile Dithiolato)Ni(ii) Anion
Authors: Rao Lakshmi P. Bhaskara , Agarwala Umesh
Published: February 2007

The in-plane normal modes of bis-(maleonitriledithiolato)Ni(ii) anion have been assigned on the basis of the normal coordinate analysis. The potential energy distribution among various internal coordinates indicates a large amount of vibrational mixing. The value of K (C–S) suggests a considerable amount of double bond character.
Observation of Hot Bands in the Raman Spectra of Cl2 Gas and CCl4 Vapor
Authors: Hochenbleicher G. , Schrötter H. W.
Published: February 2007

Hot bands were resolved in the vibrational Raman spectrum of chlorine at atmospheric pressure. The anharmonicity constant is in good agreement with the value obtained from absorption spectra. In carbon tetrachloride vapor the hot bands contributing the the ν1 band contour were investigated from 25° to 130°C.
Spectrographic Determination of Impurities in Molybdenum: Influence of a Diatomic Gaseous Reaction Product on the Arc Excitation in Argon
Authors: Morris W. F. , Worden E. F.
Published: February 2007

A spectrographic method has been developed for the determination of 24 trace elements in MoO3. The method is particularly effective for the refractory elements Nb, Ta, Zr, Ti, and V, which are difficult to determine by conventional spectrographic procedures. High sensitivity is achieved in a low amperage arc in argon as a consequence of certain thermochemical reactions which occur in the anode during the arcing process. Although it would appear that the discharge takes place in argon, in fact a small quantity of CO is evolved into the are when MoO3 is reduced in the anode. The evolution of CO changes the composition of the are gas and is essential to the ultimate vaporization and excitation of metal impurities. This paper presents time-resolved spectra, anode temperature, and arc gap voltage measurements which demonstrate the effect of CO.
Spectrographic Analysis of Cast Iron Using Fused Buttons
Authors: Cummings John P. , Hall Ronald H. , Plenzler Ronald J.
Published: February 2007

This paper presents an analytical method for the determination of minor metals in white cast iron fused buttons. This method enables the measurement of metals in cast iron with rapidity and excellent analytical results. Buttons of 40 g appear to be ideal but smaller button samples can be tolerated. The fused buttons have good homogeneity, very slight weight loss, and no significant change in composition. Metal cast spectrochemical samples are analyzed in an inert atmosphere utilizing a high voltage spark.
Infrared Band Contours and PR Separations of Fluorinated Aromatics: 1,4-Difluorobenzene
Authors: Rai M. M. , Bist H. D. , Khandelwal D. P.
Published: February 2007

The vapor phase ir spectrum of 1,4-difluorobenzene has been recorded on a Perkin–Elmer 521 spectrophotometer equipped with a 10 m variable path multiple reflection cell. The band contours have been critically studied and the PR separations of typical A-, B-, and C-type bands are reported along with the relative intensity of Q branch with respect to that of the whole band for a few typical A- and C-type contours. The observed values are compared with those computed from rotational constants using the existing semiempirical theory.
A Study of Solid-State Anion Exchange between Some p-Aminophenol Hydrohalides and Twelve Alkali Halides by Infrared Spectroscopy
Authors: Drew D. M. , van Gemert J. T.
Published: February 2007

The exchange of the anion of three hydrohalides of p-aminophenol and its N-methyl and N-benzyl derivatives has been studied by ir spectroscopy in Nujol mulls and pressed alkali halide disks. The vibrations involving the nitrogen atom are affected by the nature of the anion to an extent which makes it possible to detect the occurrence of exchange reactions. Normal grinding and pressing conditions can lead to complete exchange with the halide ion of the matrix material. The trend of exchange which is apparent for the organic compounds in sodium and potassium halides is reversed in rubidium and cesium halide matrix materials, and the presence of moisture in the grinding stage enhances the rate of reaction in most cases. Possible mechanisms are discussed in terms of the physical properties of the compounds involved, of which the main influencing factors appear to be the crystal type, lattice energies, relative ionic dimensions, and pressure induced transitions.
Solution Luminescence of Anthraquinone, Naphthoquinone, and Some Derivatives at Room Temperature
Authors: Yamanashi Bill S. , Hercules David M.
Published: February 2007

