Physical constraints on magma contamination in the continental crust: an example, the Adamello complex

1984 ◽  
Vol 310 (1514) ◽  
pp. 457-472 ◽  
Keyword(s):  
Country Rock ◽  
Mafic Magma ◽  
Zone Melting ◽  
The Body ◽  
Fourth Power ◽  
Magma Body ◽  
Physical Constraints ◽  
Igneous Intrusions ◽  
Time Required ◽  
Sinking Velocity

Igneous intrusions may move upwards through the crust by zone melting, by penetrative intrusion, by sloping or by some combination of these three mechanisms. Each mechanism offers different opportunities for contamination of the magma by country rock. Both zone melting and sloping offer the greatest possibility of assimilation, but in most natural situations the maximum amount of country rock assimilable by a magma is considerably less than its own original volume. Thermal and other constraints limit the amount of ascent that a magma body may accomplish by either zone melting or sloping: once, and twice to three times the original height of the magma body respectively. The assimilability of a xenolith sinking in a magma (i.e. the possibility of reaching the bottom without fully melting) depends on the fourth power of the radius of the xenolith because the time required for assimilation increases as and the time available decreases as r2 (because of increased sinking velocity). This can explain the observed size distribution of xenoliths in some intrusions. Applied to the Tertiary Adamello igneous complex of northern Italy, these considerations suggest that the intrusion may have been initiated by the emplacement of a mafic magma body in the lower crust. The body remained gravitationally stable until its composition had been modified and its density so lowered by zone melting of its roof that it began to ascend through the crust by either penetrative or sloping processes. The intrusion finally solidified at a depth of between six and ten kilometres and the last stages of emplacement occurred by sloping. The complex comprises a number of separate intrusions and this process was repeated seven or more times over a 10 Ma period (between 30 and 40 Ma). Each episode of intrusion, however, lasted less than 1 Ma

scholarly journals Preparation and Pharmacokinetic Study of Daidzein Long-Circulating Liposomes

2019 ◽  
Vol 14 (1) ◽  
Author(s):  
Qiao Wang ◽  
Wenjin Liu ◽  
Junjun Wang ◽  
Hong Liu ◽  
Yong Chen
Keyword(s):  
Single Dose ◽  
Drug Concentration ◽  
Drug Loading ◽  
Plasma Drug Concentration ◽  
The Body ◽  
Molar Ratio ◽  
Terminal Phase ◽  
Plasma Drug ◽  
Ultrasonic Time ◽  
Time Required

Abstract In this study, daidzein long-circulating liposomes (DLCL) were prepared using the ultrasonication and lipid film-hydration method. The optimized preparation conditions by the orthogonal design was as follows: 55 to 40 for the molar ratio of soybean phosphatidylcholine (SPC) to cholesterol, 1 to 10 for the mass ratio of daidzein to total lipid (SPC and cholesterol) (w:w), the indicated concentration of 5% DSPE-mPEG2000 (w:w), 50 °C for the hydration temperature, and 24 min for the ultrasonic time. Under these conditions, the encapsulation efficiency and drug loading of DLCL were 85.3 ± 3.6% and 8.2 ± 1.4%, respectively. The complete release times of DLCL in the medium of pH 1.2 and pH 6.9 increased by four- and twofold of that of free drugs, respectively. After rats were orally administered, a single dose of daidzein (30 mg/kg) and DLCL (containing equal dose of daidzein), respectively, and the MRT0−t (mean residence time, which is the time required for the elimination of 63.2% of drug in the body), t1/2 (the elimination half-life, which is the time required to halve the plasma drug concentration of the terminal phase), and AUC0−t (the area under the plasma drug concentration-time curve, which represents the total absorption after a single dose and reflects the drug absorption degree) of daidzein in DLCL group, increased by 1.6-, 1.8- and 2.5-fold as compared with those in the free group daidzein. Our results indicated that DLCL could not only reduce the first-pass effect of daidzein to promote its oral absorption, but also prolong its mean resident time to achieve the slow-release effect.

scholarly journals A Feasibility Study of Kinematic Characteristics on the Upper Body According to the Shooting of Elite Disabled Archery Athletes

2021 ◽  
Vol 18 (6) ◽  
pp. 2962
Author(s):  
Tae-Whan Kim ◽  
Jae-Won Lee ◽  
Seoung-Ki Kang ◽  
Kyu-Yeon Chae ◽  
Sang-Hyup Choi ◽  
...  
Keyword(s):  
The Body ◽  
Lower Limbs ◽  
Upper Body ◽  
Movement Trajectory ◽  
Phase 2 ◽  
Kinematic Characteristics ◽  
Significant Difference ◽  
Athletes With Disabilities ◽  
Body Center ◽  
Time Required

