Artículos de revistas: "Plateau"

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Lin, Yi-chun, Angela Shin-yih Chen y Yu-ting Lai. "Breach or bridge your career? Understanding the relationship between career plateau and internal employability". Personnel Review 47, n.º 5 (6 de agosto de 2018): 986–1002. http://dx.doi.org/10.1108/pr-04-2017-0101.

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Purpose The purpose of this paper is to identify the impact of career plateau (hierarchical and job-content plateau) on internal employability, and to investigate psychological contract breach as a moderator on the relationship between career plateau (hierarchical and job-content plateau) and internal employability. Design/methodology/approach Data were collected by distributing paper-based questionnaires to 521 workers in private banking sectors in Taiwan. Hierarchical regression analysis was used to examine the results of the relationships. Findings The results supported the idea that career plateau (hierarchical and job-content plateaus) could be a significant antecedent of internal employability. Psychological contract breach significantly moderated the negative relationship between career plateau (hierarchical and job-content plateau) and internal employability. Specifically, the negative relationship between career plateau and internal employability will be stronger for employees who perceive a higher level of psychological contract breach. Practical implications These findings can help human resource practitioners gain a better understanding of the value of applicable approaches as an influence on a plateaued employee’s perception of internal employability, and to facilitate a positive employer–employee relationship, which could foster both a successful career for an individual and a prosperous performance for the organization that employs them. Originality/value Career plateau have been aroused variety issues in HR practice, but employability and psychological contract breach have barely been discussed with career plateau. This study empirically establishes the correlation between career plateau and internal employability as well as shown that psychological contract breach would decrease the plateaued individual’s willingness to stay in the current organization. Thus, the career plateau may provide organizations with a helpful perspective on one’s career development. Building substantial relationships between employees and employers lead to better human capital for organizations as it deals with rapidly changes in the real world.

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Zängl, Günther y Silvia Gonzalez Chico. "The Thermal Circulation of a Grand Plateau: Sensitivity to the Height, Width, and Shape of the Plateau". Monthly Weather Review 134, n.º 9 (1 de septiembre de 2006): 2581–600. http://dx.doi.org/10.1175/mwr3207.1.

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Abstract Idealized numerical simulations are presented to investigate the sensitivity of the thermal plateau circulation to the plateau height, width, and the presence of a mountain ridge encompassing the plateau. The study concentrates on plateaus surrounded by land with the same surface properties so that the topography is the only source of differential heating. For low plateaus, it is found that the strength of the plateau circulation increases with the plateau height because the excess heating of the plateau increases with its height. The plateau circulation reaches its maximum strength for plateau heights similar to the mixed-layer depth over the surrounding lowlands. For even higher plateaus, the depth of the circulation decreases whereas the peak intensity exhibits little change. The plateau height also controls the temporal evolution of the plateau circulation. For low plateaus, low-level inflow is primarily found during the night because convection cells forming over the lateral slopes prevent an inward mass flux during the day. With increasing plateau height, the phases of the plateau circulation shift toward earlier times. If the plateau height exceeds the mixed-layer depth over the surrounding lowlands, inflow occurs from afternoon until the late evening. After sunset, the inflow layer tends to assume the characteristics of a density current. The convergence of the density currents propagating from each side of the plateau toward the center helps to fill the heat low formed during the day. Moreover gravity waves are triggered that propagate away from the plateau center and terminate the inflow. The propagation speed of the density currents is found to increase with the plateau height, so that their convergence occurs earlier for high plateaus than for low plateaus. For the parameter range considered in this study, the plateau width is found to have only a minor impact on the mass fluxes associated with the plateau circulation. However, the convergence of the density currents over the plateau center occurs later for a wider plateau, implying that the heat low is more persistent. Substantial changes are obtained when the plateau is surrounded by a mountain ridge. In this case, the inflow toward the plateau gets delayed because a slope wind circulation forms over the mountain ridge. Moreover, the mass fluxes toward the plateau are reduced so that the heat low that formed over the plateau during the day is filled only slowly. As a consequence, the inflow lasts throughout the night in the presence of a high mountain ridge surrounding the plateau.

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Hochmuth, K., K. Gohl, G. Uenzelmann-Neben y R. Werner. "The diverse crustal structure and magmatic evolution of the Manihiki Plateau, central Pacific". Solid Earth Discussions 6, n.º 2 (25 de julio de 2014): 1863–905. http://dx.doi.org/10.5194/sed-6-1863-2014.

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Abstract. The Manihiki Plateau is a Large Igneous Province (LIP) in the central Pacific. It was emplaced as part of the "Super-LIP" Ontong Java Nui and experienced fragmentation into three sub-plateaus, possibly during the break-up of Ontong Java Nui. The Manihiki Plateau is presumably the centerpiece of this "Super-LIP" and its investigation can therefore decipher the break-up mechanisms as well as the evolution of the plateau after its initial emplacement. By analyzing two seismic refraction/wide-angle reflection profiles crossing the two largest sub-plateaus of the Manihiki Plateau, the High Plateau and the Western Plateaus, we give new insights into their crustal structure and magmatic evolution. The High Plateau shows a crustal structure of 20 km thickness and a seismic P wave velocity distribution, which is comparable to other LIPs. The High Plateau experienced a strong secondary volcanism, which can be seen in relicts of seamount chain volcanism. The Western Plateaus on the other hand show no extensive secondary volcanism and are mainly structured by fault systems and sedimentary basins. A constant decrease in Moho depth (9–17 km) is a further indicator of crustal stretching on the Western Plateaus. Those findings lead to the conclusion, that the two sub-plateaus of the Manihiki Plateau experienced a different magmatic and tectonic history. Whereas the High Plateau experienced a secondary volcanism, the Western Plateaus underwent crustal stretching during and after the break-up of Ontong Java Nui. This indicates, that the sub-plateaus of the Manihiki Plateau play an individual part in the break-up history of Ontong Java Nui.

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Trivedi, Bhumi Mahesh y Biju Varkkey. "Managing career plateau: case of Aster Retail, UAE". Strategic HR Review 19, n.º 5 (16 de diciembre de 2020): 243–48. http://dx.doi.org/10.1108/shr-10-2020-188.

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Purpose The purpose of this paper is to discuss how Aster Retail (AR), UAE, handled career plateau challenge by adopting multiple strategies and earning employee commitment and motivation for business growth. Design/methodology/approach The organization addressed two types of plateaus – structural and content by creating both vertical and lateral opportunities/options for employees, and supporting them with resources to build required capabilities, and managing their career aspirations. The strategies also helped AR to remain true to the organization’s philosophy, “We will treat you well.” Findings The study enunciates how HR initiatives can add value by converting the negative phenomenon of plateau, into an opportunity for employees to grow. Originality/value The study has three contributions: How in a retail organization with strong promoter principles and values, both structural and content plateau are addressed, and linked with business strategies? The study sheds light on how organizational and HR support for career management addresses employee plateau, particularly for solid citizens. makes the employees feel “not plateaued” at all; and in the long run, why and how HR managers should focus more on proactively addressing content plateau than structural plateau.

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Banks, M. S. y B. T. Backus. "Conflicts with Extraretinal and Monocular Cues Cause the Small Range of the Induced Effect". Perception 26, n.º 1_suppl (agosto de 1997): 79. http://dx.doi.org/10.1068/v970170.

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A vertical magnifier before one eye causes the induced effect: an apparent rotation of frontal surfaces toward that eye. The rotation required to restore apparent frontoparallelism grows linearly up to ∼4% magnification, but plateaus at 8%. We examined the cause of the plateau. Horizontal disparities (quantified by horizontal size ratios, HSRs) are ambiguous indicators of surface slant. Various retinal and nonretinal signals can allow veridical slant estimation from HSR, sensed eye position, vertical disparities (vertical size ratios, VSRs), and monocular cues. Vertical or horizontal magnification of one eye's image alters the natural relationships among HSR, VSR, eye position, and monocular cues. We argue that the induced-effect plateau is caused by conflicts between these means of estimating slant. A plateau is not observed in the geometric effect because some of the conflicts do not occur with horizontal magnification. Two experiments were designed to test this hypothesis. When strong monocular cues were present, plateaux occurred at ∼8% magnification in the induced, but not the geometric effect. When monocular slant cues were made useless, induced-effect plateaux were abolished. Even with strong monocular cues present, plateaux in the induced effect were eliminated when eye position was consistent with the vertical magnification in the retinal images. The smaller range of the induced effect can only be understood from consideration of all the signals involved in slant estimation.

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Nam, Ji-Hoon, Yong-Gon Koh, Paul Shinil Kim y Kyoung-Tak Kang. "Existence of Gender-Based Difference in Morphology of Convex Lateral Tibial Plateau in Korean Population Primary Knee Joint Osteoarthritis". BioMed Research International 2021 (25 de agosto de 2021): 1–5. http://dx.doi.org/10.1155/2021/6641717.

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Purpose. Morphological differences in the knee joints of females and males have been reported in a previous study. These differences have realized the need of developing a gender-specific prosthesis. However, anatomical studies on gender-based differences in the proximal tibial plateau’s sagittal curvature have rarely been conducted. Therefore, this study is aimed at evaluating the geometry of the sagittal curvature of the proximal tibial plateau in the Korean population. Methods. Three-dimensional data for the sagittal curvature of the tibial plateau morphology from 1976 patients (i.e., 299 male and 1677 female) were assessed using magnetic resonance imaging. The sagittal profiles of the tibial plateaus were also evaluated. The independent t -test and paired t -test were used for statistical analysis. Results. The proximal tibia had concave and convex surfaces in the medial and lateral plateaus, respectively, for both genders. In addition, the medial diameter of the tibial plateau was significantly greater than the lateral diameter for both genders. Gender-based difference was not found in the medial diameter of the tibial plateau but was observed in the lateral diameter. Conclusion. These results may provide guidelines for a suitable knee implant design for the Korean patients. The incorporation of this shape information in the medial and lateral sides in the prosthetics for a total knee arthroplasty and a lateral unicompartmental knee arthroplasty can improve knee range motion.

