bluuebunny/crossref_metadata_2025 huggingface dataset:
Chemically Functionalized Clay Vinyl Ester Nanocomposites II - Vernonia Oil-based Surfactant
Authors: Balakrishnan S. , Raghavan D.
Published: December 2004

The primary objective of this study is to examine the role of reactive and nonreactive surfactants in exfoliation and dispersion of clay platelets in vinyl ester resin and evaluate the mechanical properties of final nanocomposites. The morphology of the nanocomposites was characterized using X-ray Diffraction (XRD) and Transmission Electron Microscopy (TEM) and the mechanical properties of the nanocomposite were determined by performing tensile measurements. When the clay was ion-exchanged with a combination of reactive and nonreactive surfactants and mixed with vinyl ester resin, a partially exfoliated vinyl ester nanocomposite was formulated. The degree of dispersion of the clay platelets in vinyl ester matrix was found to be sensitive to the chemistry associated with clay platelet modification, reactive comonomer, and processing conditions. At montmorillonite clay content of only 2.5 wt%, the modulus improved by 20% in partially reactive organoclay dispersed nanocomposite, while the modulus improved by 10% in nonreactive organoclay-dispersed nanocomposite compared to that of unfilled cured vinyl ester resin.
Injection Pultrusion Simulation for Polyester/Glass Mat/Rovings/Mat Composites
Authors: Rahatekar S. S. , Roux J. A.
Published: December 2004

Producing quality pultruded parts requires that complete wet out of the reinforcement fibers is achieved in the injection chamber. The magnitude of the injection pressure is extremely important for achieving good wet out of the fibers. This work focused on the impact of pull speed, resin viscosity, and product thickness on resin fiber wet out in the injection chamber for a polyester resin (mat/roving/mat) composite. Recommended injection pressures for complete wet out are predicted for given sets of processing parameters for polyester/glass fiber (mat/rovings/mat) composites. Flow through porous media (Darcy’s law) is employed to model the fiber/resin system of injection pultrusion. The governing equations are solved, by using the finite volume method, to predict the resin pressure, resin velocity field, and resin moving flow front location. The Gutowski (Gutowski, T.G., Morigaki, T. and Cai, Z. (1987). The Consolidation of Laminate Composites, Journal of Composite Materials. 21(7): 172-187) permeability model is used to determine the permeability in the roving layer and the Kozeny-Carman (Carman, P.C. (1939). Flow through Granular Beds, Trans. Int. Chem. Eng., 15: 150-166) model is used to predict the permeability in the mat layers.
Free-vibration of Composite Beam-columns with Stochastic Material and Geometric Properties Subjected to Random Axial Loads
Authors: Ganesan Rajamohan , Kowda Vijay Kumar
Published: December 2004

Beam-columns made of polymer-matrix fiber-reinforced composite materials are increasingly being used in automotive, aerospace, structural, and mechanical engineering industries. The composite materials display significant variability in their material properties. The composite laminates also display significant variability in their geometric and structural properties. Randomness exists in the axial loads and in the support conditions. As a result, the natural frequencies of composite beam-columns become random variables. The present work considers such composite beam-columns with the objective of determining the mean values and variances of natural frequencies. The randomness in the material and geometric properties of the laminated beam-columns are modeled using stationary stochastic fields in space. Each natural frequency is expressed as a perturbation series. The corresponding normal mode is also expressed as a compatible perturbation series. The perturbation method is employed in the context of stochastic analysis. The equations for sample realizations of natural frequencies and normal modes are derived. Using the sample realizations and the first-order second-moment probabilistic analysis the statistics of natural frequencies are determined. A parametric study on beam-columns made of NCT-301 graphite-epoxy composite material is conducted.
Maggie Lena Walker and African American Community Development
Authors: Schiele Jerome H. , Jackson M. Sebrena , Fairfax Colita Nichols
Published: December 2004

One of the unsung heroines of the African American tradition of community development is Maggie Lena Walker. Walker was the first woman in the United States to establish a bank that still exists today. She also started a merchandise department store, operated a newspaper, and was a prominent leader in a major African American mutual aid organization—the Independent Order of St. Luke. This article discusses Walker’s community development contributions and examines their relevance for contemporary community practice with African Americans.
Progress for Women Faculty in Social Work Academia
Authors: Di Palma Sunday
Published: December 2004

The literature on women’s progress in various disciplines in U.S. higher education, including social work academia, has generally concluded that women continue to be discriminated against. This article presents a study of data from 1974 to 2000 to evaluate this claim. I conclude that although women continue to be under-represented on the faculties of U.S. colleges and universities across disciplines, women social work faculty have made great progress. Possible reasons for these findings are considered.
Lessons Learned from the Last Twenty Years of Sexual Violence Research
Authors: Marx Brian P.
Published: December 2004

The present article attempts to answer important questions about the most important thing learned from the past 20 years of research on sexual violence, the most important thing to be learned about sexual violence over the next 10 years, and the most promising methodological innovation in the study of sexual violence from the last 20 years. It is hoped that discussion of such important questions might further stimulate researchers and mental health professionals to continue making progress in our understanding of, as well as the struggle against, sexual violence.
Domestic Violence Between Same-Gender Partners
Authors: McClennen Joan C.
Published: December 2004

