bluuebunny/crossref_metadata_2025 huggingface dataset:
Regulation of Cellulase Synthesis in Batch and Continuous Cultures of
Clostridium thermocellum
Authors: Yi-Heng Zhang Percival , Lynd Lee R.
Published: December 2004

Regulation
of cell-specific cellulase synthesis (expressed in milligrams of
cellulase per gram [dry weight] of cells) by
Clostridium
thermocellum
was investigated using an enzyme-linked immunosorbent
assay protocol based on antibody raised against a peptide sequence from
the scaffoldin protein of the cellulosome (Zhang and Lynd, Anal. Chem.
75:
219-227, 2003). The cellulase synthesis in
Avicel-grown batch cultures was ninefold greater than that in
cellobiose-grown batch cultures. In substrate-limited continuous
cultures, however, the cellulase synthesis with Avicel-grown cultures
was 1.3- to 2.4-fold greater than that in cellobiose-grown cultures,
depending on the dilution rate. The differences between the cellulase
yields observed during carbon-limited growth on cellulose and the
cellulase yields observed during carbon-limited growth on cellobiose at
the same dilution rate suggest that hydrolysis products other than
cellobiose affect cellulase synthesis during growth on cellulose and/or
that the presence of insoluble cellulose triggers an increase in
cellulase synthesis. Continuous cellobiose-grown cultures maintained
either at high dilution rates or with a high feed substrate
concentration exhibited decreased cellulase synthesis; there was a
large (sevenfold) decrease between 0 and 0.2 g of cellobiose
per liter, and there was a much more gradual further decrease for
cellobiose concentrations >0.2 g/liter. Several factors suggest
that cellulase synthesis in
C. thermocellum
is regulated by
catabolite repression. These factors include: (i) substantially higher
cellulase yields observed during batch growth on Avicel than during
batch growth on cellobiose, (ii) a strong negative correlation between
the cellobiose concentration and the cellulase yield in continuous
cultures with varied dilution rates at a constant feed substrate
concentration and also with varied feed substrate concentrations at a
constant dilution rate, and (iii) the presence of sequences
corresponding to key elements of catabolite repression systems in the
C. thermocellum
genome.
MOLECULAR APPROACHES TO MARINE MICROBIAL ECOLOGY AND THE MARINE NITROGEN CYCLE
Authors: Ward Bess B.
Published: December 2004

▪ Abstract  Microbes are recognized as important components of the Earth system, playing key roles in controlling the composition of the atmosphere and surface waters, forming the basis of the marine food web, and the cycling of chemicals in the ocean. A revolution in microbial ecology has occurred in the past 15–20 years with the advent of rapid methods for discovering and sequencing the genes of uncultivated microbes from natural environments. Initially based on sequences from the 16S rRNA gene, this revolution made it possible to identify microorganisms without first cultivating them, to discover and characterize the immense previously unsuspected diversity of the microbial world, and to reconstruct the evolutionary relationships among microbes. Subsequent focus on functional genes, those that encode enzymes that catalyze biogeochemical transformations, and current work on larger DNA fragments and entire genomes make it possible to link microbial diversity to ecosystem function. These approaches have yielded insights into the regulation of microbial activity and proof of the microbial role in biogeochemical processes previously unknown. Questions raised by the molecular revolution, which are now the focus of microbial ecology research, include the significance of microbial diversity and redundancy to biogeochemical processes and ecosystem function.
Effects of recombinant human follicle-stimulating hormone on embryo development in mice
Authors: Edwards L. J. , Kind K. L. , Armstrong D. T. , Thompson J. G.
Published: December 2004

We have developed a protocol using recombinant human follicle-stimulating hormone (rhFSH) to induce ovarian stimulation in the mouse to investigate its impact on preimplantation embryo development. Embryos were collected from adult female C57Bl/6 × CBA F1 mice treated with rhFSH (0, 2.5, 5.0, 10.0, or 20.0 IU) or 5 IU equine chorionic gonadotropin (eCG). Embryos were also recovered from nontreated control mice. Embryos were cultured in vitro for 88 h, and the stage of development was morphologically assessed. The allocation of cells to the inner cell mass or trophectoderm of blastocysts was determined by differential nuclear staining. The expression of insulin-like growth factor 2 (IGF-II), the insulin-like growth factor receptor (IGF-II receptor), and vascular endothelial growth factor (VEGF) in blastocysts was measured by real-time RT-PCR. Blastocyst development was reduced in the 10 (72.3 ± 5.1%) and 20 (77.3 ± 5.6%) IU rhFSH groups compared with control embryos (96.7 ± 1.0%). The number of inner cell mass cells was reduced ( P < 0.001) in the 5, 10, and 20 IU rhFSH groups and the eCG group compared with control embryos. We did not find any effect of rhFSH treatment on IGF-II, IGF-II receptor, or VEGF expression in blastocysts compared with the control group. eCG treatment, however, significantly increased the expression of IGF-II in blastocysts. These results indicate that ovarian stimulation with rhFSH impairs the in vitro development of preimplantation mouse embryos, and these results may have potential implications for clinical ovarian stimulation during infertility treatment and subsequent embryo quality.
Hyperthyroidism and cation pumps in human skeletal muscle
Authors: Riis Anne Lene Dalkjær , Jørgensen Jens Otto Lunde , Møller Niels , Weeke Jørgen , Clausen Torben
Published: December 2004