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Balmer, Sven y Michael Sarnthein. "Planktic14C Plateaus: A Result of Short-Term Sedimentation Pulses?" Radiocarbon 59, n.º 1 (14 de diciembre de 2016): 33–43. http://dx.doi.org/10.1017/rdc.2016.100.

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AbstractThe tuning of plateaus in glacial and deglacial planktic radiocarbon records to pertinent structures in the atmospheric14C record of Lake Suigetsu results in both a record of surface water reservoir ages and a centennial-scale absolute age model. However, the atmospheric origin of planktic14C plateaus may be questioned. Alternatively, plateaus may result from short pulses of increased hemipelagic sediment deposition, which challenges the technique of14C plateau tuning. To test the two rationales for the interval 23–12 cal ka, we calculated hypothetical sedimentation rates for all14C plateaus identified in five Atlantic sediment cores assuming sediment pulses that either span 10, 100, 200, or 300 yr each. These rates were compared to rates derived by14C plateau tuning that assumes an atmospheric origin of the plateaus. In each plateau suite, our hypothetical sedimentation rates result in at least one or two cases in extreme values that exceed the rates reported for short-lasting pulses of sediment deposition in contourites by a factor of 50 and therefore appear unrealistic. Moreover, they result in entire suites of plateau structures that incidentally appear closely aligned to the pattern of atmospheric14C plateau suites rather than to any pulses of climate-controlled sediment discharge.

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Aphale, Priti Vinayak, Dhananjay Chintaman Meshram, Dnyaneshwar Maruti Mahajan, Prasad Anil Kulkarni y Shraddha Prasad Kulkarni. "Multivariate analysis of elements from the microhabitats of selected plateaus in the Western Ghats, Maharashtra, India". Journal of Threatened Taxa 11, n.º 10 (26 de agosto de 2019): 14334–48. http://dx.doi.org/10.11609/jott.4980.11.10.14334-14348.

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The Western Ghats represents a small part of the Deccan Traps continental flood basalt province that erupted about 65 million years ago. It is an area of outstanding scenic beauty and has attracted the attention of geologists, naturalists and geomorphologists for over a century. One of the unique habitats in the Western Ghats are the rocky plateaus. Previous studies have covered plant species composition, geological and geomorphological status of the rocky plateaus. An analytical study of microhabitats and associated therophytes of four rocky plateau sites was conducted. The study sites were Durgawadi Plateau, Naneghat Plateau which are basalt outcrops and Zenda plateau and Amba Plateau, which are laterite outcrops on the escarpment of the northern Western Ghats. The results revealed a correlation between basalt and lateritic rock outcrops as well as ephemeral plant elements. All four outcrops are similar in their nutrient status but the microhabitats of these plateaus are extremely different from each other.

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Oakley, J. C., P. C. Schwindt y W. E. Crill. "Dendritic Calcium Spikes in Layer 5 Pyramidal Neurons Amplify and Limit Transmission of Ligand-Gated Dendritic Current to Soma". Journal of Neurophysiology 86, n.º 1 (1 de julio de 2001): 514–27. http://dx.doi.org/10.1152/jn.2001.86.1.514.

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Long-lasting, dendritic, Ca2+-dependent action potentials (plateaus) were investigated in layer 5 pyramidal neurons from rat neocortical slices visualized by infrared-differential interference contrast microscopy to understand the role of dendritic Ca2+ spikes in the integration of synaptic input. Focal glutamate iontophoresis on visualized dendrites caused soma firing rate to increase linearly with iontophoretic current until dendritic Ca2+ responses caused a jump in firing rate. Increases in iontophoretic current caused no further increase in somatic firing rate. This limitation of firing rate resulted from the inability of increased glutamate to change evoked plateau amplitude. Similar nonlinear patterns of soma firing were evoked by focal iontophoresis on the distal apical, oblique, and basal dendrites, whereas iontophoresis on the soma and proximal apical dendrite only evoked a linear increase in firing rate as a function of iontophoretic current without plateaus. Plateau amplitude recorded in the soma decreased as the site of iontophoresis was moved farther from the soma, consistent with decremental propagation of the plateau to the soma. Currents arriving at the soma summed if plateaus were evoked on separate dendrites or if subthreshold responses were evoked from sites on the same dendrite. If plateaus were evoked at two sites on the same dendrite, only the proximal plateau was seen at the soma. Just-subthreshold depolarizations at two sites on the same dendrite could sum to evoke a plateau at the proximal site. We conclude that the plateaus prevent current from ligand-gated channels distal to the plateau-generating region from reaching the soma and directly influencing firing rate. The implications of plateau properties for synaptic integration are discussed.

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Rea, Brice R., W. Brian Whalley, Tom S. Dixon y John E. Gordon. "Plateau icefields as contributing areas to valley glaciers and the potential impact on reconstructed ELAs: a case study from the Lyngen Alps, North Norway". Annals of Glaciology 28 (1999): 97–102. http://dx.doi.org/10.3189/172756499781822020.

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AbstractPlateau icefields occur commonly in glacierized areas and not uncommonly in glaciated mountains. We report on a glacierized area of plateaux and valleys centred round the highest peak Jiehkkevárri (1833 m) in the maritime Lyngen Alps, North Norway. Some valley glaciers are fed by steep, narrow plateau glacier outlets and/or ice avalanching from the plateaux over precipitous cliffs. Plateaux must therefore be considered as “contributing areas”, if they supply ice to valley systems below. Equilibrium line altitudes (ELAs) are calculated for the valley glaciers during the Little Ice Age (LIA), accounting for both input and no input of ice from plateaux above. The results show that ELAs may be at significantly higher altitudes when plateau/x are contributing ice mass. The response of plateau glaciers to climate amelioration since the end of the LIA is somewhat different to that of valley glaciers, which appear to be retreating markedly. These findings have significant implications for the interpretation of moraine systems, glacier dynamics, the construction and reconstruction of present and former ELAs, and palaeoclimates in glacierized and glaciated mountain plateau areas.

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Ruddiman, William F. y John E. Kutzbach. "Late Cenozoic plateau uplift and climate change". Transactions of the Royal Society of Edinburgh: Earth Sciences 81, n.º 4 (1990): 301–14. http://dx.doi.org/10.1017/s0263593300020812.

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ABSTRACTSensitivity experiments with general circulation models show that uplift of plateau and mountain regions in Southern Asia and the American west during the late Cenozoic was an important factor in the evolution of Northern Hemisphere climate. The climatic trends simulated in the uplift experiments agree in direction with most trends observed in the geological record, including the tendencies toward greater regional differentiation of climate, and particularly the fragmentation into wetter and drier climatic patterns at middle latitudes. These climatic trends result from (1) increased orographic diversion of the mid-latitude westerlies, and (2) increased summer heating and winter cooling over the plateaus, which enhances seasonally reversing (monsoonal) changes in wind directions.Most previous hypotheses addressing the physical impact of orography on climate have focused on mountain ranges and have stressed relatively local responses such as upslope precipitation maxima, cooling of mountain crests due to lapse-rate effects on rising terrain, and lee-side rainshadow effects. In contrast, our results emphasise the importance of large-scale plateau orography. By redirecting the basic directions of wind flow both at surface and upper-tropospheric levels, these rising plateaux cause far-reaching climatic changes that extend across the continents as well as over the oceans.

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Bai, Yang, Jinquan Zhou y Wenjin He. "How Employee Job Burnout, Work Engagement, and Turnover Intention Relate to Career Plateau during the Epidemic". Social Sciences 12, n.º 7 (5 de julio de 2023): 394. http://dx.doi.org/10.3390/socsci12070394.

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In light of the impact of the COVID-19 epidemic on organizations and company human resource policies, multiple changes have been made to employee work behaviors. This paper developed a concept model on career plateaus, job burnout, work engagement, and turnover intention and examined it through a non-random sampling survey of 285 employees at resorts in Macao. The results revealed that career plateaus positively impact job burnout and turnover intention, and job burnout positively impacts turnover intention. The study found that career plateau negatively impacts work engagement and positively impacts turnover intention, and work engagement negatively influences turnover intention. Job burnout and work engagement partially mediate the relationship between career plateau and turnover intention. Training negatively moderates career plateau toward work engagement, and job rotation moderates career plateau toward turnover intention. Accordingly, organizations should consider the impact on employees’ careers when designing training and job rotation policies in response to the epidemic.

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Bennett, David J., Hans Hultborn, Brent Fedirchuk y Monica Gorassini. "Short-Term Plasticity in Hindlimb Motoneurons of Decerebrate Cats". Journal of Neurophysiology 80, n.º 4 (1 de octubre de 1998): 2038–45. http://dx.doi.org/10.1152/jn.1998.80.4.2038.