Empirical literature about same-gender domestic violence was relatively nonexistent until the past 20 years, and conducting research with this population about a sensitive topic remains a daunting endeavor. Existing studies reveal similarities between opposite-and same-gender domestic violence in prevalence, types of abuse, and various dynamics, as well as dispel myths and establish a theoretical basis on which to conduct future research. Differences are evident in areas such as help-seeking behaviors and correlates, thus demanding unique assessment and intervention strategies. This article presents further explanation of the latest research, recommendations for future studies, and effective as well as problematic methodological practices about same-gender domestic violence.
What We Know and What We Still Need to Learn
Authors: Humphreys Janice , Sharps Phyllis W. , Campbell Jacquelyn C.
Published: December 2004

Research has changed the conceptualization of the causes and consequences of violence. Yet some questions remain unanswered. Infants and young children have largely been overlooked, and intraethnic and cultural group variations have not been addressed. There is still a need to address macro-level systematic discrimination in the health care system along with the intrapersonal physiological changes that result from exposure to violence. Fortunately, studies are beginning to show how longitudinal and intervention research can be safely conducted.
Culture and Domestic Violence
Authors: Bent-Goodley Tricia B.
Published: December 2004

Cultural competence continues to receive limited attention in domestic violence service provision from research to the evaluation of programs. Yet with changing demo-graphics reflecting larger numbers of people of color and increasing needs for more effective responses, it is critical that we change the way we think about domestic violence. Using a feminist framework, this article examines how knowledge has been developed in domestic violence and its consequence related to service provision and perceptions. The article ends with recommendations as to how to better include culturally competent responses in domestic violence.
Student Online Self-Assessment: Structuring Individual-Level Learning in a new Venture Creation Course
Authors: Human Sherrie E. , Clark Thomas , Baucus Melissa S.
Published: December 2004

The use of self-assessment instruments to determine students’entrepreneurial characteristics represents a well-accepted practice in entrepreneurship courses, and many professors are only now beginning to embrace Web-based instruments. We describe how we use a comprehensive array of online self-assessments in an undergraduate New Venture Creation course required of Xavier University entrepreneurship majors. We illustrate how we designed in-class and out-of-class assignments around these self-assessments using Bandura’s social learning theory. Our approach can be adapted to other types of management courses by modifying the set of self-assessments and the design of assignments to the particular course objectives.
What the Shadow Knows: Exploring the Hidden Dimensions of the Consumer Metaphor in Management Education
Authors: Gross Michael A. , Hogler Raymond
Published: December 2004

This article aims to uncover hidden dimensions of the metaphor of consumerism in management education. By exploring the metaphor, the authors elucidate the implicit claims in the assertion that teachers produce business education and students consume that product. The image of commodification structures a discourse that involves conceptions of power, knowledge, and socially useful activity. The discourse emanates from social and educational institutions that shape relations between students and teachers. To understand how the metaphor creates subjective perceptions, the authors propose a linguistic-based framework as an analytical device. They conclude with specific reference to teaching activities and ways in which the so-called shadow of consumerism can be empirically examined.
Using a Dual Role Assignment to Improve Group Dynamics and Performance: The Effects of Facilitating Social Capital in Teams
Authors: Aquino Karl , Serva Mark A.
Published: December 2004

This article describes a project that simulates the interplay between management and development project teams in a business environment. Each student team was assigned a management role supervising one project and a development role implementing another project. Results indicate that teams that communicate regularly and interact socially outside of class form more social capital. Development teams with dense social capital also voluntarily completed tasks beyond their responsibilities, and management teams perceived higher performance from their development teams. The authors discuss how this simulation can be used to increase learning, along with how the simulation increases the richness of the learning environment.
Creating a Total Quality Environment (TQE) for Learning
Authors: Freed Jann E.
Published: December 2004

This article describes a model for creating a total quality environment (TQE) for learning in which everyone is considered a learner. The model consists of 11 interrelated characteristics derived from the literature in the areas of continuous improvement, leadership, learning, learning organizations, and spirituality. The characteristics in the model are applicable at every institution, every level, and every course.
Damage-based Formability Analysis for TWBs
Authors: Chan L. C. , Cheng C. H. , Jie M. , Chow C. L.
Published: December 2004

This paper describes a damage-based formability analysis for tailor-welded blanks (TWBs) using an anisotropic damage model and damage criterion for localized necking. The damage model and criterion are coupled into finite element code to simulate the stamping process of JIS G3141 steel TWBs. Forming limit strains are computed based on the damage criterion for different values of strain ratio. The computed limit strains are found to be satisfactory as compared with the measured values, thus validating the anisotropic damage model and the failure criterion of TWBs at localized necking.
Attitudes Toward Rape
Authors: Lee Joohee , Pomeroy Elizabeth C. , Yoo Seo-Koo , Rheinboldt Kurt T.
Published: December 2004

