The Potential of Wetlands in Reducing Storm Surge

DTIC Science & Technology

2010-01-01

threatened by erosion and damage due to storm waves, wind, and surge. The risk of damage and loss of life is exacerbated by many factors, including coastal...obtained when attempting to correlate hurricane translation speed, surge hydrograph at the coast, and surge elevations inland. However, a trend was...greater surface roughness. In addition to reducing wind speeds, the models eliminate the wind stress in forested wetlands which inhibit wind from

Using wind setdown and storm surge on Lake Erie to calibrate the air-sea drag coefficient.

PubMed

Drews, Carl

2013-01-01

The air-sea drag coefficient controls the transfer of momentum from wind to water. In modeling storm surge, this coefficient is a crucial parameter for estimating the surge height. This study uses two strong wind events on Lake Erie to calibrate the drag coefficient using the Coupled Ocean Atmosphere Wave Sediment Transport (COAWST) modeling system and the the Regional Ocean Modeling System (ROMS). Simulated waves are generated on the lake with Simulating WAves Nearshore (SWAN). Wind setdown provides the opportunity to eliminate wave setup as a contributing factor, since waves are minimal at the upwind shore. The study finds that model results significantly underestimate wind setdown and storm surge when a typical open-ocean formulation without waves is used for the drag coefficient. The contribution of waves to wind setdown and storm surge is 34.7%. Scattered lake ice also increases the effective drag coefficient by a factor of 1.1.

Hot gas ingestion effects on fuel control surge recovery and AH-1 rotor drive train torque spikes

NASA Technical Reports Server (NTRS)

Tokarski, Frank; Desai, Mihir; Books, Martin; Zagranski, Raymond

1994-01-01

This report summarizes the work accomplished through computer simulation to understand the impact of the hydromechanical turbine assembly (TA) fuel control on rocket gas ingestion induced engine surges on the AH-1 (Cobra) helicopter. These surges excite the lightly damped torsional modes of the Cobra rotor drive train and can cause overtorqueing of the tail rotor shaft. The simulation studies show that the hydromechanical TA control has a negligible effect on drive train resonances because its response is sufficiently attenuated at the resonant frequencies. However, a digital electronic control working through the TA control's separate, emergency fuel metering system has been identified as a solution to the overtorqueing problem. State-of-the-art software within the electronic control can provide active damping of the rotor drive train to eliminate excessive torque spikes due to any disturbances including engine surges and aggressive helicopter maneuvers. Modifications to the existing TA hydromechanical control are relatively minor, and existing engine sensors can be utilized by the electronic control. Therefore, it is concluded that the combination of full authority digital electronic control (FADEC) with hydromechanical backup using the existing TA control enhances flight safety, improves helicopter performance, reduces pilot workload, and provides a substantial payback for very little investment.

From Hospital to Nursing Facility: Factors Influencing Decisions

ERIC Educational Resources Information Center

Mason, Susan E.; Auerbach, Charles; LaPorte, Heidi Heft

2009-01-01

This study addresses the factors influencing decisions to send medicine-surgical (med-surg) patients home or to nursing facilities (NFs). The sample (n = 7,852) was taken from a large, urban, teaching, med-surg unit where discharges were documented and data collected over a two-and-a-half-year period. Using logistical regression, the factors found…

The optimization of design parameters for surge relief valve for pipeline systems

NASA Astrophysics Data System (ADS)

Kim, Hyunjun; Hur, Jisung; Kim, Sanghyun

2017-06-01

Surge is an abnormal pressure which induced by rapid changes of flow rate in pipeline systems. In order to protect pipeline system from the surge pressure, various hydraulic devices have been developed. Surge-relief valve(SRV) is one of the widely applied devices to control surge due to its feasibility in application, efficiency and cost-effectiveness. SRV is designed to automatically open under abnormal pressure and discharge the flow and makes pressure of the system drop to the allowable level. The performance of the SRV is influenced by hydraulics. According to previous studies, there are several affecting factors which determine performance of the PRV such as design parameters (e.g. size of the valve), system parameters (e.g. number of the valves and location of the valve), and operation parameters (e.g. set point and operation time). Therefore, the systematic consideration for factors affecting performance of SRV is required for the proper installation of SRV in the system. In this study, methodology for finding optimum parameters of the SRV is explored through the integration of Genetic Algorithm(GA) into surge analysis.

Effect of azilsartan versus candesartan on morning blood pressure surges in Japanese patients with essential hypertension

PubMed Central

Kario, Kazuomi; Enya, Kazuaki; Sugiura, Kenkichi; Ikeda, Yoshinori

2014-01-01

Morning blood pressure (BP) surge is reported as a risk factor for cardiovascular events and end-organ damage independent of the 24-h BP level. Controlling morning BP surge is therefore important to help prevent onset of cardiovascular disease. We compared the efficacy of azilsartan and candesartan in controlling morning systolic BP (SBP) surges by analyzing relevant ambulatory BP monitoring data in patients with/without baseline BP surges. As part of a 16-week randomized, double-blind study of azilsartan (20–40 mg once daily) and candesartan (8–12 mg once daily) in Japanese patients with essential hypertension, an exploratory analysis was carried out using ambulatory BP monitoring at baseline and week 14. The effects of study drugs on morning BP surges, including sleep trough surge (early morning SBP minus the lowest night-time SBP) and prewaking surge (early morning SBP minus SBP before awakening), were evaluated. Patients with sleep trough surge of at least 35 mmHg were defined by the presence of a morning BP surge (the ‘surge group’). Sleep trough surge and prewaking surge data were available at both baseline and week 14 in 548 patients, 147 of whom (azilsartan 76; candesartan 71) had a baseline morning BP surge. In surge group patients, azilsartan significantly reduced both the sleep trough surge and the prewaking surge at week 14 compared with candesartan (least squares means of the between-group differences −5.8 mmHg, P=0.0395; and −5.7 mmHg, P=0.0228, respectively). Once-daily azilsartan improved sleep trough surge and prewaking surge to a greater extent than candesartan in Japanese patients with grade I–II essential hypertension. PMID:24710336

Effect of azilsartan versus candesartan on morning blood pressure surges in Japanese patients with essential hypertension.

PubMed

Rakugi, Hiromi; Kario, Kazuomi; Enya, Kazuaki; Sugiura, Kenkichi; Ikeda, Yoshinori

2014-06-01

Morning blood pressure (BP) surge is reported as a risk factor for cardiovascular events and end-organ damage independent of the 24-h BP level. Controlling morning BP surge is therefore important to help prevent onset of cardiovascular disease. We compared the efficacy of azilsartan and candesartan in controlling morning systolic BP (SBP) surges by analyzing relevant ambulatory BP monitoring data in patients with/without baseline BP surges. As part of a 16-week randomized, double-blind study of azilsartan (20-40 mg once daily) and candesartan (8-12 mg once daily) in Japanese patients with essential hypertension, an exploratory analysis was carried out using ambulatory BP monitoring at baseline and week 14. The effects of study drugs on morning BP surges, including sleep trough surge (early morning SBP minus the lowest night-time SBP) and prewaking surge (early morning SBP minus SBP before awakening), were evaluated. Patients with sleep trough surge of at least 35 mmHg were defined by the presence of a morning BP surge (the 'surge group'). Sleep trough surge and prewaking surge data were available at both baseline and week 14 in 548 patients, 147 of whom (azilsartan 76; candesartan 71) had a baseline morning BP surge. In surge group patients, azilsartan significantly reduced both the sleep trough surge and the prewaking surge at week 14 compared with candesartan (least squares means of the between-group differences -5.8 mmHg, P=0.0395; and -5.7 mmHg, P=0.0228, respectively). Once-daily azilsartan improved sleep trough surge and prewaking surge to a greater extent than candesartan in Japanese patients with grade I-II essential hypertension.

Bridging complexity theory and resilience to develop surge capacity in health systems.

PubMed

Therrien, Marie-Christine; Normandin, Julie-Maude; Denis, Jean-Louis

2017-03-20

Purpose Health systems are periodically confronted by crises - think of Severe Acute Respiratory Syndrome, H1N1, and Ebola - during which they are called upon to manage exceptional situations without interrupting essential services to the population. The ability to accomplish this dual mandate is at the heart of resilience strategies, which in healthcare systems involve developing surge capacity to manage a sudden influx of patients. The paper aims to discuss these issues. Design/methodology/approach This paper relates insights from resilience research to the four "S" of surge capacity (staff, stuff, structures and systems) and proposes a framework based on complexity theory to better understand and assess resilience factors that enable the development of surge capacity in complex health systems. Findings Detailed and dynamic complexities manifest in different challenges during a crisis. Resilience factors are classified according to these types of complexity and along their temporal dimensions: proactive factors that improve preparedness to confront both usual and exceptional requirements, and passive factors that enable response to unexpected demands as they arise during a crisis. The framework is completed by further categorizing resilience factors according to their stabilizing or destabilizing impact, drawing on feedback processes described in complexity theory. Favorable order resilience factors create consistency and act as stabilizing forces in systems, while favorable disorder factors such as diversity and complementarity act as destabilizing forces. Originality/value The framework suggests a balanced and innovative process to integrate these factors in a pragmatic approach built around the fours "S" of surge capacity to increase health system resilience.

Selection of gonadotrophin surge attenuating factor phage antibodies by bioassay

PubMed Central

Sorsa-Leslie, Tarja; Mason, Helen D; Harris, William J; Fowler, Paul A

2005-01-01

Background We aimed to combine the generation of "artificial" antibodies with a rat pituitary bioassay as a new strategy to overcome 20 years of difficulties in the purification of gonadotrophin surge-attenuating factor (GnSAF). Methods A synthetic single-chain antibody (Tomlinson J) phage display library was bio-panned with partially purified GnSAF produced by cultured human granulosa/luteal cells. The initial screening with a simple binding immunoassay resulted in 8 clones that were further screened using our in-vitro rat monolayer bioassay for GnSAF. Initially the antibodies were screened as pooled phage forms and subsequently as individual, soluble, single-chain antibody (scAbs) forms. Then, in order to improve the stability of the scAbs for immunopurification purposes, and to widen the range of labelled secondary antibodies available, these were engineered into full-length human immunoglobulins. The immunoglobulin with the highest affinity for GnSAF and a previously described rat anti-GnSAF polyclonal antiserum was then used to immunopurify bioactive GnSAF protein. The two purified preparations were electrophoresed on 1-D gels and on 7 cm 2-D gels (pH 4–7). The candidate GnSAF protein bands and spots were then excised for peptide mass mapping. Results Three of the scAbs recognised GnSAF bioactivity and subsequently one clone of the purified scAb-derived immunoglobulin demonstrated high affinity for GnSAF bioactivity, also binding the molecule in such as way as to block its bioactivity. When used for repeated immunopurification cycles and then Western blot, this antibody enabled the isolation of a GnSAF-bioactive protein band at around 66 kDa. Similar results were achieved using the rat anti-GnSAF polyclonal antiserum. The main candidate molecules identified from the immunopurified material by excision of 2-D gel protein spots was human serum albumin precursor and variants. Conclusion This study demonstrates that the combination of bioassay and phage display technologies is a powerful tool in the study of uncharacterised proteins that defy conventional approaches. In addition, we conclude that these data support suggestions that GnSAF may be structurally related to serum albumin or very tightly bound to serum albumin. PMID:16185358

Selection of gonadotrophin surge attenuating factor phage antibodies by bioassay.

PubMed

Sorsa-Leslie, Tarja; Mason, Helen D; Harris, William J; Fowler, Paul A

2005-09-26

We aimed to combine the generation of "artificial" antibodies with a rat pituitary bioassay as a new strategy to overcome 20 years of difficulties in the purification of gonadotrophin surge-attenuating factor (GnSAF). A synthetic single-chain antibody (Tomlinson J) phage display library was bio-panned with partially purified GnSAF produced by cultured human granulosa/luteal cells. The initial screening with a simple binding immunoassay resulted in 8 clones that were further screened using our in-vitro rat monolayer bioassay for GnSAF. Initially the antibodies were screened as pooled phage forms and subsequently as individual, soluble, single-chain antibody (scAbs) forms. Then, in order to improve the stability of the scAbs for immunopurification purposes, and to widen the range of labelled secondary antibodies available, these were engineered into full-length human immunoglobulins. The immunoglobulin with the highest affinity for GnSAF and a previously described rat anti-GnSAF polyclonal antiserum was then used to immunopurify bioactive GnSAF protein. The two purified preparations were electrophoresed on 1-D gels and on 7 cm 2-D gels (pH 4-7). The candidate GnSAF protein bands and spots were then excised for peptide mass mapping. Three of the scAbs recognised GnSAF bioactivity and subsequently one clone of the purified scAb-derived immunoglobulin demonstrated high affinity for GnSAF bioactivity, also binding the molecule in such as way as to block its bioactivity. When used for repeated immunopurification cycles and then Western blot, this antibody enabled the isolation of a GnSAF-bioactive protein band at around 66 kDa. Similar results were achieved using the rat anti-GnSAF polyclonal antiserum. The main candidate molecules identified from the immunopurified material by excision of 2-D gel protein spots was human serum albumin precursor and variants. This study demonstrates that the combination of bioassay and phage display technologies is a powerful tool in the study of uncharacterised proteins that defy conventional approaches. In addition, we conclude that these data support suggestions that GnSAF may be structurally related to serum albumin or very tightly bound to serum albumin.

Using Wind Setdown and Storm Surge on Lake Erie to Calibrate the Air-Sea Drag Coefficient

PubMed Central

Drews, Carl

2013-01-01

The air-sea drag coefficient controls the transfer of momentum from wind to water. In modeling storm surge, this coefficient is a crucial parameter for estimating the surge height. This study uses two strong wind events on Lake Erie to calibrate the drag coefficient using the Coupled Ocean Atmosphere Wave Sediment Transport (COAWST) modeling system and the the Regional Ocean Modeling System (ROMS). Simulated waves are generated on the lake with Simulating WAves Nearshore (SWAN). Wind setdown provides the opportunity to eliminate wave setup as a contributing factor, since waves are minimal at the upwind shore. The study finds that model results significantly underestimate wind setdown and storm surge when a typical open-ocean formulation without waves is used for the drag coefficient. The contribution of waves to wind setdown and storm surge is 34.7%. Scattered lake ice also increases the effective drag coefficient by a factor of 1.1. PMID:23977309

Analysis of Storm Surge in Hong Kong

NASA Astrophysics Data System (ADS)

Kao, W. H.

2017-12-01

A storm surge is a type of coastal flood that is caused by low-pressure systems such as tropical cyclones. Storm surges caused by tropical cyclones can be very powerful and damaging, as they can flood coastal areas, and even destroy infrastructure in serious cases. Some serious cases of storm surges leading to more than thousands of deaths include Hurricane Katrina (2005) in New Orleans and Typhoon Haiyan (2013) in Philippines. Hong Kong is a coastal city that is prone to tropical cyclones, having an average of 5-6 tropical cyclones entering 500km range of Hong Kong per year. Storm surges have seriously damaged Hong Kong in the past, causing more than 100 deaths by Typhoon Wanda (1962), and leading to serious damage to Tai O and Cheung Chau by Typhoon Hagupit (2008). To prevent economic damage and casualties from storm surges, accurately predicting the height of storm surges and giving timely warnings to citizens is very important. In this project, I will be analyzing how different factors affect the height of storm surge, mainly using data from Hong Kong. These factors include the windspeed in Hong Kong, the atmospheric pressure in Hong Kong, the moon phase, the wind direction, the intensity of the tropical cyclone, distance between the tropical cyclone and Hong Kong, the direction of the tropical cyclone relative to Hong Kong, the speed of movement of the tropical cyclone and more. My findings will also be compared with cases from other places, to see if my findings also apply for other places.

Impact of hydrogeological factors on groundwater salinization due to ocean-surge inundation

NASA Astrophysics Data System (ADS)

Yang, Jie; Zhang, Huichen; Yu, Xuan; Graf, Thomas; Michael, Holly A.

2018-01-01

Ocean surges cause seawater inundation of coastal inland areas. Subsequently, seawater infiltrates into coastal aquifers and threatens the fresh groundwater resource. The severity of resulting salinization can be affected by hydrogeological factors including aquifer properties and hydrologic conditions, however, little research has been done to assess these effects. To understand the impacts of hydrogeological factors on groundwater salinization, we numerically simulated an ocean-surge inundation event on a two-dimensional conceptual coastal aquifer using a coupled surface-subsurface approach. We varied model permeability (including anisotropy), inland hydraulic gradient, and recharge rate. Three salinization-assessment indicators were developed, based on flushing time, depth of salt penetration, and a combination of the two, weighted flushing time, with which the impact of hydrogeological factors on groundwater vulnerability to salinization were quantitatively assessed. The vulnerability of coastal aquifers increases with increasing isotropic permeability. Low horizontal permeability (kx) and high vertical permeability (kz) lead to high aquifer vulnerability, and high kx and low kz lead to low aquifer vulnerability. Vulnerability decreases with increasing groundwater hydraulic gradient and increasing recharge rate. Additionally, coastal aquifers with a low recharge rate (R ≤ 300 mm yr-1) may be highly vulnerable to ocean-surge inundation. This study shows how the newly introduced indicators can be used to quantitatively assess coastal aquifer vulnerability. The results are important for global vulnerability assessment of coastal aquifers to ocean-surge inundation.

Coastal emergency managers' preferences for storm surge forecast communication.

PubMed

Morrow, Betty Hearn; Lazo, Jeffrey K

2014-01-01

Storm surge, the most deadly hazard associated with tropical and extratropical cyclones, is the basis for most evacuation decisions by authorities. One factor believed to be associated with evacuation noncompliance is a lack of understanding of storm surge. To address this problem, federal agencies responsible for cyclone forecasts are seeking more effective ways of communicating storm surge threat. To inform this process, they are engaging various partners in the forecast and warning process.This project focuses on emergency managers. Fifty-three emergency managers (EMs) from the Gulf and lower Atlantic coasts were surveyed to elicit their experience with, sources of, and preferences for storm surge information. The emergency managers-who are well seasoned in hurricane response and generally rate the surge risk in their coastal areas above average or extremely high-listed storm surge as their major concern with respect to hurricanes. They reported a general lack of public awareness about surge. Overall they support new ways to convey the potential danger to the public, including the issuance of separate storm surge watches and warnings, and the expression of surge heights using feet above ground level. These EMs would like more maps, graphics, and visual materials for use in communicating with the public. An important concern is the timing of surge forecasts-whether they receive them early enough to be useful in their evacuation decisions.

Epiregulin-dependent amphiregulin expression and ERBB2 signaling are involved in luteinizing hormone-induced paracrine signaling pathways in mouse ovary.

PubMed

Kim, Kyoungmi; Lee, Hyunji; Threadgill, David W; Lee, Daekee

2011-02-11

Sustained EGF receptor (EGFR) phosphorylation by de novo synthesis of EGFR ligands plays an essential role in mediating luteinizing hormone (LH)-induced ovulation process in the preovulatory follicles (POFs). In the present study, the effect of epiregulin (EREG) on oocyte maturation and ovulation was investigated using Ereg knockout (Ereg-/-) mice congenic on a C57BL/6 background. Rate of spontaneous oocyte meiotic resumption of denuded oocytes (DOs) or cumulus cell-oocyte complexes (COCs) in vitro is similar between wild-type and Ereg-/- mice. However, gonadotropin-induced meiotic resumption in vivo is attenuated, and the number of COCs with expanded cumulus matrix and superovulated eggs dramatically decrease in Ereg-/- mice. Nonetheless, the number of eggs ovulated during normal estrus cycles and litter sizes in Ereg-/- mice are comparable to those of wild-type littermates. In contrast to other EGFR ligands, induction of amphiregulin (Areg) mRNA is severely reduced in ovaries collected from Ereg-/- mice either after human chorionic gonadotropin (hCG) treatment in immature mice or LH surge in adults. Gonadotropin-induced EGFR and ERBB2 phosphorylation in ovaries is attenuated in immature Ereg-/- mice, and MAPK3/1 phosphorylation and prostaglandin synthase 2 (PTGS2) protein levels are reduced. This attenuation, however, is no longer detectable in adult Ereg-/- mice after LH surge. This study implicates that EREG mediates signals downstream of Areg mRNA expression and that EGFR-ERBB2 signals contributes to regulation of ovulation process. Copyright © 2011 Elsevier Inc. All rights reserved.

Evaluation of Loss Due to Storm Surge Disasters in China Based on Econometric Model Groups.

PubMed

Jin, Xue; Shi, Xiaoxia; Gao, Jintian; Xu, Tongbin; Yin, Kedong

2018-03-27

Storm surge has become an important factor restricting the economic and social development of China's coastal regions. In order to improve the scientific judgment of future storm surge damage, a method of model groups is proposed to refine the evaluation of the loss due to storm surges. Due to the relative dispersion and poor regularity of the natural property data (login center air pressure, maximum wind speed, maximum storm water, super warning water level, etc.), storm surge disaster is divided based on eight kinds of storm surge disaster grade division methods combined with storm surge water, hypervigilance tide level, and disaster loss. The storm surge disaster loss measurement model groups consist of eight equations, and six major modules are constructed: storm surge disaster in agricultural loss, fishery loss, human resource loss, engineering facility loss, living facility loss, and direct economic loss. Finally, the support vector machine (SVM) model is used to evaluate the loss and the intra-sample prediction. It is indicated that the equations of the model groups can reflect in detail the relationship between the damage of storm surges and other related variables. Based on a comparison of the original value and the predicted value error, the model groups pass the test, providing scientific support and a decision basis for the early layout of disaster prevention and mitigation.

Evaluation of Loss Due to Storm Surge Disasters in China Based on Econometric Model Groups

PubMed Central

Shi, Xiaoxia; Xu, Tongbin; Yin, Kedong

2018-01-01

Storm surge has become an important factor restricting the economic and social development of China’s coastal regions. In order to improve the scientific judgment of future storm surge damage, a method of model groups is proposed to refine the evaluation of the loss due to storm surges. Due to the relative dispersion and poor regularity of the natural property data (login center air pressure, maximum wind speed, maximum storm water, super warning water level, etc.), storm surge disaster is divided based on eight kinds of storm surge disaster grade division methods combined with storm surge water, hypervigilance tide level, and disaster loss. The storm surge disaster loss measurement model groups consist of eight equations, and six major modules are constructed: storm surge disaster in agricultural loss, fishery loss, human resource loss, engineering facility loss, living facility loss, and direct economic loss. Finally, the support vector machine (SVM) model is used to evaluate the loss and the intra-sample prediction. It is indicated that the equations of the model groups can reflect in detail the relationship between the damage of storm surges and other related variables. Based on a comparison of the original value and the predicted value error, the model groups pass the test, providing scientific support and a decision basis for the early layout of disaster prevention and mitigation. PMID:29584628

Storm surge along the Pacific coast of North America

NASA Astrophysics Data System (ADS)

Bromirski, Peter D.; Flick, Reinhard E.; Miller, Arthur J.

2017-01-01

Storm surge is an important factor that contributes to coastal flooding and erosion. Storm surge magnitude along eastern North Pacific coasts results primarily from low sea level pressure (SLP). Thus, coastal regions where high surge occurs identify the dominant locations where intense storms make landfall, controlled by storm track across the North Pacific. Here storm surge variability along the Pacific coast of North America is characterized by positive nontide residuals at a network of tide gauge stations from southern California to Alaska. The magnitudes of mean and extreme storm surge generally increase from south to north, with typically high amplitude surge north of Cape Mendocino and lower surge to the south. Correlation of mode 1 nontide principal component (PC1) during winter months (December-February) with anomalous SLP over the northeast Pacific indicates that the dominant storm landfall region is along the Cascadia/British Columbia coast. Although empirical orthogonal function spatial patterns show substantial interannual variability, similar correlation patterns of nontide PC1 over the 1948-1975 and 1983-2014 epochs with anomalous SLP suggest that, when considering decadal-scale time periods, storm surge and associated tracks have generally not changed appreciably since 1948. Nontide PC1 is well correlated with PC1 of both anomalous SLP and modeled wave height near the tide gauge stations, reflecting the interrelationship between storms, surge, and waves. Weaker surge south of Cape Mendocino during the 2015-2016 El Niño compared with 1982-1983 may result from changes in Hadley circulation. Importantly from a coastal impacts perspective, extreme storm surge events are often accompanied by high waves.

Response of surge protection devices to fast rising pulses

NASA Technical Reports Server (NTRS)

Mindel, I. N.

1980-01-01

Two types of lightning protection modules incorporating leadless (pill type) Zener like devices were evaluated with regard to their ability to suppress EMP induced transients. Two series of tests were performed to evaluate the ability of these modules to react to fast rate of rise ( 1Kv/ns) transients, and the attenuation introduced and the ability to limit damped sinusoid pulses which may be induced due to an EMP resulting from a nuclear detonation.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cazanave, Sophie; Vadrot, Nathalie; Tinel, Marina

Fas stimulation recruits neutrophils and activates macrophages that secrete tumor necrosis factor-{alpha} (TNF-{alpha}), which aggravates Fas-mediated liver injury. To determine whether nonsteroidal anti-inflammatory drugs modify these processes, we challenged 24-hour-fasted mice with the agonistic Jo2 anti-Fas antibody (4 {mu}g/mouse), and treated the animals 1 h later with saline or ibuprofen (250 mg/kg), a dual cyclooxygenase (COX)-1 and COX-2 inhibitor. Ibuprofen attenuated the Jo2-mediated recruitment/activation of myeloperoxidase-secreting neutrophils/macrophages in the liver, and attenuated the surge in serum TNF-{alpha}. Ibuprofen also minimized hepatic glutathione depletion, Bid truncation, caspase activation, outer mitochondrial membrane rupture, hepatocyte apoptosis and the increase in serum alanine aminotransferasemore » (ALT) activity 5 h after Jo2 administration, to finally decrease mouse mortality at later times. The concomitant administration of pentoxifylline (decreasing TNF-{alpha} secretion) and infliximab (trapping TNF-{alpha}) likewise attenuated the Jo2-mediated increase in TNF-{alpha}, the decrease in hepatic glutathione, and the increase in serum ALT activity 5 h after Jo2 administration. The concomitant administration of the COX-1 inhibitor, SC-560 (10 mg/kg) and the COX-2 inhibitor, celecoxib (40 mg/kg) 1 h after Jo2 administration, also decreased liver injury 5 h after Jo2 administration. In contrast, SC-560 (10 mg/kg) or celecoxib (40 or 160 mg/kg) given alone had no significant protective effects. In conclusion, secondary TNF-{alpha} secretion plays an important role in Jo2-mediated glutathione depletion and liver injury. The combined inhibition of COX-1 and COX-2 by ibuprofen attenuates TNF-{alpha} secretion, glutathione depletion, mitochondrial alterations, hepatic apoptosis and mortality in Jo2-treated fasted mice.« less

Segregation of asphalt mixes caused by surge silos : final report.

DOT National Transportation Integrated Search

1982-01-01

Segregation of asphalt mixes continues to be a problem in Virginia, particularly with base mixes and coarse surface mixes. Although the problem is encountered primarily on jobs using surge silos, it has been related to other factors such as mix desig...

Pyruvate Dehydrogenase Kinase-mediated Glycolytic Metabolic Shift in the Dorsal Root Ganglion Drives Painful Diabetic Neuropathy*

PubMed Central

Rahman, Md Habibur; Jha, Mithilesh Kumar; Kim, Jong-Heon; Nam, Youngpyo; Lee, Maan Gee; Go, Younghoon; Harris, Robert A.; Park, Dong Ho; Kook, Hyun; Lee, In-Kyu; Suk, Kyoungho

2016-01-01

The dorsal root ganglion (DRG) is a highly vulnerable site in diabetic neuropathy. Under diabetic conditions, the DRG is subjected to tissue ischemia or lower ambient oxygen tension that leads to aberrant metabolic functions. Metabolic dysfunctions have been documented to play a crucial role in the pathogenesis of diverse pain hypersensitivities. However, the contribution of diabetes-induced metabolic dysfunctions in the DRG to the pathogenesis of painful diabetic neuropathy remains ill-explored. In this study, we report that pyruvate dehydrogenase kinases (PDK2 and PDK4), key regulatory enzymes in glucose metabolism, mediate glycolytic metabolic shift in the DRG leading to painful diabetic neuropathy. Streptozotocin-induced diabetes substantially enhanced the expression and activity of the PDKs in the DRG, and the genetic ablation of Pdk2 and Pdk4 attenuated the hyperglycemia-induced pain hypersensitivity. Mechanistically, Pdk2/4 deficiency inhibited the diabetes-induced lactate surge, expression of pain-related ion channels, activation of satellite glial cells, and infiltration of macrophages in the DRG, in addition to reducing central sensitization and neuroinflammation hallmarks in the spinal cord, which probably accounts for the attenuated pain hypersensitivity. Pdk2/4-deficient mice were partly resistant to the diabetes-induced loss of peripheral nerve structure and function. Furthermore, in the experiments using DRG neuron cultures, lactic acid treatment enhanced the expression of the ion channels and compromised cell viability. Finally, the pharmacological inhibition of DRG PDKs or lactic acid production substantially attenuated diabetes-induced pain hypersensitivity. Taken together, PDK2/4 induction and the subsequent lactate surge induce the metabolic shift in the diabetic DRG, thereby contributing to the pathogenesis of painful diabetic neuropathy. PMID:26769971

Surge Pressure Mitigation in the Global Precipitation Measurement Mission Core Propulsion System

NASA Technical Reports Server (NTRS)

Scroggins, Ashley R.; Fiebig, Mark D.

2014-01-01

The Global Precipitation Measurement (GPM) mission is an international partnership between NASA and JAXA whose Core spacecraft performs cutting-edge measurements of rainfall and snowfall worldwide and unifies data gathered by a network of precipitation measurement satellites. The Core spacecraft's propulsion system is a blowdown monopropellant system with an initial hydrazine load of 545 kg in a single composite overwrapped propellant tank. At launch, the propulsion system contained propellant in the tank and manifold tubes upstream of the latch valves, with low-pressure helium gas in the manifold tubes downstream of the latch valves. The system had a relatively high beginning-of- life pressure and long downstream manifold lines; these factors created conditions that were conducive to high surge pressures. This paper discusses the GPM project's approach to surge mitigation in the propulsion system design. The paper describes the surge testing program and results, with discussions of specific difficulties encountered. Based on the results of surge testing and pressure drop analyses, a unique configuration of cavitating venturis was chosen to mitigate surge while minimizing pressure losses during thruster maneuvers. This paper concludes with a discussion of overall lessons learned with surge pressure testing for NASA Goddard spacecraft programs.

The analysis of dependence between extreme rainfall and storm surge in the coastal zone

NASA Astrophysics Data System (ADS)

Zheng, F.; Westra, S.

2012-12-01

Flooding in coastal catchments can be caused by runoff generated by an extreme rainfall event, elevated sea levels due to an extreme storm surge event, or the combination of both processes occurring simultaneously or in close succession. Dependence in extreme rainfall and storm surge arises because common meteorological forcings often drive both variables; for example, cyclonic systems may produce extreme rainfall, strong onshore winds and an inverse barometric effect simultaneously, which the former factor influencing catchment discharge and the latter two factors influencing storm surge. Nevertheless there is also the possibility that only one of the variables is extreme at any given time, so that the dependence between rainfall and storm surge is not perfect. Quantification of the strength of dependence between these processes is critical in evaluating the magnitude of flood risk in the coastal zone. This may become more important in the future as the majority of the coastal areas are threatened by the sea level rise due to the climate change. This research uses the most comprehensive record of rainfall and storm surge along the coastline of Australia collected to-date to investigate the strength of dependence between the extreme rainfall and storm surge along the Australia coastline. A bivariate logistic threshold-excess model was employed to this end to carry out the dependence analysis. The strength of the estimated dependence is then evaluated as a function of several factors including: the distance between the tidal gauge and the rain gauge; the lag between the extreme precipitation event and extreme surge event; and the duration of the maximum storm burst. The results show that the dependence between the extreme rainfall and storm surge along the Australia coastline is statistically significant, although some locations clearly exhibit stronger dependence than others. We hypothesize that this is due to a combination of large-scale meteorological effects as well as local scale bathymetry. Additionally, significant dependence can be observed over spatial distances of up to several hundred kilometers, implying that meso-scale meteorological forcings may play an important role in driving the dependence. This is also consistent with the result which shows that significant dependence often remaining for lags of up to one or two days between extremal rainfall and storm surge events. The influence of storm burst duration can also be observed, with rainfall extremes lasting more than several hours typically being more closely associated with storm surge compared with sub-hourly rainfall extremes. These results will have profound implications for how flood risk is evaluated along the coastal zone in Australia, with the strength of dependence varying depending on: (1) the dominant meteorological conditions; (2) the local estuary configuration, influencing the strength of the surge; and (3) the catchment attributes, influencing the duration of the storm burst that will deliver the peak flood events. Although a strong random component remains, we show that the probability of an extreme storm surge during an extreme rainfall event (or vice versa) can be up to ten times greater than under the situation under which there is no dependence, suggesting that failure to account for these interactions can result in a substantial underestimation of flood risk.

Introduction on the operational storm surge forecasting system in Korea Operational Oceanographic System (KOOS)

NASA Astrophysics Data System (ADS)

Kwon, Jae-Il; Park, Kwang-Soon; Choi, Jung-Woon; Lee, Jong-Chan; Heo, Ki-Young; Kim, Sang-Ik

2017-04-01

During last more than 50 years, 258 typhoons passed and affected the Korean peninsula in terms of high winds, storm surges and extreme waves. In this study we explored the performance of the operational storm surge forecasting system in the Korea Operational Oceanographic System (KOOS) with 8 typhoons from 2010 to 2016. The operation storm surge forecasting system for the typhoon in KOOS is based on 2D depth averaged model with tides and CE (U.S. Army Corps of Engineers) wind model. Two key parameters of CE wind model, the locations of typhoon center and its central atmospheric pressure are based from Korea Meteorological administrative (KMA)'s typhoon information provided from 1 day to 3 hour intervals with the approach of typhoon through the KMA's web-site. For 8 typhoons cases, the overall errors, other performances and analysis such as peak time and surge duration are presented in each case. The most important factor in the storm surge errors in the operational forecasting system is the accuracy of typhoon passage prediction.

Seismic Monitoring of Ice Generated Events at the Bering Glacier

NASA Astrophysics Data System (ADS)

Fitzgerald, K.; Richardson, J.; Pennington, W.

