scholarly journals The Dominant Role of the East Siberian Sea in Driving the Oceanic Flow Through the Bering Strait—Conclusions From GRACE Ocean Mass Satellite Data and In Situ Mooring Observations Between 2002 and 2016

2017 ◽  
Vol 44 (22) ◽  
pp. 11,472-11,481 ◽  
Author(s):  
Cecilia Peralta‐Ferriz ◽  
Rebecca A. Woodgate
2016 ◽  
Vol 2016 ◽  
pp. 1-11 ◽  
Author(s):  
Yong Peng Yu ◽  
Lan Tan

Accurate definition and better understanding of the mechanisms of stroke are crucial as this will guide the effective care and therapy. In this paper, we review the previous basic and clinical researches on the causes or mechanisms of ischemic cerebrovascular diseases (ICVD) and interpret the correlation between embolism and hypoperfusion based on vascular stenosis and arterial intimal lesions. It was suggested that if there is no embolus (dynamic or in situ emboli), there might be no cerebral infarction. Three kinds of different clinical outcomes of TIA were theoretically interpreted based on its mechanisms. We suppose that there is a correlation between embolism and hypoperfusion, and which mechanisms (hypoperfusion or hypoperfusion induced microemboli) playing the dominant role in each type of ICVD depends on the unique background of arterial intimal lesions (the vulnerability of vessels). That is to say, the vulnerability of vessels is involved in the role of embolism and hypoperfusion in the mechanisms of ischemic cerebrovascular diseases. This inference might enrich and provide better understandings for the underlying etiologies of ischemic cerebrovascular events.


2008 ◽  
Vol 142 (1-2) ◽  
pp. 32-39 ◽  
Author(s):  
Anthony E. Pickering ◽  
Annabel E. Simms ◽  
Julian F.R. Paton

Metals ◽  
2020 ◽  
Vol 10 (4) ◽  
pp. 482
Author(s):  
Efraín Hernández-Rivera ◽  
Sean J. Fudger ◽  
B. Chad Hornbuckle ◽  
Anthony J. Roberts ◽  
Kristopher A. Darling

The role of kinetically and thermodynamically driven microstructural evolution on FeNiZr was explored through in situ XRD analysis. A statistical approach based on log-likelihoods and composite link model was used to fit and extract important data from the XRD patterns. Best practices on using the statistical approach to obtained quantitative information from the XRD patterns was presented. It was shown that the alloyed powder used in the current study presents more thermodynamic stability than previously reported ball-milled powders. Based on hardness values, it was shown that mechanical strength is expected to be retained at higher processing temperatures. Lastly, a 2-dimensional heat transfer model was used to understand heat flow through the powder compacts.


2014 ◽  
Vol 306 (1) ◽  
pp. L50-L57 ◽  
Author(s):  
Mohammad N. Islam ◽  
Galina A. Gusarova ◽  
Eiji Monma ◽  
Shonit R. Das ◽  
Jahar Bhattacharya

Alveolar type 2 (AT2) cells secrete surfactant that forms a protective layer on the lung's alveolar epithelium. Vesicles called lamellar bodies (LBs) store surfactant. Failure of surfactant secretion, which causes severe lung disease, relates to the manner in which LBs undergo exocytosis during the secretion. However, the dynamics of LBs during the secretion process are not known in intact alveoli. Here, we addressed this question through real-time confocal microscopy of single AT2 cells in live alveoli of mouse lungs. Using a combination of phospholipid and aqueous fluorophores that localize to LBs, we induced surfactant secretion by transiently hyperinflating the lung, and we quantified the secretion in terms of loss of bulk LB fluorescence. In addition, we quantified inter-LB phospholipid flow through determinations of fluorescence recovery after photobleaching. Furthermore, we determined the role of F-actin in surfactant secretion through expression of the fluorescent F-actin probe Lifeact. Our findings indicate that, in AT2 cells in situ, LBs are held in an F-actin scaffold. Although F-actin transiently decreases during surfactant secretion, the LBs remain stationary, forming a chain of vesicles connected by intervesicular channels that convey surfactant to the secretion site on the plasma membrane. This is the first instance of a secretory process in which the secretory vesicles are immobile, but form a conduit for the secretory material.


Author(s):  
Yuanyuan Zhang ◽  
Ping Guo ◽  
Siwei Li ◽  
Jianmin Sun ◽  
Wei Wang ◽  
...  

The dominant role of the magnetoresistance effect caused by spin electron scattering in the oxygen evolution reaction is unveiled through an in situ tunable magnetic field-electrochemical testing system.


Author(s):  
Mengjie Hou ◽  
Baoxing Tian ◽  
Baoshuai Bai ◽  
Zheng Ci ◽  
Yu Liu ◽  
...  

2011 ◽  
Vol 20 (01) ◽  
pp. 95-103 ◽  
Author(s):  
S. OKTYABRSKY ◽  
P. NAGAIAH ◽  
V. TOKRANOV ◽  
M. YAKIMOV ◽  
R. KAMBHAMPATI ◽  
...  

Hall electron mobility in buried QW InGaAs channels, grown on InP substrates with HfO 2 gate oxide, is analyzed experimentally and theoretically as a function of top barrier thickness and composition, carrier density, and temperature. Temperature slope α in μ ~Tα dependence is changing from α=-1.1 to +1 with the reduction of the top barrier thickness indicating the dominant role of remote Coulomb scattering (RCS) in interface-related contribution to mobility degradation. Insertion of low-k SiO x interface layer formed by oxidation of thin in-situ MBE grown amorphous Si passivation layer has been found to improve the channel mobility, but at the expense of increased EOT. This mobility improvement is also consistent with dominant role of RCS. We were able to a obtain a reasonable match between experiment and simple theory of the RCS assuming the density of charges at the high-k/barrier interface to be in the range of (2-4)×1013 cm-2.


