bluuebunny/crossref_metadata_2025 huggingface dataset:
Proteins involved in synaptic vesicle trafficking
Authors: Augustine George J. , Burns Marie E. , DeBello William M. , Hilfiker Sabine , Morgan Jennifer R. , Schweizer Felix E. , Tokumaru Hiroshi , Umayahara Keiko
Published: September 2004

Neurotransmitter release relies on a series of synaptic vesicle trafficking reactions. We have determined the molecular basis of these reactions by microinjecting, into ‘giant’ nerve terminals of squid, probes that interfere with presynaptic proteins. These probes affect neurotransmitter release and disrupt nerve terminal structure. From the nature of these lesions, it is possible to deduce the roles of individual proteins in specific vesicle trafficking reactions. This approach has revealed the function of more than a dozen presynaptic proteins and we hypothesize that neurotransmitter release requires the coordinated action of perhaps 50–100 proteins.
Functional domains within the degenerin/epithelial sodium channel (Deg/ENaC) superfamily of ion channels
Authors: Benos Dale J. , Stanton Bruce A.
Published: September 2004

Application of recombinant DNA technology and electrophysiology to the study of amiloride‐sensitive Na+ channels has resulted in an enormous increase in the understanding of the structure‐function relationships of these channels. Moreover, this knowledge has permitted the elucidation of the physiological roles of these ion channels in cellular processes as diverse as transepithelial salt and water movement, taste perception, volume regulation, nociception, neuronal function, mechanosensation, and even defaecation. Although members of this ever‐growing superfamily of ion channels (the Deg/ENaC superfamily) share little amino acid identity, they are all organized similarly, namely, two short N‐ and C‐termini, two short membrane‐spanning segments, and a very large extracellular loop domain. In this brief Topical Review, we discuss the structural features of each domain of this Deg/ENaC superfamily and, using ENaC as a model, show how each domain relates to overall channel function.
Molecular insights into the physiology of the ‘thin film’ of airway surface liquid
Authors: Boucher R. C.
Published: September 2004

The epithelia that line the airways of the lung exhibit two general functions: (1) airway epithelia in all regions ‘defend’ the lung against infectious and noxious agents; and (2) airway epithelia in the proximal regions replenish water lost from airway surfaces, i.e. the ‘insensible water loss’, consequent to conditioning inspired air. How airway epithelia perform both functions, and co‐ordinate them in health and disease, is the subject of this review.
Neurosecretory cells without neurosecretion: evidence of an independently regulated trait of the cell phenotype
Authors: Malosio M. L. , Benfante R. , Racchetti G. , Borgonovo B. , Rosa P. , Meldolesi J.
Published: September 2004

Neurosecretion competence is a fundamental property that enables differentiated neurones and professional neurosecretory cells to store neurotransmitters and hormones in specialized organelles, the synaptic‐like vesicles and dense granules, and to release them by regulated exocytosis. In our laboratory, the study of rat phaeochromocytoma (PC12) clones that fail to express the above organelles or any other components involved in neurosecretion, whilst maintaining most of the general markers of the parental population, has served to demonstrate that this trait is controlled independently from the rest of the phenotype. The present review focuses on recent advances in elucidating the molecular mechanisms governing neurosecretion competence. Moreover, the opportunities that such neurosecretion‐defective PC12 clones offer for the investigation of new aspects of regulated exocytosis and the localization of its components are summarized.
Salivary carbonic anhydrase isoenzyme VI
Authors: Kivelä Jyrki , Parkkila Seppo , Parkkila Anna‐Kaisa , Leinonen Jukka , Rajaniemi Hannu
Published: September 2004

The carbonic anhydrases (CAs) participate in the maintenance of pH homeostasis in various tissues and biological fluids of the human body by catalysing the reversible reaction CO2+ H2O ⇌ HCO3−+ H+ (Davenport & Fisher, 1938; Davenport, 1939; Maren, 1967). Carbonic anhydrase isoenzyme VI (CA VI) is the only secretory isoenzyme of the mammalian CA gene family. It is exclusively expressed in the serous acinar cells of the parotid and submandibular glands, from where it is secreted into the saliva. In this review, we will discuss recent advances in research focused on the physiological role of salivary CA VI in the oral cavity and upper alimentary canal.
Archaeometry and materiality: materials‐based analysis in theory and practice*
Authors: Jones A.
Published: September 2004

Due to the diversity of contemporary archaeology, the aims and approaches of archaeological scientists and archaeological theorists are often at odds. I suggest that this position is problematic, both intellectually and methodologically, as both groups are fundamentally engaged in the same task: an understanding of past societies through the medium of material culture.

