Lower Flank Research Articles

Systemic Antitumor Effect of Intratumoral Injection of Dendritic Cells in Combination with Local Photodynamic Therapy

Photodynamic therapy (PDT), which is used clinically for the palliative treatment of cancer, induces local tumor cell death but has no effect on tumors in untreated sites. The purpose of this study was to determine if local PDT followed by intratumoral injection of naïve dendritic cells (IT-DC) induces systemic antitumor immunity that can inhibit the growth of untreated as well as PDT + IT-DC-treated tumors. BALB/c or C57Bl/6 mice were injected s.c. with CT26 colorectal carcinoma cells and B16 melanoma cells, respectively, and following 10 to 12 days of tumor growth, the tumors were treated with PDT alone or PDT followed by IT-DC or IT-PBS. In other studies, tumors were established simultaneously in both lower flanks or in one flank and in the lungs, but only one flank was treated. Whereas neither PDT nor IT-DC alone was effective, PDT + IT-DC eradicated both CT26 and B16 tumors in a significant proportion of animals and prolonged the survival of mice of which the tumors were not cured. The spleens of mice treated with PDT + IT-DC contained tumor-specific cytotoxic and IFN-gamma-secreting T cells whereas the spleens of control groups did not. Moreover, adoptive transfer of splenocytes from successfully treated CT26 tumor-free mice protected naïve animals from a subsequent challenge with CT26, and this was mediated mainly by CD8 T cells. Most importantly, PDT plus IT-DC administered to one tumor site led to tumor regression at distant sites, including multiple lung metastases. PDT + IT-DC induces potent systemic antitumor immunity in mice and should be evaluated in the treatment of human cancer.

Mesenchymal Chondrosarcoma Treated With Total En Bloc Spondylectomy for 2 Consecutive Lumbar Vertebrae Resulted in Continuous Disease-Free Survival for More Than 5 Years

A case report of an extremely rare malignant spinal tumor successfully treated with total en bloc spondylectomy and chemotherapy. To describe points for consideration when an osteogenic lesion in the spine is diagnosed and treated. Primary mesenchymal chondrosarcoma in the spine is extremely rare. There were no reports of this tumor being treated with spondylectomy to achieve total surgical resection with a wide margin followed by chemotherapy. A 44-year-old female presented with low back pain and left flank pain. Magnetic resonance imaging and computerized tomography showed an osteosclerotic tumor of the lumbar vertebrae. Tc-99m HMDP bone scintigraphy was positive, but thallium-201 scintigraphy and gallium scintigraphy were negative. The patient was diagnosed as having chondrosarcoma based on biopsy findings. To resect the tumor completely, total en bloc spondylectomy for 2 consecutive lumbar vertebrae was performed. However, the postoperative pathologic diagnosis was extremely difficult because the patient was initially suspected to have osteosarcoma, but the final diagnosis was mesenchymal chondrosarcoma. Five years after surgery, there have not been any signs of local recurrence or distant metastasis, and the patient has remained continuously disease free. To our knowledge, we reported the first case of mesenchymal chondrosarcoma occurring from the lumbar spine treated with total en bloc spondylectomy and chemotherapy. Successful radical resection of the tumor could be accomplished. Although the effect of chemotherapy on the final results could not be clearly determined, considering that at least continuous disease-free survival was achieved, it is highly likely that chemotherapy contributed to the favorable results.

Multilayered and nanolayered hard nitride thin films deposited by cathodic arc evaporation. Part 2: Mechanical properties and cutting performances

The objective of this study is to investigate the performance of newly developed grades of nanolayer coated carbide tools for single point turning operation of difficult-to-cut alloys as Inconel 718. Nickel base alloys are difficult-to-machine materials because of their very good mechanical resistance at high temperature. Cemented carbide cutting tools, widely used for turning these alloys, are coated in order to promote their cutting lifetime. In this study, three compositions of multilayer coatings are deposited on cutting tools: CrN–TiN, TiN–AlTiN and CrN–AlTiN. These coatings, deposited in an industrial-size cathodic arc evaporation device, have approximately the same total thickness. Mechanical properties were first correlated to the period of these coatings. In a second time, the influence of this period, thickness of two successive nanolayers, was studied concerning turning performances. Mechanical and tribological properties are strongly dependant on coating structure (description in Part 1 [C. Ducros, C. Cayron, F. Sanchette, To be published in Surface and Coatings Technology]). The best mechanical properties were obtained with TiN/AlTiN nanolayers with 7 nm periods and superlattice structure. These coatings induced low main cutting force and low flank wear during Inconel 718 turning. Time life of superlattice TiN–AlTiN coated cutting tool is increased comparatively to CVD coated and AlTiN coated cutting tools currently used in production.

