bluuebunny/crossref_metadata_2025 huggingface dataset:
SEGREGATION OF FLUIDIZED BINARY HARD-SPHERE SYSTEMS UNDER GRAVITY
Authors: KIM SOON-CHUL
Published: April 2005

We have derived an analytic expression for the contact value of the local density of binary hard-sphere systems under gravity. We have obtained the crossover conditions for the Brazil-nut type segregation of binary hard-sphere mixtures and binary hard-sphere chain mixtures from the segregation criterion, where the segregation occurs when the density (or the pressure) of the small spheres at the bottom is higher than that of the large spheres, or vice versa. For the binary hard-sphere chain mixtures, the crossover condition for the segregation depends on the number of monomers composed of hard-sphere chains as well as the mass and the diameter of each species. The fundamental-measure theories (FMTs) and local density approximation (LDA) are employed to examine the crossover condition for the segregation of the gravity-induced hard-sphere mixtures. The calculated results show that the LDA does not explain the density oscillation near the bottom, whereas the modified fundamental-measure theory (MFMT) compares with molecular dynamics simulations.
Oligomycin inhibits HIF-1α expression in hypoxic tumor cells
Authors: Gong Yanqing , Agani Faton H.
Published: April 2005

Hypoxia-inducible factor-1 (HIF-1) is a key regulator of cellular responses to reduced oxygen availability. The contribution of mitochondria in regulation of HIF-1α in hypoxic cells has received recent attention. We demonstrate that inhibition of electron transport complexes I, III, and IV diminished hypoxic HIF-1α accumulation in different tumor cell lines. Hypoxia-induced HIF-1α accumulation was not prevented by the antioxidants Trolox and N-acetyl-cysteine. Oligomycin, inhibitor of F0F1-ATPase, prevented hypoxia-induced HIF-1α protein accumulation and had no effect on HIF-1α induction by hypoxia-mimicking agents desferrioxamine or dimethyloxalylglycine. The inhibitory effect of mitochondrial respiratory chain inhibitors and oligomycin on hypoxic HIF-1α content was pronounced in cells exposed to hypoxia (1.5% O2) but decreased markedly when cells were exposed to severe oxygen deprivation (anoxia). Taken together, these results do not support the role for mitochondrial reactive oxygen species in HIF-1α regulation, but rather suggest that inhibition of electron transport chain and impaired oxygen consumption affect HIF-1α accumulation in hypoxic cells indirectly via effects on prolyl hydroxylase function.
The end of “naïve reductionism”: rise of systems biology or renaissance of physiology?
Authors: Strange Kevin
Published: April 2005

Systems biology is an emerging discipline focused on tackling the enormous intellectual and technical challenges associated with translating genome sequence into a comprehensive understanding of how organisms are built and run. Physiology and systems biology share the goal of understanding the integrated function of complex, multicomponent biological systems ranging from interacting proteins that carry out specific tasks to whole organisms. Despite this common ground, physiology as an academic discipline runs the real risk of fading into the background and being superseded organizationally and administratively by systems biology. My goal in this article is to discuss briefly the cornerstones of modern systems biology, specifically functional genomics, nonmammalian model organisms and computational biology, and to emphasize the need to embrace them as essential components of 21st-century physiology departments and research and teaching programs.
Hepatocyte growth factor prevents tissue fibrosis, remodeling, and dysfunction in cardiomyopathic hamster hearts
Authors: Nakamura Teruya , Matsumoto Kunio , Mizuno Shinya , Sawa Yoshiki , Matsuda Hikaru , Nakamura Toshikazu
Published: April 2005

Structural remodeling of the myocardium, including myocyte hypertrophy, myocardial fibrosis, and dilatation, drives functional impairment in various forms of acquired and hereditary cardiomyopathy. Using cardiomyopathic Syrian hamsters with a genetic defect in δ-sarcoglycan, we investigated the potential involvement of hepatocyte growth factor (HGF) in the pathophysiology and therapeutics related to dilated cardiomyopathy, because HGF has previously been shown to be cytoprotective and to have benefits in acute heart injury. Late-stage TO-2 cardiomyopathic hamsters showed severe cardiac dysfunction and fibrosis, accompanied by increases in myocardial expression of transforming growth factor-β1 (TGF-β1), a growth factor responsible for tissue fibrosis. Conversely, HGF was downregulated in late-stage myopathic hearts. Treatment with recombinant human HGF for 3 wk suppressed cardiac fibrosis, accompanied by a decreased expression of TGF-β1 and type I collagen. Suppression of TGF-β1 and type I collagen by HGF was also shown in cultured cardiac myofibroblasts. Likewise, HGF suppressed myocardial hypertrophy, apoptosis in cardiomyocytes, and expression of atrial natriuretic polypeptide, a molecular marker of hypertrophy. Importantly, downregulation of the fibrogenic and hypertrophic genes by HGF treatment was associated with improved cardiac function. Thus the decrease in endogenous HGF levels may participate in the susceptibility of cardiac tissue to hypertrophy and fibrosis, and exogenous HGF led to therapeutic benefits in case of dilated cardiomyopathy in this model, even at the late-stage treatment.
Rewriting a Dramatic Old Testament Story the Story of Jephthah and his Daughter in Some Examples of Christian Devotional Literature
Authors: Houtman Cornelis
Published: April 2005

