37 research outputs found
Zero-forcing beamforming for physical layer security of energy harvesting wireless communications
Clinical efficacy of a combination of propofol and etomidate in pediatric anesthesia, and its effect on vital indices in patients
Purpose: To study the clinical effectiveness of a combination of propofol and etomidate as pediatric anesthesia, and its influence on some vital factors in the patients.Methods: A total of 104 children who underwent appendectomy, hepatobiliary surgery and excision of bone tumor in Xuzhou Children's Hospital, Xuzhou Medical University, Xuzhou, China from June 2018 to June 2020, were selected for this retrospective study. The patients were divided into groups A, B and C. In group A, 40 patients received the combination of propofol and etomidate, 32 patients received propofol only, while group C comprised 32 patients who received etomidate only. Vital indices such as anesthesia induction time, wake-up time after surgery, anesthetic effect, and adverse reactions were determined.Results: In group A, the mean arterial pressure (MAP) and heart rate (HR) were improved; anesthesia induction time and wake-up time after surgery were shorter, and anesthetic effect was more obvious in children with grades I and II. However, there was no grade III anesthetic effect, although there was a lower incidence of adverse reactions in this group.Conclusion: The use of a combination of propofol and etomidate results in higher clinical efficacy of pediatric anesthesia than either propofol or etomidate alone. Furthermore, the combination produces better quality of vital indices in the patients
Clinical efficacy of a combination of propofol and etomidate in pediatric anesthesia, and its effect on vital indices in patients
Purpose: To study the clinical effectiveness of a combination of propofol and etomidate as pediatricanesthesia, and its influence on some vital factors in the patients.Methods: A total of 104 children who underwent appendectomy, hepatobiliary surgery and excision ofbone tumor in Xuzhou Children's Hospital, Xuzhou Medical University, Xuzhou, China from June 2018 to June 2020, were selected for this retrospective study. The patients were divided into groups A, B and C. In group A, 40 patients received the combination of propofol and etomidate, 32 patients received propofol only, while group C comprised 32 patients who received etomidate only. Vital indices such asanesthesia induction time, wake-up time after surgery, anesthetic effect, and adverse reactions were determined.Results: In group A, the mean arterial pressure (MAP) and heart rate (HR) were improved; anesthesia induction time and wake-up time after surgery were shorter, and anesthetic effect was more obvious in children with grades I and II. However, there was no grade III anesthetic effect, although there was a lower incidence of adverse reactions in this group.Conclusion: The use of a combination of propofol and etomidate results in higher clinical efficacy of pediatric anesthesia than either propofol or etomidate alone. Furthermore, the combination produces better quality of vital indices in the patient
Seasonal overturning circulation in the Red Sea : 2. Winter circulation
Author Posting. ©0American Geophysical Union, 2014. This article is posted here by permission of [American Geophysical Union for personal use, not for redistribution. The definitive version was published in Journal of Geophysical Research: Oceans 119 (2014): 2263–2289, doi:10.1002/2013JC009331.The shallow winter overturning circulation in the Red Sea is studied using a 50 year high-resolution MITgcm (MIT general circulation model) simulation with realistic atmospheric forcing. The overturning circulation for a typical year, represented by 1980, and the climatological mean are analyzed using model output to delineate the three-dimensional structure and to investigate the underlying dynamical mechanisms. The horizontal model circulation in the winter of 1980 is dominated by energetic eddies. The climatological model mean results suggest that the surface inflow intensifies in a western boundary current in the southern Red Sea that switches to an eastern boundary current north of 24°N. The overturning is accomplished through a cyclonic recirculation and a cross-basin overturning circulation in the northern Red Sea, with major sinking occurring along a narrow band of width about 20 km along the eastern boundary and weaker upwelling along the western boundary. The northward pressure gradient force, strong vertical mixing, and horizontal mixing near the boundary are the essential dynamical components in the model's winter overturning circulation. The simulated water exchange is not hydraulically controlled in the Strait of Bab el Mandeb; instead, the exchange is limited by bottom and lateral boundary friction and, to a lesser extent, by interfacial friction due to the vertical viscosity at the interface between the inflow and the outflow.Partial support for this effort was
provided by the Saudi Aramco Marine
Environmental Research Center at
KAUST.2014-10-1
