Modern Cone Research Articles

Retrospective evaluation of large settlements of a very soft clay: Alameda, California

The Harbor Bay Isle residential project in Alameda, CA, USA, comprises some 600 acres (243 ha) reclaimed from the margin of San Francisco Bay underlain by very soft (C c ∼ 1), high-water-content clay (e 0 > 2): San Francisco Bay Mud. Settlements of as much as 2.5 m developed from about 7 m (varying across the site) of sandfill surcharge, with records over some 43 years extending through primary consolidation and into secondary consolidation (creep). Iterative numerical modelling using large-strain theory (implemented in the Microsoft Excel software program), constrained by in situ void ratios and oedometer trends, achieved close matches with settlement histories over the full 43 years for the three locations considered, each of which displayed a markedly different history from the others. The presence or absence of a dried ‘crust’ was found unimportant; instead, the proportion of subunits within the Bay Mud controlled the evolution of settlements. Subunits within Bay Mud, evident in modern cone penetration test soundings (which were not available during the reclamation works), exist across the region and have systematically different states and properties. Further, while ageing is a factor, depositional conditions of the Bay Mud have produced a residual fabric that presents as a component of the pre-consolidation pressure.

Hypsobathymetric Models of Ksudach Caldera Complex (Kamchatka)

The Ksudach volcano is one of the most complicated and dynamic volcanic centre of the Russian Far East located on the south of Kamchatka peninsula. Modern cone of the volcano is composite construction with five different size and time calderas, two lakes and recent Shtubel’s cone. Studying of modern terrain dynamics on the volcano can be carried out with by comparison of two digital elevation (hypso- and bathy-) models for state of 80s in the 20 century (created on the data of aerial photographs and the bathymetric surveys) and for modern state (on the data of ArcticDEM and digital echosounding bathymetric survey with synchronized satellite fixation of the profiles). The elevation models like these (for Kamchatka’s volcanes and for different it’s conditions) were created at the first time. Its comparison allowed us to recognize new underwater extrusion dome with extensive underwater gas-hydrothermal outlets. Besides this we got the possibilities for clear bordering of different-time calderas using fractures on the automatic traceabled small river profiles. Comparison of high-resolution different-time DEMs for volcanic research is relatively new and perspective way for understanding volcanic life and development.

A Direct Metal Laser Sintering (DMLS) Root Analogue Implant Placed in the Anterior Maxilla: Case Report

Background: Today, modern cone beam computed tomography (CBCT) acquisition and three-dimensional (3D) image processing, combined with the direct metal laser sintering (DMLS) process, allows the production of custom-made, rootanalogue implants (RAIs). Purpose: The aim of the present report was to demonstrate how DMLS technology allows the production of a customized titanium RAI, which can be immediately inserted and restored in a fresh extraction socket of the anterior maxilla. Materials and methods: A customized DMLS titanium RAI, perfect copy of the radicular unit needed for replacement was fabricated and inserted into a fresh extraction socket of the esthetic area of the anterior maxilla. Results: After 1 year of follow-up, the DMLS RAI implant showed a satisfactory functional and esthetic integration, with no bone resorption or soft tissue recessions. Conclusions: The production of customized DMLS RAIs opens new interesting perspectives for immediate implantation.

