bluuebunny/crossref_metadata_2025 huggingface dataset:
Discrimination among potential buloke (Allocasuarina leuhmannii) feeding trees by the endangered south-eastern red-tailed black-cockatoo (Calyptorhynchus banksii graptogyne)
Authors: Maron Martine , Lill Alan
Published: June 2004

Remnant buloke (Allocasuarina luehmannii) woodland and scattered buloke trees appear to provide an important seasonal food resource for the endangered south-eastern red-tailed black-cockatoo (Calyptorhynchus banksii graptogyne). The factors that differed between buloke trees in which the cockatoos fed and those in which they did not feed were investigated in two consecutive years (Season 1 and Season 2). Tree diameter at breast height (DBH), individual mean seed dry mass, individual mean cone dry mass, mean number of seeds per cone, and proportion of total cone mass comprising seeds (seed ratio) were all significantly greater in feeding than non-feeding trees in both Season 1 and Season 2. A predictive model incorporating these five variables correctly classified 83% of trees measured in Season 1 as either feeding or non-feeding trees. Validation of predictive models with new data is essential in evaluating model performance, so the model was used to classify the feeding and non-feeding trees from which the variables were recorded during Season 2. The model, although derived only from the data collected during Season 1, was equally as effective in predicting the feeding status of trees in Season 2, despite the fact that the trees in which the cockatoos fed during the second year were not the same individual trees as those used in the previous year. The differences between feeding and non-feeding trees suggested that cockatoos choose to feed in trees in which they are able to optimise their foraging efficiency. As individual buloke trees appear to vary in their suitability for cockatoo foraging from year to year, it is not possible to exclude any buloke within the range of the cockatoo as a potential future food resource for this endangered bird.
A large-area, flexible pressure sensor matrix with organic field-effect transistors for artificial skin applications
Authors: Someya Takao , Sekitani Tsuyoshi , Iba Shingo , Kato Yusaku , Kawaguchi Hiroshi , Sakurai Takayasu
Published: June 2004

It is now widely accepted that skin sensitivity will be very important for future robots used by humans in daily life for housekeeping and entertainment purposes. Despite this fact, relatively little progress has been made in the field of pressure recognition compared to the areas of sight and voice recognition, mainly because good artificial “electronic skin” with a large area and mechanical flexibility is not yet available. The fabrication of a sensitive skin consisting of thousands of pressure sensors would require a flexible switching matrix that cannot be realized with present silicon-based electronics. Organic field-effect transistors can substitute for such conventional electronics because organic circuits are inherently flexible and potentially ultralow in cost even for a large area. Thus, integration of organic transistors and rubber pressure sensors, both of which can be produced by low-cost processing technology such as large-area printing technology, will provide an ideal solution to realize a practical artificial skin, whose feasibility has been demonstrated in this paper. Pressure images have been taken by flexible active matrix drivers with organic transistors whose mobility reaches as high as 1.4 cm
2
/V·s. The device is electrically functional even when it is wrapped around a cylindrical bar with a 2-mm radius.
Ca
2+
activates human homologous recombination protein Rad51 by modulating its ATPase activity
Authors: Bugreev Dmitry V. , Mazin Alexander V.
Published: June 2004

Human Rad51 (hRad51) protein plays a key role in homologous recombination and DNA repair. hRad51 protein forms a helical filament on single-stranded DNA (ssDNA), which performs the basic steps of homologous recombination: a search for homologous double-stranded DNA (dsDNA) and DNA strand exchange. hRad51 protein possesses DNA-dependent ATPase activity; however, the role of this activity has not been understood. Our current results show that Ca
2+
greatly stimulates DNA strand exchange activity of hRad51 protein. We found that Ca
2+
exerts its stimulatory effect by modulating the ATPase activity of hRad51 protein. Our data demonstrate that, in the presence of Mg
2+
, the hRad51-ATP-ssDNA filament is quickly converted to an inactive hRad51-ADP-ssDNA form, due to relatively rapid ATP hydrolysis and slow dissociation of ADP. Ca
2+
maintains the active hRad51-ATP-ssDNA filament by reducing the ATP hydrolysis rate. These findings demonstrate a crucial role of the ATPase activity in regulation of DNA strand exchange activity of hRad51 protein. This mechanism of Rad51 protein regulation by modulating its ATPase activity is evolutionarily recent; we found no such mechanism for yeast Rad51 (yRad51) protein.
Synthesis of the thapsigargins
Authors: Ley Steven V. , Antonello Alessandra , Balskus Emily P. , Booth David T. , Christensen Søren B. , Cleator Ed , Gold Helen , Högenauer Klemens , Hünger Udo , Myers Rebecca M. , Oliver Steven F. , Simic Oliver , Smith Martin D. , Søhoel Helmer , Woolford Alison J. A.
Published: June 2004