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Bennett, David J., Hans Hultborn, Brent Fedirchuk, and Monica Gorassini. Short-term plasticity in hindlimb motoneurons of decerebrate cats. J. Neurophysiol. 80: 2038–2045, 1998. Cat hindlimb motoneurons possess noninactivating voltage-gated inward currents that can, under appropriate conditions, regeneratively produce sustained increments in depolarization and firing of the cell (i.e., plateau potentials). Recent studies in turtle dorsal horn neurons and motoneurons indicate that facilitation of plateaus occurs with repeated plateau activation (decreased threshold and increased duration; this phenomenon is referred to as warm-up). The purpose of the present study was to study warm-up in cat motoneurons. Initially, cells were studied by injecting a slow triangular current ramp intracellularly to determine the threshold for activation of the plateau. In cells where the sodium spikes were blocked with intracellular QX314, plateau activation was readily seen as a sudden jump in membrane potential, which was not directly reversed as the current was decreased (cf. hysteresis). With normal spiking, the plateau activation (the noninactivating inward current) was reflected by a steep and sustained jump in firing rate, which was not directly reversed as the current was decreased (hysteresis). Repetitive plateau activation significantly lowered the plateau activation threshold in 83% of cells (by on average 5 mV and 11 Hz with and without QX314, respectively). This interaction between successive plateaus (warm-up) occurred when tested with 3- to 6-s intervals; no interaction occurred at times >20 s. Plateaus initiated by synaptic activation from muscle stretch were also facilitated by repetition. Repeated slow muscle stretches that produced small phasic responses when a cell was hyperpolarized with intracellular current bias produced a larger and more prolonged responses (plateau) when the bias was removed, and the amplitude and duration of this response grew with repetition. The effects of warm-up seen with intracellular recordings during muscle stretch could also be recorded extracellularly with gross electromyographic (EMG) recordings. That is, the same repetitive stretch as above produced a progressively larger and more prolonged EMG response. Warm-up may be a functionally important form of short-term plasticity in motoneurons that secures efficient motor output once a threshold level is reached for a significant period. Finally, the finding that warm-up can be readily observed with gross EMG recordings will be useful in future studies of plateaus in awake animals and humans.

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Johannessen, Peter N. "Sedimentology and sequence stratigraphy of paralic and shallow marine Upper Jurassic sandstones in the northern Danish Central Graben". Geological Survey of Denmark and Greenland (GEUS) Bulletin 1 (28 de octubre de 2003): 367–402. http://dx.doi.org/10.34194/geusb.v1.4678.

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Paralic and shallow marine sandstones were deposited in the Danish Central Graben during Late Jurassic rifting when half-grabens were developed and the overall eustatic sea level rose. During the Kimmeridgian, an extensive plateau area consisting of the Heno Plateau and the Gertrud Plateau was situated between two highs, the Mandal High to the north, and the combined Inge and Mads Highs to the west. These highs were land areas situated on either side of the plateaus and supplied sand to the Gertrud and Heno Plateaus. Two graben areas, the Feda and Tail End Grabens, flanked the plateau area to the west and east, respectively. The regressive–transgressive succession consists of intensely bioturbated shoreface sandstones, 25–75 m thick. Two widespread unconformities (SB1, SB2) are recognised on the plateaus, forming the base of sequence 1 and sequence 2, respectively. These unconformities were created by a fall in relative sea level during which rivers may have eroded older shoreface sands and transported sediment across the Heno and Gertrud Plateaus, resulting in the accumulation of shoreface sandstones farther out in the Feda and Tail End Grabens, on the south-east Heno Plateau and in the Salt Dome Province. During subsequent transgression, fluvial sediments were reworked by high-energy shoreface processes on the Heno and Gertrud Plateaus, leaving only a lag of granules and pebbles on the marine transgressive surfaces of erosion (MTSE1, MTSE2). The sequence boundary SB1 can be traced to the south-east Heno Plateau and the Salt Dome Province, where it is marked by sharp-based shoreface sandstones. During low sea level, erosion occurred in the southern part of the Feda Graben, which formed part of the Gertrud and Heno Plateaus, and sedimentation occurred in the Norwegian part of the Feda Graben farther to the north. During subsequent transgression, the southern part of the Feda Graben began to subside, and a succession of backstepping back-barrier and shoreface sediments, 90 m thick, was deposited. In the deep Tail End and Feda Grabens and the Salt Dome Province, sequence boundary SB2 is developed as a conformity, indicating that there was not a significant fall in relative sea level in these grabens, probably as a result of high subsidence rates. Backstepping lower shoreface sandstones overlie SB2 and show a gradual fining-upwards to offshore claystones that are referred to the Farsund Formation. On the plateaus, backstepping shoreface sandstones of sequence 2 are abruptly overlain by offshore claystones, indicating a sudden deepening and associated cessation of sand supply, probably caused by drowning of the sediment source areas on the Mandal, Inge and Mads Highs. During the Volgian, the Gertrud Plateau began to subside and became a graben. During the Late Kimmeridgian – Ryazanian, a long-term relative sea-level rise resulted in deposition of a thick succession of offshore claystones forming highstand and transgressive systems tracts on the Heno Plateau, and in the Gertrud, Feda and Tail End Grabens.

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Chen, Jile, Peimin Zhu, Yuefeng Yuan y Guifan Chen. "Formation of the Tibetan Plateau during the India-Eurasia Convergence: Insight from 3-D Multi-Terrane Thermomechanical Modeling". Journal of Earth Science 35, n.º 1 (febrero de 2024): 112–30. http://dx.doi.org/10.1007/s12583-023-1931-0.

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AbstractVarious models exist to explain the formation of the Tibetan Plateau, including “tectonic escape”, “pure shear thickening”, “convective removal of the lithospheric mantle”, and “lower crustal flow” model. The first two models are primarily constructed on pure mechanical models but are unable to reasonably explain the tension and shear phenomena inside the plateau. The latter two are rheological dynamic models based on deep geophysical observations. However, the spatial range of the lower crustal flow and its role in the plateau formation/uplift remain controversial. Five multi-terrane viscoplastic thermomechanical models were constructed to simulate the uplift and lithospheric structure change of the Tibetan Plateau during the post-collision stage (since 35 Ma) under the convergence of the Indian Plate. Results show that the plateau’s formation begins with crustal thickening, blocked by strong terranes at the northern plateau, and expanded laterally to the east. The lithosphere thickens gradually and experiences delamination at its base, elevating temperature within the crust and forming partial melting layers in the central plateau. As convergence persists on the southern side, the northern plateau’s lithosphere bends downward and undergoes delamination, further heating the crust and promoting the northward and eastward flow of partial melting layers, leading to secondary uplift around the plateau.

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Signorile, Joseph F., Michelle P. Carmel, Shenghan Lai y Bernard A. Roos. "Early plateaus of power and torque gains during high- and low-speed resistance training of older women". Journal of Applied Physiology 98, n.º 4 (abril de 2005): 1213–20. http://dx.doi.org/10.1152/japplphysiol.00742.2004.

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Periodization is the most effective approach to resistance training; however, optimal cycle lengths for older persons are not known. This study examined the durations of performance increments, plateaus, and decrements in women, ages 61–75 yr, over 9 wk of isokinetic training. After a 2-wk adaptation cycle, older women trained for either power (PWR; 4.73 rad/s; n = 9) or strength (STR; 1.05 rad/s; n = 8), 3 days/wk with a 1-day recovery between sessions. Repetitions were initially selected to equilibrate work volume between groups. Average power (AP), peak torque (PT), and total work (TW) curves were analyzed using forward and backward stepwise regression to ascertain inflections and plateaus. PWR training produced the highest AP, whereas STR produced the highest PT. TW was similar between groups. The AP curves of the PWR group initially showed a steep positive slope and then plateaued during week 3. The right leg plateau lasted throughout training, whereas the left leg showed another positive inflection during weeks 7 and 8. PWR group TW curves showed positive slopes throughout training. STR group PT curves for both legs showed initial positive slopes peaking between weeks 3 and 4 and declining thereafter. The TW curves for both legs showed slight negative slopes across the first 2 wk, steep positive slopes during weeks 3–6, and a final plateau. Because improvements plateau early during PWR and STR training, isokinetic training prescriptions for optimizing strength and power improvements in older persons should use cycles of 3–4 wk to maximize gains.

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Yi, Shuang-Xi, Mei Du y Tong Liu. "Statistical Analyses of the Energies of X-Ray Plateaus and Flares in Gamma-Ray Bursts". Astrophysical Journal 924, n.º 2 (1 de enero de 2022): 69. http://dx.doi.org/10.3847/1538-4357/ac35e7.

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Abstract Distinct X-ray plateau and flare phases have been observed in the afterglows of gamma-ray bursts (GRBs), and most of them should be related to central engine activities. In this paper, we collect 174 GRBs with X-ray plateau phases and 106 GRBs with X-ray flares. There are 51 GRBs that overlap in the two selected samples. We analyze the distributions of the proportions of the plateau energy E plateau and the flare energy E flare relative to the isotropic prompt emission energy E γ,iso. The results indicate that they well meet the Gaussian distributions and the medians of the logarithmic ratios are ∼−0.96 and −1.39 in the two cases. Moreover, strong positive correlations between E plateau (or E flare ) and E γ,iso with slopes of ∼0.95 (or ∼0.80) are presented. For the overlapping sample, the slope is ∼0.80. We argue that most of X-ray plateaus and flares might have the same physical origin but appear with different features because of the different circumstances and radiation mechanisms. We also test the applicabilities of two models, i.e., black holes surrounded by fractured hyperaccretion disks and millisecond magnetars, on the origins of X-ray plateaus and flares.

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Shapiro, Nicholas P. y Robert H. Lee. "Synaptic Amplification Versus Bistability in Motoneuron Dendritic Processing: A Top-Down Modeling Approach". Journal of Neurophysiology 97, n.º 6 (junio de 2007): 3948–60. http://dx.doi.org/10.1152/jn.00084.2007.

