bluuebunny/crossref_metadata_2025 huggingface dataset:
Arthroscopically Assisted Percutaneous Repair of Fresh Closed Achilles Tendon Rupture by Kessler's Suture
Authors: Tang Kang-lai , Thermann Hajo , Dai Gang , Chen Guang-xing , Guo Lin , Yang Liu
Published: December 2006

Background

Achilles tendon ruptures are difficult to repair, and the healing rate is low due to this structure's anatomic and physiological characteristics. It is essential to develop new techniques to increase the healing rate and decrease the rate of complications.

Objective

To propose and evaluate a new percutaneous method of repairing fresh closed Achilles tendon ruptures by Kessler's suture under arthroscopy.

Study Design

Case series; Level of evidence, 4.

Methods

Twenty patients were followed at least 12 months in this study. First, the torn ends of the Achilles tendon were debrided during arthroscopy. Then percutaneous repair of the Achilles tendon was performed using Kessler's suture by an inside-out technique. All cases were followed up for an average range of 21 months (range, 12-36 months). All patients were evaluated by clinical examination, magnetic resonance imaging, and the Lindholm scale.

Results

The torn ends were well aligned and sutured after the debridement under arthroscopy. According to the Lindholm scale, excellent results were seen in 15 cases and good in 5 cases. No patients had complications such as nerve injury, infection, or re-rupture at follow-up. Magnetic resonance imaging results showed that the ruptured Achilles tendons were repaired and remodeled very well in all patients.

Conclusion

The present method is an effective surgical technique for repair of a closed rupture of the Achilles tendon. The short-term follow-up results were good, and recovery time was short. Few complications were found in our study cases.
Dysregulation of the Hypothalamic-Pituitary-Adrenal Axis in Postpartum Depression
Authors: Jolley Sandra N. , Elmore Shawn , Barnard Kathryn E. , Carr Darcy B.
Published: December 2006

Postpartum depression (PPD) affects at least 10% to 15% of postpartum women, including more than 600,000 American mothers in 2003 alone. Dramatic changes in the hypothalamic-pituitary-adrenal (HPA) system in the transition from pregnancy to postpartum coupled with research on the psychobiology of depression provided the foundation for this study. The purpose of this study was to compare the reactivity and regulation of the HPA axis components, adrenocorticotropic hormone (ACTH) and cortisol, in depressed and nondepressed postpartum women. A comparative, longitudinal study design was used with 22 normal, healthy, nondepressed pregnant women. Physiologic and postpartum depression data were collected at 6 and 12 weeks postpartum at a university clinical research center. Maximal treadmill exercise stimulated plasma ACTH and serum cortisol levels which were measured before, during, and after 20 min of exercise. Postpartum depression was measured with the Postpartum Depression Screening Scale. Lag within-subject ACTH levels predicting cortisol regression slopes were significantly different between the depressed and nondepressed groups at both 6 and 12 weeks. The depressed group showed no relationship between their ACTH and cortisol levels, with higher ACTH and lower cortisol levels when compared with the nondepressed group. The expected regulated relationship with cortisol levels rising in response to rising ACTH levels was found in the non-depressed group. These findings indicate that the HPA axis was dysregulated in the depressed group, but regulated in the nondepressed group at 6 and 12 weeks postpartum. This pattern of higher ACTH levels to stimulate less cortisol is similar to patterns found in women with early life stresses.
Effects of High-Intensity Endurance and Resistance Exercise on HIV Metabolic Abnormalities: A Pilot Study
Authors: Robinson F. Patrick , Quinn Lauretta T. , Rimmer James H.
Published: December 2006

The purposes of this pilot study were to examine the effects of a 16-week supervised high-intensity combined endurance and resistance exercise training program on HIV-associated metabolic abnormalities (abdominal adiposity, dyslipidemia, and insulin resistance) and to explore methodological issues related to the design and implementation of the research protocol in preparation for a randomized controlled trial. A one-group pretest-posttest design was used, with outcomes measured at baseline and within 1 week after the conclusion of the training program. The exercise program consisted of 16 weeks (preceded by a 2-week phase-in period) of three endurance sessions (20 min at 70%-80% of VO 2max) and two resistance sessions per week (one set of 8-10 repetitions at 80% of one-repetition maximum on seven exercises). Outcome measures included lipid levels (total, high-density lipoprotein, and low-density lipoprotein cholesterol and triglycerides), visceral and subcutaneous adipose area measured by electron beam tomography, fat and lean mass of trunk and limbs measured by dual-energy X-ray absorptiometry, and insulin sensitivity measured by the homeostatic model assessment. Nine participants were recruited, 5 of whom completed the intervention and had pretest and posttest data available for analyses. Aerobic capacity and strength improved over the course of the intervention. Statistically significant decreases were found for total and trunk fat mass (1,324.9 g [± 733.6] and 992.8 g [± 733.6], respectively). Triglycerides decreased by 59 mg/dL (± 69.88), and insulin sensitivity decreased by 15.7% (± 41.7%), neither of which was a statistically significant change. Results suggest that further testing of the combined exercise intervention in a randomized controlled design is warranted.
A pilot study of the effects of a social-pragmatic intervention on the communication and symbolic play of children with autism
Authors: Keen Deb , Rodger Sylvia , Doussin Kim , Braithwaite Michelle
Published: December 2006