Skeletal muscle constitutes the major target organ for the thermogenic action of thyroid hormone. We examined the possible relation between energy expenditure (EE), thyroid status, and the contents of Ca2+-ATPase and Na+-K+-ATPasein human skeletal muscle. Eleven hyperthyroid patients with Graves' disease were studied before and after medical treatment with methimazole and compared with eight healthy subjects. Muscle biopsies were taken from the vastus lateralis muscle, and EE was determined by indirect calorimetry. Before treatment, the patients had two- to fivefold elevated total plasma T3 and 41% elevated EE compared with when euthyroidism had been achieved. In hyperthyroidism, the content of Ca2+-ATPase was increased: (mean ± SD) 6,555 ± 604 vs. 5,212 ± 1,580 pmol/g in euthyroidism ( P = 0.04) and 4,523 ± 1,311 pmol/g in healthy controls ( P = 0.0005). The content of Na+-K+-ATPase showed 89% increase in hyperthyroidism: 558 ± 101 vs. 296 ± 34 pmol/g ( P = 0.0001) in euthyroidism and 278 ± 52 pmol/g in healthy controls ( P < 0.0001). In euthyroidism, the contents of both cation pumps did not differ from those of healthy controls. The Ca2+-ATPase content was significantly correlated to plasma T3 and resting EE. This provides the first evidence that, in human skeletal muscle, the capacity for Ca2+ recycling and active Na+-K+ transport are correlated to EE and thyroid status.
Bilateral Processing of Motor Commands in the Motor Cortex of the Cat During Target-Reaching
Authors: Perfiliev S.
Published: December 2004

Single-unit activity of the motor cortex (area 4γ) was studied in cats performing reaching with the contra- versus ipsilateral forelimb. Reaching was initiated by a tone burst (Go cue), different limbs were used in separate blocks of trials. During reaching performed with the contralateral limb, three types of neurons were observed. The first type had biphasic pattern with an initial component locked to the Go cue followed by a component locked to the onset of reaching. The second type of neurons had monophasic discharges correlated both with the onset of the stimulus and with the movement. The third type showed responses related to the movement. Activity of the same cells investigated during reaching performed with the ipsilateral limb revealed that the cue-locked responses of the cells of the first type were effector independent, i.e., similar discharges locked to the Go cue were generated. The movement-related component of these cells was drastically reduced. The activity of some cells of the second type was suppressed during reaching with the ipsilateral limb. When performance was switched between limbs, a significant change of background discharge frequency was observed in 31% of the cells. The present results suggest that the sensory cue triggers elaboration of motor commands for reaching in both motor cortices, but further sensorimotor transformation is completed in only one hemisphere but is aborted actively in the other. It is also suggested that a certain pattern of background activity may serve a tuning function for elaboration of the command in the proper hemisphere.
A Multi-Channel, Implantable Microdrive System for Use With Sharp, Ultra-Fine “Reitboeck” Microelectrodes
Authors: Swadlow Harvey A. , Bereshpolova Yulia , Bezdudnaya Tatiana , Cano Monica , Stoelzel Carl R.
Published: December 2004

Arrays of closely spaced quartz-insulated, platinum-tungsten microelectrodes are widely used to obtain acute recordings from chronically prepared subjects. These electrodes have excellent recording characteristics and can be fabricated to a wide variety of tip specifications. Typically, in such experiments, electrodes are introduced into, and removed from, the brain on a daily basis and, over many months of study, hundreds of penetrations may be made through an intact dura. This procedure has benefits as well as problems and risks. For some experimental aims, it might be desirable to leave the microelectrodes within the brain so that the penetrations could be continued on subsequent days. This would allow a more thorough and systematic exploration of the neurons that lie along the trajectory of each of the closely aligned electrodes and would minimize risks and preparation time associated with daily electrode insertions. Here we present a means for achieving this aim using arrays of sharp, flexible Reitboeck electrodes of extremely fine diameter (40-μm shaft diameter, pulled and ground to a fine tip). We show that these electrodes retain their excellent recording characteristics and can remain under microdrive control within the brain for periods of many months and, in one remarkable case, for >4 years.
Subtype Composition and Responses of Respiratory Neurons in the Pre-Bötzinger Region to Pulmonary Afferent Inputs in Dogs
Authors: Krolo M. , Tonkovic-Capin V. , Stucke A. G. , Stuth E. A. , Hopp F. A. , Dean C. , Zuperku E. J.
Published: December 2004