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Motoneurons have been shown to exhibit both bistable firing and synaptic amplification. Both of these behaviors have generally been attributed to a single mechanism—dendritic plateau potentials based on L-type Ca2+ conductances. However, our recent discovery of a fast-amplification mode calls this into question. Here we examine the possibility that two mechanisms underlie these behaviors, one being a slow-mode bistability mechanism (i.e., the L-type Ca2+-conductance–based dendritic plateaus) and the other being a theoretical fast-mode amplification mechanism. A “top-down” motoneuron model that encapsulated these and other hypotheses was developed in which these mechanisms could be explored. The resulting final model simultaneously exhibits synaptic amplification, plateau potential formation, bistable firing patterns, and current–voltage ( I– V) and frequency–current ( F– I) hystereses. This model suggests that amplification and plateaus are mutually exclusive in the same dendrite/dendritic branch. Thus we predict that plateau generation does not occur in all dendritic branches. This could be readily accomplished by a large degree of variation in the density of L-type Ca2+ channels believed to underlie plateau formation in these cells with the added benefit of spreading plateau onset over a wider voltage range, as is observed experimentally.

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Wheatley, David, Winston Seiler y Marjorie Chan. "The Wind-Swept Nautilus, Enigmatic Clastic Pipes, and Toadstool Landforms: Geologic Features of the Paria Plateau". Geosites 1 (31 de diciembre de 2019): 1–11. http://dx.doi.org/10.31711/geosites.v1i1.67.

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The Colorado Plateau occupies much of the southwestern United States including portions of Arizona, Colorado, Utah, and New Mexico. This region presents unobstructed views from mesa tops, beautifully colored soils, lone standing buttes, and canyons cut thousands of feet deep. The Colorado Plateau represents a well-preserved window into the Earth’s history. Today, the rocks of the Colorado Plateau lie roughly horizontally, as they were deposited hundreds of millions of years ago. The Plateau’s rise has motivated rivers, in their downhill progress, to carve innumerable canyons. These river canyons allow any nature-lover the opportunity to gaze at 100s of millions of years of geologic history. Within the larger Colorado Plateau, the Paria Plateau straddles the Utah and Arizona borders, and includes the Vermilion Cliff s National Monument, the Paria Canyon-Vermilion Cliffs Wilderness Area, and the southern extent of the Grand Staircase Escalante National Monument (GSENM; pre-2018 boundaries). The Paria Plateau is best known for spectacularly colored, wind-sculpted features such as Coyote Buttes and “The Wave,” where vivid colors accent cross-strata resembling a cresting ocean wave. The Plateau is also recognized for the geologically notable Vermilion Cliff s, Buckskin Gulch slot canyon, White Pocket area, and the Paria River Canyon. Although only two, dual-lane highways circumvent the plateau, several wash-boarded gravel and deeply mud-rutted roads allow access to its interior. From these dirt roads, a few sandy, four-wheel drive paths diminish as they extend and branch into the plateau’s interior. Overall, the Paria Plateau is a relatively quiet and little-visited wilderness.

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20

Ocal, M. K. y S. S. Sabanci. "Lateral and medial tibial plateau angles in normal dogs". Veterinary and Comparative Orthopaedics and Traumatology 27, n.º 02 (2014): 135–40. http://dx.doi.org/10.3415/vcot-13-04-0043.

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SummaryTo measure lateral and medial tibial plateau angle values in isolated canine tibiae and to compare lateral and medial tibial plateau angle values between dogs based on sex and breed.Tibiae of 90 dogs from 24 different breeds were used. Photographs were taken of the medial and lateral aspects of the tibiae for measurement of the medial and lateral tibial plateau angles. Additionally, the medial tibial plateau angle was measured from radiographs of the tibiae. Two-way analysis of variance was used to test the effects of side, sex and breed on the medial and lateral tibial plateau angles as measured from photographs as well as the medial tibial plateal angles as measured from radiographs. The photographic and radiographic medial tibial plateau angles were compared by paired t-test, whereas the medial and lateral photographic tibial plateau angles were compared by t-test.When all dogs were included in the analysis, the difference between the mean medial tibial plateau angle (24.0 ± 3.19°) and the mean lateral tibial plateau angle (25.5 ± 3.84°) as measured from photographs was significant (p <0.05). The difference in the photographic medial tibial plateau angle between male and female dogs was significant (p <0.05), whereas the difference in the photographic lateral tibial plateau angle between sexes was not significant. There was a significant difference between the medial and lateral tibial plateau angles as measured from photographs in male dogs (p <0.05) but not in female dogs. Breed comparisons also showed significant differences for the photographic lateral tibial plateau angle (p <0.05).The axial rotation of the femoral condyles on the tibial plateau is probably affected by the discrepancy between the medial and lateral tibial plateau angles, and this difference in certain breeds might influence the prevalence of cranial cruciate ligament disease.

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21

Pramod, C. y A. K. Pradeep. "Observations on the flowering plant diversity of Madayippara, a southern Indian lateritic plateau from Kerala, India". Journal of Threatened Taxa 13, n.º 2 (27 de febrero de 2021): 17780–806. http://dx.doi.org/10.11609/jott.3883.13.2.17780-17806.

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Northern Kerala of southern India is characterized by widely spread lateritic plateaus which provide an extremely harsh physical environment for life leading to the development of specialized plant communities with a large number of endemic and habitat specific species. Madayippara, a midland lateritic plateau located in the Kannur District of northern Kerala is an icon of rich floristic diversity and endemism. The plateau forms a number of microhabitats due to the difference in geographic terrain and soil cover, thus forming a complex of habitats with diverse forms of plants, mainly ephemeral herbs. Out of the 636 flowering plant taxa recorded from the microhabitats of the plateau, within a limited area of 3.65km2, 160 (c. 25%) are endemics. Most of the endemic species occur in specialized microhabitats. The plateau is the type locality of 11 taxa. Lateritic plateaus of southern India, which are associated with characteristic and rich biodiversity, are now under varied types of anthropogenic threats such as large scale mining for bricks and clay, and they need urgent attention for conservation of the biodiversity.

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22

Arrasmith, Andrew, M. Cerezo, Piotr Czarnik, Lukasz Cincio y Patrick J. Coles. "Effect of barren plateaus on gradient-free optimization". Quantum 5 (5 de octubre de 2021): 558. http://dx.doi.org/10.22331/q-2021-10-05-558.

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Barren plateau landscapes correspond to gradients that vanish exponentially in the number of qubits. Such landscapes have been demonstrated for variational quantum algorithms and quantum neural networks with either deep circuits or global cost functions. For obvious reasons, it is expected that gradient-based optimizers will be significantly affected by barren plateaus. However, whether or not gradient-free optimizers are impacted is a topic of debate, with some arguing that gradient-free approaches are unaffected by barren plateaus. Here we show that, indeed, gradient-free optimizers do not solve the barren plateau problem. Our main result proves that cost function differences, which are the basis for making decisions in a gradient-free optimization, are exponentially suppressed in a barren plateau. Hence, without exponential precision, gradient-free optimizers will not make progress in the optimization. We numerically confirm this by training in a barren plateau with several gradient-free optimizers (Nelder-Mead, Powell, and COBYLA algorithms), and show that the numbers of shots required in the optimization grows exponentially with the number of qubits.

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23

Arrasmith, Andrew, M. Cerezo, Piotr Czarnik, Lukasz Cincio y Patrick J. Coles. "Effect of barren plateaus on gradient-free optimization". Quantum 5 (5 de octubre de 2021): 558. http://dx.doi.org/10.22331/q-2021-10-05-558.

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Barren plateau landscapes correspond to gradients that vanish exponentially in the number of qubits. Such landscapes have been demonstrated for variational quantum algorithms and quantum neural networks with either deep circuits or global cost functions. For obvious reasons, it is expected that gradient-based optimizers will be significantly affected by barren plateaus. However, whether or not gradient-free optimizers are impacted is a topic of debate, with some arguing that gradient-free approaches are unaffected by barren plateaus. Here we show that, indeed, gradient-free optimizers do not solve the barren plateau problem. Our main result proves that cost function differences, which are the basis for making decisions in a gradient-free optimization, are exponentially suppressed in a barren plateau. Hence, without exponential precision, gradient-free optimizers will not make progress in the optimization. We numerically confirm this by training in a barren plateau with several gradient-free optimizers (Nelder-Mead, Powell, and COBYLA algorithms), and show that the numbers of shots required in the optimization grows exponentially with the number of qubits.

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24

Mouritsen, Kim N., Lone T. Mouritsen y K. Thomas Jensen. "Change of Topography and Sediment Characteristics on an Intertidal Mud-Flat Following Mass-Mortality of the Amphipod Corophium Volutator". Journal of the Marine Biological Association of the United Kingdom 78, n.º 4 (noviembre de 1998): 1167–80. http://dx.doi.org/10.1017/s0025315400044404.

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A Corophium-bed characterized by a mosaic of emerged areas and tidal pools during low water was established on an intertidal flat in the southern part of the Danish Wadden Sea. In spring 1990, the plateaux harboured relatively high densities of the amphipod Corophium volutator, whereas the amphipods were almost absent in the pools. Following a parasite-induced mass-mortality in the population of Corophium, summer 1990, the plateaux of the bed were subjected to sediment erosion. The heterogeneous plateau-pool structure disappeared, accompanied by increased median particle diameter and decreased silt content in the former plateau sediment. These events were accompanied by increased chlorophyll-a concentrations in the sediment of both plateau and pool areas.The results suggest Corophium volutator to be the single most important organism stabilizing the plateau sediment, and hence, the heterogeneous topographic structure of the Corophium-bed. It is proposed that the stabilizing effect of Corophium burrows also in deeper sediment strata may outweigh the surface stabilizing influence of epipelic diatoms, as well as the negative effect of amphipods eating the diatoms, in non-cohesive coarser sediments.

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25

Zängl, Günther y Joseph Egger. "Diurnal Circulation of the Bolivian Altiplano. Part II: Theoretical and Model Investigations". Monthly Weather Review 133, n.º 12 (1 de diciembre de 2005): 3624–43. http://dx.doi.org/10.1175/mwr3033.1.

