Academic literature on the topic 'Time reversal. Protons'
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Journal articles on the topic "Time reversal. Protons"
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Khalil, Ali E. "Time violating amplitudes in the (3He, p) reactions." Canadian Journal of Physics 66, no. 7 (July 1, 1988): 612–17. http://dx.doi.org/10.1139/p88-101.
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The difference between the polarization (P) of protons in the reaction (3He, [Formula: see text]) and the analyzing power (A) in the inverse reaction ([Formula: see text], 3He) has been calculated using a spin-independent isospin-independent, time reversal violating interaction in the form [α(r)[Formula: see text] + Hermitian conjugate]. The interaction strength is adjusted to be 1% of the time conserving optical potentials. A distorted-wave Born approximation (DWBA) calculation assuming a direct reaction mechanism has been performed. The relative values of the time violating amplitudes have no signatures for any measurable time violating effects.
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Wang, X., and J. D. Horisberger. "A conformation of Na(+)-K+ pump is permeable to proton." American Journal of Physiology-Cell Physiology 268, no. 3 (March 1, 1995): C590—C595. http://dx.doi.org/10.1152/ajpcell.1995.268.3.c590.
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The Na(+)-K+ pump is thought to operate through a two-conformation (E1-E2) transport cycle in which the cation binding sites are accessible only from one side at a time. Using Na(+)-loaded Xenopus oocytes in which Na(+)-K+ pumps were overexpressed by injection of cRNA of the Xenopus Na(+)-K+ pump alpha-and beta-sub units, we observed a Na(+)-K+ pump-mediated (ouabain-sensitive) inward current in the absence of other transportable cations, except H+, in the external solution. This inward current was strongly inwardly rectifying, pH dependent, and larger at acid pH. Under conditions favoring a large ouabain-sensitive inward current, we observed a ouabain-sensitive intracellular acidification, and the amplitude of the acidification was significantly related to the ouabain-sensitive current, indicating that this current was carried by protons. The reversal potential of the ouabain-sensitive current was dependent on external pH as expected for a proton-conductive pathway. We conclude that in the absence of external K+ the Na(+)-K+ pump can mediate a large inward electrogenic transport of proton. This is most easily explained by the hypothesis that the E2 conformation of the Na(+)-K+ pump with cation binding sites exposed to the outside is accessible to protons from both sides and thus provides a channellike pathway for protons.
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McDonald, A. B. "Nuclear tests of fundamental interactions." Canadian Journal of Physics 67, no. 8 (August 1, 1989): 785–91. http://dx.doi.org/10.1139/p89-136.
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Measurements of parity violation in nuclei can determine properties of the basic weak nucleon–nucleon interaction, thereby testing electroweak theory and quark models of nucleons. Experiments observing parity violation in the photodisintegration of deuterium, in the scattering of protons from hydrogen, and in the emission of circularly polarized γ rays from 18F are described. A new technique for polarizing 3He is described, and the use of polarized 3He in measurements of parity and time reversal violation is presented. Finally, new directions in γ-ray spectroscopy are illustrated by the Sudbury Neutrino Observatory and new ultrahigh resolution bolometric detectors.
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Heber, B., G. Sarri, G. Wibberenz, C. Paizis, P. Ferrando, A. Raviart, A. Posner, R. Müller-Mellin, and H. Kunow. "The Ulysses fast latitude scans: COSPIN/KET results." Annales Geophysicae 21, no. 6 (June 30, 2003): 1275–88. http://dx.doi.org/10.5194/angeo-21-1275-2003.