The thapsigargins are a family of complex guaianolides with potent and selective Ca
2+
-modulating properties. This article documents the evolution of a synthetic route through several iterations to a final practical and scaleable synthetic route capable of generating both unnatural and natural products based around the guaianolide skeleton.
Small molecules targeting severe acute respiratory syndrome human coronavirus
Authors: Wu Chung-Yi , Jan Jia-Tsrong , Ma Shiou-Hwa , Kuo Chih-Jung , Juan Hsueh-Fen , Cheng Yih-Shyun E. , Hsu Hsien-Hua , Huang Hsuan-Cheng , Wu Douglass , Brik Ashraf , Liang Fu-Sen , Liu Rai-Shung , Fang Jim-Min , Chen Shui-Tein , Liang Po-Huang , Wong Chi-Huey
Published: June 2004

Severe acute respiratory syndrome (SARS) is an infectious disease caused by a novel human coronavirus. Currently, no effective antiviral agents exist against this type of virus. A cell-based assay, with SARS virus and Vero E6 cells, was developed to screen existing drugs, natural products, and synthetic compounds to identify effective anti-SARS agents. Of >10,000 agents tested, ≈50 compounds were found active at 10 μM; among these compounds, two are existing drugs (Reserpine 13 and Aescin 5) and several are in clinical development. These 50 active compounds were tested again, and compounds 2–6, 10, and 13 showed active at 3 μM. The 50% inhibitory concentrations for the inhibition of viral replication (EC
50
) and host growth (CC
50
) were then measured and the selectivity index (SI = CC
50
/EC
50
) was determined. The EC
50
, based on ELISA, and SI for Reserpine, Aescim, and Valinomycin are 3.4 μM (SI = 7.3), 6.0 μM (SI = 2.5), and 0.85 μM (SI = 80), respectively. Additional studies were carried out to further understand the mode of action of some active compounds, including ELISA, Western blot analysis, immunofluorescence and flow cytometry assays, and inhibition against the 3CL protease and viral entry. Of particular interest are the two anti-HIV agents, one as an entry blocker and the other as a 3CL protease inhibitor (
K
i
= 0.6 μM).
Caste determination in a polyembryonic wasp involves inheritance of germ cells
Authors: Donnell David M. , Corley Laura S. , Chen Gang , Strand Michael R.
Published: June 2004

Social insects are characterized by the development of castes in which some colony members reproduce whereas others function as altruistic helpers. The conditional switch controlling caste formation usually involves environmental stimuli that act on processes that regulate development of individuals. Unlike other social species, embryos of polyembryonic wasps develop clonally to produce large numbers of genetically identical offspring and two morphologically distinct castes. All embryos in a clone exist in an identical environment, the host, yet develop into either reproductive larvae that mature into adult wasps or soldier larvae whose function is defense. Here, we report that caste determination inCopidosoma floridanuminvolves inheritance of germ cells. Expression of aC. floridanumhomolog (Cf-vas) of the germ cell marker Vasa indicated that the B4blastomere in four cell-stage embryos is specified as a primordial germ cell. Vas expression later in development further indicated that embryos developing into reproductive larvae possess primordial germ cells whereas embryos developing into soldier larvae do not. Ablation of the B4blastomere resulted in most broods containing only soldiers whereas ablation of other blastomeres produced broods containing both castes. These results indicate that soldier larvae are obligately sterile and reveal a previously unknown role for germ cells in caste formation.
Whole grains and human health
Authors: Slavin Joanne
Published: June 2004

Epidemiological studies find that whole-grain intake is protective against cancer, CVD, diabetes, and obesity. Despite recommendations to consume three servings of whole grains daily, usual intake in Western countries is only about one serving/d. Whole grains are rich in nutrients and phytochemicals with known health benefits. Whole grains have high concentrations of dietary fibre, resistant starch, and oligosaccharides. Whole grains are rich in antioxidants including trace minerals and phenolic compounds and these compounds have been linked to disease prevention. Other protective compounds in whole grains include phytate, phyto-oestrogens such as lignan, plant stanols and sterols, and vitamins and minerals. Published whole-grain feeding studies report improvements in biomarkers with whole-grain consumption, such as weight loss, blood-lipid improvement, and antioxidant protection. Although it is difficult to separate the protective properties of whole grains from dietary fibre and other components, the disease protection seen from whole grains in prospective epidemiological studies far exceeds the protection from isolated nutrients and phytochemicals in whole grains.
Nutrition and sarcopenia of ageing
Authors: Fujita Satoshi , Volpi Elena
Published: June 2004

Sarcopenia, the loss of muscle mass and function with ageing, is a multifactorial condition that slowly develops over decades and becomes a significant contributor to disability in the older population. Malnutrition and alterations in the muscle anabolic response to nutritional stimuli have been identified as potentially preventable factors that may significantly contribute to sarcopenia. In the present article we review the most recent findings regarding the role of nutritional factors in the development, prevention and treatment of sarcopenia. Specifically, we focus on the nutritional needs of the elderly; the age-related changes in the response of muscle protein metabolism to feeding and to the endogenous hormones released during feeding; and the role played by the splanchnic tissues in the response of muscle proteins to feeding. Finally, we review the issues relative to the potential use of nutritional therapies, including supplementation, for the prevention and treatment of sarcopenia.
Pharmacotherapies for problematic psychostimulant use: a review of current research
Authors: SHEARER JAMES , GOWING LINDA R.
Published: June 2004