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Abstract The first step in the evolution of the diurnal circulation of grand plateaus is the matutinal buildup of inflow through mountain passes connecting the lowlands with the plateau proper. Maximum inward transport is attained in the afternoon. Corresponding observations at the Bolivian Altiplano are described in the first part of this paper. Here, both a linear model and the fifth-generation Pennsylvania State University–NCAR Mesoscale Model (MM5) are used to better understand the dynamics of this process. First discussed is the solution to the linear sea-breeze problem where a heated fluid layer is restricted to the half plane x ≤ 0. Rapidly moving barotropic modes lead to surface pressure fall in the heated half plane and to pressure rise for x ≥ 0. Slow baroclinic modes describe the horizontally expanding inflow toward the heated layer near the ground with return flow aloft. This basic structure of the response carries over to more complicated topographies where a heated plateau with vertical sidewalls is separated from the lowlands by a barrier and a pass. The baroclinic modes are fanning out from the pass into the plateau’s interior in linear numerical calculations. These flow patterns hardly change when additional slopes connect the plains and the plateau. The restrictions imposed by the linear approach are removed step by step in simulations with MM5 in which an idealized plateau with an optional pass is prescribed. There is good agreement with respect to the basic flow pattern, but the linear theory is found to overestimate inflow velocities because of its neglect of momentum and perturbation temperature advection. Moreover, a front moves from the pass into the plateau’s interior where the stratification is neutral or even unstable, a situation that is beyond the scope of the linear theory. The upslope winds evolving at the slope connecting the plateau with the lowlands are unimportant for the thermal circulation of the plateau, a result also suggested by the linear theory. Finally, simulations of the diurnal cycle are performed for the real topography of the Altiplano. The presentation of results concentrates on the observation sites. It is demonstrated that the idealized calculations help to better understand the resulting flows as well as the observations reported in Part I. The total inflow to the Altiplano is discussed as well.

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26

Tian, Xiao, Jia-Lun Li, Shuang-Xi Yi, Yu-Peng Yang, Jian-Ping Hu, Yan-Kun Qu y Fa-Yin Wang. "Radio Plateaus in Gamma-Ray Burst Afterglows and Their Application in Cosmology". Astrophysical Journal 958, n.º 1 (1 de noviembre de 2023): 74. http://dx.doi.org/10.3847/1538-4357/acfed8.

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Abstract The plateau phase in radio afterglows has been observed in very few gamma-ray bursts (GRBs), and in this paper, 27 radio light curves with plateau phases were acquired from the published literature. We obtain the related parameters of the radio plateau, such as temporal indexes during the plateau phase (α 1 and α 2), break time (T b,z), and the corresponding radio flux (F b). The two-parameter Dainotti relation between the break time of the plateau and the corresponding break luminosity (L b,z) in the radio band is L b , z ∝ T b , z − 1.20 ± 0.24 . Including the isotropic energy E γ,iso and peak energy E p,i, the three-parameter correlations for the radio plateaus are written as L b , z ∝ T b , z − 1.01 ± 0.24 E γ , iso 0.18 ± 0.09 and L b , z ∝ T b , z − 1.18 ± 0.27 E p , i 0.05 ± 0.28 , respectively. The correlations are less consistent with those of the X-ray and optical plateaus, implying that radio plateaus may have a different physical mechanism. The typical frequencies crossing the observational band may be a reasonable hypothesis that causes the breaks of the radio afterglows. We calibrate the GRB empirical luminosity correlations as a standard candle for constraining cosmological parameters and find that our samples can constrain the flat ΛCDM model well but are not sensitive to the nonflat ΛCDM model. By combining GRBs with other probes, such as supernovae and the CMB, the constraints on the cosmological parameters are Ωm = 0.297 ± 0.006 for the flat ΛCDM model and Ωm = 0.283 ± 0.008, ΩΛ = 0.711 ± 0.006 for the nonflat ΛCDM model.

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27

Lee, Patrick C. B. "Career plateau and professional plateau". ACM SIGCPR Computer Personnel 20, n.º 4 (diciembre de 1999): 25–38. http://dx.doi.org/10.1145/571475.571478.

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28

Wallach, J. L. y M. Rheault. "Uplift of the Tug Hill Plateau in northern New York State". Canadian Journal of Earth Sciences 47, n.º 8 (agosto de 2010): 1055–77. http://dx.doi.org/10.1139/e10-031.

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The Tug Hill Plateau is a roughly elliptical-shaped area located in northern New York State that rises above the adjacent landscape and is underlain predominantly by Middle to Upper Ordovician strata. Its elevated character is interpreted as a passive response to the tectonic uplift of the adjacent Precambrian basement located to the east and northeast of the plateau. Uplift of the basement is also inferred to have resulted in the strata on the plateau and in the topographically lower terrain to the north dipping gently towards the southwest. Tilting of the plateau was probably facilitated by rotation along the newly recognized regionally extensive Black River fault, which separates the plateau from the uplifted basement and marks the plateau’s east-northeastern limit. The northern limit of the plateau, accentuated by a pronounced escarpment, is aligned with the northeast-trending Carthage–Colton shear zone, a major Precambrian tectonic boundary. Uplift of the Adirondack Highlands and Tug Hill Plateau, relative to their counterparts northwest of the shear zone, is believed to have been enabled by reactivation of the Carthage–Colton shear zone.

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29

Michman, Elisheva, Meirav Oded y Roy Shenhar. "Dual Block Copolymer Morphologies in Ultrathin Films on Topographic Substrates: The Effect of Film Curvature". Polymers 14, n.º 12 (12 de junio de 2022): 2377. http://dx.doi.org/10.3390/polym14122377.

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The ability to create mixed morphologies using easily controlled parameters is crucial for the integration of block copolymers in advanced technologies. We have previously shown that casting an ultrathin block copolymer film on a topographically patterned substrate results in different deposited thicknesses on the plateaus and in the trenches, which leads to the co-existence of two patterns. In this work, we highlight the dependence of the dual patterns on the film profile. We suggest that the steepness of the film profile formed across the plateau edge affects the nucleation of microphase-separated domains near the plateau edges, which influences the morphology that develops on the plateau regions. An analysis of the local film thicknesses in multiple samples exhibiting various combinations of plateau and trench widths for different trench depths enabled the construction of phase diagrams, which unraveled the intricate dependence of the formed patterns not only on the curvature of the film profile but also on the fraction of the film that resides in the trenches. Our analysis facilitates the prediction of the patterns that would develop in the trenches and on the plateaus for a given block copolymer film of known thickness from the dimensions of the topographic features.

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30

Marchetti, David W., M. Scott Harris, Christopher M. Bailey, Thure E. Cerling y Sarah Bergman. "Timing of glaciation and last glacial maximum paleoclimate estimates from the Fish Lake Plateau, Utah". Quaternary Research 75, n.º 1 (enero de 2011): 183–95. http://dx.doi.org/10.1016/j.yqres.2010.09.009.

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AbstractThe High Plateaus of Utah include seven separate mountain ranges that supported glaciers during the Pleistocene. The Fish Lake Plateau, located on the eastern edge of the High Plateaus, preserves evidence of at least two glacial advances. Four cosmogenic 3He exposure ages of boulders in an older moraine range from 79 to 159 ka with a mean age of 129 ± 39 ka and oldest ages of 152 ± 3 and 159 ± 5 ka. These ages suggest deposition during the type Bull Lake glaciation and Marine Oxygen Isotope Stage (MIS) 6. Twenty boulder exposure ages from four different younger moraines indicate a local last glacial maximum (LGM) of ~ 21.1 ka, coincident with the type Pinedale glaciation and MIS 2. Reconstructed Pinedale-age glaciers from the Fish Lake Plateau have equilibrium-line altitudes ranging from 2950 to 3190 m. LGM summer temperature depressions for the Fish Lake Plateau range from −10.7 to −8.2°C, assuming no change in precipitation. Comparison of the Fish Lake summer temperature depressions to a regional dataset suggests that the Fish Lake Plateau may have had a slight increase (~ 1.5× modern) in precipitation during the LGM. A series of submerged ridges in Fish Lake were identified during a bathymetric survey and are likely Bull Lake age moraines.

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31

Furuchi, Rito, Hiroki Nakano, Norikazu Todoroki y Toru Sakai. "Magnetization process of the S = 1/2 Heisenberg antiferromagnet on the floret pentagonal lattice". Journal of Physics Communications 5, n.º 12 (1 de diciembre de 2021): 125008. http://dx.doi.org/10.1088/2399-6528/ac3f7a.

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Abstract We study the S = 1/2 Heisenberg antiferromagnet on the floret pentagonal lattice by numerical diagonalization method. This system shows various behaviours that are different from that of the Cairo-pentagonal-lattice antiferromagnet. The ground-state energy without magnetic field and the magnetization process of this system are reported. Magnetization plateaux appear at one-ninth height of the saturation magnetization, at one-third height, and at seven-ninth height. The magnetization plateaux at one-third and seven-ninth heights come from interactions linking the sixfold-coordinated spin sites. A magnetization jump appears from the plateau at one-ninth height to the plateau at one-third height. Another magnetization jump is observed between the heights corresponding to the one-third and seven-ninth plateaux; however the jump is away from the two plateaux, namely, the jump is not accompanied with any magnetization plateaux. The jump is a peculiar phenomenon that has not been reported.

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32

Aerts, JG, JM Bogaard, SE Overbeek, AF Verbraak y P. Thio. "Extrapolation of methacholine log-dose response curves with a Cumulative Gaussian Distribution function". European Respiratory Journal 7, n.º 5 (1 de mayo de 1994): 895–900. http://dx.doi.org/10.1183/09031936.94.07050895.