This paper offers a review of the intellectual positions of both groups, with a brief discussion of the history of archaeological theory and an appraisal of its current trajectory. I will discuss how and why contemporary theoretical perspectives have fundamentally diverged from the perspectives of archaeological scientists and how the recent theoretical emphasis upon materiality offers a rapprochement between theoreticians and archaeological scientists.
Chemical characterization of ancient pottery from sudan by x‐ray fluorescence spectrometry (xrf), electron microprobe analyses (empa) and inductively coupled plasma mass spectrometry (ICP–MS)*
Authors: Klein M. , Jesse F. , Kasper H. U. , Gölden A.
Published: September 2004

Sixty‐four sherds and seven natural clays from prehistoric sites in northwestern Sudan have been submitted to petrological and chemical analysis using XRF spectrometry, EMPA and ICP–MS. According to their texture, the sherds form five different groups. The high contents of P2O5 (more than 0.5 wt%) discerned in 19 samples and the variation of the P2O5 content in two samples of the same vessel can be explained by post‐depositional processes or by the ancient organic contents (e.g., milk) of the vessel. Chemical classification of the pottery bulk suggests that vessels were made locally, as only sherds from the same area show homogeneity of data.
T‐cell‐derived malignant lymphoma in the boxer breed
Authors: Lurie D. M. , Lucroy M. D. , Griffey S. M. , Simonson E. , Madewell B. R.
Published: September 2004

The boxer breed of dog is at high risk for a variety of neoplasms including lymphoma. In this observational study, tissue sections from boxer dogs with lymphoma were immunostained for T and B lymphocyte distinction, and the results compared with similar studies carried out on lymphoma tissues from temporally selected cohorts of golden retriever and rottweiler dogs. The frequency of T‐cell lymphomas was significantly (P < 0.001 for all comparisons) higher in the boxers than in the rottweilers or golden retrievers. We are unaware of other reports linking immunotype of canine lymphoma with breed; whether other brachycephalic breeds of dogs have a similar preponderance of T‐cell lymphoma awaits further study.
Transforming open mining pits into fish farms: Moving towards sustainability
Authors: Otchere Fred A. , Veiga Marcello M. , Hinton Jennifer J. , Farias Renato A. , Hamaguchi Robert
Published: September 2004

The legacy of mining activities has typically been land ‘returned to wildlife’, or, at some sites, degraded to such an extent that it is unsuitable for any alternate use. Progress towards sustainability is made when value is added in terms of the ecological, social and economic well‐being of the community. In keeping with the principles of sustainable development, the innovative use of flooded open pits and tailings impoundments as commercial, recreational or ornamental fish farms should be considered in some locations, as it could make a significant contribution to the social equity, economic vitality and environmental integrity of mining communities. This article highlights the growing significance of aquaculture and explores the benefits and barriers to transforming flooded pits and impoundments into aquaculture operations. Among other benefits, aquaculture may provide a much‐needed source of revenue, employment and, in some cases, food to communities impacted by mine closure. Further, aquaculture in a controlled closed environment may be more acceptable to critics of fish farming who are concerned about fish escapes and viral transmissions to wild populations. Despite the potential benefits, aquaculture in flooded pits and impoundments is not without its complications — it requires a site‐specific design approach that must consider issues ranging from metals uptake by fish, to the long‐term viability of the aquatic system as fish habitat, to the overall contribution of aquaculture to sustainability.
New and innovative therapies for Behcet's disease
Authors: DAVATCHI Fereydoun
Published: September 2004

Background:  Behcet's disease (BD) is a vasculitis progressing by attacks and remissions. Not all patients will respond even to the classical treatments. New treatments are emerging with the hope to overcome this failure.

Biologic agents:  Interferon‐α (IFN‐α), anti‐tumour necrosis factor‐α (TNF‐α), and tolerization have been used in BD.

IFN‐α is mainly used for ocular manifestations of BD. The result seems impressive, 92% of cases had good or excellent results. It was less impressive for mucocutaneous and joint manifestations. The dosage is 6–9 million IU/day for 4 weeks, then 4.5 million daily for 4 weeks, and then 3 million/day. The maintenance dose is 3 millions, three times/week, to continue for 8 weeks after complete remission.

Etanercept (anti‐TNF‐α) was effective in mucocutaneous lesions of BD at the dosage of 25 mg twice weekly for 3 months (double‐blind control study). Attacks relapsed after discontinuation. Etanercept was ineffective in ocular lesions (open study).

Infliximab (anti‐TNF‐α) was very effective in many studies of ocular lesions. It dramatically suppressed the inflammatory attack. The dosage is one injection of 5 mg/kg (intravenous infusion) at weeks 0, 2, 6, and then every 8 weeks.

Tolerization with oral administration of HSP peptide 336–351 seems to protect from uveitis relapse.

Pentoxifylline is not particularly effective unless for oral aphthae (50% response rate).

Pimecrolimus ointment may be of help in resistant genital aphthosis, reducing the healing time.
Improvement in rheumatoid heart disease following infliximab in a patient with long standing rheumatoid arthritis
Authors: HON Yoon Kam
Published: September 2004

This report describes a 60‐year‐old woman with chronic active rheumatoid arthritis (RA) with rheumatoid heart disease treated successfully with infliximab. The patient had a history of rheumatoid heart disease, presented with cardiac failure and also had active polyarthritis. Two‐dimensional echocardiogram (2‐DE) showed ejection fraction (EF) of 35%. Infliximab therapy at 3 mg/kg was given to the patient, at weeks 0, 2, and 6 and then 8‐weekly. There was complete remission of her joint symptoms and the EF improved to 55%. Patients with active arthritis and rheumatoid heart disease can benefit from infliximab.
The Families and Democracy Project
Authors: Doherty William J. , Carroll Jason S.
Published: September 2004