This review summarizes the current status of clinical research on pharmacotherapies for problematic psychostimulant use. The use of psychostimulants, including amphetamine, cocaine and ecstasy, is increasingly a feature of Australian life as is the presentation of patients with psychostimulant disorders. A lack of experience, resources and treatment options have constrained the response of treatment services to such problems. Despite extensive research, particularly in the area of cocaine, no pharmacotherapy has been proven effective in the management of psychostimulant disorders. The harms associated with problematic psychostimulant use warrant further controlled research in innovative approaches integrated with psychosocial interventions.
Effect of pharmacologically induced smooth muscle activation on permeability in murine colitis
Authors: Zijlstra Freek J. , van Meeteren Marieke E. , Garrelds Ingrid M. , Meijssen Maarten A.C.
Published: June 2004

Background: Both intestinal permeability and contractility are altered in inflammatory bowel disease. Little is known about their mutual relation. Therefore, an in vitro organ bath technique was developed to investigate the simultaneous effects of inflammation on permeability and smooth muscle contractility in different segments of the colon.

Methods and materials: BALB/c mice were exposed to a 10% dextran sulphate sodium drinking water solution for 7 days to induce a mild colitis, while control mice received normal tap water. Intestinal segments were placed in an oxygenated organ bath containing Krebs buffer. Permeability was measured by the transport of the marker molecules 3H‐mannitol and 14C‐polyethyleneglycol 4000. Contractility was measured through a pressure sensor. Smooth muscle relaxation was obtained by salbutamol and l‐phenylephrine, whereas contraction was achieved by carbachol and 1‐(3‐chlorophenyl)‐biguanide.

Results: The intensity of mucosal inflammation increased throughout the colon. Also, regional differences were observed in intestinal permeability. In both normal and inflamed distal colon segments, permeability was diminished compared with proximal colon segments and the non‐inflamed ileum. Permeability in inflamed distal colon segments was significantly decreased compared with normal distal segments. Pharmacologically induced relaxation of smooth muscles did not affect this diminished permeability, although an increased motility positively affected permeability in inflamed and non‐inflamed distal colon.

Conclusions: Inflammation and permeability is inversely related. The use of pro‐kinetics could counteract this disturbed permeability and, in turn, could regulate the disturbed production of inflammatory mediators.
Exhaled nitric oxide in mylar balloons: influence of storage time, humidity and temperature
Authors: Bodini Alessandro , Pijnenburg Mariëlle W. H. , Boner Atillio L. , de Jongste Johan C.
Published: June 2004

Background: Mylar balloons are used to collect exhaled air for analysis of fractional nitric oxide concentration (FENO).

Aim: We studied the effect of storage conditions on the stability of nitric oxide (NO) in mylar balloons.

Methods: Exhaled air samples and calibration gases were stored in mylar balloons at 4, 21 and 37°C, with or without silica gel. NO was measured after 0, 6, 9, 24 and 48 h. Scheffe F‐tests were used to compare NO values. Results NO remained stable in balloons for 9 h at all temperatures, without silica gel. NO increased between 9 and 48 h, but only with low initial FENO. Silica gel increased variability.

Conclusions: FENO in mylar balloons is stable for at least 9 h. The storage temperature is not critical, but silica gel increases variability.
Natural HLA Class I Polymorphism Controls the Pathway of Antigen Presentation and Susceptibility to Viral Evasion
Authors: Zernich Danielle , Purcell Anthony W. , Macdonald Whitney A. , Kjer-Nielsen Lars , Ely Lauren K. , Laham Nihay , Crockford Tanya , Mifsud Nicole A. , Bharadwaj Mandvi , Chang Linus , Tait Brian D. , Holdsworth Rhonda , Brooks Andrew G. , Bottomley Stephen P. , Beddoe Travis , Peh Chen Au , Rossjohn Jamie , McCluskey James
Published: June 2004

HLA class I polymorphism creates diversity in epitope specificity and T cell repertoire. We show that HLA polymorphism also controls the choice of Ag presentation pathway. A single amino acid polymorphism that distinguishes HLA-B*4402 (Asp116) from B*4405 (Tyr116) permits B*4405 to constitutively acquire peptides without any detectable incorporation into the transporter associated with Ag presentation (TAP)-associated peptide loading complex even under conditions of extreme peptide starvation. This mode of peptide capture is less susceptible to viral interference than the conventional loading pathway used by HLA-B*4402 that involves assembly of class I molecules within the peptide loading complex. Thus, B*4402 and B*4405 are at opposite extremes of a natural spectrum in HLA class I dependence on the PLC for Ag presentation. These findings unveil a new layer of MHC polymorphism that affects the generic pathway of Ag loading, revealing an unsuspected evolutionary trade-off in selection for optimal HLA class I loading versus effective pathogen evasion.
Active Inhibition of Plasma Cell Development in Resting B Cells by Microphthalmia-associated Transcription Factor
Authors: Lin Ling , Gerth Andrea J. , Peng Stanford L.
Published: June 2004