The acquisition of social communication skills is a major challenge faced by children with autism. This pilot study investigated the effects of the Stronger Families Project, a social-pragmatic intervention, on the communication and symbolic abilities of 16 children aged 2–4 years with autism. Standardized measures of the child's communication and symbolic behaviour were conducted by independent observers at a university clinic pre and post-intervention, and parents were interviewed to determine the impact of variables such as maternal stress and competence on the child's social communication. Changes in some communication and symbolic behaviours occurred following the Stronger Families Project intervention according to parent report. However, improvements based on ratings by independent observers were not significant. Results are discussed in relation to the assessment of changes in the social communication and symbolic play of children with autism following intervention using clinical observation and parent report.
Measurement Error in Functional Balance and Mobility Tests for People With Stroke: What Are the Sources of Error and What Is the Best Way to Minimize Error?
Authors: Tyson Sarah F.
Published: December 2006

Objective. To assess the degree and source of measurement error in functional balance and mobility tests for people with stroke, and to identify the most effective method of data collection to minimize error.

Design. To assess the degree and source of error, the total, systematic, and random error were calculated for within-session, test-retest, and interrater testing. To identify the most effective method of data collection, the total error was calculated for 4 data collection methods: 1 familiarization trial, then scoring a 2nd trial; 2 familiarization trials, then scoring a 3rd trial; averaging 2 trials, then averaging 3 trials.

Setting. Stroke services in National Health Service hospitals.

Patients. Thirty-five people with a poststroke hemiplegia.

Interventions. None.

Main Outcome Measures. Five tests provided interval-level data: arm raise (sitting and standing), weight shift, tap, and step-up. Four tests provided ratio-level data: forward reach (sitting and standing) and 5-m timed walk (with and without an aid).

Results. Total measurement error ranged from zero for the step-up test to 55% for within-session error for the 5-m walk without an aid. Ratio data tests showed somewhat greater error than interval data tests (5%-55% vs. 0%-46%). A within-session practice effect for the standing forward reach, 5-m walk (with and without an aid), and weight shift tests was found. For the other tests, random error was greater than the systematic error. Interrater testing had the least error. For most tests, the average of 2 trials produced the least measurement error. For the 5-m walk, the mean obtained from 2 or 3 trials was equally effective. For the step-up test, the mean of 3 trials was slightly more effective. The overall error from all 3 sources was 3 lifts for sitting arm raise, 11 cm for sitting forward reach, 3 lifts for the standing arm raise, 7.5 cm for standing forward reach, 4.5 s for walking with an aid, 3 shifts on the weight shift test, 1.1 s for walking without an aid, 2 taps, and 1 step up.

Conclusion. The tests using interval data showed less error than ratio-data tests and may be preferable measurement tools. Taking an average of 2 trials was the most accurate data collection method.
Effects of a Rostral Motor Cortex Lesion on Primary Motor Cortex Hand Representation Topography in Primates
Authors: Friel Kathleen M. , Barbay Scott , Frost Shawn B. , Plautz Erik J. , Stowe Ann M. , Dancause Numa , Zoubina Elena V. , Nudo Randolph J.
Published: December 2006

Background. Small lesions to rostral versus caudal portions of the hand representation in the primary motor cortex (M1) produce different behavioral deficits. The goal of the present study was to determine if rehabilitative training has similar effects on functional topography of the spared M1 after rostral versus previously reported caudal M1 lesions.

Methods. Following a lesion to the rostral M1 hand area, monkeys were trained for 1 h/day for 30 days to retrieve food pellets from small wells using their impaired hand. Electrophysiological maps of the M1 were derived in anesthetized monkeys before infarct and after rehabilitative training using intracortical microstimulation.

Results. After a lesion to the rostral M1 and rehabilitative training, the size of the spared hand representation decreased 1.2%. This change is not statistically different from the 9% increase seen after caudal M1 lesion and rehabilitative training ( P > 0.2).

Conclusion. Postlesion training spares peri-infarct hand area regardless of whether the lesion is in the rostral or caudal M1.
Selective extraction of the amorphous Al, Fe and Si oxides using an alkaline Tiron solution
Authors: Biermans V. , Baert L.
Published: December 2006

A selective chemical dissolution method has been worked out in order to characterize quantitatively amorphous Al, Fe and Si oxides simultaneously in soils. Based on theoretical considerations an alkaline Tiron solution was tried out. Experiments on well-characterized synthetic and natural substrates were carried out in order to find the optimum set of conditions of pH, temperature and reaction time. These are: an alkaline medium consisting of 0·1 m Tiron and buffered at pH 10·5, an extraction temperature of 80°C and an extraction time of 1 h.
Petrographic and isotopic studies of the altered acid volcanics of the Tolfa-Cerite area, Italy: the genesis of the clays
Authors: Lombardi G. , Sheppard S. M. F.
Published: December 2006

Alunite-kaolinite deposits occur in argillized zones in acid volcanic rocks at Tolfa. Over seventy samples were examined by one or more of the following methods: thin section, DTA, X-ray, IR, TG, SEM, chemical, and hydrogen and oxygen isotope analysis. Kaolinite and dickite, of high structural order, are the dominant clays with micamontmorillonite and halloysite subordinate. In many samples kaolinite and dickite coexist; their relative amounts are variable but the dickite content tends to increase with depth. SEM studies show that dickite crystals—up to 30 µm—are bigger than kaolinite.