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Methacholine provocation tests are aimed at determining bronchial responsiveness. Recent investigations stress the importance of considering the entire log-dose response curve, yielding not only the provocative dose producing a 20% change in forced expiratory volume in one second (FEV1) (PC20), but also the plateau value and the steepest slope of the curve (reactivity). In three control subjects and seven patients with mild to moderate asthma, we have obtained methacholine log-dose response curves in which a plateau was reached. A new model, the Cumulative Gaussian Distribution (CGD) function was fitted to the whole curve. The upper part of the curve was also analysed with the Hofstee equation, which has been used in a number of other investigations and aimed at plateau estimation. The plateau values obtained by the fits were compared with the values actually measured (average response of last 3 points with a variation coefficient < 5% of the mean value) by using the coefficient of determination (R2) (Applied Statistics. Sachs). If all data points were considered, both fits yielded a plateau which slightly overestimated the measured plateau values. R2 for the CGD fit ranged from 0.93-0.99, indicating a highly significant correlation between actual and fitted data points. If the curves were truncated, such that the last four provocative doses were omitted from the analysis, the CGD fit still yielded plateau values; the mean difference from the measured plateaux, in % of the measured plateau values, was -2.6% (SD 18.2). In only three out of the 10 cases did the Hofstee equation yield plateau values with a deviation from 'measured' < 47% of the measured value.(ABSTRACT TRUNCATED AT 250 WORDS)

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33

Melo, Felipe F., Valeria C. F. Barbosa, Leonardo Uieda, Vanderlei C. Oliveira Jr. y João B. C. Silva. "Estimating the nature and the horizontal and vertical positions of 3D magnetic sources using Euler deconvolution". GEOPHYSICS 78, n.º 6 (1 de noviembre de 2013): J87—J98. http://dx.doi.org/10.1190/geo2012-0515.1.

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We have developed a new method that drastically reduces the number of the source location estimates in Euler deconvolution to only one per anomaly. Our method employs the analytical estimators of the base level and of the horizontal and vertical source positions in Euler deconvolution as a function of the [Formula: see text]- and [Formula: see text]-coordinates of the observations. By assuming any tentative structural index (defining the geometry of the sources), our method automatically locates plateaus, on the maps of the horizontal coordinate estimates, indicating consistent estimates that are very close to the true corresponding coordinates. These plateaus are located in the neighborhood of the highest values of the anomaly and show a contrasting behavior with those estimates that form inclined planes at the anomaly borders. The plateaus are automatically located on the maps of the horizontal coordinate estimates by fitting a first-degree polynomial to these estimates in a moving-window scheme spanning all estimates. The positions where the angular coefficient estimates are closest to zero identify the plateaus of the horizontal coordinate estimates. The sample means of these horizontal coordinate estimates are the best horizontal location estimates. After mapping each plateau, our method takes as the best structural index the one that yields the minimum correlation between the total-field anomaly and the estimated base level over each plateau. By using the estimated structural index for each plateau, our approach extracts the vertical coordinate estimates over the corresponding plateau. The sample means of these estimates are the best depth location estimates in our method. When applied to synthetic data, our method yielded good results if the bodies produce weak- and mid-interfering anomalies. A test on real data over intrusions in the Goiás Alkaline Province, Brazil, retrieved sphere-like sources suggesting 3D bodies.

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34

Babkin, E. M., E. A. Babkina, M. O. Leibman, R. R. Khayrullin y A. V. Khomutov. "Monitoring of the relief changes in polygonal peat plateaus adjacent to the highway Zapolyarnoe — Tazovsky". Arctic and Antarctic Research 68, n.º 4 (12 de diciembre de 2022): 384–405. http://dx.doi.org/10.30758/0555-2648-2022-68-4-384-405.

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The thawing of polygonal ice wedges determines the dynamics of polygonal peatland relief. The polygonal peat plateaus in the Pur-Taz interfluve account for an average of 6,5 % of the total area. The purpose of the proposed study is to establish the short-term rates and direction of change in the plateaus’ relief under the combined action of technogenic and natural factors, using monitoring data for the period 2005–2022. Based on satellite images and orthophotoplans, elements of the peat plateaus have been outlined and their areas have been determined for different time slices. The studies were carried out on a peat plateau immediately adjacent to the highway (T1) and on a background peat plateau at a distance of about 1.5 km from the highway (T2). To identify the natural causes of changes in the relief of the peat plateaus, the influence of climatic parameters is considered. The rates of relief change in natural conditions and under the impact of the highway are also compared. It has been established that in the area to the north-west of the highway the relief of the T1 polygonal peat plateau has stabilized. In the south-east section of T1, degradation has sharply increased after the construction of the highway. Due to the degradation of the polygons, the polygonal troughs expanded. In the background peat plateau T2, the rate of relief degradation is somewhat higher than in the northwestern portion of T1. Comparison of the main climatic parameters and degradation rates of the polygonal relief did not show any clear correlations. Probably, of greater importance are the regime of atmospheric precipitation, the redistribution of surface runoff and recurrence of flooding and drainage of the polygonal troughs, determined by the rhythmic course of the relief degradation.

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35

Bachvarova, Darina, Aleksandar Doichinov y Rasim Halilov. "Comparative analysis of the myriapod fauna (Diplopoda, Chilopoda) of the Shumen Plateau and the Madara Plateau (Northeastern Bulgaria)". Acta Scientifica Naturalis 9, n.º 3 (1 de noviembre de 2022): 36–50. http://dx.doi.org/10.2478/asn-2022-0020.

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Abstract At present, the inventory lists of the Myriapoda of many geographical areas in Bulgaria and the comparative analyzes of the similarity between such local faunas are scarce or completely missing. The present paper presents the results of the comparative analysis of α- and β-diversity of the myriapoda communities in natural habitats in two regions in Northeastern Bulgaria – the Shumen Plateau and the Madara Plateau. The compared habitats in these plateaus have similar geographical, soil and climatic conditions, and similar species composition of plant formations. The analysis of the structure of the myriapoda communities included estimation of species diversity by determining the Shannon-Wiever index (H’) and the Berger-Parker index (d). The degree of similarity between the species composition of the communities was analyzed by the Czekanowski-Dice-Sörensen, Jaccard, Bray-Curtis, Horn, Morisita-Horn indices and the corrected Chao-Sörensen and Chao-Jaccard indices. The species diversity of the millipede community in the Shumen Plateau is much greater than that of the Madara Plateau, while the diversity of the centipede communities in the two plateaus does not differ significantly. In both classes the greatest species diversity is registered in deciduous and mixed deciduous-coniferous forests. Chao-Sörensen and Chao-Jaccard indices of similarity for the myriapod communities in these habitats are the highest, approaching 1, in contrast to the other sites where the registered species composition of the centipedes is smaller and the degree of similarity is about 0.6.

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36

Arvanitakis, Alexandra V., Kerry C. Mian, Raymond Kreienkamp y Charles E. Rhoades. "Tibial Plateau Fracture Following Low Energy Fall in the Rocky Mountains". Kansas Journal of Medicine 12, n.º 3 (21 de agosto de 2019): 91–93. http://dx.doi.org/10.17161/kjm.v12i3.11800.

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Tibial plateau fractures are debilitating injuries. They can occurin younger individuals who sustain a high energy trauma or, withincreasing age, lesser degrees of trauma and underlying bone pathology such as osteoporosis, metabolic bone disease, and malignancy.1Outside these cases, tibial plateau fractures are relatively uncommon.However, these fractures can occur in healthy patients who have sustained direct trauma to the knee.Fractures of the tibial plateau often are classified according to theSchatzker or AO classification systems.2,3 These systems evaluate theinvolvement of both the medial and lateral plateaus, degree of comminution, extension into the joint, and displacement (both articularsurfaces and the relationship of the diaphysis to the metaphysis).Most tibial plateau fractures occur in the lateral aspect of the tibialplateau.1 The increased frequency of lateral fractures is due to themedial tibial plateau being able to resist higher weight-bearing loaddue to the presence of more cancellous bone. More importantly, thelateral plateau has more articular surface exposed during extensioncompared to the medial plateau, which increases likelihood of injury.4The standard of care for most displaced tibial plateau fracturesis surgical management with open reduction and internal fixation(ORIF).5 Conservative management, such as leg bracing, is an optionfor fractures that are nondisplaced or in patients too fragile for surgical intervention. In the senior population, a total knee arthroplasty(TKA) is a less common option. Tibial plateau fractures, particularlymedial tibial plateau fractures, caused by direct trauma in the elderly,non-osteoporotic population are uncommon.We present the case of an active male without overt risk for severefracture (10-year fracture risk of 10% via FRAX score) who wasworking to repair a trail in the Rocky Mountains. While other injurieswere more likely given the mechanism of injury and patient risk, thiscase highlighted the importance of considering tibial plateau fracture,even in atypical settings without significant risk. Improved awarenessof this mechanism of injury will lead to more accurate diagnosis andgreater post-injury management.

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37

Deng, Min, Yong-Jian Wang, Yu Gang y Jian-Fei Chen. "Effect of uniaxial strain on the electronic transport through disordered graphene p–n junctions". Modern Physics Letters B 30, n.º 26 (30 de septiembre de 2016): 1650337. http://dx.doi.org/10.1142/s0217984916503371.

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Using the non-equilibrium Green’s function method, we investigated theoretically the electron transport through a disordered graphene p–n junction under a perpendicular magnetic field. A uniaxial strain is applied to the graphene sheet. It is found that the conductance versus the on-site energy of the right electrode exhibits the successive step-like structure in the n–n region, however, a zero value plateau followed by the successive oscillation peaks in the p–n region. When the longitudinal or transverse strain is applied, the zero value plateau almost remains intact, while the oscillation peaks are greatly enhanced with increasing the strain strength, and depending on the orientation of the applied strain, the oscillation peaks shift towards the positive or negative energy upon increasing the strain. In the presence of the disorder, the characteristic conductance plateaus emerge at [Formula: see text], [Formula: see text], etc. for the appropriate disorder strength. With the rise of the strain, the original plateau structure is destroyed, instead, the conductance exhibits new plateaus whose amplitude and position strongly depend on the strain strength and direction.