B cell terminal differentiation involves development into an antibody-secreting plasma cell, reflecting the concerted activation of proplasma cell transcriptional regulators, such as Blimp-1, IRF-4, and Xbp-1. Here, we show that the microphthalmia-associated transcription factor (Mitf) is highly expressed in naive B cells, where it antagonizes the process of terminal differentiation through the repression of IRF-4. Defective Mitf activity results in spontaneous B cell activation, antibody secretion, and autoantibody production. Conversely, ectopic Mitf expression suppresses the expression of IRF-4, the plasma cell marker CD138, and antibody secretion. Thus, Mitf regulates B cell homeostasis by suppressing the antibody-secreting fate.
Gramicidin-perforated Patch Recording Revealed the Oscillatory Nature of Secretory Cl− Movements in Salivary Acinar Cells
Authors: Sugita Makoto , Hirono Chikara , Shiba Yoshiki
Published: June 2004

Elevations of cytoplasmic free calcium concentrations ([Ca2+]i) evoked by cholinergic agonists stimulate isotonic fluid secretion in salivary acinar cells. This process is driven by the apical exit of Cl− through Ca2+-activated Cl− channels, while Cl− enters the cytoplasm against its electrochemical gradient via a loop diuretic-sensitive Na+-K+-2Cl− cotransporter (NKCC) and/or parallel operations of Cl−-HCO3− and Na+-H+ exchangers, located in the basolateral membrane. To characterize the contributions of those activities to net Cl− secretion, we analyzed carbachol (CCh)-activated Cl− currents in submandibular acinar cells using the “gramicidin-perforated patch recording configuration.” Since the linear polypeptide antibiotic gramicidin creates monovalent cation-selective pores, CCh-activated Cl− currents in the gramicidin-perforated patch recording were carried by Cl− efflux via Cl− channels, dependent upon Cl− entry through Cl− transporters expressed in the acinar cells. CCh-evoked oscillatory Cl− currents were associated with oscillations of membrane potential. Bumetanide, a loop diuretic, decreased the CCh-activated Cl− currents and hyperpolarized the membrane potential. In contrast, neither methazolamide, a carbonic anhydrase inhibitor, nor elimination of external HCO3− had significant effects, suggesting that the cotransporter rather than parallel operations of Cl−-HCO3− and Na+-H+ exchangers is the primary Cl− uptake pathway. Pharmacological manipulation of the activities of the Ca2+-activated Cl− channel and the NKCC revealed that the NKCC plays a substantial role in determining the amplitude of oscillatory Cl− currents, while adjusting to the rate imposed by the Ca2+-activated Cl− channel, in the gramicidin-perforated patch configuration. By concerting with and being controlled by the cation steps, the oscillatory form of secretory Cl− movements may effectively provide a driving force for fluid secretion in intact acinar cells.
Block of Tetrodotoxin-resistant Na+ Channel Pore by Multivalent Cations
Authors: Kuo Chung-Chin , Chen Wan-Yu , Yang Ya-Chin
Published: June 2004

Tetrodotoxin-resistant (TTX-R) Na+ channels are much less susceptible to external TTX but more susceptible to external Cd2+ block than tetrodotoxin-sensitive (TTX-S) Na+ channels. Both TTX and Cd2+ seem to block the channel near the “DEKA” ring, which is probably part of a multi-ion single-file region adjacent to the external pore mouth and is involved in the selectivity filter of the channel. In this study we demonstrate that other multivalent transitional metal ions such as La3+, Zn2+, Ni2+, Co2+, and Mn2+ also block the TTX-R channels in dorsal root ganglion neurons. Just like Cd2+, the blocking effect has little intrinsic voltage dependence, but is profoundly influenced by Na+ flow. The apparent dissociation constants of the blocking ions are always significantly smaller in inward Na+ currents than those in outward Na+ current, signaling exit of the blocker along with the Na+ flow and a high internal energy barrier for “permeation” of these multivalent blocking ions through the pore. Most interestingly, the activation and especially the inactivation kinetics are slowed by the blocking ions. Moreover, the gating changes induced by the same concentration of a blocking ion are evidently different in different directions of Na+ current flow, but can always be correlated with the extent of pore block. Further quantitative analyses indicate that the apparent slowing of channel activation is chiefly ascribable to Na+ flow–dependent unblocking of the bound La3+ from the open Na+ channel, whereas channel inactivation cannot happen with any discernible speed in the La3+-blocked channel. Thus, the selectivity filter of Na+ channel is probably contiguous to a single-file multi-ion region at the external pore mouth, a region itself being nonselective in terms of significant binding of different multivalent cations. This region is “open” to the external solution even if the channel is “closed” (“deactivated”), but undergoes imperative conformational changes during the gating (especially the inactivation) process of the channel.
External Barium Affects the Gating of KCNQ1 Potassium Channels and Produces a Pore Block via Two Discrete Sites
Authors: Gibor Gilad , Yakubovich Daniel , Peretz Asher , Attali Bernard
Published: June 2004