The D/H and18O/16O ratios of six clays, a whole rock, two biotites from fresh host rock, two chalcedony veins and three local meteoric waters indicate that the clays formed in a meteoric-hydrothermal environment of acid hot spring type at about 80°C. The fresh volcanic host rocks are strongly enriched in18O relative to ‘normal’ igneous rocks due to derivation from or exchange with18O-rich sedimentary rocks at depth prior to hydrothermal and solfataric activity. In the absence of present-day geothermal activity the life of this hot spring system was less than 4 m.y.
Fine structure in the selected area diffraction patterns of beidellite, and its dark-field images
Authors: Güven N. , Pease R. W. , Murr L. E.
Published: December 2006

Commonly streaks and rarely extra spots are observed on the selected area diffraction patterns of beidellite. The streaks are non-radial, and are restricted along the direction parallel to [11], [11], and [01]. Extra spots appear instead of streaks between the normal Bragg spots along the direction parallel to [11] and [11]. These extra spots suggest the formation of a superlattice with the a and b cell parameters twice as large as those of the beidellite lattice. Dark-field images on the strong 020 reflection reveal the presence of a network of dislocations in some of the beidellite crystallites. These dislocations suggest that the chemistry is not uniform over the successive layers in these crystallites. The structural difference between the layers seems to be accommodated by the dislocations.
Density and structure of allophane
Authors: Wada Shin-Ichiro , Wada Koji
Published: December 2006

The densities of two allophane samples measured by displacement with water were 2·72–2·78 g/cm3, while those measured by a float-sink test in CH3OH-, CH3 COCH3-, C6H6- and CCl4-C2H2Br4 mixtures were 1·84, 1·94–1·98, 2·35 and 2·35–2·39 g/cm3, respectively. The results of the density determinations for montmorillonite, kaolinite, halloysite, imogolite and volcanic glass are also reported. The data were interpreted in terms of the accessibility of the displacement liquids to void spaces within and between the layers or ‘structure units’ of the minerals and a model of the ‘structure units’ of allophane is proposed.
Archerite, (K,NH4)H2PO4, a new mineral from Madura, Western Australia
Authors: Bridge P. J.
Published: December 2006

Archerite, (K, NH4)H2PO4, a new mineral, has been found in Petrogale Cave, 36 km east of Madura Motel (31° 54′S, 127°00′E) Western Australia. Archerite and biphosphammite together with aphthitalite, halite, syngenite, stercorite, oxammite, weddellite, whitlockite, guanine, newberyite, calcite, (NH4)2Ca(HPO4)2·H2O, and an unknown occur as stalactites and wall and floor crusts.

Archerite is tetragonal with second order prisms and pyramids in crystals up to 2 mm in length with D 2·23, ω 1·513, ε 1·470, all close to artificial KH2PO4. The mineral is soft, has a white streak, and is soluble in cold H2O. Cell dimensions of natural archerite were not determined and the composition was calculated from measurements of selected powder lines correlated with charts prepared from end-member data and by chemistry which gave 81% KH2PO4 and K2O 10·8, NH2 3·46 respectively, the latter corresponding to (K0·74(NH4)0·26)H2PO4.

The name is for Dr. M. Archer, Curator of Mammals, Queensland Museum. Type material is stored in the collections of the Government Chemical Laboratories, Perth, Western Australia.
Review of the hydrated oxides of U and Pb, with new X-Ray powder data
Authors: Deliens Michel
Published: December 2006

New X-ray powderdata are presented for vandendriesscheite, fourmarierite, masuyite, and wölsendorfite. Literature data on the known U-Pb hydrated oxides is reviewed, and suitable criteria for their distinction are set forth.
Westerveldite from Igdlúnguaq, Ilímaussaq alkaline massif, South Greenland
Authors: Oen I. S. , Burke E. A. J. , Kieft C.
Published: December 2006

Microprobe and X-ray investigation of a mineral occurring with breithauptite, nickeline, and other arsenides in the naujaite at Igdlúnguaq, Ilímaussaq alkaline massif, S. Greenland, shows that this mineral, which was formerly misidentified as ‘maucherite’, is a westerveldite (Fe0·85Ni0·15)As, of much iron-richer composition than the nickeloan westerveldites from the only two other known occurrences of this mineral. Westerveldite from Igdlúnguaq was presumably formed by reaction of nickeline with iron-rich solutions under conditions of reheating at temperatures of about 450° C and under partial pressures of arsenic below those necessary to stabilize nickeline. Sulphur-bearing löllingite occurs as exsolution blades in the westerveldite. Iron-rich nickeline, up to a composition (Ni0·82Fe0·18)As0·95Sb0·05, was presumably formed by recrystallization of nickeline in the transition stage just before this mineral became unstable and was replaced by westerveldite.
Geochemistry and strontium isotopic composition of basalts from the Eastern Deccan volcanic province, India
Authors: Alexander P. Oliver , Paul Dalim K.
Published: December 2006

Ten rather uniform tholeiitic basalt flows totalling a thickness of 190 m from Sagar, India, contain two stratigraphical breaks. Major element variation allows the flows to be grouped into two eruption cycles. Due to intraflow variation, however, chemical composition is unlikely to be useful in widespread correlation of flow sequence. The initial 87Sr/86Sr ratios vary from 0·7039 to 0·7084 with Rb and Sr averaging 6·5 and 184 ppm respectively and Rb/Sr ratios ranging from 0·002 to 0·224, with no systematic relationship between the initial 87Sr/86Sr ratios and other chemical parameters. Bulk crustal contamination is considered unlikely; selective introduction of 87Sr from the granitic basement is postulated.
Petrological aspects of the correlation between potash content of orogenic magmas and earthquake depth
Authors: Cawthorn R. Grant
Published: December 2006