The purpose of this study is to compare and analyze the kinematic characteristics of the upper limb segments during the archery shooting of Paralympic Wheelchair Class archers (ARW2—second wheelchair class—paraplegia or comparable disability) and Paralympic Standing Class archers (ARST—standing archery class—loss of 25 points in the upper limbs or lower limbs), where archers are classified according to their disability grade among elite disabled archers. The participants of this study were selected as seven elite athletes with disabilities by the ARW2 (n = 4) and ARST (n = 3). The analysis variables were (1) the time required for each phase, (2) the angle of inclination of the body center, (3) the change of trajectory of body center, and (4) the change of the movement trajectory of the bow center by phase when performing six shots in total. The ARW2 group (drawing phase; M = 2.228 s, p < 0.05, holding phase; M = 4.414 s, p < 0.05) showed a longer time than the ARST group (drawing phase; M = 0.985 s, holding phase; M = 3.042 s), and the angle of the body did not show a significant difference between the two groups. Additionally, in the direction of the anteroposterior axis in the drawing phase, the change in the movement trajectory of the body center showed a more significant amount of change in the ARW2 group than in the ARST group, and the change in the movement trajectory of the bow center did not show a significant difference between the two groups.

scholarly journals Natural barriers: waterfall transit by small flying animals

2020 ◽  
Vol 7 (8) ◽  
pp. 201185
Author(s):  
Victor M. Ortega-Jimenez ◽  
Eva C. Herbst ◽  
Michelle S. Leung ◽  
Robert Dudley
Keyword(s):  
Complex Dynamics ◽  
Sister Group ◽  
The Body ◽  
Heterogeneous Structure ◽  
Flight Behaviour ◽  
Physical Constraints ◽  
Physical Barriers ◽  
Translational Speed ◽  
Geomorphological Features ◽  
Stroke Amplitude

Waterfalls are conspicuous geomorphological features with heterogeneous structure, complex dynamics and multiphase flows. Swifts, dippers and starlings are well-known to nest behind waterfalls, and have been reported to fly through them. For smaller fliers, by contrast, waterfalls seem to represent impenetrable barriers, but associated physical constraints and the kinematic responses of volant animals during transit are unknown. Here, we describe the flight behaviour of hummingbirds (the sister group to the swifts) and of various insect taxa as they fly through an artificial sheet waterfall. We additionally launched plastic balls at different speeds at the waterfall so as to assess the inertial dependence of sheet penetration. Hummingbirds were able to penetrate the waterfall with reductions in both their translational speed, and stroke amplitude. The body tilted more vertically and exhibited greater rotations in roll, pitch and yaw, along with increases in tail spread and pitch. The much smaller plastic balls and some flies moving at speeds greater than 2.3 m s −1 and 1.6 m s −1 , respectively, also overcame effects of surface tension and water momentum and passed through the waterfall; objects with lower momentum, by contrast, entered the sheet but then fell along with the moving water. Waterfalls can thus represent impenetrable physical barriers for small and slow animal fliers, and may also serve to exclude both predators and parasites from nests of some avian taxa.

Series Active Variable Geometry Suspension Robust Control Based on Full-Vehicle Dynamics

2019 ◽  
Vol 141 (5) ◽  
Author(s):  
Cheng Cheng ◽  
Simos A. Evangelou
Keyword(s):  
High Performance ◽  
Performance Enhancement ◽  
Ride Comfort ◽  
The Body ◽  
Control Technique ◽  
Variable Geometry ◽  
Physical Constraints ◽  
Car Model ◽  
Time Domains ◽  
Vertical Accelerations

This paper demonstrates the ride comfort and road holding performance enhancement of the new road vehicle series active variable geometry suspension (SAVGS) concept using an H∞ control technique. In contrast with the previously reported work that considered simpler quarter-car models, the present work designs and evaluates control systems using full-car dynamics thereby taking into account the coupled responses from the four independently actuated corners of the vehicle. Thus, the study utilizes a nonlinear full-car model that represents accurately the dynamics and geometry of a high performance car with the new double wishbone active suspension concept. The robust H∞ control design exploits the linearized dynamics of the nonlinear model at a trim state, and it is formulated as a disturbance rejection problem that aims to reduce the body vertical accelerations and tire deflections while guaranteeing operation inside the existing physical constraints. The proposed controller is installed on the nonlinear full-car model, and its performance is examined in the frequency and time domains for various operating maneuvers, with respect to the conventional passive suspension and the previously designed SAVGS H∞ control schemes with simpler vehicle models.