The Families and Democracy Project moves family therapists and other professionals into the community via a critique of traditional provider/consumer models of family services, a set of principles about the civic engagement of families in partnership with professionals, and a set of public practices for working on community problems. We describe the Families and Democracy model and three specific projects. We distinguish the model from traditional hierarchical and collaborative models of working with families. And we discuss lessons we have learned, and our plans to take this work to its next developmental stage.
Healing Internalized Racism: The Role of a Within‐Group Sanctuary Among People of African Descent
Authors: Watts‐Jones Dee
Published: September 2004

This article addresses the role of a “within‐group” sanctuary for healing internalized racism among people of African descent. Internalized racism is distinguished from racism, juxtaposing the different experience of whose who are oppressed and those who are privileged br racism. It is suggested that a context cosisting exclusivel of persons of African descent can provided on opticmally safe space for initial stages of healing from internlaized racism. The anxiety that a collective of African descendants can generate amont whites, and subsequently among those of African descent, is examined by raising questions as to its possible meanings. Whites are encouraged to use their privilege to support such self‐determined sanctuaries, rather than to obstruct them. People of African descent are encouraged to tolerate the anxiety that can be generated without “changing back,” and to examine whether internalized racism is also implicated.
Can the Family Assessment Device (FAD) Be Used with School Aged Children?
Authors: Bihum Joan T. , Wamboldt Marianne Z. , Gavin Lesile A. , Wamboldt Frederick S.
Published: September 2004

This article examines the usefulness of the Family Assessment Device (FAD) in assessing family functioning with school‐aged children (under 12 years of age) compared to children 12 and older and mothers. FAD reports from 194 children with asthma (132 under 12 years; 62 12 years and older) were evaluated in comparison to mothers' FAD reports as well as mothers' reports on two other family functioning measures: the Family Inventory of Life Events (FILE) and the Impact on Family (IOF) scale, both relevant to functioning in families with children with asthma. Although FAD scale reliabilities were lowest in younger children (α=.48‐.79), good concurrent validity was found with mothers' reports on the three different measures of family functioning. Older childrens' FAD scales showed good reliability (> .70) but poorer agreement with the various maternal measures. With modifications to make items more structured and simplified, the FAD could be tried with younger children, although documentation of improved reliability is needed before more widespread use with school‐aged children is advocated. The measure already shows good agreement with maternal report in this younger age group, which likely would be strengthened with improved reliability. FAD reports in older children correlated less well with maternal measures, but may represent nonredundant information on family health from an independent perspective and are worth considering in addition to mothers' perspectives.
Tissue‐engineered injectable bone regeneration for osseointegrated dental implants
Authors: Yamada Yoichi , Ueda Minoru , Naiki Takahito , Nagasaka Tetsuro
Published: September 2004

Abstract: The present study investigated a correlation between osseointegration in dental implants and an injectable tissue‐engineered bone, using mesenchymal stem cells (MSCs) and platelet‐rich plasma (PRP). Initially, the teeth in the mandible region were extracted and the healing period was 1 month. Bone defects on both sides of the mandible were prepared with a trephine bar. The defects were implanted with graft materials as follows: PRP, dog MSCs (dMSCs), and PRP, autogenous particulate cancellous bone and marrow (PCBM), and control (defect only). Two months later, the animals were evaluated by histology, and at the same time dental implants were installed. Two months later, the animals were sacrificed and nondecalcified sections were evaluated histologically and histometrically. According to the histological observations, the dMSCs/PRP group had well‐formed mature bone and neovascularization, compared with the control (defect only) and PRP groups, as was the same for the PCBM group. A higher marginal bone level was observed around implants with PRP, PCBM, and dMSCs/PRP compared with the control. Furthermore, the values describing the amount of bone–implant contact (BIC) at the bone/implant interface were significantly different between the PRP, PCBM, dMSCs/PRP, and control groups. Significant differences were also found between the dMSCs/PRP and control groups in bone density. The findings of this experimental study indicate that the use of a mixture of dMSCs/PRP results in good results such as the amount of BIC and bone density comparable with that achieved by PCBM.
Mandibular two‐implant telescopic overdentures
Authors: Heckmann Siegfried M. , Schrott Alexander , Graef Friedrich , Wichmann Manfred G. , Weber Hans‐Peter
Published: September 2004