The petrological interpretation of the variation of K2O content with depth to the Benioff zone in orogenic magmas is complicated by several factors: (1) Magmas may not be true primary liquids but have under-gone differentiation. K2O contents, at a specific SiO2level, will depend upon the SiO2content of the parental magma and the natureof the crystallizing phases more than on original K2O content. (2) The depth to the Benioff zone may not give a true reflection of the depth of melting. Magmas may not be derived from the uppermost layer of subducted oceanic crust but rather the overlying upper mantle. Earthquakes may not occur in the uppermost layer of the subducted plate, but in its colder, central parts. Hence, earthquake depth may not be related to the source of the magma. (3) It is difficult to envisage how the temporal increase in K2O may occur in certain areas (e.g.Aleutian I., Fiji) if it is primarily controlled by the depth to the Benioff zone.

There may be some correlation between K2O content of magmas and earthquake depth, but its cause is difficult to determine. None of the existing explanations is entirely satisfactory, and it is suggested that varying degrees of fractional crystallization may play an important role in controlling K2O contents.
The geochemistry of basalt-sea-water interactions: evidence from Deception Island, Antarctica, and Reykjanes, Iceland
Authors: Elderfield H. , Gunnlaugsson E. , Wakefield S. J. , Williams P. T.
Published: December 2006

Sea-water from Deception Island was found to contain 0·55–1·48 mg Mn 1−1 and 10·2-64·3 mg Si 1−1. Reaction of Deception Island basalt and sea-water at 190 °C and 500 bars simulated the measured water composition but leaching experiments suggest that much of the Mn etc. may derive from local volcanic ash. Mn and Mg in thermal waters at Reykjanes have concentrations compatible with equilibrium with components of montmorillonite present as an alteration mineral of average composition . However, Fe is controlled by equilibrium with sulphides. Flux calculations based on these and other data place upper limits on hydrothermal Mn input to the oceans of 5–36×1011 g yr−1 and Mn accumulation in metalliferous sediments of 2–9×1011 g yr−1.
Geothermometry and oxygen barometry using coexisting iron-titanium oxides: a reappraisal
Authors: Powell Roger , Powell Marjorie
Published: December 2006

Equilibrium thermodynamic methods are used to develop an independent iron-titanium oxide geothermometer and oxygen barometer from the experimental data of Buddington and Lindsley (1964). The geothermometer and oxygen barometer are presented graphically for coexisting ilmenite solid solution and magnetite solid solution in the system FeO-Fe2O3-TiO2. Equations are also given for calculating temperature and oxygen activity for natural coexisting iron-titanium oxides containing other components. Large departures in composition from the system FeO-Fe2O3-TiO3 result in large uncertainties in the calculated temperature and activity of oxygen.
The crystal structure of ferrinatrite, Na3(H2O)3[Fe(SO4)3] and its relationship to Maus's salt, (H3O)2K2{K0.5(H2O)0.5}6[Fe3O(H2O)3(SO46](OH)2
Authors: Scordari F.
Published: December 2006

Ferrinatrite crystallizes in space group P, with a = 15·566(5), c = 8·69(1) Å, and Z = 6. The crystal structure was solved by three-dimensional Patterson and Fourier syntheses, and refined by least squares employing 2378 independent reflexions to a final R value of 0·068. The iron ions occupy special positions and are surrounded octahedrally by oxygen atoms. Fe3+O6 octahedra and SO4, tetrahedra are linked together to form infinite chains of Fe-O-S linkages in the [0001] direction. These chains are linked to each other by [NaO5(H2O)2] polyhedra and probably by hydrogen bonds. The topology of the arrangement is the same as that of the hypothetical P312 structure proposed by Moore and Araki (1974).
Unusual sulphide replacement textures in altered olivine-rich rocks of the Bulong Complex near Kalgoorlie, Western Australia
Authors: Moeskops P. G. , Davis G. R.
Published: December 2006

Unusual replacement-type sulphide mineralization occurs in the northern part of the Bulong Complex, about 30 km east of Kalgoorlie, Western Australia. The mineralization is non-economic (up to 0·5% Ni, 0·4% Cu, 0·1% Co, and 8·6% S) and occurs in altered unlayered olivine-rich rocks immediately above a thin sheet-like inclusion of country rock. The supergene-modified primary opaque assemblage pyrrhotine-magnetite-pyrite-chalcopyrite-(pentlandite) is texturally unusual in that the opaques are largely pseudomorphic after primary olivine grains, mainly within irregular fracture networks in a manner similar to ‘early’ serpentine. Textural relations between opaques and silicates indicate that the mineralization was introduced during the early stages of serpentinization prior to the onset of deformation and regional metamorphism. Monoclinic pyrrhotine is the main opaque phase, with some grains containing relict cores of the hexagonal variety. Magnetite associated with the mineralization is Ni-poor (< 0·1% Ni) compared with ‘serpentinization magnetite’ from elsewhere in the Bulong Complex, which contains 0·5–0·8% Ni. As the mineralization was intersected at relatively shallow depth, supergene alteration effects are evident; pyrrhotine is locally altered to pyrite and marcasite (texturally and chemically distinct from the primary pyrite), and pentlandite is largely replaced by cupriferous violarite.