scholarly journals 3D Printed Laminated CaCO3-Nanocellulose Films as Controlled-Release 5-Fluorouracil

Polymers ◽  
2020 ◽  
Vol 12 (4) ◽  
pp. 986 ◽  
Author(s):  
Denesh Mohan ◽  
Nur Fatin Khairullah ◽  
Yan Ping How ◽  
Mohd Shaiful Sajab ◽  
Hatika Kaco
Keyword(s):  
Drug Delivery ◽  
Chemical Properties ◽  
Pharmaceutical Compounds ◽  
The Body ◽  
Therapeutic Effects ◽  
Layer By Layer ◽  
3D Printed ◽  
Time Required ◽  
Uptake And Release ◽  
And Chemical Properties

Drug delivery constitutes the formulations, technologies, and systems for the transport of pharmaceutical compounds to specific areas in the body to exert safe therapeutic effects. The main criteria for selecting the correct medium for drug delivery are the quantity of the drug being carried and the amount of time required to release the drug. Hence, this research aimed to improve the aforementioned criteria by synthesizing a medium based on calcium carbonate-nanocellulose composite and evaluating its efficiency as a medium for drug delivery. Specifically, the efficiency was assessed in terms of the rates of uptake and release of 5-fluorouracil. Through the evaluation of the morphological and chemical properties of the synthesized composite, the established 3D printing profiles of nanocellulose and CaCO3 took place following the layer-by-layer films. The 3D printed double laminated CaCO3-nanocellulose managed to release the 5-fluorouracil as an effective single composition and in a time-controlled manner.

The late Neoproterozoic Frog Lake hornblende gabbro pluton, Avalon Terrane of Nova Scotia: evidence for the origins of appinites

2010 ◽  
Vol 47 (2) ◽  
pp. 103-120 ◽  
Author(s):  
Georgia Pe-Piper ◽  
David J.W. Piper ◽  
Basilios Tsikouras
Keyword(s):  
Nova Scotia ◽  
Country Rock ◽  
Volcanic Rocks ◽  
Mafic Magma ◽  
Single Type ◽  
Structural Level ◽  
Element Abundances ◽  
Hornblende Gabbro ◽  
Late Neoproterozoic ◽  
Low K

The late Neoproterozoic Frog Lake pluton, in the Avalon terrane of the Cobequid Highlands, Nova Scotia, consists predominantly of hornblende gabbro. It shows petrographic similarities to water-rich mafic intrusions known as appinites that are present in some collisional orogens. This study aims to further understanding of the origin of appinitic intrusions. In the field, the main hornblende gabbro was intruded between screens of metasedimentary country rock that is of upper greenschist metamorphic grade. The contacts appear to have been pathways for magma of gabbroic, tonalitic–granodioritic, and granitic composition that carried enclaves of gabbroic lithologies. Some of these magmas had a high volatile content, resulting in abundance of hydrous mineral phases, pegmatites, and diffuse felsic segregations. These varied rocks in the contact zones experienced progressive shear resulting in syn-magmatic deformation. Low-Ti hornblende gabbros have trace-element abundances similar to subduction-related low-K mafic rocks, including some enrichment in large-ion lithophile elements and marked relative depletion in Nb and Y. High-Ti hornblende gabbros and pyroxene–mica gabbro show more alkaline characteristics, with higher amounts of Nb, Y, P2O5, and high-field-strength elements. Tonalite and granite veins are geochemically similar to volcanic-arc granite. Comparison with appinites in the literature suggests that the Frog Lake pluton represents a deeper structural level than most appinites. The Frog Lake appinites were part of the feeder system to back-arc volcanic rocks of the Jeffers Group. Comparison with other appinites also leads to the conclusion that there is not a single type of “appinitic magma”: different appinitic plutons range in composition from low-K calc-alkaline to shoshonitic. The essential characteristic is a water-rich mafic magma. Appinites occur in settings undergoing crustal-scale strike-slip shear, where the faults allow rapid rise of mafic magma to shallow crustal levels.

