bluuebunny/crossref_metadata_2025 huggingface dataset:
Channel Coordination in the Presence of a Dominant Retailer
Authors: Raju Jagmohan , Zhang Z. John
Published: May 2005

The retail trade today is increasingly dominated by large, centrally managed “power retailers.” In this paper, we develop a channel model in the presence of a dominant retailer to examine how a manufacturer can best coordinate such a channel.

We show that such a channel can be coordinated to the benefit of the manufacturer through either quantity discounts or a menu of two-part tariffs. Both pricing mechanisms allow the manufacturer to charge different effective prices and extract different surpluses from the two different types of retailers, even though they both have the appearance of being “fair.” However, quantity discounts and two-part tariffs are not equally efficient from the manufacturer’s perspective as a channel coordination mechanism. Therefore, the manufacturer must judiciously select its channel coordination mechanism.

Our analysis also sheds light on the role of “street money” in channel coordination. We show that such a practice can arise from a manufacturer’s effort to mete out minimum incentives to engage the dominant retailer in channel coordination. From this perspective, we derive testable implications with regard to the practice of street money.
Results on the Standard Error of the Coefficient Alpha Index of Reliability
Authors: Duhachek Adam , Coughlan Anne T. , Iacobucci Dawn
Published: May 2005

In this research, we investigate the behavior of Cronbach’s coefficient alpha and its new standard error. We systematically analyze the effects of sample size, scale length, strength of item intercorrelations, and scale dimensionality. We demonstrate the beneficial effects of sample size on alpha’s standard error and of scale length and the strengths of item intercorrelations (effects that are substitutes in their benefits) on both alpha and its standard error. Our findings also speak to this adage: Heterogeneity within the item covariance matrix (e.g., through multidimensionality or poor items) negatively impacts reliability by decreasing the precision of the estimation. We also examined the question of “equilibrium” scale length, showing the conditions for which it is optimal to add no items, or one, or multiple items to a scale. In terms of “best practices,” we recommend that researchers report a confidence interval or standard error along with the coefficient alpha point estimate.
Polarized Expression of CD74 by Gastric Epithelial Cells
Authors: Barrera Carlos A. , Beswick Ellen J. , Sierra Johanna C. , Bland David , Espejo Rosario , Mifflin Randy , Adegboyega Patrick , Crowe Sheila E. , Ernst Peter B. , Reyes Victor E.
Published: May 2005

CD74 is known as the major histocompatibility complex (MHC) class II-associated invariant chain (Ii) that regulates the cell biology and functions of MHC class II molecules. Class II MHC and Ii expression was believed to be restricted to classical antigen-presenting cells (APC); however, during inflammation, other cell types, including mucosal epithelial cells, have also been reported to express class II MHC molecules. Given the importance of Ii in the biology of class II MHC, we sought to examine the expression of Ii by gastric epithelial cells (GEC) to determine whether class II MHC molecules in these nonconventional APC cells were under the control of Ii and to further support the role that these cells may play in local immune and inflammatory responses during Helicobacter pylori infection. Thus we examined the expression of Ii on GEC from human biopsy samples and then confirmed this observation using independent methods on several GEC lines. The mRNA for Ii was detected by RT-PCR, and the various protein isoforms were also detected. Interestingly, these cells have a high level expression of surface Ii, which is polarized to the apical surface. These studies are the first to demonstrate the constitutive expression of Ii by human GEC.
Differential Expression of Laminin Isoforms in Ovarian Epithelial Carcinomas Suggesting Different Origin and Providing Tools for Differential Diagnosis
Authors: Määttä Marko , Bützow Ralf , Luostarinen Jani , Petäjäniemi Noora , Pihlajaniemi Taina , Salo Sirpa , Miyazaki Kaoru , Autio-Harmainen Helena , Virtanen Ismo
Published: May 2005

Immunohistochemistry was used to study the distribution of laminin (Ln) chains, collagen types IV (α 1/2), VII, and XVIII and Lutheran antigen (Lu) in 36 frozen ovarian carcinoma samples. Surface epithelial basement membrane (BM) of the normal ovary showed immunoreactivity for Ln α1, α3-α5, β1-3, γ1, and γ2 chains and type IV and XVIII collagens. Chains of Ln-5 (α3β3γ2) and Ln-10 (α5β1γ1) as well as type IV and XVIII collagens were found in most tumor BMs, but Ln α2 chain and type VII collagen were detected only in few tumors. Contrary to serous tumors, BMs of mucinous carcinomas showed Ln α4 chain, but not Ln α1 and β2 chains. Ln α1 chain was found in most endometrioid carcinomas, whereas chains of Ln-5 were only moderately detectable in comparison with serous and mucinous carcinomas. In the normal ovary, Lu immunoreactivity was confined to basal aspect in the ovarian epithelial cells, but in tumor specimens Lu immunostainings showed variable polarized and nonpolarized patterns. The results suggest that the three types of ovarian carcinoma have distinct differences in their Ln distribution and can be grouped based on their expression pattern. This suggests that they may have histogenetically different precursors and may help to distinguish these tumors from each other.
Immunohistochemical Distribution of Sphingosine Kinase 1 in Normal and Tumor Lung Tissue
Authors: Johnson Korey R. , Johnson Kristy Y. , Crellin Heather G. , Ogretmen Besim , Boylan Alice M. , Harley Russell A. , Obeid Lina M.
Published: May 2005