2008-12-01

The Bering Glacier, located in southeast Alaska, is the largest glacier in North America with a surface area of approximately 5,175 square kilometers. It extends from its source in the Bagley Icefield to its terminus in tidal Vitus Lake, which drains into the Gulf of Alaska. It is known that the glacier progresses downhill through the mechanisms of plastic crystal deformation and basal sliding. However, the basal processes which take place tens to hundreds of meters below the surface are not well understood, except through the study of sub- glacial landforms and passive seismology. Additionally, the sub-glacial processes enabling the surges, which occur approximately every two decades, are poorly understood. Two summer field campaigns in 2007 and 2008 were designed to investigate this process near the terminus of the glacier. During the summer of 2007, a field experiment at the Bering Glacier was conducted using a sparse array of L-22 short period sensors to monitor ice-related events. The array was in place for slightly over a week in August and consisted of five stations centered about the final turn of the glacier west of the Grindle Hills. Many events were observed, but due to the large distance between stations and the highly attenuating surface ice, few events were large enough to be recorded on sufficient stations to be accurately located and described. During August 2008, six stations were deployed for a similar length of time, but with a closer spacing. With this improved array, events were located and described more accurately, leading to additional conclusions about the surface, interior, and sub-glacial ice processes producing seismic signals. While the glacier was not surging during the experiment, this study may provide information on the non-surging, sub-glacial base level activity. It is generally expected that another surge will take place within a few years, and baseline studies such as this may assist in understanding the nature of surges.

Long-term clinical impact of PSA surge in castration-resistant prostate cancer patients treated with abiraterone.

PubMed

Conteduca, Vincenza; Caffo, Orazio; Lolli, Cristian; Aieta, Michele; Scarpi, Emanuela; Bianchi, Emanuela; Maines, Francesca; Schepisi, Giuseppe; Salvi, Samanta; Massari, Francesco; Carrozza, Francesco; Veccia, Antonello; Chiuri, Vincenzo E; Campadelli, Enrico; Facchini, Gaetano; De Giorgi, Ugo

2017-06-01

Early changes in PSA have been evaluated in association to treatment outcome. The aim of this study was to assess PSA surge phenomenon in castration-resistant prostate cancer (CRPC) patients treated with abiraterone and to correlate those variations with long-term treatment outcome. We retrospectively evaluated 330 CRPC patients in 11 Italian hospitals, monitoring PSA levels at baseline and every 4 weeks. Other clinical, biochemical and molecular parameters were determined at baseline. We considered PSA surge as PSA increase within the first 8 weeks from starting abiraterone more than 1% from baseline followed by a PSA decline. The log-rank test was applied to compare survival between groups of patients according to PSA surge. The impact of PSA surge on survival was evaluated by Cox regression analyses. A total of 330 patients with CRPC, median age 74 years (range, 45-90), received abiraterone (281 chemotherapy-treated and 49 chemotherapy-naïve). PSA surge was observed in 20 (7%) post-chemotherapy and 2 (4%) chemotherapy-naïve patients. For overall patients presenting PSA surge, timing of PSA peak from baseline was 5 ± 1.8 weeks and PSA rise from baseline was 21 ± 18.4%. The overall median follow-up was 23 months (range 1-62). No significant differences in progression-free survival and overall survival were observed between patients with and without PSA surge (P = 0.16 and =0.86, respectively). In addition, uni- and multivariate analyses showed no baseline factors related to PSA surge. PSA surge occurs in both chemotherapy-treated and chemotherapy-naïve patients treated with abiraterone resulting, however, in no long-term impact on outcome. Physicians and patients should be aware of PSA surge challenge to prevent a premature discontinuation of potentially effective therapy with abiraterone. Further larger and prospective studies are warranted to investigate this not infrequent phenomenon. © 2017 Wiley Periodicals, Inc.

Study of surge current effects on solid tantalum capacitors

NASA Technical Reports Server (NTRS)

1980-01-01

Results are presented of a 2,000 hour cycled life test program conducted to determine the effect of short term surge current screening on approximately 47 micron f/volt solid tantalum capacitors. The format provides average values and standard deviations of the parameters, capacitance, dissipation factor, and equivalent series resistance at 120 Hz, 1KHz, abd 40 KHz.

A numerical study on hurricane-induced storm surge and inundation in Charleston Harbor, South Carolina

NASA Astrophysics Data System (ADS)

Peng, Machuan; Xie, Lian; Pietrafesa, Leonard J.

2006-08-01

A storm surge and inundation model is configured in Charleston Harbor and its adjacent coastal region to study the harbor's response to hurricanes. The hydrodynamic component of the modeling system is based on the Princeton Ocean Model, and a scheme with multiple inundation speed options is imbedded in the model for the inundation calculation. Historic observations (Hurricane Hugo and its related storm surge and inundation) in the Charleston Harbor region indicate that among three possible inundation speeds in the model, taking Ct (gd)1/2 (Ct is a terrain-related parameter) as the inundation speed is the best choice. Choosing a different inundation speed in the model has effects not only on inundation area but also on storm surge height. A nesting technique is necessary for the model system to capture the mesoscale feature of a hurricane and meanwhile to maintain a higher horizontal resolution in the harbor region, where details of the storm surge and inundation are required. Hurricane-induced storm surge and inundation are very sensitive to storm tracks. Twelve hurricanes with different tracks are simulated to investigate how Charleston Harbor might respond to tracks that are parallel or perpendicular to the coastline or landfall at Charleston at different angles. Experiments show that large differences of storm surge and inundation may have occurred if Hurricane Hugo had approached Charleston Harbor with a slightly different angle. A hurricane's central pressure, radius of maximum wind, and translation speed have their own complicated effects on surge and inundation when the hurricane approaches the coast on different tracks. Systematic experiments are performed in order to illustrate how each of such factors, or a combination of them, may affect the storm surge height and inundation area in the Charleston Harbor region. Finally, suggestions are given on how this numerical model system may be used for hurricane-induced storm surge and inundation forecasting.

Multi-factor evaluation indicator method for the risk assessment of atmospheric and oceanic hazard group due to the attack of tropical cyclones

NASA Astrophysics Data System (ADS)

Qi, Peng; Du, Mei

2018-06-01

China's southeast coastal areas frequently suffer from storm surge due to the attack of tropical cyclones (TCs) every year. Hazards induced by TCs are complex, such as strong wind, huge waves, storm surge, heavy rain, floods, and so on. The atmospheric and oceanic hazards cause serious disasters and substantial economic losses. This paper, from the perspective of hazard group, sets up a multi-factor evaluation method for the risk assessment of TC hazards using historical extreme data of concerned atmospheric and oceanic elements. Based on the natural hazard dynamic process, the multi-factor indicator system is composed of nine natural hazard factors representing intensity and frequency, respectively. Contributing to the indicator system, in order of importance, are maximum wind speed by TCs, attack frequency of TCs, maximum surge height, maximum wave height, frequency of gusts ≥ Scale 8, rainstorm intensity, maximum tidal range, rainstorm frequency, then sea-level rising rate. The first four factors are the most important, whose weights exceed 10% in the indicator system. With normalization processing, all the single-hazard factors are superposed by multiplying their weights to generate a superposed TC hazard. The multi-factor evaluation indicator method was applied to the risk assessment of typhoon-induced atmospheric and oceanic hazard group in typhoon-prone southeast coastal cities of China.

Factors associated with preparedness of the US healthcare system to respond to a pediatric surge during an infectious disease pandemic: Is our nation prepared?

PubMed

Anthony, Christy; Thomas, Tito Joe; Berg, Bridget M; Burke, Rita V; Upperman, Jeffrey S

2017-01-01

Recent incidents have demonstrated that the US health system is unprepared for infectious pandemics resulting in a pediatric surge. Development of efficient plans and a structured and coordinated regional response to pediatric pandemic surge remains an opportunity. To address this gap, we conducted a literature review to assess current efforts, propose a response plan structure, and recommend policy actions. A literature review, utilizing MEDLINE and PubMed, through March 2017 identified articles regarding infectious disease pandemics affecting the US pediatric population. After review of current literature, a proposed response plan structure for a pediatric pandemic surge was designed. Inclusion and exclusion criteria reduced an initial screening of 1,787 articles to 162 articles. Articles ranged in their discussion of pediatric pandemic surge. Review of the articles led to the proposal of organizing the results according to 4 S's; (1) Structure, (2) Staff, (3) Stuff (Resources), and (4) Space. The review has supported the concern that the US health system is unprepared for a pediatric surge induced by infectious disease pandemics. Common themes suggest that response plans should reflect the 4Ss and national guidelines must be translated into regional response systems that account for local nuances.

Top income shares in Canada: recent trends and policy implications

PubMed Central

Veall, Michael R

2012-01-01

According to Canadian taxfiler data, over the last thirty years there has been a surge in the income shares of the top 1%, top 0.1% and top 0.01% of income recipients, even with longitudinal smoothing by individual using three- or five-year moving averages. Top shares fell in 2008 and 2009, but only by a fraction of the overall surge. Alberta, British Columbia, and Ontario have much more pronounced surges than other provinces. Part of the Canadian surge is likely attributable to U.S. factors, but a comprehensive explanation remains elusive. Even so, I draw implications for policies that might achieve some support from across the political spectrum, including the elimination of tax preferences that favour those with high incomes, the promotion of shareholder democracy and, to maintain Canada's relatively high intergenerational mobility, continued wide accessibility to healthcare and education. PMID:23335814

Factor analysis of safety for visitors to a mega-event.

PubMed

Kwon, Young Guk; Park, Hyun Jee

2002-01-01

This paper investigated the safety factors considered by visitors to the Kwangju Biennale 2000 and analyzed the correlation between the safety factors and the demographic characteristics of the visitors. Global tourism increased throughout the 1990s, with the biggest surge occurring in the Asia-Pacific region. Long-distance travel is also increasing, and at a rate faster than the global average. The opportunities for event tourism appear to be strong almost everywhere, even though recessions may have an impact on these destinations. Along with this upward trend, competition for more desirable tourists is also surging (Getz, 1997). Therefore event tourism is appearing as a powerful method in the fierce competition around the tourism industry.

Population vulnerability to storm surge flooding in coastal Virginia, USA.

PubMed

Liu, Hua; Behr, Joshua G; Diaz, Rafael

2016-07-01

This study aims to assess the vulnerability of populations to storm surge flooding in 12 coastal localities of Virginia, USA. Population vulnerability is assessed by way of 3 physical factors (elevation, slope, and storm surge category), 3 built-up components (road availability, access to hospitals, and access to shelters), and 3 household conditions (storm preparedness, financial constraints to recovering from severe weather events, and health fragility). Fuzzy analysis is used to generate maps illustrating variation in several types of population vulnerability across the region. When considering physical factors and household conditions, the most vulnerable neighborhoods to sea level rise and storm surge flooding are largely found in urban areas. However, when considering access to critical infrastructure, we find rural residents to be more vulnerable than nonrural residents. These detailed assessments can inform both local and state governments in catastrophic planning. In addition, the methodology may be generalized to assess vulnerability in other coastal corridors and communities. The originality is highlighted by evaluating socioeconomic conditions at refined scale, incorporating a broader range of human perceptions and predispositions, and employing a geoinformatics approach combining physical, built-up, and socioeconomic conditions for population vulnerability assessment. Integr Environ Assess Manag 2016;12:500-509. © 2015 SETAC. © 2015 SETAC.

Impact of outdoor temperature on prewaking morning surge and nocturnal decline in blood pressure in a Japanese population.

PubMed

Murakami, Shougo; Otsuka, Kuniaki; Kono, Tatsuji; Soyama, Akiko; Umeda, Tatsuya; Yamamoto, Naomune; Morita, Hideaki; Yamanaka, Gaku; Kitaura, Yasushi

2011-01-01

Seasonal variations in blood pressure (BP) have often been attributed to meteorological factors, especially changes in outdoor temperature. We evaluated the direct association between meteorological factors and circadian BP variability. Twenty-four-hour ambulatory BP was monitored continuously for 7 days in 158 subjects. Mean awake, asleep, morning (first 2 h after waking) BP, prewaking morning BP surge (morning systolic BP (SBP)-mean SBP during the 2-h period before waking) and nocturnal BP decline were measured each day. We compared BP values for the lowest and highest days with regard to the daily mean outdoor temperature and mean atmospheric pressure. Morning BP and prewaking morning BP surge on the coldest day were significantly higher than those on the warmest day (morning SBP, 136.6 ± 1.6 vs. 133.1 ± 1.5 mm Hg, P = 0.002; morning diastolic BP, 84.4 ± 0.9 vs. 82.6 ± 0.9 mm Hg, P = 0.02; and prewaking morning BP surge, 20.8 ± 1.3 vs. 15.3 ± 1.3 mm Hg, P = 0.0004). The magnitude of nocturnal BP decline on the coldest day was significantly greater than that on the warmest day (15.8 ± 0.7 vs. 13.9 ± 0.7%, P = 0.01). Outdoor temperature is an important determinant of morning BP, prewaking morning BP surge and the magnitude of nocturnal BP decline. These findings may have important implications in management of hypertension and prevention of cardiovascular events.

A numerical study of vegetation impact on reducing storm surge by wetlands in a semi-enclosed estuary

USGS Publications Warehouse

Kelin, Hu; Qin, Chen; Wang, Hongqing

2014-01-01

Coastal wetlands play a unique role in extreme hurricane events. The impact of wetlands on storm surge depends on multiple factors including vegetation, landscape, and storm characteristics. The Delft3D model, in which vegetation effects on flow and turbulence are explicitly incorporated, was applied to the semi-enclosed Breton Sound (BS) estuary in coastal Louisiana to investigate the wetland impact. Guided by extensive field observations, a series of numerical experiments were conducted based on variations of actual vegetation properties and storm parameters from Hurricane Isaac in 2012. Both the vegetation-induced maximum surge reduction (MSR) and maximum surge reduction rate (MSRR) increased with stem height and stem density, and were more sensitive to stem height. The MSR and MSRR decreased significantly with increasing wind intensity. The MSRR was the highest with a fast-moving weak storm. It was also found that the MSRR varied proportionally to the expression involving the maximum bulk velocity and surge over the area of interest, and was more dependent on the maximum bulk surge. Both MSR and MSRR appeared to increase when the area of interest decreased from the whole BS estuary to the upper estuary. Within the range of the numerical experiments, the maximum simulated MSR and MSRR over the upper estuary were 0.7 m and 37%, respectively.

Long-lived weight-reduced αMUPA mice show higher and longer maternal-dependent postnatal leptin surge

PubMed Central

Pinsky, Mariel; Rauch, Maayan; Abbas, Atallah; Sharabi-Nov, Adi; Tamir, Snait

2017-01-01

We investigated whether long-lived weight-reduced αMUPA mice differ from their wild types in postnatal body composition and leptin level, and whether these differences are affected by maternal-borne factors. Newborn αMUPA and wild type mice had similar body weight and composition up to the third postnatal week, after which αMUPA mice maintained lower body weight due to lower fat-free mass. Both strains showed a surge in leptin levels at the second postnatal week, initiating earlier in αMUPA mice, rising higher and lasting longer than in the wild types, mainly in females. Leptin level in dams’ serum and breast milk, and in their pup’s stomach content were also higher in αMUPA than in the WT during the surge peak. Leptin surge preceded the strain divergence in body weight, and was associated with an age-dependent decrease in the leptin:fat mass ratio—suggesting that postnatal sex and strain differences in leptin ontogeny are strongly influenced by processes independent of fat mass, such as production and secretion, and possibly outside fat tissues. Dam removal elevated corticosterone level in female pups from both strains similarly, yet mitigated the leptin surge only in αMUPA–eliminating the strain differences in leptin levels. Overall, our results indicate that αMUPA’s postnatal leptin surge is more pronounced than in the wild type, more sensitive to maternal deprivation, less related to pup’s total adiposity, and is associated with a lower post-weaning fat-free mass. These strain-related postnatal differences may be related to αMUPA’s higher milk-borne leptin levels. Thus, our results support the use of αMUPA mice in future studies aimed to explore the relationship between maternal (i.e. milk-borne) factors, postnatal leptin levels, and post-weaning body composition and energy homeostasis. PMID:29190757

Tide-surge Interaction Intensified by the Taiwan Strait

NASA Astrophysics Data System (ADS)

Zhang, Wen-Zhou; Shi, Fengyan; Hong, Hua-Sheng; Shang, Shao-Ping; Kirby, James T.

2010-06-01

The Taiwan Strait is a long and wide shelf-channel where the hydrodynamics is extremely complex, being characterized by strong tides, and where storm surges frequently occur during the typhoon season. Obvious oscillations due to tide-surge interaction were observed by tide gauges along the northern Fujian coast, the west bank of the Taiwan Strait, during Typhoon Dan (1999). Numerical experiments indicate that nonlinear bottom friction (described by the quadratic formula) is a major factor to predict these oscillations while the nonlinear advective terms and the shallow water effect have little contribution. It is found that the tide-surge interaction in the northern portion of the Taiwan Strait is intensified by the strait. Simulations based on simplified topographies with and without the island of Taiwan show that, in the presence of the island, the channel effect strengthens tidal currents and tends to align the major axes of tidal ellipses along the channel direction. Storm-induced currents are also strengthened by the channel. The pattern of strong tidal currents and storm-induced currents along the channel direction enhances tide-surge interaction via the nonlinear bottom friction, resulting in the obvious oscillations along the northern Fujian coast.

Day/Night Variability in Blood Pressure: Influence of Posture and Physical Activity

PubMed Central

2013-01-01

BACKGROUND Blood pressure (BP) is highest during the day and lowest at night. Absence of this rhythm is a predictor of cardiovascular morbidity and mortality. Contributions of changes in posture and physical activity to the 24-hour day/night rhythm in BP are not well understood. We hypothesized that postural changes and physical activity contribute substantially to the day/night rhythm in BP. METHODS Fourteen healthy, sedentary, nonobese, normotensive men (aged 19–50 years) each completed an ambulatory and a bed rest condition during which BP was measured every 30–60 minutes for 24 hours. When ambulatory, subjects followed their usual routines without restrictions to capture the “normal” condition. During bed rest, subjects were constantly confined to bed in a 6-degree head-down position; therefore posture was constant, and physical activity was minimized. Two subjects were excluded from analysis because of irregular sleep timing. RESULTS The systolic and diastolic BP reduction during the sleep period was similar in ambulatory (−11±2mmHg/−8±1mmHg) and bed rest conditions (−8±3mmHg/−4±2mmHg; P = 0.38/P = 0.12). The morning surge in diastolic BP was attenuated during bed rest (P = 0.001), and there was a statistical trend for the same effect in systolic BP (P = 0.06). CONCLUSIONS A substantial proportion of the 24-hour BP rhythm remained during bed rest, indicating that typical daily changes in posture and/or physical activity do not entirely explain 24-hour BP variation under normal ambulatory conditions. However, the morning BP increase was attenuated during bed rest, suggesting that the adoption of an upright posture and/or physical activity in the morning contributes to the morning BP surge. PMID:23535155

Surge capacity principles: care of the critically ill and injured during pandemics and disasters: CHEST consensus statement.

PubMed

Hick, John L; Einav, Sharon; Hanfling, Dan; Kissoon, Niranjan; Dichter, Jeffrey R; Devereaux, Asha V; Christian, Michael D

2014-10-01

This article provides consensus suggestions for expanding critical care surge capacity and extension of critical care service capabilities in disasters or pandemics. It focuses on the principles and frameworks for expansion of intensive care services in hospitals in the developed world. A companion article addresses surge logistics, those elements that provide the capability to deliver mass critical care in disaster events. The suggestions in this article are important for all who are involved in large-scale disasters or pandemics with injured or critically ill multiple patients, including front-line clinicians, hospital administrators, and public health or government officials. The Surge Capacity topic panel developed 23 key questions focused on the following domains: systems issues; equipment, supplies, and pharmaceuticals; staffing; and informatics. Literature searches were conducted to identify evidence on which to base key suggestions. Most reports were small scale, were observational, or used flawed modeling; hence, the level of evidence on which to base recommendations was poor and did not permit the development of evidence-based recommendations. Therefore, the panel developed expert opinion-based suggestions using a modified Delphi process. Suggestions from the previous task force were also included for validation by the expert panel. This article presents 10 suggestions pertaining to the principles that should guide surge capacity and capability planning for mass critical care, including the role of critical care in disaster planning; the surge continuum; targets of surge response; situational awareness and information sharing; mitigating the impact on critical care; planning for the care of special populations; and service deescalation/cessation (also considered as engineered failure). Future reports on critical care surge should emphasize population-based outcomes as well as logistical details. Planning should be based on the projected number of critically ill or injured patients resulting from specific scenarios. This should include a consideration of ICU patient care requirements over time and must factor in resource constraints that may limit the ability to provide care. Standard ICU management forms and patient data forms to assess ICU surge capacity impacts should be created and used in disaster events.

A new concept for glacial geological investigations of surges, based on High-Arctic examples (Svalbard)

NASA Astrophysics Data System (ADS)

Lønne, Ida

2016-01-01

Svalbard is a key area for the investigation of glacial surges, and almost two centuries worth of field observations exists from this region. Studies have shown that the course of a surge and the associated formation of landforms are strongly influenced by basinal factors, and that the broad range of variables involved can hamper interpretations and comparisons. Based on a review of surges in Svalbard, a new concept for glacial geological investigations has been developed that combines ice-flows, ice-front movements, and morphostratigraphy. The concept is comprised of the following four elements: 1) classification based on the configuration and characteristics of the receiving basin, 2) division of the surge cycle into six stages, 3) guidelines for morphological mapping, and 4) use of an allostratigraphic approach for interpreting ice-front movements. In this context, delineation of the active phase is critical, which include the history of terminus movements, and four main categories of receiving basins are recognized. These are (A) terrestrial basins with deformable substrates, (B) terrestrial basins with poorly deformable substrates, (C) shallow water basins, and (D) deep water basins. The ice-front movement history is reconstructed by coupling information from the proglacial moraines (syn-surge), the supraglacial moraines (post-surge), and the associated traces of meltwater to the surge stages (I-VI). This approach has revealed a critical relationship between the termination of the active phase and three morphological elements, namely, the maximum ice-front position, the maximum moraine extent and the youngest proglacial moraine, which are unique for each of the basins A-D. The concept is thus a novel and more precise approach for mapping the active phase and the active phase duration, as shown by the ∼12-year long surge of Fridtjovbreen, where stage I was 30 months (inception), stage II was 54 months (ice-front advance), stage III was 12 months (stillstand), and stage IV was 48 months (retreat during active flow). The glacier has been in quiescent phase (stages V/VI) since 2002.

Forecasting of Storm Surge Floods Using ADCIRC and Optimized DEMs

NASA Technical Reports Server (NTRS)

Valenti, Elizabeth; Fitzpatrick, Patrick

2005-01-01

Increasing the accuracy of storm surge flood forecasts is essential for improving preparedness for hurricanes and other severe storms and, in particular, for optimizing evacuation scenarios. An interactive database, developed by WorldWinds, Inc., contains atlases of storm surge flood levels for the Louisiana/Mississippi gulf coast region. These atlases were developed to improve forecasting of flooding along the coastline and estuaries and in adjacent inland areas. Storm surge heights depend on a complex interaction of several factors, including: storm size, central minimum pressure, forward speed of motion, bottom topography near the point of landfall, astronomical tides, and most importantly, maximum wind speed. The information in the atlases was generated in over 100 computational simulations, partly by use of a parallel-processing version of the ADvanced CIRCulation (ADCIRC) model. ADCIRC is a nonlinear computational model of hydrodynamics, developed by the U.S. Army Corps of Engineers and the US Navy, as a family of two- and three-dimensional finite element based codes. It affords a capability for simulating tidal circulation and storm surge propagation over very large computational domains, while simultaneously providing high-resolution output in areas of complex shoreline and bathymetry. The ADCIRC finite-element grid for this project covered the Gulf of Mexico and contiguous basins, extending into the deep Atlantic Ocean with progressively higher resolution approaching the study area. The advantage of using ADCIRC over other storm surge models, such as SLOSH, is that input conditions can include all or part of wind stress, tides, wave stress, and river discharge, which serve to make the model output more accurate.

Numerical modeling of storm surges in the coast of Mozambique: the cases of tropical cyclones Bonita (1996) and Lisette (1997)

NASA Astrophysics Data System (ADS)

Bié, Alberto José; de Camargo, Ricardo; Mavume, Alberto Francisco; Harari, Joseph

2017-11-01

The coast of Mozambique is often affected by storms, particularly tropical cyclones during summer or sometimes midlatitude systems in the southern part. Storm surges combined with high freshwater discharge can drive huge coastal floods, affecting both urban and rural areas. To improve the knowledge about the impact of storm surges in the coast of Mozambique, this study presents the first attempt to model this phenomenon through the implementation of the Princeton Ocean Model (POM) in the Southwestern Indian Ocean domain (SWIO; 2-32°S, 28-85°E) using a regular grid with 1/6° of spatial resolution and 36 sigma levels. The simulation was performed for the period 1979-2010, and the most interesting events of surges were related to tropical cyclones Bonita (1996) and Lisette (1997) that occurred in the Mozambique Channel. The results showed that the model represented well the amplitude and phase of principal lunar and solar tidal constituents, as well as it captured the spatial pattern and magnitudes of SST with slight positive bias in summer and negative bias in winter months. In terms of SSH, the model underestimated the presence of mesoscale eddies, mainly in the Mozambique Channel. Our results also showed that the atmospheric sea level pressure had a significant contribution to storm heights during the landfall of the tropical cyclones Bonita (1996) and Lisette (1997) in the coast of Mozambique contributing with about 20 and 16% of the total surge height for each case, respectively, surpassing the contribution of the tide-surge nonlinear interactions by a factor of 2.

Granulocyte-Colony Stimulating Factor Increases Cerebral Blood Flow via a NO Surge Mediated by Akt/eNOS Pathway to Reduce Ischemic Injury

PubMed Central

Kuo, Jon-Son; Wang, Jia-Yi

2015-01-01

Granulocyte-colony stimulating factor (G-CSF) protects brain from ischemic/reperfusion (I/R) injury, and inhibition of nitric oxide (NO) synthases partially reduces G-CSF protection. We thus further investigated the effects of G-CSF on ischemia-induced NO production and its consequence on regional cerebral blood flow (rCBF) and neurological deficit. Endothelin-1 (ET-1) microinfused above middle cerebral artery caused a rapid reduction of rCBF (ischemia) which lasted for 30 minutes and was followed by a gradual recovery of blood flow (reperfusion) within the striatal region. Regional NO concentration increased rapidly (NO surge) during ischemia and recovered soon to the baseline. G-CSF increased rCBF resulting in shorter ischemic duration and an earlier onset of reperfusion. The enhancement of the ischemia-induced NO by G-CSF accompanied by elevation of phospho-Akt and phospho-eNOS was noted, suggesting an activation of Akt/eNOS. I/R-induced infarct volume and neurological deficits were also reduced by G-CSF treatment. Inhibition of NO synthesis by L-NG-Nitroarginine Methyl Ester (L-NAME) significantly reduced the effects of G-CSF on rCBF, NO surge, infarct volume, and neurological deficits. We conclude that G-CSF increases rCBF through a NO surge mediated by Akt/eNOS, which partially contributes to the beneficial effect of G-CSF on brain I/R injury. PMID:26146654

Observations of Building Performance under Combined Wind and Surge Loading from Hurricane Harvey

NASA Astrophysics Data System (ADS)

Lombardo, F.; Roueche, D. B.; Krupar, R. J.; Smith, D. J.; Soto, M. G.

2017-12-01

Hurricane Harvey struck the Texas coastline on August 25, 2017, as a Category 4 hurricane - the first major hurricane to reach the US in twelve years. Wind gusts over 130 mph and storm surge as high as 12.5 ft caused widespread damage to buildings and critical infrastructure in coastal communities including Rockport, Fulton, Port Aransas and Aransas Pass. This study presents the methodology and preliminary observations of a coordinated response effort to document residential building performance under wind and storm surge loading. Over a twelve day survey period the study team assessed the performance of more than 1,000 individual, geo-located residential buildings. Assessments were logged via a smartphone application to facilitate rapid collection and collation of geotagged photographs, building attributes and structural details, and structural damage observations. Detailed assessments were also made of hazard intensity, specifically storm surge heights and both wind speed and direction indicators. Preliminary observations and findings will be presented, showing strong gradients in damage between inland and coastal regions of the affected areas that may be due in part to enhanced individual loading effects of wind and storm surge and potentially joint-hazard loading effects. Contributing factors to the many cases of disproportionate damage observed in close proximity will also be discussed. Ongoing efforts to relate building damage to near-surface hazard measurements (e.g., radar, anemometry) in close proximity will also be described.

Storm surges and coastal impacts at Mar del Plata, Argentina

NASA Astrophysics Data System (ADS)

Fiore, Mónica M. E.; D'Onofrio, Enrique E.; Pousa, Jorge L.; Schnack, Enrique J.; Bértola, Germán R.

2009-07-01

Positive storm surges (PSS) lasting for several days can raise the water level producing significant differences between the observed level and the astronomical tide. These storm events can be more severe if they coincide with a high tide or if they bracket several tidal cycles, particularly in the case of the highest astronomical tide. Besides, the abnormal sea-level elevation near the coast can cause the highest waves generated to attack the upper beach. This combination of factors can produce severe erosion, threatening sectors located along the coastline. These effects would be more serious if the storm surge height and duration increase as a result of a climatic change. The Mar del Plata (Argentina) coastline and adjacent areas are exposed to such effects. A statistical characterization of PSS based on their intensity, duration and frequency, including a surge event classification, was performed utilizing tide-gauge records over the period 1956-2005. A storm erosion potential index (SEPI) was calculated from observed levels based on hourly water level measurements. The index was related to beach profile responses to storm events. Also, a return period for extreme SEPI values was calculated. Results show an increase in the average number of positive storm surge events per decade. Considering all the events, the last decade (1996-2005) exhibits an average 7% increase compared to each one of the previous decades. A similar behavior was found for the decadal average of the heights of maximum annual positive storm surges. In this case the average height of the last two decades exceeds that of the previous decades by approximately 8 cm. The decadal average of maximum annual duration of these meteorological events shows an increase of 2 h in the last three decades. A possible explanation of the changes in frequency, height and duration of positive storm surges at Mar del Plata would seem to lie in the relative mean sea-level rise.

Online, Instructional Television and Traditional Delivery: Student Characteristics and Success Factors in Business Statistics

ERIC Educational Resources Information Center

Dotterweich, Douglas P.; Rochelle, Carolyn F.

2012-01-01

Distance education has surged in recent years while research on student characteristics and factors leading to successful outcomes has not kept pace. This study examined characteristics of regional university students in undergraduate Business Statistics and factors linked to their success based on three modes of delivery - Online, Instructional…

Comparison of the 2008-2011 and 1993-1995 Surges of Bering Glacier, Alaska

NASA Astrophysics Data System (ADS)

Molnia, B. F.; Angeli, K.

2011-12-01

The 1993-1995 surge of Bering Glacier, Earth's largest surging temperate glacier, was intensively studied. A new surge, which began prior to March 9, 2009, was still active in early August 2011. As was the 1993-1995 surge, the current surge is being studied using multiple remote sensing and ground-based methodologies. The wealth of observations available of both surges permit comparisons to be drawn about similarities and differences regarding processes, timing, intensities, and related topics. For more than a year prior to each surge, the intensity of calving and the rate of terminus retreat in Tashalich Arm increased dramatically, approaching 4 m/d in late 2010. This was abruptly followed by a significant terminus advance. In the current surge, maximum advance rates exceeded 19 m/d between March 18 and May 10, 2011. Through July 20, maximum terminus advance approached 3.2 km with velocities above 8 m/d. Similar rates applied in the earlier surge. Each surge has resulted in a rapid and significant advance of the central Bering Lobe's terminus into Vitus Lake. The terminus advance results from the transfer of a substantial volume of ice from the Bagley Ice Valley into the expanding piedmont lobe. In both surges, conspicuous evidence of tens of meters of glacier surface lowering is visible on the south wall of Juniper Island. In the 1993-1995 surge, terminus advance between October 17, 1993 and May 16, 1994 was nearly 7.8 km, an average advance rate of more than 36 m/d. With the current surge, between January 8 and 14, 2011, the terminus advanced a maximum of 125 m, averaging nearly 21 m/d. By July 11, 2011, maximum velocities still approached 15 m per day, with maximum ice displacements of nearly 2 km and a maximum terminus advance of 1.7 km. In the 1993-1995 surge, the first evidence of surge activity was observed in April 1993, the development of a fractured ice bulge on the northwest side of the Grindle Hills. The surge front reached Bering's terminus at the end of August 1993 and left it heavily fractured. With the current surge, until July 2009, surface displacements were restricted to the area from west of, to northeast of the Grindle Hills. By November 18, 2010, the surge front reached Bering's terminus and left it more heavily fractured than in 1993. The current surge shows the same style and types of surface disruptions and deformations at the same locations as did the earlier surge. For example, in both surges, sinusoidal crevasses were first noted north of the Grindle Hills, while rifts were noted in the upper central piedmont lobe. The current surge has produced much more fracturing of the Medial Moraine Band than did the 1993-95 surge. Similarly, the extent of surface fracturing up-glacier from the piedmont lobe is significantly greater in the current surge. During the 1993-95 surge, surface expression of the surge extended about 45 km east of the western end of Juniper Island. In late July 2011, surge-related surface fractures extended nearly 90 km to the east. The Steller lobe of the Bering Glacier System has not been involved in either surge. Continued observations of the current surge, in the context of the 1993-95 surge, are providing significant insights into repeatable patterns of surging glacier behavior. Bering Glacier is an amazing natural laboratory at which to conduct these observations.

Tropical cyclone induced asymmetry of sea level surge and fall and its presentation in a storm surge model with parametric wind fields

NASA Astrophysics Data System (ADS)

Peng, Machuan; Xie, Lian; Pietrafesa, Leonard J.

The asymmetry of tropical cyclone induced maximum coastal sea level rise (positive surge) and fall (negative surge) is studied using a three-dimensional storm surge model. It is found that the negative surge induced by offshore winds is more sensitive to wind speed and direction changes than the positive surge by onshore winds. As a result, negative surge is inherently more difficult to forecast than positive surge since there is uncertainty in tropical storm wind forecasts. The asymmetry of negative and positive surge under parametric wind forcing is more apparent in shallow water regions. For tropical cyclones with fixed central pressure, the surge asymmetry increases with decreasing storm translation speed. For those with the same translation speed, a weaker tropical cyclone is expected to gain a higher AI (asymmetry index) value though its induced maximum surge and fall are smaller. With fixed RMW (radius of maximum wind), the relationship between central pressure and AI is heterogeneous and depends on the value of RMW. Tropical cyclone's wind inflow angle can also affect surge asymmetry. A set of idealized cases as well as two historic tropical cyclones are used to illustrate the surge asymmetry.