The brain stem pre-Bötzinger complex (pre-BC) plays an important role in respiratory rhythm generation. However, it is not clear what function each subpopulation of neurons in the pre-BC serves. The purpose of the present studies was to identify neuronal subpopulations of the canine pre-BC and to characterize the neuronal responses of subpopulations to experimentally imposed changes in inspiratory (I) and expiratory (E) phase durations. Lung inflations and electrical stimulation of the cervical vagus nerve were used to produce changes in respiratory phase timing via the Hering-Breuer reflex. Multibarrel micropipettes were used to record neuronal activity and for pressure microejection in decerebrate, paralyzed, ventilated dogs. The pre-BC region was functionally identified by eliciting tachypneic phrenic neural responses to localized microejections of dl-homocysteic acid. Antidromic stimulation and spike-triggered averaging techniques were used to identify bulbospinal and cranial motoneurons, respectively. The results indicate that the canine pre-BC region consists of a heterogeneous mixture of propriobulbar I and E neuron subpopulations. The neuronal responses to ipsi-, contra-, and bilateral pulmonary afferent inputs indicated that I and E neurons with decrementing patterns were the only neurons with responses consistently related to phase duration. Late-I neurons were excited, but most other types of I neurons were inhibited or unresponsive. E neurons with augmenting or parabolic discharge patters were inhibited by ipsilateral inputs but excited by contra- and bilateral inputs. Late-E neurons were more frequently encountered and were inhibited by ipsi- and bilateral inputs, but excited by contralateral inputs. The results suggest that only a limited number of neuron subpopulations may be involved in rhythmogenesis, whereas many neuron types may be involved in motor pattern generation.
Valproate-induced alterations in human theca cell gene expression: clues to the association between valproate use and metabolic side effects
Authors: Wood Jennifer R. , Nelson-Degrave Velen L. , Jansen Erik , McAllister Jan M. , Mosselman Sietse , Strauss Jerome F.
Published: December 2004

Valproic acid (VPA) is an anti-epileptic drug that has been associated with polycystic ovary syndrome (PCOS)-like symptoms, including increased ovarian androgen production. The hyperandrogenemia likely reflects the stimulatory action of VPA on theca cell androgen synthesis and has been correlated to its activity as a histone deacteylase inhibitor in these cells. To determine whether VPA induces a PCOS-like genomic phenotype, we compared the gene expression profiles of untreated (UNT) normal, VPA-treated normal, and UNT PCOS theca cells. Hierarchal cluster analysis demonstrated similarities in the gene expression profiles of VPA-treated normal and PCOS theca cells. Statistical analysis identified 1,050 transcripts that have significantly altered mRNA abundance in both VPA-treated normal and UNT PCOS theca cells compared with normal UNT theca cells. Among these 1,050 transcripts were cAMP-GEFII and TRB3, which have increased and decreased mRNA abundance, respectively. The altered abundance of these two mRNAs was correlated to increased basal and insulin-induced phosphorylation of protein kinase B (Akt/PKB). Thus these studies indicate that VPA- and PCOS-induced changes in gene expression enhance Akt/PKB signal transduction in human theca cells. Furthermore, common changes in gene expression in PCOS and VPA-treated normal theca cells suggest a possible mechanism for the development of PCOS-like symptoms, including increased steroid synthesis and arrested follicle development in women receiving chronic VPA therapy.
Shifted quadratic Zeta series
Authors: Sofo Anthony
Published: December 2004

It is well known that the Riemann Zeta function can be represented in closed form for p an even integer. We will define a shifted quadratic Zeta series as . In this paper, we will determine closed‐form representations of shifted quadratic Zeta series from a recursion point of view using the Riemann Zeta function. We will also
determine closed‐form representations of alternating sign shifted quadratic Zeta series.
An index formula for the degree of (S)+‐mappings associated with one‐dimensional p‐Laplacian
Authors: Kobayashi Jun , Ôtani Mitsuharu
Published: December 2004

The topological degree for (S)+‐mappings concerning a nonlinear eigenvalue problem associated with one‐dimensional p‐Laplacian is evaluated. The result is applied to a variational inequality, where the multiple existence of solutions is discussed.
A Pragmatic, Co-operative Approach To Teaching Environmental Ethics
Authors: Shapiro Daniel , Takacs David
Published: December 2004

Our pragmatic, cooperative approach to teaching environmental ethics at California State University Monterey Bay nurtures students' moral development in both their public and private realms by putting into practice three principles. First, to propose what "we ought to do," students must first think deeply about what " I ought to do." Second, adequately justifying what "I ought to do" and what "we ought to do" requires that students acknowledge, understand, and respect differing perspectives. Third, a course that does not advocate for a particular environmental ethic enhances rather than inhibits students' moral development. This paper describes how—and why—we have designed our course in accordance to these three principles.
Evaluation of First‐Pass Cytochrome P4503A (CYP3A) and P‐Glycoprotein Activities Using Alfentanil and Fexofenadine in Combination
Authors: Kharasch Evan D. , Walker Alysa , Hoffer Christine , Sheffels Pamela
Published: December 2004