Sphingosine kinase 1 (SK1) is a key enzyme critical to the sphingolipid metabolic pathway responsible for catalyzing the formation of the bioactive lipid sphingosine-1-phosphate. SK1-mediated production of sphingosine-1-phosphate has been shown to stimulate such biological processes as cell growth, differentiation, migration, angiogenesis, and inhibition of apoptosis. In this study, cell type–specific immunolocalization of SK1 was examined in the bronchus/terminal bronchiole of the lung. Strong immunopositive staining was evident at the apical surface of pseudostratified epithelial cells of the bronchus and underlying smooth muscle cells, submucosal serous glands, immature chondrocytes, type II alveolar cells, foamy macrophages, endothelial cells of blood vessels, and neural bundles. Immunohistochemical screening for SK1 expression was performed in 25 samples of normal/tumor patient matched non–small-cell lung cancer tissue and found that 25 of 25 tumor samples (carcinoid [5 samples], squamous [10 samples], and adenocarcinoma tumors [10 samples]), exhibited overwhelmingly positive immunostaining for SK1 as compared with patient-matched normal tissue. In addition, an approximately 2-fold elevation of SK1 mRNA expression was observed in lung cancer tissue versus normal tissue, as well as in several other solid tumors. Taken together, these findings define the localization of SK1 in lung and provide clues as to how SK1 may play a role in normal lung physiology and the pathophysiology of lung cancer.
Cloning and Characterization of a Novel Animal Lectin Expressed in the Rat Sublingual Gland
Authors: Sakulsak Natthiya , Wakayama Tomohiko , Hipkaeo Wiphawi , Yamamoto Miyuki , Iseki Shoichi
Published: May 2005

We cloned a rat gene that is expressed primarily in the sublingual gland and named the predicted 503 amino-acid protein SLAMP (sublingual acinar membrane protein). SLAMP has 63% homology with human ERGIC-53-like protein, a member of the family of animal L-type lectins. Using a cDNA probe for SLAMP mRNA and rabbit antisera against SLAMP, we examined the expression and localization of SLAMP in major rat organs and tissues. With both Northern and Western blot analyses, abundant expression of SLAMP was demonstrated predominantly in the sublingual gland, with single sizes of the mRNA and protein 1.8 kb and 50 kDa, respectively, but not in other organs or tissues, including the parotid and submandibular glands. With immunohistochemistry, SLAMP was localized to the mucous acinar cells, but not to the serous demilunes or the duct system. With immunoelectron microscopy, SLAMP was localized predominantly to regions corresponding to the ER-Golgi intermediate compartment. Besides the sublingual gland, SLAMP immunore-activity was also demonstrated in mucous cells of the minor salivary glands in oral cavity and of Brunner's glands in the duodenum. These results suggested that rat SLAMP plays a specific role in the early secretory pathway of glycoproteins in specific types of mucous cells.
Immunohistochemical Localization of Monoamine Oxidase Type B in Pancreatic Islets of the Rat
Authors: Huang Yu-Hong , Ito Akio , Arai Ryohachi
Published: May 2005

Monoamine oxidase (MAO) is regarded as a mitochondrial enzyme. This enzyme localizes on the outer membrane of mitochondria. There are two kinds of MAO isozymes, MAO type A (MAOA) and type B (MAOB). Previous studies have shown that MAOB activity is found in the pancreatic islets. This activity in the islets is increased by the fasting-induced decrease of plasma glucose level. Islet B cells contain monoamines in their secretory granules. These monoamines inhibit the secretion of insulin from the B cells. MAOB is active in degrading monoamines. Therefore, MAOB may influence the insulin-secretory process by regulating the stores of monoamines in the B cells. However, it has not been determined whether MAOB is localized on B cells or other cell types of the islets. In the present study, we used both double-labeling immunofluorescence histochemical and electron microscopic immunohistochemical methods to examine the subcellular localization of MAOB in rat pancreatic islets. MAOB was found in the mitochondrial outer membranes of glucagon-secreting cells (A cells), insulin-secreting cells (B cells), and some pancreatic polypeptide (PP)-secreting cells (PP cells), but no MAOB was found in somato-statin-secreting cells (D cells), nor in certain other PP cells. There were two kinds of mitochondria in pancreatic islet B cells: one contains MAOB on their outer membranes, but a substantial proportion of them lack this enzyme. Our findings indicate that pancreatic islet B cells contain MAOB on their mitochondrial outer membranes, and this enzyme may be involved in the regulation of monoamine levels and insulin secretion in the B cells.
Elongation of Peroxisomes as an Indicator for Efficient Dynamin-like Protein 1 Knock Down in Mammalian Cells
Authors: Boll Antje , Schrader Michael
Published: May 2005

RNA interference has become a valuable tool to identify and investigate proteins involved in the formation of peroxisomes. We demonstrate that the elongation of peroxisomes serves as an excellent indicator for efficient knock down of dynamin-like protein 1 (DLP1) in mammalian cells. We took advantage of the silencing-dependent morphological changes of peroxisomes to compare different transfection methods and show that a single transfection of DLP1 siRNA by electroporation is sufficient to effectively silence DLP1. We present a fast, easy, and convenient protocol for efficient gene silencing in a large number of cells, which can be used for quantitative and biochemical studies.
Assessment of Human Pancreatic Islet Architecture and Composition by Laser Scanning Confocal Microscopy
Authors: Brissova Marcela , Fowler Michael J. , Nicholson Wendell E. , Chu Anita , Hirshberg Boaz , Harlan David M. , Powers Alvin C.
Published: May 2005