Textural features and consideration of phase relations in the system Cu-Fe-S-O suggest that the mineralization is of low-temperature (350± °C) hydrothermal origin. By contrast, the more commonly developed Fe-Ni-Cu sulphide mineralization of the Kalgoorlie region is generally considered to be of high-temperature (1200± °C) magmatic origin.
A celadonite-vermiculite series from the volcanic rocks of the Ochils, Stirlingshire
Authors: French W. J. , Hassan M. D. , Westcott J. E.
Published: December 2006

Spherulitic and felted green to brown minerals are described from various volcanic rocks of the Western Ochils, Stirlingshire. They fill amygdales and replace pyroxenes and appear to be an interlayered series of sheet silicates from celadonite to vermiculite. The minerals are hydrothermal in origin and suggest the presence of a potassium-rich hydrous fluid at a late stage in the volcanic history.
Janggunite, a new manganese hydroxide mineral from the Janggun mine, Bonghwa, Korea
Authors: Kim Soo Jin
Published: December 2006

Janggunite occurs as radiating groups of flakes, flower-like aggregates, colloform bands, dendritic or arborescenl masses in the cementation zone of the supergene manganese oxide deposits. The flakes average 0·05 mm. Colour black, lustre dull, streak brownish black to dark brown. Cleavage one direction perfect. H = 23, very fragile.Dmeas= 3·59,Dcalc= 3·58. Under reflected light anisotropic and bireflectant. No internal reflections. Etching reactions: positive - HC1, HNO3, SnCl2, H2O2, H2SO4+ H2O2. Chemical formula,on the basis of O = 14, or ideally. The mineral has an orthorhombic unit cell witha9·324,b14·05,c7·956 Å, Z = 4,a:b:c= 0·663:1:0·566. Important diffraction lines are 9·34(s), 7·09(s), 4·62(m), 4·17(m), 3·547(s), 3·101(s), 2·597(w), 2·469(m), 1·863(w), 1·664(w), 1·525(m), 1·405(m), D.T.A. curve shows the endothermic peaks at 250–370°C and 955°C Infra-red absorption spectral curve shows vibrations at 515 cm−1, 545 cm−1, 1025 cm−1, and 3225 cm−1. The mineral and name have been approved before publication by the Commission on New Minerals and Mineral Names, I.M.A.
The Pten/PI3K pathway governs the homeostasis of Vα14iNKT cells
Authors: Kishimoto Hiroyuki , Ohteki Toshiaki , Yajima Nobuyuki , Kawahara Koichi , Natsui Miyuki , Kawarasaki Satoru , Hamada Koichi , Horie Yasuo , Kubo Yoshiaki , Arase Seiji , Taniguchi Masaru , Vanhaesebroeck Bart , Mak Tak Wah , Nakano Toru , Koyasu Shigeo , Sasaki Takehiko , Suzuki Akira
Published: December 2006

The tumor suppressor PTEN is mutated in many human cancers. We previously used the Cre-loxP system to generate mice (LckCrePten mice) with a Pten mutation in T-lineage cells. Here we describe the phenotype of Pten-deficient Vα14iNKT cells. A failure in the development of Vα14iNKT cells occurs in the LckCrePten thymus between stage 2 (CD44highNK1.1−) and stage 3 (CD44highNK1.1+), resulting in decreased numbers of peripheral Vα14iNKT cells. In vitro, Pten-deficient Vα14iNKT cells show reduced proliferation and cytokine secretion in response to αGalCer stimulation but enhanced inhibitory Ly49 receptor expression. Following interaction with dendritic cells (DCs) loaded with αGalCer, Pten-deficient Vα14iNKT cells demonstrate activation of PI3K. Indeed, the effects of the Pten mutation require intact function of the PI3K subunits p110γ and p110δ. In vivo, LckCrePten mice display reduced serum IFNγ after αGalCer administration. Importantly, Vα14iNKT cell–mediated protection against the metastasis of melanoma cells to the lung was impaired in the absence of Pten. Thus, the Pten/PI3K pathway is indispensable for the homeostasis and antitumor surveillance function of Vα14iNKT cells.
TLR agonists induce regulatory dendritic cells to recruit Th1 cells via preferential IP-10 secretion and inhibit Th1 proliferation
Authors: Qian Cheng , An Huazhang , Yu Yizhi , Liu Shuxun , Cao Xuetao
Published: December 2006

Dendritic cells (DCs) and chemokines are important mediators linking innate and adaptive immunity on activation by Toll-like receptor (TLR) agonists. We previously identified a kind of regulatory DC subset (diffDCs) that differentiated from mature DCs under splenic stroma and that inhibited T-cell proliferation. The responsiveness of such regulatory DCs to TLR agonists and their pattern of chemokine production remain to be determined. Here, we report that the regulatory DCs secrete a higher level of CXCR3 chemokine IFN-γ–induced protein-10 (IP-10) than immature DCs (imDCs), and more IP-10 is produced after stimulation with TLR-2, -4, -3, and -9 ligands. Blockade of IFN-α/β inhibits IP-10 production by TLR agonist-activated regulatory DCs. We show that the increased IRF-3 and IFN-β–induced STAT1 activation are responsible for the autocrine IFN-β–dependent preferential production of IP-10 by regulatory DCs. In addition, stimulation with recombinant mouse IFN-α/β induces more IP-10 production in regulatory DCs than that in imDCs. Moreover, the regulatory DCs selectively recruit more Th1 cells through IP-10 and inhibit Th1 proliferation. Our results demonstrate a new manner for regulatory DCs to down-regulate T-cell response by preferential IP-10 production and inhibition of recruited Th1 cell proliferation.
Consequences of over-expression of rat Scavenger Receptor, SR-BI, in an adrenal cell model
Authors: Reaven Eve , Nomoto Ann , Cortez Yuan , Azhar Salman
Published: December 2006