Four examples of the literary rewriting of Judg. 11:29-40 in devotional literature, dating from the end of the 18th century to the beginning of the 20th century, are described and analysed. All do away with the simplicity and "neutrality" found in the biblical story of Jephthah and his daughter and turn it into high drama with sharply drawn and distinct protagonists and a sometimes exuberant depiction of atmosphere. In the hands of the authors the story becomes the bearer of the theological ideas and moral views which the novelists and poets and their times espoused.
The Provisions on Gift in the Civil Code of the Russian Federation
Authors: Smith Stephen
Published: April 2005

The author offers a critical examination of the provisions on gift in the Civil Code of the Russian Federation. Focusing narrowly on the text of the code, the paper starts with a broad overview of, and commentary on, the provisions and then provides a detailed article-by-article commentary on individual provisions. Potential difficulties are identified (especially with respect to the notion of transfer, the repetition of articles, and the code's development of the concept of fiducia) and suggestions are offered for how the text might be clarified or, in certain cases, substantively changed. The author observes that the legal framework provided by the Russian code to regulate gift is a fundamentally sound one that broadly echoes the approach taken in other civil law jurisdictions.
Objects of Private Property in the Civil Code of the Russian Federation and in the Civil Code of Quebec
Authors: Lametti David
Published: April 2005

Property norms, in expressing a relationship among people through resources, must address in some manner the organization of property rights and the classification of objects of property. Both the Civil Code of the Russian Federation and the Civil Code of Quebec express some notion of the idea of what the author has called property-as-object, taking the form of certain distinctions: movable/immovable, corporeal/incorporeal, capital/revenue, or in commerce/out of commerce.The Russian code contains a rich discussion of the objects of property, with a larger, more explicit formal role for objects in the understanding of property rights as compared to the Quebec code. The articles on objects in general manifest the traditional civilist distinctions, while set in the context of present Russian society.Moreover, notwithstanding some initial lack of clarity in the Russian code's classifi cation between the objects of property and the subject-matter of other patrimonial rights, the objects of property are clearly distinguishable as a category and are important to understanding property relations. Despite the focus in the Russian code on "things" as the objects of property as opposed to "rights in things", it is nevertheless the case that the latter are an important part of the property relationship, and cannot be disentangled from "things".
Análisis del discurso con desempleados de larga duración durante entrevistas de inserción laboral
Authors: Cuadrado Isabel , Ramos Jose-Luis , Fernández Inmaculada
Published: April 2005

Este trabajo se centra en analizar cuáles son las estrategias discursivas y recursos semióticos que técnicos de las oficinas públicas de empleo y desempleados utilizan durante las entrevistas, en qué momento y con qué fin recurren a ellas y qué efectos provocan en la dinámica interactiva. La muestra está formada por dos técnicos del Servicio Público de Empleo Extremeño (SEXPE) y 18 desempleados de alto riesgo de exclusión social: analfabetos funcionales, inmigrantes y sujetos con problemas de salud mental. Se propone un proceso de formación en habilidades comunicativas centrado en la concienciación de sus propios comportamientos. Se realiza el análisis a través de la videograbación, entrevista y cuestionario, ajustándose el proceso a tres fases prediseñadas. Los resultados indican que el conocimiento y formación en mecanismos comunicacionales, verbales y no-verbales, favorecen la adaptación de los técnicos a las características personales de sus interlocutores y la disminución de control que ejercían sobre la entrevista.
Juicios de justicia distributiva y su relación con el sistema de valores humanos
Authors: Goikoetxea Edurne
Published: April 2005

Se examinan los juicios de justicia distributiva, las relaciones entre estos juicios y el sistema de valorres terminales de Rokeach (1973) y los cambios en el sistema de valores que ocurren cuando se realiza una tarea de justicia. Participaron 828 universitarios completando la Escala de Valores de Rokeach y la tarea de la Historia de las Manzanas (Keats y Fu-Xi, 1994). Los resultados mostraron que el patrón de distribución más frecuente fue el igualitario, seguido del equitativo. Un análisis predictivo discriminante indicó que sólo el 48% de los participantes del grupo igualitario y el 68% del grupo equitativo fueron correctamente identificados en base a sus puntuaciones en la jerarquía de valores. Aunque los valores predijeron débilmente los juicios de justicia, la ordenación de valores se ajusta al modelo del pluralismo de valores de Tetlock, Peterson y Lerner (1996). Los dos grupos argumentaron de modo muy similar cuando justificaron sus patrones de distribución en términos de valores
Egr-1 abrogates the block imparted by c-Myc on terminal M1 myeloid differentiation
Authors: Shafarenko Marianna , Liebermann Dan A. , Hoffman Barbara
Published: April 2005