The pore properties and the reciprocal interactions between permeant ions and the gating of KCNQ channels are poorly understood. Here we used external barium to investigate the permeation characteristics of homomeric KCNQ1 channels. We assessed the Ba2+ binding kinetics and the concentration and voltage dependence of Ba2+ steady-state block. Our results indicate that extracellular Ba2+ exerts a series of complex effects, including a voltage-dependent pore blockade as well as unique gating alterations. External barium interacts with the permeation pathway of KCNQ1 at two discrete and nonsequential sites. (a) A slow deep Ba2+ site that occludes the channel pore and could be simulated by a model of voltage-dependent block. (b) A fast superficial Ba2+ site that barely contributes to channel block and mostly affects channel gating by shifting rightward the voltage dependence of activation, slowing activation, speeding up deactivation kinetics, and inhibiting channel inactivation. A model of voltage-dependent block cannot predict the complex impact of Ba2+ on channel gating in low external K+ solutions. Ba2+ binding to this superficial site likely modifies the gating transitions states of KCNQ1. Both sites appear to reside in the permeation pathway as high external K+ attenuates Ba2+ inhibition of channel conductance and abolishes its impact on channel gating. Our data suggest that despite the high degree of homology of the pore region among the various K+ channels, KCNQ1 channels display significant structural and functional uniqueness.
Metal‐responsive transcription factor‐1 (MTF‐1) is essential for embryonic liver development and heavy metal detoxification in the adult liver
Authors: Wang Ying , Wimmer Ursula , Lichtlen Peter , Inderbitzin Daniel , Stieger Bruno , Meier Peter J. , Hunziker Lukas , Stallmach Thomas , Forrer Rhea , Rülicke Thomas , Georgiev Oleg , Schaffner Walter
Published: June 2004

Metal‐responsive transcription factor‐1 (MTF‐1) activates the transcription of metallothionein genes and other target genes in response to heavy metal load and other stresses such as hypoxia and oxidative stress. It also has an essential function during embryo‐genesis: targeted disruption of Mtf1 in the mouse results in lethal liver degeneration on day 14 of gestation. Here we studied Mtf1 knockout mice at embryonic and adult stages, the latter by means of conditional knockout. Hepatocytes from Mtf1 null mutant and wild‐type embryos were taken into culture on day 12.5 of gestation. Both initially appeared normal, but mutant cells were lost within a few days. Furthermore, Mtf1 null hepatocytes were poorly, if at all, rescued by cocultivation with wild‐type rat embryo hepatocytes, indicating a cell‐autonomous defect. When the Mtf1 gene was excised by Cre recombinase after birth in liver and bone marrow and to a lesser extent in other organs, mice were viable under non‐stress conditions but highly susceptible to cadmium toxicity, in support of a role of MTF‐1 in coping with heavy metal stress. An additional MTF‐1 function was revealed upon analysis of the hematopoietic system in conditional knockout mice where leukocytes, especially lymphocytes, were found to be severely underrepresented. Together, these findings point to a critical role of MTF‐1 in embryonic liver formation, heavy metal toxicity, and hematopoiesis.— Wang, Y., Wimmer, U., Lichtlen, P., Inderbitzin, D., Stieger, B., Meier, P. J., Hunziker, L., Stallmach, T., Forrer, T., Rülicke, T., Georgiev, O., Schaffner, W. Metal‐responsive transcription factor‐1 (MTF‐1) is essential for embryonic liver development and heavy metal detoxification in the adult liver. FASEB J. 18, 1071–1079 (2004)
Mitochondrial signals initiate the activation of c‐Jun N‐terminal kinase (JNK) by hypoxia‐reoxygenation
Authors: Dougherty Christopher J. , Kubasiak Lori A. , Frazier Donna P. , Li Huifang , Xiong Wen‐Cheng. , Bishopric Nanette H. , Webster Keith A.
Published: June 2004

C‐Jun N‐terminal kinase (JNK) is part of the mitogen‐activated protein kinase (MAPK) family of signaling pathways that are induced in response to extracellular stimuli. JNK is primarily a stress‐response pathway and can be activated by proinflammatory cyto‐ kines and growth factors coupled to membrane recep‐ tors or through non‐receptor pathways by stimuli such as heat shock, UV irradiation, protein synthesis inhibi‐ tors, and conditions that elevate the levels of reactive oxygen intermediates (ROI). The molecular initiators of MAPKs by non‐receptor stimuli have not been de‐ scribed. Ischemia followed by reperfusion or hypoxia with reoxygenation represents a condition of high oxidative stress where JNK activation is associated with elevated ROI. We show here that the activation of JNK by this condition is initiated in the mitochondria and requires coupled electron transport, ROI generation, and calcium flux. These signals cause the selective, sequential activation of the calcium‐dependent, pro‐ line‐rich kinase Pyk2 and the small GTP binding factors Rac‐1 and Cdc42. Interruption of these interactions with inactivated dominant negative mutant proteins, blocking calcium flux, or inhibiting electron transport through mitochondrial complexes II, III, or IV prevents JNK activation and results in a proapoptotic phenotype that is characteristic of JNK inhibition in this model of ischemia‐reperfusion. The signaling pathway is unique for the reoxygenation stimulus and provides a frame‐ work for other non‐receptor‐mediated pathways of MAPK activation.—Dougherty, C. J., Kubasiak, L. A., Frazier, D. P., Li, H., Xiong, W.‐C., Bishopric, N. H., Webster, K. A. Mitochondrial signals initiate the activation of c‐Jun N‐terminal kinase (JNK) by hypoxia‐ reoxygenation. FASEB J. 18, 1060–1070 (2004)
Multipoint inverse shape design of airfoils based on variable‐domain variational principle
Authors: Wu Zhe‐Min , Chen Chi , Liu Gao‐Lian
Published: June 2004