Atlantic hurricane surge response to geoengineering

DOE Office of Scientific and Technical Information (OSTI.GOV)

Moore, John C.; Grinsted, Aslak; Guo, Xiaoran

Devastating Atlantic hurricanes are relatively rare events. However their intensity and frequency in a warming world may rapidly increase by a factor of 2-7 for each degree of increase in mean global temperature. Geoengineering by stratospheric sulphate aerosol injection cools the tropics relative to the polar regions, including the hurricane main development region in the Atlantic, suggesting that geoengineering may be an effective method of controlling hurricanes. We examine this hypothesis using 8 Earth System Model simulations of climate under the GeoMIP G3 and G4 schemes that use stratospheric aerosols to reduce the radiative forcing under the RCP4.5 scenario. Globalmore » mean temperature increases are greatly ameliorated by geoengineering, and tropical temperature increases are at most half of those in RCP4.5, but sulphate injection would have to double between 2020 and 2070 to balance RCP 4.5 to nearly 10 Tg SO2 yr-1, with consequent implications for damage to stratospheric ozone. We project changes in storm frequencies using a temperature-dependent Generalized Extreme Value statistical model calibrated by historical storm surges from 1923 and observed temperatures. The numbers of storm surge events as big as the one that caused the 2005 Katrina hurricane are reduced by about 50% compared with no geoengineering, but this is only marginally statistically significant. Furthermore, when sea level rise differences at 2070 between RCP4.5 and geoengineering are factored in to coastal flood risk, we find that expected flood levels are reduced by about 40 cm for 5 year events and perhaps halved for 50 year surges.« less

Atlantic hurricane surge response to geoengineering

DOE PAGES

Moore, John C.; Grinsted, Aslak; Guo, Xiaoran; ...

2015-10-26

Devastating Atlantic hurricanes are relatively rare events. However their intensity and frequency in a warming world may rapidly increase by a factor of 2-7 for each degree of increase in mean global temperature. Geoengineering by stratospheric sulphate aerosol injection cools the tropics relative to the polar regions, including the hurricane main development region in the Atlantic, suggesting that geoengineering may be an effective method of controlling hurricanes. We examine this hypothesis using 8 Earth System Model simulations of climate under the GeoMIP G3 and G4 schemes that use stratospheric aerosols to reduce the radiative forcing under the RCP4.5 scenario. Globalmore » mean temperature increases are greatly ameliorated by geoengineering, and tropical temperature increases are at most half of those in RCP4.5, but sulphate injection would have to double between 2020 and 2070 to balance RCP 4.5 to nearly 10 Tg SO2 yr-1, with consequent implications for damage to stratospheric ozone. We project changes in storm frequencies using a temperature-dependent Generalized Extreme Value statistical model calibrated by historical storm surges from 1923 and observed temperatures. The numbers of storm surge events as big as the one that caused the 2005 Katrina hurricane are reduced by about 50% compared with no geoengineering, but this is only marginally statistically significant. Furthermore, when sea level rise differences at 2070 between RCP4.5 and geoengineering are factored in to coastal flood risk, we find that expected flood levels are reduced by about 40 cm for 5 year events and perhaps halved for 50 year surges.« less

Atlantic hurricane surge response to geoengineering

DOE Office of Scientific and Technical Information (OSTI.GOV)

Moore, John C.; Grinsted, Aslak; Guo, Xiaoran

2015-10-26

Devastating Atlantic hurricanes are relatively rare events. However their intensity and frequency in a warming world may rapidly increase by a factor of 2-7 for each degree of increase in mean global temperature. Geoengineering by stratospheric sulphate aerosol injection cools the tropics relative to the polar regions, including the hurricane main development region in the Atlantic, suggesting that geoengineering may be an effective method of controlling hurricanes. We examine this hypothesis using 8 Earth System Model simulations of climate under the GeoMIP G3 and G4 schemes that use stratospheric aerosols to reduce the radiative forcing under the RCP4.5 scenario. Globalmore » mean temperature increases are greatly ameliorated by geoengineering, and tropical temperature increases are at most half of those in RCP4.5, but sulphate injection would have to double between 2020 and 2070 to balance RCP 4.5 to nearly 10 Tg SO2 yr-1, with consequent implications for damage to stratospheric ozone. We project changes in storm frequencies using a temperature-dependent Generalized Extreme Value statistical model calibrated by historical storm surges from 1923 and observed temperatures. The numbers of storm surge events as big as the one that caused the 2005 Katrina hurricane are reduced by about 50% compared with no geoengineering, but this is only marginally statistically significant. However, when sea level rise differences at 2070 between RCP4.5 and geoengineering are factored in to coastal flood risk, we find that expected flood levels are reduced by about 40 cm for 5 year events and perhaps halved for 50 year surges.« less

Recently Patented Viral Nucleotide Sequences and Generation of Virus-Derived Vaccines.

PubMed

Venkataraman, Srividhya; Ahmad, Tauqeer; Haidar, Mounir A; Hefferon, Kathleen L

2017-01-01

With an increase in comprehension of the molecular biology of viruses, there has been a recent surge in the application of virus sequences and viral gene expression strategies towards the diagnosis and treatment of diseases. The scope of the patenting landscape has widened as a result and the current review discusses patents pertaining to live / attenuated viral vaccines. The vaccines addressed here have been developed by both conventional means as well as by the state-of-the-art genetic engineering techniques. This review also addresses the applications of these patents for clinical and biotechnological purposes. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Modeling the Origin and Possible Control of the Wealth Inequality Surge

PubMed Central

Berman, Yonatan; Shapira, Yoash; Ben-Jacob, Eshel

2015-01-01

The rapid increase of wealth inequality in the past few decades is a most disturbing social and economic issue of our time. In order to control, and even reverse that surge, its origin and underlying mechanisms should be revealed. One of the challenges in studying these mechanisms is to incorporate realistic individual dynamics in the population level in a self-consistent manner. Our theoretical approach meets the challenge by using interacting multi-agent master-equations to model the dynamics of wealth inequality. The model is solved using stochastic multi-agent iterated maps. Taking into account growth rate, return on capital, private savings and economic mobility, we were able to capture the historical dynamics of wealth inequality in the United States during the course of the 20th century. We show that the fraction of capital income in the national income and the fraction of private savings are the critical factors that govern the wealth inequality dynamics. In addition, we found that economic mobility plays a crucial role in wealth accumulation. Notably, we found that the major decrease in private savings since the 1980s could be associated primarily with the recent surge in wealth inequality and if nothing changes in this respect we predict further increase in wealth inequality in the future. However, the 2007–08 financial crisis brought an opportunity to restrain the wealth inequality surge by increasing private savings. If this trend continues, it may lead to prevention, and even reversing, of the ongoing inequality surge. PMID:26107388

Modeling the Origin and Possible Control of the Wealth Inequality Surge.

PubMed

Berman, Yonatan; Shapira, Yoash; Ben-Jacob, Eshel

2015-01-01

The rapid increase of wealth inequality in the past few decades is a most disturbing social and economic issue of our time. In order to control, and even reverse that surge, its origin and underlying mechanisms should be revealed. One of the challenges in studying these mechanisms is to incorporate realistic individual dynamics in the population level in a self-consistent manner. Our theoretical approach meets the challenge by using interacting multi-agent master-equations to model the dynamics of wealth inequality. The model is solved using stochastic multi-agent iterated maps. Taking into account growth rate, return on capital, private savings and economic mobility, we were able to capture the historical dynamics of wealth inequality in the United States during the course of the 20th century. We show that the fraction of capital income in the national income and the fraction of private savings are the critical factors that govern the wealth inequality dynamics. In addition, we found that economic mobility plays a crucial role in wealth accumulation. Notably, we found that the major decrease in private savings since the 1980s could be associated primarily with the recent surge in wealth inequality and if nothing changes in this respect we predict further increase in wealth inequality in the future. However, the 2007-08 financial crisis brought an opportunity to restrain the wealth inequality surge by increasing private savings. If this trend continues, it may lead to prevention, and even reversing, of the ongoing inequality surge.

Right Ventricular Outflow Tract Stenting in Tetralogy of Fallot Infants With Risk Factors for Early Primary Repair.

PubMed

Sandoval, Juan Pablo; Chaturvedi, Rajiv R; Benson, Lee; Morgan, Gareth; Van Arsdell, Glen; Honjo, Osami; Caldarone, Christopher; Lee, Kyong-Jin

2016-12-01

Tetralogy of Fallot with cyanosis requiring surgical repair in early infancy reflects poor anatomy and is associated with more clinical instability and longer hospitalization than those who can be electively repaired later. We bridged symptomatic infants with risk factors for early primary repair by right ventricular outflow tract stenting (stent). Four groups of tetralogy of Fallot with confluent central pulmonary arteries were studied: stent group (n=42), primary repair (aged <3 months) with pulmonary stenosis (early-PS group; n=44), primary repair (aged <3 months) with pulmonary atresia (early-PA group; n=49), and primary repair between 3 and 11 months of age (surg>3mo group; n=45). Stent patients had the smallest pulmonary arteries with a median (95% credible intervals) Nakata index (mm 2 /m 2 ) of 79 (66-85) compared with the early-PA 139 (129-154), early-PS 136 (121-153), and surg>3mo 167 (153-200) groups. Only stent infants required unifocalization of aortopulmonary collaterals (17%). Stent and early-PA infants had younger age and lower weight than early-PS infants. Stent infants had the most multiple comorbidities. Stenting allowed deferral of complete surgical repair to an age (6 months), weight (6.3 [5.8-7.0] kg), and Nakata index (147 [132-165]) similar to the low-risk surg>3mo group. The 3 early treatment groups had similar intensive care unit/hospital stays and high reintervention rates in the first 12 months after repair, compared with the surg>3mo group. Right ventricular outflow tract stenting of symptomatic tetralogy of Fallot with poor anatomy (small pulmonary arteries) and adverse factors (multiple comorbidities, low weight) relieves cyanosis and defers surgical repair. This allowed pulmonary arterial and somatic growth with clinical results comparable to early surgical repair in more favorable patients. © 2016 American Heart Association, Inc.

The eSurge-Venice project: altimeter and scatterometer satellite data to improve the storm surge forecasting in the city of Venice

NASA Astrophysics Data System (ADS)

Zecchetto, Stefano; De Biasio, Francesco; Umgiesser, Georg; Bajo, Marco; Vignudelli, Stefano; Papa, Alvise; Donlon, Craig; Bellafiore, Debora

2013-04-01

On the framework of the Data User Element (DUE) program, the European Space Agency is funding a project to use altimeter Total Water Level Envelope (TWLE) and scatterometer wind data to improve the storm surge forecasting in the Adriatic Sea and in the city of Venice. The project will: a) Select a number of Storm Surge Events occurred in the Venice lagoon in the period 1999-present day b) Provide the available satellite Earth Observation (EO) data related to the Storm Surge Events, mainly satellite winds and altimeter data, as well as all the available in-situ data and model forecasts c) Provide a demonstration Near Real Time service of EO data products and services in support of operational and experimental forecasting and warning services d) Run a number of re-analysis cases, both for historical and contemporary storm surge events, to demonstrate the usefulness of EO data The re-analysis experiments, based on hindcasts performed by the finite element 2-D oceanographic model SHYFEM (https://sites.google.com/site/shyfem/), will 1. use different forcing wind fields (calibrated and not calibrated with satellite wind data) 2. use Storm Surge Model initial conditions determined from altimeter TWLE data. The experience gained working with scatterometer and Numerical Weather Prediction (NWP) winds in the Adriatic Sea tells us that the bias NWP-Scatt wind is negative and spatially and temporally not uniform. In particular, a well established point is that the bias is higher close to coasts then offshore. Therefore, NWP wind speed calibration will be carried out on each single grid point in the Adriatic Sea domain over the period of a Storm Surge Event, taking into account of existing published methods. Point #2 considers two different methodologies to be used in re-analysis tests. One is based on the use of the TWLE values from altimeter data in the Storm Surge Model (SSM), applying data assimilation methodologies and trying to optimize the initial conditions of the simulation.The second possibility is an indirect exploitation of the TWLE data from altimeter in an ensemble-like framework, obtained by slight variations of the external forcing. In this case the wind data from NWP models will be weakly altered (shifted in phase), the drag coefficient will be modified, and the initial condition of the model slightly shifted in time to account for the uncertainty of these factors. This contribution will illustrate the geophysical context of work and outline the results.

Water level observations in mangrove swamps during two hurricanes in Florida

USGS Publications Warehouse

Krauss, K.W.; Doyle, T.W.; Doyle, T.J.; Swarzenski, C.M.; From, A.S.; Day, Richard H.; Conner, W.H.

2009-01-01

Little is known about the effectiveness of mangroves in suppressing water level heights during landfall of tropical storms and hurricanes. Recent hurricane strikes along the Gulf Coast of the United States have impacted wetland integrity in some areas and hastened the need to understand how and to what degree coastal forested wetlands confer protection by reducing the height of peak water level. In recent years, U.S. Geological Survey Gulf Coast research projects in Florida have instrumented mangrove sites with continuous water level recorders. Our ad hoc network of water level recorders documented the rise, peak, and fall of water levels (?? 0.5 hr) from two hurricane events in 2004 and 2005. Reduction of peak water level heights from relatively in-line gages associated with one storm surge event indicated that mangrove wetlands can reduce water level height by as much as 9.4 cm/km inland over intact, relatively unchannelized expanses. During the other event, reductions were slightly less for mangroves along a river corridor. Estimates of water level attenuation were within the range reported in the literature but erred on the conservative side. These synoptic data from single storm events indicate that intact mangroves may support a protective role in reducing maximum water level height associated with surge.

Communicating Storm Surge Forecast Uncertainty

NASA Astrophysics Data System (ADS)

Troutman, J. A.; Rhome, J.

2015-12-01

When it comes to tropical cyclones, storm surge is often the greatest threat to life and property along the coastal United States. The coastal population density has dramatically increased over the past 20 years, putting more people at risk. Informing emergency managers, decision-makers and the public about the potential for wind driven storm surge, however, has been extremely difficult. Recently, the Storm Surge Unit at the National Hurricane Center in Miami, Florida has developed a prototype experimental storm surge watch/warning graphic to help communicate this threat more effectively by identifying areas most at risk for life-threatening storm surge. This prototype is the initial step in the transition toward a NWS storm surge watch/warning system and highlights the inundation levels that have a 10% chance of being exceeded. The guidance for this product is the Probabilistic Hurricane Storm Surge (P-Surge) model, which predicts the probability of various storm surge heights by statistically evaluating numerous SLOSH model simulations. Questions remain, however, if exceedance values in addition to the 10% may be of equal importance to forecasters. P-Surge data from 2014 Hurricane Arthur is used to ascertain the practicality of incorporating other exceedance data into storm surge forecasts. Extracting forecast uncertainty information through analyzing P-surge exceedances overlaid with track and wind intensity forecasts proves to be beneficial for forecasters and decision support.

Forecasting of Storm-Surge Floods Using ADCIRC and Optimized DEMs

NASA Technical Reports Server (NTRS)

Valenti, Elizabeth; Fitzpatrick, Patrick

2006-01-01

Increasing the accuracy of storm-surge flood forecasts is essential for improving preparedness for hurricanes and other severe storms and, in particular, for optimizing evacuation scenarios. An interactive database, developed by WorldWinds, Inc., contains atlases of storm-surge flood levels for the Louisiana/Mississippi gulf coast region. These atlases were developed to improve forecasting of flooding along the coastline and estuaries and in adjacent inland areas. Storm-surge heights depend on a complex interaction of several factors, including: storm size, central minimum pressure, forward speed of motion, bottom topography near the point of landfall, astronomical tides, and, most importantly, maximum wind speed. The information in the atlases was generated in over 100 computational simulations, partly by use of a parallel-processing version of the ADvanced CIRCulation (ADCIRC) model. ADCIRC is a nonlinear computational model of hydrodynamics, developed by the U.S. Army Corps of Engineers and the US Navy, as a family of two- and three-dimensional finite-element-based codes. It affords a capability for simulating tidal circulation and storm-surge propagation over very large computational domains, while simultaneously providing high-resolution output in areas of complex shoreline and bathymetry. The ADCIRC finite-element grid for this project covered the Gulf of Mexico and contiguous basins, extending into the deep Atlantic Ocean with progressively higher resolution approaching the study area. The advantage of using ADCIRC over other storm-surge models, such as SLOSH, is that input conditions can include all or part of wind stress, tides, wave stress, and river discharge, which serve to make the model output more accurate. To keep the computational load manageable, this work was conducted using only the wind stress, calculated by using historical data from Hurricane Camille, as the input condition for the model. Hurricane storm-surge simulations were performed on an eight-node Linux computer cluster. Each node contained dual 2-GHz processors, 2GB of memory, and a 40GB hard drive. The digital elevation model (DEM) for this region was specified using a combination of Navy data (over water), NOAA data (for the coastline), and optimized Interferometric Synthetic Aperture Radar data (over land). This high-resolution topographical data of the Mississippi coastal region provided the ADCIRC model with improved input with which to calculate improved storm-surge forecasts.

Developments in a centrifugal compressor surge control -- a technology assessment

DOE Office of Scientific and Technical Information (OSTI.GOV)

Botros, K.K.; Henderson, J.F.

1994-04-01

There are a number of surge control schemes in current use for centrifugal compressors employed in natural gas transmission systems. Basically, these schemes consist of a set of detection devices that either anticipate surge or detect it at its inception, and a set of control devices that act to prevent surge from occurring. A patent search was conducted in an attempt to assess the level and direction of technology development over the last 20 years and to define the focus for future R D activities. In addition, the paper presents the current state of technology in three areas: surge control,more » surge detection, and surge suppression. Patent data obtained from on-line databases showed that most of the emphasis has been on surge control rather than on detection and control and that the current trend in surge control will likely continue toward incremental improvement of a basic or conventional surge control strategy. Various surge suppression techniques can be grouped in two categories: (1) those that are focused on better compressor interior design, and (2) others that attempt to suppress surge by external and operational means.« less

Surges of outlet glaciers from the Drangajökull ice cap, northwest Iceland

NASA Astrophysics Data System (ADS)

Brynjólfsson, Skafti; Schomacker, Anders; Korsgaard, Niels J.; Ingólfsson, Ólafur

2016-09-01

Surface elevation and volume changes of the Drangajökull surge-type glaciers, Reykjarfjarðarjökull and Leirufjarðarjökull, were studied by comparing digital elevation models that pre-date and post-date their most recent surges. Annual glacier-frontal measurements were used to estimate average ice velocities during the last surge of the glaciers. The observations show a distinct ice discharge, most of which was from the upper reservoir areas, down to the receiving areas during the surges. The surface draw-down in the reservoir areas was usually 10-30 m during the surges, while the thickening of the receiving areas was significantly more variable, on the order of 10-120 m. Despite a negative geodetic net mass balance derived from the digital elevation models, the reservoir areas have been gaining mass since the surge terminations. This surface thickening along with considerable ablation of the receiving areas will most likely return the glacier surface profiles to the pre-surge stage. Our results indicate that (a) greatest surface thinning in the upper reservoir areas of Drangajökull rather than proximal to the equilibrium line during Vatnajökull surges and (b) development of Drangajökull surges that resembles Svalbard surge-type glaciers rather than Vatnajökull surge-type glaciers. The contrasting surge characteristics could be explained by differences in glacier geometry, topography and substratum of the Drangajökull and Vatnajökull surge-type glaciers.

Risk assessment of storm surge disaster based on numerical models and remote sensing

NASA Astrophysics Data System (ADS)

Liu, Qingrong; Ruan, Chengqing; Zhong, Shan; Li, Jian; Yin, Zhonghui; Lian, Xihu

2018-06-01

Storm surge is one of the most serious ocean disasters in the world. Risk assessment of storm surge disaster for coastal areas has important implications for planning economic development and reducing disaster losses. Based on risk assessment theory, this paper uses coastal hydrological observations, a numerical storm surge model and multi-source remote sensing data, proposes methods for valuing hazard and vulnerability for storm surge and builds a storm surge risk assessment model. Storm surges in different recurrence periods are simulated in numerical models and the flooding areas and depth are calculated, which are used for assessing the hazard of storm surge; remote sensing data and GIS technology are used for extraction of coastal key objects and classification of coastal land use are identified, which is used for vulnerability assessment of storm surge disaster. The storm surge risk assessment model is applied for a typical coastal city, and the result shows the reliability and validity of the risk assessment model. The building and application of storm surge risk assessment model provides some basis reference for the city development plan and strengthens disaster prevention and mitigation.

Genetics Home Reference: congenital diaphragmatic hernia

MedlinePlus

... Tibboel D, de Klein A, Lee B, Scott DA. Genetic factors in congenital diaphragmatic hernia. Am J ... 2009.08.004. Review. Citation on PubMed Scott DA. Genetics of congenital diaphragmatic hernia. Semin Pediatr Surg. ...

Neuroendocrine modulation and repercussions of female reproductive aging.

PubMed

Wise, Phyllis M; Smith, Matthew J; Dubal, Dena B; Wilson, Melinda E; Rau, Shane W; Cashion, Adrienne B; Böttner, Martina; Rosewell, Katherine L

2002-01-01

The menopause marks the end of a woman's reproductive life. During the postmenopausal period, plasma estrogen concentrations decrease dramatically and remain low for the rest of her life, unless she chooses to take hormone replacement therapy. During the past 20 years, we have learned that changes in the central nervous system are associated with and may influence the timing of the menopause in women. Recently, it has become clear that estrogens act on more than just the hypothalamus, pituitary, ovary, and other reproductive organs. In fact, they play roles in a wide variety of nonreproductive functions. With the increasing life span of humans from approximately 50 to 80 years and the relatively fixed age of the menopause, a larger number of women will spend over one third of their lives in the postmenopausal state. It is not surprising that interest has increased in factors that govern the timing of the menopause and the repercussions of the lack of estrogen on multiple aspects of women's health. We have used animal models to better understand the complex interactions between the ovary and the brain that lead to the menopause and the repercussions of the hypoestrogenic state. Our results show that when rats reach middle age, the patterns and synchrony of multiple neurochemical events that are critical to the preovulatory gonadotropin-releasing hormone (GnRH) surge undergo subtle changes. The precision of rhythmic pattern of neurotransmitter dynamics depends on the presence of estradiol. Responsiveness to this hormone decreases in middle-aged rats. The lack of precision in the coordination in the output of neural signals leads to a delay and attenuation of the luteinizing hormone surge, which lead to irregular estrous cyclicity and, ultimately, to the cessation of reproductive cycles. We also have examined the impact of the lack of estrogen on the vulnerability of the brain to injury. Our work establishes that the absence of estradiol increases the extent of cell death after stroke-like injury and that treatment with low physiological levels of estradiol are profoundly neuroprotective. We have begun to explore the cellular and molecular mechanisms that underlie this novel nonreproductive action of estrogens. In summary, our studies show that age-related changes in the ability of estradiol to coordinate the neuroendocrine events that lead to regular preovulatory GnRH surges contribute to the onset of irregular estrous cycles and eventually to acyclicity. Furthermore, we have shown that the lack of estradiol increases the vulnerability of the brain to injury and neurodegeneration.

H{α} Surges Aroused by Newly-emerging Satellite Bipolar Magnetic Field

NASA Astrophysics Data System (ADS)

Wang, J. F.; Zhou, T. H.; Ji, H. S.

2013-07-01

An Hα surge event occurred at AR NOAA 11259 on 2011 July 22. According to the BBSO (Big Bear Solar Observatory) Hα line-center observations, three surges continuously ejected from the same region to the north of the main-sunspot of AR 11259. All of surges ejected along a straight trajectory, and looked like the reversed Eiffel Tower. The first and second surges had the same process. Two bright points firstly appeared to the north of the main-sunspot. After several minutes, a surge appeared between the two bright points, and then rapidly ejected when the two points got most brightness.When the surge reached the maximum height, it disappeared quickly. However, the third surge appeared without bright points, and its height was only half of the others. Compared with SDO/HMI (Solar Dynamics Observatory/Helioseismic and Magnetic Imager) line-of-sight magnetogram, more than one hour before the first surge appeared, a satellite bipolar magnetic field emerged from the surge-ejection region. The newly-emerging positive magnetic flux showed a distinct decrease several minutes earlier than the ejection of the surges. We assumed that the surges was associated with the reconnection between the newly-emerging bipolar magnetic field and the existing (sunspot) magnetic field.

New evidence of surge-type glaciers in the Central Andes of Argentina and Chile

NASA Astrophysics Data System (ADS)

Bolch, T.; Falaschi, D.; Lenzano, M. G.; Tadono, T.; Lenzano, L. E.

2017-12-01

In contrast to the large surge-type glacier clusters widely known for several mountain ranges around the world, the presence of surging glaciers in the Andes has been historically seen as marginal. Based on the analysis of satellite imagery and DEM differencing, coupled with aerial archival data, we identified 21 surge-type glaciers in the Central Andes, out of which four of them are confirmed surge-type, six are very-probable surge-type, and eleven are possible surge-type. The geodetic mass balance estimation of 12 glaciers for the 2000-2011 period, which encompasses the latest surge events, mostly showed either moderately negative or positive patterns (-0.5 to 0.3 m w.e. a-1). Additionally, we calculated maximum surface velocities of 6.3 ±1.9 m d-1 and 3.5 ±1.2 m d-1 for the Piuquenes and Noreste del Cerro Alto glaciers during the latest two identifiable surge events (1985-1987 and 2003-2007), and preliminarily determined surge cycles of 10 and 20 years for these two glaciers, respectively. The synchronicity of recent and past glacier surges and the coincidence with anomalously cold, snowy periods point out to a common climatic control over glacier surges in this region.

Climate projections of spatial variations in coastal storm surges along the Gulf of Mexico and U.S. east coast

NASA Astrophysics Data System (ADS)

Yao, Zhigang; Xue, Zuo; He, Ruoying; Bao, Xianwen; Xie, Jun; Ge, Qian

2017-02-01

Using statistically downscaled atmospheric forcing, we performed a numerical investigation to evaluate future climate's impact on storm surges along the Gulf of Mexico and U.S. east coast. The focus is on the impact of climatic changes in wind pattern and surface pressure while neglecting sea level rise and other factors. We adapted the regional ocean model system (ROMS) to the study region with a mesh grid size of 7-10 km in horizontal and 18 vertical layers. The model was validated by a hindcast of the coastal sea levels in the winter of 2008. Model's robustness was confirmed by the good agreement between model-simulated and observed sea levels at 37 tidal gages. Two 10-year forecasts, one for the IPCC Pre-Industry (PI) and the other for the A1FI scenario, were conducted. The differences in model-simulated surge heights under the two climate scenarios were analyzed. We identified three types of responses in extreme surge heights to future climate: a clear decrease in Middle Atlantic Bight, an increase in the western Gulf of Mexico, and non-significant response for the remaining area. Such spatial pattern is also consistent with previous projections of sea surface winds and ocean wave heights.

Storm surges - a globally distributed risk, and the case of Hamburg (Invited)

NASA Astrophysics Data System (ADS)

von Storch, H.

2010-12-01

For most coasts, storm surges represent the major geo risk. A map of these risks shows that the phenomenon is really a global phenomenon. However, when discussing dynamics, risks, adaptation, future perspectives as well as aggravating local factors, the situation is mostly perceived as a regional or even local phenomenon. In the talk first the different manifestations of storm surges, mainly at mid latitudes and in the tropics are discussed; the historical perceptions of such events are touched upon, projection for the future presented and issues of management and adaptation discussed. In a second part, a specific situation is discussed, namely the case of Hamburg since 1750. This case is particularly interesting, because specific analysis has been done for past variability, possible future developments; local perceptions of risk and un-conventional mitigation measures. For the time prior to 1850, coastal defence failure was a regular phenomenon; from about 1850-1960 coastal defence was hardly challenged, and after the 1962 storm surge heights rose to levels never recorded before. The most likely causes for this change are modifications of the Elbe estuary, related to coastal defence and improving the shipping channel. Anthropogenic climate change may lead in the future to even higher storm surges (mainly because of increased sea level). While for the foreseeable future, conventional measures will be sufficient for ensuring coastal defence, a mitigation option of local mitigation of high water levels seems to be available. This may be achieved though the "tidal Elbe project", which was designed to reduce upstream river sediment transport.

Centrifugal Compressor Surge Controlled

NASA Technical Reports Server (NTRS)

Skoch, Gary J.

2003-01-01

It shows the variation in compressor mass flow with time as the mass flow is throttled to drive the compressor into surge. Surge begins where wide variations in mass flow occur. Air injection is then turned on to bring about a recovery from the initial surge condition and stabilize the compressor. The throttle is closed further until surge is again initiated. Air injection is increased to again recover from the surge condition and stabilize the compressor.

Advances in using satellite altimetry to observe storm surge

NASA Astrophysics Data System (ADS)

Han, Guoqi

2017-04-01

Storm surges are the major cause for coastal flooding, resulting in catastrophic damage to properties and loss of life in coastal communities. Thus it is important to utilize new technology to enhance our capabilities of observing storm surges and ultimately to improve our capacity for forecasting storm surges and mitigating damage and loss. In this talk we first review traditional methods of monitoring storm surges. We then provide examples of storm surges observed by nadir satellite altimetry, during Hurricane Sandy and Igor, as well as typhoon and cyclone events. We further evaluate satellite results against tide-gauge data and explain storm surge features. Finally, we discuss the potential of a wide-swath altimetry mission, the Surface Water and Ocean Topography (SWOT), for observing storm surges.

Mapping and Visualization of Storm-Surge Dynamics for Hurricane Katrina and Hurricane Rita

USGS Publications Warehouse

Gesch, Dean B.

2009-01-01

The damages caused by the storm surges from Hurricane Katrina and Hurricane Rita were significant and occurred over broad areas. Storm-surge maps are among the most useful geospatial datasets for hurricane recovery, impact assessments, and mitigation planning for future storms. Surveyed high-water marks were used to generate a maximum storm-surge surface for Hurricane Katrina extending from eastern Louisiana to Mobile Bay, Alabama. The interpolated surface was intersected with high-resolution lidar elevation data covering the study area to produce a highly detailed digital storm-surge inundation map. The storm-surge dataset and related data are available for display and query in a Web-based viewer application. A unique water-level dataset from a network of portable pressure sensors deployed in the days just prior to Hurricane Rita's landfall captured the hurricane's storm surge. The recorded sensor data provided water-level measurements with a very high temporal resolution at surveyed point locations. The resulting dataset was used to generate a time series of storm-surge surfaces that documents the surge dynamics in a new, spatially explicit way. The temporal information contained in the multiple storm-surge surfaces can be visualized in a number of ways to portray how the surge interacted with and was affected by land surface features. Spatially explicit storm-surge products can be useful for a variety of hurricane impact assessments, especially studies of wetland and land changes where knowledge of the extent and magnitude of storm-surge flooding is critical.

Soft-Starting Power-Factor Motor Controller

NASA Technical Reports Server (NTRS)

Nola, F. J.

1983-01-01

Three-phase power-factor controller with soft start is based on earlier version that does not control starting transients. Additional components serve to turn off "run" command signal and substitute gradual startup command signal during preset startup interval. Improved controller reduces large current surge that usually accompanies starting. Controller applies power smoothly, without causing motor vibrations.

Holocene sea-level variations and geomorphological response: An example from northern Brittany (France)

NASA Astrophysics Data System (ADS)

Regnauld, H.; Jennings, S.; Delaney, C.; Lemasson, L.

In northern Brittany an important geomorphological response to Holocene sea-level rise has been the development of coastal dunes with associated lagoons and marshes. At Anse du Verger, a marsh has formed behind a dune system which has been developing in situ for the last 4000 years. The lithostratigraphy of the marsh comprises extensive peat formation, with sands, silts and occasional sand lenses, the latter probably associated with storm surges. The sequence dates from 10,320±120 BP. After 3000 BP, flood episodes on the marsh are more common, while the upper marsh deposits can be correlated with the recent period of dune building. Prehistoric artifacts (remains of cooking implements) have been found on a cliff to the east of the marsh and are buried by washover deposits, which indicates a sudden abandonment of a settlement possibly due to a storm surge soon after 2460±80 BP. Surge levels are proposed as a controlling factor on dune crest elevation.

Comparative Analysis of Glaciers in the Chugach-St.-Elias Mountains

NASA Astrophysics Data System (ADS)

Herzfeld, U. C.; Mayer, H.

2003-12-01

The phenomenon of glacier surges has to date been studied for only relatively few examples. 136 of the 204 surge-type glaciers in North America listed by Post (1969) are located in the St. Elias Mountains. In August 2003 we increased our data inventory of observations on surge glaciers by collecting material for 19 glaciers in the Glacier Bay area and neighboring regions in the eastern St. Elias Mountains, including 6 surge-type glaciers (Carroll, Rendu, Ferris, Grand Pacific, Margerie, and Johns Hopkins Glaciers). Analyses utilize digital video and photographic data, satellite data and GPS data. Geostatistical classification parameters and algebraic parameters characteristic of surge motions are derived for selected glaciers. During the 1993-1995 surge of Bering Glacier the entire surface of Alaska's longest glacier was crevassed and could be segmented into several dynamic provinces, where patterns changed as the surge progressed and the affected areas expanded downglacier and upglacier, finally affecting the Bagley Ice Field. The middle moraine of Grand Pacific and Ferris Glaciers is pushed over to the Grand Pacific side, caused by a recent surge of the heavily crevassed Ferris Glacier. The front of Johns Hopkins Glacier advances, as its lower reaches are affected by a surge. The surge history of Bering Glacier goes back to the Holocene, whereas Carroll and Rendu Glaciers have surged only 3-4 times. These observations pose questions on the possible relationship between surge dynamics and climatic changes.

7 CFR 58.218 - Surge tanks.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 7 Agriculture 3 2012-01-01 2012-01-01 false Surge tanks. 58.218 Section 58.218 Agriculture....218 Surge tanks. If surge tanks are used for hot milk, and temperatures of product including foam being held in the surge tank during processing, is not maintained at a minimum of 150 °F, then two or...

7 CFR 58.218 - Surge tanks.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 7 Agriculture 3 2011-01-01 2011-01-01 false Surge tanks. 58.218 Section 58.218 Agriculture....218 Surge tanks. If surge tanks are used for hot milk, and temperatures of product including foam being held in the surge tank during processing, is not maintained at a minimum of 150 °F, then two or...

7 CFR 58.218 - Surge tanks.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 3 2010-01-01 2010-01-01 false Surge tanks. 58.218 Section 58.218 Agriculture....218 Surge tanks. If surge tanks are used for hot milk, and temperatures of product including foam being held in the surge tank during processing, is not maintained at a minimum of 150 °F, then two or...

7 CFR 58.218 - Surge tanks.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 7 Agriculture 3 2013-01-01 2013-01-01 false Surge tanks. 58.218 Section 58.218 Agriculture....218 Surge tanks. If surge tanks are used for hot milk, and temperatures of product including foam being held in the surge tank during processing, is not maintained at a minimum of 150 °F, then two or...

7 CFR 58.218 - Surge tanks.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 7 Agriculture 3 2014-01-01 2014-01-01 false Surge tanks. 58.218 Section 58.218 Agriculture....218 Surge tanks. If surge tanks are used for hot milk, and temperatures of product including foam being held in the surge tank during processing, is not maintained at a minimum of 150 °F, then two or...