Both deregulated growth and blocks in differentiation cooperate in the multistage process of leukemogenesis. Thus, understanding functional interactions between genes that regulate normal blood cell development, including cell growth and differentiation, and how their altered expression contributes to leukemia, is important for rational drug design. Previously, we have shown that the zinc finger transcription factor Egr-1 plays a role in monocytic differentiation. Ectopic expression of Egr-1 in M1 myeloblastic leukemia cells was observed to activate the macrophage differentiation program in the absence of the differentiation inducer interleukin 6 (IL-6) and to promote terminal differentiation in its presence. In addition, we have shown that deregulated expression of the proto-oncogene c-myc blocks the myeloid terminal differentiation program. Here we show that restoring expression of Egr-1 in M1 cells that express deregulated c-Myc abrogates the c-Myc block in terminal differentiation, resulting in cells that undergo functional macrophage maturation. However, there is an absence of both growth arrest and cell adhesion. In addition, Egr-1 expression diminished M1myc leukemogenicity in vivo. These findings indicate that Egr-1 can act as a tumor suppressor gene and suggest that Egr-1 or Egr-1 targets may provide important tools for differentiation therapy in certain leukemic phenotypes.
Psychiatric outpatient consultation for seniors. Perspectives of family physicians, consultants, and patients / family: A descriptive study
Authors: Yaffe Mark J , Primeau Francois , McCusker Jane , Cole Martin G , Belzile Eric , Dendukuri Nandini , Elie Michel , Laplante Johanne
Published: April 2005

Background

Family practitioners take care of large numbers of seniors with increasingly complex mental health problems. Varying levels of input may be necessary from psychiatric consultants. This study examines patients'/family, family practitioners', and psychiatrists' perceptions of the bi-directional pathway between such primary care doctors and consultants.

Methods

An 18 month survey was conducted in an out-patient psychogeriatric clinic of a Montreal university-affiliated community hospital. Cognitively intact seniors referred by family practitioners for assessment completed a satisfaction and expectation survey following their visits with the psychiatric consultants. The latter completed a self-administered process of care questionnaire at the end of the visit, while family doctors responded to a similar survey by telephone after the consultants' reports had been received. Responses of the 3 groups were compared.

Results

101 seniors, referred from 63 family practitioners, met the study entry criteria for assessment by 1 of 3 psychogeriatricians. Both psychiatrists and family doctors agreed that help with management was the most common reason for referral. Family physicians were accepting of care of elderly with mental health problems, but preferred that the psychiatrists assume the initial treatment; the consultants preferred direct return of the patient; and almost 1/2 of patients did not know what to expect from the consultation visit. The rates of discordance in expectations were high when each unique patient-family doctor-psychiatrist triad was examined.

Conclusion

Gaps in expectations exist amongst family doctors, psychiatrists, and patients/family in the shared mental health care of seniors. Goals and anticipated outcomes of psychogeriatric consultation require better definition.
Potential cellular receptors involved in hepatitis C virus entry into cells
Authors: Favre Daniel , Muellhaupt Beat
Published: April 2005

Hepatitis C virus (HCV) infects hepatocytes and leads to permanent, severe liver damage. Since the genomic sequence of HCV was determined, progress has been made towards understanding the functions of the HCV-encoded proteins and identifying the cellular receptor(s) responsible for adsorption and penetration of the virus particle into the target cells. Several cellular receptors for HCV have been proposed, all of which are associated with lipid and lipoprotein metabolism. This article reviews the cellular receptors for HCV and suggests a general model for HCV entry into cells, in which lipoproteins play a crucial role.
Feasibility of chemosensitivity testing in soft tissue sarcomas
Authors: Lehnhardt Marcus , Muehlberger Thomas , Kuhnen Cornelius , Brett Daniel , Steinau Hans U , Jafari Hamid Joneidi , Steinstraesser Lars , Müller Oliver , Homann Heinz H
Published: April 2005

Background

Soft tissue sarcomas comprise less than 1% of all solid malignancies. The presentation and behavior of these tumors differs depending on location and histological characteristics. Standard therapy consists of complete surgical resection in combination with adjuvant radiotherapy. The role of chemotherapy is not clearly defined and is largely restricted to clinical trials. Only a limited number of agents have proved to be effective in soft tissue sarcomas. The use of doxorubicin, epirubicin and ifosfamide allowed response rates of more than 20%. In addition, recent chemotherapy trials did not demonstrate any significant differences in efficacy for various histological subtypes.

Methods

The objective of this study was to gain additional information about the chemosensitivity of soft tissue sarcomas to seven 7 different chemotherapy agents as single drugs and 4 combinations. Therefore we used an established ATP based in-vitro testing system and examined 50 soft tissue sarcomas. Chemosensitivity was assessed using a luciferin-luciferase-based luminescence assay providing individual chemosensitivity indices for each agent tested.

Results

The sensitivity varied widely according to the histological subtypes. The tumors state of cellular dedifferentiation played a crucial role for the efficiency of the chemotherapeutic agents. The sensitivity also depended on the presentation of the sarcoma as a primary or recurrent tumor. The highest sensitivity was demonstrated for actinomycin D as a single agent, with 74% of the tumor samples exhibiting a high-grade sensitivity (20% low sensitivity, no resistance). The combination of actinomycin D and ifosfamide yielded a high sensitivity in 76% (2% resistance). Doxorubicin as a mono-therapy or in combination with ifosfamide achieved high sensitivity in 70% and 72%, respectively, and resistance in 6% of the samples.