The purpose of this study is to investigate differences in attitudes toward rape between Asian and Caucasian college students. The Attitudes Toward Rape scale was used to measure beliefs about rape in a convenience sample of 169 college students. Three items regarding stranger rape myths were added. Findings suggest that Asian students are more likely than Caucasian students to believe women should be held responsible for preventing rape and to view sex as the primary motivation for rape. Asians also have stronger beliefs than Caucasians do that victims cause the rape and that most rapists are strangers. This research suggests that outreach programs can play an important role in providing information, education, and prevention regarding rape and that males and Asian students should be target populations for such programs.
Note: The Effect of Silo Milk Composition Parameters on Heat Stability of Whole Milk Powder
Authors: Negri L. M. , Chavez M. S. , Taverna M. A. , Cuatrin A. L. , Rubiolo A. C.
Published: December 2004

The aim of this work was to study silo raw milk (SRM) compositional parameters that affect the heat stability of whole milk powder (WMP). Seasonal changes of heat stability from SRM and WMP were also characterised. Silo raw milk samples and the corresponding WMP samples were collected twice a month from a local factory from April 2000 to April 2001. Silo raw milk heat coagulation time (HCT), urea and lactose concentrations were found to contribute to milk powder HCT statistical model (R2 = 0.72). High HCT values during summer and low ones during spring were detected for both SRM and WMP samples. Heat coagulation time values of SRM were always higher than those measured in their powders, due to the effects of processing conditions on heat stability
Homogenization of a Sandwich Structure and Validity of the Corresponding Two-dimensional Equivalent Model
Authors: Saidi A. , Coorevits P. , Guessasma M.
Published: December 2004

The aim of this paper is to present a method allowing us to obtain the three-dimensional (3D) modeling of sandwich structures by a two-dimensional (2D) equivalent plate-type model. This modeling is carried out by using the homogenization method of periodic media based on the technique of asymptotic expansions. We propose a new method of identifying the 2D equivalent model parameters that are required by most well-known softwares. The validity of the 2D models obtained is studied by comparing the 3D and 2D calculation results through the definition of two error indicators in terms of displacement and stress.
Oprah’s Book Club and the politics of cross-racial empathy
Authors: Davis Kimberly Chabot
Published: December 2004

Cultural critics often view the sympathy that white audiences may feel when encountering African-American culture as a process of co-optation that does little to upset racial hierarchies. To complicate the predominant critical view that cross-racial sympathy is inevitably imperialistic, this article offers a reception study of Oprah Winfrey’s televised Book Club programs, focusing on white female fans discussing black women’s fiction. While some white readers displayed a problematic ‘color-blindness’ with imperialist overtones, others experienced transformative identifications with black subjects and a reflective alienation from white privilege. Although cross-racial sympathy can often devolve into a colonizing appropriation, my reception analysis underscores the important role that empathetic crossings within cultural space can play in the development of anti-racist coalitions. In examining the relationship of fiction reading to political change, I argue that the public and private spheres are intertwined rather than diametrically opposed.
Do Occupational Groups Vary in Expressed Organizational Culture Preferences?
Authors: Kwantes Catherine T. , Boglarsky Cheryl A.
Published: December 2004

The objective of our study was to examine whether there are differences in how employees in six occupations (Accounting, Management Information Systems, Marketing, Production, and Secretarial/Clerical) describe the organizational culture in which they felt they would be most effective. The differences found within the context of one national culture were differences in degree rather than in kind. Members of each occupational group indicated that an organizational culture that emphasizes constructive interpersonal relationships, participative management, and values individual work initiative and task accomplishment is preferred. Management Information Systems emerged as having significantly more extreme preferences in their description of an ideal organizational culture. Additionally, it was found that the professional occupations had distinctly different degrees of preferences for specific types of organizational culture than the non-professional occupations. The dominant type of work (person-oriented vs. task-oriented) also had an effect on organizational culture preferences.
School Principals as Standards-Based Educational Leaders
Authors: Marsh David D. , LeFever Karen
Published: December 2004

Is it possible for principals/heads to be effective educational leaders? In this study, we compared the work of principals/heads in two policy contexts. In Policy Context 1, standards for student performance were common and well-established, and authority was devolved to the school level for reshaping the school to meet those standards. In contrast, Policy Context 2 involved attention to more locally defined standards, and authority was more rule-driven rather than directed by local self-management. Policy Context 1 provided several advantages for educational leaders. Principals/heads were able to use the formal leadership structure of the school and to be more focused on actually achieving student results as measured against standards. In contrast, principals in Policy Context 2 often had to spend considerable personal energy helping the school define its purpose/mission, and could not hold the collaborative focus tightly on a specific set of student standards or results. Implications for job structuring, principal development, and connections between policy and practice are discussed.
Challenging the Orthodoxies
Authors: Flecknoe Mervyn
Published: December 2004