Cytochrome P4503A (CYP3A) and P‐glycoprotein (P‐gp) are major determinants of oral bioavailability. Development of in vivo probe(s), for both CYP3A and P‐gp, which could be administered in combination, is a current goal. Nevertheless, there is considerable overlap in CYP3A and P‐gp substrate selectivities; there are few discrete probes. Alfentanil is a selective CYP3A probe but not a P‐gp substrate. Fexofenadine is a P‐gp probe but not a CYP3A substrate. This investigation tested the hypothesis that alfentanil and fexofenadine could be administered in combination to probe first‐pass CYP3A and P‐gp activities in humans. Two 3‐way crossover studies were conducted in healthy volunteers. In the first protocol, subjects received oral alfentanil alone, fexofenadine alone, or fexofenadine 1 hour after alfentanil. In the second protocol, subjects abstained from citrus and apple products for 5 days and received fexofenadine alone, fexofenadine 1 hour after alfentanil, or alfentanil 4 hours after fexofenadine. An assay using solid‐phase extraction and electrospray liquid chromatography/mass spectrometry was developed for the simultaneous quantification of plasma alfentanil and fexofenadine. In both protocols, alfentanil plasma concentrations and area under the concentration versus time curve (AUC) were unaffected by fexofenadine or meal composition. Fexofenadine given 1 hour after alfentanil and followed 1 hour later by a meal containing orange or apple juice had a somewhat lower AUC compared with fexofenadine alone (geometric mean ratio with and without the interacting drug = 0.73, 90% confidence interval [CI] = 0.59–1.04). Fexofenadine given 1 hour after alfentanil and followed 2 hours later by a meal not containing citrus or apple products had an AUC that was unchanged compared with fexofenadine alone (ratio = 0.91, 90% CI = 0.70–1.35). These results show that alfentanil disposition was not affected by fexofenadine. A dosing regimen was identified in which fexofenadine disposition was not affected by alfentanil. The timing and content of meals after fexofenadine had a significant effect on fexofenadine disposition. Alfentanil and fexofenadine in combination appear to be a useful probe for evaluating both first‐pass CYP3A and P‐gp activities in humans.
Critical Differences Among Beta‐Adrenoreceptor Antagonists in Myocardial Failure: Debating the MERIT of COMET
Authors: McBride Brian F. , White C. Michael
Published: December 2004

In the United States, carvedilol and metoprolol (tartrate or succinate) are the most commonly employed beta‐adrenoreceptor antagonists for the treatment of heart failure. However, use of these agents in patients with heart failure remains extremely low despite overwhelming evidence of their beneficial short‐ and long‐term effects. Because the myocardial pathophysiology associated with heart failure involves not only β‐1 adrenoreceptors but also β‐2 and α‐1 adrenoreceptors, this indicates a more complex disease process that may require pan‐receptor antagonism to provide optimal clinical benefit. Relative to metoprolol (tartrate or succinate), carvedilol represents an extremely complex molecular entity that not only possesses the ability to antagonize all of the principle adrenoreceptors involved in heart failure but also reduces oxidative stress and provides an antiarrhythmic benefit independent of beta‐adrenoreceptor antagonism. Taken together, an interesting pharmacologic premise for the superiority of carvedilol relative to metoprolol (tartrate) may exist, but the lack of clinical trials comparing an optimal dose of either extended‐release metoprolol (ie, succinate) or immediate‐release metoprolol (ie, tartrate) to carvedilol limits the clinical application of the pharmacologic differences between the agents.
Microstructural Origin of Strength and Toughness of Epoxy Nanocomposites
Authors: Ganguli Sabyasachi , Aglan Heshmat , Dean Derrick
Published: December 2004

Nanocomposites of a bifunctional epoxy resin are synthesized and evaluated. Organically modified layered silicate (OLS) particles (4% by weight) and multiwalled carbon nanotubes (MWNT) (1% by weight) are used as reinforcements. Thermal and viscoelastic characterization of the two composites are performed and compared with the neat resin. Tensile tests are conducted on multiple identical unnotched and notched specimens to evaluate the overloading and fracture behavior of the nanocomposites. In comparison with the neat bifunctional epoxy, it is found that the 1% MWNT reinforcement increased the ultimate strength and strain to failure by about 139 and 158%, respectively. In comparison, the OLS has increased the ultimate strength and strain by about 30 and 20%, respectively. In comparison with the neat resin, there is a 170% increase in the fracture toughness of the MWNT composites and only 17% in the case of the OLS composites. Fracture surface analysis revealed the various mechanisms by which the MWNT composites acquire their superior strength and toughness in comparison with the neat resin.
Goal orientation, implicit theory of ability, and collegiate instrumental music practice
Authors: Smith Bret P.
Published: December 2004

The purposes of this study were twofold: to examine the relationship of two types of motivational belief to undergraduates’ self-reported musical practice behavior, and to evaluate the adaptation of measures of academic motivation to the musical domain. Measures of a tripartite goal orientation and implicit theory of musical ability were completed by 344 instrumental music majors at American universities. Factor analysis showed the adapted items reproduced the subscales of the original measures, and that these subscales were reliable (α > .74). Entity theories of musical ability were positively correlated with ego-approach ( r = .16, p < .01) and ego-avoid goals ( r = .23, p < .001), and negatively related to task goals ( r = -.14, p <.01). A researcher-designed practice strategy survey found task orientation positively related to frequency of six of seven practice factors; ego-approach and ego-avoid goals negatively related to one strategy type.
Fatigue Characteristics of a Surface Antenna Structure Designed for Satellite Communication
Authors: Kim D. H. , Hwang W. , Park H. C. , Park W. S.
Published: December 2004

Our objective in this work was to design a Surface Antenna Structure (SAS) for satellite communication and investigate the fatigue behavior of an asymmetric sandwich structure (SAS). The term, SAS indicates that a structural surface itself acts as an antenna. Constituent materials were selected for their electrical properties, dielectric constant, and tangent loss as well as mechanical properties. Antenna elements were inserted into structural layers to create a multilayer microstrip array antenna. Electrical measurements showed that antenna performance was in good agreement with the design specifications. Under cyclic four-point bending, the flexure behavior was investigated by static and fatigue testing. The fatigue life curve of the SAS was obtained. These experimental results were then compared with several single load level fatigue life prediction equations (SFLPE), and good agreement was found. The SAS concept is the first serious attempt at integration of antenna and composite engineering and promises to be an innovative future communication technology.
Thermal Shock and Thermal Fatigue on Delamination of Glass-fiber-reinforced Polymeric Composites
Authors: Ray B. C.
Published: December 2004