Evolution of phototransduction, vertebrate photoreceptors and retina

Evidence is reviewed from a wide range of studies relevant to the evolution of vertebrate photoreceptors and phototransduction, in order to permit the synthesis of a scenario for the major steps that occurred during the evolution of cones, rods and the vertebrate retina. The ancestral opsin originated more than 700Mya (million years ago) and duplicated to form three branches before cnidarians diverged from our own lineage. During chordate evolution, ciliary opsins (C-opsins) underwent multiple stages of improvement, giving rise to the 'bleaching' opsins that characterise cones and rods. Prior to the '2R' rounds of whole genome duplication near the base of the vertebrate lineage, 'cone' photoreceptors already existed; they possessed a transduction cascade essentially the same as in modern cones, along with two classes of opsin: SWS and LWS (short- and long-wave-sensitive). These cones appear to have made synaptic contact directly onto ganglion cells, in a two-layered retina that resembled the pineal organ of extant non-mammalian vertebrates. Interestingly, those ganglion cells appear to be descendants of microvillar photoreceptor cells. No lens was associated with this two-layered retina, and it is likely to have mediated circadian timing rather than spatial vision. Subsequently, retinal bipolar cells evolved, as variants of ciliary photoreceptors, and greatly increased the computational power of the retina. With the advent of a lens and extraocular muscles, spatial imaging information became available for central processing, and gave rise to vision in vertebrates more than 500Mya. The '2R' genome duplications permitted the refinement of cascade components suitable for both rods and cones, and also led to the emergence of five visual opsins. The exact timing of the emergence of 'true rods' is not yet clear, but it may not have occurred until after the divergence of jawed and jawless vertebrates.

Molecular control of normal and acrocona mutant seed cone development in Norway spruce (Picea abies) and the evolution of conifer ovule‐bearing organs

Reproductive organs in seed plants are morphologically divergent and their evolutionary history is often unclear. The mechanisms controlling their development have been extensively studied in angiosperms but are poorly understood in conifers and other gymnosperms. Here, we address the molecular control of seed cone development in Norway spruce, Picea abies. We present expression analyses of five novel MADS-box genes in comparison with previously identified MADS and LEAFY genes at distinct developmental stages. In addition, we have characterized the homeotic transformation from vegetative shoot to female cone and associated changes in regulatory gene expression patterns occurring in the acrocona mutant. The analyses identified genes active at the onset of ovuliferous and ovule development and identified expression patterns marking distinct domains of the ovuliferous scale. The reproductive transformation in acrocona involves the activation of all tested genes normally active in early cone development, except for an AGAMOUS-LIKE6/SEPALLATA (AGL6/SEP) homologue. This absence may be functionally associated with the nondeterminate development of the acrocona ovule-bearing scales. Our morphological and gene expression analyses give support to the hypothesis that the modern cone is a complex structure, and the ovuliferous scale the result of reductions and compactions of an ovule-bearing axillary short shoot in cones of Paleozoic conifers.

Accuracy and speed of robotic assisted needle interventions using a modern cone beam computed tomography intervention suite: a phantom study

To analyse the feasibility and accuracy of robotic aided interventions on a phantom when using a modern C-arm-mounted cone beam computed tomography (CBCT) device in combination with needle guidance software. A small robotic device capable of holding and guiding needles was attached to the intervention table. After acquiring a 3D data set the access path was planned on the CBCT workstation and shown on the intervention monitor. Then the robot was aligned to the live fluorosopic image. A total of 40 punctures were randomly conducted on a phantom armed with several targets (diameter 2 mm) in single and double oblique trajectory (n = 20 each). Target distance, needle deviation and time for the procedures were analysed. All phantom interventions (n = 40) could be performed successfully. Mean target access path within the phantom was 8.5 cm (min 4.2 cm, max 13.5 cm). Average needle tip deviation was 1.1 mm (min 0 mm, max 4.5 mm), time duration was 3:59 min (min 2:07 min, max 10:37 min). When using the proposed robot device in a CBCT intervention suite, highly accurate needle-based interventional punctures are possible in a reasonable timely manner in single as well as in double oblique trajectories.