This article examines the relationships that link student experience in schools, student outcomes, the nature of society and school leadership process. Each of these areas of study has its own literature and this article does no more than indicate where some of that may be read. The linking of these phenomena indicates a tight relationship, which militates against change and explains a very conservative, internally consistent, cycle. The cycle may reinforce characteristics of society that are unwelcome: for instance, the low turnout at elections and a perceived lack of other citizenship traits. A premise of this article is that we should seek to create a society in which citizens feel responsible for the strategic determination of policy, whether about relations with other states or about the culture within the UK. Change will require actors at some stage in the cycle to break away from the tight relationship with the other phenomena. Those who are responsible for the professional development of educational leaders are uniquely situated to put a spoke into the cycle.
Rhetorical Resources for Management
Authors: Svedberg Lars
Published: December 2004

Managing organizations in modern societies takes place through persuasion and the seductive use of language rather than, as in past societies, through physical violence and repression. In this respect new management discourses imply a linguistic process where actors within education gradually become defined within other frames of reference. This article sets out to unpack and reconstruct perceptions of educational leadership in a report from the Ministry of Education and Science entitled Learning Leaders: Leadership for Today’s and Tomorrow’s School. It is inspired by Potter’s understanding of discourse. If a democratic, learning and communicative leadership is the solution — what are the problems and causes? What kind of problematic yesterday is the point of departure, and what is the promised future like? I will argue that the leader emerges as a function of a changed way to exercise power.
MALT1 and the API2-MALT1 fusion act between CD40 and IKK and confer NF-κB-dependent proliferative advantage and resistance against FAS-induced cell death in B cells
Authors: Ho Liza , Davis R. Eric , Conne Béatrice , Chappuis Richard , Berczy Margaret , Mhawech Paulette , Staudt Louis M. , Schwaller Juerg
Published: December 2004

The most frequently recurring translocations in mucosa-associated lymphoid tissue (MALT) B-cell non-Hodgkin lymphoma, t(11;18)(q21;q21) and t(14;18)(q32; q21), lead to formation of an API2-MALT1 fusion or IgH-mediated MALT1 overexpression. Various approaches have implicated these proteins in nuclear factor κB (NF-κB) signaling, but this has not been shown experimentally in human B cells. Immunohistochemistry showed that MALT1 is predominantly expressed in normal and malignant germinal center B cells, corresponding to the differentiation stage of MALT lymphoma. We expressed MALT1 and apoptosis inhibitor-2 API2/MALT1 in human B-cell lymphoma BJAB cells and found both transgenes in membrane lipid rafts along with endogenous MALT1 and 2 binding partners involved in NF-κB signaling, B-cell lymphoma 10 (BCL10) and CARMA1 (caspase recruitment domain [CARD]-containing membrane-associated guanylate kinase [MAGUK] 1). API2-MALT1 and exogenous MALT1 increased constitutive NF-κB activity and enhanced IκB kinase (IKK) activation induced by CD40 stimulation. Both transgenes protected BJAB cells from FAS (CD95)-induced death, consistent with increases in NF-κB cytoprotective target gene expression, and increased their proliferation rate. Expression of a dominant-negative IκBα mutant showed that these survival and proliferative advantages are dependent on elevated constitutive NF-κB activity. Our findings support a model in which NF-κB signaling, once activated in a CD40-dependent immune response, is maintained and enhanced through deregulation of MALT1 or formation of an API2-MALT1 fusion.
Association of transplant center and physician factors on mortality after hematopoietic stem cell transplantation in the United States
Authors: Loberiza Fausto R. , Zhang Mei-Jie , Lee Stephanie J. , Klein John P. , LeMaistre Charles F. , Serna Derek S. , Eapen Mary , Bredeson Christopher N. , Horowitz Mary M. , Rizzo J. Douglas
Published: December 2004

The effect of the organization and delivery of health care at medical centers, referred to as “center effects,” with clinical outcomes after hematopoietic stem cell transplantation (HSCT) is not clear. We examined the association between center and treatment provider factors and mortality after HSCT. We surveyed 163 (87% response rate) United States transplantation centers that performed HLA-identical sibling HSCT for leukemia or autologous HSCT for lymphoma between 1998 and 2000 among patients at least 18 years old. One hundred thirteen (69%) centers performed HLA-identical sibling transplantations, whereas 162 (99%) performed autologous transplantations. Factors associated with decreased 100-day mortality in the allogeneic setting include a higher patient-per-physician ratio (P = .003) and centers where physicians answer calls after office hours (P = .03). Medical school affiliation was not associated with increased 100-day mortality except in centers where students/residents are present without fellows (P = .02). Center effects were weaker in autologous HSCT at 1 year. Differences in 100-day mortality in patients receiving transplants in centers with favorable versus unfavorable factors were greater in allogeneic than autologous HSCT. Greater physician involvement in patient care is important in producing favorable outcomes after HSCT. To more clearly establish the role of the factors we identified, further studies are recommended.
Condensing temperature control to enhance the efficiency of air-cooled chillers
Authors: Yu FW , Chan KT
Published: December 2004