1989 ◽  
Vol 256 (6) ◽  
pp. F1027-F1033
Author(s):  
T. C. Welbourne

The flux of glutamine through cellular PDG or extracellular gamma-glutamyltransferase may reflect competition between the membrane glutamine transporter and extracellular hydrolysis. To test this model, kidneys from nonacidotic (NA) and chronically acidotic rats were isolated and perfused with glutamine in a Na+ media and then with a media in which choline replaced Na+. Replacing Na+ abolished the Na+ gradient and completely eliminated the transport of filtered glutamine back into the perfusate. Nevertheless NH4+ production and glutamine utilization remained intact while glutamate accumulated in the extracellular compartments. In the Na+ media, acidotic rat kidneys produced 2.6 times more NH4+ and utilized 1.5-fold more glutamine than their NA counterparts. In the choline media, acidotic rat kidneys had a large drop in NH4+ production but not in glutamine utilization; associated with this was a large glutamate accumulation in the extracellular compartments consistent with flow through the extracellular pathway. To demonstrate the applicability of this model, the role of the adrenals and glucocorticoids in modulating fluxes over these pathways was studied. Kidneys from adrenalectomized acidotic rats exhibited a diminished transport of glutamine, reduced utilization and decreased ammoniagenesis; glutamate accumulation in the extracellular compartment rose consistent with greater flux via the extracellular glutaminase. Supplementing these animals with triamcinolone restored flow into the cellular pathway. The results confirm the in situ activity of two renal glutaminases whose relative contributions to renal ammoniagenesis are dependent on the acid base balance, glucocorticoids, and the existing Na+ gradient.


2005 ◽  
Vol 891 ◽  
Author(s):  
Mahesh Kumar ◽  
Vinod Kumar Paliwal ◽  
Govind ◽  
A. G. Vedeshwar ◽  
S. M. Shivaprasad

ABSTRACTThe adsorption of Sb on the high index Si (5 5 12) has been studied at higher substrate temperature (HT) (800°C), using in situ surface characterization techniques like Auger Electron Spectroscopy (AES), Low Energy Electron Diffraction (LEED), and Electron Energy Loss Spectroscopy (EELS). The surface morphology of this high index Si (5 5 12) surface has row like trenches along (110) direction. We have performed the study of Sb adsorption and desorption on the Si (5 5 12) substrate held at different temperatures. The different pathways adopted during adsorption and desorption have suggested the dominant role of kinetics I forming various surface phases on the Si (5 5 12) substrate. The adsorption at room temperature resulted in the formation of (225) surface phase, while the adsorption at 680°C resulted in the (337) phase. The sequential thermal desorption of the room temperature and high temperature adsorbed surface resulted in the formation of (337) phases at 800°C, with anisotropic growth along one direction. While the adsorption at 800°C resulted in the formation of anisotropic (337) like phases, the further increase in the coverage formed a 2x Si (225) phase. Annealing this 2x Si (225) phase again resulted in the formation of anisotropic (337) phase. Thus formation of interface by controlling the growth kinetics can result in the formation of various tailored structures with desired properties.


2021 ◽  
Author(s):  
Yajing Zheng ◽  
Shuang Wu ◽  
Shuqi Xiao ◽  
Kai Yu ◽  
Xiantao Fang ◽  
...  

Abstract Non-marine waters (i.e., rivers, reservoirs, lakes, ponds, streams and estuaries) are globally significant emitters of methane (CH4) and nitrous oxide (N2O) to the atmosphere, while global estimates of these emissions have been hampered due to the lack of a worldwide comprehensive database with the collection of complete CH4 and N2O flux components. Here we synthesize 2997 in-situ flux or concentration measurements of CH4 and N2O from 277 peer-reviewed publications to examine the role of non-marine waters in shaping climate change. Here we estimate that inland waters including rivers, reservoirs, lakes and streams together release 94.49 Tg CH4 yr− 1 (ebullition plus diffusion) and 1.52 Tg N2O yr− 1 (diffusion) to the atmosphere, yielding an overall CO2-equivalent emission total of 3.05 Pg CO2 yr− 1, representing roughly 59% of CO2 emissions (5.13 Pg CO2 yr− 1) from these four aquatic ecosystems, with lakes acting as the largest emitter for both trace gases. Ebullition is noticed as a dominant flux component, contributing up to 62–84% of total CH4 fluxes across all inland waters. Chamber-derived CH4 flux rates are significantly greater than those determined by diffusion model-based methods for commonly capturing of both diffusive and ebullitive fluxes. The synthesis of global N2O measurements projected that rivers exhibit the highest indirect N2O emission factor (EF5, 0.028%), while streams have the lowest EF5 value (0.015%). Our study reveals a major oversight in regional and global CH4 budgets from inland waters, caused by neglect of the dominant role of ebullition pathways in those emissions. The indirect EF5 values established in this study generally suggest an order of magnitude downward revision is required in current IPCC default EF5 values for inland waters and estuaries. Our findings further indicate that a comprehensive understanding of the magnitude and patterns of CH4 and N2O emissions from non-marine waters is essential in defining the way that these natural ecosystems shape our climate.


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