Background

The plasma membrane scavenger receptor, SR-BI, mediates the 'selective uptake' process by which cholesteryl esters (CE) from exogenously supplied HDL are taken up by target cells. Recent work suggests that dimer and higher order oligomeric forms of the SR-BI protein are important to this process. SR-BI has been shown to be particularly associated with microvilli and microvillar channels found at the cell surface of steroidogenic cells, and a study with the hormone stimulated adrenal gland has shown impressive changes in the size and complexity of the microvillar compartment as the mass of CE uptake (and accompanying steroidogenesis) fluctuates. In the present study, we examine a cell line in which we overexpress the SR-BI protein to determine if morphological, biochemical and functional events associated with SR-BI in a controlled cell system are similar to those observed in the intact mammalian adrenal which is responsive to systemic factors.

Methods

Y1-BS1 mouse adrenocortical cells were transiently transfected using rat SR-BI-pcDNA6-V5-His, rat SR-BI-pcDNA6-cMyc-His or control pcDNA6-V5-His vector construct using a CaPO4 precipitation technique. Twenty four hours after transfection, cells were treated with, or without, Bt2cAMP, and SR-BI expression, CE uptake, and steroidogenesis was measured. SR-BI dimerization and cell surface architectural changes were assessed using immunoelectron microscopic techniques.

Results

Overexpression of the scavenger receptor protein, SR-BI, in Y1-BS1 cells results in major alterations in cell surface architecture designed to increase uptake of HDL supplied-CEs. Changes include [1] the formation of crater-like erosions of the surface with multiple double membraned channel structures lining the craters, and [2] dimerized formations of SR-BI lining the newly formed craters and associated double membraned channels.

Conclusion

These data show that overexpression of the scavenger receptor protein, SR-BI (accompanied by suitable hormone treatment and lipoproteins) in susceptible mammalian cells – is associated with increased cholesterol uptake and SR-BI dimerization within a much enlarged and architecturally complex microvillar compartment. These changes duplicate the structural, biochemical and functional changes related to the uptake of HDL CEs normally signaled by the action of ACTH on intact adrenal tissue.
Eg5 steps it up!
Authors: Valentine Megan T , Fordyce Polly M , Block Steven M
Published: December 2006

Understanding how molecular motors generate force and move microtubules in mitosis is essential to understanding the physical mechanism of cell division. Recent measurements have shown that one mitotic kinesin superfamily member, Eg5, is mechanically processive and capable of crosslinking and sliding microtubules in vitro. In this review, we highlight recent work that explores how Eg5 functions under load, with an emphasis on the nanomechanical properties of single enzymes.
Gelsolin: A Novel Thyroid Hormone Receptor-β Interacting Protein that Modulates Tumor Progression in a Mouse Model of Follicular Thyroid Cancer
Authors: Kim Caroline S. , Furuya Fumihiko , Ying Hao , Kato Yasuhito , Hanover John A. , Cheng Sheue-yann
Published: December 2006

Follicular thyroid cancer (FTC) is known to metastasize to distant sites via hematogenous spread; however, the underlying pathways that contribute to metastasis remain unknown. Recent creation of a knockin mutant mouse that expresses a mutant thyroid hormone receptor-β (TRβPV/PV mouse) that spontaneously develops thyroid cancer with metastasis similar to humans has provided new opportunities to study contributors to FTC metastasis. This study evaluates the role of gelsolin, an actin-regulatory protein, in modulating the metastatic potential of FTC. Gelsolin was previously found by cDNA microarray analysis to be down-regulated in TRβPV/PV mice as compared with wild-type mice. This study found an age-dependent reduction of gelsolin protein abundance in TRβPV/PV mice as tumorigenesis progressed. Knockdown of gelsolin by small interfering RNA resulted in increased tumor cell motility and increased gelsolin expression by histone deacetylase inhibitor (trichostatin A) led to decreased cell motility. Additional biochemical analyses demonstrated that gelsolin physically interacted with TRβ1 or PV in vivo and in vitro. The interaction regions were mapped to the C terminus of gelsolin and the DNA binding domain of TR. The physical interaction of gelsolin with PV reduced its binding to actin, leading to disarrayed cytoskeletal architectures. These results suggest that PV-induced alteration of the actin/gelsolin cytoskeleton contributes to increased cell motility. Thus, the present study uncovered a novel PV-mediated oncogenic pathway that could contribute to the local tumor progression and metastatic potential of thyroid carcinogenesis.
Oxytocin Receptors Differentially Signal via Gq and Gi Proteins in Pregnant and Nonpregnant Rat Uterine Myocytes: Implications for Myometrial Contractility
Authors: Zhou Xiao-Bo , Lutz Susanne , Steffens Frank , Korth Michael , Wieland Thomas
Published: December 2006