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38

Eskandari, Sina. "Cinematic Plateau and Sustainable Tourism". Studies in Media and Communication 5, n.º 2 (7 de septiembre de 2017): 39. http://dx.doi.org/10.11114/smc.v5i2.2640.

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When we are speaking about the cinematic plateau, cinematic natural landscapes or even the cinematic city, it means the locations outside the cinematic studios, the landscapes or locations which are set by a cinematographer in the background of his/her story.The cinematic plateau brings about sustainable tourism, because it does not need any specific season or special calendar and it is sufficient for the tourist to visit just the plateau and register the moment with the space.Producing film and registering the moments in special locations, the cinematographer unconsciously encourages the viewers to take a trip to the locations of shooting for recollection and to inject a new blood into the economic vessels of these regions.Focusing on the province of Almeria in Spain, this research is an attempt to learn about the cinematic plateaus, to introduce touristic spaces, to study how to attract cinematic tourists and to present new approaches for the dynamism of this industry.

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39

Bennett, David J., Yunru Li, Philip J. Harvey y Monica Gorassini. "Evidence for Plateau Potentials in Tail Motoneurons of Awake Chronic Spinal Rats With Spasticity". Journal of Neurophysiology 86, n.º 4 (1 de octubre de 2001): 1972–82. http://dx.doi.org/10.1152/jn.2001.86.4.1972.

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Motor units of segmental tail muscles were recorded in awake rats following acute (1–2 days) and chronic (>30 days) sacral spinal cord transection to determine whether plateau potentials contributed to sustained motor-unit discharges after injury. This study was motivated by a companion in vitro study that indicated that after chronic spinal cord injury, the tail motoneurons of the sacrocaudal spinal cord exhibit persistent inward currents ( I PIC) that cause intrinsically sustained depolarizations ( plateau potentials) and firing ( self-sustained firing). Importantly, in this companion study, the plateaus were fully activated at recruitment and subsequently helped sustain the firing without causing abrupt nonlinearities in firing. That is, after recruitment and plateau activation, the firing rate was modulated relatively linearly with injected current and therefore provided a good approximation of the input to the motoneuron despite the plateau. Thus in the present study, pairs of motor units were recorded simultaneously from the same muscle, and the firing rate ( F) of the lowest-threshold unit (control unit) was used as an estimate of the synaptic input to both units. We then examined whether firing of the higher-threshold unit (test unit) was intrinsically maintained by a plateau, by determining whether more synaptic input was required to recruit the test unit than to maintain its firing. The difference in the estimated synaptic input at recruitment and de-recruitment of the test unit (i.e., change in control unit rate, Δ F) was taken as an estimate of the plateau current ( I PIC) that intrinsically sustained the firing. Slowly graded manual skin stimulation was used to recruit and then de-recruit the units. The test unit was recruited when the control unit rate was on average 17.8 and 18.9 Hz in acute and chronic spinal rats, respectively. In chronic spinal rats, the test unit was de-recruited when the control unit rate (re: estimated synaptic input) was significantly reduced, compared with at recruitment (Δ F = −5.5 Hz), and thus a plateau participated in maintaining the firing. In the lowest-threshold motor units, even a brief stimulation triggered very long-lasting firing (seconds to hours; self-sustained firing). Higher-threshold units required continuous stimulation (or a spontaneous spasm) to cause firing, but again more synaptic input was needed to recruit the unit than to maintain its firing (i.e., plateau present). In contrast, in acute spinal rats, the stimulation did not usually trigger sustained motor-unit firing that could be attributed to plateaus because Δ F was not significantly different from zero. These results indicate that plateaus play an important role in sustaining motor-unit firing in awake chronic spinal rats and thus contribute to the hyperreflexia and hypertonus associated with chronic injury.

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40

O'Dwyer, Tony. "Plateau". Books Ireland, n.º 221 (1999): 112. http://dx.doi.org/10.2307/20631810.

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41

Knudson, Ruthann y Deward E. Walker. "Plateau". Journal of the Royal Anthropological Institute 5, n.º 4 (diciembre de 1999): 654. http://dx.doi.org/10.2307/2661181.

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42

Shabeer, Sobia, Shawn J. Mohammed, I. M. “Jim” Jawahar y Ahmad Raza Bilal. "The Mediating Influence of Fit Perceptions in the Relationship Between Career Adaptability and Job Content and Hierarchical Plateaus". Journal of Career Development 46, n.º 3 (13 de marzo de 2018): 332–45. http://dx.doi.org/10.1177/0894845318763960.

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Very little research has examined how career constructs are related to career plateaus. Given the dysfunctional consequences of plateauing, it is important to understand how career constructs, such as career adaptability, influence plateauing. Drawing on career construction theory and the theory of work adjustment, we propose that fit perceptions will mediate the career adaptability and plateauing relationship. Using data collected from 294 banking employees from the Punjab Province of Pakistan, we used the PROCESS macro to test for mediation. Results indicate that career adaptability reduces the likelihood of experiencing job content and hierarchical plateaus. Perceptions of fit related negatively to perceptions of plateauing, with one exception—demands–ability fit perceptions were unrelated to hierarchical plateaus. Mediation analysis indicated that needs–supply fit perceptions mediate the influence of career adaptability on both job content and hierarchical plateaus, whereas demands–ability fit perceptions mediate the influence of career adaptability on job content plateau but not hierarchical plateau. Implications of results for theory and practice are discussed.

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43

Santos, Fábio Luís de Souza, Antônio Felipe Couto Júnior, Adriana Reatto, Éder de Souza Martins, Arminda Moreira de Carvalho y Gabriela Bielefeld Nardoto. "Soil carbon and nitrogen under different land-use and landscape loca-tions in central Brazil". Journal of Biotechnology and Biodiversity 9, n.º 2 (12 de junio de 2021): 178–86. http://dx.doi.org/10.20873/jbb.uft.cemaf.v9n2.santos.

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In Central Brazil, plateaus, the most common geomorphologic form, have been undergoing intense conversion from native vegetation to pasture and agriculture in recent decades. We used carbon stable isotope ratios (δ13C) and nitrogen stable isotope ratios (δ15N) to assess possible changes in soil organic matter dynamics under such land use modifications. This study aimed to evaluate the differences in soil δ13C and δ15N and C and N stocks between native vegetation and agricultural or pasture areas in different locations of a plateau in the savannas of Central Brazil. We sampled soil up to 100 cm depth in pasture areas in the summit of the plateau and no-tillage and conventional tillage on the border of a plateau, as well as soils under native vegetation in both landscape locations. Both soil δ13C and δ15N, and C and N stocks showed no differences between land uses. The different relationships between δ15N and C/N ratio at different locations indicated distinct behavior of the soil organic matter between the summit and border of the plateau. Therefore, in addition to land-use, landscape location contributes to both δ13C and δ15N, and C and N stocks in the soil of the plateau.

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44

Major, Guy, Alon Polsky, Winfried Denk, Jackie Schiller y David W. Tank. "Spatiotemporally Graded NMDA Spike/Plateau Potentials in Basal Dendrites of Neocortical Pyramidal Neurons". Journal of Neurophysiology 99, n.º 5 (mayo de 2008): 2584–601. http://dx.doi.org/10.1152/jn.00011.2008.

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Glutamatergic inputs clustered over ∼20–40 μm can elicit local N-methyl-d-aspartate (NMDA) spike/plateau potentials in terminal dendrites of cortical pyramidal neurons, inspiring the notion that a single terminal dendrite can function as a decision-making computational subunit. A typical terminal basal dendrite is ∼100–200 μm long: could it function as multiple decision-making subunits? We test this by sequential focal stimulation of multiple sites along terminal basal dendrites of layer 5 pyramidal neurons in rat somatosensory cortical brain slices, using iontophoresis or uncaging of brief glutamate pulses. There was an approximately sevenfold spatial gradient in average spike/plateau amplitude measured at the soma, from ∼3 mV for distal inputs to ∼23 mV for proximal inputs. Spike/plateaus were NMDA receptor (NMDAR) conductance-dominated at all locations. Large Ca2+ transients accompanied spike/plateaus over a ∼10- to 40-μm zone around the input site; smaller Ca2+ transients extended approximately uniformly to the dendritic tip. Spike/plateau duration grew with increasing glutamate and depolarization; high Ca2+ zone size grew with spike/plateau duration. The minimum high Ca2+ zone half-width (just above NMDA spike threshold) increased from distal (∼10 μm) to proximal locations (∼25 μm), as did the NMDA spike glutamate threshold. Depolarization reduced glutamate thresholds. Simulations exploring multi-site interactions based on this demonstrate that if appropriately timed and localized inputs occur in vivo, a single basal dendrite could correspond to a cascade of multiple co-operating dynamic decision-making subunits able to retain information for hundreds of milliseconds, with increasing influence on neural output from distal to proximal. Dendritic NMDA spike/plateaus are thus well-suited to support graded persistent firing.

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45

Zheng, Tian-Ci, Da-Ming Wei, Yun Wang, Hao Zhou y Long Li. "Black Hole Activity Imprints on the Internal Plateau and the Subsequent Sharp Decay". Astrophysical Journal 964, n.º 2 (28 de marzo de 2024): 169. http://dx.doi.org/10.3847/1538-4357/ad234c.