The influence of palaeotopography on facies architecture and pyroclastic flow processes of a lithic-rich ignimbrite in a high gradient setting: The Abrigo Ignimbrite, Tenerife, Canary Islands

The late Pleistocene (188 ± 19 ka) Abrigo Ignimbrite represents the last major explosive caldera-forming eruption on Tenerife. It consists almost entirely of a moderate volume (≫ 1.8 km 3) light grey phonolitic lithic-rich ignimbrite deposit, although a possible Abrigo Member thin fall deposit is locally preserved beneath the ignimbrite, suggesting an initial short-lived stable plinian eruption column. The ignimbrite deposit is dispersed radially around the lower flanks of the Las Cañadas edifice and correlates to a clast-supported lithic breccia on the eastern and northern caldera wall. Much of the ignimbrite was probably deposited offshore or within the caldera, now buried by more recent lavas. Two major depositional units, separated by a co-ignimbrite ash cloud deposit, and which display dramatic variations in thickness (< 1 to 25 m thick) and facies architecture across the radial drainage pattern, occur across most of the southern coastal plain of the island. Valley-ponded, massive, lithic-rich ignimbrite deposits were deposited by progressive aggradation from a sustained pyroclastic flow. Matrix-supported lithic block concentration zones within depositional units consist of either entrained, locally derived or vent-derived lithic clasts and were deposited in valleys during intervals of relatively high flow energy. Stratified ignimbrite veneer deposits on palaeoridges were deposited by incremental aggradation under pulsatory flow conditions. Valley-ponded to veneer deposit transitions, which occur over even subtle variations in topographic relief, were controlled by the bulk flow velocity, lithic-rich nature (high bulk density) and moderate volume of the pyroclastic flow system. Pumice-rich ignimbrite facies (matrix-supported pumice concentration zones; massive, pumice-rich ignimbrite lobes; planar and laterally complex stratified pumice-rich ignimbrite) were distributed at the deposit front or where the upper pumiceous part of the pyroclastic flow interacted with palaeoridges. Localised facies and bedforms were associated with complex topographic features. Multiple depositional units of massive, lithic-rich ignimbrite occur on the northern and western flanks of the Las Cañadas edifice. The steeper, more vegetated northern flanks also enhanced fines-depletion in the formation of clast-supported lithic breccia. Pyroclastic flows were channelised along and deposited within the same valleys that exist today and were commonly continuous and sheet-like across the interfluves. The basal zones of pyroclastic flows are envisaged as a bed-load of coarse lithic lapilli and blocks transported under their own momentum and with the support of the surrounding fine ash-gas granular flow.