Quantifying the Mass Flux, Erosion Rates and Geomorphological Impact of Surging Karakoram Glaciers

NASA Astrophysics Data System (ADS)

Quincey, D. J.; Glasser, N. F.; King, O.

2017-12-01

Surge-type glaciers switch between phases of rapid and slow flow on timescales of a few years to decades. Here, we describe glacier-surface debris changes, surface-elevation changes and velocity changes through surges lasting five to ten years on ten different Karakoram glaciers (Khurdopin, Gasherbrum, Kunyang, Braldu, Chong Khumdan, Qiogeli, Saxintulu, Shakesiga, Skamri and Unnamed). We use these data to characterise their geomorphological imprint on the landscape, calculate a minimum mass flux for each of the surges and provide first-order estimates of bed erosion rates. Surface debris transport through the surges includes widespread rearrangement of surface debris features, folding and the concentration of debris near glacier termini, confluences and margins. Ice and debris-flux is partly dependent on the style of the surge, and in particular whether a surge-front propagates down-glacier during the active phase. Erosion rates also depend on the style and longevity of the surge, but are largely comparable between each of the studied datasets. We conclude by estimating the geomorphic work undertaken during surge events in comparison to work carried out by non-surging glaciers in the same region.

X-Ray Form Factor, Attenuation and Scattering Tables

National Institute of Standards and Technology Data Gateway

SRD 66 X-Ray Form Factor, Attenuation and Scattering Tables (Web, free access)   This database collects tables and graphs of the form factors, the photoabsorption cross section, and the total attenuation coefficient for any element (Z <= 92).

Damping factor estimation using spin wave attenuation in permalloy film

DOE Office of Scientific and Technical Information (OSTI.GOV)

Manago, Takashi, E-mail: manago@fukuoka-u.ac.jp; Yamanoi, Kazuto; Kasai, Shinya

2015-05-07

Damping factor of a Permalloy (Py) thin film is estimated by using the magnetostatic spin wave propagation. The attenuation lengths are obtained by the dependence of the transmission intensity on the antenna distance, and decrease with increasing magnetic fields. The relationship between the attenuation length, damping factor, and external magnetic field is derived theoretically, and the damping factor was determined to be 0.0063 by fitting the magnetic field dependence of the attenuation length, using the derived equation. The obtained value is in good agreement with the general value of Py. Thus, this estimation method of the damping factor using spinmore » waves attenuation can be useful tool for ferromagnetic thin films.« less

Modelling the 2013 Typhoon Haiyan storm surge: Effect of waves, offshore winds, tide phase, and translation speed

NASA Astrophysics Data System (ADS)

Bilgera, P. H. T.

2015-12-01

Super Typhoon Haiyan, with wind speeds exceeding 300 km h-1 (160 knots) generated a storm surge in San Pedro Bay reaching heights of more than 6m in Tacloban City. Delft Dashboard (DDB), an open-source standalone Matlab based graphical user interface linked to the FLOW and WAVE modeling software of Deltares, was used to develop a coupled flow and wave storm surge model to understand the Typhoon Haiyan storm surge development and propagation. Various experiments were designed to determine the effect of waves, the occurrence of offshore winds prior to the surge, tidal phase, and typhoon translation speed on the surge height. Wave coupling decreased the surge height by about 0.5m probably due to energy dissipation from white capping, bottom friction, and depth-induced breaking. Offshore-directed winds before the arrival of the storm eye resulted to receding of the water level in San Pedro and Cancabato Bay, corroborated by eyewitness and tide gauge data. The experiment wherein the offshore winds were removed resulted to no water receding and a surge with a smaller and gentler surge front, pointing to the importance of the initial water level drawdown in contributing to the destructive power of the wave front. With regard to tides, the effect in Tacloban was actually neither linear nor additive to the surge, with higher surge coincident to low tides and lower surge coincident to high tides. Lastly, the model run with typhoon having a slower translation speed than Haiyan was found to generate higher surges.

Modelling the 2013 Typhoon Haiyan Storm Surge: Effect of Waves, Offshore Winds, Tide Phase, and Translation Speed

NASA Astrophysics Data System (ADS)

Bilgera, P. H. T.; Villanoy, C.; Cabrera, O.

2016-02-01

Super Typhoon Haiyan, with wind speeds exceeding 300 km h-1 (160 knots) generated a storm surge in San Pedro Bay reaching heights of more than 6m in Tacloban City. Delft Dashboard (DDB), an open-source standalone Matlab based graphical user interface linked to the FLOW and WAVE modeling software of Deltares, was used to develop a coupled flow and wave storm surge model to understand the Typhoon Haiyan storm surge development and propagation. Various experiments were designed to determine the effect of waves, the occurrence of offshore winds prior to the surge, tidal phase, and typhoon translation speed on the surge height. Wave coupling decreased the surge height by about 0.5m probably due to energy dissipation from white capping, bottom friction, and depth-induced breaking. Offshore-directed winds before the arrival of the storm eye resulted to receding of the water level in San Pedro and Cancabato Bay, corroborated by eyewitness and tide gauge data. The experiment wherein the offshore winds were removed resulted to no water receding and a surge with a smaller and gentler surge front, pointing to the importance of the initial water level drawdown in contributing to the destructive power of the wave front. With regard to tides, the effect in Tacloban was actually neither linear nor additive to the surge, with higher surge coincident to low tides and lower surge coincident to high tides. Lastly, the model run with typhoon having a slower translation speed than Haiyan was found to generate higher surges.

Emergency department surge capacity: recommendations of the Australasian Surge Strategy Working Group.

PubMed

Bradt, David A; Aitken, Peter; FitzGerald, Gerry; Swift, Roger; O'Reilly, Gerard; Bartley, Bruce

2009-12-01

For more than a decade, emergency medicine (EM) organizations have produced guidelines, training, and leadership for disaster management. However, to date there have been limited guidelines for emergency physicians (EPs) needing to provide a rapid response to a surge in demand. The aim of this project was to identify strategies that may guide surge management in the emergency department (ED). A working group of individuals experienced in disaster medicine from the Australasian College for Emergency Medicine Disaster Medicine Subcommittee (the Australasian Surge Strategy Working Group) was established to undertake this work. The Working Group used a modified Delphi technique to examine response actions in surge situations and identified underlying assumptions from disaster epidemiology and clinical practice. The group then characterized surge strategies from their corpus of experience; examined them through available relevant published literature; and collated these within domains of space, staff, supplies, and system operations. These recommendations detail 22 potential actions available to an EP working in the context of surge, along with detailed guidance on surge recognition, triage, patient flow through the ED, and clinical goals and practices. The article also identifies areas that merit future research, including the measurement of surge capacity, constraints to strategy implementation, validation of surge strategies, and measurement of strategy impacts on throughput, cost, and quality of care.

Surge detection on an automotive turbocharger during transient phases

NASA Astrophysics Data System (ADS)

Deligant, M.; Danlos, A.; Podevin, P.; Clenci, A.; Guilain, S.

2017-10-01

The surge limit on automotive turbocharger needs to be avoided to prevent operations with pressure and mass flow oscillations. Mild surge is accompanied by noise which is disturbing. Deep surge can cause significant loss of engine power and severe drivability issues. It is necessary to know the stationary limit in order to match a turbocharger with an engine, ensuring enough surge margin. However, this choice does not guarantee surge free operation during transient functioning. In this paper, the surge onset of a compressor while closing a downstream valve is studied. Various tests have been carried out varying the closing time, the position of the initial operating point and the volume of the circuit. The inlet and outlet signals of physical parameters are analyzed with spectral and temporal methods in order to define the instant of the surge occurrence.

Biochemical factors modulating female genital sexual arousal physiology.

PubMed

Traish, Abdulmaged M; Botchevar, Ella; Kim, Noel N

2010-09-01

Female genital sexual arousal responses are complex neurophysiological processes consisting of central and peripheral components that occur following sexual stimulation. The peripheral responses in sexual arousal include genital vasocongestion, engorgement and lubrication resulting from a surge of vaginal and clitoral blood flow. These hemodynamic events are mediated by a host of neurotransmitters and vasoactive agents. To discuss the role of various biochemical factors modulating female genital sexual arousal responses. A comprehensive literature review was conducted using the PubMed database and citations were selected, based on topical relevance, and examined for study methodology and major findings. Data from peer-reviewed publications. Adrenergic as well as non-adrenergic non-cholinergic neurotransmitters play an important role in regulating genital physiological responses by mediating vascular and non-vascular smooth muscle contractility. Vasoactive peptides and neuropeptides also modulate genital sexual responses by regulating vascular and non-vascular smooth muscle cells and epithelial function. The endocrine milieu, particularly sex steroid hormones, is critical in the maintenance of tissue structure and function. Reduced levels of estrogens and androgen are associated with dramatic alterations in genital tissue structure, including the nerve network, as well as the response to physiological modulators. Furthermore, estrogen and androgen deficiency is associated with reduced expression of sex steroid receptors and most importantly with attenuated genital blood flow and lubrication in response to pelvic nerve stimulation. This article provides an integrated framework describing the physiological and molecular basis of various pathophysiological conditions associated with female genital sexual arousal dysfunction. © 2010 International Society for Sexual Medicine.

Four faces of baroreflex failure: hypertensive crisis, volatile hypertension, orthostatic tachycardia, and malignant vagotonia

NASA Technical Reports Server (NTRS)

Ketch, Terry; Biaggioni, Italo; Robertson, RoseMarie; Robertson, David

2002-01-01

BACKGROUND: The baroreflex normally serves to buffer blood pressure against excessive rise or fall. Baroreflex failure occurs when afferent baroreceptive nerves or their central connections become impaired. In baroreflex failure, there is loss of buffering ability, and wide excursions of pressure and heart rate occur. Such excursions may derive from endogenous factors such as stress or drowsiness, which result in quite high and quite low pressures, respectively. They may also derive from exogenous factors such as drugs or environmental influences. METHODS AND RESULTS: Impairment of the baroreflex may produce an unusually broad spectrum of clinical presentations; with acute baroreflex failure, a hypertensive crisis is the most common presentation. Over succeeding days to weeks, or in the absence of an acute event, volatile hypertension with periods of hypotension occurs and may continue for many years, usually with some attenuation of pressor surges and greater prominence of depressor valleys during long-term follow-up. With incomplete loss of baroreflex afferents, a mild syndrome of orthostatic tachycardia or orthostatic intolerance may appear. Finally, if the baroreflex failure occurs without concomitant destruction of the parasympathetic efferent vagal fibers, a resting state may lead to malignant vagotonia with severe bradycardia and hypotension and episodes of sinus arrest. CONCLUSIONS: Although baroreflex failure is not the most common cause of the above conditions, correct differentiation from other cardiovascular disorders is important, because therapy of baroreflex failure requires specific strategies, which may lead to successful control.

Geologic effects of hurricanes

NASA Astrophysics Data System (ADS)

Coch, Nicholas K.

1994-08-01

Hurricanes are intense low pressure systems of tropical origin. Hurricane damage results from storm surge, wind, and inland flooding from heavy rainfall. Field observations and remote sensing of recent major hurricanes such as Hugo (1989), Andrew (1992) and Iniki (1992) are providing new insights into the mechanisms producing damage in these major storms. Velocities associated with hurricanes include the counterclockwise vortex winds flowing around the eye and the much slower regional winds that steer hurricane and move it forward. Vectorial addition of theseof these two winds on the higher effective wind speed than on the left side. Coast-parallel hurricane tracks keep the weaker left side of the storm against the coast, whereas coast-normal tracks produce a wide swath of destruction as the more powerful right side of the storm cuts a swath of destruction hundreds of kilometers inland. Storm surge is a function of the wind speed, central pressure, shelf slope, shoreline configuration, and anthropogenic alterations to the shoreline. Maximum surge heights are not under the eye of the hurricane, where the pressure is lowest, but on the right side of the eye at the radius of maximum winds, where the winds are strongest. Flood surge occurs as the hurricane approaches land and drives coastal waters, and superimposed waves, across the shore. Ebb surge occurs when impounded surface water flows seaward as the storm moves inland. Flood and ebb surge damage have been greatly increased in recent hurricanes as a result of anthropogenic changes along the shoreline. Hurricane wind damage occurs on three scales — megascale, mesoscale and microscale. Local wind damage is a function of wind speed, exposure and structural resistance to velocity pressure, wind drag and flying debris. Localized extreme damage is caused by gusts that can locally exceed sustained winds by a factor of two in areas where there is strong convective activity. Geologic changes occuring in hurricanes include beach erosion, dune erosion, inlet formation from flood and ebb surge, landscape changes through tree destruction by wind and nearshore channeling and sedimentation resulting from ebb surge. Multi-decadal wet and dry cycles in West Africa seem to be associated with increases (wet periods) and decreases (dry periods) in the frequency of Atlantic Coast landfalling hurricanes. Coastalzone population and development has increased markedly in a time of low hurricane frequency in the 24 year dry cycle from1970 to the present. However, no previous climatic cycle in this century has exceeded 26 years. We may entering a multi-decadal cycle of greater hurricane activity, placing these highly urbanized shorelines in considerable danger.

The relationship between a blunted morning surge and a reversed nocturnal blood pressure dipping or "riser" pattern.

PubMed

Fujiwara, Takeshi; Tomitani, Naoko; Sato, Keiko; Okura, Ayako; Suzuki, Noriyuki; Kario, Kazuomi

2017-11-01

The authors sought to determine the association between the blunted morning blood pressure (BP) surge and nocturnal BP dipping of the "riser" pattern in 501 patients with hypertension enrolled in the ACHIEVE-ONE (Ambulatory Blood Pressure Control and Home Blood Pressure [Morning and Evening] Lowering by the N-Channel Blocker Cilnidipine) trial. The patients' sleep-trough morning BP surge and prewaking surge were calculated and then classified according to their nocturnal systolic BP reduction pattern as extreme dippers, dippers, nondippers, and risers. The prevalence of the riser pattern was significantly higher in both the lowest sleep-trough morning BP surge decile and the prewaking surge decile (blunted surge group) compared with the remaining deciles (56.0% vs 10.4% [P<.0001] and 59.2% vs 10.2% [P<.0001], respectively). The riser pattern was a significant determinant of both blunted sleep-trough morning BP surge (odds ratio, 73.3; P<.0001) and blunted prewaking surge (odds ratio, 14.8; P<.0001). The high prevalence of the riser pattern in patients with blunted morning BP surges may account for the cardiovascular risk previously reported in such patients. ©2017 Wiley Periodicals, Inc.

Study of storm surge trends in typhoon-prone coastal areas based on observations and surge-wave coupled simulations

NASA Astrophysics Data System (ADS)

Feng, Xingru; Li, Mingjie; Yin, Baoshu; Yang, Dezhou; Yang, Hongwei

2018-06-01

This is a study of the storm surge trends in some of the typhoon-prone coastal areas of China. An unstructured-grid, storm surge-wave-tide coupled model was established for the coastal areas of Zhejiang, Fujian and Guangdong provinces. The coupled model has a high resolution in coastal areas, and the simulated results compared well with the in situ observations and satellite altimeter data. The typhoon-induced storm surges along the coast of the study areas were simulated based on the established coupled model for the past 20 years (1997-2016). The simulated results were used to analyze the trends of the storm surges in the study area. The extreme storm surge trends along the central coast of Fujian Province reached up to 0.06 m/y, significant at the 90% confidence level. The duration of the storm surges greater than 1.0 and 0.7 m had an increasing trend along the coastal area of northern Fujian Province, significant at confidence levels of 70%-91%. The simulated trends of the extreme storm surges were also validated by observations from two tide gauge stations. Further studies show that the correlation coefficient (RTE) between the duration of the storm surge greater than 1 m and the annual ENSO index can reach as high as 0.62, significant at the 99% confidence level. This occurred in a location where the storm surge trend was not significant. For the areas with significant increasing storm surge trends, RTE was small and not significant. This study identified the storm surge trends for the full complex coastline of the study area. These results are useful both for coastal management by the government and for coastal engineering design.

Tide-surge interaction along the east coast of the Leizhou Peninsula, South China Sea

NASA Astrophysics Data System (ADS)

Zhang, Heng; Cheng, Weicong; Qiu, Xixi; Feng, Xiangbo; Gong, Wenping

2017-06-01

A triply-nested two-dimensional (2D) ocean circulation model along with observed sea level records are used to study tide-surge interaction along the east coast of the Leizhou Peninsula (LP) which is characterized by extensive mudflats, large tidal ranges and a complex coastline. The dependency of surge maxima on the water level and the phase of tide are respectively investigated using two statistical approaches. Results show that tide-surge interaction along the east coast of the LP is significant, where surges peak 3-6 h before or after the nearest high water. The triply-nested 2D ocean circulation model is used to quantify tide-surge interaction in this region and to investigate its physical cause. The largest amplitudes of tide-surge interaction are found in the shallow water region of the Leizhou Bay, with values up to 1 m during typhoon events. Numerical experiments reveal that nonlinear bottom friction is the main contributor to tide-surge interaction, while the contribution of the nonlinear advective effect can be neglected. The shallow water effect enhances the role of nonlinear bottom friction in determining tide-surge modulation, leaving the surge peaks usually occur on the rising or falling tide. It is also found that the relative contribution of local wind and remote wind is different depending on the storm track and storm intensity, which would finally affect the temporal and spatial distribution of tide-surge interaction during typhoon events. These findings confirm the importance of coupling storm surges and tides for the prediction of storm surge events in regions which are characterized by shallow water depths and large tidal ranges.

Molecular Genetic Studies of Bone Mechanical Strain and of Pedigrees With Very High Bone Density

DTIC Science & Technology

2008-11-01

J Cell Biol 1993, 62(2):352-361. 19. Petersen W, Rafii M: Immunolocalization of the angiogenetic factor pleiotrophin (PTN) in the growth plate of mice...361. 13. Petersen W, Rafii M: Immunolocalization of the angiogenetic factor pleiotrophin (PTN) in the growth plate of mice. Arch Orthop Trauma Surg

The eSurge-Venice project: how satellite data can improve the storm surge forecasting in the northern Adriatic Sea

NASA Astrophysics Data System (ADS)

Zecchetto, Stefano; Vignudelli, Stefano; Donlon, Craig; De Biasio, Francesco; Della Valle, Antonio; Umgiesser, Georg; Bajo, Marco

The Data User Element (DUE) program of the European Space Agency (ESA) is funding two projects (eSurge and eSurge-Venice) aimed to demonstrate the improvement of the storm surge forecasting through the use of Earth Observation (EO) data. eSurge-Venice (http://www.esurge-venice.eu/), is specifically focused on the Gulf of Venice, northern Adriatic Sea. The project objectives are: a) Select a number of Storm Surge Events occurred in the Venice lagoon since 1999; b) Provide the available satellite EO data related to the Storm Surge Events, mainly satellite winds and altimeter data, as well as all the available in-situ data and model forecasts; c) Provide a demonstration Near Real Time service (eSurge-Venice live) of EO data products and services in support of operational and experimental forecasting and warning services; d) Run a number of re-analysis cases, both for historical and contemporary storm surge events, to demonstrate the usefulness of EO data. Present storm surge models use atmospheric model wind fields as forcing. These are know to underestimate the wind in small basins like the Adriatic Sea (~1000 km by 300 km), where the orography plays an important role in shaping the winds. Therefore there is the need to verify and tune the atmospheric model wind fields used in the storm surge modeling, an activity which can easily done using satellite scatterometer winds. The project is now in the middle of his life, and promising preliminary results have been achieved using satellite scatterometer wind data to forge the atmospheric model wind fields forcing the storm surge model. This contribution will present the methodology adopted to tune the model wind fields according to the bias with scatterometer winds and the improvements induced in the storm surge model hindcast.

Objective measurement of postocclusion surge during phacoemulsification in human eye-bank eyes.

PubMed

Georgescu, Dan; Payne, Marielle; Olson, Randall J

2007-03-01

To objectively compare the postocclusion vacuum surge among different phacoemulsification machines and devices. Experimental study. Infiniti, Legacy, Millennium, and Sovereign were tested in an eye-bank eye. All the machines were tested with 20-gauge non-ABS tips, 430 mm Hg vacuum pressure, 24 ml/minute aspiration rate, peristaltic pump, and 75 cm bottle height. In addition, Infiniti and Legacy were also tested with 20-gauge bypass tips (ABS), 125 cm bottle height, and 40 ml/minute flow rate. We also tested 19-gauge tips with Infiniti and Sovereign and the venturi pump for Millennium. Significant differences were found between all the machines tested with Millennium peristaltic generating the least and Millennium Venturi the most surge. ABS tips significantly decreased the surge for Legacy but not for Infiniti. Cruise Control (CC) had a significant effect on Sovereign but not on Millennium. Increasing the bottle height decreased surge while increasing the flow increased surge for both Infiniti and Legacy. The 19-gauge tips increased surge for both Infiniti and Sovereign. Surge varied over a range of 40 microm to more than 2 mm. ABS and CC decrease surge, especially when the machine is not functioning near the limits of surge prevention. Certain parameters, such as a 19-gauge tip and high flow, dramatically increased surge, whereas elevating the bottle ameliorates it. Understanding the impact of all these features will help in minimizing the problem.

Isoflurane reduces the ischemia reperfusion injury surge: a longitudinal study with MRI.

PubMed

Taheri, Saeid; Shunmugavel, Anandakumar; Clark, Danielle; Shi, Honglian

2014-10-24

Recent studies show neuroprotective benefits of isoflurane (ISO) administered during cerebral ischemia. However, the available studies evaluated cerebral injury only at a single time point following the intervention and thus the longitudinal effect of ISO on ischemic tissues remains to be investigated. The objective of the present study was to investigate the longitudinal effect of ISO treatment in counteracting the deleterious effect of ischemia by evoking the transcription factor, hypoxia inducible factor-1 (HIF-1), and vascular endothelial growth factor (VEGF). Focal cerebral ischemia was induced in 70 rats by filament medial cerebral artery occlusion (MCAo) method. MCAo rats were randomly assigned to control (90 min ischemia) and MCAo+ISO (90 min ischemia+2% ISO) groups. Infarct volume, edema, intracerebral hemorrhage (ICH), and regional cerebral blood flow (rCBF) were measured in eight in vivo sequential MR imaging sessions for 3 weeks. Western blot analysis and immunofluorescence were used to determine the expression level of HIF-1α (the regulatable subunit of HIF-1) and VEGF proteins. ISO inhalation during ischemia significantly decreased the surge of infarct volume, edema, ICH, and reduced the mortality rate (p<0.01). ISO transiently altered the rCBF, significantly enhanced the expression of HIF-1α and VEGF, and decreased the immune cell infiltration. Locomotor dysfunction was ameliorated at a significantly faster pace, and the benefit was seen to persist up to three weeks. Treatment with ISO during ischemia limits the deadly surge in the dynamics of ischemia reperfusion injury with no observed long-term inverse effect. Copyright © 2014 Elsevier B.V. All rights reserved.

A review of tropical cyclone-generated storm surges: Global data sources, observations, and impacts

NASA Astrophysics Data System (ADS)

Needham, Hal F.; Keim, Barry D.; Sathiaraj, David

2015-06-01

Tropical cyclone-generated storm surges are among the world's most deadly and destructive natural hazards. This paper provides the first comprehensive global review of tropical storm surge data sources, observations, and impacts while archiving data in SURGEDAT, a global database. Available literature has provided data for more than 700 surge events since 1880, the majority of which are found in the western North Atlantic (WNA), followed by Australia/Oceania, the western North Pacific (WNP), and the northern Indian Ocean (NIO). The Bay of Bengal (BOB) in the NIO consistently observes the world's highest surges, as this subbasin averages five surges ≥5 m per decade and has observed credible storm tide levels reaching 13.7 m. The WNP observes the highest rate of low-magnitude surges, as the coast of China averages 54 surges ≥1 m per decade, and rates are likely higher in the Philippines. The U.S. Gulf Coast observes the second highest frequency of both high-magnitude (≥5 m) and low-magnitude (≥1 m) surges. The BOB observes the most catastrophic surge impacts, as 59% of global tropical cyclones that have killed at least 5000 people occurred in this basin. The six deadliest cyclones in this region have each killed at least 140,000 people, and two events have killed 300,000. Storm surge impacts transportation, agriculture, and energy sectors in the WNA. Oceania experiences long-term impacts, including contamination of fresh water and loss of food supplies, although the highest surges in this region are lower than most other basins.

14 CFR 33.73 - Power or thrust response.

Code of Federal Regulations, 2010 CFR

2010-01-01

....73 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: AIRCRAFT ENGINES Design and Construction; Turbine Aircraft Engines § 33.73 Power or... aircraft, without overtemperature, surge, stall, or other detrimental factors occurring to the engine...

14 CFR 33.73 - Power or thrust response.

Code of Federal Regulations, 2011 CFR

2011-01-01

....73 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: AIRCRAFT ENGINES Design and Construction; Turbine Aircraft Engines § 33.73 Power or... aircraft, without overtemperature, surge, stall, or other detrimental factors occurring to the engine...

Nonlinear terms in storm surge predictions: Effect of tide and shelf geometry with case study from Hurricane Rita

NASA Astrophysics Data System (ADS)

Rego, JoãO. L.; Li, Chunyan

2010-06-01

This study applied the finite volume coastal ocean model (FVCOM) to the storm surge induced by Hurricane Rita along the Louisiana-Texas coast. The model was calibrated for tides and validated with observed water levels. Peak water levels were shown to be lower than expected for a landfall at high tide. For low- and high-tide landfalls, nonlinear effects due to tide-surge coupling were constructive and destructive to total storm tide, respectively, and their magnitude reached up to 70% of the tidal amplitude in the Rita application. Tide-surge interaction was further examined using a standard hurricane under idealized scenarios to evaluate the effects of various shelf geometries, tides, and landfall timings (relative to tide). Nonlinearity was important between landfall position and locations within 2.5 × radius of maximum winds. On an idealized wide continental shelf, nonlinear effects reached up to 80% of the tidal amplitude with an S2 tide and up to 47% with a K1 tide. Increasing average depths by 4 m reduced nonlinear effects to 41% of the tidal amplitude; increasing the slope by a factor of 3 produced nonlinearities of just 26% of tide (both with a K1 tide). The nonlinear effect was greatest for landfalls at low tide, followed by landfalls at high tide and then by landfalls at midebb or midflood.

Storm surges formation in the White and Barents Seas

NASA Astrophysics Data System (ADS)

Arkhipkin, Victor; Dobrolyubov, Sergey; Korablina, Anastasia; Myslenkov, Stanislav

2016-04-01

Investigation of storm surges in the Arctic seas are of high priority in Russia due to the active development of offshore oil and gas, construction of facilities in the coastal zone, as well as for the safety of navigation. It is important to study the variability of surges, to predict this phenomena and subsequent economic losses, thus including such information into the Russian Arctic Development Program 2020. Surges in the White and Barents Seas are caused mainly by deep cyclones of two types: "diving" from the north (88% of all cyclones) and western. The average height of the storm surges in the White Sea is 0.6-0.9 m. An average duration of storm surges is about 80 hours. Mathematical modeling is used to analyze the characteristics of storm surges formation in the Dvina Bay of the White Sea, and in the Varandey village on the Barents Sea coast. Calculating storm surge heights in the White and Barents seas is performed using the ADCIRC model on an unstructured grid with a step from 20 km in the Barents Sea to 100 m in the White Sea. Unstructured grids allowed keeping small features of the coastline of the White and Barents seas, small islands and shallow banks, and assessing their impact on the development and transformation of wind-generated waves. The ADCIRC model used data of wind field reanalysis CFSv2. The storm surges were simulated for the time period from 1979 to 2010 and included scenarios with / without direct atmospheric pressure forcing, waves and tides. Numerical experiments have revealed distribution of storm surges in channels of the Northern Dvina River delta. The storm surges spreads in the model from the north-north-west of the Dvina Bay. As storm surge moves from the wellhead to the seaside estuary of the Northern Dvina (district Solombala), its height increases from 0.5 to 2 m. We also found a non-linear interaction of the surge and tide during the phase of surge destruction. This phenomenon is the highest in the period of low water, and the smallest in the period full of water. Analysis of storm surges in the Varandey village (the southern part of the Barents Sea) showed that the maximum height of storm surge reached 2.9 m in this region in July, 2010. The work performed was supported by the RSCF (grant № 14-37-00038)

Underwater and Dive Station Work-Site Noise Surveys

DTIC Science & Technology

2008-03-14

A) octave band noise measurements, dB (A) correction factors, dB ( A ) levels , MK-21 diving helmet attenuation correction factors, overall in-helmet...band noise measurements, dB (A) correction factors, dB ( A ) levels , MK-21 diving helmet attenuation correction factors, overall in-helmet dB (A...noise measurements, dB (A) correction factors, dB ( A ) levels , MK-21 diving helmet attenuation correction factors, overall in-helmet dB (A) level, and

Monitoring Hurricane Rita Inland Storm Surge: Chapter 7J in Science and the storms-the USGS response to the hurricanes of 2005

USGS Publications Warehouse

McGee, Benton D.; Tollett, Roland W.; Goree, Burl B.

2007-01-01

Pressure transducers (sensors) are accurate, reliable, and cost-effective tools to measure and record the magnitude, extent, and timing of hurricane storm surge. Sensors record storm-surge peaks more accurately and reliably than do high-water marks. Data collected by sensors may be used in storm-surge models to estimate when, where, and to what degree stormsurge flooding will occur during future storm-surge events and to calibrate and verify stormsurge models, resulting in a better understanding of the dynamics of storm surge.

Effect of hurricane paths on storm surge response at Tianjin, China

NASA Astrophysics Data System (ADS)

Feng, Xingru; Yin, Baoshu; Yang, Dezhou

2012-06-01

A hurricane induced storm surge simulation system was developed for Tianjin coast, which consists of a hurricane model and a storm surge model. The peak storm surge result of the simulation agreed well with that of the observation. Three observed paths (Rita, Mimie and WINNIE) and a hypothetical path (Rita2) were chosen as the selective hurricane paths according to their positions relative to Tianjin. The sensitivity of Tianjin storm surge to the four paths was investigated using the validated storm surge simulation system. Three groups of experiments were done. In group one, the models were forced by the wind field and air pressure; in group two and three the models were forced by the wind only and the air pressure only respectively. In the experiments, the hurricane moved with a fixed speed and an intensity of 50 year return period. The simulation results show that path of the type Rita2 is the easiest to cause storm surge disaster in Tianjin, and the effect of air pressure forcing is most evident for path of the type Rita in Tianjin storm surge process. The above conclusions were analyzed through the evolution of the wind fields and the air pressure distributions. Comparing the experiment results of Group one, two and three, it can be seen that the storm surge is mainly induced by the wind forcing and the nonlinear interaction between the effect of wind forcing and air pressure forcing on the storm surge tends to weaken the storm surge.

Hα Surges Initiated by Newly-emerging Satellite Magnetic Fields

NASA Astrophysics Data System (ADS)

Wang, Jun-feng; Zhou, Tuan-hui; Ji, Hai-sheng

2014-01-01

On July 22, 2011 and in the active region NOAA 11259 there ap- peared the event of the ejection of solar atmospheric Hα surges. According to the full-disc Hα observations of the Big Bear Solar Observatory in United States, three consecutive surges at one and the same place in the north of the main spot of the active region were discovered. The trajectories of these three surges exhib- ited the figure of straight lines, and their integral configuration is like an inverted Eiffel Tower. The first two surges are quite similar, and in each of them there appeared two bright points in the northern part of the main spot. After several minutes, the surges appeared in the midst of bright points. When the bright- ness of the bright points attained the maximum value, the surges spouted out from the midst of bright points. And after reaching the maximum altitude, they quickly vanished. Before the ejection of the third surge took place, no bright points appeared. Besides, its maximal altitude is merely one half of that of the first two surges. Via a comparison with the SDO/HMI (Solar Dynamics Obser- vatory/Helioseismic and Magnetic Imager) data of radial magnetic fields, it is found that in more than one hour before the appearance of the first surge there emerged bipolar magnetic fields in the region of ejection. Besides, in several min- utes before the ejection of each Hα surge the magnetic fluxes of positive polarity diminished. Via our analysis it is found that there appeared reconnections be- tween the newly emerging satellite magnetic fields and the preexisting magnetic fields in the spot, and this caused the continuous ejections of Hα surges.

Comparison of two recent storm surge events based on results of field surveys

NASA Astrophysics Data System (ADS)

Nakamura, Ryota; Shibayama, Tomoya; Mikami, Takahito; Esteban, Miguel; Takagi, Hiroshi; Maell, Martin; Iwamoto, Takumu

2017-10-01

This paper compares two different types of storm surge disaster based on field surveys. Two cases: a severe storm surge flood with its height of over 5 m due to Typhoon Haiyan (2013) in Philippine, and inundation of storm surge around Nemuro city in Hokkaido of Japan with its maximum surge height of 2.8 m caused by extra-tropical cyclone are taken as examples. For the case of the Typhoon Haiyan, buildings located in coastal region were severely affected due to a rapidly increase in ocean surface. The non-engineering buildings were partially or completely destroyed due to their debris transported to an inner bay region. In fact, several previous reports indicated two unique features, bore-like wave and remarkably high speed currents. These characteristics of the storm surge may contribute to a wide-spread corruption for the buildings around the affected region. Furthermore, in the region where the surge height was nearly 3 m, the wooden houses were completely or partially destroyed. On the other hand, in Nemuro city, a degree of suffering in human and facility caused by the storm surge is minor. There was almost no partially destroyed residential houses even though the height of storm surge reached nearly 2.8 m. An observation in the tide station in Nemuro indicated that this was a usual type of storm surge, which showed a gradual increase of sea level height in several hours without possessing the unique characteristics like Typhoon Haiyan. As a result, not only the height of storm surge but also the robustness of the buildings and characteristics of storm surge, such as bore like wave and strong currents, determined the existent of devastation in coastal regions.

Brief communication: The Khurdopin glacier surge revisited - extreme flow velocities and formation of a dammed lake in 2017

NASA Astrophysics Data System (ADS)

Steiner, Jakob F.; Kraaijenbrink, Philip D. A.; Jiduc, Sergiu G.; Immerzeel, Walter W.