The recent success of pancreatic islet transplantation has generated considerable enthusiasm. To better understand the quality and characteristics of human islets used for transplantation, we performed detailed analysis of islet architecture and composition using confocal laser scanning microscopy. Human islets from six separate isolations provided by three different islet isolation centers were compared with isolated mouse and non-human primate islets. As expected from histological sections of murine pancreas, in isolated murine islets α and δ cells resided at the periphery of the β-cell core. However, human islets were markedly different in that α, β, and δ cells were dispersed throughout the islet. This pattern of cell distribution was present in all human islet preparations and islets of various sizes and was also seen in histological sections of human pancreas. The architecture of isolated non-human primate islets was very similar to that of human islets. Using an image analysis program, we calculated the volume of α, β, and δ cells. In contrast to murine islets, we found that populations of islet cell types varied considerably in human islets. The results indicate that human islets not only are quite heterogeneous in terms of cell composition but also have a substantially different architecture from widely studied murine islets.
Modeling high‐pressure wax formation in petroleum fluids
Authors: Sansot Jean‐Marc , Pauly Jérôme , Daridon Jean‐Luc , Coutinho Joao A. P.
Published: May 2005

A procedure is presented for the simultaneous prediction of fluid–fluid and solid–fluid equilibrium of light gases/heavy hydrocarbons systems under pressure. The objective of this work is to simplify the predictive approach previously proposed by the authors, making it more useful and accessible to users at the petroleum industry. The main modification with respect to the complex LCVM (linear combination of Huron–Vial and Michelsen) mixing rule that was previously used for the attractive term “a” of the equation of state (EOS). To avoid the use of a group contribution method, which is difficult to bring into play with real fluids, the LCVM mixing rule is here replaced by the classical quadratic van der Walls one‐fluid mixing rule. The deviation that using this mixing rule introduces into the gamma–phi approach is cancelled by a new parameter ξ, introduced in the calculation of the solid‐phase activity coefficient. This procedure was tested for a large range of multicomponent systems where the parameter ξ was fitted to match the wax appearance temperature (WAT) at atmospheric pressure. From the ξ values obtained a correlation relating the parameter ξ to the carbon number in the heavy fraction was developed, allowing a prediction of wax formation in petroleum fluids. It is shown that this approach can successfully be applied to the prediction of wax formation at high pressure for live oils. © 2005 American Institute of Chemical Engineers AIChE J, 2005
A novel EOS that combines van der Waals and Dieterici potentials
Authors: Polishuk Ilya , Vera Juan H.
Published: May 2005

A novel approach is proposed for solving the problem of the overestimation of the liquid–liquid equilibrium (LLE) range in mixtures typically associated with the use of equations of state (EOS) of the van der Waals type. This approach modifies the internal EOS structure by combining the van der Waals and the Dieterici forms. It advantageously uses the drawback of the Dieterici form, which strongly underestimates the LLE range. Thus, the new EOS is capable of generating an appropriate balance for the representation of vapor–liquid equilibria (VLE) and LLE critical data and therefore represents a major improvement in comparison with typical van der Waals–type EOSs. In addition, it gives accurate representation of the Joule–Thomson inversion curve and predicts critical data for nonpolar mixtures without any binary parameters. For polar systems, the novel EOS predicts critical data for complete homologous series of mixtures using a pair of binary parameters evaluated from a single system. © 2005 American Institute of Chemical Engineers AIChE J, 2005
Direct determination of energy dissipation in stirred vessels with two‐point LDA
Authors: Ducci A. , Yianneskis M.
Published: May 2005

The ensemble‐averaged kinetic energy viscous dissipation rate was determined with a multipoint LDA technique in a vessel stirred by a Rushton turbine. Nine out of the total of 12 mean squared velocity gradients constituting the dissipation rate were directly measured in the impeller stream, and the deviation of the flow from local isotropy was investigated. The dissipation rate normalized with N3D2, where N and D are the impeller rotational speed and the impeller diameter, respectively, was found to be approximately constant for Reynolds numbers of 20,000–40,000, whereas the fluctuating gradients were found to vary significantly, by up to three times the ensemble‐averaged values, with blade angular position. The ensemble‐averaged dissipation rate values were also assessed through a local turbulence kinetic energy balance. © 2005 American Institute of Chemical Engineers AIChE J, 2005
Extended statistical associating fluid theory (SAFT) equations of state for dipolar fluids
Authors: Karakatsani Eirini K. , Spyriouni Theodora , Economou Ioannis G.
Published: May 2005