Piggyback tectonics: Long-term growth of Kilauea on the south flank of Mauna Loa

Compositional and age data from offshore pillow lavas and volcaniclastic sediments, along with on-land geologic, seismic, and deformation data, provide broad perspectives on the early growth of Kilauea Volcano and the long-term geometric evolution of its rift zones. Sulfur-rich glass rinds on pillow lavas and volcaniclastic sediments derived from them document early underwater growth of a large compositionally diverse alkalic edifice. The alkalic rocks yield 40Ar / 39Ar ages as old as about 275 ka; transitional-composition lavas, which mark beginning of the shield stage while most or all the edifice remained below sea level, probably first erupted after about 150 ka, and tholeiitic lavas of present-day type are probably younger than 100 ka. Breccia clasts from Papau Seamount and along the lower southwest corner of the Hilina bench are derived from subaerial Mauna Loa, requiring that Mauna Loa's flank underlies western parts of Kilauea at shallow depth. The volume of the Kilauea edifice is therefore smaller (∼10,000 km 3) than previous estimates (15–40,000 km 3); lava-thickness accumulation rates appear to have remained nearly constant during edifice growth, as effusion rates increased from ∼25 × 10 6 m 3/yr at end of the alkalic stage to the present-day tholeiite rate of ∼100 × 10 6 m 3/yr. Seismic and gravity data show that the deep plumbing system for Kilauea's magma supply extends nearly vertically through the oceanic crust at least to mantle depths of 30–35 km, directly below its present-day caldera. Proximity of Kilauea's caldera to the surface boundary with Mauna Loa and the presence of Mauna Loa rocks at shallow depth beneath the south flank are difficult to reconcile with a submarine origin for early Kilauea alkalic lavas, unless geometric relations between the two volcanoes have changed substantially during growth of the Kilauea shield. Seismic and ground deformation data suggest seaward spreading of the entire south flank of Hawaii Island, independently of the boundary between Kilauea and Mauna Loa, along a landward-dipping detachment fault system near the basal contact of the composite volcanic edifices with underlying oceanic crust. Current steady-state horizontal displacements increase seaward, at rates of ∼1.5 cm/yr on the lower flank of Mauna Loa and reaching 5–8 cm/yr at the Kilauea coastline. Infrequent (∼100 yr?) large earthquakes generate similar geometries, but 10 2 larger displacements per event. Present-day Kilauea is the more dynamic edifice, but prior to inception of Kilauea and during its early growth, Mauna Loa is inferred to have undergone intense volcano spreading, involving the Kaoiki–Honuapo fault system (considered a geometric analog of the Hilina system on Kilauea). Cumulative deformation of Mauna Loa's south flank during growth of Kilauea since 200–300 ka is estimated to have involved > 10 km of seaward spreading, displacing the rift zones of Kīlauea while its deep plumbing system and summit magma reservoir remained nearly fixed in space. Kilauea's rift zones, rather than migrating southward with time solely due to dike emplacement preferentially on the mobile seaward side, alternatively are interpreted to have been transported passively southward, “piggyback” style, during shield-stage growth of Kilauea as a blister on the still-mobile south flank of Mauna Loa. Such an evolution of Kilauea accounts for the arcuate geometry of the present-day rift zones, proximity of the summit magma supply to the exposed flank of Mauna Loa, initial submarine growth of the ancestral edifice, and present-day location of Mauna Loa rocks at shallow depth beneath the south flank of Kilauea.

Thérèse Mound: a case study of coral bank development in the Belgica Mound Province, Porcupine Seabight

High-resolution seismic profiles, swath bathymetry, side-scan sonar data and video imageries are analysed in this detailed study of five carbonate mounds from the Belgica mound province with special emphasis on the well-surveyed Thérèse Mound. The selected mounds are located in the deepest part of the Belgica mound province at water depths of 950 m. Seismic data illustrate that the underlying geology is characterised by drift sedimentation in a general northerly flowing current regime. Sigmoidal sediment bodies create local slope breaks on the most recent local erosional surface, which act as the mound base. No preferential mound substratum is observed, neither is there any indication for deep geological controls on coral bank development. Seismic evidence suggests that the start-up of the coral bank development was shortly after a major erosional event of Late Pliocene–Quaternary age. The coral bank geometry has been clearly affected by the local topography of this erosional base and the prevailing current regime. The summits of the coral banks are relatively flat and the flanks are steepest on their upper slopes. Deposition of the encased drift sequence has been influenced by the coral bank topography. Sediment waves are formed besides the coral banks and are the most pronounced bedforms. These seabed structures are probably induced by bottom current up to 1 m/s. Large sediment waves are colonised by living corals and might represent the initial phase of coral bank development. The biological facies distribution of the coral banks illustrate a living coral cap on the summit and upper slope and a decline of living coral populations toward the lower flanks. The data suggest that the development of the coral banks in this area is clearly an interaction between biological growth processes and drift deposition both influenced by the local topography and current regime.