Conclusion

Chemosensitivity testing is feasible in soft tissue sarcomas. It can be used to create sensitivity and resistance profiles of established and new cytotoxic agents and their combinations in soft tissue sarcomas. Our data demonstrate measurable discrepancies of the drug efficiency in soft tissue sarcomas, sarcoma subtypes and tumor recurrencies. However, current therapeutic regime does not take this in consideration, yet.
A comparison of polarized and non-polarized human endometrial monolayer culture systems on murine embryo development
Authors: Baghaban Eslami Nejad Mohamad Reza , Rezazadeh Valojerdi Mojtaba , Kazemi Ashtiani Saeed
Published: April 2005

Background

Co-culture of embryos with various somatic cells has been suggested as a promising approach to improve embryo development. Despite numerous reports regarding the beneficial effects of epithelial cells from the female genital tract on embryo development in a co-culture system, little is known about the effect of these cells when being cultured under a polarized condition on embryo growth. Our study evaluated the effects of in vitro polarized cells on pre-embryo development.

Methods

Human endometrial tissue was obtained from uterine specimens excised at total hysterectomy performed for benign indications. Epithelial cells were promptly isolated and cultured either on extra-cellular matrix gel (ECM-Gel) coated millipore filter inserts (polarized) or plastic surfaces (non-polarized). The epithelial nature of the cells cultured on plastic was confirmed through immunohistochemistry, and polarization of cells cultured on ECM-Gel was evaluated by transmission electron microscopy (TEM). One or two-cell stage embryos of a superovulated NMRI mouse were then flushed and placed in culture with either polarized or non-polarized cells and medium alone. Development rates were determined for all embryos daily and statistically compared. At the end of the cultivation period, trophectoderm (TE) and inner cell mass (ICM) of expanded blastocysts from each group were examined microscopically.

Results

Endometrial epithelial cells cultured on ECM-Gel had a highly polarized columnar shape as opposed to the flattened shape of the cells cultured on a plastic surface. The two-cell embryos cultured on a polarized monolayer had a higher developmental rate than those from the non-polarized cells. There was no statistically significant difference; still, the blastocysts from the polarized monolayer, in comparison with the non-polarized group, had a significantly higher mean cell number. The development of one-cell embryos in the polarized and non-polarized groups showed no statistically significant difference.

Conclusion

Polarized cells could improve in vitro embryo development from the two-cell stage more in terms of quality (increasing blastocyst cellularity) than in terms of developmental rate.
7200 years of Rhône river flooding activity in Lake Le Bourget, France: a high-resolution sediment record of NW Alps hydrology
Authors: Arnaud F. , Revel M. , Chapron E. , Desmet M. , Tribovillard N.
Published: April 2005

Magnetic susceptibility (MS) was measured with high resolution (5 mm) on a 9 m long, 14C dated core from Lake Le Bourget (Savoie, France), spanning the last 7200 years. The strong correlation (R=0.85) of the MS with the silicate-borne suite of elements (Si, Al, Fe, Mg, K) and anti-correlation with the carbonate content (R =-0.87) allows it to be used as a proxy for the fluctuations of the abundance of riverborne clastic fraction versus authigenic carbonates in sediment. As the Rhône is the only river bringing a significant amount of silicate minerals to the coring site, the MS downstream is interpreted as a proxy of the Rhône suspended load discharge in Lake Le Bourget. This is confirmed over the last 3000 years by the good match with the evolution of hydrological activity of the Rhône as it is known through geomorphological studies of well-dated archaeological sites. Over the last 7200 years, the record is consistent with the regional record of lake water-level fluctuations. While the intensity of the MS signal might be widely affected by the human impact on soil stability, the timing of the period of enhanced hydrological activity appears to be mostly climate-related, and should thus constitute a first step toward a high-resolution (< 8 yr) continuous history of hydrological conditions in the NW Alps.
Unusual mid-Holocene abundance of Ulmus in western Ireland-human impact in the absence of a pathogen?
Authors: Lamb Henry , Thompson Adrian
Published: April 2005

A Holocene pollen record from Co. Clare, western Ireland, shows unusually high Ulmus pollen frequencies until about 2500 cal. BP, interrupted by four brief episodes of reduced Ulmus pollen between 6000 and 3000 cal. BR Localized anthropogenic disturbance of the vegetation during this interval is inferred from higher magnetic susceptibility of the sediments, indicating soil erosion, and from increased Poaceae and Plantago pollen. The continued abundance of elm at several sites in Ireland, despite human impact, suggests that disease was a less significant factor in the reduction of Irish elm populations than elsewhere in northwestern Europe. It may be that the pathogen, its dispersal agent, or susceptible elm ecotypes were locally absent near the western range margin of elm, reinforcing the argument that the combined effects of human exploitation and a pathogen were necessary to cause the permanent elm decline at 6000 cal. BP in most of northwestern Europe.
Palaeosols in Saharan and Sahelian dunes of Chad: archives of Holocene North African climate changes
Authors: Mauz B. , Felix-Henningsen P.
Published: April 2005