As a kind of free (unknown) boundary problem, inverse shape design of airfoils has attracted extensive attention in recent years. By variable‐domain variational theory, free boundary condition can be coupled with the governing equations for flow field, which makes it possible to calculate the flow field with the free boundary simultaneously. In this paper, the variational principle (VP) of 2D airfoil shape design problem is obtained from the basic dimensionless velocity potential equations for 2D compressible flow by using a systematic approach and variable‐domain variational formula. The deformable finite element method based on the VP is used to segmentally design airfoil at two design points (angles of attack) and four design points, respectively. The results show that the present method is highly effective and accurate for solving multipoint inverse problem of airfoils.
Fault diagnosis expert system for modern commercial aircraft
Authors: Wu Haiqiao , Liu Yi , Ding Yunliang , Qiu Yongqing
Published: June 2004

The objective of this paper is to develop an expert system according to the features of the fault diagnosis for modern commercial aircraft, which is based on case based reasoning and fuzzy logic. The development strategy of this kind of expert system is illustrated by the development process of an A340 fault diagnostic expert system. The key technology, which is involved in the system, is discussed, such as the construction of case base, the structure of indexes, the algorithm of retrieval and the management of case base.
Behaviour of composite wing T‐joints in hygrothermal environments
Authors: Rao V.V.S. , Krishna Veni K. , Sinha P.K.
Published: June 2004

This paper deals with the experimental investigation and non‐linear finite element analysis of composite wing T‐joints in hygrothermal environments. This study is concerned with T‐joints subjected to tension (pull‐out) force and their behaviour up to ultimate failure under bone dry and hygrothermal environments. The behaviour of such joints is complex due to the geometry of the joint configuration and laminated construction. T‐joints are also susceptible when exposed to moisture and temperature environments. As a consequence, the stiffness and strength properties of laminates because degraded. A three‐dimensional 20‐noded multidirectional composite element is developed using three‐dimensional super element concept to analyse both unstitched and stitched T‐joints. All the stress components are computed and the failure loads are evaluated using different failure criteria to get better insight into the behaviour of laminated composite wing T‐joints.
Laser processing of plastics
Authors: Rooks Brian
Published: June 2004

This paper focuses on some of the presentations given at a technical workshop on “Laser processing of polymer‐based materials”, organised by Association of Industrial Laser Users. Applications in cutting and welding are discussed and specifically how different combinations of polymer materials and laser types produce different results. Applications are described that include pre‐weakening of car trims for integrated airbags and “on the fly” scribing of web materials used in packaging. In several of these applications, robots play an important role in manipulating the laser beam.
PC robot controls drive sheet metal processing
Authors: Weisel Walter
Published: June 2004

Oak Ridge National Laboratory (ORNL, Oak Ridge, Tennessee, United States), the world‐known basic and applied research facility operated by the US Department of Energy, was tasked with reducing the cost to produce titanium aluminide sheet metal used to cover the outside of military aircraft and spacecraft. The ability to reduce costs is dependent upon advances in both materials and processes. This paper discusses the important breakthroughs ORNL has achieved in both materials and processes, especially the innovation in PC controls that provides an unprecedented level of versatility and flexibility that is user‐friendly, cost‐effective, and continuously upgradeable. This work is returning tangible results beyond the initial goal of achieving substantial cost savings.
Improving market helps innovation
Authors: Bloss Dick
Published: June 2004

Recent National Manufacturing Week Show in Chicago highlighted many new innovations. Assembly system designers can choose from new low inertia drives, more compact linear and rotary motors, innovative robots and pneumatic actuators along with new modular structural components which were featured at the show and in other recent introductions.
Robots and vision combine for application in plastics industries
Authors: Shafi Adil
Published: June 2004

This paper describes the benefits of vision guided robotics when applied in four industrial manufacturing case studies relating to plastics industries. These include trimming, welding, degating and deflashing operations.
A three‐DOF compliant micromotion stage with flexure hinges
Authors: Lu Tien‐Fu , Handley Daniel C. , Kuan Yong Yuen , Eales Craig
Published: June 2004

Micromanipulation has enabled numerous technological breakthroughs in recent years, from advances in biotechnology to microcomponent assembly. Micromotion devices commonly use piezoelectric actuators (PZT) together with compliant mechanisms to provide fine motions with position resolution in the nanometre or even sub‐nanometre range. Many multiple degree of freedom (DOF) micromotion stages have parallel structures due to better stiffness and accuracy than serial structures. This paper presents the development of a three‐DOF compliant micromotion stage with flexure hinges and parallel structure for applications requiring motions in micrometres. The derivation of a simple linear kinematic model of the compliant mechanism is presented and simulation results before and after calibration are compared with results from finite element (FE) modeling and experiments. The position control system, which uses an experimentally determined constant‐Jacobian, and its performance are also presented and discussed.
Enabling continuous improvement: a case study of implementation
Authors: de Jager Bertus , Minnie Chris , de Jager Johan , Welgemoed Marita , Bessant John , Francis Dave
Published: June 2004