Cholodny–Went revisited: a role for jasmonate in gravitropism of rice coleoptiles

Gravitropism is explained by the Cholodny-Went hypothesis: the basipetal flow of auxin is diverted laterally. The resulting lateral auxin gradient triggers asymmetric growth. However, the Cholodny-Went hypothesis has been questioned repeatedly because the internal auxin gradient is too small to account for the observed growth asymmetry. Therefore, an additional gradient in indolyl-3-acetic acid (IAA) sensitivity has been suggested (Brauner and Hager in Planta 51:115-147, 1958). We challenged the Cholodny-Went hypothesis for gravitropism of rice coleoptiles (Oryza sativa L.) and found it to be essentially true. However, we observed, additionally, that the two halves of gravitropically stimulated coleoptiles responded differentially to the same amount of exogenous auxin: the auxin response is reduced in the upper flank but normal in the lower flank. This indicates that the auxin-gradient is amplified by a gradient of auxin responsiveness. Hormone contents were measured across the coleoptile by a GC-MS/MS technique and a gradient of jasmonate was detected opposing the auxin gradient. Furthermore, the total content of jasmonate increased during the gravitropic response. Jasmonate gradient and increase persist even when the lateral IAA gradient is inhibited by 1-N-naphtylphtalamic acid. Flooding with jasmonate delays the onset of gravitropic bending. Moreover, a jasmonate-deficient rice mutant bends more slowly and later than the wild type. We discuss a role of jasmonate as modulator of auxin responsiveness in gravitropism.

Wolf Volcano, Galápagos Archipelago: Melting and Magmatic Evolution at the Margins of a Mantle Plume

Wolf volcano, an active shield volcano on northern Isabela Island in the Galapagos Archipelago, has undergone two major stages of caldera collapse, with a phase of partial caldera refilling between. Wolf is a typical Galapagos shield volcano, with circumferential vents on the steep upper carapace and radial vents distributed in diffuse rift zones on the shallower-sloping lower flanks. The radial fissures continue into the submarine environment, where they form more tightly focused rift zones. Wolf ’s magmas are strikingly monotonous: estimated eruptive temperatures of the majority of lavas span a total of only 22 C. This homogeneity is attributed to buffering of magmas as they ascend through a thick column of olivine gabbroic mush that has been deposited from a thin, shallow (<2 km deep) subcaldera sill that is in a thermochemical steady state. Wolf ’s lavas have the most depleted isotopic compositions of any historically active intraplate ocean island volcano on the planet and have isotopic compositions (except for He/He) indistinguishable from midocean ridge basalt erupted from the Galapagos Spreading Center (GSC) 250–410 km away from the peak of influence of the Galapagos plume. Wolf ’s lavas are enriched in incompatible trace elements and have systematic major element differences relative to GSC lavas, however. Wolf ’s magmas result from lower extents of melting, deeper melt extraction, and a greater influence of garnet compared with GSC magmas, but Wolf and the GSC share the same sources. These melt generation conditions are attributed to melting in a thermal and mechanical boundary layer of depleted asthenosphere at the margins of the Galapagos plume. The lower degrees of melting and extraction from deeper levels result from a thicker lithospheric cap at Wolf than exists at the GSC.

Wear‐Resistant Titanium Carbonitride Coatings onto WC–Co Cutting Tools by Pulsed High‐Energy Density Plasma

Nanometer grain superhard ternary Ti(C,N) coatings with Vicker's nanohardness more than 50 GPa were deposited onto WC–Co cutting tools at ambient temperature using pulsed high‐energy density plasma coaxial gun. Young's modulus of the coated tools was about 550 GPa. Because of the continuously graded interfaces between the coatings and substrates, the coatings are well adherent to the tool substrates with very high critical load up to more than 100 mN measured by nanoscratch tester. The coefficients of friction were lower than 0.1. In contrast with the uncoated tools, the coated tools could be applied in turning hardened CrWMn steel at high speed under industrial conditions without lubricants, and the cutting performances were greatly improved with rather low flank wear and long tool life.

Collagen fiber orientation near dental implants in human bone: Do their organization reflect differences in loading?