Limnic sediments and palaeosols are frequently present in dunes of the Sahara and Sahel deserts of Chad. This study focused on genesis and degree of development of the palaeosols and the timing of soil formation. The soils are Cambic Arenosols formed by precipitation-induced silicate weathering and leaching. The upper parts of the Cambic Arenosols are indurated due to accumulation of salt and amorphous silica during a drier climate following soil formation. The optical age data reveal the occurrence of one or two distinct short-lived humid climate intervals shortly after-5 ka and before-2.5 ka and the formation of local desert lakes shortly after -5 ka. The study further suggests that rapid climate changes occurred mainly in the mid-Holocene whereas the early-Holocene humid period lasted longer.
Holocene climate variability and periodicities in south-central Sweden, as interpreted from peat humification analysis
Authors: Borgmark Anders
Published: April 2005

Analysis of the decomposition of peat has been used to identify climatic shifts over the last 10 000 years in two raised bogs, Stomyren and Kortlandamossen, south-central Sweden. Age-depth curves have been constructed using radiocarbon dates and tephra layers. Peat humification data have been subjected to spectral analyses using the Lomb-Scargle Fourier method and reveal a periodicity of c. 250 years in both records. Cycles of c. 200 yr and c. 400 yr were found at Stomyren and at Kortlandamossen, respectively. These periodicities could correspond to changes in solar activity levels. A test estimating the possible level of noise has been applied to the spectral analyses. The humification indices indicate prominent shifts to wetter conditions at c. 7500, 4300-4200, 3700-3500 and 2800-2400 cal. yr BP. The most distinct drier phases start at c. 4500 and 3250 cal. yr BP.
Estimates of‘relative pollen productivity’ and‘relevant source area of pollen’ for major tree taxa in two Norfolk (UK) woodlands
Authors: Bunting M. Jane , Armitage Richard , Binney Heather A. , Waller Martyn
Published: April 2005

Surface sample pollen assemblages and vegetation data collected from two East Anglian fen carr sites with adjacent dry woodland belts are analysed to estimate the relevant source area of pollen (RSAP) and the relative pollen productivity (RPP) values for the major canopy trees. The‘relevant source area of pollen’ is found to be on the order of 50-150 m, comparable with but slightly greater than estimates for forest hollow contexts in dry woodlands. Estimates of pollen productivity relative to Quercus are then compared with published values from south Sweden. Betula and Corylus values are similar, but some values estimated for taxa characteristic of wetter habitats, and therefore competitively advantaged in the fen carr system (Alnus, Salix and Fraxinus), are substantially higher at one or both sites. The results suggest that palaeoecological records from fen carr systems should be interpreted as reflecting predominantly local vegetation signals once the tree canopy is established.
In-vitro and in-vivo anti-inflammatory and antinociceptive effects of the methanol extract of the roots of Morinda officinalis
Authors: Kim In-Tae , Park Hee-Juhn , Nam Jung-Hwan , Park Young-Mi , Won Jong-Heon , Choi Jongwon , Choe Bong-Keun , Lee Kyung-Tae
Published: April 2005

The anti-inflammatory effects of the methanol extract of the roots of Morinda officinalis (MEMO) (Rubiaceae) were evaluated in-vitro and in-vivo. The effects of MEMO on lipopolysaccharide (LPS)-induced responses in the murine macrophage cell line RAW 264.7 were examined. MEMO potently inhibited the production of nitric oxide (NO), prostaglandin E2 and tumour necrosis factor-α (TNF-α) in LPS-stimulated RAW 264.7 macrophages. Consistent with these results, the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) at the protein level, and of iNOS, COX-2 and TNF-α at the mRNA level, was also inhibited by MEMO in a concentration-dependent manner. Furthermore, MEMO inhibited the nuclear factor kappa B (NF-κB) activation induced by LPS, and this was associated with the prevention of degradation of the inhibitor κB (IκB), and subsequently with attenuated p65 protein in the nucleus. The anti-inflammatory effect of MEMO was examined in rats using the carrageenan-induced oedema model. The antinociceptive effects of MEMO were assessed in mice using the acetic acid-induced abdominal constriction test and the hot-plate test. MEMO (100, 200 mg kg−1 per day, p.o.) exhibited anti-inflammatory and antinociceptive effects in these animal models. Taken together, the data demonstrate that MEMO has anti-inflammatory and antinociceptive activity, inhibiting iNOS, COX-2 and TNF-α expression by down-regulating NF-κB binding activity.
The lipid composition of autophagic vacuoles regulates expression of multilamellar bodies
Authors: Lajoie Patrick , Guay Ginette , Dennis James W. , Nabi Ivan R.
Published: April 2005