Retesting of Liquefaction and Nonliquefaction Case Histories from the 1976 Tangshan Earthquake

A field investigation was performed to retest liquefaction and nonliquefaction sites from the 1976 Tangshan earthquake in China. These sites were carefully investigated in 1978 and 1979 by using standard penetration test (SPT) and cone penetration test (CPT) equipment; however, the CPT measurements are obsolete because of the now nonstandard cone that was used at the time. In 2007, a modern cone was mobilized to retest 18 selected sites that are particularly important because of the intense ground shaking they sustained despite their high fines content and/or because the site did not liquefy. Of the sites reinvestigated and carefully reprocessed, 13 were considered accurate representative case histories. Two of the sites that were originally investigated for liquefaction have been reinvestigated for cyclic failure of fine-grained soil and removed from consideration for liquefaction triggering. The most important outcome of these field investigations was the collection of more accurate data for three nonliquefaction sites that experienced intense ground shaking. Data for these three case histories is now included in an area of the liquefaction triggering database that was poorly populated and will help constrain the upper bound of future liquefaction triggering curves.

Prediction of worn geometry in cone crushers

A cone crusher is used for crushing rock material in mines and quarries. The performance of the crusher changes during its lifetime due to wear of the crusher liners. Previous research has made it possible to model, simulate and optimize the performance of a given crusher. A problem is that due to wear the optimized geometry will change and the performance will suffer. To design crusher geometry for optimized performance throughout the lifetime of the liners, it is desirable to predict the worn geometry. This paper presents a method for this purpose. In a previous study, a wear model was investigated for a laboratory scale crusher. This model has been implemented in a cone crusher. The controller in a modern cone crusher can, for example, keep the close side setting or the power draw constant. Such a controller was implemented in the model. Measurements of the worn geometry were conducted in order to validate the wear model. The worn geometry is well predicted although the wear rate, estimated from experiments presented in a previous study, was overestimated. The effect of constant power control and wear on various output parameters was studied in simulations.

Pityostrobusmillerisp. nov., a pinaceous cone from the Lower Cretaceous (Aptian) of southwestern Russia

A new species of permineralized Pityostrobus cone, Pityostrobus milleri Falder et al., sp. nov. has been discovered in a calcareous nodule from shallow marine sediments of Early Cretaceous (latest Aptian; Clansenian) age in the Caucasus Mountains in southwestern Russia. Nodules of this type also contain wood fragments, gastropods, bivalves, and an extremely rich assemblage of well preserved cephalopods. Russian spore and pollen analyses indicate that deposition in this region may have occurred during a temperate climate regime. The cone is cylindrical, about 2.5 cm in diameter and individual scales contain up to 17 resin canals and 18 vascular strands. Although the fossil displays many features of modern Pinus cones, including inflated scale apexes, resin canals abaxial to vascular tissue in scale base, and scale strands curved on the adaxial side, it cannot be assigned to Pinus because the bract and scale trace are not united at their origin. Tunneled borings in the cortex of the cone axis are tightly packed with frass, and resemble tunnels of modern cone boring beetles such as Conophthorus. This cone further documents the worldwide diversity of pinaceous conifers during the Cretaceous, and demonstrates a well developed syndrome of insect herbivory in the Pinaceae by the late Mesozoic.

Metal-residence sites in lavas and tuffs from Volc�n Popocat�petl, Mexico: implications for metal mobility in the environment