Zero-forcing beamforming for physical layer security of energy harvesting wireless communications
In Vivo Near-Infrared Imaging of Fibrin Deposition in Thromboembolic Stroke in Mice
imaging of activated factor XIII (FXIIIa), an important mediator of thrombosis or fibrinolytic resistance. The present study was to investigate the fibrin deposition in a thromboembolic stroke mice model by FXIIIa–targeted near-infrared fluorescence (NIRF) imaging., which were correlated with histology after animal euthanasia. NIRF images and lesion volume.Non-invasive detection of fibrin deposition in ischemic mouse brain using NIRF imaging is feasible and this technique may provide an in vivo experimental tool in studying the role of fibrin in stroke
Towards an end-to-end analysis and prediction system for weather, climate, and marine applications in the Red Sea
Author Posting. © American Meteorological Society, 2021. This article is posted here by permission of American Meteorological Society for personal use, not for redistribution. The definitive version was published in Bulletin of the American Meteorological Society 102(1), (2021): E99-E122, https://doi.org/10.1175/BAMS-D-19-0005.1.The Red Sea, home to the second-longest coral reef system in the world, is a vital resource for the Kingdom of Saudi Arabia. The Red Sea provides 90% of the Kingdom’s potable water by desalinization, supporting tourism, shipping, aquaculture, and fishing industries, which together contribute about 10%–20% of the country’s GDP. All these activities, and those elsewhere in the Red Sea region, critically depend on oceanic and atmospheric conditions. At a time of mega-development projects along the Red Sea coast, and global warming, authorities are working on optimizing the harnessing of environmental resources, including renewable energy and rainwater harvesting. All these require high-resolution weather and climate information. Toward this end, we have undertaken a multipronged research and development activity in which we are developing an integrated data-driven regional coupled modeling system. The telescopically nested components include 5-km- to 600-m-resolution atmospheric models to address weather and climate challenges, 4-km- to 50-m-resolution ocean models with regional and coastal configurations to simulate and predict the general and mesoscale circulation, 4-km- to 100-m-resolution ecosystem models to simulate the biogeochemistry, and 1-km- to 50-m-resolution wave models. In addition, a complementary probabilistic transport modeling system predicts dispersion of contaminant plumes, oil spill, and marine ecosystem connectivity. Advanced ensemble data assimilation capabilities have also been implemented for accurate forecasting. Resulting achievements include significant advancement in our understanding of the regional circulation and its connection to the global climate, development, and validation of long-term Red Sea regional atmospheric–oceanic–wave reanalyses and forecasting capacities. These products are being extensively used by academia, government, and industry in various weather and marine studies and operations, environmental policies, renewable energy applications, impact assessment, flood forecasting, and more.The development of the Red Sea modeling system is being supported by the Virtual Red Sea Initiative and the Competitive Research Grants (CRG) program from the Office of Sponsored Research at KAUST, Saudi Aramco Company through the Saudi ARAMCO Marine Environmental Center at KAUST, and by funds from KAEC, NEOM, and RSP through Beacon Development Company at KAUST
Recommended from our members
Water Mass Formation and Circulation in the Persian Gulf and Water Exchange with the Indian Ocean
The Persian Gulf is a shallow, semi-enclosed marginal sea where the Persian Gulf Water (PGW), one of the most saline water masses in the world, is formed due to the arid climate. The PGW flushes out of the Persian Gulf as a deep outflow and induces a surface inflow of the Indian Ocean Surface Water (IOSW), driving an inverse-estuarine type water exchange through the Strait of Hormuz. In this dissertation, the circulation and water mass transformation processes in the Persian Gulf and the water exchange with the Indian Ocean through the Strait of Hormuz, in response to the atmospheric forcing, are studied using the HYbrid Coordinate Ocean Model (HYCOM). The model is driven by surface wind stress, heat and fresh water fluxes derived from two sources: the COADS (Comprehensive Ocean-Atmosphere Data Set) monthly climatology and high frequency (2-hourly) MM5 (The Fifth-Generation NCAR/Penn State Mesoscale Model) output. This study is motivated by the time series measurements in the Strait during December 1996 to March 1998 by Johns et al. (2003), which also serve as a major benchmark for evaluating the model results. The simulations with climatological forcing show that the IOSW propagates in two branches into the Gulf, one along the Iranian coast toward the northern gulf and the other one onto the southern banks driven by the Ekman drift by the prevailing