Multilamellar bodies (MLBs) are responsible for surfactant secretion in type II alveolar cells but also accumulate in other cell types under pathological conditions, including cancer and lysosomal storage diseases such as Niemann-Pick C (NPC), a congenital disease where defective cholesterol transport leads to its accumulation in lysosomes. Mv1Lu type II alveolar cells transfected with Golgi β1,6 N-acetylglucosaminyltransferase V (Mgat5), enhancing the polylactosamine content of complex-type N-glycans, exhibit stable expression of MLBs whose formation requires lysosomal proteolysis within dense autophagic vacuoles. MLBs of Mgat5-transfected Mv1Lu cells are rich in phospholipids and have low levels of cholesterol. In Mv1Lu cells treated with the NPC-mimicking drug U18666A, cholesterol-rich MLBs accumulate independently of both Mgat5 expression and lysosomal proteolysis. Inhibition of autophagy by blocking the PI 3-kinase pathway with 3-methyladenine prevents MLB formation and results in the accumulation of non-lamellar, acidic lysosomal vacuoles. Treatment with 3-methyladenine inhibited the accumulation of monodansylcadaverine, a phospholipid-specific marker for autophagic vacuoles, but did not block endocytic access to the lysosomal vacuoles. Induction of autophagy via serum starvation resulted in an increased size of cholesterol-rich MLBs. Although expression of MLBs in the Mv1Lu cell line can be induced by modulating lysosomal cholesterol or protein glycosylation, an autophagic contribution of phospholipids is critical for the formation of concentric membrane lamellae within late lysosomal organelles.
Robust maneuvering control design of an aircraft via dynamic inversion and μ-synthesis
Authors: Moghaddam M M , Moosavi S F
Published: April 2005

In this research, a robust controller for a nonlinear model of an aircraft with unmodelled dynamic uncertainty is designed. The closed-loop system (aircraft) should remain stable and perform manoeuvring acceptably. By using the ‘Dynamic Inversion Method’ the nonlinear responses are transformed into linear ones. Then, using the μ-analysis and synthesis technique a robustly performed controller is designed against uncertainties and control-surface limitations. Next, the actual response of the aircraft is computed using simulation. Finally, the order of the controller is reduced and the same analysis is repeated for the reduced order controller. It shows that the controller performs robustly and stably.
Finite element analysis of shafts under combined loads
Authors: Robotham W S , Hong Y S , Hyde T H , Williams E J
Published: April 2005

The trend for aeroengines with increasing thrust capacities requires the development of shaft technology to deal with this greater power transmission, while still restricting their dimensions and weight. Thin-walled designs can assist in achieving this objective, but are limited by their torsional collapse behaviour. By improving the understanding of the torsional buckling behaviour of shafts, this will enable improved shaft designs able to deal with the increase load capacities required. Until recently the prediction of buckling failures of such thin-walled shafts was by empirical and theoretical equations, which are, in general, unnecessarily conservative. A previous publication described the development and validation of an accurate and versatile finite element-based analysis technique for predicting the torsional buckling behaviour of thin-walled shafts. Although for a typical aeroengine drive shaft the dominant loading mode, under normal conditions, is torsion, aeroengine drive shafts will also experience bending and axial loading. The aim of this paper is to prove that the previously developed finite element buckling methodology can be used for buckling analyses of shafts under combined load situations. This paper presents validation cases for which experimental test results are compared with the results of finite element analyses, under various loading modes; it shows that the behaviour of shafts under combined loads can be accurately predicted using the finite element method.
A flutter suppression active controller
Authors: De Marqui C , Belo E M , Marques F D
Published: April 2005

Flutter is a dynamic aeroelastic instability that involves the interaction of aerodynamic, elastic, and inertial forces. This instability may occur in aircraft surfaces, like wings and tails, leading them to a divergent oscillatory motion. A classical two-degrees-of-freedom flutter is an interaction of bending and torsional modes of vibration of a structure. A flexible mount system has been developed for flutter tests with rigid wings in wind tunnels. This flexible mount has to provide a well-defined two-degrees-of-freedom system on which rigid wings encounter flutter. Active control schemes for flutter suppression can be tested using this experimental set-up. An aeroelastic model is formulated to simulate the aeroelastic behaviour of this system. The equations of motion are developed using Lagrange' equations and the Principle of Virtual Work, resulting in a state space representation. This is a convenient way to determine pitch and plunge time responses for several initial conditions and velocities. Using this model, a state feedback controller of the form u = – Kx is determined. The wind tunnel model is a rectangular wing with a NACA 0012 airfoil section and a trailing edge control surface as actuator. The main goal is to suppress flutter and to maintain the stability of the closed loop system.
An application of the mechanical rotation scheme to an analysis of the motion of flying objects
Authors: Grevtsov N , Melts I , Sazonov D , Wagstaff P
Published: April 2005

A method of analysis of the motion of a flying object based on the rotation scheme of a rigid body is considered. This method permits both the attitude and the trajectory of the centre of gravity to be calculated. The latter is related to the fact (which is well known in differential geometry) that local behaviour of any three-dimensional curve is completely determined by its curvature and twisting. The singularities inherent in the equations of motion with the use of Euler angles are absent in the presented method. Some analytical examples are included into this paper for clarity.
Digital imaging in pathology: the case for standardization
Authors: Yagi Yukako , Gilbertson John R
Published: April 2005

The process of digital imaging in microscopy is a series of operations, each contributing to the quality of the final image that is displayed on the computer monitor. The operations include sample preparation and staining by histology, optical image formation by the microscope, digital image sampling by the camera sensor, postprocessing and compression, transmission across the network and display on the monitor. There is an extensive literature about digital imaging and each step of the process is fairly well understood. However, the complete process is very hard to standardize or even to understand fully. The important concepts for pathology imaging standards are: (1) systems should be able to share image files, (2) the standards should allow the transmission of information on baseline colours and recommended display parameters, (3) the images should be useful to the pathologist, not necessarily better or worse than direct examination of a slide under the microscope, (4) a mechanism to evaluate image quality objectively should be present, (5) a mechanism to adjust and correct the minor errors of tissue processing should be developed, (6) a public organization should support pathologists in the development of standards.
Education through telemedicine networks: setting quality standards
Authors: Shershneva Marianna B , Olson Curtis A
Published: April 2005