scholarly journals Spin-up in a tank induced by a rotating bluff body

1999 ◽  
Vol 388 ◽  
pp. 49-68 ◽  
Author(s):  
D. MAYNES ◽  
J. KLEWICKI ◽  
P. McMURTRY
Keyword(s):  
Steady State ◽  
Turbulent Diffusion ◽  
Bluff Body ◽  
Fluid Velocity ◽  
Tangential Velocity ◽  
The Body ◽  
Mean Flow ◽  
Velocity Fluctuations ◽  
Acceleration Rate ◽  
Time Required

Spin-up of a turbulent flow in a cylindrical tank caused by a rotating bluff body has been investigated using flow visualization, fluid velocity measurements, and hydrodynamic torque measurements. During the spin-up process three distinct temporal regimes exist. These regimes are: (i) a build-up regime where the torque and the tangential velocity fluctuations in the close proximity of the body remain constant; (ii) a decay regime where these quantities decay with power-law relations; and (iii) a mean flow steady state where these values remain relatively constant. Experiments were conducted in two tanks differing in volume by a factor of 80 and with a large range of bluff body sizes. A non-dimensional time scale, τ, based upon turbulent diffusion is determined and the tangential velocity fluctuations and torque coefficient start to decay at a fixed value of τ. Likewise, steady state is attained at a larger fixed value of τ. This time scaling is physically based upon the time required for momentum to be transferred over the entire tank volume due to turbulent diffusion, and is general for any body size, tank size, rotation rate, and acceleration rate.

Relationships between silicic plutonism and volcanism: geochemical evidence

1988 ◽  
Vol 79 (2-3) ◽  
pp. 257-263 ◽  
Author(s):  
R. Macdonald ◽  
R. L. Smith
Keyword(s):  
Open Systems ◽  
Mafic Magma ◽  
Geochemical Data ◽  
Magma Chambers ◽  
Magma Body ◽  
Jemez Mountains ◽  
Evolutionary Phase ◽  
Ring Complexes ◽  
High Level ◽  
Melt Evolution

ABSTRACTField associations (voluminous ash flow deposits, rhyolitic stocks and dykes, ring complexes), evidence of repeated influxes of mafic magma, and thermal constraints indicate that many high-level silicic plutons (magma chambers) acted as open systems for considerable parts of their history. The long thermal lifetime, as well as other evidence from the volcanic record, suggests that some such systems reached a quasi-steady state in which magma input was balanced by magma output for times longer than those required for crystallisation. Reconstruction of the evolution of large, long-lived caldera-forming systems, such as that of the Jemez Mountains, New Mexico, indicates that many chambers have lost a highly fractionated silicic cap, in some cases cyclically. Crystallised plutons may contain no obvious record of this evolutionary phase.Geochemical data from silicic ash flow deposits can be used to reconstruct the volcanic stage of pluton development. Many silicic systems, especially of alkaline affinity, apparently pass from a stage in which melt evolution is dominated by crystal-liquid processes to one in which other processes may also contribute to differentiation. Apparently, the transition is most readily achieved in volatile-rich, alkaline silicic systems emplaced in complex, ancient sialic crust of the cratons. Once established, the preservation of highly fractionated caps on magma chambers requires a balance between thermal input and cooling-induced crystallisation. If heat enters the system too quickly, the cap may get stirred into the dominant magma volume by convection. If heat input is too slow, the magma body will crystallise inward from the margins, and the plutonic-consolidation stage will begin.

scholarly journals SUMMIT METABOLISM OF NEWBORN CALVES WITH AND WITHOUT COLOSTRUM FEEDING

1986 ◽  
Vol 66 (4) ◽  
pp. 937-944 ◽  
Author(s):  
M. OKAMOTO ◽  
J. B. ROBINSON ◽  
R. J. CHRISTOPHERSON ◽  
B. A. YOUNG
Keyword(s):  
Body Weight ◽  
Metabolic Rate ◽  
Rectal Temperature ◽  
Cold Water ◽  
Water Immersion ◽  
Resting Metabolic Rate ◽  
The Body ◽  
Metabolic Rates ◽  
Colostrum Feeding ◽  
Time Required