This study is the first to investigate the collagen fiber orientation in human bone around titanium dental implants after loading. Birefringence under circularly polarized light (CPL) and scanning electron microscopy (SEM) investigation were used to assess both collagen orientation and density. Twenty osseointegrated dental implants were retrieved from the mandible bone of 10 patients and were used in the present study. The implants were retrieved after 6 months of function. The birefringence measurements were performed on digitized images using both the peri-implant bone (PB) and the alveolar bone (AB) retrieved at the moment of implant placing. All images detected at 100x were measured using a software image analysis. The results showed that 32.96% (3.208 +/- 0.435 mm(2)) of the PB area was composed of transverse collagen fibers while only 19.70% (1.957 +/- 0.253 mm(2)) was composed of longitudinally collagen fibers. In the AB 26.99% (2.620 +/- 0.520 mm(2)) of the examined area was composed of transverse collagen fibers while 22.25% (2.160 +/- 0.320 mm(2)) was composed of longitudinally collagen fibers. The CPL measurements of the birefringence indicated that the difference in area between the two collagen fibers orientations was statistically significant (p = 0.03) for both AB and PB. In PB the transverse collagen fibers were significantly increased (p < 0.01) than in AB; also the longitudinal collagen fibers differ significantly in the two groups (p = 0.02). The transverse collagen fibers in PB are more present under the lower flank of the threads where the load acts with a compression vectors, while outside the tip of the implant threads the collagen fibers run more longitudinally due to the loads that act with a tensile vectors. SEM observations showed, in the first collagen layers facing the implant surface, a random direction of the collagen fibers, while in the areas away from the implant surface the collagen fibers were well oriented and run parallel. In conclusion, in these loaded dental implants, the bone adjacent to the first two implant threads shows a significant increase of the amount of transverse collagen fibers that were mainly associated with the lower flank of the threads where compressive load acts. The longitudinal collagen fibers also differs significantly from those found in the AB.

Calcium antagonists inhibit bending and differential ethylene production of gravistimulated Ornithogalum ‘Nova’ cut flower spikes

Abstract To study the role of calcium ions in the gravitropic response of cut flowering shoots, we have examined the effects of various calcium modulators on stem bending of Ornithogalum spp. ‘Nova’ spikes following dry or wet gravistimulation. The most effective calcium chelators were further examined for their effects on the gravity- or IAA-induced ethylene formation, which represent signal transduction events in the gravity signalling pathway. The calcium chelators 1,2-bis(2-aminophenoxy)ethane- N , N , N ′, N ′-tetraacetic acid (BAPTA), ethylene glycol bis(β-aminoethylether) N , N , N ′, N ′-tetraacetic acid (EGTA), trans -1,2-cyclohexane dinitro- N , N , N ′, N ′-tetraacetic acid (CDTA), ethylenediamine-tetraacetic acid (EDTA), and the calcium channel blocker LaCl 3 , inhibited the gravitropic bending of Ornithogalum ‘Nova’ spikes. This bending inhibition was obtained following stem gravistimulation both under dry transport (48 h dark at 6 °C) or laboratory (24 h light at 20 °C) conditions. On the other hand, the calcium ionophore A23187 enhanced the gravitropic response, further supporting the role of intracellular calcium in the gravitropic bending response. These calcium modulators had no deleterious effects on the flowering shoot, indicating that their inhibitory effect is not due to damage. An ethylene gradient was developed across the gravistimulated flowering shoot prior to the visual bending response, in favour of the lower stem flank. This was correlated with higher levels of 1-aminocylclopropane-1-carboxylic acid (ACC) and 1-(malonylamino)-cyclopropane-1-carboxylic acid (MACC) at the lower flank, indicating that the gravitropic stimulus may either lead to activation of ethylene biosynthesis enzymes or to lateral ACC movement. The ethylene gradient was abolished following spikes pulsing with EGTA or CDTA, which prevented the increased ethylene production at the lower flank. CDTA also abolished the IAA-induced ethylene production in vertical stems. This may imply that the calcium chelators inhibit ethylene production of the lower flank via inhibition of IAA action, which induces increased ethylene formation. This indicates that the calcium chelators act upstream to activation of ethylene biosynthesis, probably by abolishing earlier gravity-related processes. Our results further support our previous findings in snapdragon that calcium may act as an important mediator of the gravitropic signal transduction mechanism in cut flowering shoots.