Glass-fiber-reinforced unsaturated polyester and epoxy resin composites were exposed to 75°C temperature gradient thermal shock for ten times in different stages of conditioning times. The other lot of short-beam shear specimens were conditioned with a thermal shock of again 75°C temperature gradient for the different cycles. The three-point bend test was performed on the conditioned specimens to evaluate the value of interlaminar shear strength. These conditionings may induce matrix cracking because of large misfit strain. The present experiments aim to study the fiber-matrix debonding effect of thermal shock-thermal fatigue, post-curing hardening phenomena of thermal conditioning, and also the mechanical keying factor of sub-zero conditioning.
Effect of Red Phosphorus and Melamine Polyphosphate on the Fire Behavior of HIPS
Authors: Braun Ulrike , Schartel Bernhard
Published: December 2004

Pyrolysis and fire behavior of high impact polystyrene (HIPS) containing red phosphorus and melamine polyphosphate were investigated. The thermal and thermo-oxidative decomposition were characterized using thermogravimetry coupled with FTIR and MS, respectively. The fire behavior was monitored with a cone calorimeter using different external heat fluxes and determining the LOI. Red phosphorus reduced the heat release in HIPS due to radical trapping in the gas phase. The reduction in effective heat of combustion was accompanied by an increase of incomplete combustion products such as smoke and carbon monoxide. Melamine polyphosphate in HIPS acted in the condensed phase with barrier formation. The heat release rate was reduced, whereas the total heat evolved, smoke and carbon monoxide formation were not influenced significantly. Using both fire retardants, the resulting fire retardancy was characterized mainly by superposition.
Women, Love, and Intimacy “Gone Wrong”: Fire, Wind, and Ice
Authors: Fraser Heather
Published: December 2004

Although questions about why so many women “love to love” and why some stay with abusive lovers may seem clichéd, they are questions over which many people still muse. Using a collage of ideas drawn from a wide range of sources, including 83 narrative feminist interviews that were conducted from 2000 to 2004, I respond to these questions, trying to show some of the inducements that are made to women to love others. The simulated diary entries of one (composite) woman suggest that as many women enter monogamous coupledom, there are unexpected (but all too common) problems of intimacy.
Trends in Understanding and Addressing Domestic Violence
Authors: Mears Daniel P. , Visher Christy A.
Published: December 2004

This article is a response to three questions posed by the editor about past and future research on interpersonal violence by focusing in this essay on domestic violence:(a) What is the most important thing we have learned about this social problem in the last 20 years, (b) what is the most important thing we need to learn about it in the next 10 years, and (c) what is the most promising methodological innovation in the last 20 years for the study or treatment of domestic violence? This assessment suggests that the field has witnessed considerable advances in domestic violence research and policy but that many as yet untapped opportunities exist to improve both knowledge and practice.
Issues in Violent Risk Assessment
Authors: Kroner Daryl G.
Published: December 2004

Realizing that the assessment of dangerousness with a yes/no format as a poor form of violent risk assessment has been the most important lesson learned about violence in the last 20 years. Further examining (a) what outcome and (b) how the indicators of the outcome should be measured has resulted in better violent risk assessment. The most promising methodological innovation in violent risk assessment has been the introduction of the receiver operating characteristic to assess the efficiency of risk prediction. In the future, the tension between prediction and explanation of violence will need to be maintained while focusing on a mechanism-driven strategy of risk management.
20 Years of Research into Violence and Trauma
Authors: Kamphuis Jan H. , Emmelkamp Paul M. G.
Published: December 2004

This reflection on major developments in the past, present, and future of the wider field of violence and trauma is a personal (and probably biased) sampling of what the authors hold to be important. The authors reviewed advances for victims and perpetrators of violence separately. For victims, the authors note that empirical research has established the potential traumatic impact of violence as well as various predictors of what makes persons vulnerable to adverse psychological consequences. The authors also note that the definitions of violence and trauma have evolved to include such behavioral patterns as stalking. Finally, encouraging evidence regarding the efficacy of exposure-based treatments for victims of violence is reviewed, as well as discouraging evidence regarding the efficacy of single-session debriefing following trauma. For the perpetrators, the importance of individual assessment in planning interventions is underscored, and advances in explicit and implicit assessment techniques are discussed.
Pain Disability Among Older Adults With Arthritis
Authors: James Nadine T. , Miller Carl W. , Brown Kathleen C. , Weaver Michael
Published: December 2004