Abstract: To stabilize mandibular overdentures in edentulous patients, various connector types which can be attached to between two and four implants placed in the anterior mandible are possible. Treatment using non‐rigid telescopic connectors on two interforaminal implants for overdenture stabilization began in 1989. The objective of this study is to investigate soft‐ and hard‐tissue conditions as well as prosthesis function after a period of 10 years. This also involved an evaluation of correlations between radiographic and clinical parameters. Twenty‐three subjects with 46 interforaminal implants (ITI solid screw implants, 12 mm in length, 4.1 mm in diameter; 10.4 years in situ, range, 8–12.8 years) were investigated. Modified plaque index (mPI), sulcus fluid flow rate (SFFR), modified sulcus bleeding index (mBI), probing depth (PD), distance from implant crown margin to the coronal border of the peri‐implant mucosa (DIM), attachment level (AL), width of keratinized mucosa (KM), Periotest® values (PTVs) and prosthesis function were evaluated. In the radiographic evaluation, the distance between implant shoulder and first crestal bone–implant contact (DIB) in mm and the horizontal bone loss (HBL) in mm were measured. The relatively high mPI scores (mean, 0.82; score, 0 in 44.4%; SD, 0.83) did not result in increased SFFR scores (mean, 12; min, 3, max, 38; SD, 7.43) or higher mBI scores (mean, 0.35; score, 0 in 70.8%; SD, 0.59), which was commensurate with healthy peri‐implant mucosa. A mean PD value of 2.15 mm (min, 1 mm; max, 5 mm; SD, 0.96) and a mean DIM value of 0.28 mm (min, 0 mm; max, 2 mm; SD, 0.52) were measured. The implants were stable, showing a mean Periotest® value of −1.91 (max, 02, min, −6; SD, 1.76). A mean DIB of 3.19±0.95 mm (range, 1.3–5.16 mm) and a mean HBL of 1.6±1.52 mm (range, 0.28–8.33 mm) were calculated. A correlation was found between DIB and the parameters SFFR (P=0.060), DIM (P=0.042), AL (P=0.050) and especially PTV (P<0.01), leading to the assumption that these clinical parameters may be useful indicators of peri‐implant bone loss. The results of the 10‐year follow‐up examination show that non‐rigid telescopic connectors with two interforaminal implants for overdenture stabilization appear to be an efficient and effective long‐term treatment modality in severely resorbed edentulous mandibles. Particularly in geriatric patient treatment this concept may provide advantages in terms of handling, cleaning and long‐term satisfaction.
Insulin Stimulates the Entry of GLUT4 into the Endosomal Recycling Pathway by a Quantal Mechanism
Authors: Coster Adelle C. F. , Govers Roland , James David E.
Published: September 2004

The insulin‐sensitive glucose transporter GLUT4 mediates the uptake of glucose into adipocytes and muscle cells. In this study we have used a novel 96‐well plate fluorescence assay to study the kinetics of GLUT4 trafficking in 3T3‐L1 adipocytes. We have found evidence for a graded release mechanism whereby GLUT4 is released into the plasma membrane recycling system in a nonkinetic manner as follows: the kinetics of appearance of GLUT4 at the plasma membrane is independent of the insulin concentration; a large proportion of GLUT4 molecules do not participate in plasma membrane recycling in the absence of insulin; and with increasing insulin there is an incremental increase in the total number of GLUT4 molecules participating in the recycling pathway rather than simply an increased rate of recycling. We propose a model whereby GLUT4 is stored in a compartment that is disengaged from the plasma membrane recycling system in the basal state. In response to insulin, GLUT4 is quantally released from this compartment in a pulsatile manner, leaving some sequestered from the recycling pathway even in conditions of excess insulin. Once disengaged from this location we suggest that in the continuous presence of insulin this quanta of GLUT4 continuously recycles to the plasma membrane, possibly via non‐endosomal carriers that are formed at the perinuclear region.
Acid phosphatase in cheese
Authors: AKUZAWA Ryozo , FOX Patrick F.
Published: September 2004

The combined action of proteinases/peptidases and acid phosphatases on phosphorylated proteins/peptides could be important for cheese quality. It seems that acid phosphatase activity in cheese originates from milk and microorganisms. Bovine milk contains more than one acid phosphatase, which are distributed between the cream and skim milk. The properties of two enzymes isolated from butter milk and skim milk are different. In general, acid phosphatase, especially that from starter organisms is very heat stable. The dephosphorylation of casein and phosphopeptides is of interest in cheese ripening. It has been suggested that acid phosphatases from both skim milk and lactic acid bacteria contribute to dephosphorylation of phosphopeptides in cheese, which are produced from casein by coagulant, indigenous milk proteinase and microbial proteinases during cheese ripening.
Oral thyroxine administration mimics photoperiodically induced gonadal growth in Japanese quail
Authors: YASUO Shinobu , EBIHARA Shizufumi , YOSHIMURA Takashi
Published: September 2004

Most temperate‐zone animals are seasonal breeders. In a previous study, it was found that light‐induced hormone conversion of thyroxine (T4) prohormone to active 3,5,3′‐triiodothyronine (T3) in the mediobasal hypothalamus regulates photoperiodic response of gonads in Japanese quail. Here the effect of T4 or T3, administered in drinking water, on testicular growth in the Japanese quail kept under short days is shown. Testicular length was significantly increased in birds given T4 at doses of 4, 8 and 10 mg/L, while any dose of T3 had little effect on testicular growth. High doses (8 and 10 mg/L) of T4 and T3 resulted in high mortality and/or reduction of bodyweight. Among all of the treatment, 4 mg/L of T4 was the most effective on photoperiodic testicular growth, which caused little reduction in bodyweight. These data provide a new conventional method for promoting gonadal growth under short days.
Effects of fallen snow on the voluntary intake and grazing behavior of Hokkaido native horses in winter woodland with underlying Sasa senanensis
Authors: KAWAI Masahito , HISANO Hanako , YABU Yumiko , YABU Naoki , MATSUOKA Sakae
Published: September 2004