This paper describes an operating strategy of condensing temperature control (CTC), which means regulating the set point of condensing temperature based on the outdoor temperature, to enhance the efficiency of air-cooled chillers used in air-conditioned buildings. A mathematical model of an air-cooled chiller is developed for simulation and is validated by using the operating data of an existing chiller and of an experimental chiller. Compared to head pressure control (HPC) with a fixed set point of condensing temperature, CTC brings a moderate rise in the condensing temperature above the outdoor temperature, and hence enables the compressors to operate at a lower condensing pressure through staging more condenser fans. While more condenser fan power is consumed, compressor power can drop considerablely, reducing the annual chiller power consumption by 18.4%. It is suggested that the condensing temperature can be coupled with the outdoor temperature and the part load ratio of chillers to gauge the achievable part load efficiency.
A convergent optimization method using pattern search algorithms with adaptive precision simulation
Authors: Wetter M , Polak E
Published: December 2004

Thermal building simulation programs, such as EnergyPlus, compute numerical approximations to solutions of systems of differential algebraic equations. We show that the exact solutions of these systems are usually smooth in the building design parameters, but that the numerical approximations are usually discontinuous due to adaptive solvers and finite precision computations. If such approximate solutions are used in conjunction with optimization algorithms that depend on smoothness of the cost function, one needs to compute high precision solutions, which can be prohibitively expensive if used for all iterations. For such situations, we have developed an adaptive simulation–precision control algorithm that can be used in conjunction with a family of derivative free optimization algorithms. We present the main ingredients of the composite algorithms, we prove that the resulting composite algorithms construct sequences with stationary accumulation points, and we show by numerical experiments that using coarse approximations in the early iterations can significantly reduce computation time.
A ducted wind turbine model for building simulation
Authors: Grant A , Kelly N
Published: December 2004

Power production is shifting away from centralized generation plants to production of heat and power at the point of demand. A technology that may play a part in this shift is the ducted wind turbine (DWT). The emergence of small building integrated micro turbines opens up the possibility of utilizing the differential pressures occurring around buildings for local power production. This paper describes work to develop and test a simple mathematical model of a ducted wind turbine and its integration within a building simulation tool. A case study in which the simulation model will be used to analyse of the likely power output from a building incorporating ducted wind turbines within the façade is also presented.
Lighting for work: a review of visual and biological effects
Authors: van Bommel WJM , van den Beld GJ
Published: December 2004

With the detection in 2002 of a novel photoreceptor cell in the eye, the biological effects that light has can be better understood. From the research on the biological effects of lighting, it is evident that the rules governing the design of good and healthy lighting installations are, to a certain degree, different from the conventionally held rules. We demonstrate that it can be beneficial to be able to adapt both the level and the colour of the lighting. Not only the light on the visual task, but also that entering the eye determines the overall quality of lighting. In a working environment, not only are the advantages in terms of health and wellbeing important for the workers themselves, they also lead to better work performance, fewer errors, better safety, and lower absenteeism.
An examination of the fundamentals of road lighting for pedestrians and drivers
Authors: Raynham P
Published: December 2004

The current principles of road lighting design are well established and have been adopted in a number of lighting design standards. This paper questions the basis of these principles and looks at some of the anomalies and problems of current road lighting design practice. The development of road lighting for pedestrians is examined, and the benefits of having a relevant visual task are explored. The paper concludes by suggesting that the fundamentals of road lighting need further examination.
Tumor-Associated Macrophages: The Double-Edged Sword in Cancer Progression
Authors: Chen Jeremy J.W. , Lin Yi-Chen , Yao Pei-Li , Yuan Ang , Chen Hsang-Yu , Shun Chia-Tung , Tsai Meng-Feng , Chen Chun-Houh , Yang Pan-Chyr
Published: December 2004

Purpose

Inflammation plays a critical role in cancer progression. In this study we investigate the pro-tumorigenic activities and gene expression profiles of lung cancer cells after interaction with macrophages.

Materials and Methods

We measured intratumoral microvessel counts and macrophage density in 41 lung cancer tumor specimens and correlated these with the patients' clinical outcome. The interaction between macrophages and cancer cell lines was assessed using a transwell coculture system. The invasive potential was evaluated by in vitro invasion assay. The matrix-degrading activity was assayed by gelatin zymography. The microarray was applied to a large-scale analysis of the genes involved in the interaction, as well as to monitor the gene expression profiles of lung cancer cells responding to anti-inflammatory drugs in cocultures.

Results

The macrophage density positively correlated with microvessel counts and negatively correlated with patient relapse-free survival (P < .05). After coculture with macrophages, lung cancer cell lines exhibited higher invasive potentials and matrix-degrading activities. We identified 50 genes by microarray that were upregulated more than two-fold in cancer cells after coculture. Northern blot analyses confirmed some gene expression such as interleukin-6, interleukin-8, and matrix metalloproteinase 9. The two-dimensional hierarchical clustering also demonstrated that the gene expression profiles of lung cancer cells responding to various anti-inflammatory drugs in cocultures are distinct.

