Variation in carotenoid–protein interaction in bird feathers produces novel plumage coloration

Light absorption by carotenoids is known to vary substantially with the shape or conformation of the pigment molecule induced by the molecular environment, but the role of interactions between carotenoid pigments and the proteins to which they are bound, and the resulting impact on organismal coloration, remain unclear. Here, we present a spectroscopic investigation of feathers from the brilliant red scarlet ibis (Eudocimus ruber, Threskiornithidae), the orange-red summer tanager (Piranga rubra, Cardinalidae) and the violet-purple feathers of the white-browed purpletuft (Iodopleura isabellae, Tityridae). Despite their striking differences in colour, all three of these feathers contain canthaxanthin (β,β-carotene-4,4′-dione) as their primary pigment. Reflectance and resonance Raman (rR) spectroscopy were used to investigate the induced molecular structural changes and carotenoid–protein interactions responsible for the different coloration in these plumage samples. The results demonstrate a significant variation between species in the peak frequency of the strong ethylenic vibration (ν₁) peak in the rR spectra, the most significant of which is found in I. isabellae feathers and is correlated with a red-shift in canthaxanthin absorption that results in violet reflectance. Neither polarizability of the protein environment nor planarization of the molecule upon binding can entirely account for the full extent of the colour shift. Therefore, we suggest that head-to-tail molecular alignment (i.e. J-aggregation) of the protein-bound carotenoid molecules is an additional factor.     

Managing the Public Sphere: Journalistic Construction of the Great Globalization Debate

There is little consensus on what constitutes open, deliberative media discourse. We offer a simple, measurable, and comparative model based on 3 aspects of source and issue construction in news accounts: access, recognition, and responsiveness. The model is applied to coverage of 2001–2003 World Economic Forum (WEF) meetings and protests against the organization's role in global economic policies. Both demonstrators and WEF participants were granted news access, but WEF actors were recognized more formally and given greater input in news content, including ownership claims to many activist issue positions. Journalistic deference to the WEF communication agenda limited mutual responsiveness. The journalistic process systematically managed the debate about globalization on terms that favored elites over citizen-activists.     

Binding of the catalytic subunit of protein phosphatase-1 to the ryanodine-sensitive calcium release channel protein

A number of studies have reported that the activity of the ryanodine-sensitive calcium release channel (ryanodine receptor) in the junctional sarcoplasmic reticulum of skeletal and cardiac muscle can be modulated by protein phosphorylation-dephosphorylation through activation of endogenous protein kinases and/or by addition of exogenous protein kinases and protein phosphatases. In this study, we have investigated the possibility that protein phosphatase-1 (PP1) is targeted to the junctional sarcoplasmic reticulum by the direct isolation of PP1-binding proteins on PP1-Sepharose affinity columns. The results show that the ryanodine receptor of both skeletal and cardiac muscle bind to this affinity support, and are released at supraphysiological salt concentrations in a relatively pure state. Reciprocal experiments demonstrated that PP1 binds to the immobilized muscle ryanodine receptor. The direct binding of PP1 to the ryanodine receptor was supported by the finding that tryptic fragments of the receptor were retained on PP1-Sepharose. The ability of PP1 to dephosphorylate the ryanodine receptor that was phosphorylated by protein kinase A was also demonstrated. These studies show that PP1 is targeted to the junctional sarcoplasmic reticulum by binding to the ryanodine receptor, and provide a biochemical basis for the possibility that PP1 may play a role in the regulation of calcium flux via protein phosphorylation-dephosphorylation mechanisms.     

A stable finite element simulation of convective transport

A finite element simulation of the equations of momentum and energy transport in fluids has been implemented with triangular elements. An attempt is made to single out the reasons for numerical instabilities reported by other investigators for convection–diffusion transport operations in fluid mechanics when the ratio of the convective to the diffusive terms, measured by the Reynolds and Peclét numbers, is of the order of a hundred. To this end, the equations are solved for several problems to permit a direct comparison with results of other formulations. It is shown that the appearance of instability can be delayed by a proper choice of boundary conditions, and its intensity can be reduced through the use of triangular finite elements. Results agree very well with theoretical solutions for particular test problems including flows with large convection effects, large dissipation effects and fluids with temperature dependent properties.     

Distribution of water-soluble chlorine in coals using stains and acetate peels

A technique has been developed to show the distribution of readily leachable chlorine in high chlorine coals using silver nitrate as a stain. Acetate peels may be taken of the precipitated silver chloride for closer investigation of the relations between the water-soluble chlorine and the coal lithotypes. High chlorine coals from Yorkshire Main Colliery (Barnsley Seam) and Thoresby Colliery (Top Hard Seam), showed that the durain fraction of coal will rapidly yield at least some of its water-soluble chlorine. However, vitrinite is the major host of water-soluble chlorine and the predominant component of bright coal. Bright coal shows no water-soluble chlorine component. This apparent discrepancy is explained by the size and distribution of pores and the permeability of different coal macerals. The water-soluble chlorine component is believed to be a NaCl solution held within coal pores. Pores found within the dull coal are much larger than those found in bright coal especially where the former has a high detrital mineral matter component. Bedding planes within durain bands which are coated by fossil remains or thin fusain layers are seen to be the major contributory fractions of the dull coal.     