Oxytocin (OT) receptors are important regulators of myometrial contractility. By using the activity of large conductance Ca2+-activated K+ (BKCa) channels as readout, we analyzed OT signaling in cells from nonpregnant (NPM) and pregnant (PM) rat myometrium in detail. In nystatin-perforated whole-cell patches from NPM cells, which leave the intracellular integrity intact, OT transiently increased BKCa-mediated outward currents (Iout). This OT-evoked Iout was caused by the Ca2+ transients in response to the Gq/11-mediated activation of phospholipase C and was inhibited by activation of protein kinase A (PKA). In an open-access whole-cell patch (OAP), the OT-induced transient rise in Iout was disrupted whereas the regulation of BKCa by the cAMP/PKA cascade remained intact. OT counteracted the isoprenaline, i.e. the β-adrenoceptor/Gs-mediated effect in NPM cells measured in OAP. In contrast, OT further enhanced the β-adrenoceptor/Gs-mediated effect on BKCa activity in PM cells. All OT effects in the OAP were mediated by pertussis toxin-sensitive Gi proteins and PKA. By quantitative real-time PCR and overexpression of the recombinant protein, we demonstrate that an up-regulation of the Gβγ-stimulated adenylyl cyclase II during pregnancy is most likely responsible for this switch. By studying the OT-evoked Iout in nystatin-perforated whole-cell patches of PM cells, we further detected that the OT receptor/Giβγ-mediated coactivation of adenylyl cyclase II enhanced the β-adrenoceptor/Gs-induced suppression of the OT-evoked Ca2+ transients and thus diminishes and self-limits OT-induced contractility. The differential regulation of the PKA-mediated suppression of OT-evoked Ca2+ transients and BKCa activity likely supports uterine quiescence during pregnancy.
Scenario-based comparison and evaluation: Issues of current business process modelling languages
Authors: Xinming Jin , Haikun Wei
Published: December 2006

Business process modelling (BPM) is an important way to understand business processes and provides a basis for further improvement and integration. In this paper, five business process modelling languages are used to model a business scenario and their advantages and disadvantages are discussed. Some process characteristics are derived from real scenarios and used for evaluating current business process modelling languages. The evaluation results reveal that none of the business process modelling languages studied can fulfil the modelling requirements. The limitations of current business process modelling languages are further investigated and future research directions are discussed.
Optimal production lot sizing with backlogging, random defective rate, and rework derived without derivatives
Authors: Chiu Yuan-Shyi Peter , Lin Hong-Dar , Cheng Feng-Tsung
Published: December 2006

This paper is concerned with the algebraic derivation for the production lot size problem with backlogging, random defective rate, and rework. Conventional approaches for solving optimal production lot size are by using the differential calculus on the productioninventory cost function with the need to prove optimality first. Recent articles proposed the algebraic approach to the solution of the classic economic order quantity (EOQ) and economic production quantity (EPQ) models without reference to the use of derivatives. This paper extends it to an EPQ model taking backlogging, random defective rate, and rework into consideration. This note demonstrates that optimal lot size for such an imperfect quality EPQ model can be derived without derivatives. The expected production-inventory costs can also be obtained immediately.
Disassembly scheduling with capacity constraints: Minimizing the number of products disassembled
Authors: Kim Jun-Gyu , Jeon Hyong-Bae , Kim Hwa-Joong , Lee Dong-Ho , Xirouchakis Paul
Published: December 2006

Disassembly scheduling, one of the important operational problems in disassembly systems, is the problem of determining the timing and quantity of disassembling used or end-of-life products to satisfy the demand of their parts or components over a given planning horizon. This paper focuses on the case of single product type without parts commonality while the resource capacity restrictions are considered explicitly. The problem is formulated as an integer programming model with the objective of minimizing the number of products disassembled, and a solution algorithm is suggested after deriving its optimal solution properties. Computational experiments are done on various test problems, and the results show that the algorithm suggested in this paper gives optimal solutions for the test problems within a very short amount of computation time.
A computer vision-based fast approach to drilling tool condition monitoring
Authors: Atli A Volkan , Urhan O , Ertürk S , Sönmez M
Published: December 2006

A computer vision-based approach to drilling tool condition monitoring is proposed in this paper. Firstly, image frames are captured using a high-speed CCD camera. Then, a Canny edge detector is employed to extract tool features from the acquired images. In order to obtain a measure of tool wear, the deviation from linearity (DEFROL) metric is proposed. Experimental results show that the proposed method detects the condition of all tested tools successfully.
Ant colony optimization to select the best process plan in an automated manufacturing environment
Authors: Tiwari M K , Dashora Y , Kumar S , Shankar R
Published: December 2006

In the present dynamic manufacturing systems, optimal process plan selection is quite an intricate task. Systematic determination of processing steps for the transformation of raw material to finished products is known as process planning. The complexity of process plan selection increases with the availability of alternative machines, alternative set-ups, and alternative processes for manufacturing the same part types. The ant colony optimization (ACO) algorithms are multiagent systems in which the behaviour of each ant is inspired by the foraging behaviour of real ants to solve the optimization problem. This paper presents yet another successful application of ACO to solve real-world problems by resolving the complex process plan selection (PPS) problem. The primary advantage of using ACO is that it stabilizes the solution with considerably less computational effort and time without any deterioration in the quality. The proposed strategy has been applied over a few benchmark problems from the literature, and the results establish the competitive advantage of ACO over the established strategies. Comparative analysis of the proposed strategy with other well-established methodologies confirms its effectiveness and superiority.
Forming properties of four high-strength sheet steels
Authors: Rees D W A
Published: December 2006