Objective: The principal objective was to examine pain disability (the degree to which chronic pain interferes with daily activities) among older adults with arthritis. Specifically, answers to two research questions were sought: (a) Does psychological distress reliably predict pain disability; and (b) do certain theoretically important host, sociodemographic, and health-related factors reliably predict pain disability? Method: Descriptive, univariate, and multivariate regression analyses were employed to assess key psychosocial, disease, and host factors among the sample ( N =141) of adults with arthritis, aged [UNKNOWN] 50 years old. Results: The resultant regression model accounted for 63.7% (60.0% adjusted) of the variance and was significant at p < .01. Psychological distress, overall health, disease activity, and disease self-efficacy were found to predict pain disability. Discussion: Sample members with greater pain disability experienced heightened psychological distress, poorer perceptions of their overall health, more surgeries, higher unemployment, more intense disease activity, longer disease duration, and lower disease self-efficacy.
Effects of Gender, Ethnicity, and Medical Illness on Drinking Cessation in Older Primary Care Patients
Authors: Satre Derek D. , Areán Patricia A.
Published: December 2004

Objective: This study examined the effects of gender, ethnicity, and medical illness on cessation of alcohol consumption in late life by analyzing characteristics that distinguish current drinkers from former drinkers. Method: Participants were 211 medical patients aged 55 to 91 years, recruited from four urban public sector primary care clinics. Respondents completed the Short Michigan Alcohol Screening Test and provided health and demographic data. A subset ( n = 139) reported drinking history. Of these participants, 40% reported cessation of alcohol consumption at least 1 year prior to their participation in the study. Results: Older age, hypertension, and heart problems were associated with drinking cessation among women but not among men. In a logistic regression model, drinking cessation was predicted by being unmarried, being a member of an ethnic minority group, heart problems, and diabetes. Discussion: Physical illnesses may contribute to drinking cessation, especially in older women. Results have implications for alcohol interventions with older adults.
A Planning Framework for Crafting the Required-Curriculum Phase of an MBA Program
Authors: Haskins Mark E.
Published: December 2004

This article introduces a planning framework for designing that part of an MBA program during which students take the bulk, if not all, of their required courses. The framework highlights three student venues that can be jointly leveraged for enhanced student learning. Those venues are the required curriculum, students’ affinity groups, and the career-related searches that they pursue. For each venue, the framework links three program design foci. These design foci are balance and pace, for sustaining student interest and effort; integration, for leveraging expanded and reinforced learning opportunities; and standards, for the quality design and delivery of the program components. Numerous specific practices used to plan and deliver the required-curriculum phase of the University of Virginia’s Darden Graduate School MBA program are also presented.
Frequency Response of a Piecewise Linear Vibration Isolator
Authors: Narimani A. , Golnaraghi M. E. , Jazar G. Nakhaie
Published: December 2004

Piecewise linear vibration isolators are designed to optimally balance the competing goals of motion control and isolation. The piecewise linear system represents a hard nonlinearity, which cannot be assumed small, and hence standard perturbation methods are unable to provide a complete analytical solution. To date there is no frequency response equation reported for piecewise linear isolator systems to include both dual damping and stiffness behavior. In this investigation an averaging method was adopted to explore the frequency response of a symmetric piecewise linear isolator at resonance. The result obtained by an averaging method is in agreement with numerical simulation and experimental measurements. Preliminary sensitivity analysis is conducted to find the effect of system parameters. It appears that the damping ratio plays a more dominant role than stiffness in piecewise linear vibration isolators.
TANF Workers’ Responses to Battered Women and the Impact of Brief Worker Training
Authors: Saunders Daniel G. , Holter Mark C. , Pahl Lisa C. , Tolman Richard M. , Kenna Colleen E.
Published: December 2004

Battered women (n = 159) report on their experiences with their Temporary Assistance to Needy Families (TANF) case workers. Workers most often ask about physical harm, feelings of fear, and police involvement. They least often create a safety plan, give information about work exemptions, and ask whether the partner had a gun. Women’s major reasons for not talking about abuse are that the worker did not ask and a fear of negative outcomes. Workerswho attendeda 1-day training are more likely than untrained workers to discuss the women’s fear and physical harm, to help develop a safety plan, and to be viewed as generally helpful.
Note: Fractionation of Sheep Milk Fat Via Supercritical Carbon Dioxide
Authors: Spano V. , Salis A. , Mele S. , Madau P. , Monduzzi M.
Published: December 2004

Supercritical carbon dioxide (SC-CO2) was used for anhydrous ovine milk fat (AMF) fractionation. Two different fractions were obtained: a low molecular weight triacylglycerol (TAG), named fraction E, and a high molecular weight TAG, termed fraction R. Fractionation was performed at different pressure and temperature values. The effect of these parameters on the chemical composition of the two fractions were analysed in relation to the original AMF. Among the searched conditions, 250 bar and 40°C gave the best fractionation results.
Localized Effects in the Nonlinear Behavior of Sandwich Panels with a Transversely Flexible Core
Authors: Frostig Yeoshua , Thomsen Ole Thybo
Published: December 2004