Polar forces have a considerable effect on the thermodynamic and phase equilibrium properties of pure and mixture fluids. In this work, the statistical associating fluid theory (SAFT) and perturbed chain–SAFT (PC‐SAFT) are extended to explicitly account for dipole–dipole interactions. A recently proposed perturbation theory for pure dipolar fluids is incorporated in both models and further extended to mixtures. Polar SAFT (PSAFT) and PC‐polar SAFT (PC‐PSAFT) are applied to alcohols, ketones, water, and other dipolar fluids. Vapor pressure and saturated liquid densities are correlated over a wide temperature range from low temperature up to very near the critical point. Critical constants, second virial coefficients, and monomer fraction predictions are reported. Furthermore, the models are applied to correlate the vapor–liquid equilibria of binary mixtures. A temperature‐independent binary interaction parameter is regressed from experimental data. Finally, model predictions for representative polar ternary mixtures are presented. In all cases, very good agreement with experimental data is obtained. © 2005 American Institute of Chemical Engineers AIChE J, 2005
Hydrogen generation in a reverse‐flow microreactor: 1. Model formulation and scaling
Authors: Kaisare Niket S. , Lee Jay H. , Fedorov Andrei G.
Published: May 2005

A 1‐D model for methane partial oxidation in a tubular microreactor is considered. This work is motivated by a recent report by Kikas et al. that experimentally demonstrated the possibility of autothermal generation of hydrogen by partial oxidation of methane in a tubular microreactor. The reactor consists of four cylindrical channels, each 500 microns in diameter, containing Pt/13%–Rh catalyst. Autothermal generation of hydrogen was possible in both unidirectional (UD) and reverse‐flow (RF) operations of the reactor, with the RF operation providing better hydrogen yield and lower temperatures than those of the UD operation. Critical comparison of methane oxidation and reforming kinetics from the literature is performed. An analysis of the timescales of individual processes within the reactor is presented to gain fundamental insight into the reactor operation. Finally, the effect of radiation heat transfer is also considered, and it is found to play an important role for a shorter‐size reactor. © 2005 American Institute of Chemical Engineers AIChE J, 2005
Hydrogen generation in a reverse‐flow microreactor: 2. Simulation and analysis
Authors: Kaisare Niket S. , Lee Jay H. , Fedorov Andrei G.
Published: May 2005

The second part in this series presents parametric simulation and sensitivity analysis of methane partial oxidation in a microreactor operated with periodic flow reversal. The reverse‐flow (RF) operation provides up to a 5% increase in the hydrogen yield compared to that of the unidirectional (UD) operation. The effect of varying the inlet CH4:O2 feed ratio, the inlet velocity, and the inlet gas temperature is studied. The optimal feed ratio is found to be CH4:O2 = 1.15:1 with the feed at ambient room temperature. The effects of varying the reactor length and heat losses to the ambient are also investigated. In both these cases, the performance of the UD operation degrades significantly, whereas the performance of the RF operation is more robust to the variations in reactor size and heat losses. The issue of choosing the optimal switching time is also addressed. Switching the input and output ports near the natural timescale of reaction heat release is shown to provide the optimum yield. Through these results, design and operation guidelines based on simple timescale analysis have emerged. © 2005 American Institute of Chemical Engineers AIChE J, 2005
New developments in the behavioral ecology and conservation of ruffed lemurs (Varecia)
Authors: Vasey Natalie
Published: May 2005

The papers in this issue were presented at a symposium during the 25th Annual Meeting of the American Society of Primatologists held in Oklahoma City, Oklahoma, in June 2002. This symposium brought together many of the scientists who have contributed to our knowledge of ruffed lemur ecology, behavior, and conservation in the past decade. One objective was to share and compare key findings about ruffed lemurs (Varecia) resulting from long‐term field studies at various sites in Madagascar. A second objective was to cross‐fertilize work being done in the wild with that being done in captivity, with the aim of advancing a common conservation mission for this critically endangered genus. Varecia is a prime candidate for synthetic assessments such as these because it has now been studied in both the northern and southern reaches of its geographic range, and has also been the focus of a captive‐to‐wild reinforcement project. The papers in this issue contribute to 1) the establishment of reference ranges for a suite of physiological parameters in healthy wild Varecia populations; 2) environmental enrichment aimed at preserving species‐typical behaviors in captivity; 3) an understanding of how forest structure, floristic composition, and fruiting phenology in areas with differing disturbance histories correlate with the natural occurrence and abundance of Varecia; 4) primary knowledge concerning dominance relations between the sexes and group leadership in wild Varecia; and 5) primary knowledge concerning how wild Varecia, with their unusual reproductive pattern and heavy reliance on fruit, modulate their activity budgets seasonally and in tandem with reproductive stages. Am. J. Primatol. 66:1–6, 2005. © 2005 Wiley‐Liss, Inc.
Activity budgets and activity rhythms in red ruffed lemurs (Varecia rubra) on the Masoala Peninsula, Madagascar: seasonality and reproductive energetics
Authors: Vasey Natalie
Published: May 2005

The activity budgets and daily activity rhythms of Varecia rubra were examined over an annual cycle according to season and reproductive stage. Given the relatively high reproductive costs and patchy food resources of this species, I predicted that V. rubra would 1) travel less and feed more during seasonal resource scarcity in an attempt to maintain energy balance, and 2) show sex differences in activity budgets due to differing reproductive investment. Contrary to the first prediction, V. rubra does not increase feeding time during seasonal food scarcity; rather, females feed for a consistent amount of time in every season, whereas males feed most during the resource‐rich, hot dry season. The results are consistent with other predictions: V. rubra travels less in the resource‐scarce cold rainy season, and there are some pronounced sex differences, with females feeding more and resting less than males in every season and in every reproductive stage except gestation. However, there are also some provocative similarities between the sexes when activity budgets are examined by reproductive stage. During gestation, female and male activity budgets do not differ and appear geared toward energy accumulation: both sexes feed and rest extensively and travel least during this stage. During lactation, activity budgets are geared toward high energy expenditure: both sexes travel most and in equal measure, and rest least, although it remains the case that females feed more and rest less than males. These similarities between female and male activity budgets appear related to cooperative infant care. The high energetic costs of reproduction in V. rubra females may require that they allot more time to feeding year round, and that their overall activity budget be more directly responsive to seasonal climate change, seasonal food distribution, and reproductive schedules. Am. J. Primatol. 66:23–44, 2005.
Effects of forest structure and composition on food availability for Varecia variegata at Ranomafana National Park, Madagascar
Authors: Balko Elizabeth A. , Brian Underwood H.
Published: May 2005