Conclusion

The interaction of lung cancer cells and macrophages can promote the invasiveness and matrix-degrading activity of cancer cells. Our results also suggest that a great diversity of gene expression occurs in this interaction, which may assist us in understanding the process of cancer metastasis.
Pancreatic Islet Adaptation to Fasting Is Dependent on Peroxisome Proliferator-Activated Receptor α Transcriptional Up-Regulation of Fatty Acid Oxidation
Authors: Gremlich Sandrine , Nolan Christopher , Roduit Raphaël , Burcelin Rémy , Peyot Marie-Line , Delghingaro-Augusto Viviane , Desvergne Béatrice , Michalik Liliane , Prentki Marc , Wahli Walter
Published: December 2004

The cellular response to fasting and starvation in tissues such as heart, skeletal muscle, and liver requires peroxisome proliferator-activated receptor-α (PPARα)-dependent up-regulation of energy metabolism toward fatty acid oxidation (FAO). PPARα null (PPARαKO) mice develop hyperinsulinemic hypoglycemia in the fasting state, and we previously showed that PPARα expression is increased in islets at low glucose. On this basis, we hypothesized that enhanced PPARα expression and FAO, via depletion of lipid-signaling molecule(s) for insulin exocytosis, are also involved in the normal adaptive response of the islet to fasting. Fasted PPARαKO mice compared with wild-type mice had supranormal ip glucose tolerance due to increased plasma insulin levels. Isolated islets from the PPARα null mice had a 44% reduction in FAO, normal glucose use and oxidation, and enhanced glucose-induced insulin secretion. In normal rats, fasting for 24 h increased islet PPARα, carnitine palmitoyltransferase 1, and uncoupling protein-2 mRNA expression by 60%, 62%, and 82%, respectively. The data are consistent with the view that PPARα, via transcriptionally up-regulating islet FAO, can reduce insulin secretion, and that this mechanism is involved in the normal physiological response of the pancreatic islet to fasting such that hypoglycemia is avoided.
Enteric-coated cholylsarcosine microgranules for the treatment of short bowel syndrome
Authors: Fürst Th , Bott C , Stein J , Dressman J B
Published: December 2004

Cholylsarcosine (CS) is a semisynthetic bile salt that may be useful in bile salt replacement therapy of short bowel syndrome (SBS). In SBS the bile salt pool becomes depleted, disturbing the uptake of dietary lipids and resulting in weight loss. Previous studies showed that CS in a simple capsule formulation of 1.5–12 g day−1 can increase the uptake of lipids but often results in gastric irritation. In this work a microgranule dosage form was developed to protect the gastric mucosa while facilitating rapid generation of CS levels in the duodenum. CS microgranules were produced by wet granulation and coated with Eudragit L30D-55 in a fluidized-bed coater. The in-vitro dissolution rate of CS from the microgranules was investigated with USP apparatus under fasted- and fed-state conditions. CS release was delayed under simulated gastric conditions (pH 1.2 and 4.5) but was very fast at higher pH values (5.5, 5.8 and 6.5) more typical of the duodenum. In a pilot clinical trial, four patients received 4 g CS with meals (1.5 g with lunch, 2.5 g with dinner) for 1 week. The parameters investigated were fat absorption coefficient (FAC%), serum β-carotene level and faecal weight. Although study numbers were too small to achieve statistical significance, the serum β-carotene level and FAC% increased in the three patients who completed the trial. As expected, the fecal weight did not change. The results indicate that the CS microgranules are promising for the treatment of the intraluminal bile salt deficiency in patients with SBS.
Pharmaceutical applications of mucoadhesion for the non-oral routes
Authors: Edsman Katarina , Hägerström Helene
Published: December 2004

The adhesion of pharmaceutical formulations to the mucosal tissue offers the possibility of creating an intimate and prolonged contact at the site of administration. This prolonged residence time can result in enhanced absorption and, in combination with a controlled release of the drug, also improved patient compliance by reducing the frequency of administration. During the almost 30 years over which mucoadhesion has been studied, a considerable amount of knowledge has been gained, and much has been learned about the different mechanisms occurring at the formulation-mucus interface and the properties that affect these mechanisms. The in-vivo performance of a dosage form not only depends on the mechanisms occurring at the interface, but also on the properties of the total mucoadhesive complex: the dosage form, the mucosa and the interface between them. A wide variety of methods are used for studying mucoadhesion; some rather similar to the in-vivo situation and some mimicking the interface alone. In this review, the mucus surface, the methods used for the study of mucoadhesion, the different mechanisms involved in mucoadhesion and theories underpinning them have been described. The complexity of mucoadhesion when trying to systemize the subject will also be discussed. The last part of the review describes the buccal, nasal, ocular, vaginal and rectal routes and provides examples of what can be achieved in-vivo when using mucoadhesive formulations.
Cardiovascular development in embryos of the American alligator Alligator mississippiensis: effects of chronic and acute hypoxia
Authors: Crossley Dane A. , Altimiras Jordi
Published: December 2004