The intake, digestibility, and grazing behavior of Hokkaido native horses were investigated in winter woodland with underlying Sasa senanensis. Twenty Hokkaido native horses were grazed in a woodland (8.52 ha) for 14 days in December (snowy; 20 cm of snow fall) and in November (non‐snowy) of the next year. Three mares (360 kg of average bodyweight) were used in each experiment. The fecal collection, used to investigate the intake and digestibility by the double‐indicator method, and behavioral observations were carried out for 24 h on the 6th day in each experiment. During the snowy and non‐snowy periods, the dry matter intakes of sasa foliage were 7.3 and 9.6 kg/d, respectively, which is 2.1 and 2.7% when expressed as a percentage of bodyweight. The apparent digestibility of nutrients and energy released during the snowy and non‐snowy periods were similar. The proportions of digestible energy intakes to maintenance requirement in the mares were 119 and 164% during the snowy and non‐snowy periods, respectively. Their bodyweight remained constant during the non‐snowy period; however, a slight loss in their bodyweight was observed during the snowy period. The duration of grazing on sasa foliage was 416 and 544 min/d during the snowy and non‐snowy periods, respectively, the daily grazing area of the mares during these periods was 2.0 and 5.1 ha, respectively. In other words, the area during the snowy period was smaller than that during the non‐snowy period (P < 0.05). Fallen snow, even with a depth of approximately 20 cm, inhibited the grazing behavior and intake of sasa foliage by Hokkaido native horses grazing in winter woodland pasture.
Advanced treatment of swine wastewater by electrodialysis with a tubular ion exchange membrane
Authors: FUKUMOTO Yasuyuki , HAGA Kiyonori
Published: September 2004

To remove the excess nitrogen and phosphorus in swine wastewater, an electrodialysis technique was applied to an advanced treatment method. The laboratory‐scale swine wastewater treatment system constructed for the present study consisted of an activated sludge process, as the main treatment unit, and electrodialysis, as an advanced treatment unit. This system was operated for 200 days and the processing performance was evaluated. By electrodialysis, approximately 99% of NO3– and PO43– in the activated sludge‐treated water (AT solution) was removed during operation. Furthermore, electrodialysis decreased the color density of the AT solution at a rate of 58%. The advanced treatment of swine wastewater by electrodialysis proved to be an efficient technique to remove excess nitrogen and phosphorus, and decrease color density.
The role of endogenous opioids in the control of gastrointestinal motility: predictions from in vitro modelling
Authors: Sanger G. J. , Tuladhar B. R.
Published: September 2004

Gastrointestinal motility can be assessed in vitro by investigating the effects of drugs or gene knockouts on intestinal propulsion, and on neurone‐mediated responses evoked by electrical field stimulation (EFS). The latter predominantly measure enteric motor activity and can detect prokinetic activity of exogenous agents. Some evidence suggests that naloxone has prokinetic activity when evaluated for an ability to modulate responses to EFS, but the effects are inconsistent across different species or intestinal regions. Models of intestinal peristalsis measure an integrated sensory‐motor nerve function and possess more intact neuro‐neuronal connections. In such preparations, the effects of naloxone also suggest a prokinetic property but again, this is inconsistent. By contrast, consistent prokinetic activity of naloxone is apparent in models where peristalsis is compromised by drug‐induced suppression of motor nerve activity or by modulation of endogenous processes using receptor antagonists or inappropriate intraluminal distension. These data suggest that endogenous opioids play little or no role in normal intestinal physiology, but suppress intestinal motility when motor function is compromised. Consequently, drugs that antagonize opioid receptors may exert prokinetic activity in conditions where intestinal motility is reduced, such as constipation. Further work is required to elucidate the opiate receptor(s) involved.
The Near-Tip Stress Intensity Factor for a Crack Partially Penetrating an Inclusion
Authors: Li Zhonghua , Yang Lihong
Published: September 2004

When a crack is lodged in an inclusion, the difference between the elastic modulus of the inclusion and matrix material will cause the near-tip stress intensity factor to be greater or less than that prevailing in a homogeneous material. A method is derived for calculation of the near-tip stress intensity factor for the inclusion with arbitrary shape. The derivation of the fundamental formula is based on the transformation toughening theory. The equivalent transformation strain contributed from modulus difference between inclusion and matrix is calculated from Eshelby equivalent inclusion approach. As validated by numerical examples, the developed formula has excellent accuracy.
Analysis of the M-Integral in Plane Elasticity
Authors: Chen Y. Z. , Lee Kang Yong
Published: September 2004

In this paper, analysis of the M-integral in plane elasticity is carried out. An infinite plate with any number of inclusions and cracks and with any applied forces and remote tractions is considered. To study the problem, the mutual work difference integral (abbreviated as MWDI) is introduced, which is defined by the difference of works done by each other stress field on a large circle. The concept of the derivative stress field is also introduced, which is a real elasticity solution and is derived from the physical stress field. It is found that the M-integral on a large circle is equal to a MWDI from the physical stress field and a derivative stress field. Finally, the expression for M-integral on a large circle is obtained. The variation for the M-integral with respect to the coordinate transformation is addressed. An illustrative example for the use of M-integral is presented.
Impermeable Crack and Permeable Crack Assumptions, Which One is More Realistic?
Authors: Wang Bao-Lin , Mai Yiu-Wing
Published: September 2004