Quality standards for educational programming have received limited attention in telemedicine. We selected five sets of standards from the distance education literature established by: (1) the American Council on Education; (2) the American Distance Education Consortium; (3) the Council of Regional Accrediting Commissions; (4) the Distance Education and Training Council; (5) the Innovations in Distance Education Project. The standards were reviewed to determine the purposes they were intended to serve and the process by which they were established. The content of the five sets of standards were summarized around the 'four commonplaces' of education: learner, teacher, curriculum and context. Four major findings emerged. First, none of the sets of standards addresses all of the issues that are potentially relevant to telemedicine education; all emphasize certain topics while neglecting others. Second, there are some important aspects of telemedicine that are not addressed at all, such as patient confidentiality. Third, the standards generally provide a framework for defining high quality in distance education, leaving to those at the local level the task of deciding how a standard applies in their setting. Finally, the standards reviewed have many elements that could potentially apply to telemedicine education. Setting quality standards for education through telemedicine requires a systematic approach and a means for continuous improvement of those standards.
Prp8 protein: At the heart of the spliceosome
Authors: GRAINGER RICHARD J. , BEGGS JEAN D.
Published: April 2005

Pre-messenger RNA (pre-mRNA) splicing is a central step in gene expression. Lying between transcription and protein synthesis, pre-mRNA splicing removes sequences (introns) that would otherwise disrupt the coding potential of intron-containing transcripts. This process takes place in the nucleus, catalyzed by a large RNA–protein complex called the spliceosome. Prp8p, one of the largest and most highly conserved of nuclear proteins, occupies a central position in the catalytic core of the spliceosome, and has been implicated in several crucial molecular rearrangements that occur there. Recently, Prp8p has also come under the spotlight for its role in the inherited human disease, Retinitis Pigmentosa.

Prp8 is unique, having no obvious homology to other proteins; however, using bioinformatical analysis we reveal the presence of a conserved RNA recognition motif (RRM), an MPN/JAB domain and a putative nuclear localization signal (NLS). Here, we review biochemical and genetical data, mostly related to the human and yeast proteins, that describe Prp8’s central role within the spliceosome and its molecular interactions during spliceosome formation, as splicing proceeds, and in post-splicing complexes.
A genome-wide analysis of C/D and H/ACA-like small nucleolar RNAs in Trypanosoma brucei reveals a trypanosome-specific pattern of rRNA modification
Authors: LIANG XUE-HAI , ULIEL SHAI , HURY AVRAHAM , BARTH SARIT , DONIGER TIRZA , UNGER RON , MICHAELI SHULAMIT
Published: April 2005

Small nucleolar RNAs (snoRNAs) constitute newly discovered noncoding small RNAs, most of which function in guiding modifications such as 2′-O-ribose methylation and pseudouridylation on rRNAs and snRNAs. To investigate the genome organization of Trypanosoma brucei snoRNAs and the pattern of rRNA modifications, we used a whole-genome approach to identify the repertoire of these guide RNAs. Twenty-one clusters encoding for 57 C/D snoRNAs and 34 H/ACA-like RNAs, which have the potential to direct 84 methylations and 32 pseudouridines, respectively, were identified. The number of 2′-O-methyls (Nms) identified on rRNA represent 80% of the expected modifications. The modifications guided by these RNAs suggest that trypanosomes contain many modifications and guide RNAs relative to their genome size. Interestingly, ~40% of the Nms are species-specific modifications that do not exist in yeast, humans, or plants, and 40% of the species-specific predicted modifications are located in unique positions outside the highly conserved domains. Although most of the guide RNAs were found in reiterated clusters, a few single-copy genes were identified. The large repertoire of modifications and guide RNAs in trypanosomes suggests that these modifications possibly play a central role in these parasites.
Seawi—a sea urchin piwi/argonaute family member is a component of MT-RNP complexes
Authors: RODRIGUEZ ALEXIS J. , SEIPEL SUSAN A. , HAMILL DANIELLE R. , ROMANCINO DANIELE P. , DI CARLO MARTA , SUPRENANT KATHY A. , BONDER EDWARD M.
Published: April 2005