Geo-volcanological, mineralogical and environmental aspects of quarry materials related to pleural neoplasm in the area of Biancavilla, Mount Etna (Eastern Sicily, Italy)

The town of Biancavilla, located on the lower flanks of Mt. Etna volcano, eastern Sicily (Italy), showed high mortality rates owing to malignant pleural neoplasms, a cause of death specifically related to exposure to asbestos fibres. An environmental survey indicated the stone quarry site of “Il Calvario” as a possible source of asbestos fibre exposure, while a mineralogical study allowed to identify the new asbestiform mineral “fluoro-edenite”. A joint epidemiological and environmental study was conducted to assess the characteristics of the outbreak of malignant mesothelioma and to test the assumption of a causal relation with exposure to fluoro-edenite. Due to the lack of awareness of fluoro-edenite releases, Il Calvario may not be the only source of the fibre, but is probably the main one. The evolution of the volume of material quarried from Il Calvario was studied on the basis of maps printed from 1896 to 1995, by using a digital elevation model. The natural and anthropogenic causes of the territorial spread of the newly discovered amphibole fibres are discussed relatively to a geo-volcanological, territorial and environmental evolution of the area affected.

Depletion of lymphocytes, but not neutrophils, via apoptosis in a murine model of Vibrio vulnificus infection

Vibrio vulnificus causes severe sepsis in humans. There are several reports about the relationship between host immunity and bacterial growth in V. vulnificus infection. However, the effect on leukocytes of V. vulnificus infection in vivo has not been elucidated. A murine model of V. vulnificus infection was used to investigate its effects on leukocytes in this study. Bacteria were recovered from the blood of mice 3 h after subcutaneous injection in the right lower flank. They were detected in 87.5 % (n = 7/8) of mice at 6 h, but this value decreased to 12.5 % (n = 1/8) at 12 h. In contrast, the number of lymphocytes in peripheral blood had already started to decrease at 3 h, and reached a minimum at 6-9 h post-inoculation. Typical DNA laddering, a hallmark of apoptosis, was also detected in thymocytes and splenocytes at 6 and 9 h, and showed a tendency to disappear by 12 h. Although the number of lymphocytes decreased in the model, the numbers of neutrophils did not. These results suggested that V. vulnificus has selective cytotoxicity for lymphocytes in peripheral blood in vivo, and the lymphocyte depletion was probably associated with apoptosis in vivo.

Pure primary squamous cell carcinoma of the ovary: a case report and review of the literature

Pure primary squamous cell carcinoma of the ovary: a case report and review of the literature

Insight into Mt. Etna (Italy) kinematics during the 2002–2003 eruption as inferred from seismic stress and strain tensors

Seismic activity linked to the 2002–03 Mt. Etna eruption was investigated by analyzing the Md &gt; 2.3 earthquakes. The results of 3D relocation were used to compute fault plane solutions and a selected dataset was inverted to determine stress and strain tensors. The analysis revealed a complex kinematic response of the eastern flank dominated by fast stress propagation and reorientation. We hypothesize that a vertical dike intruded the southern flank, generating an extensional regime that triggered a radial intrusion in the northeast sector of the volcano. The combined effects gave rise to a rotation of the stress tensor that controlled the activation of the Pernicana fault system. The volcanic and tectonic interactions produced a second reorientation of the stress tensor, causing a structural response in the southeast lower flank. The overall result of the deformation processes observed during the eruption was an E‐W extension on the eastern flank of the volcano.

Recent eruptive history of Stromboli (Aeolian Islands, Italy) determined from high‐accuracy archeomagnetic dating

The “large sample method” of archeomagnetic dating was applied to Stromboli. 127 samples (10 sites) yielded paleofield directions with 95% confidence intervals less than 2°. Coupled with a reference curve for secular variation in western Europe, these allow accurate dating of volcanic events. A lava flow underlying San Bartolo village gave a minimum age of AD 100 (±100); a lava overflow predating the last sector collapse was dated from 1350 (±60), suggesting the recent occurrence of highly hazardous events. Lava spatters and a hot avalanche high on the northern flank were emplaced during the XXth century; lava spatters on the lower flanks could date the onset of the still‐ongoing phase from AD 550 (±50). These results are different from those obtained in a recent study, probably because traditional paleomagnetic sampling cannot yield sufficient precision, considering the characteristics of the archeomagnetic secular variation curve.