2018-01-01

Glacier surges occur regularly in the Karakoram, but the driving mechanisms, their frequency and its relation to a changing climate remain unclear. In this study, we use digital elevation models and Landsat imagery in combination with high-resolution imagery from the Planet satellite constellation to quantify surface elevation changes and flow velocities during a glacier surge of the Khurdopin Glacier in 2017. Results reveal that an accumulation of ice volume above a clearly defined steep section of the glacier tongue since the last surge in 1999 eventually led to a rapid surge in May 2017 peaking with velocities above 5000 m a-1, which were among the fastest rates globally for a mountain glacier. Our data reveal that velocities on the lower tongue increase steadily during a 4-year build-up phase prior to the actual surge only to then rapidly peak and decrease again within a few months, which confirms earlier observations with a higher frequency of available velocity data. The surge return period between the reported surges remains relatively constant at ca. 20 years. We show the potential of a combination of repeat Planet and ASTER imagery to (a) capture peak surge velocities that are easily missed by less frequent Landsat imagery, (b) observe surface changes that indicate potential drivers of a surge and (c) monitor hazards associated with a surge. At Khurdopin specifically, we observe that the surging glacier blocks the river in the valley and causes a lake to form, which may grow in subsequent years and could pose threats to downstream settlements and infrastructure in the case of a sudden breach.

Accidental introductions of natural enemies: causes and implications

USDA-ARS?s Scientific Manuscript database

Accidental introductions of natural enemies, including parasitoid and predatory groups, may exceed species introduced intentionally. Several factors favor this: a general surge in international trade; lack of surveillance for species that are not associated with live plants or animals; inability to ...

Swift snowmelt and floods (lahars) caused by great pyroclastic surge at Mount St Helens volcano, Washington, 18 May 1980

USGS Publications Warehouse

Waitt, R.B.

1989-01-01

The initial explosions at Mount St. Helens, Washington, on the moring of 18 May 1980 developed into a huge pyroclastic surge that generated catastrophic floods off the east and west flanks of the volcano. Near-source surge deposits on the east and west were lithic, sorted, lacking in accretionary lapilli and vesiculated ash, not plastered against upright obstacles, and hot enough to char wood - all attributes of dry pyroclastic surge. Material deposited at the surge base on steep slopes near the volcano transformed into high-concentration lithic pyroclastic flows whose deposits contain charred wood and other features indicating that these flows were hot and dry. Stratigraphy shows that even the tail of the surge had passed the east and west volcano flanks before the geomorphically distinct floods (lahars) arrived. This field evidence undermines hypotheses that the turbulent surge was itself wet and that its heavy components segregated out to transform directly into lahars. Nor is there evidence that meters-thick snow-slab avalanches intimately mixed with the surge to form the floods. The floods must have instead originated by swift snowmelt at the base of a hot and relatively dry turbulent surge. Impacting hot pyroclasts probably transferred downslope momentum to the snow surface and churned snow grains into the surge base. Melting snow and accumulating hot surge debris may have moved initially as thousands of small thin slushflows. As these flows removed the surface snow and pyroclasts, newly uncovered snow was partly melted by the turbulent surge base; this and accumulating hot surge debris in turn began flowing, a self-sustaining process feeding the initial flows. The flows thus grew swiftly over tens of seconds and united downslope into great slushy ejecta-laden sheetfloods. Gravity accelerated the floods to more than 100 km/h as they swept down and off the volcano flanks while the snow component melted to form great debris-rich floods (lahars) channeled into valleys. ?? 1989 Springer-Verlag.

Mechanisms that Amplify, Attenuate and Deviate Glacier Response to Climate Change in Central East Greenland. (Invited)

NASA Astrophysics Data System (ADS)

Jiskoot, H.

2013-12-01

A multidecadal review of glacier fluctuations and case-studies of glacier processes and environments in central East Greenland will be used to demonstrate Mechanisms that Amplify, Attenuate and Deviate glacier response to climate forcings (MAAD). The different spatial and temporal scales at which MAAD affect mass balance and ice flow may complicate interpretation and longterm extrapolation of glacier response to climate change. A framework of MAAD characterisation and best-practice for interpreting climate signals while taking into account MAAD will be proposed. Glaciers in the Watkins Bjerge, Geikie Plateau and Stauning Alps regions of central East Greenland (68°-72°N) contain about 50000 km2 of glacierized area peripheral to the Greenland Ice Sheet. Within the region, large north-south and coast-inland climatic gradients, as well as complicated topography and glacier dynamics, result in discrepant glacier behaviour. Average retreat rates have doubled from about 2 to 4 km2 a-1 between the late 20th and early 21st centuries. However, glaciers terminating along the Atlantic coast display two times the retreat, thinning, and acceleration rates compared to glaciers terminating in inland fjords or on land. Despite similar climatic forcing variable glacier behaviour is apparent: individual glacier length change ranges from +57 m a-1 to -428 m a-1, though most retreat -20 to -100 m a-1. Interacting dynamic, mass balance and glacio-morphological mechanisms can amplify, attenuate or deviate glacier response (MAAD) to climate change, thus complicating the climatological interpretation of glacier length, area, and thickness changes. East Greenland MAAD include a range of common positive and negative feedback mechanisms in surface mass balance and terminus and subglacial boundary conditions affecting ice flow, but also mechanisms that have longterm or delayed effects. Certain MAAD may affect glacier change interpretation on multiple timescales: e.g. surging glaciers do not only pose problems for the direct interpretation of climate change from length and volume changes due to their dynamically-driven advance and retreat regimes, but also for the reconstruction of LIA extents from trimlines and moraines, and the reconstruction of surface mass balance due to crevasses, potholes or debris-cover. This presentation will address a range of MAAD, including thermal regime transitions; ocean influences on tidewater-terminating glaciers; glacier fragmentation and tributary-trunk interaction; glacier surging and tidewater behaviour; seasonal variations; glacier hypsometry and morphology; terrain and substrate; melt-albedo and melt-ice flow feedbacks; and ice marginal lakes.

Hurricane Katrina storm surge distribution and field observations on the Mississippi Barrier Islands

NASA Astrophysics Data System (ADS)

Fritz, Hermann M.; Blount, Chris; Sokoloski, Robert; Singleton, Justin; Fuggle, Andrew; McAdoo, Brian G.; Moore, Andrew; Grass, Chad; Tate, Banks

2007-08-01

Hurricane Katrina (23-30 August 2005) struck low-lying coastal plains particularly vulnerable to storm surge flooding. Maximum storm surges, overland flow depths, and inundation distances were measured along the Gulf Coast of Florida, Alabama, Mississippi and Louisiana. The vehicle based survey was complemented by inspections with the reconnaissance boat along the Gulf Coast and the Mississippi Barrier Islands. The storm surge peaked to the East of Katrina's path exceeding 10 meters in several locations along the Mississippi coastline. The storm surge measurements show that the lower floors of specially designed buildings were damaged by the surge of seawater and associated wave action, while the upper floors sustained minimal wind damage. Furthermore, the storm surge measurements along New Orleans's Lake shore indicate that the 17th Street Canal levee failed prior to overtopping. The land loss on the barrier islands resulted in an increased vulnerability of the US Gulf Coast to future hurricane storm surges.

Observing storm surges from space: Hurricane Igor off Newfoundland

PubMed Central

Han, Guoqi; Ma, Zhimin; Chen, Dake; deYoung, Brad; Chen, Nancy

2012-01-01

Coastal communities are becoming increasingly more vulnerable to storm surges under a changing climate. Tide gauges can be used to monitor alongshore variations of a storm surge, but not cross-shelf features. In this study we combine Jason-2 satellite measurements with tide-gauge data to study the storm surge caused by Hurricane Igor off Newfoundland. Satellite observations reveal a storm surge of 1 m in the early morning of September 22, 2010 (UTC) after the passage of the storm, consistent with the tide-gauge measurements. The post-storm sea level variations at St. John's and Argentia are associated with free equatorward-propagating continental shelf waves (with a phase speed of ~10 m/s and a cross-shelf decaying scale of ~100 km). The study clearly shows the utility of satellite altimetry in observing and understanding storm surges, complementing tide-gauge observations for the analysis of storm surge characteristics and for the validation and improvement of storm surge models. PMID:23259048

Efficacy of Cruise Control in controlling postocclusion surge with Legacy and Millennium venturi phacoemulsification machines.

PubMed

Wade, Matthew; Isom, Ryan; Georgescu, Dan; Olson, Randall J

2007-06-01

To determine the efficacy of the Cruise Control surge-limiting device (Staar Surgical) with phacoemulsification machines known to have high levels of surge. John A. Moran Eye Center Clinical Laboratories. In an in vitro study, postocclusion anterior chamber depth changes were measured in fresh phakic human eye-bank eyes using the Alcon Legacy and Bausch & Lomb Millennium venturi machines in conjunction with the Staar Cruise Control device. Both machines were tested with 19-gauge non-Aspiration Bypass System tips at high-surge settings (500 mm Hg vacuum pressure, 75 cm bottle height, 40 mL/min flow rate for the Legacy) and low-surge settings (400 mm Hg vacuum pressure, 125 cm bottle height, 40 mL/min flow rate for the Legacy). Adjusted parameters of flow, vacuum, and irrigation were used based on previous studies to create identical conditions for each device tested. The effect of the Cruise Control device on aspiration rates was also tested with both machines at the low-surge settings. At the high setting with the addition of Cruise Control, surge decreased significantly with the Legacy but was too large to measure with the Millennium venturi. At the low setting with the addition of Cruise Control, surge decreased significantly with both machines. Surge with the Millennium decreased from more than 1.0 mm to a mean of 0.21 mm +/- 0.02 (SD) (P<.0001). Surge with the Legacy decreased from a mean of 0.09 +/- 0.02 mm to 0.05 +/- 0 mm, a 42.9% decrease (P<.0001). The Millennium had the highest surge and aspiration rate before Cruise Control and the greatest percentage decrease in the surge and aspiration rates as a result of the addition of Cruise Control. In the Legacy machine, the Cruise Control device had a statistically and clinically significant effect. Cruise Control had a large effect on fluidics as well as surge amplitude with the Millennium machine. The greater the flow or greater the initial surge, the greater the impact of the Cruise Control device.

Storm Surge and Tide Interaction: A Complete Paradigm

NASA Astrophysics Data System (ADS)

Horsburgh, K.

2014-12-01

Estimates show that in 2005, in the largest 136 coastal cities, there were 40 million people and 3,000 billion of assets exposed to 1 in 100 year coastal flood events. Mean sea level rise will increase this exposure to 150 million people and 35,000 billion of assets by 2070. Any further change in the statistics of flood frequency or severity would impact severely on economic and social systems. It is therefore crucial to understand the physical drivers of extreme storm surges, and to have confidence in datasets used for extreme sea level statistics. Much previous research has focussed on the process of tide-surge interaction, and it is now widely accepted that the physical basis of tide-surge interaction is that a phase shift of the tidal signal represents the effect of the surge on the tide. The second aspect of interaction is that shallow water momentum considerations imply that differing tidal states should modulate surge generation: wind stress should have greater surge-generating potential on lower tides. We present results from a storm surge model of the European shelf that demonstrate that tidal range does have an effect on the surges generated. The cycle-integrated effects of wind stress (i.e. the skew surge) are greater when tidal range is low. Our results contradict the absence of any such correlation in tide gauge records. This suggests that whilst the modulating effect of the tide on the skew surge (the time-independent difference between peak prediction and observations) is significant, the difference between individual storms is dominant. This implies that forecasting systems must predict salient detail of the most intense storms. A further implication is that flood forecasting models need to simulate tides with acceptable accuracy at all coastal locations. We extend our model analysis to show that the same modulation of storm surges (by tidal conditions) applies to tropical cyclones. We conduct simulations using a mature operational storm surge model in the Bay of Bengal with tropical cyclones from the IBTrACs database; we demonstrate that - just as with the extra-tropical case - higher storm surges on the Bangladesh coastline are generated during smaller tides.

Development of Dimensionless Surge Response Functions for Hazard Assessment at Panama City, Florida

NASA Astrophysics Data System (ADS)

Taylor, N. R.; Irish, J. L.; Hagen, S. C.; Kaihatu, J. M.; McLaughlin, P. W.

2013-12-01

Reliable and robust methods of extreme value analysis in hurricane surge forecasting are of high importance in the coastal engineering profession. The Joint Probability Method (JPM) has become the preferred statistical method over the Historical Surge Population (HSP) method, due to its ability to give more accurate surge predictions, as demonstrated by Irish et. al in 2011 (J. Geophys. Res.). One disadvantage to this method is its high computational cost; a single location can require hundreds of simulated storms, each needing one thousand computational hours or more to complete. One way of overcoming this issue is to use an interpolating function, called a surge response function, to reduce the required number of simulations to a manageable number. These sampling methods, which use physical scaling laws, have been shown to significantly reduce the number of simulated storms needed for application of the JPM method. In 2008, Irish et. al. (J. Phys. Oceanogr.) demonstrated that hurricane surge scales primarily as a function of storm size and intensity. Additionally, Song et. al. in 2012 (Nat. Hazards) has shown that surge response functions incorporating bathymetric variations yield highly accurate surge estimates along the Texas coastline. This study applies the Song. et. al. model to 73 stations along the open coast, and 273 stations within the bays, in Panama City, Florida. The model performs well for the open coast and bay areas; surge levels at most stations along the open coast were predicted with RMS errors below 0.40 meters, and R2 values at or above 0.80. The R2 values for surge response functions within bays were consistently at or above 0.75. Surge levels at most stations within the North Bay and East Bay were predicted with RMS errors below 0.40 meters; within the West Bay, surge was predicted with RMS errors below 0.52 meters. Accurately interpolating surge values along the Panama City coast and bays enables efficient use of the JPM model in order to develop reliable probabilistic surge estimates for use in planning and design for hurricane mitigation.

Losses Assessment of Crops due to Typhoon Disaster in China Coastal Areas —— A Case Study of Zhanjiang City, Guangdong Province

NASA Astrophysics Data System (ADS)

Mo, W.; Fang, W.

2015-12-01

Vulnerability which quantifies the loss ratio under different hazard intensity is an important feature of the natural disaster system and has important significance to natural disaster risk assessment. Agriculture is an outdoor industry with high risk of meteorological disasters. The strong winds, heavy rain and storm surge are main typhoon hazard factors to crops. To provide a quantitative research method for the loss evaluation of crops due to typhoon disaster we first revised two vulnerability curves for crops under comprehensive intensity of typhoon based on the simulated hazard data and loss data related to historical typhoon events landing on China from 1949 to 2014；and then established a storm surge vulnerability matrix of crops regarding Zhanjiang City of Guangdong Province as the study area ; finally, we put forward three storm surge fragility curves for crops representing different states of loss. The results can effectively describe the typhoon vulnerability for crops in China coastal areas so as to provide the input to post-disaster loss assessments and catastrophe modeling applications.

Conductive surge testing of circuits and systems

NASA Technical Reports Server (NTRS)

Richman, P.

1980-01-01

Techniques are given for conductive surge testing of powered electronic equipment. The correct definitions of common and normal mode are presented. Testing requires not only spike-surge generators with a suitable range of open-circuit voltage and short-circuit current waveshapes, but also appropriate means, termed couplers, for connecting test surges to the equipment under test. Key among coupler design considerations is minimization of fail positives resulting from reduction in delivered surge energy due to the coupler. Back-filters and the lines on which they are necessary, are considered as well as ground-fault and ground potential rise. A method for monitoring delivered and resulting surge waves is mentioned.

Compressor surge counter

DOEpatents

Castleberry, Kimberly N.

1983-01-01

A surge counter for a rotating compressor is provided which detects surging by monitoring the vibration signal from an accelerometer mounted on the shaft bearing of the compressor. The circuit detects a rapid increase in the amplitude envelope of the vibration signal, e.g., 4 dB or greater in less than one second, which is associated with a surge onset and increments a counter. The circuit is rendered non-responsive for a period of about 5 seconds following the detection which corresponds to the duration of the surge condition. This prevents multiple registration of counts during the surge period due to rapid swings in vibration amplitude during the period.

Application of short-data methods on extreme surge levels

NASA Astrophysics Data System (ADS)

Feng, X.

2014-12-01

Tropical cyclone-induced storm surges are among the most destructive natural hazards that impact the United States. Unfortunately for academic research, the available time series for extreme surge analysis are very short. The limited data introduces uncertainty and affects the accuracy of statistical analyses of extreme surge levels. This study deals with techniques applicable to data sets less than 20 years, including simulation modelling and methods based on the parameters of the parent distribution. The verified water levels from water gauges spread along the Southwest and Southeast Florida Coast, as well as the Florida Keys, are used in this study. Methods to calculate extreme storm surges are described and reviewed, including 'classical' methods based on the generalized extreme value (GEV) distribution and the generalized Pareto distribution (GPD), and approaches designed specifically to deal with short data sets. Incorporating global-warming influence, the statistical analysis reveals enhanced extreme surge magnitudes and frequencies during warm years, while reduced levels of extreme surge activity are observed in the same study domain during cold years. Furthermore, a non-stationary GEV distribution is applied to predict the extreme surge levels with warming sea surface temperatures. The non-stationary GEV distribution indicates that with 1 Celsius degree warming in sea surface temperature from the baseline climate, the 100-year return surge level in Southwest and Southeast Florida will increase by up to 40 centimeters. The considered statistical approaches for extreme surge estimation based on short data sets will be valuable to coastal stakeholders, including urban planners, emergency managers, and the hurricane and storm surge forecasting and warning system.

Environmental assessments on schools located on or near former industrial facilities: Feedback on attenuation factors for the prediction of indoor air quality.

PubMed

Derycke, Virginie; Coftier, Aline; Zornig, Clément; Léprond, Hubert; Scamps, Mathilde; Gilbert, Dominique

2018-06-01

One of the goals of the French national campaign called "Etablissements Sensibles (Sensitive Establishments)" is to evaluate indoor air degradation in schools because of vapor intrusion of volatile compounds from soil gases towards the indoor air, related to the presence of former industrial sites on or near the establishment. During this campaign, as recommended by the United States of Environmental Protection Agency (US EPA), indoor air quality was evaluated from soil gas concentrations using generic attenuation factors, and extra investigations into soil gases and indoor air were performed when the estimated values exceeded target indoor air concentrations. This study exploits matched data on subsurface soil gases and indoor air that came from the "Sensitive Establishments" campaign. It aims to consolidate and refine the use of attenuation factors as a function of environmental variables acquired routinely during environmental assessments. We have been able to select the measured environmental variables that have the most influence on vapor intrusion using Principal Components Analysis and hypotheses tests. Since the collected data are mainly related to weak sources (only 15% schools required risk management measures related to vapor intrusion), halogenated volatile organic compounds (HVOC) were selected as tracer compounds for vapor intrusion for this study. This choice enables the exclusion or minimization of background sources contributions. From the results we have calculated the descriptive statistics of the attenuation factors distribution for the subslab-to-indoor air pathway and refined the attenuation factors for this pathway through an easily obtained parameter, building age. Qualitative comparison of attenuation factors according to the building age shows that attenuation factors observed for building less than 50 years are lower than attenuation factors for buildings 50 years old and above. These results show the utility of creating databases for consolidating and refining attenuation factors and therefore improving their use. Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.

Risk Assessment of Hurricane Storm Surge for Tampa Bay

NASA Astrophysics Data System (ADS)

Lin, N.; Emanuel, K.

2011-12-01

Hurricane storm surge presents a major hazard for the United States and many other coastal areas around the world. Risk assessment of current and future hurricane storm surge provides the basis for risk mitigation and related decision making. This study investigates the hurricane surge risk for Tampa Bay, located on the central west coast of Florida. Although fewer storms have made landfall in the central west Florida than in regions farther west in the Gulf of Mexico and the east coast of U.S., Tampa Bay is highly vulnerable to storm surge due to its geophysical features. It is surrounded by low-lying lands, much of which may be inundated by a storm tide of 6 m. Also, edge waves trapped on the west Florida shelf can propagate along the coastline and affect the sea level outside the area of a forced storm surge; Tampa Bay may be affected by storms traversing some distance outside the Bay. Moreover, when the propagation speed of the edge wave is close to that of a storm moving parallel to the coast, resonance may occur and the water elevation in the Bay may be greatly enhanced. Therefore, Tampa Bay is vulnerable to storms with a broad spectrum of characteristics. We apply a model-based risk assessment method to carry out the investigation. To estimate the current surge risk, we apply a statistical/deterministic hurricane model to generate a set of 1500 storms for the Tampa area, under the observed current climate (represented by 1981-2000 statistics) estimated from the NCAR/NCEP reanalysis. To study the effect of climate change, we use four climate models, CNRM-CM3, ECHAM, GFDL-CM2.0, and MIROC3.2, respectively, to drive the hurricane model to generate four sets of 1500 Tampa storms under current climate conditions (represented by 1981-2000 statistics) and another four under future climate conditions of the IPCC-AR4 A1B emission scenario (represented by 2081-2100 statistics). Then, we apply two hydrodynamic models, the Advanced Circulation (ADCIRC) model and the Sea, Lake, and Overland Surges from Hurricanes (SLOSH) model with grids of various resolutions to simulate the surges induced by the synthetic storms. The surge risk under each of the climate scenarios is depicted by a surge return level curve (exceedance probability curve). For the city of Tampa, the heights of the 100-year, 500-year, and 1000-year surges under the current climate are estimated to be 3.85, 5.66, and 6.31 m, respectively. Two of the four climate models predict that surge return periods will be significantly shortened in the future climates due to the change of storm climatology; the current 100-year surge may happen every 50 years or less, the 500-year surge every 200 years or less, and the 1000-year surge every 300 years or less. The other two climate models predict that the surge return periods will become moderately shorter or remain almost unchanged in the future climates. Extreme surges up to 12 m at Tampa appear in our simulations. Although occurring with very small probabilities, these extreme surges would have a devastating impact on the Tampa Bay area. By examining the generated synthetic surge database, we study the characteristics of the extreme storms at Tampa Bay, especially for the storms that may interact with edge waves along the Florida west coast.

Increasing Flood Risk due to Run-off Outflow near Estuarine City during Storm Event

NASA Astrophysics Data System (ADS)

Son, S.; Lee, C.; Do, K.; Jung, T.

2017-12-01

Tropical cyclone easily causes inundation damage to low-lying coastal area and the damage may be amplified due to tide motion, sea-level rise, riverine discharges. Specifically, typhoons are accompanied by intensive rainfall, which will of course raise the river water level and thus enhance the flooding damages. If the tidal cycle coincides the high water, flooding will be even aggravated. In the present study, we simulated storm surge motions at the coastal area considering combined effects of tidal and river discharge with aim to improve the accuracy of flooding prediction. The quasi 3-dimension ocean circulation model, Delf3D was used which solves the unsteady shallow water equation in the 2D and 3D. Since Delft3D is much applicable to accommodate the indirect flooding factors such as riverine discharge and short waves, outer-coupled modeling system was established to account for combined tide-surge-riverine discharge effects. In such integrated system, 11 tidal constituents were input as open boundary condition using TPXO 7.2 model, while the water level per unit time was preliminary calculated by HEC-HMS model and input as the upstream boundary conditions for river inside the domain. Typhoon MAEMI which attacked Masan city located at southern coast of South Korea and caused severe inundation damages in 2003 was selected for the study event. Basic information for typhoon such as path, wind speed, atmospheric pressure every 3 hours was provided by the Korea Meteorological Agency and was adopted. The simulation was implemented with tide and storm surge boundary conditions focusing on the target area, Masan, while the additional consideration on the discharge of the river inside the domain was also made. Simulated water level at the fixed location was compared to the observation for its verification and the extent of inundation areas of Masan were compared between observed and calculated. The marginal contribution of riverine discharge on the flooding area(or depth) was assessed by comparing tide-surge with tide-surge-riverine discharge simulations. Finally, the importance of the specific consideration on the riverine discharge during storm surge modeling can be addressed.

Nonlinear control of rotating stall and surge with axisymmetric bleed and air injection on axial flow compressors

NASA Astrophysics Data System (ADS)

Yeung, Chung-Hei (Simon)

The study of compressor instabilities in gas turbine engines has received much attention in recent years. In particular, rotating stall and surge are major causes of problems ranging from component stress and lifespan reduction to engine explosion. In this thesis, modeling and control of rotating stall and surge using bleed valve and air injection is studied and validated on a low speed, single stage, axial compressor at Caltech. Bleed valve control of stall is achieved only when the compressor characteristic is actuated, due to the fast growth rate of the stall cell compared to the rate limit of the valve. Furthermore, experimental results show that the actuator rate requirement for stall control is reduced by a factor of fourteen via compressor characteristic actuation. Analytical expressions based on low order models (2--3 states) and a high fidelity simulation (37 states) tool are developed to estimate the minimum rate requirement of a bleed valve for control of stall. A comparison of the tools to experiments show a good qualitative agreement, with increasing quantitative accuracy as the complexity of the underlying model increases. Air injection control of stall and surge is also investigated. Simultaneous control of stall and surge is achieved using axisymmetric air injection. Three cases with different injector back pressure are studied. Surge control via binary air injection is achieved in all three cases. Simultaneous stall and surge control is achieved for two of the cases, but is not achieved for the lowest authority case. This is consistent with previous results for control of stall with axisymmetric air injection without a plenum attached. Non-axisymmetric air injection control of stall and surge is also studied. Three existing control algorithms found in literature are modeled and analyzed. A three-state model is obtained for each algorithm. For two cases, conditions for linear stability and bifurcation criticality on control of rotating stall are derived and expressed in terms of implementation-oriented variables such as number of injectors. For the third case, bifurcation criticality conditions are not obtained due to complexity, though linear stability property is derived. A theoretical comparison between the three algorithms is made, via the use of low-order models, to investigate pros and cons of the algorithms in the context of operability. The effects of static distortion on the compressor facility at Caltech is characterized experimentally. Results consistent with literature are obtained. Simulations via a high fidelity model (34 states) are also performed and show good qualitative as well as quantitative agreement to experiments. A non-axisymmetric pulsed air injection controller for stall is shown to be robust to static distortion.

48 CFR 252.217-7001 - Surge option.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 48 Federal Acquisition Regulations System 3 2010-10-01 2010-10-01 false Surge option. 252.217-7001... Clauses 252.217-7001 Surge option. As prescribed in 217.208-70(b), use the following clause: Surge Option (AUG 1992) (a) General. The Government has the option to— (1) Increase the quantity of supplies or...

30 CFR 57.16002 - Bins, hoppers, silos, tanks, and surge piles.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Bins, hoppers, silos, tanks, and surge piles... NONMETAL MINES Materials Storage and Handling § 57.16002 Bins, hoppers, silos, tanks, and surge piles. (a) Bins, hoppers, silos, tanks, and surge piles, where loose unconsolidated materials are stored, handled...

30 CFR 56.16002 - Bins, hoppers, silos, tanks, and surge piles.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Bins, hoppers, silos, tanks, and surge piles... MINES Materials Storage and Handling § 56.16002 Bins, hoppers, silos, tanks, and surge piles. (a) Bins, hoppers, silos, tanks, and surge piles, where loose unconsolidated materials are stored, handled or...

Alternative Fuels Data Center: Idaho Surges Ahead with Electric Vehicle

Science.gov Websites

Charging Idaho Surges Ahead with Electric Vehicle Charging to someone by E-mail Share Alternative Fuels Data Center: Idaho Surges Ahead with Electric Vehicle Charging on Facebook Tweet about Alternative Fuels Data Center: Idaho Surges Ahead with Electric Vehicle Charging on Twitter Bookmark

Storm Surges. Teacher Guide and Activity Book. OEAGLS Investigation No. 25.

ERIC Educational Resources Information Center

Keir, John; Mayer, Victor J.

This investigation is designed to help students understand storm surges on Lake Erie. Activity A includes experiments and discussions intended to help students understand what causes storm surges on Lake Erie. Activity B considers how storm surges affect water levels and, in turn, coastal areas. The student booklet contains questions, experiments,…

Storm Surge Measurement with an Airborne Scanning Radar Altimeter

NASA Technical Reports Server (NTRS)

Wright, C. W.; Walsh, E. J.; Krabill, W. B.; Shaffer, W. A.; Baig, S. R.; Peng, M.; Pietrafesa, L. J.; Garcia, A. W.; Marks, F. D., Jr.; Black, P. G.;

The Development of Storm Surge Ensemble Prediction System and Case Study of Typhoon Meranti in 2016

NASA Astrophysics Data System (ADS)

Tsai, Y. L.; Wu, T. R.; Terng, C. T.; Chu, C. H.

2017-12-01

Taiwan is under the threat of storm surge and associated inundation, which is located at a potentially severe storm generation zone. The use of ensemble prediction can help forecasters to know the characteristic of storm surge under the uncertainty of track and intensity. In addition, it can help the deterministic forecasting. In this study, the kernel of ensemble prediction system is based on COMCOT-SURGE (COrnell Multi-grid COupled Tsunami Model - Storm Surge). COMCOT-SURGE solves nonlinear shallow water equations in Open Ocean and coastal regions with the nested-grid scheme and adopts wet-dry-cell treatment to calculate potential inundation area. In order to consider tide-surge interaction, the global TPXO 7.1 tide model provides the tidal boundary conditions. After a series of validations and case studies, COMCOT-SURGE has become an official operating system of Central Weather Bureau (CWB) in Taiwan. In this study, the strongest typhoon in 2016, Typhoon Meranti, is chosen as a case study. We adopt twenty ensemble members from CWB WRF Ensemble Prediction System (CWB WEPS), which differs from parameters of microphysics, boundary layer, cumulus, and surface. From box-and-whisker results, maximum observed storm surges were located in the interval of the first and third quartile at more than 70 % gauge locations, e.g. Toucheng, Chengkung, and Jiangjyun. In conclusion, the ensemble prediction can effectively help forecasters to predict storm surge especially under the uncertainty of storm track and intensity

Analysis of multiple positive feedback paradigms demonstrates a complete absence of LH surges and GnRH activation in mice lacking kisspeptin signaling.

PubMed

Dror, Tal; Franks, Jennifer; Kauffman, Alexander S

2013-06-01

Kisspeptin stimulates gonadotropin-releasing hormone (GnRH) neurons via the kisspeptin receptor, Kiss1r. In rodents, estrogen-responsive kisspeptin neurons in the rostral hypothalamus have been postulated to mediate estrogen-induced positive feedback induction of the preovulatory luteinizing hormone (LH) surge. However, conflicting evidence exists regarding the ability of mice lacking Kiss1r to display LH surges in response to exogenous hormones. Whether the discrepancy reflects different mouse strains used and/or utilization of different surge-induction paradigms is unknown. Here, we tested multiple hormonal paradigms in one Kiss1r knockout (KO) model to see which paradigms, if any, could generate circadian-timed LH surges. Kiss1r KO and wild-type (WT) females were ovariectomized, given sex steroids in various modes, and assessed several days later for LH levels in the morning or evening (when surges occur). Serum LH levels were very low in all morning animals, regardless of genotype or hormonal paradigm. In each paradigm, virtually all WT females displayed clear LH surges in the evening, whereas none of the KO females demonstrated LH surges. The lack of LH surges in KO mice reflects a lack of GnRH secretion rather than diminished pituitary responsiveness from a lifetime lack of GnRH exposure because KO mice responded to GnRH priming with robust LH secretion. Moreover, high cfos-GnRH coexpression was detected in WT females in the evening, whereas low cfos-GnRH coexpression was present in KO females at all time points. Our findings conclusively demonstrate that WT females consistently display LH surges under multiple hormonal paradigms, whereas Kiss1r KO mice do not, indicating that kisspeptin-Kiss1r signaling is mandatory for GnRH/LH surge induction.

Spatial distribution of erosion and deposition during a glacier surge: Brúarjökull, Iceland

NASA Astrophysics Data System (ADS)

Korsgaard, Niels J.; Schomacker, Anders; Benediktsson, Ívar Örn; Larsen, Nicolaj K.; Ingólfsson, Ólafur; Kjær, Kurt H.

2015-12-01

Time-series of digital elevation models (DEMs) of the forefield of the Brúarjökull surge-type glacier in Iceland were used to quantify the volume of material that was mobilized by the 1963-1964 surge. The DEMs were produced by stereophotogrammetry on aerial photographs from before the surge (1961) and after (1988 and 2003). The analysis was performed on two DEMs of Difference (DoDs), i.e., a 1961-2003 DoD documenting the impact of the surge and a 1988-2003 DoD documenting the post-surge modification of the juvenile surging glacier landsystem. Combined with a digital geomorphological map, the DoDs allow us to quantify the impact of the surge on a landsystem scale down to individual landforms. A total of 34.2 ± 11.3 × 106 m3 of material was mobilized in the 30.7-km2 study area as a result of the most recent surge event. Of these, 17.4 ± 6.6 × 106 m3 of the material were eroded and 16.8 ± 4.7 × 106 m3 were deposited. More than half of the deposited volume was ice-cored landforms. This study demonstrates that although the total mobilized mass volume is high, the net volume gain of ice and sediment deposited as landforms in the forefield caused by the surge is low. Furthermore, deposition of new dead-ice from the 1963-1964 surge constitutes as much as 64% of the volume gain in the forefield. The 1988-2003 DoD is used to quantify the melt-out of this dead-ice and other paraglacial modification of the recently deglaciated forefield of Brúarjökull.

Improvements of Storm Surge Modelling in the Gulf of Venice with Satellite Data: The ESA Due Esurge-Venice Project

NASA Astrophysics Data System (ADS)

De Biasio, F.; Bajo, M.; Vignudelli, S.; Papa, A.; della Valle, A.; Umgiesser, G.; Donlon, C.; Zecchetto, S.

2016-08-01

Among the most detrimental natural phenomena, storm surges heavily endanger the environment, the economy and the everyday life of sea-side countries and coastal zones. Considering that 120.000.000 people live in the Mediterranean area, with additional 200.000.000 presences in Summer for tourism purposes, the correct prediction of storm surges is crucial to avoid fatalities and economic losses. Earth Observation (EO) can play an important role in operational storm surge forecasting, yet it is not widely diffused in the storm surge community. In 2011 the European Space Agency (ESA), through its Data User Element (DUE) programme, financed two projects aimed at encouraging the uptake of EO data in this sector: eSurge and eSurge-Venice (eSV). The former was intended to address the issues of a wider users' community, while the latter was focused on a restricted geographical area: the northern Adriatic Sea and the Gulf of Venice. Among the objectives of the two projects there were a number of storm surge hindcast experiments using satellite data, to demonstrate the improvements on the surge forecast brought by EO. We report here the results of the hindcast experiments of the eSV project. They were aimed to test the sensitivity of a storm surge model to a forcing wind field modified with scatterometer data in order to reduce the bias between simulated and observed winds. Hindcast experiments were also performed to test the response of the storm surge model to the assimilation, with a dual 4D-Var system, of satellite altimetry observations as model errors of the initial state of the sea surface level. Remarkable improvements on the storm surge forecast have been obtained for what concerns the modified model wind forcing. Encouraging results have been obtained also in the assimilation experiments.

The “Ram Effect”: A “Non-Classical” Mechanism for Inducing LH Surges in Sheep

PubMed Central

Fabre-Nys, Claude; Chanvallon, Audrey; Dupont, Joëlle; Lardic, Lionel; Lomet, Didier; Martinet, Stéphanie; Scaramuzzi, Rex J.