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Abstract A stellar-mass black hole (BH) or a millisecond magnetar is believed to be born as the central engine of gamma-ray bursts (GRBs). The presence of plateaus in the X-ray extended emission or afterglow of GRBs is widely accepted as an indicator of a magnetar central engine, particularly those with a sharp decay (faster than t −3), the so-called internal plateau. However, an alternative model, by taking the evolution of the magnetic flux at the BH horizon into account, suggests that an internal plateau can also arise from a jet powered by the Blandford–Znajek (BZ) mechanism (hereafter, a BZ jet). In this study, we propose that a precessional BZ jet would manifest a quasiperiodic oscillation (QPO) signature on the internal plateau and the subsequent sharp decay. Such lightcurves cannot be readily explained by the activity of a short-lived, supermassive magnetar, thus favoring a Kerr BH as the central engine. The X-ray afterglow of GRB 050904, comprising nine flares, is characterized by a QPO-modulated plateau and sharp decay, which can be well reproduced by a precessional BZ jet model. Therefore, one potential clue for distinguishing between these two engines lies in whether the QPO signature is present throughout the entire plateau and the subsequent sharp decay, as the magnetar scenario suggests a collapse at the end of the plateau.

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46

Ma, Ruixue, Dacheng Wang, Ximin Cui, Xiaojing Yao, Shenshen Li, Hongsen Wang y Bingxuan Liu. "Distribution and Driving Force of Water Use Efficiency under Vegetation Restoration on the Loess Plateau". Remote Sensing 14, n.º 18 (9 de septiembre de 2022): 4513. http://dx.doi.org/10.3390/rs14184513.

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The Grain for Green Project (GGP) has considerably improved the vegetation cover of the Loess Plateau, as well as changed the carbon and water coupling process of local vegetation to a certain extent. Water use efficiency (WUE) is a crucial measure for evaluating ecosystem responses to global climate change and is a key indicator of the carbon–water coupling between terrestrial ecosystems and the environment. A comprehensive understanding of the impact of vegetation reconstruction on WUE on the Loess Plateau is of great significance to the vegetation growth and contribution to sustainable of the Loess Plateau. In recent years, scholars have gained a more comprehensive understanding of the distribution and drivers of WUE on the Loess Plateau. However, through the study of carbon and water coupling in the Loess Plateau, it is found that the effects of different vegetation restoration levels on WUE are still to be studied in depth in terms of spatial and temporal heterogeneity and long timeseries. In this paper, we analyzed the trends of Normalized Difference vegetation cover (NDVI) and WUE from 2001 to 2010 and 2011 to 2020, respectively, to research at the WUE of the vegetation in this area in relation to vegetation restoration. It was found that the Loess Plateau’s vegetation WUE rose from 2001 to 2020 at a rate of 0.023 g C kg−1 H2O per year, and that the increase from 2011 to 2020 was more significant than the growth from 2000 to 2010. The Loess Plateau’s area with a growing trend in vegetation water use rate increased from 77.12% in 2001–2010 to 88.63% in 2011–2020, with the majority of the increased area occurring in the northeastern Inner Mongolia region. After 20 years of the reforestation project, the area where NDVI and WUE increased simultaneously accounted for 71.54% of the Loess Plateau, the area where NDVI increased but WUE decreased accounted for 10.95% of the Loess Plateau, and the area where NDVI increased but WUE decreased accounted for 7.15% of the Loess Plateau. The correlation between temperature precipitation and WUE was not significant for the whole Loess Plateau, further indicating that the increase in vegetation cover was the main reason for the increase in vegetation water efficiency. Therefore, the effect of vegetation cover on WUE should be fully considered when vegetation restoration is carried out on the Loess Plateau.

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47

Zhao, Chen y Xiao-Shan Gao. "Analyzing the barren plateau phenomenon in training quantum neural networks with the ZX-calculus". Quantum 5 (4 de junio de 2021): 466. http://dx.doi.org/10.22331/q-2021-06-04-466.

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In this paper, we propose a general scheme to analyze the gradient vanishing phenomenon, also known as the barren plateau phenomenon, in training quantum neural networks with the ZX-calculus. More precisely, we extend the barren plateaus theorem from unitary 2-design circuits to any parameterized quantum circuits under certain reasonable assumptions. The main technical contribution of this paper is representing certain integrations as ZX-diagrams and computing them with the ZX-calculus. The method is used to analyze four concrete quantum neural networks with different structures. It is shown that, for the hardware efficient ansatz and the MPS-inspired ansatz, there exist barren plateaus, while for the QCNN ansatz and the tree tensor network ansatz, there exists no barren plateau.

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48

SARKAR, SUJIT. "EXCITATIONS OF A LOW-DIMENSIONAL DIMERIZED SPIN LADDER UNDER A MAGNETIC FIELD". International Journal of Modern Physics B 21, n.º 07 (20 de marzo de 2007): 1005–18. http://dx.doi.org/10.1142/s0217979207036801.

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Here we study the dimerized spin ladder with nearest-neighbor (J1) and next-nearest-neighbor (J2) anti-ferromagnetic interaction under a magnetic field. We predict the existence of different magnetization plateaus for the presence of spin-Peierls interaction on both J1 and J2. Magnetization plateau at m = 0 for J1 dimerization is spontaneous due to XY interaction, but it is absent for J2 dimerization, only intrinsic umklapp term leads to plateau (spin gap) state for some specific values of XXZ anisotropy (Δ) and J2. Here we predict a saturation plateau which is the classical phase of the system. There are some numerical support of our analytical approach already existing in the literature. The transition from commensurate gapped phase to incommensurate Luttinger liquid phase is the Mott-δ type of transition.

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49

Brouillet, Luc, Stuart Hay, Pierrette Turcotte y André Bouchard. "La flore vasculaire alpine du plateau Big Level, au parc national du Gros-Morne, Terre-Neuve". Géographie physique et Quaternaire 52, n.º 2 (2 de octubre de 2002): 175–94. http://dx.doi.org/10.7202/004774ar.

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Résumé La flore alpine du nord-est de l'Amérique du Nord est bien documentée à l'exception de celle des monts Long Range, à Terre-Neuve. Le plateau gneissique de Big Level est l'un des plus grands plateaux de haute altitude des monts Long Range. Parmi les habitats alpins qui s'y trouvent, les nombreuses combes à neige contribuent le plus à la biodiversité végétale avec 73 des 92 espèces observées à cet étage du plateau. Les 21 espèces rares observées sur le plateau appartiennent toutes à des habitats associés aux combes à neige. Ces espèces représen- tent 20 % des plantes rares connues dans le parc national du Gros-Morne, dont trois constituent des extensions méridionales de leur aire depuis l'extrémité nord de l'île : Carex lachenalii, Salix argyrocarpa et Veronica wormskjoldii . La composition biogéographique des combes à neige de la région du golfe du Saint-Laurent - Nouvelle-Angleterre, avec ses éléments circumpolaires, cordillériens, du nord-est de l'Amérique du Nord et amphi-atlantiques, contribue au caractère floristique exceptionnel du plateau. Le broutage intense des gazons périphériques par les importants troupeaux de caribous du plateau constitue une caractérisitique écologique intéressante de ces combes alpines. Également exceptionnelle est la présence de vastes landes à buttes dominées par la camarine et le calamagrostide ( Empetrum-Calamagrostis pickeringii ), les buttes étant causées par la cryoturbation sur les pentes douces exposées de la partie est du plateau. À notre connaissance, ce type de terrain réticulé, connu en Arctique, n'a pas été observé pour la zone boréale de l'est de l'Amérique du Nord ; c'est un témoin de la rigueur des hivers sur le plateau. Aucun autre plateau alpin gneissique de l'est de l'Amérique du Nord boréale n'a une telle étendue ni un tel nombre de combes à neige.

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Andjić, Goran, Peter O. Baumgartner y Claudia Baumgartner-Mora. "Collision of the Caribbean Large Igneous Province with the Americas: Earliest evidence from the forearc of Costa Rica". GSA Bulletin 131, n.º 9-10 (20 de marzo de 2019): 1555–80. http://dx.doi.org/10.1130/b35037.1.

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AbstractThe Cretaceous period was marked by the most voluminous episodes of oceanic plateau volcanism in the Phanerozoic Eon. Primarily affecting the Pacific, mantle plumes generated oceanic plateaus during three main phases (ca. 145–140 Ma, ca. 122–115 Ma, and ca. 100–90 Ma). Central America is one of the very few circum-Pacific margins where remnants of these Cretaceous plateaus were accreted. The study of their onland exposures provides a highly valuable insight into the complexity and diversity of oceanic plateau histories, from their eruption to their accretion. Exposed in northern Costa Rica, the plateau remnants of the Nicoya Peninsula originated from a Jurassic oceanic crust over-thickened by Early and Late Cretaceous hotspots. These sheared-off pieces of the Farallon Plate testify to the early tectonic interaction of the Caribbean Large Igneous Province (CLIP, ca. 94–89 Ma) with North America, initiated <5 m.y. after the onset of CLIP eruption. By combining our results with previously published data, we propose an updated tectono-stratigraphic framework that divides the Nicoya Peninsula into two oceanic plateau terranes. (1) The accretion timing of the Aptian to Turonian Manzanillo Terrane is constrained by the Coniacian (ca. 89–86 Ma) base of the overlapping Loma Chumico Formation. The proximal tuffaceous forearc deposits of the Loma Chumico Formation are the oldest evidence of a volcanic arc in Costa Rica—called here the Berrugate Arc—as revealed by new biostratigraphic and geochemical data. (2) The Nicoya Complex s. str. is a composite plateau remnant containing rocks of Bajocian to earliest Campanian age. Its accretion occurred during the middle Campanian (ca. 79–76 Ma) and shut down the Berrugate Arc. In contrast to the collision of CLIP with North America, onset of the collision of CLIP with South America began much later, during the latest Campanian (ca. 75–73 Ma).

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