Effect of age on leather and skin traits of slaughter ostriches

Little is known about the factors affecting leather and skin traits in ostriches. The effect of age on physical skin traits of slaughter ostriches was consequently investigated. Forty skins representing slaughter ages ranging from five to 14 months were selected to represent means of the respective age groups with regard to skin size and slaughter weight. It was evident that leather thickness increased with age. A similar tendency was observed for tensile strength. The number of nodules/dmฒ declined by 2.8 nodules per month increase in slaughter age. Average nodule diameter increased at a rate of 0.08 mm per month of age. The number of nodules/dmฒ decreased towards body positions situated nearer to the ventral aspect of the ostrich (upper leg and lower flank). Positions nearer to the centre back had more nodules/dmฒ. The nodules on the neck and mid-crown area were smaller in diameter than those situated on the other body positions, with little difference between the upper leg, lower flank and butt positions. Repeatability estimates for the physical skin traits were in the medium to high range. Age thus affects physical leather traits to a lesser extent, apart from leather thickness. It does, however, exert an important influence on the nodule traits that were considered, and needs to be considered in the marketing of ostrich leather. Key Words: Leather thickness, Nodule diameter, Nodule distribution, Slit tear strength, Tensile strength SA Jnl Animal Sci Vol.34(2) 2004: 80-86

Fluid circulation and structural discontinuities inside Misti volcano (Peru) inferred from self-potential measurements

One of the seven potentially active andesite stratovolcanoes in southern Peru, Misti (5822 m), located 17 km northeast and 3.5 km above Arequipa, represents a major threat to the population (∼900,000 inhabitants). Our recent geophysical and geochemical research comprises an extensive self-potential (SP) data set, an audio–magnetotelluric (AMT) profile across the volcano and CO 2 concentrations in the soil along a radial profile. The SP survey is the first of its kind in providing a complete mapping of a large andesitic stratovolcano 20 km in diameter. The SP mapping enables us to analyze the SP signature associated with a subduction-related active volcano. The general SP pattern of Misti is similar to that of most volcanoes with a hydrogeologic zone in the lower flanks and a hydrothermal zone in the upper central area. A quasi-systematic relationship exists between SP and elevation. Zones with constant SP/altitude gradients (Ce) are observed in both hydrogeologic (negative Ce) and hydrothermal (positive Ce) zones. Transition zones between the different Ce zones, which form a concentric pattern around the summit, have been interpreted in terms of lateral heterogeneities in the lithology. The highest amplitudes of SP anomalies seem to coincide with highly resistive zones. The hydrothermal system 6 km in diameter, which extends over an area much larger than the summit caldera, may be constrained by an older, concealed collapse caldera. A sealed zone has apparently developed through alteration in the hydrothermal system, blocking the migration of CO 2 upward. Significant CO 2 emanations are thus observed on the lower flanks but are absent above the hydrothermal zone.

Variability of Turbulence and Its Outer Scales in a Model Tropopause Jet

Abstract Variability of flow regimes and turbulence scalings in a model of an inhomogeneously stratified, tropopause jet is investigated through high-resolution, forced, three-dimensional numerical simulations (with 512 or 1024 vertical levels). Multivalued scaling branches, with respect to the local gradient Richardson number (Rig), are shown to occur in several turbulent quantities (such as variances, fluxes, mixing efficiency, outer scales, and their ratios, etc.). Two distinct scaling curves are found for the upper and lower flanks of the jet, each showing a clear branch switching at a critical height. Distinct scaling curves in the upper and lower flanks of the jet can be related to the doubling of buoyancy frequency (N) in the background profile (across the model tropopause). The vertical levels corresponding to the inflection points (maximal shearing) in the quasi-equilibrium turbulent mean jet velocity profile is identified as the best criterion for branch switching along each of the scaling curve...

High Speed Machining of Bio-Titanium Alloy with a Binder-Less PcBN Tool

Using a binder-less PcBN tool, improvement of processing efficiency was tried in machining of a vanadium-free titanium alloy, Ti-6Al-2Nb-1Ta which was recently applied for a surgical implant material. The tool which is prepared through the direct conversion sintering of h-BN under both high pressure and temperature, exhibits an improved high thermal durability. It was confirmed that a binder-less PcBN tool exhibited lower flank wear and kept sharper cutting edge compared to the tools made of materials such as sintered carbide, conventional PcBN and polycrystalline diamond with Co-based binder, after turning in cutting speed of 4.2m/s, feed rate of 0.15mm/rev, depth of cut of 0.5mm under an application of a high pressure coolant. Also, milling tests were conducted with a radius end mill tool whose tip was made of the binder-less PcBN material. As a result, the possibility of high speed milling at cutting speed of 8.3m/s was found.