2016-01-01

During spring sheep do not normally ovulate but exposure to a ram can induce ovulation. In some ewes an LH surge is induced immediately after exposure to a ram thus raising questions about the control of this precocious LH surge. Our first aim was to determine the plasma concentrations of oestradiol (E2) E2 in anoestrous ewes before and after the “ram effect” in ewes that had a “precocious” LH surge (starting within 6 hours), a “normal” surge (between 6 and 28h) and “late» surge (not detected by 56h). In another experiment we tested if a small increase in circulating E2 could induce an LH surge in anoestrus ewes. The concentration of E2 significantly was not different at the time of ram introduction among ewes with the three types of LH surge. “Precocious” LH surges were not preceded by a large increase in E2 unlike “normal” surges and small elevations of circulating E2 alone were unable to induce LH surges. These results show that the “precocious” LH surge was not the result of E2 positive feedback. Our second aim was to test if noradrenaline (NA) is involved in the LH response to the “ram effect”. Using double labelling for Fos and tyrosine hydroxylase (TH) we showed that exposure of anoestrous ewes to a ram induced a higher density of cells positive for both in the A1 nucleus and the Locus Coeruleus complex compared to unstimulated controls. Finally, the administration by retrodialysis into the preoptic area, of NA increased the proportion of ewes with an LH response to ram odor whereas treatment with the α1 antagonist Prazosin decreased the LH pulse frequency and amplitude induced by a sexually active ram. Collectively these results suggest that in anoestrous ewes NA is involved in ram-induced LH secretion as observed in other induced ovulators. PMID:27384667

Association of morning blood pressure surge with carotid intima-media thickness and cardiac dysfunction in patients with cardiac syndrome-X.

PubMed

Mahfouz, Ragab A; Goda, Mohammad; Galal, Islam; Ghareb, Mohamed S

2018-05-23

Background & hypothesis: We hypothesized that exaggerated morning blood pressure surge, may contribute in cardiac dysfunction and arterial stiffness in patients with cardiac syndrome X. Thus we investigated the impact of morning blood pressure surge on cardiac function and carotid intima-media thickness in subjects with cardiac syndrome X. We studied patients with cardiac syndrome X using ambulatory blood pressure monitoring and investigated the association of morning blood pressure surge with carotid intima thickness, left atrial volume index and left ventricular filling (E/e'). Seventy patients with cardiac syndrome X were enrolled for the study and compared with 70 age and sex matched controls. Patients with cardiac syndrome X were stratified based on the systolic morning blood pressure surge value of control subjects to patients with exaggerated blood pressure surge (n = 42) and those with normal morning blood pressure surge (n = 28). Basal heart rate (p < .05), high sensitive C-reactive protein (p < .01), left atrial volume index (p < .01), E/e' (p < .01); carotid intima-media thickness (p < .001) and percentage of detected plaque (p < .005) were significantly higher in patients with exaggerated morning blood pressure surge group than those with morning blood pressure surge group. Morning blood pressure surge was significantly correlated with carotid intima-media thickness, high sensitive C-reactive protein, left atrial volume index and E/e' ratio in patients with cardiac syndrome X. In multivariate analysis, exaggerated morning blood pressure surge was the only independent predictor of increased carotid intima-media thickness (OR = 2.379; p < .001), and diastolic dysfunction (OR = 2.464; p < .001) in patients with cardiac syndrome X. Our data suggest that excessive morning blood pressure surge is an independent predictor for arterial stiffness and diastolic dysfunction in patients with cardiac syndrome X.

Magnitude of Morning Surge in Blood Pressure Is Associated with Sympathetic but Not Cardiac Baroreflex Sensitivity

PubMed Central

Johnson, Aaron W.; Hissen, Sarah L.; Macefield, Vaughan G.; Brown, Rachael; Taylor, Chloe E.

2016-01-01

The ability of the arterial baroreflex to regulate blood pressure may influence the magnitude of the morning surge in blood pressure (MSBP). The aim was to investigate the relationships between sympathetic and cardiac baroreflex sensitivity (BRS) and the morning surge. Twenty-four hour ambulatory blood pressure was recorded in 14 young individuals. The morning surge was defined via the pre-awakening method, which is calculated as the difference between mean blood pressure values 2 h before and 2 h after rising from sleep. The mean systolic morning surge, diastolic morning surge, and morning surge in mean arterial pressures were 15 ± 2, 13 ± 1, and 11 ± 1 mmHg, respectively. During the laboratory protocol, continuous measurements of blood pressure, heart rate, and muscle sympathetic nerve activity (MSNA) were made over a 10-min period of rest. Sympathetic BRS was quantified by plotting MSNA burst incidence against diastolic pressure (sympathetic BRSinc), and by plotting total MSNA against diastolic pressure (sympathetic BRStotal). Cardiac BRS was quantified using the sequence method. The mean values for sympathetic BRSinc, sympathetic BRStotal and cardiac BRS were −1.26 ± 0.26 bursts/100 hb/mmHg, −1.60 ± 0.37 AU/beat/mmHg, and 13.1 ± 1.5 ms/mmHg respectively. Significant relationships were identified between sympathetic BRSinc and the diastolic morning surge (r = 0.62, p = 0.02) and the morning surge in mean arterial pressure (r = 0.57, p = 0.03). Low sympathetic BRS was associated with a larger morning surge in mean arterial and diastolic blood pressure. Trends for relationships were identified between sympathetic BRStotal and the diastolic morning surge (r = 0.52, p = 0.066) and the morning surge in mean arterial pressure (r = 0.48, p = 0.095) but these did not reach significance. There were no significant relationships between cardiac BRS and the morning surge. These findings indicate that the ability of the baroreflex to buffer increases in blood pressure via reflexive changes in MSNA may play a role in determining the magnitude of the MSBP. PMID:27660603

A Basis Function Approach to Simulate Storm Surge Events for Coastal Flood Risk Assessment

NASA Astrophysics Data System (ADS)

Wu, Wenyan; Westra, Seth; Leonard, Michael

2017-04-01

Storm surge is a significant contributor to flooding in coastal and estuarine regions, especially when it coincides with other flood producing mechanisms, such as extreme rainfall. Therefore, storm surge has always been a research focus in coastal flood risk assessment. Often numerical models have been developed to understand storm surge events for risk assessment (Kumagai et al. 2016; Li et al. 2016; Zhang et al. 2016) (Bastidas et al. 2016; Bilskie et al. 2016; Dalledonne and Mayerle 2016; Haigh et al. 2014; Kodaira et al. 2016; Lapetina and Sheng 2015), and assess how these events may change or evolve in the future (Izuru et al. 2015; Oey and Chou 2016). However, numeric models often require a lot of input information and difficulties arise when there are not sufficient data available (Madsen et al. 2015). Alternative, statistical methods have been used to forecast storm surge based on historical data (Hashemi et al. 2016; Kim et al. 2016) or to examine the long term trend in the change of storm surge events, especially under climate change (Balaguru et al. 2016; Oh et al. 2016; Rueda et al. 2016). In these studies, often the peak of surge events is used, which result in the loss of dynamic information within a tidal cycle or surge event (i.e. a time series of storm surge values). In this study, we propose an alternative basis function (BF) based approach to examine the different attributes (e.g. peak and durations) of storm surge events using historical data. Two simple two-parameter BFs were used: the exponential function and the triangular function. High quality hourly storm surge record from 15 tide gauges around Australia were examined. It was found that there are significantly location and seasonal variability in the peak and duration of storm surge events, which provides additional insights in coastal flood risk. In addition, the simple form of these BFs allows fast simulation of storm surge events and minimises the complexity of joint probability analysis for flood risk analysis considering multiple flood producing mechanisms. This is the first step in applying a Monte Carlo based joint probability method for flood risk assessment.

Storm surge and tide interaction: a complete paradigm

NASA Astrophysics Data System (ADS)

Horsburgh, Kevin; Williams, Jane; Proctor, Robert

2014-05-01

Globally, 200 million people live on coastal floodplains and about 1 trillion worth of assets lie within 1 metre of mean sea level. Any change in the statistics of flood frequency or severity would impact on economic and social systems. It is therefore crucial to understand the physical drivers of extreme storm surges, and to have confidence in datasets used for extreme sea level statistics. Much previous research has focussed on the process of tide-surge interaction, and it is now widely accepted that the physical basis of tide-surge interaction is that a phase shift of the tidal signal represents the effect of the surge on the tide. The second aspect of interaction is that shallow water momentum considerations imply that differing tidal states should modulate surge generation: wind stress should have greater surge-generating potential on lower tides. This has been shown previously by analytical models but not as yet confirmed by fully non-linear models of the continental shelf. We present results from an operational model of the European shelf that demonstrate that tidal range does have an effect on the surges generated. The cycle-integrated effects of wind stress (i.e. the skew surge) are generally greater when tidal range is low. Our results contradict the absence of any such correlation observed in the complete record of UK tide gauge data. This suggests that whilst the modulating effect of the tide on the skew surge (the time-independent difference between peak prediction and observations) is significant, the difference between individual storms is dominant. This implies that forecasting systems must predict salient detail of the most intense storms. A further implication is that operational models need to simulate tides with acceptable accuracy at all coastal locations. We extend our model analysis to show that the same modulation of storm surges (by tidal conditions) applies to tropical cyclones. We conduct simulations using a mature operational storm surge model in the Bay of Bengal with tropical cyclones from the IBTrACs database; we demonstrate that - just as with the extra-tropical case - higher storm surges on the Bangladesh coastline are generated during smaller tides.

Pineal melatonin and the innate immune response: the TNF-alpha increase after cesarean section suppresses nocturnal melatonin production.

PubMed

Pontes, Gerlândia N; Cardoso, Elaine C; Carneiro-Sampaio, Magda M S; Markus, Regina P

2007-11-01

The nocturnal surge of melatonin is the endocrine expression of the circadian system and is essential for organizing the timing of various endogenous processes. Previous works suggest that, in the beginning of a defense response, the increase in circulating tumor necrosis factor-alpha (TNF-alpha) leads to a transient block of nocturnal melatonin production and promotes a disruption of internal time organization. In the present paper, the concentration of melatonin and cytokines [TNF-alpha, interferon-gamma (IFN-gamma), interleukin (IL)-2, IL-4, IL-5, IL-10, IL-12] in the colostrum (postdelivery day 3) and in the milk (postdelivery days 10, 15, 20 and 30) obtained at midday and midnight from mothers who gave birth by vaginal or cesarean section were compared. The nocturnal melatonin surge observed 3 days after vaginal delivery was absent after cesarean section. IL-12 presented no daily variation in either case, while daily variations in IFN-gamma, IL-10, IL-4 and IL-5 were observed after vaginal delivery and cesarean section. On the other hand, the increase in TNF-alpha after cesarean section resulted in suppression of the nocturnal melatonin surge. Daily variation of IL-2 was only observed after recovery of the nocturnal melatonin surge, 30 days after cesarean section. The present paper supports the hypothesis of a cross-talk between the pineal gland and the immune system, which could represent a putative immune-pineal axis.

Identifying surging glaciers in the Central Karakoram for improved climate change impact assessment

NASA Astrophysics Data System (ADS)

Paul, Frank; Bolch, Tobias; Mölg, Nico; Rastner, Philipp

2015-04-01

Several recent studies have investigated glacier changes in the Karakoram mountain range, a region where glaciers behave differently (mass gain and advancing tongues) compared to most other regions in the world. Attribution of this behaviour to climate change is challenging, as many glaciers in the Karakoram are of surge type and have actively surged in the recent past. The measured changes in length, area, volume or velocity in this region are thus depending on the time-period analysed and include non-climatic components. Hence, a proper analysis of climate change impacts on glaciers in this region requires a separation of the surging from the non-surging glaciers. This is challenging as the former often lack the typical surface characteristics such as looped moraines (e.g. when they are steep and small) and/or they merge (during a surge) with a larger non-surging glacier and create looped moraines on its surface. By analysing time series of satellite images that are available since 1961, the heterogeneous behaviour of glaciers in the Karakoram can be revealed. In this study, we have analysed changes in glacier terminus positions in the Karakoram over different time periods from 1961 to 2014 for several hundred glaciers using Corona KH-4 and KH-4B, Hexagon KH-9, Terra ASTER, and Landsat MSS, TM, ETM+ and OLI satellite data. For the last 15 years, high-speed animations of image time-series reveal details of glacier flow and surge dynamics that are otherwise difficult to detect. For example, several of the larger glaciers with surging tributaries (e.g. Panmah, Sarpo Laggo, Skamri, K2 glacier) are stationary and downwasting despite the mass contributions from the surging glaciers. The analysis of the entire time series reveals a complex pattern of changes through time with retreating, advancing, surging and stationary glaciers that are partly regionally clustered. While most of the non-surging glaciers show only small changes in terminus position (±100 m or less) over the analysed time period, length changes of surging glaciers can exceed several kilometres with a continuum of advance rates and surge durations (from 2 to >10 years). Their highly variable extents have thus to be considered when glacier-specific volume changes and flow velocities are calculated. In the presentation we will show our revised assignment of surging glaciers, their changing extents through time along with an analysis of their variable advance rates, and a spatio-temporal overview of glacier changes over the past 50 years.

Cyclic steps due to the surge-type turbidity currents in flume experiments: effect of surge duration on the topography of steps

NASA Astrophysics Data System (ADS)

Yokokawa, Miwa; Yamano, Junpei; Miyai, Masatomo; Hughes Clarke, John; Izumi, Norihiro

2017-04-01

Field observations of turbidity currents and seabed topography on the Squamish delta in British Columbia, Canada revealed that cyclic steps formed by the surge-type turbidity currents (e.g., Hughes Clarke et al., 2014). The high-density portion of the flow, which affects the sea floor morphology, lasted only 30-60 seconds. We are doing flume experiments aiming to investigate the relationship between the condition of surges and topography of resultant steps. In this presentation, we are going to discuss about the effect of surge duration on the topography of steps. The experiments have been performed at Osaka Institute of Technology. A flume, which is 7.0 m long, 0.3 m deep and 2 cm wide, was suspended in a larger tank, which is 7.6 m long, 1.2 m deep and 0.3 m wide, filled with water. The inner flume tilted at 7 degrees. As a source of turbidity currents, mixture of salt water (1.17 g/cm^3) and plastic particles (1.3 g/cm^3, 0.1-0.18 mm in diameter) was prepared. The concentration of the sediments was 6.1 weight % (5.5 volume %) in the head tank. This mixture of salt water and plastic particles poured into the upstream end of the inner flume from head tank for 3 seconds or 7 seconds. 140 surges were made respectively. Discharge of the currents were fluctuated but range from 306 to 870 mL for 3s-surge, and from 1134 to 2030 mL for 7s-surge. As a result, five or six steps were formed respectively. At the case of 3s-surge, steps located at upstream portion of the flume moved vigorously toward upstream direction, whereas steps at downstream portion of the flume moved toward upstream direction at the case of 7s-surge. The wavelengths and wave heights of the steps by 3s-surge are larger than those of 7s-surge at the upstream portion of the flume, but the size of steps of 3s-surge are smaller than those of 7s-surge at the downstream portion of the flume. In this condition of slope and concentration, the longer surge duration, i.e. larger discharge of the current transports the sediment further and makes the steps larger and active at the further location from the source of the currents.

Transfusion-Associated Microchimerism in Combat Casualties

DTIC Science & Technology

2007-10-01

Hathaway WE, Brangle RW, Nelson TL, Roeckel IE. Aplastic anemia and alyphocytosis in an infant with hypogammaglobulinemia: graft-versus-host...multiple organ failure. Arch Surg. 1997; 132:620–624. 32. Dunne JR, Malone DL, Tracy JK, et al. Perioperative anemia : an independent risk factor for

Sea-level rise induced amplification of coastal protection design heights.

PubMed

Arns, Arne; Dangendorf, Sönke; Jensen, Jürgen; Talke, Stefan; Bender, Jens; Pattiaratchi, Charitha

2017-01-06

Coastal protection design heights typically consider the superimposed effects of tides, surges, waves, and relative sea-level rise (SLR), neglecting non-linear feedbacks between these forcing factors. Here, we use hydrodynamic modelling and multivariate statistics to show that shallow coastal areas are extremely sensitive to changing non-linear interactions between individual components caused by SLR. As sea-level increases, the depth-limitation of waves relaxes, resulting in waves with larger periods, greater amplitudes, and higher run-up; moreover, depth and frictional changes affect tide, surge, and wave characteristics, altering the relative importance of other risk factors. Consequently, sea-level driven changes in wave characteristics, and to a lesser extent, tides, amplify the resulting design heights by an average of 48-56%, relative to design changes caused by SLR alone. Since many of the world's most vulnerable coastlines are impacted by depth-limited waves, our results suggest that the overall influence of SLR may be greatly underestimated in many regions.

30 CFR 77.209 - Surge and storage piles.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Surge and storage piles. 77.209 Section 77.209... Installations § 77.209 Surge and storage piles. No person shall be permitted to walk or stand immediately above a reclaiming area or in any other area at or near a surge or storage pile where the reclaiming...

30 CFR 77.209 - Surge and storage piles.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Surge and storage piles. 77.209 Section 77.209... Installations § 77.209 Surge and storage piles. No person shall be permitted to walk or stand immediately above a reclaiming area or in any other area at or near a surge or storage pile where the reclaiming...

Determining Coastal Hazards Risk Perception to Enhance Local Mitigation Planning through a Participatory Mapping Approach

NASA Astrophysics Data System (ADS)

Bethel, M.; Braud, D.; Lambeth, T.; Biber, P.; Wu, W.

2017-12-01

Coastal community leaders, government officials, and natural resource managers must be able to accurately assess and predict a given coastal landscape's sustainability and/or vulnerability as coastal habitat continues to undergo rapid and dramatic changes associated with natural and anthropogenic activities such as accelerated relative sea level rise (SLR). To help address this information need, a multi-disciplinary project team conducted Sea Grant sponsored research in Louisiana and Mississippi with traditional ecosystem users and natural resource managers to determine a method for producing localized vulnerability and sustainability maps for projected SLR and storm surge impacts, and determine how and whether the results of such an approach can provide more useful information to enhance hazard mitigation planning. The goals of the project are to develop and refine SLR visualization tools for local implementation in areas experiencing subsidence and erosion, and discover the different ways stakeholder groups evaluate risk and plan mitigation strategies associated with projected SLR and storm surge. Results from physical information derived from data and modeling of subsidence, erosion, engineered restoration and coastal protection features, historical land loss, and future land projections under SLR are integrated with complimentary traditional ecological knowledge (TEK) offered by the collaborating local ecosystem users for these assessments. The data analysis involves interviewing stakeholders, coding the interviews for themes, and then converting the themes into vulnerability and sustainability factors. Each factor is weighted according to emphasis by the TEK experts and number of experts who mention it to determine which factors are the highest priority. The priority factors are then mapped with emphasis on the perception of contributing to local community vulnerability or sustainability to SLR and storm surge. The maps are used by the collaborators to benefit local hazard mitigation and adaptation planning. The results to date in achieving the project objectives will be presented that include: analyses of scientific field data collected related to marsh vegetation biomass characteristics, analyses of TEK data collected, and mapping products developed.

Numerical Analysis of Storm Surge and Seiche at Tokyo Bay caused by the 2 Similar Typhoons, Typhoon Phanphon and Vongfong in 2014

NASA Astrophysics Data System (ADS)

Iwamoto, T.; Takagawa, T.

2017-12-01

A long period damped oscillation, or seiche, sometimes happens inside a harbor after passing typhoon. For some cases, a maximum sea level is observed due to the superposition of astronomical tide and seiche rather than a peak of storm surge. Hence to clarify seiche factors for reducing disaster potential is important, a long-period seiche with a fundamental period of 5.46 hours in Tokyo Bay (Konishi, 2008) was investigated through numerical simulations and analyses. We examined the case of Typhoon Phanphon and Vongfong in 2014 (Hereafter Case P and V). The intensity and moving velocity were similar and the best-tracks were an arc-shaped, typical one approaching to Tokyo Bay. The track of Case V was about 1.5 degree higher latitude than that of Case P, only Typhoon Phanphon caused significant seiche.Firstly, numerical simulations for the 2 storm surges at Tokyo Bay were conducted by Regional Ocean Modeling System (ROMS) and Meso-Scale Model Grid Point Values (MSM-GPV). MSM-GPV gave the 10m wind speed and Sea Level Pressure (SLP), especially the Mean Error (ME) and Root Mean Squire Error (RMSE) of SLP were low compared to the 12 JMA observation points data (Case P: ME -0.303hPa, RMSE 1.87hPa, Case V: ME -0.285hPa, RMSE 0.74hPa). The computational results showed that the maximum of storm surge was underestimated but the difference was less than 20cm at 5 observation points in Tokyo Bay(Fig.1, 2).Then, power spectrals, coherences and phase differences of storm surges at the 5 observation points were obtained by spectral analysis of observed and simulated waveforms. For Case P, the phase-difference between the bay mouth and innermost part of Tokyo Bay was little, and coherence was almost 1(Fig.3, 4). However, for Case V, coherence was small around the fundamental period of 5.46 hours. Furthermore, Empirical Orthogonal Function (EOF) analysis of storm surge, SLP and sea surface stress were conducted. The contributions of EOF1 were above 90% for the all variables, the gradient of storm surge EOF1 was parallel to the bay axis for Case P, but about 50-degree oblique from the axis for Case V(Fig.5, 6). In addition, the EOF1 of SLP for Case P showed a concentric circle structure above Tokyo Bay, besides the structure was not appeared for Case V.

The Response of Extreme Precipitation to Climate Change in the North American Monsoon Region

NASA Astrophysics Data System (ADS)

Pascale, S.; Bordoni, S.; Kapnick, S. B.; Delworth, T. L.; Murakami, H.

2017-12-01

Gulf of California moisture surges (GoC surges) transport lower-level moisture in the southwestern United States and can trigger widespread convective bursts during the summertime North American monsoon (NAM). The intensity of such bursts varies over a wide spectrum, going from drier-than-average to extremely intense and persisting events. In this study we use a 50 km-horizontal resolution global coupled model (FLOR) developed at the NOAA Geophysical Fluid Dynamics Laboratory and featuring a realistic simulation of the GoC surges. We evaluate the model's ability to reproduce the intensity of precipitation during GoC surge and non-surge periods in present and doubled CO2 climatic conditions. We find that the mean number of GoC surge events per monsoon season (i.e., approximately 15) is not significantly affected by CO2 forcing. Nevertheless, when SST biases are minimized through flux adjustment, FLOR predicts a reduction in monsoonal precipitation over the southwestern United States. Our simulations further suggest that surge-related rainfall adjusts towards lower and higher percentiles, while becoming less important at intermediate values. Convective precipitation not occurring during GoC surges is instead not coherently affected by doubled CO2. Finally, the influence of CO2 forcing on the large-scale drivers of monsoonal precipitation during GoC surge events, such as the position of the monsoonal ridge, is investigated and related to precipitation changes.

Effect of Tide Elevation on Extratropical Storm Surge in Northwest Europe

NASA Astrophysics Data System (ADS)

Keshtpoor, M.; Carnacina, I.; Yablonsky, R. M.

2016-12-01

Extratropical cyclones (ETCs) are the major storm surge-generating meteorological events in northwest Europe. The total water level increase induced by these ETCs is significantly influenced by the local tidal range, which exceeds 8 meters along the southwestern UK coastline. In particular, a surge-generating ETC during high tide may put coastal assets and infrastructure in risk. Also, during low tide, the risk of surge induced by extreme ETC events is diminished. Here, the effect of tidal elevation on storm surge is investigated at 196 tide gauges in northwest Europe. A numerical, hydrodynamic model was developed using Delft3D-FM framework to simulate the coastal hydrodynamics during ETCs. Then, 1750 historical events were simulated to investigate the pattern of coastal inundation. Results suggest that in areas with a large tidal range ( 8 meters) and during the time period surrounding high or low tide, the pattern of coastal hydrodynamics is governed by tide and not storm surge. This result is most evident near the English Channel and Bristol Channel, where low frequency maximum water levels are observed when storm surge is combined with high tide. In contrast, near the tidal phase reversal, coastal hydrodynamics responds primarily to the storm surge, and low frequency maximum water elevation largely depends on the surge. In the areas with a small tidal range, ETC strength determines the pattern of coastal inundation.

Role of cold surge and MJO on rainfall enhancement over indonesia during east asian winter monsoon

NASA Astrophysics Data System (ADS)

Fauzi, R. R.; Hidayat, R.

2018-05-01

Intensity of precipitation in Indonesia is influenced by convection and propagation of southwest wind. Objective of this study is to analyze the relationship between cold surge and the phenomenon of intra-seasonal climate variability Madden-julian Oscillation (MJO) for affecting precipitation in Indonesia. The data used for identifying the occurrence of cold surge are meridional wind speed data from the ERA-Interim. In addition, this study also used RMM1 and RMM2 index data from Bureau of Meteorology (BOM) for identifying MJO events. The results showed that during East Asian Winter Monsoon (EAWM) in 15 years (2000-2015), there are 362 cold surge events, 186 MJO events, and 113 cold surge events were associated with MJO events. The spread of cold surge can penetrate to equator and brought mass of water vapor that causes dominant precipitation in the Indonesian Sea up to 50-75% from climatological precipitation during EAWM. The MJO convection activity that moves from west to east also increases precipitation, but the distribution of rainfall is wider than cold surge, especially in Eastern Indonesia. MJO and cold surge simultaneously can increase rainfall over 100-150% in any Indonesian region that affected by MJO and cold surge events. The mechanism of heavy rainfall is illustrated by high activity of moisture transport in areas such as Java Sea and coastal areas of Indonesia.

Mapping Dependence Between Extreme Rainfall and Storm Surge

NASA Astrophysics Data System (ADS)

Wu, Wenyan; McInnes, Kathleen; O'Grady, Julian; Hoeke, Ron; Leonard, Michael; Westra, Seth

2018-04-01

Dependence between extreme storm surge and rainfall can have significant implications for flood risk in coastal and estuarine regions. To supplement limited observational records, we use reanalysis surge data from a hydrodynamic model as the basis for dependence mapping, providing information at a resolution of approximately 30 km along the Australian coastline. We evaluated this approach by comparing the dependence estimates from modeled surge to that calculated using historical surge records from 79 tide gauges around Australia. The results show reasonable agreement between the two sets of dependence values, with the exception of lower seasonal variation in the modeled dependence values compared to the observed data, especially at locations where there are multiple processes driving extreme storm surge. This is due to the combined impact of local bathymetry as well as the resolution of the hydrodynamic model and its meteorological inputs. Meteorological drivers were also investigated for different combinations of extreme rainfall and surge—namely rain-only, surge-only, and coincident extremes—finding that different synoptic patterns are responsible for each combination. The ability to supplement observational records with high-resolution modeled surge data enables a much more precise quantification of dependence along the coastline, strengthening the physical basis for assessments of flood risk in coastal regions.

Storm surge evolution and its relationship to climate oscillations at Duck, NC

NASA Astrophysics Data System (ADS)

Munroe, Robert; Curtis, Scott

2017-07-01

Coastal communities experience increased vulnerability during storm surge events through the risk of damage to coastal infrastructure, erosion/deposition, and the endangerment of human life. Policy and planning measures attempt to avoid or mitigate storm surge consequences through building codes and setbacks, beach stabilization, insurance rates, and coastal zoning. The coastal emergency management community and public react and respond on shorter time scales, through temporary protection, emergency stockpiling, and evacuation. This study utilizes time series analysis, the Kolmogorov-Smirnov (K-S) test, Pearson's correlation, and the generalized extreme value (GEV) theorem to make the connection between climate oscillation indices and storm surge characteristics intra-seasonally to inter-annually. Results indicate that an El Niño (+ENSO), negative phase of the NAO, and positive phase of the PNA pattern all support longer duration and hence more powerful surge events, especially in winter. Increased surge duration increases the likelihood of extensive erosion, inland inundation, among other undesirable effects of the surge hazard.

Centrifugal compressor controller for minimizing power consumption while avoiding surge

DOE Office of Scientific and Technical Information (OSTI.GOV)

Haley, P.F.; Junk, B.S.; Renaud, M.A.

1987-08-18

For use with a variable capacity centrifugal compressor driven by an electric motor, a controller is described for adjusting the capacity of the compressor to satisfy a demand, minimize electric power consumption and avoid a surge condition. The controller consists of: a. means for sensing an operating parameter that is indicative of the capacity of the compressor; b. means for setting a selected setpoint that represents a desired value of the operating parameter; c. surge sensing means for detecting an impending surge by sensing fluctuation in the electric current supplied to the compressor motor, wherein an impending surge is detectedmore » whenever fluctuations in excess of a predetermined amplitude occur in excess of a predetermined frequency; and d. control means, responsive to the operating parameter sensing means, the setpoint setting means, and the surge sensing means, for controlling the compressor, such that its capacity is minimally above a level that would cause a surge condition yet is sufficient to maintain the operating parameter at the setpoint.« less

Geodetic measurements used to estimate ice transfer during Bering Glacier surge

NASA Astrophysics Data System (ADS)

Sauber, Jeanne; Plafker, George; Gipson, John

The application of geodetic measurements to glacial research has found a new testing ground: near a surging Alaskan glacier. A set of geodetic measurements collected adjacent to the Bagley Icefield (Figure 1) and along the Gulf of Alaska (Figure 2) are being used to estimate the effects of the Bering Glacier surge that began in the spring of 1993. When ice is removed from a glacier's reservoir during a surge, its surface lowers by tens or hundreds of meters and ice is added to the receiving area, where it thickens and advances.The dramatic changes in a surging glacier's extent and thickness should result in elastic deformation of the solid Earth. At Bering Glacier, calculations show that ice transfer may have caused up to 17 cm of the solid Earth to subside. Although recent surges at the Bering and Variegated Glaciers have been well documented, little is known about most surges, particularly about what happens in the upper reaches of the glaciers.

Multidecadal Scale Detection Time for Potentially Increasing Atlantic Storm Surges in a Warming Climate

NASA Astrophysics Data System (ADS)

Lee, Benjamin Seiyon; Haran, Murali; Keller, Klaus

2017-10-01

Storm surges are key drivers of coastal flooding, which generate considerable risks. Strategies to manage these risks can hinge on the ability to (i) project the return periods of extreme storm surges and (ii) detect potential changes in their statistical properties. There are several lines of evidence linking rising global average temperatures and increasingly frequent extreme storm surges. This conclusion is, however, subject to considerable structural uncertainty. This leads to two main questions: What are projections under various plausible statistical models? How long would it take to distinguish among these plausible statistical models? We address these questions by analyzing observed and simulated storm surge data. We find that (1) there is a positive correlation between global mean temperature rise and increasing frequencies of extreme storm surges; (2) there is considerable uncertainty underlying the strength of this relationship; and (3) if the frequency of storm surges is increasing, this increase can be detected within a multidecadal timescale (≈20 years from now).

Cataloging: Librarianship's Best Bargain.

ERIC Educational Resources Information Center

Morris, Dilys E.; Wool, Gregory

1999-01-01

Iowa State University's cost study proves academic librarians can keep cataloging in-house and save staff costs. Several factors play a role in the productivity surge at ISU: increasing use of shared cataloging; growth of online authoring files; expanding role of support staff; increasing automation of catalogers' work; and structural flattening…

Surge of Bering Glacier and Bagley Ice Field: Parameterization of surge characteristics based on automated analysis of crevasse image data and laser altimeter data

NASA Astrophysics Data System (ADS)

Stachura, M.; Herzfeld, U. C.; McDonald, B.; Weltman, A.; Hale, G.; Trantow, T.

2012-12-01

The dynamical processes that occur during the surge of a large, complex glacier system are far from being understood. The aim of this paper is to derive a parameterization of surge characteristics that captures the principle processes and can serve as the basis for a dynamic surge model. Innovative mathematical methods are introduced that facilitate derivation of such a parameterization from remote-sensing observations. Methods include automated geostatistical characterization and connectionist-geostatistical classification of dynamic provinces and deformation states, using the vehicle of crevasse patterns. These methods are applied to analyze satellite and airborne image and laser altimeter data collected during the current surge of Bering Glacier and Bagley Ice Field, Alaska.

Artificial Neural Network forecasting of storm surge water levels at major estuarine ports to supplement national tide-surge models and improve port resilience planning

NASA Astrophysics Data System (ADS)

French, Jon; Mawdsley, Robert; Fujiyama, Taku; Achuthan, Kamal

2017-04-01

Effective prediction of tidal storm surge is of considerable importance for operators of major ports, since much of their infrastructure is necessarily located close to sea level. Storm surge inundation can damage critical elements of this infrastructure and significantly disrupt port operations and downstream supply chains. The risk of surge inundation is typically approached using extreme value analysis, while short-term forecasting generally relies on coastal shelf-scale tide and surge models. However, extreme value analysis does not provide information on the duration of a surge event and can be sensitive to the assumptions made and the historic data available. Also, whilst regional tide and surge models perform well along open coasts, their fairly coarse spatial resolution means that they do not always provide accurate predictions for estuarine ports. As part of a NERC Environmental Risks to Infrastructure Innovation Programme project, we have developed a tool that is specifically designed to forecast the North Sea storm surges on major ports along the east coast of the UK. Of particular interest is the Port of Immingham, Humber estuary, which handles the largest volume of bulk cargo in the UK including major flows of coal and biomass for power generation. A tidal surge in December 2013, with an estimated return period of 760 years, partly flooded the port, damaged infrastructure and disrupted operations for several weeks. This and other recent surge events highlight the need for additional tools to supplement the national UK Storm Tide Warning Service. Port operators are also keen to have access to less computationally expensive forecasting tools for scenario planning and to improve their resilience to actual events. In this paper, we demonstrate the potential of machine learning methods based on Artificial Neural Networks (ANNs) to generate accurate short-term forecasts of extreme water levels at estuarine North Sea ports such as Immingham. An ANN is configured to take advantage of far-field information on developing tidal surges provided by tide gauges in NW Scotland (the 'external surge'), supported by observations of wind and atmospheric pressure and the predicted astronomical tide at Immingham. Missing data can cause problems with ANN models and a novel aspect of our implementation is the use of multiple redundant inputs (nearby tide gauges that experience a high degree of surge coherence) to synthesise a single external surge input. A similar approach is taken with meteorological forcings, creating an ANN that is resilient against data drop-outs within its input vector. The ANN generates 6 to 24 hour surge forecasts at Immingham with accuracy better than the present UK Storm Tide Warning Service. These can be used to cross-check national forecasts, generate more accurate estimates of likely flood depths, timings and durations and trigger planned responses to severe forecasts. Crucially, this capability can be 'owned' by the port operator, which encourages the development of a shared understanding of storm surge hazards and the challenges of port resilience planning between scientist and stakeholder.