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Abstract. Ulysses, launched in October 1990, began its second out-of-ecliptic orbit in December 1997, and its second fast latitude scan in September 2000. In contrast to the first fast latitude scan in 1994/1995, during the second fast latitude scan solar activity was close to maximum. The solar magnetic field reversed its polarity around July 2000. While the first latitude scan mainly gave a snapshot of the spatial distribution of galactic cosmic rays, the second one is dominated by temporal variations. Solar particle increases are observed at all heliographic latitudes, including events that produce >250 MeV protons and 50 MeV electrons. Using observations from the University of Chicago’s instrument on board IMP8 at Earth, we find that most solar particle events are observed at both high and low latitudes, indicating either acceleration of these particles over a broad latitude range or an efficient latitudinal transport. The latter is supported by "quiet time" variations in the MeV electron background, if interpreted as Jovian electrons. No latitudinal gradient was found for >106 MeV galactic cosmic ray protons, during the solar maximum fast latitude scan. The electron to proton ratio remains constant and has practically the same value as in the previous solar maximum. Both results indicate that drift is of minor importance. It was expected that, with the reversal of the solar magnetic field and in the declining phase of the solar cycle, this ratio should increase. This was, however, not observed, probably because the transition to the new magnetic cycle was not completely terminated within the heliosphere, as indicated by the Ulysses magnetic field and solar wind measurements. We argue that the new A<0-solar magnetic modulation epoch will establish itself once both polar coronal holes have developed.Key words. Interplanetary physics (cosmic rays; energetic particles; interplanetary magnetic fields)
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Sánchez, C. M., P. R. Levstein, L. Buljubasich, H. M. Pastawski, and A. K. Chattah. "Quantum dynamics of excitations and decoherence in many-spin systems detected with Loschmidt echoes: its relation to their spreading through the Hilbert space." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 374, no. 2069 (June 13, 2016): 20150155. http://dx.doi.org/10.1098/rsta.2015.0155.
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In this work, we overview time-reversal nuclear magnetic resonance (NMR) experiments in many-spin systems evolving under the dipolar Hamiltonian. The Loschmidt echo (LE) in NMR is the signal of excitations which, after evolving with a forward Hamiltonian, is recovered by means of a backward evolution. The presence of non-diagonal terms in the non-equilibrium density matrix of the many-body state is directly monitored experimentally by encoding the multiple quantum coherences. This enables a spin counting procedure, giving information on the spreading of an excitation through the Hilbert space and the formation of clusters of correlated spins. Two samples representing different spin systems with coupled networks were used in the experiments. Protons in polycrystalline ferrocene correspond to an ‘infinite’ network. By contrast, the liquid crystal N -(4-methoxybenzylidene)-4-butylaniline in the nematic mesophase represents a finite proton system with a hierarchical set of couplings. A close connection was established between the LE decay and the spin counting measurements, confirming the hypothesis that the complexity of the system is driven by the coherent dynamics.
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MURILLO, Isabel, and Lydia M. HENDERSON. "Expression of gp91phox/Nox2 in COS-7 cells: cellular localization of the protein and the detection of outward proton currents." Biochemical Journal 385, no. 3 (January 24, 2005): 649–57. http://dx.doi.org/10.1042/bj20040829.
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We have reported previously that gp91phox, expressed in CHO (Chinese hamster ovary) cells, functions as a voltage-dependent proton channel. However, others have reported that COS-7 cells expressing gp91phox failed to exhibit outward proton currents, and concluded that gp91phox does not function as a proton channel. To investigate this clear difference in findings, we have examined the expression and cellular localization of the fusion protein EGFP-C–91, in which gp91phox is fused to the C-terminus of enhanced green fluorescent protein. EGFP-C–91 was observed in the plasma membrane and intracellular membranes of 30% of the transfected COS-7 cells. In the remaining COS-7 cells, EGFP-C–91 was detected in the intracellular membranes only. In CHO cells EGFP-C–91 was present in both the plasma membrane and the intracellular membranes of all transfected cells. Under the whole-cell configuration, outward currents were recorded from COS-7 cells expressing gp91phox. These increased in magnitude and lost their ‘droop’ over time as the pipette solution equilibrated with the cell cytoplasm (50 min). The threshold activation voltage for the currents was shifted by ∼60 mV for a 1 unit difference in bath pH. Zn2+ inhibited the outward currents observed in COS-7 cells expressing gp91phox. The tail current reversal potential was −64 mV at a pHo (external pH) of 8.0, −40 mV at pHo 7.4 and −8 mV at pHo 7.0, indicating that the current arises from the movement of protons. Outward currents were exhibited by 37.5% of the COS-7 cells expressing gp91phox. Proton currents were recorded following the excision of inside-out patches from cells transfected with gp91phox. The presence of outward proton currents in COS-7 cells expressing gp91phox provides further support for our proposed role for gp91phox as the NADPH oxidase-associated proton channel.