Widespread recognition of the strategic imperative posed by a turbulent external environment has brought into focus a key challenge for firms – that of increasing involvement in innovation by the staff in the organisation. Much research has suggested that organisations that mobilise a large proportion of their staff to participate in innovation can make significant gains. Achieving this depends on a systematic process of organisational development in which the facilitative patterns of behavioural routines are extended and reinforced, so that they become a major culture change. This paper reports on progress with this organisational development methodology using a detailed case study of its use within a major mining company in South Africa. It makes use of a reference model framework to help structure and direct the change process towards enabling higher involvement in innovation. In particular it explores practical issues involved in moving a large organisation along a path of high involvement innovation.
Development of a team‐based framework for conducting self‐assessment of continuous improvement
Authors: Jørgensen Frances , Boer Harry , Gertsen Frank
Published: June 2004

The study presented in this article is based on two basic premises. First, successful continuous improvement (CI) is dependent on shop floor level involvement and participation in improvement efforts. Second, the term “self‐assessment” clearly implies that those whose performance is being measured, and who are involved in conducting the assessment process. Excerpts from longitudinal case studies in a single Danish manufacturing organization demonstrate how teams involved in the process of conducting self‐assessment of CI developed a better understanding of the basic principles of CI. Furthermore, the study shows how these principles relate to the teams’ own work processes, and a deeper understanding of their organization's strategy and objectives.
Balanced scorecards for strategic and sustainable continuous improvement capability
Authors: Dabhilkar Mandar , Bengtsson Lars
Published: June 2004

Illustrates how strategic continuous improvement (CI) capabilities were developed in three Swedish manufacturing companies that have implemented the Balanced Scorecard (BSC). A multiple case study was conducted; each company followed a unique team‐based CI strategy. Shows how the use of BSC was adapted to the specific characteristics that each of the CI strategies entail. Furthermore, shows that it could be difficult to sustain the capability that was developed. However, also finds that certain mechanisms in the management control system, as well as the presence of an advanced work organisation, may help in sustaining the strategic CI capability.
Exploring Six Sigma and CI capability development: preliminary case study findings on management role
Authors: Haikonen Arto , Savolainen Taina , Järvinen Pekka
Published: June 2004

Aims to explore the Six Sigma methodology as a method for developing CI capability. More specifically, the focus is on the role of management in the improvement of processes. Any type of organizational improvement process requires visible leadership and effective management to be successful. In high‐performance organizations, in particular, in which the Six Sigma methodology is currently gaining ground, managers allocate resources to the improvement activities they regard as crucial for the organization's success. Six Sigma is an improvement methodology that aims to increase business performance through a solid and accurate business focus. As the adoption of the Six Sigma methodology is still at an early stage in Finnish business life, presents preliminary case study findings. The findings imply that managers should adopt and internalize the Six Sigma philosophy first to give sufficient support to the implementation process. Furthermore, additional attention should be paid to the development of measurement systems and real time reporting systems, which is initially a managerial responsibility.
An enterprise collaborative management system – a case study of supplier relationship management
Authors: Choy K.L. , Lee W.B. , Lo Victor
Published: June 2004

In this paper, a server‐based enterprise collaborative management system using enterprise application integration technology is developed for trial implementation at Honeywell Consumer Products (Hong Kong) Limited, in the area of supplier relationship management. The system facilitates supplier selection using an integrative case‐based supplier selection and help desk approach to select the most appropriate suppliers, based on their past performance records from a case‐based warehouse. Discusses a case study to integrate Honeywell's supplier rating system and product coding system by case‐based reasoning technique to select preferred suppliers during the new product development process. Finds that the outsource cycle time from the searching of potential suppliers to the allocation of orders is greatly reduced while performance of suppliers can be monitored simultaneously.
Digital asset management in marketing communication logistics
Authors: Kovács Gyöngyi
Published: June 2004

Digital asset management as a technology for handling electronic material is used in different contexts for various technical purposes. Explores the effects of this technology on the marketing supply chain, being a new application area of digital asset management solutions. A conceptual framework is provided to describe marketing processes in the world of information technology and marketing communication logistics. Based on a literature review, possible benefits of digital asset management in this setting are presented. Anticipated benefits are evaluated in an indicative case study. The description of marketing supply chains leads to new insights for supply chain management.
Improving the interorganizational supply chain through optimization of information flows
Authors: Lewis Ira , Talalayevsky Alexander
Published: June 2004

Coordination is the management of dependencies between activities. Given that supply chains represent the functional integration of many interdependent activities associated with the flow of goods, coordination theory offers a framework for understanding and designing supply chains. Supply chains are separated into two distinct substructures: physical (dealing with the flow and storage of goods) and information (dealing with information associated with those goods). Optimization that alters the storage and movement of information and incorporates the impact of information technology leads to a distinct set of node connections and configurations for each substructure. Our analysis uses transaction cost economics to contrast the differences between structures infused with information technology and traditional supply chains.
Corporate performance management system in a devolved UK governmental organisation
Authors: Lawrie Gavin , Cobbold Ian , Marshall John
Published: June 2004