This paper investigates the applicability and effect of the crack-free electrical boundary conditions in piezoelectric fracture. By treating flaws in a medium as notches with a finite width, the results from different electrical boundary condition assumptions on the crack faces are compared. It is found that the electrically impermeable boundary is a reasonable one for engineering problems. Unless the flaw interior is filled with conductive media, the permeable crack assumption may not be directly applied to the fracture of piezoelectric materials in engineering applications.
Aerodynamic Performance of a Very High Lift Low Pressure Turbine Blade With Emphasis on Separation Prediction
Authors: Houtermans Re´gis , Coton Thomas , Arts Tony
Published: September 2004

The present paper is based on an experimental study of a front-loaded very high lift, low pressure turbine blade designed at the VKI. The experiments have been carried out in a low-speed wind tunnel over a wide operating range of incidence and Reynolds number. The aim of the study is to characterize the flow through the cascade in terms of losses, mean outlet flow angle, and secondary flows. At low inlet freestream turbulence intensity, a laminar separation bubble is present, and a prediction model for a separated flow mode of transition has been developed.
Dynamic Stability of Disks With Periodically Varying Spin Rates Subjected to Stationary In-Plane Edge Loads
Authors: Young T. H. , Wu M. Y.
Published: September 2004

This paper presents an analysis of dynamic stability of an annular plate with a periodically varying spin rate subjected to a stationary in-plane edge load. The spin rate of the plate is characterized as the sum of a constant speed and a small, periodic perturbation. Due to this periodically varying spin rate, the plate may bring about parametric instability. In this work, the initial stress distributions caused by the periodically varying spin rate and the in-plane edge load are analyzed first. The finite element method is applied then to yield the discretized equations of motion. Finally, the method of multiple scales is adopted to determine the stability boundaries of the system. Numerical results show that combination resonances take place only between modes of the same nodal diameter if the stationary in-plane edge load is absent. However, there are additional combination resonances between modes of different nodal diameters if the stationary in-plane edge load is present.
Modeling the Rotation of Orthotropic Axes of Sheet Metals Subjected to Off-Axis Uniaxial Tension
Authors: Tong Wei , Tao Hong , Jiang Xiquan
Published: September 2004

A simplified version of a newly developed anisotropic plasticity theory is presented to describe the anisotropic flow behavior of orthotropic polycrystalline sheet metals under uniaxial tension. The theory is formulated in terms of the intrinsic variables of principal stresses and a loading orientation angle and its uniaxial tension version requires a non-quadratic stress exponent and up to five anisotropic material functions of the loading orientation angle to specify a flow condition, a flow rule for plastic strain rates, a flow rule for macroscopic plastic spin, and an evolution law of isotropic hardening. In this investigation, the proper analytical form and the associated parameter identification of the anisotropic material functions defining the flow rule of macroscopic plastic spin are discussed for sheet metals with persistent but rotated orthotropic symmetry axes under off-axis uniaxial tension. It is shown that the proposed flow rule of macroscopic plastic spin can successfully model the experimental data on the rotation of orthotropic symmetry axes in the three sheet metals reported, respectively, by Boehler et al. (Boehler and Koss, 1991, Advances in Continuum Mechanics, O. Bruller et al., eds., Springer, Heidelberg, pp. 143–158; Losilla, Boehler, and Zheng, 2000, Acta Mech. 144, pp. 169–183); Kim and Yin (1997, J. Mech. Phys. Solids 45, pp. 841–851); and Bunge and Nielsen (1997 Int. J. Plasticity 13, pp. 435–446).
On Some Peculiar Aspects of Axial Motions of Closed Loops of String in the Presence of a Singular Supply of Momentum
Authors: O’Reilly Oliver M. , Varadi Peter C.
Published: September 2004

We consider the dynamics of a closed loop of inextensible string which is undergoing an axial motion. At each instant, one material point of the string is in contact with a singular supply of linear momentum (also known as an external constraint). Several peculiar features of this problem which have not been previously discussed are presented. These include the possible presence of an arbitrary number of kinks, the vanishing nature of the singular supply of momentum, and the critical nature of the tension in the string. When the linear momentum is supplied by a mass-spring-dashpot system, we are also able to establish an exact expression for the frequency of the resulting vibrations, prove that dissipation cannot be present, show that these vibrations only occur for discrete speeds of axial motion, and establish that Coulomb friction is absent.
Generalized Linear Product Homotopy Algorithms and the Computation of Reachable Surfaces
Authors: Su Hai-Jun , McCarthy J. Michael , Watson Layne T.
Published: September 2004

In this paper, we apply a homotopy algorithm to the problem of finding points in a moving body that lie on specific algebraic surfaces for a given set of spatial configurations of the body. This problem is a generalization of Burmester’s determination of points in a body that lie on a circle for five planar positions. We focus on seven surfaces that we term “reachable” because they correspond to serial chains with two degree-of-freedom positioning structures combined with a three degree-of-freedom spherical wrist. A homotopy algorithm based on generalized linear products is used to provide a convenient estimate of the number of solutions of these polynomial systems. A parallelized version of this algorithm was then used to numerically determine all of the solutions.
Boundary Condition Design to Heat a Moving Object at Uniform Transient Temperature Using Inverse Formulation
Authors: Ertu¨rk Hakan , Ezekoye Ofodike A. , Howell John R.
Published: September 2004