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Belov, A. V., E. A. Eroshenko, B. Heber, V. G. Yanke, A. Raviart, R. Müller-Mellin, and H. Kunow. "Latitudinal and radial variation of >2 GeV/n protons and alpha-particles at solar maximum: ULYSSES COSPIN/KET and neutron monitor network observations." Annales Geophysicae 21, no. 6 (June 30, 2003): 1295–302. http://dx.doi.org/10.5194/angeo-21-1295-2003.
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Abstract. Ulysses, launched in October 1990, began its second out-of-ecliptic orbit in September 1997. In 2000/2001 the spacecraft passed from the south to the north polar regions of the Sun in the inner heliosphere. In contrast to the first rapid pole to pole passage in 1994/1995 close to solar minimum, Ulysses experiences now solar maximum conditions. The Kiel Electron Telescope (KET) measures also protons and alpha-particles in the energy range from 5 MeV/n to >2 GeV/n. To derive radial and latitudinal gradients for >2 GeV/n protons and alpha-particles, data from the Chicago instrument on board IMP-8 and the neutron monitor network have been used to determine the corresponding time profiles at Earth. We obtain a spatial distribution at solar maximum which differs greatly from the solar minimum distribution. A steady-state approximation, which was characterized by a small radial and significant latitudinal gradient at solar minimum, was interchanged with a highly variable one with a large radial and a small – consistent with zero – latitudinal gradient. A significant deviation from a spherically symmetric cosmic ray distribution following the reversal of the solar magnetic field in 2000/2001 has not been observed yet. A small deviation has only been observed at northern polar regions, showing an excess of particles instead of the expected depression. This indicates that the reconfiguration of the heliospheric magnetic field, caused by the reappearance of the northern polar coronal hole, starts dominating the modulation of galactic cosmic rays already at solar maximum.Key words. Interplanetary physics (cosmic rays; energetic particles) – Space plasma physics (charged particle motion and acceleration)
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Burbidge, G. "Explosive Cosmogony and the Quasi-Steady State Cosmology." Symposium - International Astronomical Union 183 (1999): 286–89. http://dx.doi.org/10.1017/s0074180900132954.
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Modern cosmology began with the realization that there were solutions to Einstein's theory of gravity discovered by Friedmann and Lemaitre which when combined with the redshift distance relation of Hubble and others could be interpreted as showing that we live in an expanding universe. By 1930, the scientific establishment and many of the lay public believed this. It was then only elementary logic to argue that if time reversal was applied, the universe must originally have been so compact that we could talk of a beginning. Lemaitre tried to describe this state as the “Primeval Atom.” For a decade or so after the war, Gamow, Alpher and Herman and other leading physicists explored this dense configuration trying to make the chemical elements from protons and neutrons. They soon learned that this was not possible because of the absence of stable masses of five and eight, but they also realized that if such an early stage had occurred the universe would contain an expanding cloud of radiation which would preserve its black body form. Dicke and his colleagues in Princeton rediscovered this idea and decided to try and detect the radiation. Penzias and Wilson found such a radiation field, and COBE has demonstrated that it has a perfect black body form out to radio wavelengths. This history of the discovery together with the fact that the light elements D, He3 and He4 in about the right amounts can be made in a hot big bang has led to the widely held, but simplistic view, that the standard cosmology - the hot big bang - is correct.