The tensile behaviours of four sheet steels reveal that their strength, ductility, and anisotropy vary with direction in the plane of the sheet. The flow curves in each of three carbon steels (DP600, DP450, and GA220) are represented with Hollomon's law, in which slight differences in strength coefficient and hardening exponent reflect a direction dependence. The ductilities of the carbon steels (20–30 per cent elongation) contrast with the greater amount (50 per cent) found for 18–8 stainless steel, the flow curve of which more closely followed Ludwik's law. The contrasting formabilities of the four steels are revealed within n and r values found parallel and transverse to the roll. Contrary to expectation, the r values for each of these forming steels do not increase much above unity. Indeed, the majority of r values found were slightly less than unity, when based upon natural plastic strains. A common source of error in the r value is also examined. The correct r measurement should be based upon plastic strain and not total strain. This requires a subtraction of the elastic component of strain from the total strain, either by using the elastic modulus or, as was used here, by a repeated load-unload test procedure. The failure to remove elastic strain in a low region of total strain, where elastic and plastic components are of comparable magnitudes, can mislead, as when r values are found from a non-linear, total strain plot. Although the error from this source is diminished in a higher region of total strain, where its plastic component is dominant, the non-linear total strain plot cannot determine the r value precisely. Plastic strain plots for the three carbon steels are found to be sensibly linear throughout their uniform strain range. This allows an association to be made between a single, true r value and a given in-plane direction. A graphical compensation for correcting the error arising in r value determination, when not omitting elastic strain, is given for each material.
Cost estimation for rapid manufacturing - laser sintering production for low to medium volumes
Authors: Ruffo M , Tuck C , Hague R
Published: December 2006

Rapid manufacturing (RM) is a modern production method based on layer by layer manufacturing directly from a three-dimensional computer-aided design model. The lack of tooling makes RM economically suitable for low and medium production volumes. A comparison with traditional manufacturing processes is important; in particular, cost comparison. Cost is usually the key point for decision making, with break-even points for different manufacturing technologies being the dominant information for decision makers. Cost models used for traditional production methodologies focus on material and labour costs, while modern automated manufacturing processes need cost models that are able to consider the high impact of investments and overheads. Previous work on laser sintering costing was developed in 2003. This current work presents advances and discussions on the limits of the previous work through direct comparison. A new cost model for laser sintering is then proposed. The model leads to graph profiles that are typical for layer-manufacturing processes. The evolution of cost models and the indirect cost significance in modern costing representation is shown finally.
Modelling and simulation of freeform surface generation in ultra-precision raster milling
Authors: Cheung C F , Kong L B , Lee W B , To S
Published: December 2006

Optical freeform surfaces are large-scale surface topologies with shapes generally possessing non-rotational symmetry with submicrometric form accuracy and nanometric surface finish. Due to the geometrical complexities, the prediction of form accuracy in ultraprecision raster milling of ultra-precision freeform surfaces is more difficult than conventional machining. Nowadays, the achievement of submicrometre form accuracy still depends largely on the experience and skills of the machine operators through an expensive trial-and-error approach. This paper presents a model-based simulation system for the prediction of form accuracy in ultra-precision raster milling of optical freeform surfaces. The system takes into account the cutting mechanics, cutting strategy, and the kinematics of the cutting process. Experimental work has been undertaken to verify the system and the predicted results agree well with the experimental results. The successful development of the model-based simulation system allows the optimum cutting parameters and cutting strategies to be determined without the need to conduct massive and costly trial-and-error cutting tests.
Evaluating errors in screw rotor machining by tool to rotor transformation
Authors: Stosic N
Published: December 2006

Screw compressor rotors are machined mainly by form grinding or milling tools. The precision requirements imposed upon them are today so demanding that the tool is allowed only limited wear and must be well set in the machine. It is therefore important to be able to quantify the tool set errors as well as to compensate for tool deformation and wear. Tool to rotor transformation is applied here to quantify these properties. Three possible errors are analysed, namely mismatch of the angle between the tool and rotor shafts, mismatch of the centre distance between the tool and the rotor, and mismatch in the axial tool position. The effect of tool deformation on the accuracy of the rotor is also considered. The effect of all three set errors is then used to compensate for the tool wear. A similar technique is valid for many machining processes in which form tools are used.
Hough transform and thermo-vision for monitoring pantograph-catenary system
Authors: Landi A , Menconi L , Sani L
Published: December 2006

The pantograph-overhead contact wire system is investigated by using an infrared camera. As the pantograph has a vertical motion because of the non-uniform elasticity of the catenary, in order to detect the temperature along the strip from a sequence of infrared images, a segment-tracking algorithm, based on the Hough transformation, has been employed. An analysis of the stored images could help maintenance operations revealing, for example, overheating of the pantograph strip, bursts of arcing, or an irregular positioning of the contact line. Obtained results are relevant for monitoring the status of the quality transmission of the current and for a predictive maintenance of the pantograph and of the catenary system. Examples of analysis from experimental data are reported in the paper.
Weld defect formation in rail thermite welds
Authors: Chen Y , Lawrence F V , Barkan C P L , Dantzig J A
Published: December 2006

A previously developed heat transfer model is used to study the influence of welding parameters on weld defect development in thermite welds. Weld defect formation maps are constructed from a series of heat transfer simulations. For the current normal rail thermite welding conditions, it is found that shrinkage cavity formation can be avoided but cold-lap and centre-line defects are likely to occur. This study also shows that increasing the preheating time or the liquid temperature can suppress the development of cold-lap and centre-line defects but can lead to a slightly higher microporosity content in the railhead as well. Alternatively, it is found that instead of increasing the preheating time or the liquid temperature, the same effect can be achieved by increasing the 25 mm weld gap (standard) to a slightly larger value.