9, 10-Anthraquiuone (AQ) in an inert aliphatic solvent emits luminescence at room temperature. The emission consists of (1) solution phosphorescence and (2) delayed thermal fluorescence (DTF). We found that similar emission is observed for some AQ and naphthoquinone (NQ) derivatives. The singlet–triplet separation, Δ E1,3, was determined from the DTF–phosphorescence separation.
Spectral Background Intensity in dc Arcs as a Reference in Quantitative Analysis
Authors: Frank P. , Hahn-Weinheimer P. , Markl G.
Published: February 2007

The spectral relationships of background radiation and sample composition have been studied for synthetic glasses (2500–3500 Å) and sulfates of alkaline earths (2900–4700 Å) in gas-stabilized dc arcs (15–28 A). The influence of lithium metaborate as a spectrochemical buffer on background radiation and on evaporation of the alkaline earths has been examined. This buffer was found to improve the reproducibility of line intensities. The spectral distribution of the relative background intensity has been determined with the aid of the standard radiation of the carbon anode crater and compared with other authors' results. Electron recombination and molecule continua substantially contribute to continuous radiation. The background intensity was found to be at least as good a reference as an internal standard, particularly because it is applicable for quite a wide spectral range.
Trace Metal Determination by Crystalline Energy Transfer
Authors: Lyrle F. E. , Arnold L. H.
Published: February 2007

An expression is derived from first principles that indicates a 104 improvement in the detection limit for trace metal analyses by use of crystalline energy transfer instead of normal luminescence methods. These calculations were experimentally verified by examining a crystal comprised of tris-(2,2′-bipyridine) zinc (ii) dichloride [Zn(bipyr)3Cl2] as the host and tris-(2,2′-bipyridine) ruthenium (ii) dichloride [Ru(bipyr)3Cl2] as the emitting guest. With this system subnanogram levels of ruthenium could be measured. To verify the possibility of crystalline energy transfer quenching analysis a three component crystal was examined that had a fixed concentration of the ruthenium chelate and a varying amount of tris-(2,2′-bipyridine) iron (ii) dichloride [Fe(bipyr)3Cl2] as the quenching agent. With this system nanogram levels of iron could be measured.
Stray Light in Absorption Spectrophotometry. III. A Survey of Methods for Evaluating Stray Light Levels and Stray Light Corrections
Authors: Miranda C. , Conte P.
Published: February 2007

An experimental survey of the estimation of stray light levels and corrections has been carried out. The performance of methods requiring no special instrumentation has been evaluated and compared. A new method, as convenient as the currently used filters method and capable of yielding better results especially when large stray light corrections are required, has been established and tested.
Mercury-Vapor Detector
Authors: Joensuu Oiva I.
Published: February 2007

A simple and inexpensive accessory to an atomic-absorption spectrometer can be built which permits one to determine 1–300-ng quantities of mercury in various types of samples without any prior chemical treatment. The detector has been used with samples of sediments, rocks, coals, tissues, and waters, and is especially suited for mercury pollution studies.
The Determination of Mercury in Small Terrestrial and Nonterrestrial Rock Samples by Atomic-Absorption Spectroscopy, and the Study of Mercury Release at Elevated Temperatures
Authors: Goleb Joseph A.
Published: February 2007

An atomic-absorption method was developed for determining subnanogram amounts of mercury in 100 mg of samples and for studying the release of mercury at elevated temperatures. The rock samples were contained in a sidearm of a quartz cell, and the mercury released by heating was determined by measuring the absorption of 2537-Å light passed through the cell. For a number of terrestrial and nonterrestrial samples analyzed, the results obtained agreed within a factor of 2 with neutron activation methods. This agreement is considered satisfactory since samples are not homogeneous. For a lunar sample that contained 1.79 ppb of mercury, the precision expressed as standard error is ±0.05 ppb. The sensitivity of this method for 1% light absorption is 0.03 ng; the limit of detectability is of the order of 0.01 ng. Mercury-release patterns obtained by atomic absorption methods also were in reasonable agreement with mercury-release patterns obtained by neutron-activation methods.
An On-Line Spectrofluorimeter System for Rapid Collection of Absolute Luminescence Spectra
Authors: Wampler John E. , DeSa Richard J.
Published: February 2007