The piwi/argonaute family of proteins is involved in key developmental processes such as stem cell maintenance and axis specification through molecular mechanisms that may involve RNA silencing. Here we report on the cloning and characterization of the sea urchin piwi/argonaute family member seawi. Seawi is a major component of microtubule-ribonucleoprotein (MT-RNP) complexes isolated from two different species of sea urchin, Strongylocentrotus purpuratus and Paracentrotus lividus. Seawi co-isolates with purified ribosomes, cosediments with 80S ribosomes in sucrose density gradients, and binds microtubules. Seawi possesses the RNA binding motif common to piwi family members and binds P. lividus bep4 mRNA, a transcript that co-isolates with MT-RNP complexes and whose translation product has been shown to play a role in patterning the animal–vegetal axis. Indirect immunofluorescence studies localized seawi to the cortex of unfertilized eggs within granule-like particles, the mitotic spindle during cell division, and the small micromeres where its levels were enriched during the early cleavage stage. Lastly, we discuss how seawi, as a piwi/argonaute family member, may play a fundamentally important role in sea urchin animal–vegetal axis formation and stem cell maintenance.
Editing efficiency of a Drosophila gene correlates with a distant splice site selection
Authors: AGRAWAL RITESH , STORMO GARY D.
Published: April 2005

RNA editing and alternative splicing are two processes that increase protein diversity. The relationship between the two processes is not well understood. There are a few examples of correlations between editing and alternative splicing, but these are all nearby effects. A search for alternative splicing among 16 edited genes in Drosophila reveals two novel instances of alternative splicing. In one example where alternative splicing occurs downstream of editing, a strong correlation between editing efficiency and splice site selection is observed. In contrast, when editing occurs downstream of alternative splicing, no correlation is seen. These results suggest some models for the coupling of editing and splicing processes.
Image-making and the circulation of images: Peale, Trumbull and the founding fathers
Authors: Homberger Eric
Published: April 2005

Images of the founding fathers shaped the way Americans saw their nation and its leading figures. Justly celebrated portraits by Charles Willson Peale, John Trumbull and others, claimed the authority of factual accuracy. Such images were part of the late eighteenth-century world of
image-making which spread across Europe and the United States. The financial interests of the painters and engravers, and the changeable market for their images, meant that images were frequently copied from other images, from statue to portrait painting to mezzotint engraving. The experience
of the painters (Peale was a radical patriot, Trumbull was a conservative Federalist) influenced the market for their work, but both men regarded their heroic portraits as ‘a means of exciting an Emulation in our Posterity’. John Adams in his Discourses of Davila in 1790
articulated the central role for admiration or emulation in the strengthening of the patriotic impulse. Later social theorists, such as Thorstein Veblen and Charles Horton Cooley, argued that emulation was more important in consumption and the appetite for wealth, than in the transmission
of high ideals. The failure of many proposals to create memorials to the founding fathers in New York City, from 1825 to 1850, suggests that the model of emulation endorsed by Adams needs to be reconsidered. New Yorkers were not indifferent to patriotic heroes, as Walt Whitman feared; but
the conservative and hierarchical dimensions of emulation aroused scepticism. The origin of so many proposals for civic monuments came from the city's elite. But the public was growing reluctant to accept their leadership in public life.
University research management: towards a global profession?
Authors: Kirkland John
Published: April 2005

The management of research is a critical topic for universities worldwide. It is also one in which we all have much to learn. For developing countries, however, the need is perhaps even greater. Without effective research management, their task of becoming equal players in the global
knowledge market will become even harder. It is in all of our interests that they succeed.
The Impact of Hearing Protection on Sound Localization and Orienting Behavior
Authors: Simpson Brian D. , Bolia Robert S. , McKinley Richard L. , Brungart Douglas S.
Published: April 2005

The effect of hearing protection devices (HPDs) on sound localization was examined in the context of an auditory-cued visual search task. Participants were required to locate and identify a visual target in a field of 5, 20, or 50 visual distractors randomly distributed on the interior surface of a sphere. Four HPD conditions were examined: earplugs, earmuffs, both earplugs and earmuffs simultaneously (double hearing protection), and no hearing protection. In addition, there was a control condition in which no auditory cue was provided. A repeated measures analysis of variance revealed significant main effects of HPD for both search time and head motion data (p < .05), indicating that the degree to which localization is disrupted by HPDs varies with the type of device worn. When both earplugs and earmuffs are worn simultaneously, search times and head motion are more similar to those found when no auditory cue is provided than when either earplugs or earmuffs alone are worn, suggesting that sound localization cues are so severely disrupted by double hearing protection the listener can recover little or no information regarding the direction of sound source origin. Potential applications of this research include high-noise military, aerospace, and industrial settings in which HPDs are necessary but wearing double protection may compromise safety and/or performance.
Youth Suicide Prevention: A Survey of Public School Superintendents' Acceptability of School‐Based Programs
Authors: Scherff Andrew R. , Eckert Tanya L. , Miller David N.
Published: April 2005

From a random sample of members of the 2000–2001 membership directory of the American Association of School Administrators (AASA), public school administrators' acceptability ratings of three school‐based programs for the prevention of adolescent suicide were examined. A total of 210 (46%) respondents examined a description of a suicide prevention program and completed a measure designed to evaluate the acceptability of suicide prevention programs. Three suicide prevention programs were evaluated for their acceptability, and included: (a) school‐wide curriculum‐based programs presented to students; (b) in‐service presentations to school staff; and (c) self‐report screening programs for students. The results indicated that superintendents rated the staff in‐service training and curriculum‐based programs as significantly more acceptable than the school‐wide screening program. In addition, the school‐wide screening program was rated as significantly more intrusive by school psychologists than the staff in‐service training or curriculum‐based prevention programs. Limitations of the study and future research directions are discussed.