Chronic hypoxic incubation is a common tool used to address the plasticity of morphological and physiological characteristics during vertebrate development. In this study chronic hypoxic incubation of embryonic American alligators resulted in both morphological (mass) and physiological changes. During normoxic incubation embryonic mass, liver mass and heart mass increased throughout the period of study, while yolk mass fell. Chronic hypoxia(10%O2) resulted in a reduced embryonic mass at 80% and 90% of incubation. This reduction in embryonic mass was accompanied by a relative enlargement of the heart at 80% and 90% of incubation, while relative embryonic liver mass was similar to the normoxic group. Normoxic incubated alligators maintained a constant heart rate during the period of study, while mean arterial pressure rose continuously. Both levels of hypoxic incubation(15% and 10%O2) resulted in a lower mean arterial pressure at 90%of incubation, while heart rate was lower in the 10%O2 group only. Acute (5 min) exposure to 10%O2 in the normoxic group resulted in a biphasic response, with a normotensive bradycardia occurring during the period of exposure and a hypertensive tachycardic response occurring during recovery. The embryos incubated under hypoxia also showed a blunted response to acute hypoxic stress. In conclusion, the main responses elicited by chronic hypoxic incubation, namely, cardiac enlargement, blunted hypoxic response and systemic vasodilation, may provide chronically hypoxic embryos with a new physiological repertoire for responding to hypoxia.
A comparison of methods for modelling the dynamics of a cricket bat
Authors: Gutaj F
Published: December 2004

The dynamic characteristics of a cricket bat may be quantified using different modelling methods ranging from rigid-body models, flexible beam models, finite element (FE) models and modal models. This paper compares three models of a cricket bat. The first is an experimentally validated FE model. The validation of the FE model is described via correlation and mapping of results from experimental modal testing to FE calculated results via optimization procedures. Using the methodology described here, the actual bat dynamic characteristics can be identified to a reasonable level. The second and third models included a tapered and uniform beam model of the cricket bat. Although not predicting the frequencies of vibration of the higher modes as accurately as the FE model, the uniform beam model was useful as it provided a means for correlation of the taper model for the case when the condition of zero taper is approached. Results from parameter sensitivity analyses with each beam model were used to gain an insight into the influence of geometric and material properties on bat vibration characteristics. The combined use of beam model results and FE modelling was found to be an efficient means for quantifying the effect of material and geometric variations on bat dynamic characteristics. With the experimental, numerical and theoretical techniques presented in this paper, the aim of providing an informed choice for alternative bat designs was achieved.
Study of magnetomechanical non-linear deformation of ferromagnetic materials: Theory and experiment
Authors: Fang D N , Feng X , Hwang K C
Published: December 2004

A robust constitutive model is desirable in order to guide the processing and development of ferromagnetism and for use in the design of ferromagnetic devices. In this paper, a non-linear constitutive model of soft ferromagnets is developed for general magnetomechanical loading histories. The experimental set-up and measured techniques, which were employed to measure the non-linear deformation of both the magnetostrictive materials and the soft ferromagnetic materials subjected to coupled magnetomechanical loading, are introduced. The general structure for the constitutive behaviour of ferromagnets including soft-ferromagnetic and hard-ferromagnetic materials is similar to the classical models of metal plasticity; i.e. a convex yield surface can be identified in a stress-magnetic field space, within which the deformation and magnetization are reversible, and increments of both remanent magnetization and remanent strains are normal to the yield surface. The state of materials is described in terms of the remanent strain and the remanent magnetization that are introduced as internal variables besides stress, strain, magnetic field and magnetization. The one-dimensional model is examined by numerical stimulations and the response of the ferromagnetic materials is discussed in comparison with the measured results. The macroscopic features of ferromagnets, such as hysteresis loop and magnetostrictive hysteresis, are predicted.
Primary hyperparathyroidism in pregnancy
Authors: Jesudason W.V. , Murphy J. , England R.J.A.
Published: December 2004

Primary hyperparathyroidism during pregnancy carries significant risks to both mother and fetus. Parathyroidectomy remains the only definitive treatment for the condition. The timing of surgery remains controversial, with ongoing debate regarding the safety of surgery during the third trimester. A case of symptomatic primary hyperparathyroidism treated by parathyroidectomy in the third trimester is described. The clinical features, investigations and treatment options are discussed.
Smooth muscle tumour of the pharynx: a rare tumour presenting with globus pharyngeus symptoms
Authors: Husamaldin Z. , Aung W. , McFerran D.J.
Published: December 2004

A rare case of a smooth muscle tumour in the pharynx is reported, together with histopathological findings. The patient’s psychiatric background and recurrent complaint of a sensation of a lump in the throat all pointed to a psychogenic aetiology, and diagnosis was delayed. The importance of mirror or endoscopic examination of the pharynx is stressed in patients with globus pharyngeus symptoms.
Balancing Pain and Analgesic Treatment in the Home-Dwelling Elderly
Authors: Hartikainen Sirpa A , Mäntyselkä Pekka T , Louhivuori-Laako Kirsti A , Sulkava Raimo O
Published: December 2004

BACKGROUND:

In elderly persons, pain is a common problem, and analgesic medicines are among the most frequently used drugs.