This paper presents the results of an investigation of the role of localized effects within the geometrically nonlinear domain on structural sandwich panels with a “compliant” core. Special emphasis is focused on the nonlinear response near concentrated loads and stiffened core regions. The adopted nonlinear analysis approach incorporates the effects of the vertical flexibility of the core, and it is based on the approach of the High-order Sandwich Panel Theory (HSAPT). The results demonstrate that the effects of localized loads, when taken into the geometrically nonlinear domain, change the response of the panel from a strength problem controlled by stress constraints into a stability problem with unstable limit point behavior when force-controlled loads are applied. The stability problem emerge as the nonlinear response develops with the formation of a small number of buckling waves in the compressed face sheet in the vicinity of the localized loads. The development of the nonlinear response is demonstrated through the numerical study of three-point bending of a unidirectional sandwich panel with an unstiffened core, and with a core stiffened in the vicinity of the loads, respectively. It is shown, that the change from unstiffened to stiffened core alters the nonlinear response significantly. The nonlinear response is described in terms of deflections and stress resultants in the face sheets, as well as in terms of the interfacial stress components at the upper and lower face–core interfaces. The overall nonlinear response is described through curves of the load versus the extreme absolute values of the aforementioned structural quantities. A very important finding of the study is that stiffening of the core may improve the performance in terms of local stresses to some extent, but at the same time it may lead to undesirable bifurcation-type or semi elastoplastic behavior in some cases.
When Nationality Matters
Authors: Zander Lena , Romani Laurence
Published: December 2004

The objective of the study presented in this article is to answer the question of when nationality matters regarding employees’ interpersonal leadership preferences. Based on a literature review, 16 tenure- and demographic-based groupings of employees (four departments, five work positions, five age groups and gender) were identified. Hypotheses were developed regarding whether employee group-based belonging overrides nationality-based belonging. These were tested across 15 countries and could be rejected for almost all groups due to significant differences in leadership preferences. Although the results concerning three employee groupings: researchers, supervisors and ‘over 55-years-old’ were inconclusive, it was not possible to identify one specific employee grouping that overrode nationality-based belonging. These results contribute to earlier research by refuting the often argued notion that departments, hierarchical work positions, professions, age groups and gender are categories of employees that should be managed as distinct groups with similar leadership preferences across country borders.
Balance of MafB and PU.1 specifies alternative macrophage or dendritic cell fate
Authors: Bakri Youssef , Sarrazin Sandrine , Mayer Ulrich P. , Tillmanns Silke , Nerlov Claus , Boned Annie , Sieweke Michael H.
Published: December 2004

Macrophages and myeloid dendritic cells (DCs) represent alternative differentiation options of bone marrow progenitors and blood monocytes. This choice profoundly influences the immune response under normal and pathological conditions, but the underlying transcriptional events remain unresolved. Here, we show that experimental activation of the transcription factors PU.1 and MafB in transformed chicken myeloid progenitors triggered alternative DC or macrophage fate, respectively. PU.1 activation also was instructive for DC fate in the absence of cytokines in human HL-60 cell-derived myeloid progenitor and monocyte clones. Differentiation of normal human monocytes to DCs led to a rapid increase of PU.1 to high levels that preceded phenotypic changes, but no MafB expression, whereas monocyte-derived macrophages expressed MafB and only moderate levels of PU.1. DCs inducing levels of PU.1 inhibited MafB expression in monocytes, which appeared to be required for DC specification, since constitutive MafB expression inhibited DC differentiation. Consistent with this, PU.1 directly bound to MafB, inhibited its transcriptional activity in macrophages, and repressed its ability to induce macrophage differentiation in chicken myeloid progenitors. We propose that high PU.1 activity favors DCs at the expense of macrophage fate by inhibiting expression and activity of the macrophage factor MafB.
Gonadotropin-Induced Δ14-Reductase and Δ7-Reductase Gene Expression in Cumulus Cells during Meiotic Resumption of Porcine Oocytes
Authors: Yamashita Yasuhisa , Nishibori Masahide , Terada Takato , Isobe Naoki , Shimada Masayuki
Published: December 2004

Progesterone is produced from cholesterol in cumulus cells during meiotic resumption of porcine oocytes. In follicular cells, it has been shown that exogenous lipoprotein-bound cholesterol ester can be used for steroid hormone production. However, in serum-free medium, progesterone is also secreted by FSH- and LH-stimulated cumulus-oocyte complexes, suggesting that progesterone could be produced from de novo synthesized cholesterol in cumulus cells. In the present study, we investigated the expression of Δ14-reductase and Δ7-reductase, which are the members of the superfamily that converts acetyl-CoA to cholesterol in cumulus cells. The expression of both genes was analyzed by RT-PCR. Both Δ14-reductase mRNA and Δ7-reductase mRNA in cumulus cells, cultured until 4 h, were under the level of detection limit. In response to gonadotropins, both mRNA levels were dramatically up-regulated, reaching a maximum at 20 h. To clarify the role of induced enzymes in cumulus cells, cumulus-oocyte complexes were cultured with either Δ14-reductase inhibitor, AY9944-A-7, or Δ7-reductase inhibitor, BM15.766. The results indicated that these inhibitors significantly suppressed the progesterone production in cumulus cells and meiotic progression of oocytes. The inhibitory effects reached a maximum at 1 μm AY9944-A-7 or 20 μm BM15.766. The addition of 20 ng/ml progesterone overcame the inhibitory effects of both drugs on meiotic resumption of oocytes. These results imply that gonadotropin-induced expression and function of Δ14-reductase and Δ7-reductase in cumulus cells contribute to oocyte meiotic resumption via a progesterone-dependent pathway.
Regulation of Luteinizing Hormone/Chorionic Gonadotropin Receptor Messenger Ribonucleic Acid Expression in the Rat Ovary: Relationship to Cholesterol Metabolism
Authors: Wang Lei , Menon K. M. J.
Published: December 2004