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Coady, Michael J., Bernadette Wallendorff, and Jean-Yves Lapointe. "Characterization of the transport activity of SGLT2/MAP17, the renal low-affinity Na+-glucose cotransporter." American Journal of Physiology-Renal Physiology 313, no. 2 (August 1, 2017): F467—F474. http://dx.doi.org/10.1152/ajprenal.00628.2016.
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The cotransporter SGLT2 is responsible for 90% of renal glucose reabsorption, and we recently showed that MAP17 appears to work as a required β-subunit. We report in the present study a detailed functional characterization of human SGLT2 in coexpression with human MAP17 in Xenopus laevis oocytes. Addition of external glucose generates a large inward current in the presence of Na, confirming an electrogenic transport mechanism. At a membrane potential of −50 mV, SGLT2 affinity constants for glucose and Na are 3.4 ± 0.4 and 18 ± 6 mM, respectively. The change in the reversal potential of the cotransport current as a function of external glucose concentration clearly confirms a 1:1 Na-to-glucose transport stoichiometry. SGLT2 is selective for glucose and α-methylglucose but also transports, to a lesser extent, galactose and 3- O-methylglucose. SGLT2 can be inhibited in a competitive manner by phlorizin ( Ki = 31 ± 4 nM) and by dapagliflozin ( Ki = 0.75 ± 0.3 nM). Similarly to SGLT1, SGLT2 can be activated by Na, Li, and protons. Pre-steady-state currents for SGLT2 do exist but are small in amplitude and relatively fast (a time constant of ~2 ms). The leak current defined as the phlorizin-sensitive current in the absence of substrate was extremely small in the case of SGLT2. In summary, in comparison with SGLT1, SGLT2 has a lower affinity for glucose, a transport stoichiometry of 1:1, very small pre-steady-state and leak currents, a 10-fold higher affinity for phlorizin, and an affinity for dapagliflozin in the subnanomolar range.
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Nan, Beiyan, Jigar N. Bandaria, Kathy Y. Guo, Xue Fan, Amirpasha Moghtaderi, Ahmet Yildiz, and David R. Zusman. "The polarity of myxobacterial gliding is regulated by direct interactions between the gliding motors and the Ras homolog MglA." Proceedings of the National Academy of Sciences 112, no. 2 (December 30, 2014): E186—E193. http://dx.doi.org/10.1073/pnas.1421073112.
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Gliding motility in Myxococcus xanthus is powered by flagella stator homologs that move in helical trajectories using proton motive force. The Frz chemosensory pathway regulates the cell polarity axis through MglA, a Ras family GTPase; however, little is known about how MglA establishes the polarity of gliding, because the gliding motors move simultaneously in opposite directions. Here we examined the localization and dynamics of MglA and gliding motors in high spatial and time resolution. We determined that MglA localizes not only at the cell poles, but also along the cell bodies, forming a decreasing concentration gradient toward the lagging cell pole. MglA directly interacts with the motor protein AglR, and the spatial distribution of AglR reversals is positively correlated with the MglA gradient. Thus, the motors moving toward lagging cell poles are less likely to reverse, generating stronger forward propulsion. MglB, the GTPase-activating protein of MglA, regulates motor reversal by maintaining the MglA gradient. Our results suggest a mechanism whereby bacteria use Ras family proteins to modulate cellular polarity.
Dissertations / Theses on the topic "Time reversal. Protons"
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Caviness, James A. "Stress biomarkers in a rat model of decompression sickness /." Download the thesis in PDF, 2005. http://www.lrc.usuhs.mil/dissertations/pdf/Caviness2005.pdf/.
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王辰文. "Ground-state Proton Transfer Dynamics of HPTS in AOT Reverse Micelles as Studied by Nanosecond Time-Resolved Infrared Spectroscopy." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/94548666759372290853.