We present a summary of a long‐term field study that examined the effects of forest disturbance on the availability of palatable fruit and its utilization by V. variegata. Forest structure and tree species composition were measured in three adjacent study areas, with different histories of disturbance, in Ranomafana National Park (RNP), Madagascar. V. variegata abundance was monitored by frequent encounters with resident groups and periodic censuses conducted along trails. Finally, the abundance of mature fruit in species used by V. variegata was scored monthly at representative trees at several locations. V. variegata abundance was most consistent in the least anthropogenically disturbed site, while no established lemur groups were observed in the heavily logged site for over a decade post‐harvest. Lemur abundance was variable in the selectively logged site. The presence of select food trees, particularly specimens with voluminous crowns capable of producing abundant fruit crops, appears to be key to the establishment and expansion of V. variegata groups. Our analysis of year‐long fruit utilization revealed a high degree of preference for several species of trees. Two species exhibited mature fruit in a low percentage of stems but were available for a protracted period of time, while two additional species showed high intraspecific fruiting synchrony and were available for a shorter period of time. These contrasting phenologies, rather than the individual tree species, may be most important to V. variegata due to their coincident timing of fruit maturation with key lemur life‐history events. Any disturbance–natural or anthropogenic–that disrupts the phenology cycles of food trees has the potential to impact lemur abundance and dispersion. Intense disturbances, such as heavy logging or severe cyclones, have long‐lasting impacts on fruit production, while selective logging or moderate cyclonic windthrow cause more transient impacts. V. variegata is adapted to deal with an intrinsically erratic food supply by virtue of its reproductive biology and social behavior. Am. J. Primatol. 66:45–70, 2005. © 2005 Wiley‐Liss, Inc.
Preliminary biomedical evaluation of wild ruffed lemurs (Varecia variegata and V. rubra)
Authors: Junge Randall E. , Louis Edward E.
Published: May 2005

Complete medical examinations were performed on 11 wild ruffed lemurs (Varecia variegata and V. rubra) from three sites in Madagascar. Each animal received a complete physical examination, several physiological parameters were analyzed (complete blood count, serum biochemical profile, and fecal bacterial culture), and the animals were examined for endo‐, ecto‐, and hemoparasites. Additional tests were performed as samples were available, including fat‐soluble vitamin analysis, trace mineral analysis, toxoplasmosis serology, and viral serology. We found that the ruffed lemurs were in good health, harbored a low endoparasite load, and frequently had external parasites (e.g., ticks (Haemophysalis lemuris)). Statistically significant differences between captive and wild lemurs were found for the following serum biochemical and blood count parameters: alanine aminotransferase (ALT), total protein (TP), albumin, blood urea nitrogen, cholesterol, glucose, amylase, band neutrophil count, and eosinophil count. Low blood urea nitrogen (BUN) and serum cholesterol values in wild lemurs (compared to those of North American captive zoo ruffed lemurs) may suggest differences between diets in the wild and captivity. Am. J. Primatol. 66:85–94, 2005. © 2005 Wiley‐Liss, Inc.
Conceptual framework for tasks in information studies
Authors: Byström Katriina , Hansen Preben
Published: May 2005

Today information‐intensive work tasks in professional settings involve highly dynamic information utilization in which information seeking and searching tasks are taking a more central role. This article considers the concept of task in the context of information studies in order to provide a definitional clarity for task‐based information seeking and retrieval studies. We identify (1) the central task levels as well as (2) the kinds of dimensions connected to the levels from the perspective of information studies. The analysis is aimed to serve as a conceptual starting point for empirical studies in the research area. The focus is on some central aspects of tasks that are recognized within information studies as well as related research areas (e.g., organizational studies). We define two levels of information‐related subtasks: information seeking tasks and information search tasks. Information retrieval tasks are explicitly considered as a specific type of information search task. We describe differences and connections between these task levels. Finally, the implications of the proposed conceptual framework for information studies are discussed.
Role‐related library use by local union officials
Authors: Chaplan Margaret A. , Hertenstein Edward J.
Published: May 2005

A questionnaire was distributed to local union officials in Illinois in order to determine the officials' use of various types of libraries, their satisfaction with their experience in using the libraries, the problems they encountered in library use, and their opinion of various ways in which libraries might be made more useful to them. They were also asked whether they had had training in how to find information. Respondents to the survey used more than one type of library, and their union role had an impact on which type they were likely to use. They used different types of libraries to find different types of information. In general they were satisfied with their library experience, but they found library collections inadequate for their needs. Respondents who had had training in how to find information appeared to use libraries more but differed little in the frequency or types of problems encountered from those who had no training. When asked their opinion on various suggestions for improving library service to local union officials, they preferred measures that gave greater emphasis to increasing labor materials in library collections. The findings of this study, combined with those of our earlier study (Chaplan & Hertenstein, 2002), suggest that an information seeking model developed by Wilkinson (2001) may be useful in explaining union officials' information seeking behavior.
Thermophysiological responses of human volunteers to whole body RF exposure at 220 MHz
Authors: Adair Eleanor R. , Blick Dennis W. , Allen Stewart J. , Mylacraine Kevin S. , Ziriax John M. , Scholl Dennis M.
Published: May 2005