Down-regulation of LH/human chorionic gonadotropin (hCG) receptor (LHR) mRNA in the ovary after the preovulatory LH surge or the administration of a pharmacological dose of LH/hCG occurs through a posttranscriptional mechanism. A LHR mRNA-binding protein was identified as the LHR mRNA destabilizing factor, and its identity was established as mevalonate kinase (Mvk). In the present study, we determined that, in the pseudopregnant rat ovary, LHR mRNA levels began to fall 4 h after hCG injection, at which time Mvk protein levels were elevated, and this elevation was preceded by an increase in Mvk mRNA levels. When the cytosolic fractions of hCG-treated ovaries were subjected to RNA EMSA, an increase in LHR mRNA-LHR mRNA-binding protein complex formation was observed, in parallel with the increase of Mvk expression. We also found that hCG coordinately up-regulated the expression of Mvk and other sterol-responsive elements containing cholesterol biosynthesis enzymes, such as 3-hydroxy-3-methylglutaryl-coenzyme A synthase, 3-hydroxy-3-methylglutaryl-coenzyme A reductase, and farnesyl pyrophosphate synthase. This up-regulation was transient, but the hCG-induced ovarian cholesterol depletion lasted for more than 24 h. Taken together, our results suggest that, in the ovary, LH/hCG up-regulates the expression of cholesterol biosynthesis enzymes and lipoprotein receptors to replenish cellular cholesterol, and the up-regulation of Mvk leads to a down-regulation of LHR and suppresses the LH/hCG signal cascade transiently. Thus Mvk, an enzyme involved in cholesterol biosynthesis, serves as a link between LHR mRNA expression and cellular cholesterol metabolism.
Activation of Peroxisome Proliferator-Activated Receptor-γ and Retinoid X Receptor Inhibits Aromatase Transcription via Nuclear Factor-κB
Authors: Fan WuQiang , Yanase Toshihiko , Morinaga Hidetaka , Mu Yi-Ming , Nomura Masatoshi , Okabe Taijiro , Goto Kiminobu , Harada Nobuhiro , Nawata Hajime
Published: December 2004

Our previous studies demonstrated that a peroxisome proliferator-activated receptor (PPAR)-γ ligand, troglitazone (TGZ),and/or a retinoid X receptor (RXR) ligand, LG100268 (LG), decreased the aromatase activity in both cultured human ovarian granulosa cells and human granulosa-like tumor KGN cells. In the present study, we further found that a combined treatment of TGZ+LG decreased aromatase promoter II (ArPII) activity in both ovarian KGN cells and fibroblast NIH-3T3 cells in a PPARγ-dependent manner. Furthermore, the inhibition of both aromatase activity and the transcription of ArPII by TGZ+LG was completely eliminated when nuclear factor-κB (NF-κB) signaling was blocked by specific inhibitors, suggesting NF-κB, which is endogenously expressed in both fibroblast and granulosa cells, might be a mediator of this inhibition. Interestingly, activation of NF-κB by either forced expression of the p65 subunit or NF-κB-inducing kinase up-regulated ArPII activity. Positive regulation of aromatase by endogenous NF-κB was also suggested by the fact that NF-κB-specific inhibitors suppress basal activity of the aromatase gene. A concomitant formation of high-order complex between NF-κB p65 and ArPII was also observed by chromatin immunoprecipitation assay. Although activation of PPARγ and RXR affected endogenous expression levels of neither inhibitory κBα nor p65, it impaired the interaction between NF-κB and ArPII and the p65 based transcription as well. Altogether, these results indicate that activation of a nuclear receptor system, constituted by PPARγ and RXR, down-regulates aromatase expression through the suppression of NF-κB-dependent aromatase activation and thus provide a new insight in the mechanism of regulation of the aromatase gene.
Inhibition of Nox-4 activity by plumbagin, a plant-derived bioactive naphthoquinone
Authors: Ding Yaxian , Chen Zi-Jiang , Liu Shiguo , Che Danian , Vetter Michael , Chang Chung-Ho
Published: December 2004

NAD(P)H oxidase contributes to the pathogenesis of cancer and cardiovascular diseases such as hypertension, atherosclerosis, restenosis, cardiac hypertrophy and heart failure. Plumbagin, a plant-derived naphthoquinone, has been shown to exert anticarcinogenic and anti-atherosclerosis effects in animals. However, the molecular mechanisms underlying these effects remain unknown. It is possible that the beneficial effect of plumbagin is due to the inhibition of NAD(P)H oxidase. Human embryonic kidney 293 (HEK293) and brain tumour LN229 cells express mainly Nox-4, a renal NAD(P)H oxidase. We have examined the effect of plumbagin on Nox-4 activity in HEK293 and LN229 cells using lucigenin-dependent chemiluminescence assay. Plumbagin inhibited the activity of Nox-4 in a time- and dose-dependent manner in HEK293 and LN229 cells. Production of superoxide in HEK293 cells was inhibited by diphenyleneiodonium (DPI), a NAD(P)H oxidase inhibitor. The superoxide production in HEK293 cells was NADPH- and NADH-dependent indicating that the superoxide was generated by a NAD(P)H oxidase in HEK293 cells, but not by the redox-cycling of lucigenin. Furthermore, plumbagin inhibited the superoxide production in Nox-4 transfected COS-7 cells. These results indicated that plumbagin directly interacted with Nox-4 and inhibited its activity.