Volcan Popocatepetl is a Quaternary stratovolcano located 60 km southeast of Mexico City. The summit crater is the site of recent ash eruptions, excess degassing, and dacite dome growth. The modern cone comprises mainly pyroclastic flow deposits, airfall tephras, debris flows, and reworked deposits of andesitic composition; it is flanked by more mafic monogenetic vents. In least-degassed fallout tuffs and mafic scoria, transition metals are concentrated in phases formed before eruption, during eruption, and after eruption. Preeruptive minerals occur in both lavas and tephra, and include oxides and sulfides in glass and phenocrysts. The magmatic oxides consist of magnetite, ilmenite, and chromite; the sulfides consist of both (Fe,Ni)1-xS (MSS) and Cu–Fe sulfide (ISS). Syn- and posteruptive phases occur in vesicles in both lavas and tephra, and on surfaces of ash and along fractures. The mineral assemblages in lavas include Cu–Fe sulfide and Fe–Ti oxide in vesicles, and Fe sulfide and Cu–Fe sulfide in segregation vesicles. Assemblages in vesicles in scoria include Fe–Ti oxide and rare Fe–Cu–Sn sulfide. Vesicle fillings of Fe–Ti oxide, Ni-rich chromite, Fe sulfide, Cu sulfide, and barite are common to two pumice samples. The most coarse-grained of the vesicle fillings are Cu–Fe sulfide and Cu sulfide, which are as large as 50 μ in diameter. The youngest Plinian pumice also contains Zn(Fe) sulfide, as well as rare Ag–Cu sulfide, Ag–Fe sulfide, Ag bromide, Ag chloride, and Au–Cu telluride. The assemblage is similar to those typically observed in high-sulfidation epithermal mineralization. The fine-grained nature and abundance of syn- and/or posteruptive phases in porous rocks makes metals susceptible to mobilization by percolating fluids. The abundance of metal compounds in vesicles indicates that volatile exsolution prior to and/or during eruption played an important role in releasing metals to the atmosphere.

New comminution applications using hydrocone crushers with setting regulation in real time

The setting (distance between mantle and concave ring) of the Hydrocone cone crusher is altered, even with the crusher operating at full load, by lifting or lowering the mantle by means of a hydraulic piston (Hydroset). Modern developments in the field of electronics and microcomputers have made it possible to design a small, reliable and very sophisticated system for automatic regulation of the setting of a Hydrocone crusher. The system monitors energy consumption, crushing force and setting and continuously adapts the crusher to even small variations in the feed and/or operating conditions. This technology has expanded the range of applications that can be successfully solved with cone crushers. In the paper we will give a general description of modern cone crusher technology and also give some examples of new possible applications. Fine crushing in closed circuit with a screen can, thanks to automation and carefully designed crushing chambers, compete with rod mills. Products smaller than 3 mm are common. Another example is the crushing of a gold ore to −10 mm, in open circuit, with a Hydrocone crusher. The automation system ensures that the crusher runs at the smallest possible setting and thus ensures that the correct discharge is produced. In some applications it is interesting to operate cone crushers in a wet process. About 20 years ago, Allis Mineral Systems installed the first Hydrocones with water injected together with the feed. These crushers are still in operation and we will present our experiences. Small flexible cone crushers with computer control can be used to create more cost efficient ore crushing plants than the conventional installations with few large machines. The “crushing cassette” idea is presented.

PITYOSTROBUS MAKAHENSIS, A NEW SPECIES OF SILICIFIED PINACEOUS SEED CONE FROM THE MIDDLE TERTIARY OF WASHINGTON

A single structurally preserved ovulate cone forms the basis for the description of a new species of Pityostrobus from the early Oligocene of the Olympic Peninsula of Washington. The specimen consists of about two‐thirds of a cylindrical cone. In living condition the cone was 8–10 cm long and 3.5–4 cm in diameter. Critical features of the cone include decurrent bract bases, an elongate bract‐scale adnation, perpendicular disposition of the proximal part of the scale, and seeds with vesciculate seed coat. An unusual feature of the cone is a distinctive cortical region of thin‐walled parenchyma, mineral‐filled lacunae, and resin canals. This region can be traced to the adaxial side of the scale where it can be recognized by an extensive development of resin canals in the adaxial ground tissue opposite the seed cavities, and by distinctive lacunae around the vascular bundles. The fossil shares several significant characters with modern cones of Abies, Pseudotsuga, Larix, Tsuga, and Picea, thereby calling to question the abietoid/pinoid division of the family, or suggesting that abietoid and pinoid genera of the early Oligocene had not yet diverged to the extent seen in the modern flora.