OBJECTIVE:

To describe the use of analgesic medication and its relation to daily pain and morbidity in home-dwelling elderly people aged at least 75 years.

METHODS:

A random sample of 700 subjects aged at least 75 years was drawn from the total population of Kuopio, Finland. A geriatrician and nurse carried out structured clinical examinations and interviews with 601 persons, 523 of whom were living at home.

RESULTS:

Seventy percent (n = 364) of the elderly people were taking at least one analgesic, including most of those who suffered from daily interfering pain (85%) and nearly all of those experiencing daily pain at rest (93%). Nonsteroidal antiinflammatory drugs (NSAIDs; n = 226, 51%) and acetaminophen (n = 118, 23%) were the most commonly used analgesics. The use of opioids became more common with age, accounting for 16% of the drugs in the oldest patients (≥85 y) and 6% among those aged 75–79 years. Analgesics were mainly taken when needed. Only 13% of NSAID users, 18% of acetaminophen users, and 21% of opioid users took these preparations regularly.

CONCLUSIONS:

Although analgesics are commonly used by elderly patients, it appeared that many patients were still experiencing daily interfering pain and pain at rest.
Verapamil Toxicity Resulting from a Probable Interaction with Telithromycin
Authors: Reed Matthew , Wall Geoffrey C , Shah Niyati P , Heun James M , Hicklin Gregory A
Published: December 2004

OBJECTIVE:

To report a case of hypotension and bradyarrhythmia caused by verapamil toxicity in a patient prescribed telithromycin.

CASE SUMMARY:

A 76-year-old white woman receiving verapamil 180 mg/day for hypertension experienced a sudden onset of shortness of breath and weakness and was found to be profoundly hypotensive and bradycardic, with a systolic blood pressure of 50–60 mm Hg and a heart rate of 30 beats/min. She had been taking telithromycin 800 mg/day for 2 days previously for acute sinusitis. The patient was treated with crystalloids, vasopressors, and transvenous pacing. Approximately 72 hours after admission, her blood pressure and heart rate rapidly returned to normal, and she was discharged several days later.

DISCUSSION:

Telithromycin is a known substrate of the CYP3A4 system, and several pharmacokinetic interactions can occur by displacement of other drugs from this system. Verapamil is metabolized through several cytochrome P450 isoenzyme systems. Although there are no previous reports of an interaction between these drugs, other possible causes for the patient's symptoms were excluded and the diagnosis of a probable interaction between verapamil and telithromycin leading to verapamil toxicity was made.

CONCLUSIONS:

Telithromycin is a ketolide antibiotic approved for treatment of respiratory tract infections and acute sinusitis. The potential for clinically significant drug interactions should be considered before using this agent, especially in patients taking other drugs that are metabolized through the CYP3A system. Caution should be exercised when considering the use of this antibiotic in patients receiving verapamil.
Anandamide-Evoked Activation of Vanilloid Receptor 1 Contributes to the Development of Bladder Hyperreflexia and Nociceptive Transmission to Spinal Dorsal Horn Neurons in Cystitis
Authors: Dinis Paulo , Charrua Ana , Avelino Antonio , Yaqoob Mohammed , Bevan Stuart , Nagy Istvan , Cruz Francisco
Published: December 2004

The role of anandamide in the development of inflammatory hyperalgesia and visceral hyperreflexia was studied in the rat urinary bladder. Animals were given intraperitoneal cyclophosphamide injection, which evokes painful hemorrhagic cystitis accompanied by increased bladder reflex activity. The vanilloid receptor 1 [transient receptor potential vanilloid 1 (TRPV1)] antagonist capsazepine, applied onto the serosal surface of bladders, significantly reduced the hyperreflexia. Mass spectrometric analysis revealed that cyclophosphamide injection significantly and persistently increased the anandamide content of bladder tissues. The increase in the anandamide content paralleled the development of reflex hyperactivity. Anandamide (1-100 μm), applied onto the serosal surface of naive bladders, increased the reflex activity in a concentration-dependent manner. Repeated anandamide applications did not produce desensitization of the response. The anandamide-evoked effect was blocked by capsazepine or by instillation of resiniferatoxin, the ultrapotent TRPV1 agonist, into the bladders 24 hr before the anandamide challenge. The cannabinoid 1 receptor antagonist SR141716A [N-piperidino-5-(4-chlorophenyl)-1-(2,4-dichlorophenyl)-4-methylpyrazole-3-carboxamide] significantly increased the potency of anandamide in enhancing bladder reflex activity in naive but not in cyclophosphamide-injected animals. Application of the fatty acid amide hydrolyze inhibitor palmitoylisopropylamine onto the serosal surface of bladders also increased the reflex activity both in naive and cyclophosphamide-injected rats. This latter effect in naive animals was blocked by capsazepine and by resiniferatoxin pretreatment. Finally, intravesical instillation of anandamide (50 μm) increased c-fosexpression in the spinal cord, which was reduced by capsazepine or by resiniferatoxin pretreatment.

These results suggest that anandamide, through activating TRPV1, contributes to the development of hyperreflexia and hyperalgesia during cystitis.