A spectrofluorimeter system has been developed which uses an on-line general purpose digital computer to both collect and correct fluorescence and luminescence spectra; no servosystems or complex analog circuitry are employed. Spectra are represented by a series of up to 500 individual data points, each of which is, in turn, the average of 16 samplings of the signal photomultiplier. The signal produced by a reference photomultiplier is also collected and used to make corrections appropriate to the type of spectra being collected. Wavelength drive is accomplished with a reversible stepping motor driven by commands from the computer; thus the wavelength position can be automatically and precisely controlled by the computer without recourse to cumbersome mechanical components. Corrections to collected spectra are made in real time on the basis of correction factors derived from fluorescence standards or a standard lamp. The complete system can collect a full spectrum (500 points) in 8 sec, average the results of any number of automatically repeated scans, and furnish the operator with both corrected and uncorrected spectra on either a wavelength or a wavenumber scale. In addition, the data can be retained on punched paper tape or presented graphically in a format acceptable for publication. Details of the system are presented with examples of its performance.
Mutant-Enriched PCR and Allele-Specific Hybridization Reaction to Detect K-ras Mutations in Stool DNA: High Prevalence in a Large Sample of Older Adults
Authors: Haug Ulrike , Hillebrand Timo , Bendzko Peter , Löw Michael , Rothenbacher Dietrich , Stegmaier Christa , Brenner Hermann
Published: February 2007

Background: Testing for mutant K-ras in stool has been proposed for the detection of pancreatic and colorectal cancer (CRC). Different analytical techniques have been developed, but studies of this biomarker in the general population are lacking. We investigated the prevalence and potential determinants of mutant K-ras in stool in a large sample of unselected older adults and assessed the association with colonoscopic findings.

Methods: In stool samples from 875 older adults (age range 50–75 years) participating in a large-scale population-based cohort study, we used mutant-enriched PCR and allele-specific hybridization reaction to analyze mutations in codons 12 and 13 of the K-ras gene. We assessed the association between mutant K-ras in stool and risk factors for gastrointestinal cancer sites, exocrine pancreatic insufficiency determined by fecal pancreas elastase 1, and colonoscopic findings.

Results: The overall prevalence of mutant K-ras in stool was 8% (95% confidence interval 6%–10%). There was a tentative association between increased fecal pancreas elastase 1 and mutant K-ras in stool (P = 0.09). Patients with advanced colorectal neoplasia diagnosed within 2 years after stool collection (24 with advanced adenomas, 7 with CRC) all tested negative.

Conclusion: The proposed assay identifies mutant K-ras in stool at a higher prevalence than has been reported for other analytical techniques. Our findings do not support the use of this assay for CRC screening, but its potential use for early detection of pancreatic cancer (in combination with other markers) requires further investigation.
Pharmacodynamic Target Attainment of Six β‐Lactams and Two Fluoroquinolones Against Pseudomonas aeruginosa, Acinetobacter baumannii, Escherichia coli, and Klebsiella Species Collected from United States Intensive Care Units in 2004
Authors: DeRyke C. Andrew , Kuti Joseph L. , Nicolau David P.
Published: February 2007

Study Objective. To determine the likelihood that antibiotic regimens achieve bactericidal pharmacodynamic exposures against common nosocomial pathogens.

Design. Pharmacodynamic Monte Carlo simulation model.

Data Source. Microbiologic data generated from isolates from the 14 centers in the United States in the 2004 Meropenem Yearly Susceptibility Test Information Collection (MYSTIC) surveillance study.

Patients. Five thousand simulated patients with infection.

Measurements and Main Results. Pharmacokinetic profiles of the patients were simulated to determine the bactericidal cumulative fraction of response (CFR) for commonly used intravenous regimens of cefepime, ceftazidime, ceftriaxone, ciprofloxacin, imipenem, levofloxacin, meropenem, and piperacillin‐tazobactam against Pseudomonas aeruginosa, Acinetobacter baumannii, Escherichia coli, and Klebsiella species. Ciprofloxacin and levofloxacin had CFRs among the lowest of all drugs against all pathogens, especially P. aeruginosa (40.4–65.5%) and A. baumannii (43.6–48.2%). The low CFR of about 78% against E. coli with these two agents was of particular concern. Among the β‐lactams, only high‐dose cefepime and ceftazidime regimens achieved CFRs of greater than 90% against P. aeruginosa, followed by cefepime 2 g every 12 hours and the carbapenems (86.3–89.7%). No regimen achieved an optimum CFR for A. baumannii. All β‐lactam regimens achieved a greater‐than‐90% likelihood of having bactericidal CFRs against Enterobacteriaceae.

Conclusion. Because of the continual evolution of resistance among gram‐negative bacteria in the United States, reevaluation of optimum dosing strategies for β‐lactam and fluoroquinolone antibiotics is necessary.