Since 1994, our research has demonstrated how thermophysiological responses are mobilized in human volunteers exposed to three radio frequencies, 100, 450, and 2450 MHz. A significant gap in this frequency range is now filled by the present study, conducted at 220 MHz. Thermoregulatory responses of heat loss and heat production were measured in six adult volunteers (five males, one female, aged 24–63 years) during 45 min whole body dorsal exposures to 220 MHz radio frequency (RF) energy. Three power densities (PD = 9, 12, and 15 mW/cm2 [1 mW/cm2 = 10 W/m2], whole body average normalized specific absorption rate [SAR] = 0.045 [W/kg]/[mW/cm2] = 0.0045 [W/kg]/[W/m2]) were tested at each of three ambient temperatures (Ta = 24, 28, and 31 °C) plus Ta controls (no RF). Measured responses included esophageal (Tesoph) and seven skin temperatures (Tsk), metabolic rate (M), local sweat rate, and local skin blood flow (SkBF). Derived measures included heart rate (HR), respiration rate, and total evaporative water loss (EWL). Finite difference‐time domain (FDTD) modeling of a seated 70 kg human exposed to 220 MHz predicted six localized ‘hot spots’ at which local temperatures were also measured. No changes in M occurred under any test condition, while Tesoph showed small changes (≤0.35 °C) but never exceeded 37.3 °C. As with similar exposures at 100 MHz, local Tsk changed little and modest increases in SkBF were recorded. At 220 MHz, vigorous sweating occurred at PD = 12 and 15 mW/cm2, with sweating levels higher than those observed for equivalent PD at 100 MHz. Predicted ‘hot spots’ were confirmed by local temperature measurements. The FDTD model showed the local SAR in deep neural tissues that harbor temperature‐sensitive neurons (e.g., brainstem, spinal cord) to be greater at 220 than at 100 MHz. Human exposure at both 220 and 100 MHz results in far less skin heating than occurs during exposure at 450 MHz. However, the exposed subjects thermoregulate efficiently because of increased heat loss responses, particularly sweating. It is clear that these responses are controlled by neural signals from thermosensors deep in the brainstem and spinal cord, rather than those in the skin. Bioelectromagnetics 26:448–461, 2005. Published 2005 Wiley‐Liss, Inc.
Identification of genes affecting lycopene accumulation in Escherichia coli using a shot‐gun method
Authors: Kang Min Jung , Lee Young Mi , Yoon Sang Hwal , Kim Jung Heon , Ock So Won , Jung Kyung Hwa , Shin Yong Chul , Keasling Jay D. , Kim Seon Won
Published: May 2005

Genes enhancing lycopene production in Escherichia coli were identified through colorimetric screening of shot‐gun library clones constructed with E. coli chromosomal DNA. These E. coli cells had been engineered to produce lycopene, a red‐colored carotenoid, which enabled screening for genes that enhance lycopene production. Six clones with enhanced lycopene production were isolated. Among 13 genes in these clones, dxs, appY, crl, and rpoS were found to be involved in enhanced lycopene production. While dxs and rpoS have been already reported to enhance lycopene production, appY and crl have not. DXP (1‐deoxy‐D‐xylulose‐5‐phosphate) synthase is encoded by dxs and participates in the rate‐limiting step in the synthesis of isopentenyl pyrophosphate (IPP), a building block of lycopene. Sigma S factor, encoded by rpoS, regulates transcription of genes induced at the stationary phase. The appY and crl genes encode transcriptional regulators related to anaerobic energy metabolism and the formation of curli surface fibers, respectively. E. coli harboring appY plasmids produced 2.8 mg lycopene/g dry cell weight (DCW), the same amount obtained with dxs despite the fact that appY is not directly involved in the lycopene synthesis pathway. The co‐expression of appY, crl, and rpoS with dxs synergistically enhanced lycopene production. The co‐expression of appY with dxs produced eight times the amount of lycopene (4.7 mg/g DCW) that was produced without expression of both genes (0.6 mg/g DCW). © 2005 Wiley Periodicals, Inc.
Rectal intussusception in symptomatic patients is different from that in asymptomatic volunteers
Authors: Dvorkin L S , Gladman M A , Epstein J , Scott S M , Williams N S , Lunniss P J
Published: May 2005

Background

Rectal intussusception is a common finding at evacuation proctography in both symptomatic and asymptomatic individuals. Little information exists, however, as to whether intussusception morphology differs between patients with evacuatory dysfunction and healthy volunteers.

Methods

Thirty patients (19 women; median age 44 (range 21–76) years) with disordered rectal evacuation, in whom an isolated intussusception was seen on proctography, were studied. Various morphological parameters were measured, and compared with those from 11 asymptomatic controls (six women; median age 30 (range 24–38) years) found, from 31 volunteers, to have rectal intussusception. Intussusceptum thickness greater than 3 mm was designated as full thickness. Intussuscepta impeding evacuation were deemed to be occluding.