northwesterly winds. These two branches of inflow form two cyclonic gyres in the northern and in the southern gulf respectively. Cold, saline deep waters are formed both in the northern gulf and in the southern gulf during the wintertime cooling period and their exports contribute seasonally to the outflow in the strait. After formation in winter, the dense water in the shallow southwestern gulf spills off into the strait and causes high-salinity pulses in the outflow in the strait, a phenomenon also present in the observations. The export of dense waters from the northern gulf persists throughout the year, with the largest cold water export in summer. The intrusion of the IOSW in the model extends much farther into the Gulf in summer than in winter, which is in agreement with observations. By analyzing the salt balance in the basin and conducting sensitivity experiments, we show that it is the balance between the advection of IOSW and vertical upward flux induced by vertical mixing that mainly controls the seasonal variation of the surface salinity. The surface salinity in winter is increased by upward mixing from saltier subsurface waters, which is caused by the strong vertical mixing condition maintained by the surface heat loss. Surface wind stress, which opposes the inflow and is stronger in winter than in summer, plays a secondary role in modulating the seasonal intrusion of the IOSW. The MM5 high frequency forcing, capable of resolving synoptic weather events, leads to increased heat loss in winter, enhanced vertical mixing and higher annual mean evaporation rate. In the simulation with the high frequency forcing, the waters in the gulf are generally about 3 degree C colder and 1 psu fresher than with COADS forcing, and agree better with observations. The high-frequency forcing has little effect on the export of the dense waters from the northern gulf but delays the spillage of the waters from the southern gulf to April. A notable synoptic feature of the simulations is the annual appearance of eddies along the intruding salinity front. The typical sizes of the fully developed eddies in summer are about 100 km, about 3 times of the local Rossby deformation radius, consistent with a baroclinic instability process. The existence of these eddies is confirmed in satellite images of surface temperature in the Gulf
Relationship of the Warming of Red Sea Surface Water over 140 Years with External Heat Elements
Using historic data, variations in the sea surface temperature (SST), sea surface air temperature, and air–sea heat flux of the Red Sea and its adjacent seas over 140 years (1876–2019) as well as correlations of these variations were statistically analyzed. The results show that the SST of the Red Sea increased at a mean rate of 0.043 °C/decade in these years with an accelerated rate in recent decades, and the SST anomalies of the sea had significant positive correlations and high synchronisms with those of adjacent seas as well as air temperature anomalies. In this period, the Red Sea lost more heat to the air via evaporation due to water warming and gained more heat from the Gulf of Aden. The analysis revealed that the temperature rise in the Red Sea surface water was directly caused by the horizontal heat input from the upper warming water of the Gulf of Aden under the circumstance of global ocean warming, rather than by the rise in local air temperature. However, in recent decades, the accelerated rise in air temperature over the sea has decreased the sensible heat flux, which might contribute to the Red Sea warming
Rapid Red Sea Deep Water renewals caused by volcanic eruptions and the North Atlantic Oscillation
The Red Sea hosts a deep marine environment unique among the world’s oceans. It is occupied, almost homogeneously from the subsurface (~137 to 300 m) to depths over 2000 m, by a warm (~21.5°C) and highly saline (~40.5) water mass, referred to as the Red Sea Deep Water (RSDW). Previous studies suggested that the RSDW is mainly ventilated, continuously or intermittently, by dense outflows from the northern Gulfs of Suez and Aqaba with a resulting sluggish renewal time on the order of 36 to 90 years. We use six repeated hydrographic observations spanning the period 1982–2011 and simulations of an ocean general circulation model with realistic atmospheric forcing to show that large portions of the RSDW were episodically replaced during 1982–2001 by new dense waters mainly formed by open-ocean deep convections in the northern Red Sea during anomalously cold winters, pointing to a much shorter renewal time for the RSDW on the order of a decade. We further show that the winter cooling anomaly in the Red Sea region was a part of a large-scale climate variability pattern associated with either large volcanic eruptions or the North Atlantic Oscillation (NAO). Consequently, significant deep water formation events occurred in the Red Sea in the winters following the 1982 El Chichón eruption in Mexico and the 1991 Mount Pinatubo eruption in the Philippines and during the strong positive phase of the NAO in the winter of 198