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碩士國立交通大學
應用化學系分子科學碩博士班
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1-hydroxy-3,6,8-pyrenetrisulphonic acid (commonly referred to as HPTS) is one of the most extensively studied fluorescent molecules. HPTS occurs as two forms in aqueous solution. One is the acidic form, whose absorption maximum is located at ~400 nm, and the other is the basic form, which has the absorption maximum at ~450 nm. The pKa of HPTS in the electronic ground state is about 7.2, whereas that in the first excited state drastically decreases to 0.5. Being motivated by this phototriggered change in acidity, a number of studies have been done to understand the proton transfer dynamics of HPTS in the excited state. However, most of those studies used electronic absorption and/or emission spectroscopies. Vibrational spectroscopic studies, which provide more direct information on the structure of the two forms of HPTS, are still scant. Here, we apply nanosecond time-resolved infrared (TRIR) spectroscopy to investigate the proton transfer dynamics of HPTS in the ground state. To be able to perform TRIR measurements in aqueous solution, we utilize the nanoscale water pool of reverse micelles formed by bis(2-ethylhexyl) sulfosuccinate (known as AOT), in which HPTS is dissolved. The use of reverse micelles allows us not only to effectively decrease the immense IR absorption of water but also to control the microscopic environment of HPTS from confined water to bulk-like water by varying the water-to-surfactant ratio, W0 = [H2O]/[AOT]. Transient IR spectra of HPTS in AOT reverse micelles excited at 355 nm are recorded in the sub-?酲 to ?酨 time regime. The average number of HPTS molecules in a single reverse micelle is adjusted to 0.8 so that no more than one HPTS molecule is included on average. It is shown that the observed dynamics is attributed to the reprotonation process of the basic form of HPTS in the ground state. We measure the decay profiles of the transient species with varying the W0 value from 7 to 25, which are fit to an exponential function. The exponential time constant,?n??z so determined changes drastically depending on W0: that is, ??n= 0.2 ?酨 at W0 = 7, whereas ? = 2.4 ?酨 at W0 = 25. In other words, the reprotonation rate of HPTS increases as the water pool size decreases. This result is in qualitative agreement with a diffusion model of the back proton-transfer of HPTS in the ground state. We also find that the decay profile depends on the average number of HPTS molecules present in the water pool of AOT reverse micelles.
Books on the topic "Time reversal. Protons"
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Grant, Warren, and Martin Scott-Brown. Principles of oncogenesis. Edited by Patrick Davey and David Sprigings. Oxford University Press, 2018. http://dx.doi.org/10.1093/med/9780199568741.003.0322.
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It is obvious that the process of developing cancer—oncogenesis—is a multistep process. We know that smoking, obesity, and a family history are strong independent predictors of developing malignancy; yet, in clinics, we often see that some heavy smokers live into their nineties and that some people with close relatives affected by cancer spend many years worrying about a disease that, in the end, they never contract. For many centuries scientists have struggled to understand the process that make cancer cells different from normal cells. There were those in ancient times who believed that tumours were attributable to acts of the gods. Hippocrates suggested that cancer resulted from an imbalance between the black humour that came from the spleen, and the other three humours: blood, phlegm, and bile. It is only in the last 100 years that biologists have been able to characterize some of the pathways that lead to the uncontrolled replication seen in cancer, and subsequently examine exactly how these pathways evolve. The rampant nature by which cancer invades local and distant tissues, as well its apparent ability to spread between related individuals led some, such as Peyton Rous in 1910, to suggest that cancer was an infectious condition. He was awarded a Nobel Prize in 1966 for the 50 years of work into investigating a link between sarcoma in chickens and a retrovirus that became known as Rous sarcoma virus. He had shown how retroviruses