This paper is a case study exploring the design of a new corporate performance management (CPM) system for a UK government agency. The UK Environment Agency employs 11,000 staff in more than 40 discrete management units (comprising hierarchical, geographic and functional divisions). It is pursuing a strongly devolved approach to the development of strategic and operational plans. This paper describes work done by the agency to introduce a novel corporate management system based on best practice third‐generation balanced scorecard processes. The case describes how this system was deployed at the corporate level and then within directorate, regional and area level units. The work in total involved the design and implementation of 44 balanced scorecards across the organisation. Within this framework, the new CPM system was positioned as the key mechanism of control for the entire organisation. The CPM is, however, taking different forms across the organisation, reflecting the differences in balance between management and strategic control priorities faced by different management groups. This paper explores the reasons the agency undertook the redesign of the CPM system, and looks at the design approach used to develop a system of control compatible with the needs of the organisation's devolved business units. The paper reports that the experience to date has been positive, and concludes with recommendations on future areas of research and ways to approach the issue of measure selection and use within complex devolved organisations.
Influence of a Surface Bump or Groove on the Lubricating Performance and Dimple Phenomena in Simple Sliding Point EHL Contacts
Authors: Yang Peiran , Cui Jinlei , Kaneta Motohiro , Nishikawa Hiroshi
Published: June 2004

The influence of a transversely or longitudinally oriented surface bump or groove on the lubricating performance and dimple phenomena in the simple sliding point contact composed of a steel ball and a glass disk has been investigated theoretically with numerical solution of the thermal elastohydrodynamic lubrication (EHL) and experimentally with optical interferometry technique. Good agreement has been obtained between the theoretical and experimental results. It has also been discovered that the surface bump or groove is dangerously harmful to the lubricating performance and has a significant influence on the dimple phenomena.
A Numerical Study of Air-Bearing Slider Form-Factors
Authors: Thornton Brian H. , Bogy David B.
Published: June 2004

This paper presents a numerical study comparing the performance of air bearing slider form-factors. The air bearing slider and air bearing surface (ABS) design has gone through drastic changes in recent years in order to achieve the performance required by lower flying heights. In the past, improvements have been seen by scaling down the form-factors of air bearing sliders. The pico form-factor 1.25×1mm has been successfully used for several generations of products and the question arises—should the form-factor be scaled down further? The dynamic characteristics and flying-height modulation (FHM) performance of two different ABS designs in the pico and femto 0.82×0.66mm form-factors were numerically investigated. It was found that for the smaller form-factor designs, greater damping of the air bearing film and slider body system was achieved but with an undesirable decrease in modal frequencies. However, depending on the ABS design, beneficial dynamic properties can be achieved by scaling down the form-factor from pico to femto. Maximizing the total air bearing force (the sum of negative and positive) with a design featuring a large number of transverse pressure gradients can obtain high stiffness and damping. Geometric FHM was also investigated using both sinusoidal disk waviness and an actual measured disk topography. It was found that the FHM depends not only on the form-factor, but also on the ABS design. For long disk waviness wavelengths (longer than the slider body length, L), the FHM is proportional to Lβ where β was found to be between 2.6 and 4; hence, FHM is dependent on form-factor. For short disk waviness wavelengths, the FHM is a function of the ABS design and flying attitude and not form-factor. A disk waviness wavelength of 3 mm demarks the transition above which the FHM is a function of form-factor and below which the FHM is a function of the ABS design and the superposition of these two effects compose the geometric FHM. Simulations with an actual measured disk topography showed that the femto form-factor exhibited 22–32 percent less FHM than the pico form-factor for a similar design. However, by changing the ABS design, 35–40 percent less FHM was achieved within the same form-factor. By scaling down a pico slider to a femto slider, we do not necessarily achieve enhanced overall performance. Significant performance improvements in the pico form-factor can be attained if the ABS is properly designed. However, in designing a dynamically stable and low FHM air bearing slider a femto slider ultimately yields better performance when care is taken in designing the ABS.
The Effect of Dent Size on the Pressure Distribution and Failure Location in Dry Point Frictionless Rolling Contacts
Authors: Howell M. B. , Rubin C. A. , Hahn G. T.
Published: June 2004

Finite element simulation is performed for rolling contact over four different size spherical dents. Two rolling contacts are simulated using a portion of a sphere as a counter-face to the dented half-space. The effect of dent size on the pressure distribution and fatigue failure location for dry point contact is studied. The material model used was adjusted to match both the stress amplitude versus strain range curve and ratchetting experimental data for 52100 bearing steel.
Shape Design for Surface of a Slider by Inverse Method
Authors: Cheng Chin-Hsiang , Chang Mei-Hsia
Published: June 2004

The aim of this study is to design the shapes of the surfaces of sliders to meet the load demands specified by the designers. A direct problem solver is built to provide solutions for pressure distribution between the slider and the rotor for various geometric conditions and load demands. The direct problem solver is then incorporated with the conjugate gradient method so as to develop an inverse method for the slider surface shape design. The specified load demands considered in this study are categorized into two kinds: (1) specified pressure distribution within the fluid film and (2) specified resultant forces plus specified centers of load. Several cases at various bearing numbers are tested to demonstrate the validity of the inverse shape design approach. Results show that the surface shape of a slider can be designed efficiently to comply with the specified load demands considered in the present study by using the inverse method.