Results

Twenty-two patients had full-thickness intussusception, compared with two controls (P = 0·003). Intussusceptum thickness was significantly greater in the symptomatic group (anterior component: P = 0·004; posterior: P = 0·011). Twenty patients in the symptomatic group, but only three subjects in the control group, had a mechanically occluding intussusception (P = 0·043), although only three patients demonstrated evacuatory dynamics outside the normal range.

Conclusion

Rectal intussusception in patients with evacuatory dysfunction is more advanced morphologically than that seen in asymptomatic controls; it is predominantly full thickness in patients and mucosal in controls. However, caution is required when selecting patients for intervention based solely on radiological findings.
Randomized clinical trial of laparoscopic Nissen fundoplication compared with proton-pump inhibitors for treatment of chronic gastro-oesophageal reflux
Authors: Mahon D , Rhodes M , Decadt B , Hindmarsh A , Lowndes R , Beckingham I , Koo B , Newcombe R G
Published: May 2005

Background

Both laparoscopic Nissen fundoplication (LNF) and proton-pump inhibitor (PPI) therapy are established in the treatment of gastro-oesophageal reflux disease (GORD). The aim of this study was to compare these two treatments in a randomized clinical trial.

Methods

Between July 1997 and August 2001, 340 patients with a history of GORD for at least 6 months were investigated by endoscopy, 24-h pH monitoring and manometry. Of these, 217 were randomized, 109 to LNF and 108 to PPI therapy. The two groups were well matched for age, sex, weight and severity of reflux. Twenty-four-hour pH monitoring and manometry were performed 3 months after treatment, and quality of life was assessed in both groups using the Psychological General Well-being Index and the Gastrointestinal Symptom Rating Scale at 3 and 12 months after treatment.

Results

At 3 months there was an improvement in lower oesophageal sphincter pressure from 6·3 to 17·2 mmHg in the LNF group but no change in the PPI group (8·1 and 7·9 mmHg before and after treatment respectively) (P < 0·001). The mean DeMeester acid exposure score improved from 42·7 to 8·6 (P < 0·001) in the LNF group and from 36·9 to 17·7 in the PPI group (P < 0·001). The mean gastrointestinal symptom and general well-being scores improved from 31·7 and 95·4 respectively before treatment to 37·0 and 106·2 at 12 months after LNF, compared with changes from 34·3 and 98·5 to 35·0 and 100·4 respectively in the PPI group. The differences in both of these scores were significant between the two groups at 12 months (P = 0·003).

Conclusion

LNF leads to significantly less acid exposure of the lower oesophagus at 3 months and significantly greater improvements in both gastrointestinal and general well-being after 12 months compared with PPI treatment.
Surgery for non-localized bronchiectasis
Authors: Schneiter D , Meyer N , Lardinois D , Korom S , Kestenholz P , Weder W
Published: May 2005

Background

Resection for localized bronchiectasis is a well established therapy. However, there is little information on the role of surgery in non-localized bronchiectasis.

Methods

Between January 1992 and April 2001, 55 patients without cystic fibrosis underwent resection. Forty-eight patients (mean age 45 (range 23–74) years; 32 women) were available for long-term follow-up. Twenty-five patients underwent resection for localized disease (group 1) and 23 had bronchiectasis in at least two different lobes (group 2).

Results

Thirty-one of the 48 patients were treated by Video Assisted Thoracoscopic Surgery (VATS) resection. There was no 30-day mortality. Mean duration of hospital stay was 10·9 (range 6–31) days in group 1 and 11·1 (range 5–19) days in group 2. Three of 25 patients in group 1 required reoperation. Only minor complications occurred in group 2 (three patients). Mean follow-up for both groups was 37 (range 6–97) months. Twenty-three of 25 patients in group 1 and 16 of 23 in group 2 reported satisfaction at 6 months after the operation. Recurrent infection was noted in three patients in each group. Haemoptysis recurred in only one patient in group 2.

Conclusion

The surgical treatment of selected patients with non-localized bronchiectasis was safe and most patients were satisfied with the outcome.
The Structure of Poly(carbonsuboxide) on the Atomic Scale: A Solid‐State NMR Study
Authors: Schmedt auf der Günne Jörn , Beck Johannes , Hoffbauer Wilfried , Krieger‐Beck Petra
Published: May 2005

In this contribution we present a study of the structure of amorphous poly(carbonsuboxide) (C3O2)x by 13C solid‐state NMR spectroscopy supported by infrared spectroscopy and chemical analysis. Poly(carbonsuboxide) was obtained by polymerization of carbonsuboxide C3O2, which in turn was synthesized from malonic acid bis(trimethylsilylester). Two different 13C labeling schemes were applied to probe inter‐ and intramonomeric bonds in the polymer by dipolar solid‐state NMR methods and also to allow quantitative 13C MAS NMR spectra. Four types of carbon environments can be distinguished in the NMR spectra. Double‐quantum and triple‐quantum 2D correlation experiments were used to assign the observed peaks using the through‐space and through‐bond dipolar coupling. In order to obtain distance constraints for the intermonomeric bonds, double‐quantum constant‐time experiments were performed. In these experiments an additional filter step was applied to suppress contributions from not directly bonded 13C,13C spin pairs. The 13C NMR intensities, chemical shifts, connectivities and distances gave constraints for both the polymerization mechanism and the short‐range order of the polymer. The experimental results were complemented by bond lengths predicted by density functional theory methods for several previously suggested models. Based on the presented evidence we can unambiguously exclude models based on γ‐pyronic units and support models based on α‐pyronic units. The possibility of planar ladder‐ and bracelet‐like α‐pyronic structures is discussed.
Red cell mass and plasma volume measurements in polycythemia:
Authors: Sirhan Shireen , Fairbanks Virgil F. , Tefferi Ayalew
Published: May 2005