are able to integrate sequences of DNA coding for errors in cellular replication control (oncogenes) by introducing into the human cell viral RNA together with a reverse transcriptase. Viruses are now implicated in many cancers, and in countries where viruses such as HIV and EBV are endemic, the high incidence of malignancies such as Kaposi’s sarcoma and Burkitt’s lymphoma is likely to be directly related. There are several families of viruses associated with cancer, broadly classed into DNA viruses, which mutate human genes using their own DNA, and retroviruses, like Rous sarcoma virus, which insert viral RNA into the cell, where it is then transcribed into genes. This link with viruses has not only led to an understanding that cancer originates from genetic mutations, but has also become a key focus in the design of new anticancer therapies. Traditional chemotherapies either alter DNA structure (as with cisplatin) or inhibit production of its component parts (as with 5-fluorouracil.) These broad-spectrum agents have many and varied side effects, largely due to their non-specific activity on replicating DNA throughout the body, not just in tumour cells. New vaccine therapies utilizing gene-coding viruses aim to restore deficient biological pathways or inhibit mutated ones specific to tumour cells. The hope is that these gene therapies will be effective and easily tolerated by patients, but development is currently progressing with caution. In a trial in France of ten children suffering from X-linked severe combined immunodeficiency and who were injected with a vector that coded for the gene product they lacked, two of the children subsequently died from leukaemia. Further analysis confirmed that the DNA from the viral vector had become integrated into an existing, but normally inactive, proto-oncogene, LM02, triggering its conversion into an active oncogene, and the development of life-threatening malignancy. To understand how a tiny change in genetic structure could lead to such tragic consequences, we need to understand the molecular biology of the cell and, in particular, to pay attention to the pathways of growth regulation that are necessary in all mammalian cell populations. Errors in six key regulatory pathways are known as the ‘hallmarks of cancer’ and will be discussed in the rest of this chapter.
Book chapters on the topic "Time reversal. Protons"
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Shalev, Idan, and Waylon J. Hastings. "Psychosocial stress and telomere regulation." In Genes, brain, and emotions, 247–61. Oxford University Press, 2019. http://dx.doi.org/10.1093/oso/9780198793014.003.0017.
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Telomeres, the repetitive nucleoprotein regions at chromosome ends, are hallmarks of biological aging. Deficiencies in the network of proteins and nucleic acids which govern telomere regulation result in their gradual erosion over time, and shorter telomere length is associated with chronic disease as well as all-cause mortality. Telomeres are also indicative of cumulative stress experienced across the lifespan. This chapter summarizes empirical evidence for the impact of lifelong psychosocial stress, lifestyle behaviors, and chronic diseases on telomere biology. This biological embedding of experiences involves complex interactions with cellular processes regulating telomere length. Before describing such interactions, the chapter chronicles intrinsic regulation of telomeres by enzymatic, RNA, and epigenetic mechanisms. It then considers the stress-related mechanisms implicated in telomere regulation, including neuroendocrine systems, immuno-inflammation, oxidative stress, and mitochondrial respiration. A full understanding of these processes can promote better clinical treatments and intervention efforts to reverse the damaging effect of stress on telomeres.
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Sullivan, Raymond, Morgan D. Sullivan, Stephen W. Edwards, Andrei M. Sarna-Wojcicki, Rebecca A. Hackworth, and Alan L. Deino. "Mid-Cenozoic succession on the northeast limb of the Mount Diablo anticline, California—A stratigraphic record of tectonic events in the forearc basin." In Regional Geology of Mount Diablo, California: Its Tectonic Evolution on the North America Plate Boundary. Geological Society of America, 2021. http://dx.doi.org/10.1130/2021.1217(13).