Robust method for calculating temperature, pressure, and absorber mole fraction from broadband spectra

A robust method is described for calculating temperature, mole fraction, and pressure from measured absorption spectra (absorption coefficients versus optical frequency). The key components to the method are smoothing, differentiation, spectral axis warping, and linear least-squares fitting. The method works best when spectra span a full rotational branch of the target molecule, but in principle it works for any spectral span. The examples presented assume a measured spectrum over the 7246.4-7518.8 cm(-1) range, which encompasses the R branch of the v(1)+v(3) band of H(2)O; however, the techniques should work for most measured spectra.     

Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry of Vernonia galamensis oil

Matrix-assisted laser desorption/ionization (MALDI) time-of-flight (TOF) mass spectrometry (MS) has been used to identify eight triacylglycerols (TAG) in Vernonia galamensis oil (VO). The TAG include trivernolin, divernoloylstearoylglycerol, divernoloyloleoylglycerol, vernoloyllinoleoylstearoylglycerol, vernoloyllinoleoyloleoylglycerol, and vernoloyldilinoleoylglycerol. Samples for the MALDI/TOF/MS analysis were prepared with alpha-cyano-4-hydroxycinnamic acid (matrix) in an acetonitrile/tetrahydrofuran solvent system. A mol ratio of matrix/VO (44:1) gave reproducible composite spectra, resulting in resolutions greater than 8,000 and signal-to-noise ratios of above 1000 for the most abundant molecular species. 1,3-Dioleoyl-2-stearoylglycerol and 1,2-dioleoyl-3-palmitoylglycerol were used as calibration standards.     

Using service models for management of Internet services

As Internet services grow in complexity, Internet Service Providers (ISPs) are finding out that the ad hoc methods that they have employed thus far to monitor and diagnose their services are not sufficient to provide acceptable service quality to their subscribers. In this paper, we demonstrate how service models can he used by ISPs to effectively manage their service offerings. A service model encapsulates a human expert's knowledge of a service, its components, and its interdependencies with other services. In addition, using ongoing measurements, a service model tracks the health of the different services and their components. By traversing a service model top-down, an operator can not only assess the overall health of a service, but also easily correlate the health of all the services and service components to determine the root cause of any problems that may occur. By minimizing the time and effort needed to diagnose problems, service models enable ISP operators to efficiently resolve problems that occur in an ISP environment. Since each ISP system is unique in many respects, unique service models have to be crafted for each of the services in every ISP system. Handcrafting customized service models requires enormous effort and time on the part of a human expert, a luxury that few ISPs can afford. In this paper, we describe a methodology for constructing customized service models for a target ISP system with minimal human intervention. This methodology relies on a service model creation engine that composes a custom service model for an ISP system using a predefined service model template specification and automatically discovered information about the target ISP system. We describe a prototype implementation of this methodology and present an example of a service model obtained from a real-world ISP system. The concepts described are applicable for the management of networks and services in enterprise systems as well     

Referral of patients with pain from pancreatic cancer for neurolytic celiac plexus block

OBJECTIVE: To assess whether patients with pancreatic cancer-associated pain living near a pain control center were more likely to undergo neurolytic celiac plexus block (NCPB) than those living at a distance and to determine the rationale of physicians at our institution for referring patients for NCPB. DESIGN: We retrospectively reviewed the frequency of use of NCPB in patients with pancreatic cancer and conducted an anonymous physician survey of referral patterns for NCPB for such patients. MATERIAL AND METHODS: A prospective database of medical diagnoses and a clinical database at our institution were used to identify patients with pancreatic cancer within three geographic regions who were assessed during the inclusive years 1980 through 1989: group I ("local") = all patient with pancreatic cancer in Olmsted County, Minnesota; group II ("surrounding") and group III ("distant") = patients referred for pancreatic cancer evaluation who lived within 100 miles of our institution (excluding Olmsted County) or more than 100 miles from our institution, respectively. Medical records were retrospectively reviewed to assess the use of NCPB at any time during the course of pancreatic cancer. For the physician survey component, all medical oncologists, gastroenterologists, and general surgeons at our institution who might be responsible for the care of patients with pancreatic cancer were sent a questionnaire about their referral patterns for NCPB among patients with pancreatic cancer. RESULTS: Overall, approximately 15% of the 292 patients with pancreatic cancer studied underwent NCPB. Distance from our pain control center was not found to be associated with frequency of use of NCPB. Of the 78 physicians surveyed, 59 (76%) responded, and 35 of the responders (59%) had encountered at least 1 patient with pancreatic cancer during the preceding 12 months. In that subset of physicians, perceived barriers for referral for NCPB were limited appointment availability and need for repeating the procedure. CONCLUSION: On the basis of this study, referral patterns for NCPB in patients with pancreatic cancer do not seem to be associated with the geographic distance of a patient's residence from a pain control center. Improving appointment availability for NCPB might increase the number of patients offered this technique for control of pain.     

Relative Preferences for Paper and for Electronic Books: Implications for Reference Services,Library Instruction,and Collection Management

While electronic books (e-books) can make intellectual content more accessible, librarians are faced with uncertainties about e-book acceptance and decreasing materials budgets. What are library user attitudes toward books accessible in print or in electronic form? How might library user attitudes inform the practices of reference, instruction, and collection management librarians? Librarians at a Midwestern public university sought guidance from its users by conducting a survey examining the relative preferences for books in paper and electronic formats. Characteristics of readers and their purposes for using books were explored, as were characteristics of the formats such as accessibility, portability, and convenience.