Resting and summit metabolic rates were measured in 13 newborn (2.5–15 h old) male Holstein calves exposed to warm and cold tempertures in a water immersion system. Six calves were bottle fed 1 kg of colostrum 30 min before the measurements commenced. In the remaining seven calves, colostrum was withheld until after the end of the measurement period. There were no significant effects of colostrum feeding on resting or summit metabolic rates or the time required for rectal temperature to drop to 35 °C when the calves were immersed in cold water. The time required for rectal temperature to drop to 35 °C increased as the body weight of the calves increased; for each kilogram additional body weight, cooling was delayed for an extra 2.9 min. The resting metabolic rate averaged for both feeding treatments was 2.0 ± 0.1 W kg−1 while mean rectal temperature was 39.1 ± 0.2 °C. Mean summit metabolic rate was 7.2 ± 0.4 W kg−1 and occurred at a mean rectal temperature of 35.4 ± 0.3 °C. The average ratio of the summit to resting metabolic rate was 3.7 ± 0.2. Cooling via water immersion was associated with increases in plasma levels of glucose and free fatty acids. The feeding of 1 kg of colostrum 30 min prior to exposure to acute cold did not improve the apparent resistance of the calves to hypothermia. Key words: Newborn calf, summit metabolism, cold tolerance

Pluton emplacement in arcs: a crustal-scale exchange process

1996 ◽  
Vol 87 (1-2) ◽  
pp. 115-123 ◽  
Author(s):  
Scott R. Paterson ◽  
T. Kenneth Fowler ◽  
Robert B. Miller
Keyword(s):  
Country Rock ◽  
Exchange Process ◽  
Horizontal Displacement ◽  
Magma Ascent ◽  
Driving Mechanism ◽  
Magma Chambers ◽  
Compositional Zoning ◽  
Magma Body ◽  
Regional Deformation ◽  
Multiple Pulses

ABSTRACT:Buddington (1959) pointed out that the construction of large crustal magma chambers involves complex internal processes as well as multiple country rock material transfer processes (MTPs), which reflect large horizontal, vertical and temporal gradients in physical conditions. Thus, we have attempted to determine the relative importance of different magmatic and country rock MTPs at various crustal depths, and whether country rock MTPs largely transport material vertically or horizontally, rather than seeking a single model of magma ascent and emplacement.Partially preserved roofs of nine plutons and in some cases roof–wall transitions with roof emplacement depths of 1·5–11 km were mapped. During emplacement, these roofs were not deformed in a ductile manner, detached or extended by faults, or significantly uplifted. Instead, sharp, irregular, discordant contacts are the rule with stoped blocks often preserved immediately below the roof, even at depths of 10 km. The upper portions of these magma chambers are varied, sometimes preserving the crests of more evolved magmas or local zones of volatile-rich phases and complex zones of dyking and magma mingling. Magmatic structures near roofs display a wide variety of patterns and generally formed after emplacement. Transitions from gently dipping roofs to steep walls are abrupt. At shallow crustal levels, steep wall contacts have sharp, discordant, stepped patterns with locally preserved stoped blocks indicating that the chamber grew sideways in part by stoping. Around deeper plutons, an abrupt transition (sometimes within hundreds of metres) occurs in the country rock from discordant, brittle roofs to moderately concordant, walls deformed in a ductile manner defining narrow structural aureoles. Brittle or ductile faults are not present at roof–wall joins.Near steep wall contacts at shallow to mid-crustal depths (5–15 km), vertical and horizontal deflections of pre-emplacement markers (e.g. bedding, faults, dykes), and ductile strains in narrow aureoles (0·1–0·3 body radii) give a complete range of bulk strain values that account for 0–100% of the needed space, but average around 30%, or less, particularly for larger batholiths. A lack of far-field deflection of these same markers rules out significant horizontal displacement outside the aureoles and requires that any near-field lateral shortening is accommodated by vertical flow. Lateral variations from ductile (inner aureole) to brittle (outer aureole) MTPs are typically observed. Compositional zoning is widespread within these magma bodies and is thought to represent separately evolved pulses that travelled up the same magma plumbing system. Magmatic foliations and lineations commonly cross-cut contacts between pulses and reflect the strain caused either by the late flow of melt or regional deformation.Country rocks near the few examined mid- to deep crustal walls (10–30 km) are extensively deformed, with both discordant and concordant contacts present; however, the distinction between regional and emplacement-related deformation is less clear than for shallower plutons. Internal sheeting is more common, although elliptical masses are present. Lateral compositional variations are as large as vertical variations at shallower depths and occur over shorter distances. Magmatic foliations and lineations often reflect regional deformation rather than emplacement processes.The lack of evidence for horizontal displacement outside the narrow, shallow to mid-crustal aureoles and the lack of lateral or upwards displacement of pluton roofs indicate that during emplacement most country rock is transported downwards in the region now occupied by the magma body and its aureole. The internal sheeting and zoning indicate that during the downwards flow of country rock, multiple pulses of magma travelled up the same magma system. If these relationships are widespread in arcs, magma emplacement is the driving mechanism for a huge crustal-scale exchange process.

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