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ABSTRACT The mid-Cenozoic succession in the northeast limb of the Mount Diablo anticline records the evolution of plate interactions at the leading edge of the North America plate. Subduction of the Kula plate and later Farallon plate beneath the North America plate created a marine forearc basin that existed from late Mesozoic to mid-Cenozoic times. In the early Cenozoic, extension on north-south faults formed a graben depocenter on the west side of the basin. Deposition of the Markley Formation of middle to late? Eocene age took place in the late stages of the marine forearc basin. In the Oligocene, the marine forearc basin changed to a primarily nonmarine basin, and the depocenter of the basin shifted eastward of the Midland fault to a south-central location for the remainder of the Cenozoic. The causes of these changes may have included slowing in the rate of subduction, resulting in slowing subsidence, and they might also have been related to the initiation of transform motion far to the south. Two unconformities in the mid-Cenozoic succession record the changing events on the plate boundary. The first hiatus is between the Markley Formation and the overlying Kirker Formation of Oligocene age. The succession above the unconformity records the widespread appearance of nonmarine rocks and the first abundant appearance of silicic volcanic detritus due to slab rollback, which reversed the northeastward migration of the volcanic arc to a more proximal location. A second regional unconformity separates the Kirker/Valley Springs formations from the overlying Cierbo/Mehrten formations of late Miocene age. This late Miocene unconformity may reflect readjustment of stresses in the North America plate that occurred when subduction was replaced by transform motion at the plate boundary. The Cierbo and Neroly formations above the unconformity contain abundant andesitic detritus due to proto-Cascade volcanism. In the late Cenozoic, the northward-migrating triple junction produced volcanic eruptive centers in the Coast Ranges. Tephra from these local sources produced time markers in the late Cenozoic succession.
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Clark, Gregory O., and William J. Kovacs. "Glucose, Lipid, and Protein Metabolism." In Textbook of Endocrine Physiology. Oxford University Press, 2011. http://dx.doi.org/10.1093/oso/9780199744121.003.0018.
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The maintenance of life requires a constant supply of substrate for the generation of energy and preservation of the structure of cells and tissues. The process in principle is simple, yet the individual metabolic pathways and the regulation of substrate fluxes through these pathways can be complex. Energy is derived when fuel substrates are oxidized to carbon dioxide and water in the presence of oxygen, generating adenosine triphosphate (ATP). A portion of the ingested foodstuff is also utilized, either directly or after transformation into other substrates, to repair and replace cell membranes, structural proteins, and organelles. The remainder is stored as potential energy in the form of glycogen or fat. Under normal circumstances, each individual remains in a near-steady state where weight and appearance are stable over prolonged periods. In the short term, fuel metabolism changes dramatically several times a day during alternating periods of feeding and fasting. An anabolic phase begins with food ingestion and lasts for several hours. Energy storage occurs during this period when caloric intake exceeds caloric demands. The catabolic phase usually begins 4 to 6 hours after a meal and lasts until the person eats once again. During this phase, utilization shifts from exogenous to endogenous fuels, a change heralded by the mobilization of substrate stored in liver, muscle, and adipose tissue. Both anabolic and catabolic phases are characterized by specific biochemical processes regulated by distinct hormonal profiles. In the anabolic phase that follows ingestion of a mixed meal, substrate flux is directed from the intestine through the liver to storage and utilization sites. Glucose, triglyceride, and amino acid concentrations increase in plasma, whereas those of fatty acids, ketones (acetoacetic and β -hydroxy-butyric acids), and glycerol decrease. Both glycogen and protein synthesis begin in liver and muscle, while fatty acid synthesis and triglyceride esterification are stimulated in hepatocytes and adipose tissue. In the catabolic phase, the biochemical activities are reversed and the flux of fuel is directed from storage depots to liver and other utilization sites.
Conference papers on the topic "Time reversal. Protons"
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Eversheim, P. D., F. Hinterberger, J. Bisplinghoff, R. Jahn, J. Ernst, W. Kretschmer, H. Paetz gen. Schieck, and H. E. Conzett. "Test of time-reversal invariance in proton-deuteron scattering." In The 8th International symposium on polarization phenomena in nuclear physics. AIP, 1995. http://dx.doi.org/10.1063/1.48678.