BACKGROUND

Despite the absence of any systematic evidence for diagnostic utility, red cell mass (RCM) measurement has been endorsed as a major diagnostic criterion for polycythemia vera (PV) based on a set of eligibility criteria for a clinical trial formulated by an International PV Study Group in 1967.

METHODS

A retrospective analysis was performed on a consecutive series of 105 patients who underwent blood volume measurements for evaluation of polycythemia. In a previous study, the authors had systematically compared RCM measurement by 51Cr‐labeled erythrocytes and 125I‐labeled human serum albumin and demonstrated equivalence between the two methods. In the current study, they used the latter method and applied the International Committee for Standardization in Haematology recommendations for result interpretation in order to evaluate test performance and practical utility.

RESULTS

RCM exceeded the 98–99% limits of the reference range in 76%, 20%, 22%, and 57% of patients with PV (n = 25), secondary polycythemia (n = 35), spurious or apparent polycythemia (n = 38), and essential thrombocythemia (n = 7), respectively. Decreased plasma volume was rarely seen in any of the disease categories. In all instances of PV, the diagnosis was readily apparent, based on alternative clinical and laboratory tests, and did not require the additional information from blood volume measurement. Furthermore, alternative methods of PV diagnosis, based on disease‐specific biological markers as well as bone marrow histology, are now available.

CONCLUSIONS

The continued use of RCM and plasma volume measurements for the diagnosis of PV is no longer warranted. Cancer 2005. ©2005 American Cancer Society.
Medial olivocochlear reflex interneurons are located in the posteroventral cochlear nucleus: A kainic acid lesion study in guinea pigs
Authors: De Venecia Ronald K. , Liberman M. Charles , Guinan John J. , Brown M. Christian
Published: May 2005

The medial olivocochlear (MOC) reflex arc is probably a three‐neuron pathway consisting of type I spiral ganglion neurons, reflex interneurons in the cochlear nucleus, and MOC neurons that project to the outer hair cells of the cochlea. We investigated the identity of MOC reflex interneurons in the cochlear nucleus by assaying their regional distribution using focal injections of kainic acid. Our reflex metric was the amount of change in the distortion product otoacoustic emission (at 2f1–f2) just after onset of the primary tones. This metric for MOC reflex strength has been shown to depend on an intact reflex pathway. Lesions involving the posteroventral cochlear nucleus (PVCN), but not the other subdivisions, produced long‐term decreases in MOC reflex strength. The degree of cell loss within the dorsal part of the PVCN was a predictor of whether the lesion affected MOC reflex strength. We suggest that multipolar cells within the PVCN have the distribution and response characteristics appropriate to be the MOC reflex interneurons. J. Comp. Neurol. 487:345–360, 2005. © 2005 Wiley‐Liss, Inc.
Neuroanatomic deficits in congenital central hypoventilation syndrome
Authors: Kumar Rajesh , Macey Paul M. , Woo Mary A. , Alger Jeffry R. , Keens Thomas G. , Harper Ronald M.
Published: May 2005

Congenital Central Hypoventilation Syndrome (CCHS) patients exhibit compromised autonomic regulation, reduced breathing drive during sleep, diminished ventilatory responses to chemoreceptor stimulation, and diminished air hunger perception. The syndrome provides an opportunity to partition neural processes regulating breathing and cardiovascular action. No obvious lesions appear with conventional magnetic resonance imaging; however, T2 relaxometry procedures can detect reduced cell or fiber density or diminished myelination not found with routine evaluation. High‐resolution T1, proton density, and T2‐weighted brain images were collected from 12 patients and 28 age‐ and gender‐matched controls. Voxel‐by‐voxel T2 maps were generated from the proton density and T2‐weighted images and evaluated by voxel‐based‐relaxometry procedures. Normalized and smoothed T2 maps were compared between groups using analysis of covariance at each voxel, with age and ventricle size included as covariates. Patients showed damaged or maldeveloped tissue, principally right‐sided, including white matter from the level of the anterior cingulate cortex caudally to the level of the posterior cingulate and laterally to the posterior superior temporal cortex. Portions of the posterior, mid, and anterior cingulate, as well as the internal capsule, putamen, and globus pallidus and basal forebrain extending to the anterior and medial thalamus were affected. Deficits in the cingulum bundle and mid‐hippocampus and ventral prefrontal cortex appeared, as well as the right cerebellar cortex and deep nuclei. Neuroanatomic deficiencies in limbic structures suggest a structural basis for reduced air hunger perception, thermoregulatory and autonomic deficiencies in the syndrome, while cerebellar deficits may also contribute to breathing and cardiovascular dysregulation. J. Comp. Neurol. 487:361–371, 2005. © 2005 Wiley‐Liss, Inc.