A NEW TAXODIACEOUS SEED CONE FROM THE OLIGOCENE OF WASHINGTON

Cunninghamiostrobus goedertii is described as a new species based on permineralized seed cones from the Early Oligocene of Washington. The fossils come from the Makah Formation and were found on the northern shore of the Olympic Peninsula. The cone consists of numerous bract‐scale complexes arranged helically around a central axis. Each bract‐scale complex has a large bract bearing a small flap of tissue adaxially that represents the ovuliferous scale. Up to three seeds were produced on each complex. The vascular trace to the bract‐scale complex diverges from the vascular cylinder of the cone axis as a concentric strand. This divides in the outer cortex of the axis to form a large collateral bract tract abaxially and a minute scale trace adaxially. The latter continues outward to supply the ovuliferous scale. The bract trace divides, forming many strands outward which occur in a row with transfusion tissue between them. Many resin canals also occur in the bract. The new cone combines features found in modern cones of Athrolaxis, Cunninghamia, and Taiwania but is most similar to Cunninghamiostrobus yubariensis from the Late Cretaceous of Japan.

A New Taxodiaceous Seed Cone from the Oligocene of Washington

Cunninghamiostrobus goedertii is described as a new species based on permineralized seed cones from the Early Oligocene of Washington. The fossils come from the Makah Formation and were found on the northern shore of the Olympic Peninsula. The cone consists of numerous bract-scale complexes arranged helically around a central axis. Each bract-scale complex has a large bract bearing a small flap of tissue adaxially that represents the ovuliferous scale. Up to three seeds were produced on each complex. The vascular trace to the bract-scale complex diverges from the vascular cylinder of the cone axis as a concentric strand. This divides in the outer cortex of the axis to form a large collateral bract tract abaxially and a minute scale trace adaxially. The latter continues outward to supply the ovuliferous scale. The bract trace divides, forming many strands outward which occur in a row with transfusion tissue between them. Many resin canals also occur in the bract. The new cone combines features found in modern cones of Athrolaxis, Cunninghamia, and Taiwania but is most similar to Cunninghamiostrobus yubariensis from the Late Cretaceous of Japan.

BIOMETRIC ANALYSIS OF MODERN AND LATE PLEISTOCENE CONES OF PICEA FROM WESTERN CANADA.

Late Pleistocene and early Holocene fossil Picea cones and modern cones of Picea sitchensis (Bong.) Carr. from Cape Ball, Queen Charlotte Islands, British Columbia were compared for morphological variability. Modern cones of P. sitchensis from Cape Ball are most similar to populations in the area of Prince Rupert, British Columbia. The fossil cones resemble most closely modern P. glauca (Moench) Voss. and allopatric P. sitchensis × P. glauca in cone size, scale size and phyllotaxy, which suggests introgression between P. sitchensis and P. glauca in late Pleistocene time on the north coast of British Columbia. These results suggest that P. glauca and P. sitchensis migrated northward shortly after deglaciation along the coast and that P. sitchensis maintained P. glauca cone characteristics before assuming more or less independent distributional ranges along the coast of British Columbia.