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Stoicescu, Ramona, Razvan-Alexandru Stoicescu, Codrin Gheorghe, Adina Honcea, and Iulian Bratu. "CONSIDERATIONS ON SARS-COV-2 DIAGNOSIS IN THE LABORATORY OF UNIVERSITY EMERGENCY CLINICAL HOSPITAL OF CONSTANTA." In GEOLINKS Conference Proceedings. Saima Consult Ltd, 2021. http://dx.doi.org/10.32008/geolinks2021/b1/v3/07.
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Coronaviruses are members of the Coronaviridae family. They are enveloped, non-segmented, positive-sense, single-stranded RNA viruses. Their genome size is about 30 kilobases (kb) which consist, at the 5’ end, of non-structural open reading frames (ORFs: ORF1a, ORF 1b) which code for 16 non structural proteins, and at the 3’ end the genes which code for four structural proteins including membrane (M), envelope (E), spike (S), and nucleocapsid (N) proteins. Due to the rapid spread of COVID-19, a reliable detection method is needed for patient diagnosis especially in the early stages of the disease. WHO has recommended nucleic acid amplification tests such as real-time reverse transcription-polymerase chain reaction (RT-PCR). The assay detects three SARS-CoV-2 RNA targets: the envelope (E) gene, the nucleocapsid (N) gene and a region of the open reading frame (ORF1) of the RNA-dependent RNA polymerase (RdRp) gene from SARS-CoV-2 virus isolate Wuhan-Hu-1. Our study was made in the first 3 months of the year 2021 using the real-time RT PCR results obtained in the Cellular Biology ward of the University Emergency Clinical Hospital. In our lab we are testing the inpatients from the hospital wards (Neurology, Pediatrics, Surgery, Internal medicine, ICU, Cardiology, etc.); we are also testing the outpatients from Dialysis and Oncology, 2 days prior to their therapy; we also test the health care personnel. The number of tests we performed was: in January 1456, with 399 positive results (27.4%), 33 deaths; in February 1273 tests, 221 positive (17.36%), 16 deaths; in March 1471 tests, 373 positive (25.36%), 37 deceased.
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Johannessen, M., F. E. Nielsen, K. Pingel, and L. C. Petersen. "FIBRINOLYTIC EFFECT OF ONE-CHAIN TTSSUE-TYPE PLASMINOGEN ACTIVATOR." In XIth International Congress on Thrombosis and Haemostasis. Schattauer GmbH, 1987. http://dx.doi.org/10.1055/s-0038-1644406.
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The fibrinolytic properties of authentic one- and two-chain recombinant tPA were compared to those of a plasmin resistant one-chain tPA analogue, tPA-Gly275, which is point mutated in Arg275 of the activation site. The proteins were characterised by reversed phase HPLC, reduced SDS-PAGE, and their concentrations determined by the BCA (modified Lowry) method. When equivalent conc. of these enzymes were tested for fibrinolytic activity by means of clot lysis and fibrin plate lysis methods, the values found for two-chain tPA were consistently 50% higher than one-chain tPA forms. The time course for plasmin catalysed one-chain tPA cleavage during fibrin clot lysis was determined by means of 125I-tPA. The cleavage is not instantaneous, and one-chain tPA may account for a considerable fraction of the total amount of plasmin formed. This is confirmed by similar experiments with 125I-tPA-Gly275, which is essentially intact one-chain tPA at the time of fibrin clot lysis. The effect of tPA activation site cleavage was also studied using plasmin coupled to sepharose beads. Plasmin sepharose was removed at different time intervals, and tPA was tested for amidolytic activity with > Glu-Gly-Arg-pNA and fibrinolytic activity as measured by fibrin clot lysis time as well as by fibrin plate methods. The results indicate that in the presence of fibrin, plasminogen can be activated by one-chain tPA at a considerable rate. On the other hand, the fact that the fibrinolytic activity measured by conventional assays is lower with one-chain tPA than with two-chain tPA should be considered when of these methods are used for standardization.