Observing storm surges from satellite altimetry

NASA Astrophysics Data System (ADS)

Han, Guoqi

2016-07-01

Storm surges can cause catastrophic damage to properties and loss of life in coastal communities. Thus it is important to enhance our capabilities of observing and forecasting storm surges for mitigating damage and loss. In this presentation we show examples of observing storm surges around the world using nadir satellite altimetry, during Hurricane Sandy, Igor, and Isaac, as well as other cyclone events. The satellite observations are evaluated against tide-gauge observations and discussed for dynamic mechanisms. We also show the potential of a new wide-swath altimetry mission, the Surface Water and Ocean Topography (SWOT), for observing storm surges.

Storm surges in the White and Barents Seas: formation, statistics, analysis

NASA Astrophysics Data System (ADS)

Korablina, Anastasia; Arkhipkin, Victor

2017-04-01

Arctic seas storm surges investigation are high priority in Russia due to the active development of offshore oil and gas, construction of facilities in the coastal zone, as well as for the navigation safety. It is important to study the surges variability, to predict this phenomena and subsequent economic losses, thus including such information into the Russian Arctic Development Program 2020. White and Barents Seas storm surges are caused mainly by deep cyclones of two types: "diving" from the north (88% of all cyclones) and Atlantic from the west. The surge height was defined as the excess of the level that was obtained as the difference between the observed level and subtracting tide level and low-frequency level. The period of low-frequency level oscillation was determined by spectral analysis of the in-situ data. ADCIRC model is used for calculating the storm surge height. We did the calculations on unstructured grid with variable step from 50 to 5000 m. The ADCIRC model was based on the data on wind field, the sea level pressure, the concentration of ice reanalysis CFSR (1979-2010) in increments 0.3°, CFSv2 (2011-2015) in increments 0.2°. On the boundary conditions harmonic constants from Finite Element Solution tide model 2004 (FES2004) in increments 1/8° were set. The following stations on the coast Varandey, Pechora Bay, Chosha Bay, Severodvinsk, Onega, Solovki and other were selected for the storm surges statistical analysis in the period 1979-2015. The number of storm surges (> 0.3 m) long-term variability was obtained, the number of surges at a height (m) range (0.3-0.6, 0.6-0.9, 0.9-1.2, >1.2) was estimated. It shows that 1980 and 1998 are the years with the fewest number storms. For example, the largest number of storm surge (53) was observed in 1995 in Varandey. The height of the surge, possible only once in 100 years, is counted. This maximum height (m) of the surge was noted in Varandey (4.1), Chosha Bay (3.4), Barents Sea, Onega Bay (2.4), White Sea. Quantitative assessment of the pressure and wind contributing to the surge formation was made. The analysis has shown that the wind has a larger contribution (90%) to surge formation in the study area. The study was performed in the framework of the Russian Science Foundation (project 14-37-00038).

Reassessing Storm Surge Risk for New York City (Invited)

NASA Astrophysics Data System (ADS)

Lin, N.; Emanuel, K.

2013-12-01

New York City (NYC) is highly vulnerable to tropical cyclone (TC) storm surge flooding. In a previous study, we coupled a (reanalysis- or GCM-driven) hurricane model with hydrodynamic models to simulate large numbers of synthetic surge events under observed and projected climates and assess surge threat for NYC. The storm surge return levels under the current and future climates (IPCC AR4 A1B scenario) were obtained. The results showed that the distribution of surge levels may shift to higher values in the future by a magnitude comparable to the projected sea-level rise. The study focused on typical TCs that have a storm size of the climatological mean for the Atlantic Basin and pass within a 200-km radius of the Battery, NYC. In October 2012, Hurricane Sandy, a barely Category-1 storm that made landfall about 200-km southwest from the Battery, caused the highest surge flooding of the instrumental record (~3.5 m above the mean sea level or ~2.8 m surge over the high tide) at the Battery. The extreme surge was due to the fact that the storm was a 'hybrid' event, undergoing extensive extratropical transition when making landfall almost perpendicularly to the NJ coast with an unusually large size. Sandy's case calls for a reassessment of storm surge risk for NYC that account for the special features of the storms in this region. In this reassessment, we account for the effect of extratropical transition on the wind fields through improving the surface background wind estimation, which was assumed to be uniform for typical TCs, by developing a representation of the interaction between the highly localized potential vorticity anomaly of the TC and its environmental baroclinic fields. We account for the storm size variation through incorporating the full probability distribution of the size for the region. Our preliminary results show that estimated wind and surge return levels are much higher with the effect of extratropical transition. The effect of the storm size variation is relatively large in the upper tail of the surge distribution. Also, we will update the prediction for future climates using the IPCC AR5 RCP 8.5 and RCP 4.5 scenarios, and extend our focus area further south to capture storms that can induce high surges at the Battery, although making landfall relatively further away on the NJ coast. The results will be compared with those using the AR4 scenario in our previous study. The combined effects of storm climatology change and sea level rise on the risk of NYC surge flooding will be discussed.

Development and validation of a surgical workload measure: the surgery task load index (SURG-TLX).

PubMed

Wilson, Mark R; Poolton, Jamie M; Malhotra, Neha; Ngo, Karen; Bright, Elizabeth; Masters, Rich S W

2011-09-01

The purpose of the present study was to develop and validate a multidimensional, surgery-specific workload measure (the SURG-TLX), and to determine its utility in providing diagnostic information about the impact of various sources of stress on the perceived demands of trained surgical operators. As a wide range of stressors have been identified for surgeons in the operating room, the current approach of considering stress as a unidimensional construct may not only limit the degree to which underlying mechanisms may be understood but also the degree to which training interventions may be successfully matched to particular sources of stress. The dimensions of the SURG-TLX were based on two current multidimensional workload measures and developed via focus group discussion. The six dimensions were defined as mental demands, physical demands, temporal demands, task complexity, situational stress, and distractions. Thirty novices were trained on the Fundamentals of Laparoscopic Surgery (FLS) peg transfer task and then completed the task under various conditions designed to manipulate the degree and source of stress experienced: task novelty, physical fatigue, time pressure, evaluation apprehension, multitasking, and distraction. The results were supportive of the discriminant sensitivity of the SURG-TLX to different sources of stress. The sub-factors loaded on the relevant stressors as hypothesized, although the evaluation pressure manipulation was not strong enough to cause a significant rise in situational stress. The present study provides support for the validity of the SURG-TLX instrument and also highlights the importance of considering how different stressors may load surgeons. Implications for categorizing the difficulty of certain procedures, the implementation of new technology in the operating room (man-machine interface issues), and the targeting of stress training strategies to the sources of demand are discussed. Modifications to the scale to enhance clinical utility are also suggested.

Examination of the influence of environmental factors on contaminant vapor concentration attenuation factors using the U.S. EPA's vapor intrusion database.

PubMed

Yao, Yijun; Shen, Rui; Pennell, Kelly G; Suuberg, Eric M

2013-01-15

Those charged with the responsibility of estimating the risk posed by vapor intrusion (VI) processes have often looked to information contained in the U.S. Environmental Protection Agency (EPA)'s VI database for insight. Indoor air concentration attenuation factors have always been a key focus of this database, but the roles of different environmental factors in these attenuation processes are still unclear. This study aims to examine the influences of these factors in the context of the information in the VI database. The database shows that the attenuation factors vary over many orders of magnitude and that no simple statistical fluctuation around any typical mean value exists. Thus far, no simple explanation of this phenomenon has been presented. This paper examines various possible contributing factors to the enormous range of observed values, looking at which ones can plausibly contribute to explaining them.

The influence of sea surface temperature on the intensity and associated storm surge of tropical cyclone Yasi: a sensitivity study

NASA Astrophysics Data System (ADS)

Lavender, Sally L.; Hoeke, Ron K.; Abbs, Deborah J.

2018-03-01

Tropical cyclones (TCs) result in widespread damage associated with strong winds, heavy rainfall and storm surge. TC Yasi was one of the most powerful TCs to impact the Queensland coast since records began. Prior to Yasi, the SSTs in the Coral Sea were higher than average by 1-2 °C, primarily due to the 2010/2011 La Niña event. In this study, a conceptually simple idealised sensitivity analysis is performed using a high-resolution regional model to gain insight into the influence of SST on the track, size, intensity and associated rainfall of TC Yasi. A set of nine simulations with uniform SST anomalies of between -4 and 4 °C applied to the observed SSTs are analysed. The resulting surface winds and pressure are used to force a barotropic storm surge model to examine the influence of SST on the associated storm surge of TC Yasi. An increase in SST results in an increase in intensity, precipitation and integrated kinetic energy of the storm; however, there is little influence on track prior to landfall. In addition to an increase in precipitation, there is a change in the spatial distribution of precipitation as the SST increases. Decreases in SSTs result in an increase in the radius of maximum winds due to an increase in the asymmetry of the storm, although the radius of gale-force winds decreases. These changes in the TC characteristics also lead to changes in the associated storm surge. Generally, cooler (warmer) SSTs lead to reduced (enhanced) maximum storm surges. However, the increase in surge reaches a maximum with an increase in SST of 2 °C. Any further increase in SST does not affect the maximum surge but the total area and duration of the simulated surge increases with increasing upper ocean temperatures. A large decrease in maximum storm surge height occurs when a negative SST anomaly is applied, suggesting if TC Yasi had occurred during non-La Niña conditions the associated storm surge may have been greatly diminished, with a decrease in storm surge height of over 3 m when the SST is reduced by 2 °C. In summary, increases in SST lead to an increase in the potential destructiveness of TCs with regard to intensity, precipitation and storm surge, although this relationship is not linear.

Linking storm surge activity and circulation variability along the Spanish coast through a synoptic pattern classification

NASA Astrophysics Data System (ADS)

Rasilla Álvarez, Domingo; Garcia Codrón, Juan Carlos

2010-05-01

The potentially negative consequences resulting from the estimations of global sea level rising along the current century are a matter of serious concern in many coastal areas worldwide. Most of the negative consequences of the sea level variability, such as flooding or erosion, are linked to episodic events of strong atmospheric forcing represented by deep atmospheric disturbances, especially if they combine with extreme astronomical high tides. Moreover, the interaction between the prevailing flows during such events and the actual orientation of the coast line might accelerate or mitigate such impacts. This contribution analyses sea surge variations measured at five tide-gauge stations located around the Iberian Peninsula and their relationships with regional scale circulation patterns with local-scale winds. Its aim is to improve the knowledge of surge related-coastal-risks by analysing the relationship between surges and their atmospheric forcing factors at different spatial scales. The oceanographic data set consists of hourly data from 5 tide gauge stations (Santander, Vigo, Bonanza, Málaga, Valencia and Barcelona) disseminated along the Spanish coastline, provided by Puertos del Estado. To explore the atmospheric mechanisms responsible for the sign and magnitude of sea surges, a regional Eulerian approach (a synoptic typing) were combined with a larger-scale Lagrangian method, based on the analysis of storm-tracks over the Atlantic and local information (synop reports) obtained from the closest meteorological stations to the tide gauges. The synoptic catalogue was obtained following a procedure that combines Principal Component Analysis (PCA) for reduction purposes and clustering (Ward plus K-means) to define the circulation types. Sea level pressure, surface 10m U and V wind components gridded data were obtained from NCEP Reanalysis, while storm tracks and cyclone statistics were extracted from the CDC Map Room Climate Products Storm Track Data (http://www.cdc.noaa.gov/map/clim/st_data.html). The second task was to evaluate the performance of each circulation type on the spatial patterns of a daily fire danger risk index (Canadian Fire Weather Index, FWI). Finally, anomaly maps of several surface and low level climate variables, corresponding to the dates of ignition of the very large forest fires within each synoptic pattern, were calculated to provide insight of the specific conditions associated to those extreme events. A principal component analysis upon 6 hourly residuals highlighted the homogeneous behaviour of the tide gauges and provided a regional quantitative index to identify the largest storm surges. The leading PCA displayed a homogeneous spatial pattern, describing the low frequency variability along the entire coast, in spite of different orientations of the coast, accounting for more than 80% of the total variability. The second PCA displayed opposite phases between the Atlantic and the Mediterranean. Furthermore, the results suggest that surges are a regional rather than local phenomenon, probably related to the same single physical forcing. The comparison between extreme surge events and circulation patterns highlighted that single physical mechanism is represented by extratropical cyclonic disturbances located at the north-western corner of the Iberian Peninsula, responsible for an environment characterized by low pressure readings and westerly-southwesterly winds. That wind pattern acquires an onshore component in the Atlantic coast, but becomes offshore in the Mediterranean. So, the main mechanism responsible for those storm surges is the inverse barometer effect, being the wind dragging secondary. The main physical forcing of the storm surges, the extratropical cyclones, have experience a reduction of this frequency and a marked reduction in their strength since 1950, replaced by stable circulations. Both conditions suggest a long term reduction of the frequency and the magnitude of storm surges.

Numerical experiments of dynamical processes during the 2011-2013 surge of the Bering-Bagley Glacier System, using a full-Stokes finite element model

NASA Astrophysics Data System (ADS)

Trantow, Thomas

The Bering-Bagley Glacial System (BBGS) is the largest glacier system outside of the Greenland and Antarctic ice sheets, and is the Earth's largest surge-type glacier. Surging is one of three types of glacial acceleration and the least understood one. Understanding glacial acceleration is paramount when trying to explain ice discharge to the oceans and the glacial contribution to sea-level rise, yet there are currently no numerical glacial models that account for surging. The recent 2011-2013 surge of the BBGS provides a rare opportunity to study the surge process through observations and the subsequent data analysis and numerical modeling. Using radar, altimeter, and image data collected from airborne and satellite missions, various descriptions of ice geometry are created at different times throughout the surge. Using geostatistical estimation techniques including variography and ordinary kriging, surface and bedrock Digital Elevation Maps (DEMs) are derived. A time series analysis of elevation change during the current surge is then conducted and validated using a complete error analysis along with airborne observations. The derived DEMs are then used as inputs to a computer simulated model of glacier dynamics in the BBGS. Using the Finite Element software Elmer/Ice, a full-Stokes simulation, with Glen's flow law for temperate ice, is created for numerical experiments. With consideration of free surface evolution, glacial hydrology and surface mass balance, the model is able to predict a variety of field variables including velocity, stress, strain-rate, pressure and surface elevation change at any point forward in time. These outputs are compared and validated using observational data such as CryoSat-2 altimetry, airborne field data, imagery and previous detailed analysis of the BBGS. Preliminary results reveal that certain surge phenomena such as surface elevation changes, surge progression and locations at which the surge starts, can be recreated using the current model. Documentation of the effects that altering glaciological parameters and boundary conditions have on ice rheology in a large complex glacial system comes as secondary result. Simulations have yet to reveal any quasi-cyclic behavior or natural surge initiation.

A new dynamical index for classification of cold surge types over East Asia

NASA Astrophysics Data System (ADS)

Park, Tae-Won; Ho, Chang-Hoi; Jeong, Jee-Hoon; Heo, Jin-Woo; Deng, Yi

2015-11-01

The cold surges over East Asia can be classified into wave-train type and blocking type according to their dynamic origins. In the present study, two dynamic indices are proposed to objectively identify cold surge types using potential temperature ( θ) on the dynamic tropopause at 2-potential vorticity units (2-PVU) surface. The two indices are designed to represent primary characteristics of the two types of cold surge. The wave-train index ( WI) is defined as a difference of anomalous θ on the 2-PVU surface between the western North Pacific and northeast China, which captures a southward (northward) intrusion of cold (warm) air mass related to the trough-ridge pattern. The blocking index ( BI) is defined as a difference of anomalous θ between the subarctic region and northeast China, which indicates air mass overturning related to a reversal of the usual meridional θ gradient commonly observed in the occurrence of blocking type cold surge. Composite analyses based on the distribution of the WI and BI clearly demonstrate the dynamic evolutions of corresponding cold surge types. The wave-train cold surge is associated with a southeastward expansion of the Siberian High and northerly wind near surface, which is caused by growing baroclinic waves. During the blocking cold surge, a geopotential height dipole indicating the subarctic blocking and deepening of East Asian coastal trough induces a southward expansion of the Siberian High and northeasterly wind. Compared to the wave-train type, the blocking cold surge exhibits a longer duration and stronger intensity. In the new framework of these dynamic indices, we can detect a third type of cold surge when both the wave-train and the blocking occur together. In addition, we can exclude the events that do not have the essential features of the upper tropospheric disturbances or the subarctic anticyclonic circulation, which are responsible for cold surge occurrence, using the new indices.

Surge dynamics and lake outbursts of Kyagar Glacier, Karakoram

NASA Astrophysics Data System (ADS)

Round, Vanessa; Leinss, Silvan; Huss, Matthias; Haemmig, Christoph; Hajnsek, Irena

2017-03-01

The recent surge cycle of Kyagar Glacier, in the Chinese Karakoram, caused formation of an ice-dammed lake and subsequent glacial lake outburst floods (GLOFs) exceeding 40 million m3 in 2015 and 2016. GLOFs from Kyagar Glacier reached double this size in 2002 and earlier, but the role of glacier surging in GLOF formation was previously unrecognised. We present an integrative analysis of the glacier surge dynamics from 2011 to 2016, assessing surge mechanisms and evaluating the surge cycle impact on GLOFs. Over 80 glacier surface velocity fields were created from TanDEM-X (TerraSAR-X add-on for Digital Elevation Measurement), Sentinel-1A, and Landsat satellite data. Changes in ice thickness distribution were revealed by a time series of TanDEM-X elevation models. The analysis shows that, during a quiescence phase lasting at least 14 years, ice mass built up in a reservoir area at the top of the glacier tongue, and the terminus thinned by up to 100 m, but in the 2 years preceding the surge onset this pattern reversed. The surge initiated with the onset of the 2014 melt season, and in the following 15 months velocity evolved in a manner consistent with a hydrologically controlled surge mechanism. Dramatic accelerations coincided with melt seasons, winter deceleration was accompanied by subglacial drainage, and rapid surge termination occurred following the 2015 GLOF. Rapid basal motion during the surge is seemingly controlled by high water pressure, caused by input of surface water into either an inefficient subglacial drainage system or unstable subglacial till. The potential lake volume increased to more than 70 million m3 by late 2016, as a result of over 60 m of thickening at the terminus. Lake formation and the evolution of the ice dam height should be carefully monitored through remote sensing to anticipate large GLOFs in the near future.

7 CFR 58.237 - Condensed surge supply.

Code of Federal Regulations, 2010 CFR

2010-01-01

..., GENERAL SPECIFICATIONS FOR APPROVED PLANTS AND STANDARDS FOR GRADES OF DAIRY PRODUCTS 1 General... Procedures § 58.237 Condensed surge supply. Surge tanks or balance tanks if used between the evaporators and...

Taking a Regional Healthcare Coalition Approach to Mitigating Surge Capacity Needs of Mass Casualty or Pandemic Events

DTIC Science & Technology

2012-06-01

participation needs of a coalition—active involvement. In the book Work and the Nature of Man, Frederick Hertzberg details his “ two - factor theory ” in...gaining motivation for employees or, as exemplified in this case, coalition participants.59 The theory posits that there are two factors that...59 Frederick Hertzberg; Work and the Nature of Man; 1973; Mentor Books, New York; Two - factor Theory Pp. 149-158 60 Hertzberg’s

The effect of changing topography on coastal tides and storm surge: a historical perspective

NASA Astrophysics Data System (ADS)

Talke, Stefan; Jay, David; Helaire, Lumas; Familkhalili, Ramin

2016-11-01

Over decadal and century time scales, the topography of coastal harbors changes due to natural and anthropogenic factors. These changes alter the mass and momentum balances of incoming waves, producing measureable changes to tides and surge. Here we use recently recovered archival data, historic bathymetric charts, and numerical models to assess changes in multiple estuaries. In the Columbia River estuary, Ems estuary, and Cape Fear Estuary, channel deepening has increased the M2 tide between 10 to 100% since the 19th century, due to both reduced frictional effects and altered resonance. The bathymetric perturbations also affect the propagation of other long-period waves: in Wilmington (NC), the worst-case scenario CAT-5 storm surge is modeled to increase by 50% since 19th century conditions. Similarly, in New York harbor, the 10 year storm-tide level has outpaced sea-level rise by nearly 30 cm since 1850. In the Columbia River, reduced friction has decreased the river slope (reducing water levels), but also led to amplification of both tides and flood waves. Going forward, historical bathymetric change may provide a clue to the future effects of climate change and continued anthropogenic development. National Science Foundation; US Army Corp of Engineers.

Tree mortality following prescribed fire and a storm surge event in Slash Pine (pinus elliottii var. densa) forests in the Florida Keys, USA

USGS Publications Warehouse

Sah, Jay P.; Ross, Michael S.; Snyder, James R.; Ogurcak, Danielle E.

2010-01-01

In fire-dependent forests, managers are interested in predicting the consequences of prescribed burning on postfire tree mortality. We examined the effects of prescribed fire on tree mortality in Florida Keys pine forests, using a factorial design with understory type, season, and year of burn as factors. We also used logistic regression to model the effects of burn season, fire severity, and tree dimensions on individual tree mortality. Despite limited statistical power due to problems in carrying out the full suite of planned experimental burns, associations with tree and fire variables were observed. Post-fire pine tree mortality was negatively correlated with tree size and positively correlated with char height and percent crown scorch. Unlike post-fire mortality, tree mortality associated with storm surge from Hurricane Wilma was greater in the large size classes. Due to their influence on population structure and fuel dynamics, the size-selective mortality patterns following fire and storm surge have practical importance for using fire as a management tool in Florida Keys pinelands in the future, particularly when the threats to their continued existence from tropical storms and sea level rise are expected to increase.

Remote-sensing-based analysis of the 1996 surge of Northern Inylchek Glacier, central Tien Shan, Kyrgyzstan

NASA Astrophysics Data System (ADS)

Häusler, Hermann; Ng, Felix; Kopecny, Alexander; Leber, Diethard

2016-11-01

The evolution of Northern Inylchek Glacier and its proglacial lake - Upper Lake Merzbacher - during its 1996 surge and the surrounding decades is analyzed with remote sensing imagery. Overall retreat of the glacier from 1943 to 1996 enlarged the lake to 4 km long and ≈ 100 m deep. The surge in 1996 initiated between 12 September and 7 October and advanced the glacier by 3.7 km to override most of Upper Lake Merzbacher. The surge phase probably ended in December 1996 and involved mean flow velocities across the lower trunk of the glacier that reached 50 m d- 1 over a 32-day period. Water displaced by the surge from Upper Lake Merzbacher, totalling 1.5 × 108 m3 in volume, accelerated filling of Lower Lake Merzbacher downvalley and helped trigger this marginal ice-dammed lake to outburst in a jökulhlaup around late November/early December. The characteristics and duration of the surge render it as similar to temperate glacier surges elsewhere. It may have been facilitated by low basal friction caused by water-saturated sediments in the upper lake bed. Furthermore, bathymetric measurements show that the surge evacuated much sediment into the upper lake, causing its depth to reduce from 20 to 30 m in 1996 to 8 m by 2005 and 2 m by 2011; the corresponding deposition rates imply glacier-catchment specific mean sediment yields of 1.4 to 3.4 × 103 Mg km- 2 a- 1 in the years after the surge. Our study documents novel interactions within a cascade system of glaciers and lakes that exhibits surging and outburst-flood behavior.

Developmental Programming: Postnatal Steroids Complete Prenatal Steroid Actions to Differentially Organize the GnRH Surge Mechanism and Reproductive Behavior in Female Sheep

PubMed Central

Jackson, Leslie M.; Mytinger, Andrea; Roberts, Eila K.; Lee, Theresa M.; Foster, Douglas L.; Padmanabhan, Vasantha

2013-01-01

In female sheep, estradiol (E2) stimulates the preovulatory GnRH/LH surge and receptive behavior, whereas progesterone blocks these effects. Prenatal exposure to testosterone disrupts both the positive feedback action of E2 and sexual behavior although the mechanisms remain unknown. The current study tested the hypothesis that both prenatal and postnatal steroids are required to organize the surge and sex differences in reproductive behavior. Our approach was to characterize the LH surge and mating behavior in prenatally untreated (Control) and testosterone-treated (T) female sheep subsequently exposed to one of three postnatal steroid manipulations: endogenous E2, excess E2 from a chronic implant, or no E2 due to neonatal ovariectomy (OVX). All females were then perfused at the time of the expected surge and brains processed for estrogen receptor and Fos immunoreactivity. None of the T females exposed postnatally to E2 exhibited an E2-induced LH surge, but a surge was produced in five of six T/OVX and all Control females. No surges were produced when progesterone was administered concomitantly with E2. All Control females were mounted by males, but significantly fewer T females were mounted by a male, including the T/OVX females that exhibited LH surges. The percentage of estrogen receptor neurons containing Fos was significantly influenced in a brain region-, developmental stage-, and steroid-specific fashion by testosterone and E2 treatments. These findings support the hypothesis that the feedback controls of the GnRH surge are sensitive to programming by prenatal and postnatal steroids in a precocial species. PMID:23417422

View of Stand Pipe (Surge Tank) from FS 502. Looking ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

View of Stand Pipe (Surge Tank) from FS 502. Looking northeast - Childs-Irving Hydroelectric Project, Childs System, Stand Pipe (Surge Tank), Forest Service Road 708/502, Camp Verde, Yavapai County, AZ

From cyclic ice streaming to Heinrich-like events: the grow-and-surge instability in the Parallel Ice Sheet Model

NASA Astrophysics Data System (ADS)

Feldmann, Johannes; Levermann, Anders

2017-08-01

Here we report on a cyclic, physical ice-discharge instability in the Parallel Ice Sheet Model, simulating the flow of a three-dimensional, inherently buttressed ice-sheet-shelf system which periodically surges on a millennial timescale. The thermomechanically coupled model on 1 km horizontal resolution includes an enthalpy-based formulation of the thermodynamics, a nonlinear stress-balance-based sliding law and a very simple subglacial hydrology. The simulated unforced surging is characterized by rapid ice streaming through a bed trough, resulting in abrupt discharge of ice across the grounding line which is eventually calved into the ocean. We visualize the central feedbacks that dominate the subsequent phases of ice buildup, surge and stabilization which emerge from the interaction between ice dynamics, thermodynamics and the subglacial till layer. Results from the variation of surface mass balance and basal roughness suggest that ice sheets of medium thickness may be more susceptible to surging than relatively thin or thick ones for which the surge feedback loop is damped. We also investigate the influence of different basal sliding laws (ranging from purely plastic to nonlinear to linear) on possible surging. The presented mechanisms underlying our simulations of self-maintained, periodic ice growth and destabilization may play a role in large-scale ice-sheet surging, such as the surging of the Laurentide Ice Sheet, which is associated with Heinrich events, and ice-stream shutdown and reactivation, such as observed in the Siple Coast region of West Antarctica.

Comparison of occlusion break responses and vacuum rise times of phacoemulsification systems.

PubMed

Sharif-Kashani, Pooria; Fanney, Douglas; Injev, Val

2014-07-30

Occlusion break surge during phacoemulsification cataract surgery can lead to potential surgical complications. The purpose of this study was to quantify occlusion break surge and vacuum rise time of current phacoemulsification systems used in cataract surgery. Occlusion break surge at vacuum pressures between 200 and 600 mmHg was assessed with the Infiniti® Vision System, the WhiteStar Signature® Phacoemulsification System, and the Centurion® Vision System using gravity-fed fluidics. Centurion Active FluidicsTM were also tested at multiple intraoperative pressure target settings. Vacuum rise time was evaluated for Infiniti, WhiteStar Signature, Centurion, and Stellaris® Vision Enhancement systems. Rise time to vacuum limits of 400 and 600 mmHg was assessed at flow rates of 30 and 60 cc/minute. Occlusion break surge was analyzed by 2-way analysis of variance. The Centurion system exhibited substantially less occlusion break surge than the other systems tested. Surge area with Centurion Active Fluidics was similar to gravity fluidics at an equivalent bottle height. At all Centurion Active Fluidics intraoperative pressure target settings tested, surge was smaller than with Infiniti and WhiteStar Signature. Infiniti had the fastest vacuum rise time and Stellaris had the slowest. No system tested reached the 600-mmHg vacuum limit. In this laboratory study, Centurion had the least occlusion break surge and similar vacuum rise times compared with the other systems tested. Reducing occlusion break surge may increase safety of phacoemulsification cataract surgery.

Comparison of occlusion break responses and vacuum rise times of phacoemulsification systems

PubMed Central

2014-01-01

Background Occlusion break surge during phacoemulsification cataract surgery can lead to potential surgical complications. The purpose of this study was to quantify occlusion break surge and vacuum rise time of current phacoemulsification systems used in cataract surgery. Methods Occlusion break surge at vacuum pressures between 200 and 600 mmHg was assessed with the Infiniti® Vision System, the WhiteStar Signature® Phacoemulsification System, and the Centurion® Vision System using gravity-fed fluidics. Centurion Active FluidicsTM were also tested at multiple intraoperative pressure target settings. Vacuum rise time was evaluated for Infiniti, WhiteStar Signature, Centurion, and Stellaris® Vision Enhancement systems. Rise time to vacuum limits of 400 and 600 mmHg was assessed at flow rates of 30 and 60 cc/minute. Occlusion break surge was analyzed by 2-way analysis of variance. Results The Centurion system exhibited substantially less occlusion break surge than the other systems tested. Surge area with Centurion Active Fluidics was similar to gravity fluidics at an equivalent bottle height. At all Centurion Active Fluidics intraoperative pressure target settings tested, surge was smaller than with Infiniti and WhiteStar Signature. Infiniti had the fastest vacuum rise time and Stellaris had the slowest. No system tested reached the 600-mmHg vacuum limit. Conclusions In this laboratory study, Centurion had the least occlusion break surge and similar vacuum rise times compared with the other systems tested. Reducing occlusion break surge may increase safety of phacoemulsification cataract surgery. PMID:25074069

Soil and groundwater attenuation factors for nitrogen from septic systems in the Chesapeake Bay TMDL

NASA Astrophysics Data System (ADS)

Radcliffe, D. E.; Geza, M.; O'Drisoll, M.; Humphrey, C., Jr.

2015-12-01

An expert panel was tasked with estimating the percent of the nitrogen (N) load from septic systems that was lost in the flow path from a typical home to third-order streams as part of the Chesapeake Bay Total Maximum Daily Load (TMDL). These losses were referred to as attenuation factors. We developed values for the soil (unsaturated) zone and for the Piedmont and Coastal Plain groundwater zones. For the soil zone, we used the Soil Treatment Unit MODel (STUMOD) to estimate loses due to denitrification for all 12 soil textural classes and then averaged the results over three textural groups. Assuming hydraulic loading at the design rate and a conventional system, the attenuation factors were 16% for sand, loamy sand, sandy loam, and loam soils; 34% for silt loam, clay loam, sandy clay loam, silty clay loam, and silt soils; and 54% for sandy clay, silty clay, and clay soils. Attenuation factors increased in the more clayey soils due to wetter conditions and more losses due to denitrification. Attenuation factors were also developed for reduced hydraulic loading rates and for systems using advanced N pre-treatment. For the Piedmont groundwater zone, we used data from a recent study in Georgia of small suburban streams with high-density septic systems. Stream base-flow load was estimated using simultaneous measurements of total N concentration and discharge and compared to the estimated groundwater input load, resulting in an attenuation factor of 81%. For the Coastal Plain groundwater zone, literature values of groundwater N concentrations within septic system plumes in Virginia, North Carolina, and Florida were used to estimate an attenuation factor of approximately 60% at 100m downgradient from the drainfield. These attenuation factors will be used to estimate the contribution of N to the Chesapeake Bay in the Phase 6 TMDL models.

Storm Surge Simulation and Ensemble Forecast for Hurricane Irene (2011)

NASA Astrophysics Data System (ADS)

Lin, N.; Emanuel, K.

2012-12-01

Hurricane Irene, raking the U.S. East Coast during the period of 26-30 August 2011, caused widespread damage estimated at $15.8 billion and was responsible for 49 direct deaths (Avila and Cangialosi, 2011). Although the most severe impact in the northeastern U.S. was catastrophic inland flooding, with its unusually large size, Irene also generated high waves and storm surges and caused moderate to major coastal flooding. The most severe surge damage occurred between Oregon Inlet and Cape Hatteras in North Carolina (NC). Significant storm surge damage also occurred along southern Chesapeake Bay, and moderate and high surges were observed along the coast from New Jersey (NJ) northward. A storm surge of 0.9-1.8 m caused hundreds of millions of dollars in property damage in New York City (NYC) and Long Island, despite the fact that the storm made landfall to the west of NYC with peak winds of no more than tropical storm strength. Making three U.S. landfalls (in NC, NJ, and NY), Hurricane Irene provides a unique case for studying storm surge along the eastern U.S. coastline. We apply the hydrodynamic model ADCIRC (Luettich et al. 1992) to conduct surge simulations for Pamlico Sound, Chesapeake Bay, and NYC, using best track data and parametric wind and pressure models. The results agree well with tidal-gauge observations. Then we explore a new methodology for storm surge ensemble forecasting and apply it to Irene. This method applies a statistical/deterministic hurricane model (Emanuel et al. 2006) to generate large numbers of storm ensembles under the storm environment described by the 51 ECMWF ensemble members. The associated surge ensembles are then generated with the ADCIRC model. The numerical simulation is computationally efficient, making the method applicable to real-time storm surge ensemble forecasting. We report the results for NYC in this presentation. The ADCIRC simulation using the best track data generates a storm surge of 1.3 m and a storm tide of 2.1 m at the Battery, NYC, which agree well with the observed storm surge of 1.33 m and storm tide of 2.12 m, although the simulated surge arrives about 2 hours earlier than the observed. Based on the surge climatology estimated by Lin et al. (2012), Hurricane Irene's storm surge is approximately a 60-year event for NYC, but its storm tide, with the surge happening right at the high astronomical tide, is a 100-year event. Lin et al. (2012) also projected that such 100-year storm tide events might occur on average every 3-20 years by the end of the century, under the IPCC A1B emission scenario and a 1-m sea level rise. The ensemble forecasting, starting from two and one days (each with 1000 ensembles) before Irene's first landfall in NC, shows that Irene's actual storm surge at the Battery had a chance of about 9% and 10% to be exceeded, respectively. The largest surges among the two ensemble sets are 2.28 m and 2.05 m, respectively. If happening at the high tide, as with Hurricane Irene, the worst-case storm tides would be about 3-3.2 m, similar to the highest historical water level at the Battery due to a hurricane in 1821. Lin et al. (2012) estimated that such a storm tide of about 3.1 m had a return period of about 500 years under current climate conditions, but the return period might become 25-240 years by the end of the century, under the IPCC A1B emission scenario and a 1-m sea level rise.

Effect of bottle height and aspiration rate on postocclusion surge in Infiniti and Millennium peristaltic phacoemulsification machines.