The boundary condition design of a three-dimensional furnace that heats an object moving along a conveyor belt of an assembly line is considered. A furnace of this type can be used by the manufacturing industry for applications such as industrial baking, curing of paint, annealing or manufacturing through chemical deposition. The object that is to be heated moves along the furnace as it is heated following a specified temperature history. The spatial temperature distribution on the object is kept isothermal through the whole process. The temperature distribution of the heaters of the furnace should be changed as the object moves so that the specified temperature history can be satisfied. The design problem is transient where a series of inverse problems are solved. The process furnace considered is in the shape of a rectangular tunnel where the heaters are located on the top and the design object moves along the bottom. The inverse design approach is used for the solution, which is advantageous over a traditional trial-and-error solution where an iterative solution is required for every position as the object moves. The inverse formulation of the design problem is ill-posed and involves a set of Fredholm equations of the first kind. The use of advanced solvers that are able to regularize the resulting system is essential. These include the conjugate gradient method, the truncated singular value decomposition or Tikhonov regularization, rather than an ordinary solver, like Gauss-Seidel or Gauss elimination.
A Slicing Procedure for 5-Axis LaserAided DMD Process
Authors: Sundaram R. , Choi J.
Published: September 2004

The 5-axis layered manufacturing technology facilitates fabrication of a part with overhanging features without the use of supports, thereby making a direct-to-use part from the layered manufacturing technology a reality. In this paper a direct slicing procedure for a CAD model, a crucial process-planning task for the 5-axis laser aided DMD process is described. The neutral exchange format IGES is used as the slice format. The machine G and M codes for a CNC 5-axis laser aided DMD machine are generated from the slice format and the deposition process is simulated. Implemented examples are included to explain the slicing procedure.
Mechanistic Model of Coaxial Microfiltration for Semi-Synthetic Metalworking Fluid Microemulsions
Authors: Zhao Fu , Urbance Marcy , Skerlos Steven J.
Published: September 2004

This paper discusses the development of a mechanistic model that describes the rate of flow reduction (i.e., flux decline) for a semi-synthetic metalworking fluid (MWF) during the application of microfiltration for extended MWF reuse and recycling. For the transport of unused semi-synthetic MWF through microfiltration membranes ranging in pore size from 0.2 to 5.0 micrometers, Environmental Scanning Electron Microscopy (ESEM) and Confocal Scanning Laser Microscopy (CSLM) are used to identify three interdependent and sequential mechanisms of flux decline: pore constriction, pore blockage, and surface film retardation. These mechanisms are modeled together mathematically as a four-parameter model that quantitatively describes flux decline versus time for semi-synthetic MWF as a function of membrane pore size and transmembrane pressure. The four parameters of the model are the rate constants for pore constriction and pore blocking, the steady-state effective internal pore constriction, and the specific surface film resistance. Independent experimental observations confirmed both the existence of the three stages of flux decline, and the physical interpretation of the model parameters across the pore size range of polycarbonate membranes investigated. It was also found that the mechanistic model fit experimental flux data over time with low error and that the magnitudes and trends of the model parameters closely fit direct microscopic observations and expected behavior of fouled membrane surfaces. Consequently, the mechanistic model enables quantitative modeling of microscopic phenomena at the membrane surface using only macroscale flux observations. This will enable a better understanding of the relationship between MWF formulation and membrane transport in novel MWF recycling applications.
Radiation Thermometry at a High-Speed Turning Process
Authors: Mu¨ller Bernhard , Renz Ulrich , Hoppe Stefan , Klocke Fritz
Published: September 2004

A fiber-optic two-color pyrometer with high spatial and temporal resolution has been applied to measure temperatures at an external turning process. Different measurement positions have been realized at the chip and the workpiece. The measurements have been performed at three different workpiece materials: carbon steel AISI 1045, aluminum alloy AA 7075, and titanium alloy Ti6Al4V. The influences of different parameters like cutting speed, feed, and position of the measurement spot on the temperatures have been investigated. The cutting speed has been increased from conventional values up to 100 m/s for AISI 1045, 117 m/s for AA 7075, and 10 m/s for Ti6Al4V. Additionally, a review of radiation thermometry techniques and applications regarding time resolved temperature measurements in metal cutting will be presented.
A User Interface for Free-Form Shape Design at the Responsive Workbench
Authors: Wesche Gerold
Published: September 2004

This paper presents a virtual environment based user interface for the conceptual design of free form surface models from scratch. The user performs sketching and elaboration directly within a projection-based, table-like environment. He uses head-tracked stereo glasses and simple input devices. We describe user interface components for creation, manipulation, and application control, which were specifically designed for use in a 3D environment. These components are part of a two-handed interaction scheme. In our modeling approach, the user draws curves and constructs a curve network that forms the skeleton of the surface. Automatic surfacing methods generate shapes that correspond to the outlined boundary, thus freeing the designer from specifying all surface parameters by hand. We demonstrate how the use of a virtual environment benefits such creation and manipulation tasks.
Added Stability Lobes in Machining Processes That Exhibit Periodic Time Variation, Part 2: Experimental Validation
Authors: Corpus William T. , Endres William J.
Published: September 2004