A gigantic Bezymianny-type event at the beginning of modern volcan Popocatepetl

The history of volcan Popocatepetl can be divided into two main periods: the formation of a large primitive volcano — approximatively 30 km wide — on which is superimposed a modern cone (6–8 km in diameter and 1700m high). A major event of Bezymianny type marks the transition between these two dissimilar periods. The activity of the primitive volcano was essentially effusive and lasted several hundred thousands of years. The total volume of products ejected by the volcano is of the order of 500–600 km3. Its last differentiated magmas are dacitic. A gigantic debris flow (D.F.) spread on the southern side is related to the Bezymianny-type event which destroyed the summit area of the ancient edifice. An elliptical caldera (⋍ 6.5 × 11 km wide) was formed by the landslide. Its deposits, with a typical hummocky surface, cover 300 km2 for a volume of 28–30 km3. Numerous outcrops belonging to this debris flow show “slabs” of more or less fractured and dislocated rocks that come from the primitive volcano. These deposits are compared to two studied debris flows of similar extent and volume: the Mount Shasta and Colima's D.F. This eruption takes a major place in the volcanologic and magmatic history of Popocatepetl: pyroclastic products of surge-type with “laminites” and crude layers, ashflows, and pumiceous airfall layers are directly related to this event and begin the history of the modern volcano probably less than 50,000 years ago. In addition, a second andesitic and dacitic phase rose both from the central vent — forming the basis of modern Popo — and from lateral vents. The terminal cone is characterized by long periods of construction by lava flows alternating with phases of destruction, the duration of these episodes being 1000 to 2000 years. The cone is composed of two edifices: the first, volcan El Fraile, began with effusive activity and was partly destroyed by three periods of intense explosive activity. The first period occurred prior to 10.000 years B.P., the second from 10.000 to 8000 years B.P. and the third from ⋍ 5000 to ⋍ 3800 years B.P. Each period of destruction shows cycles producing collapsing pyroclastic flows or nuees of the St Vincent-type related to the opening of large craters, plinian air-fall deposits and minor lava flows. The second edifice, the summit Popo, produced lava flows until 1200 years B.P. and since that time, entered into an explosive period. Two cataclysmic episodes, each including major pyroclastic eruptions, occurred 1200 and 900–1000 years ago. During the Pre-Hispanic and historic times effusive activity was restricted entirely to the summit area alternating with plinian eruptions. Nevertheless, despite the quiet appearance of the volcano, the last period of pyroclastic activity which started 1200 years ago may not have ended and can be very dangerous for the nearby populations.

Recent Lahars from Mount St. Helens, Washington

Late Recent eruptions of Mount St. Helens volcano in the Cascade Range of southern Washington have caused numerous lahars; some extend more than 40 miles down valleys west of the volcano. These lahars typically consist of poorly sorted and unstratified detritus derived almost wholly from the volcano. The lahars and inter-bedded fluvial gravel commonly form valley fills; such a fill in the valley of the North Fork of the Toutle River contains at least three lahars. Lahars from Mount St. Helens are composed mainly of nonvesicular rock fragments; thus, their great distance of transport is attributed to mobility provided by water rather than by gas emitted from particles in the matrix. Near the volcano, some of the lahars contain charred wood, proving that they were hot and resulted directly from eruptions. Wood from within a lahar in the fill in the North Fork of the Toutle River valley has a radiocarbon age of about 2000 years. The lahar consists of material derived from a Mount St. Helens volcano that existed before the present cone was built; thus, the present cone must be less than 2000 yearsold. In addition, interpretation of soil profiles younger than the dated wood suggests that the modern cone may have been built within the last thousand Years.

On the Age of the newest Lava Current of Auvergne, with remarks on some Tertiary Fossils of that Country.

Until my recent visit to Auvergne in 1843, I was never able to hear of the discovery of any fossils so connected with the most modern class of volcanic cones and currents of lava, as to enable us to assign to them any other than a very indefinite geological date. But when in the course of my last tour I inquired of the Abbé Croizet, well known as an eminent comparative osteologist, if he had yet found any fossil bones or shells in gravel lying immediately under the newest lava-streams, he replied that he had recently met with a great number of mammiferous remains at Nechers, in a bed of reddish sandy clay, which rested against the side of the long and narrow coulée which has issued from the Puy de Tartaret. This hill, as the readers of Scrope's ‘Geology of Auvergne’ will remember, is one which, by its position in the bottom of a valley at the lower end of the Lac de Chambon, and by the integrity of its heap of loose scoriæ, has all the characters belonging to the class of most modern cones, those which have been least altered by time. The lava issuing from it forms a narrow stripe, occupying for more than thirteen miles the bottom of the valley in which the river Couze de Chambon flows, and at length terminating at the small town of Nechers, about six miles north-west of Issoire. At a short distance above the end of the current in