Physical experimentation using a kinematically simple straight-edged orthogonal tube-end turning process both verifies the existence of added stability lobes as well as shows good agreement with the analytical solution and numerical simulations of Part 1. The experimental results also verify the added-lobe chatter frequency to be one-half the tooth frequency. Given validation of the analysis and simulation, they are then used to show the effects of variables not easily explored through experimental means, such as overlap factor, multi-tooth cutting, general periodicity and damping. The added-lobes are shown to exist with a zero overlap factor (i.e., no regeneration) and to scale in magnitude (limiting width of cut) relative to overlap factor. Furthermore, the added lobes are shown to exist for multi-tooth machining even when there are no periods of full cutter disengagement (i.e., no free vibration) as well as nonintermittent machining where periodic time variation exists for other reasons, such as spatially dependent stiffness. Finally, it is shown that damping primarily affects the bottom of the added lobes with minimal effect on the higher regions of the boundaries, indicating that structural damping becomes less important at ultrahigh speeds in cases for which the added lobes are the limitation.
Dynamic Electrode Force and Displacement in Resistance Spot Welding of Aluminum
Authors: Ji, C. T. , Zhou, Y.
Published: September 2004

Dynamic electrode displacement and force were characterized during resistance spot welding of aluminum alloy 5182 sheets using a medium-frequency direct-current welder. It was found that both electrode displacement and force increased rapidly at the beginning of the welding stage and then at a reducing rate. Rates of increase in electrode displacement and force were both proportional to welding current. And both electrode displacement and force experienced a sudden drop when weld metal expulsion occurred. However, the rate of increase in electrode displacement did not reach zero during welding even for joints with sufficient nugget diameter, while electrode force peaked when a large nugget diameter was produced. Possible strategies for process monitoring and control were also discussed.
Form Error Evaluation: An Iterative Reweighted Least Squares Algorithm*
Authors: Zhu Xiangyang , Ding Han , Wang Michael Y.
Published: September 2004

This paper establishes the equivalence between the solution to a linear Chebyshev approximation problem and that of a weighted least squares (WLS) problem with the weighting parameters being appropriately defined. On this basis, we present an algorithm for form error evaluation of geometric features. The algorithm is implemented as an iterative procedure. At each iteration, a WLS problem is solved and the weighting parameters are updated. The proposed algorithm is of general-purpose, it can be used to evaluate the exact minimum zone error of various geometric features including flatness, circularity, sphericity, cylindericity and spatial straightness. Numerical examples are presented to show the effectiveness and efficiency of the algorithm.
A New Principle of CNC Tool Path Planning for Three-Axis Sculptured Part Machining—A Steepest-Ascending Tool Path
Authors: Chen Zezhong C. , Vickers Geoffrey W. , Dong Zuomin
Published: September 2004

Three-axis CNC milling is often used to machine sculptured parts. Due to the complex surface shape of these parts, well-planned tool paths can significantly increase the machining efficiency. In this work a new principle of CNC tool path planning for 3-axis sculptured surface machining is proposed. Generic formula to calculate the steepest tangent direction of a sculptured surface is derived, and the algorithm of the steepest-ascending tool path generation is introduced. A single steepest-ascending tool path has been verified to be more efficient than a single tool path of any other type. The relationship between machining efficiency and three key variables, tool feed direction, cutter shape, and surface shape, is revealed. The newly introduced principle is used in planning tool paths of a sculptured surface to demonstrate the advantages of the steepest-ascending tool paths. This new tool path scheme is further integrated into the more advanced steepest-directed and iso-cusped (SDIC) tool path generation technique. Applications of the new tool path principle and the SDIC tool paths to the machining of sculptured parts are demonstrated.
Stream of Variation Modeling and Analysis of Serial-Parallel Multistage Manufacturing Systems
Authors: Huang Qiang , Shi Jianjun
Published: September 2004

In a Serial-Parallel Multistage Manufacturing System (SP-MMS), identical work-stations are utilized at each stage to meet the productivity and line balance requirements. In such a system, parts could go through different process routes and some routes may merge at certain stage(s). Due to the existence of multiple variation streams, it is challenging to model and analyze variation propagation in a system. This paper extends the state space modeling approach from single process route to the SP-MMS with multiple routes. Several model dimension reduction techniques are proposed to reduce model complexity. Properties of these techniques are studied from the perspectives of system representation and diagnosability. Furthermore, these techniques are applied to analyze system measurement strategies.
Character and Behavior of Mist Generated by Application of Cutting Fluid to a Rotating Cylindrical Workpiece, Part 2: Experimental Validation
Authors: Sun J. , Ju C. , Yue Y. , Gunter K. L. , Michalek D. J. , Sutherland J. W.
Published: September 2004

In Part 1 of this paper a model was developed to describe the formation mechanisms and dynamic behavior of cutting fluid mist. This part of the paper focuses on an experimental investigation of the mist generated by the interaction of the fluid with the rotating cylindrical workpiece during a turning operation and the simulation of the dynamic behavior of the mist droplets, resulting in the prediction of the droplet size distribution and the mass concentration within the machining environment. These simulation results are compared to experimental measurements in order to validate the theoretical model presented in Part 1 of the paper. It is observed that the model predictions accurately characterize the observed experimental behavior.