PubMed

Ward, Matthew S; Georgescu, Dan; Olson, Randall J

2008-08-01

To assess how flow and bottle height affect postocclusion surge in the Infiniti (Alcon, Inc.) and Millennium (Bausch & Lomb) peristaltic machines. John A. Moran Eye Center Clinical Laboratories, University of Utah, Salt Lake City, Utah. Postocclusion anterior chamber depth changes were measured in human eye-bank eyes using A-scan. Surge was simulated by clamping the aspiration tubing and releasing it at maximum vacuum. In both machines, surge was measured (1) with aspiration held constant at 12 mL/min and bottle heights at 60, 120, and 180 cm and (2) with bottle height held constant at 60 cm and aspiration rates at 12, 24, and 36 mL/min. Surge decreased approximately 40% with each 60 cm increase in bottle height in the Infiniti. It was constant at all bottle heights in the Millennium. At 12 and 24 mL/min aspiration rates, surge in the Millennium was less than half that in the Infiniti (P<.001). Postocclusion surge decreased linearly with increasing bottle height in the Infiniti system and was relatively constant with increasing bottle height in the Millennium system. The Millennium may offer a more stable phacoemulsification platform with respect to surge at a higher aspiration rate.

Effects of Hurricane Katrina’s storm surge on the quality of shallow aquifers near the northern shoreline of Lake Pontchartrain, southeastern Louisiana: Chapter 7D in Science and the storms-the USGS response to the hurricanes of 2005

USGS Publications Warehouse

Tomaszewski, Dan J.; Lovelace, John K.

2007-01-01

The U.S. Geological Survey (USGS) sampled 13 wells on the northern shoreline of Lake Pontchartrain to determine the effect of Hurricane Katrina-induced storm surge water on the shallow groundwater resources. Surge water entering damaged wells did not contaminate the entire aquifer; however, contamination did occur locally at well sites. Because the storm surge from Katrina lasted only a few hours, surge water entering the aquifer will probably have only a short-term effect.

Atheroprotection through SYK inhibition fails in established disease when local macrophage proliferation dominates lesion progression.

PubMed

Lindau, Alexandra; Härdtner, Carmen; Hergeth, Sonja P; Blanz, Kelly Daryll; Dufner, Bianca; Hoppe, Natalie; Anto-Michel, Nathaly; Kornemann, Jan; Zou, Jiadai; Gerhardt, Louisa M S; Heidt, Timo; Willecke, Florian; Geis, Serjosha; Stachon, Peter; Wolf, Dennis; Libby, Peter; Swirski, Filip K; Robbins, Clinton S; McPheat, William; Hawley, Shaun; Braddock, Martin; Gilsbach, Ralf; Hein, Lutz; von zur Mühlen, Constantin; Bode, Christoph; Zirlik, Andreas; Hilgendorf, Ingo

2016-03-01

Macrophages in the arterial intima sustain chronic inflammation during atherogenesis. Under hypercholesterolemic conditions murine Ly6C(high) monocytes surge in the blood and spleen, infiltrate nascent atherosclerotic plaques, and differentiate into macrophages that proliferate locally as disease progresses. Spleen tyrosine kinase (SYK) may participate in downstream signaling of various receptors that mediate these processes. We tested the effect of the SYK inhibitor fostamatinib on hypercholesterolemia-associated myelopoiesis and plaque formation in Apoe(-/-) mice during early and established atherosclerosis. Mice consuming a high cholesterol diet supplemented with fostamatinib for 8 weeks developed less atherosclerosis. Histologic and flow cytometric analysis of aortic tissue showed that fostamatinib reduced the content of Ly6C(high) monocytes and macrophages. SYK inhibition limited Ly6C(high) monocytosis through interference with GM-CSF/IL-3 stimulated myelopoiesis, attenuated cell adhesion to the intimal surface, and blocked M-CSF stimulated monocyte to macrophage differentiation. In Apoe(-/-) mice with established atherosclerosis, however, fostamatinib treatment did not limit macrophage accumulation or lesion progression despite a significant reduction in blood monocyte counts, as lesional macrophages continued to proliferate. Thus, inhibition of hypercholesterolemia-associated monocytosis, monocyte infiltration, and differentiation by SYK antagonism attenuates early atherogenesis but not established disease when local macrophage proliferation dominates lesion progression.

Bacteria and genetically modified bacteria as cancer therapeutics: Current advances and challenges.

PubMed

Nallar, Shreeram C; Xu, De-Qi; Kalvakolanu, Dhan V

2017-01-01

Bacteria act as pro- or anti- tumorigenic agents. Whole bacteria or cytotoxic or immunogenic peptides carried by them exert potent anti-tumor effects in the experimental models of cancer. The use of attenuated microorganism(s) e.g., BCG to treat human urinary bladder cancer was found to be superior compared to standard chemotherapy. Although the phase-I clinical trials with Salmonella enterica serovar Typhimurium, has shown limited benefits in human subjects, a recent pre-clinical trial in pet dogs with tumors reported some subjects benefited from this treatment strain. In addition to the attenuated host strains derived by conventional mutagenesis, recombinant DNA technology has been applied to a few microorganisms that have been evaluated in the context of tumor colonization and eradication using mouse models. There is an enormous surge in publications describing bacterial anti-cancer therapies in the past 15years. Vectors for delivering shRNAs that target oncogenic products, express tumor suppressor genes and immunogenic proteins have been developed. These approaches have showed promising anti-tumor activity in mouse models against various tumors. These can be potential therapeutics for humans in the future. In this review, some conceptual and practical issues on how to improve these agents for human applications are discussed. Copyright © 2016. Published by Elsevier Ltd.

Surging glaciers in Iceland - research status and future challenges

NASA Astrophysics Data System (ADS)

Ingolfsson, Olafur

2013-04-01

Twenty six Icelandic outlet glaciers, ranging from 0.5-1.500 km2, are known to surge, with terminal advances ranging from of few tens of meters to about 10 km. The geomorphic signatures of surges vary, from large-scale folded and thrusted end moraine systems, extensive dead-ice fields and drumlinized forefields to drift sheets where fast ice-flow indicators are largely missing. Case studies from the forefields of Brúarjökull, Eyjabakkajökull and Múlajökull surging glaciers will be presented. At Brúarjökull, extremely rapid ice flow during surge was sustained by overpressurized water causing decoupling beneath a thick sediment sequence that was coupled to the glacier. The ice-marginal position of the 1890 surge is marked by a sedimentary wedge formed within five days and a large moraine ridge that formed in about one day ("instantaneous end-moraine"). Three different qualitative and conceptual models are required to explain the genesis of the Eyjabakkajökull moraines: a narrow, single-crested moraine ridge at the distal end of a marginal sediment wedge formed in response to decoupling of the subglacial sediment from the bedrock and associated downglacier sediment transport; large lobate end moraine ridges with multiple, closely spaced, asymmetric crests formed by proglacial piggy-back thrusting; moraine ridges with different morphologies may reflect different members of an end moraine continuum. A parallel study highlighting the surge history of Eyjabakkajökull over the last 4400 years suggests climate control on surge frequencies. The Múlajökull studies concern an active drumlin field (>100 drumlins) that is being exposed as the glacier retreats. The drumlins form through repeated surges, where each surge causes deposition of till bed onto the drumlin while similtaneously eroding the sides. Finally, a new landsystem model for surging North Iceland cirque glaciers will be introduced. References Benediktsson,I. Ö., Schomacker, A., Lokrantz, H. & Ingólfsson, Ó. 2010: The 1890 surge end moraine at Eyjabakkajökull, Iceland: a re-assessment of a classic glaciotectonic locality. Quaternary Science Reviews 29, 484-506. Benediktsson, I.Ö., Ingólfsson, Ó., Schomacker, A. & Kjær, K.H. 2009: Formation of sub-marginal and proglacial end moraines: implications of ice-flow mechanism during the 1963-64 surge of Brúarjökull, Iceland. Boreas 38. 440-457. Benediktsson, Í.Ö., Möller, P., Ingólfsson, Ó., van der Meer, J.J.M., Kjær, K. & Krüger, J. 2008: Instantaneous end moraine and sediment wedge formation during the 1890 glacier surge of Brúarjökull, Iceland. Quaternary Science Reviews 27, 209-234. Brynjólfsson, S., Ingólfsson, Ó. & Schomacker, A. 2012. Surge fingerprinting of cirque glaciers at the Tröllaskagi peninsula, Iceland. Jökull 62, 153-168. Johnson, M.D., Schomacker, A.,Benediktsson, I.O., Geiger, A.D., Ferguson, A. & Ingólfsson, Ó. 2010. Active drumlin field revealed at the margin of Múlajökull, Iceland: A surge-type glacier. Geology 38, 943-946. Kjær, K.H., Larsen, E., van der Meer, J., Ingólfsson, Ó., Krüger, J., Benediktsson, I.Ö., Knudsen, C. & Schumacher, A. 2006: Subglacial decoupling at the sediment/bedrock interface: a new mechanism for rapid flowing ice. Quaternary Science Reviews, 25: 2704-2712. Striberger, J., Björck, S., Benediktsson, I.Ö., Snowball. I., Uvo, C., Ingólfsson, Ó. & Kjær, K. 2011. Climatic control of the surge periodicity of an Icelandic outlet glacier. Journal of Quaternary Science 26, 561-565.

The communications industry's requirements and interests. [thunderstorm and lightning data useful to telephone operating companies

NASA Technical Reports Server (NTRS)

Wanaselja, O.

1979-01-01

Of interest to the communications industry are the amplitude, waveshape, duration and frequency of lightning-originated voltage surges and transients on the communications network, including the distribution system and AC power supply circuits. The cloud-to-ground lightning discharge and its characteristics are thought to be most meaningful. Of specific interest are peak current, waveshape, number of flashes, strokes per flash, and zone of influence. Accurate and meaningful lightning data at the local level (telephone district office) is necessary for a decision on the appropriate protection level. In addition to lightning, the protection engineer must consider other factors such as: AC induction, switching surges, ground potential rise, soil resistivity, bonding and grounding techniques, shielding and isolation, and exposure of the telephone loop.

BAX inhibitor-1 is a Ca2+ channel critically important for immune cell function and survival

PubMed Central

Lisak, D; Schacht, T; Gawlitza, A; Albrecht, P; Aktas, O; Koop, B; Gliem, M; Hofstetter, H H; Zanger, K; Bultynck, G; Parys, J B; De Smedt, H; Kindler, T; Adams-Quack, P; Hahn, M; Waisman, A; Reed, J C; Hövelmeyer, N; Methner, A

2016-01-01

The endoplasmic reticulum (ER) serves as the major intracellular Ca2+ store and has a role in the synthesis and folding of proteins. BAX (BCL2-associated X protein) inhibitor-1 (BI-1) is a Ca2+ leak channel also implicated in the response against protein misfolding, thereby connecting the Ca2+ store and protein-folding functions of the ER. We found that BI-1-deficient mice suffer from leukopenia and erythrocytosis, have an increased number of splenic marginal zone B cells and higher abundance and nuclear translocation of NF-κB (nuclear factor-κ light-chain enhancer of activated B cells) proteins, correlating with increased cytosolic and ER Ca2+ levels. When put into culture, purified knockout T cells and even more so B cells die spontaneously. This is preceded by increased activity of the mitochondrial initiator caspase-9 and correlated with a significant surge in mitochondrial Ca2+ levels, suggesting an exhausted mitochondrial Ca2+ buffer capacity as the underlying cause for cell death in vitro. In vivo, T-cell-dependent experimental autoimmune encephalomyelitis and B-cell-dependent antibody production are attenuated, corroborating the ex vivo results. These results suggest that BI-1 has a major role in the functioning of the adaptive immune system by regulating intracellular Ca2+ homeostasis in lymphocytes. PMID:26470731

Effect of Hydraulic Accumulator on Pressure Surge of a Hydrostatic Transmission System

NASA Astrophysics Data System (ADS)

Kumar, Ajit; Das, Jayanta; Dasgupta, Kabir; Barnwal, Manish Kumar

2018-04-01

Hydraulic power system is generally used in off-road vehicles for power transmission such as Heavy Earth Moving Machineries (HEMM). Their energy efficiency and unsubstantial failure becomes an extensive subject of analysis. Various arrangements in the system are compassed along with the utilization of some appropriate components. Application of a hydraulic accumulator is one among them. Benefits of accumulator is its multi-purpose usages like energy saving and pressure surge damping. This paper deals with the control of pressure surges in the hydraulic system and energy saving from the surges by using accumulator. For this purpose, the simulation of the hydraulic system is done in MATLAB/SimulinkR environment and an external disturbance is introduced to generate the pressure surge. The surge absorptivity of the accumulator is studied for different sizes at different pre-charged conditions of the accumulator. The discharge characteristics of different sized accumulators are also analyzed in this paper. It is observed that the ability to absorb the surge and stabilize the system is high in the smaller capacity accumulator. However the energy delivery time of larger sized accumulator is high.

A numerical study of wave-current interaction through surface and bottom stresses: Coastal ocean response to Hurricane Fran of 1996

NASA Astrophysics Data System (ADS)

Xie, L.; Pietrafesa, L. J.; Wu, K.

2003-02-01

A three-dimensional wave-current coupled modeling system is used to examine the influence of waves on coastal currents and sea level. This coupled modeling system consists of the wave model-WAM (Cycle 4) and the Princeton Ocean Model (POM). The results from this study show that it is important to incorporate surface wave effects into coastal storm surge and circulation models. Specifically, we find that (1) storm surge models without coupled surface waves generally under estimate not only the peak surge but also the coastal water level drop which can also cause substantial impact on the coastal environment, (2) introducing wave-induced surface stress effect into storm surge models can significantly improve storm surge prediction, (3) incorporating wave-induced bottom stress into the coupled wave-current model further improves storm surge prediction, and (4) calibration of the wave module according to minimum error in significant wave height does not necessarily result in an optimum wave module in a wave-current coupled system for current and storm surge prediction.

Improvement of Surge Protection by Using an AlGaN/GaN-Based Metal-Semiconductor-Metal Two-Dimensional Electron Gas Varactor

NASA Astrophysics Data System (ADS)

Ferng, Yi-Cherng; Chang, Liann-Be; Das, Atanu; Lin, Ching-Chi; Cheng, Chun-Yu; Kuei, Ping-Yu; Chow, Lee

2012-12-01

In this paper, a varactor with metal-semiconductor-metal diodes on top of the (NH4)2S/P2S5-treated AlGaN/GaN two-dimensional electron gas epitaxial structure (MSM-2DEG) is proposed to the surge protection for the first time. The sulfur-treated MSM-2DEG varactor properties, including current-voltage (I-V), capacitance-voltage (C-V), and frequency response of the proposed surge protection circuit, are presented. To verify its capability of surge protection, we replace the metal oxide varistor (MOV) and resistor (R) in a state-of-the-art surge protection circuit with the sulfur-treated MSM-2DEG varactor under the application conditions of system-level surge tests. The measured results show that the proposed surge protection circuit, consisted of a gas discharge arrester (GDA) and a sulfur-treated MSM-2DEG varactor, can suppress an electromagnetic pulse (EMP) voltage of 4000 to 360 V, a reduction of 91%, whereas suppression is to 1780 V, a reduction of 55%, when using only a GDA.

Atlantic hurricane surge response to geoengineering.

PubMed

Moore, John C; Grinsted, Aslak; Guo, Xiaoran; Yu, Xiaoyong; Jevrejeva, Svetlana; Rinke, Annette; Cui, Xuefeng; Kravitz, Ben; Lenton, Andrew; Watanabe, Shingo; Ji, Duoying

2015-11-10

Devastating floods due to Atlantic hurricanes are relatively rare events. However, the frequency of the most intense storms is likely to increase with rises in sea surface temperatures. Geoengineering by stratospheric sulfate aerosol injection cools the tropics relative to the polar regions, including the hurricane Main Development Region in the Atlantic, suggesting that geoengineering may mitigate hurricanes. We examine this hypothesis using eight earth system model simulations of climate under the Geoengineering Model Intercomparison Project (GeoMIP) G3 and G4 schemes that use stratospheric aerosols to reduce the radiative forcing under the Representative Concentration Pathway (RCP) 4.5 scenario. Global mean temperature increases are greatly ameliorated by geoengineering, and tropical temperature increases are at most half of those temperature increases in the RCP4.5. However, sulfate injection would have to double (to nearly 10 teragrams of SO2 per year) between 2020 and 2070 to balance the RCP4.5, approximately the equivalent of a 1991 Pinatubo eruption every 2 y, with consequent implications for stratospheric ozone. We project changes in storm frequencies using a temperature-dependent generalized extreme value statistical model calibrated by historical storm surges and observed temperatures since 1923. The number of storm surge events as big as the one caused by the 2005 Katrina hurricane are reduced by about 50% compared with no geoengineering, but this reduction is only marginally statistically significant. Nevertheless, when sea level rise differences in 2070 between the RCP4.5 and geoengineering are factored into coastal flood risk, we find that expected flood levels are reduced by about 40 cm for 5-y events and about halved for 50-y surges.

Cold basal conditions during surges control flow of fringing Arctic ice caps in Greenland

NASA Astrophysics Data System (ADS)

Cook, Samuel; Christoffersen, Poul; Todd, Joe; Palmer, Steven

2017-04-01

Fringing ice caps separated from larger ice sheets are rarely studied, yet they are an important part of earth's cryosphere, which has become the largest source of global sea-level rise. Understanding marginal ice caps is crucial for being able to predict sea-level change as they are responsible for up to 20% of Greenland's mass loss for 2003-2008. Studies of fringing ice caps can furthermore provide useful insights into processes operating on glaciers that surge. Surging has been the focus of much recent glaciological work, especially with reference to thermal evolution of polythermal glaciers in High Mountain Asia and the High Arctic. This has shown that the classic divide between hydrologically-controlled surges ('hard-bed') in Alaska and thermally-regulated ('soft-bed') surges elsewhere is less stark than previously assumed. Studying marginal ice caps can therefore be valuable in several ways. The largest fringing ice cap in Greenland is Flade Isblink. Previous work has established that this ice cap is showing a range of dynamic behaviour, including subglacial lake drainage and varied patterns of mass-balance change. In particular, a substantial surge, assumed to be caused by a version of the thermally-regulated mechanism, occurred between 1996 and 2000, making the ice cap a useful case study for investigating this process. Here we investigate the surge on Flade Isblink using the open-source, Full-Stokes model Elmer/Ice to invert for basal conditions and englacial temperatures using the adjoint method. We specifically study steady-state conditions representative of the active surge phase in 2000, and the subsequent quiescent phase, using patterns of surface velocity observed in 2000, 2005, 2008 and 2015. Under constant geometry, temperature and geothermal heat, it is shown that surging increases basal freezing rates by over 60% across an area that is twice as large as the area over which the bed freezes in the quiescent phase. The process responsible for this is the conductive heat loss, which increases faster than frictional heat is produced. When the bed becomes weaker, basal conditions become colder despite faster basal sliding, resulting in steep basal ice temperature gradients, which transfer heat effectively from the bed into the ice. In contrast, we find the increase in frictional heat to be insufficient, because weaker basal conditions offset the effect of faster basal sliding. Hence, frictional heat cannot provide enough extra melting to maintain surge conditions. We hypothesise that this heat transfer mechanism terminates surges on Flade Isblink, irrespective of any thinning that would also occur. The latter is not included in our model, but is required in the classic soft-bed surge model. In the quiescent phase, lower temperature gradients reduce the conductive heat loss, while a stronger bed produces more frictional heat, favouring basal melting and a warm bed, which ultimately create the weak basal conditions that result in yet another surge, regardless of any change in ice thickness. Our results indicate that soft-bed surges may occur even if the surge-related change in glacier geometry is modest, making surging glaciers of this type similar to ice streams that stagnate and reactivate periodically.

Experiments and modelling of surge in small centrifugal compressor for automotive engines

DOE Office of Scientific and Technical Information (OSTI.GOV)

Galindo, J.; Serrano, J.R.; Climent, H.

2008-01-15

In this paper the surge phenomenon in small centrifugal compressors used for turbocharging internal combustion engines is analyzed. The experimental work was focused on the measurement of compressor behaviour within the surge zone by means of a specifically designed facility. The presented model is based on the introduction of a fluid inertia term that accounts for the non quasi steady effects and the use of a compressor map extended to the surge and negative flows zone obtained from experimental tests. The compressor model was implemented in a one-dimensional gas-dynamic model. The comparison of the modelled and measured evolution of instantaneousmore » pressure during deep surge operation shows good agreement. Furthermore, the model is also able to predict the amplitude and frequency of pressure pulses when the compressor operates in surge with different outlet duct lengths. (author)« less

Local amplification of storm surge by Super Typhoon Haiyan in Leyte Gulf.

PubMed

Mori, Nobuhito; Kato, Masaya; Kim, Sooyoul; Mase, Hajime; Shibutani, Yoko; Takemi, Tetsuya; Tsuboki, Kazuhisa; Yasuda, Tomohiro

2014-07-28

Typhoon Haiyan, which struck the Philippines in November 2013, was an extremely intense tropical cyclone that had a catastrophic impact. The minimum central pressure of Typhoon Haiyan was 895 hPa, making it the strongest typhoon to make landfall on a major island in the western North Pacific Ocean. The characteristics of Typhoon Haiyan and its related storm surge are estimated by numerical experiments using numerical weather prediction models and a storm surge model. Based on the analysis of best hindcast results, the storm surge level was 5-6 m and local amplification of water surface elevation due to seiche was found to be significant inside Leyte Gulf. The numerical experiments show the coherent structure of the storm surge profile due to the specific bathymetry of Leyte Gulf and the Philippines Trench as a major contributor to the disaster in Tacloban. The numerical results also indicated the sensitivity of storm surge forecast.

Progression of the 2011-2012 Surge of Bering Glacier and Bagley Ice Field, Alaska

NASA Astrophysics Data System (ADS)

Herzfeld, U. C.; McDonald, B.; Stachura, M.; Hale, R.; Trantow, T.; Weltman, A.; Chen, P.

2012-12-01

Bering Glacier, Alaska, started a surge in late spring 2011. The surge reached the ice front in May 2011 and extended into Bagley Ice Field by summer 2011. New surge-related crevassing was observed in July 2012. We collected aerial observations, including systematic videographic and photographic imagery, GPS data and laser altimeter data in September 2011 and in July 2012. In this talk, an analysis of surge progression and comparison to the early, mature and late stages of the 1993-1995 surge of Bering Glacier and Bagley Ice Field will be presented. A suite of approaches will be used to this end: Analysis of elevation changes based on CryoSat data, 2009 and 2010 IceBridge data and 2011 and 2012 laser altimeter data collected by our group, geostatistical classification of crevasse types based on imagery, classification of laser altimeter data and analysis of high-resolution satellite imagery (Worldview and GEOS).

A surge observed in H alpha and C IV

NASA Technical Reports Server (NTRS)

Schmieder, B.; Mein, P.; Vial, J. C.; Tandberg-Hanssen, E.

1982-01-01

Results are presented of simultaneous measurements of H-alpha (MSDP at Meudon) and C IV (UVSP onboard SMM) of Active Region 2701 made on October 2, 1980. Isodensity and velocity maps were obtained for both lines and these maps were superimposed. Results show a good correlation between the H-alpha and C IV velocities with a surge being observed for 10 minutes. The base of the surge was determined to be located in a bright point in C IV and H-alpha, while the escaping matter followed the same channel ('absorbing' in H-alpha, 'emitting' in C IV). It was found that the velocity along the surge was about 80 km/s in H-alpha and 100 km/s in C IV. In addition, a loop appeared in C IV during the surge. It is concluded that the vertical pressure gradient was capable of driving the surge.

Planning for a medical surge incident: Is rehabilitation the missing link?

PubMed

Vonderschmidt, Kay

2017-01-01

This mixed methods study explored surge planning for patients who will need rehabilitative care after a mass casualty incident. Planning for a patient surge incident typically considers only prehospital and hospital care. However, in many cases, disaster patients need rehabilitation for which planning is often overlooked. The purpose of this study was to explore this hidden dimension of patient rehabilitation for surge planning and preparedness and ask: 1. To what extent can an analysis of standard patient acuity assessment tools [Simple Triage and Rapid Treatment and Injury Severity Score] be used to project future demand for admission to rehabilitative care? 2. What improvements to medical disaster planning are needed to address patient surge related to rehabilitation? This study found that standard patient benchmarks can be used to project demand for rehabilitation following a mass casualty incident, and argues that a reconceptualization of surge planning to include rehabilitation would improve medical disaster planning.

Anomalous Surge of the White-Light Corona at the Onset of the Declining Phase of Solar Cycle 24

NASA Astrophysics Data System (ADS)

Lamy, P.

2017-12-01

In late 2014, when the current solar cycle 24 was initiating its declining phase, the white-light corona as observed by the LASCO-C2 coronagraph underwent an unexpected surge that increased its global radiance by 60%, reaching a peak value comparable to those of the more active solar cycle 23. The daily variations point to a localized enhancement or bulge in the electron density that persisted during several months. Carrington maps of the radiance and of the HMI photospheric field allow connecting this bulge to the emergence of the large sunspot complex AR 12192 in October 2014, the largest since AR 6368 observed in November 1990. The resulting unusually large increase of the magnetic field and the distortion of the neutral sheet in a characteristic inverse S-shape caused the coronal plasma to be trapped along a similar pattern. Three-dimensional reconstruction of the electron density based on time-dependent solar rotational tomography supplemented by 2D inversion of the coronal radiance confirms the morphology of the bulge and reveals that its level was well above the standard models of a corona of the maximum type, by typically a factor of 3. A rather satisfactory agreement is found with the results of the thermodynamic MHD model produced by Predictive Sciences although discrepancies are noted. The specific configuration of the magnetic field that led to the coronal surge resulted from the interplay of various factors prevailing at the onset of the declining phase of the solar cycles which was particularly efficient in the case of solar cycle 24.

A synoptic and dynamical characterization of wave-train and blocking cold surge over East Asia

NASA Astrophysics Data System (ADS)

Park, Tae-Won; Ho, Chang-Hoi; Deng, Yi

2014-08-01

Through an agglomerative hierarchical clustering method, cold surges over East Asia are classified into two distinct types based on the spatial pattern of the geopotential height anomalies at 300 hPa. One is the wave-train type that is associated with developing large-scale waves across the Eurasian continent. The other is the blocking type whose occurrence accompanies subarctic blocking. During the wave-train cold surge, growing baroclinic waves induce a southeastward expansion of the Siberian High and strong northerly winds over East Asia. Blocking cold surge, on the other hand, is associated with a southward expansion of the Siberian High and northeasterly winds inherent to a height dipole consisting of the subarctic blocking and the East Asian coastal trough. The blocking cold surge tends to be more intense and last longer compared to the wave-train type. The wave-train cold surge is associated with the formation of a negative upper tropospheric height anomaly southeast of Greenland approximately 12 days before the surge occurrence. Further analysis of isentropic potential vorticity reveals that this height anomaly could originate from the lower stratosphere over the North Atlantic. Cold surge of the blocking type occurs with an amplifying positive geopotential and a negative potential vorticity anomaly over the Arctic and the northern Eurasia in stratosphere. These anomalies resemble the stratospheric signature of a negative phase of the Arctic Oscillation. This stratospheric feature is further demonstrated by the observation that the blocking type cold surge occurs more often when the Arctic Oscillation is in its negative phase.

Surges and Si IV Bursts in the Solar Atmosphere: Understanding IRIS and SST Observations through RMHD Experiments

NASA Astrophysics Data System (ADS)

Nóbrega-Siverio, D.; Martínez-Sykora, J.; Moreno-Insertis, F.; Rouppe van der Voort, L.

2017-12-01

Surges often appear as a result of the emergence of magnetized plasma from the solar interior. Traditionally, they are observed in chromospheric lines such as Hα 6563 \\mathringA and Ca II 8542 \\mathringA . However, whether there is a response to the surge appearance and evolution in the Si IV lines or, in fact, in many other transition region lines has not been studied. In this paper, we analyze a simultaneous episode of an Hα surge and a Si IV burst that occurred on 2016 September 03 in active region AR 12585. To that end, we use coordinated observations from the Interface Region Imaging Spectrograph and the Swedish 1-m Solar Telescope. For the first time, we report emission of Si IV within the surge, finding profiles that are brighter and broader than the average. Furthermore, the brightest Si IV patches within the domain of the surge are located mainly near its footpoints. To understand the relation between the surges and the emission in transition region lines like Si IV, we have carried out 2.5D radiative MHD (RMHD) experiments of magnetic flux emergence episodes using the Bifrost code and including the nonequilibrium ionization of silicon. Through spectral synthesis, we explain several features of the observations. We show that the presence of Si IV emission patches within the surge, their location near the surge footpoints and various observed spectral features are a natural consequence of the emergence of magnetized plasma from the interior to the atmosphere and the ensuing reconnection processes.

Different critical perinatal periods and hypothalamic sites of oestradiol action in the defeminisation of luteinising hormone surge and lordosis capacity in the rat.

PubMed

Sakakibara, M; Deura, C; Minabe, S; Iwata, Y; Uenoyama, Y; Maeda, K-I; Tsukamura, H

2013-03-01

Female rats show a gonadotrophin-releasing hormone (GnRH)/luteinising hormone (LH) surge in the presence of a preovulatory level of oestrogen, whereas males do not because of brain defeminisation during the developmental period by perinatal oestrogen converted from androgen. The present study aimed to identify the site(s) of oestrogen action and the critical period for defeminising the mechanism regulating the GnRH/LH surge. Animals given perinatal treatments, such as steroidal manipulations, brain local implantation of oestradiol (E(2) ) or administration of an NMDA antagonist, were examined for their ability to show an E(2) -induced LH surge at adulthood. Lordosis behaviour was examined to compare the mechanisms defeminising the GnRH/LH surge and sexual behaviour. A single s.c. oestradiol-benzoate administration on either the day before birth (E21), the day of birth (D0) or day 5 (D5) postpartum completely abolished the E(2) -induced LH surge at adulthood in female rats, although the same treatment did not inhibit lordosis. Perinatal castration on E21 or D0 partially rescued the E2-induced LH surge in genetically male rats, whereas castration from E21 to D5 totally rescued lordosis. Neonatal E(2) implantation in the anterior hypothalamus including the anteroventral periventricular nucleus (AVPV)/preoptic area (POA) abolished the E(2) -induced LH surge in female rats, whereas E(2) implantation in the mid and posterior hypothalamic regions had no inhibitory effect on the LH surge. Lordosis was not affected by neonatal E(2) implantation in any hypothalamic regions. In male rats, neonatal NMDA antagonist treatment rescued lordosis but not the LH surge. Taken together, these results suggest that an anterior hypothalamic region such as the AVPV/POA region is a perinatal site of oestrogen action where the GnRH/LH regulating system is defeminised to abolish the oestrogen-induced surge. The mechanism for defeminisation of the GnRH/LH surge system might be different from that of sexual behaviour, in terms of the site(s) of oestrogen action and critical period, as well as the neurotransmitter system involved. © 2012 British Society for Neuroendocrinology.

Toward an integrated storm surge application: ESA Storm Surge project

NASA Astrophysics Data System (ADS)

Lee, Boram; Donlon, Craig; Arino, Olivier

2010-05-01

Storm surges and their associated coastal inundation are major coastal marine hazards, both in tropical and extra-tropical areas. As sea level rises due to climate change, the impact of storm surges and associated extreme flooding may increase in low-lying countries and harbour cities. Of the 33 world cities predicted to have at least 8 million people by 2015, at least 21 of them are coastal including 8 of the 10 largest. They are highly vulnerable to coastal hazards including storm surges. Coastal inundation forecasting and warning systems depend on the crosscutting cooperation of different scientific disciplines and user communities. An integrated approach to storm surge, wave, sea-level and flood forecasting offers an optimal strategy for building improved operational forecasts and warnings capability for coastal inundation. The Earth Observation (EO) information from satellites has demonstrated high potential to enhanced coastal hazard monitoring, analysis, and forecasting; the GOCE geoid data can help calculating accurate positions of tide gauge stations within the GLOSS network. ASAR images has demonstrated usefulness in analysing hydrological situation in coastal zones with timely manner, when hazardous events occur. Wind speed and direction, which is the key parameters for storm surge forecasting and hindcasting, can be derived by using scatterometer data. The current issue is, although great deal of useful EO information and application tools exist, that sufficient user information on EO data availability is missing and that easy access supported by user applications and documentation is highly required. Clear documentation on the user requirements in support of improved storm surge forecasting and risk assessment is also needed at the present. The paper primarily addresses the requirements for data, models/technologies, and operational skills, based on the results from the recent Scientific and Technical Symposium on Storm Surges (www.surgesymposium.org, organized by the WMO-IOC Joint technical Commission for Oceanography and Marine Meteorology, JCOMM) and following activities, that have been supported by the Intergovernmental Oceanographic Commission (IOC) of UNESCO through JCOMM. The paper also reviews the capabilities of storm surge models, and current status in using Earth Observation (EO) information for advancing storm surge application tools, and further, for improving operational forecasts and warning capability for coastal inundation. In this context, the plans and expected results of the ESA Storm Surge Project (2010-2011) will be introduced.

Coordinated Ground and Space Measurements of Auroral Surge over South Pole.

DTIC Science & Technology

1988-02-01

3y V. Coordinated Ground and Space Measurements of co an Auroral Surge over South Pole T. J. ROSENBERG and D. L. DETRICK Institute for Physical...Measurements of an Auroral Surge over South Pole 12. PERSONAL AUTHOR(S) Rosenberg, T. J., and DetrickD. L., University of Maryland; Mizera, Paul F., 13a. TYPE...premidnight auroral surge over Amundsen-Scott South Pole station. The set of near-simultaneous measurements provides an excellent opportunity to gain a

Ketoconazole attenuates radiation-induction of tumor necrosis factor

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hallahan, D.E.; Virudachalam, S.; Kufe, D.W.

1994-07-01

Previous work has demonstrated that inhibitors of phospholipase A2 attenuate ionizing radiation-induced arachidonic acid production, protein kinase C activation, and prevent subsequent induction of the tumor necrosis factor gene. Because arachidonic acid contributes to radiation-induced tumor necrosis factor expression, the authors analyzed the effects of agents which alter arachidonate metabolism on the regulation of this gene. Phospholipase A2 inhibitors quinicrine, bromphenyl bromide, and pentoxyfylline or the inhibitor of lipoxygenase (ketoconazole) or the inhibitor of cycloxygenase (indomethacine) were added to cell culture 1 h prior to irradiation. Radiation-induced tumor necrosis factor gene expression was attenuated by each of the phospholipase A2more » inhibitors (quinicrine, bromphenylbromide, and pentoxyfylline). Furthermore, ketoconazole attenuated X ray induced tumor necrosis factor gene expression. Conversely, indomethacin enhanced tumor necrosis factor expression following irradiation. The finding that radiation-induced tumor necrosis factor gene expression was attenuated by ketoconazole suggests that the lipoxygenase pathway participates in signal transduction preceding tumor necrosis factor induction. Enhancement of tumor necrosis factor expression by indomethacin following irradiation suggests that prostaglandins produced by cyclooxygenase act as negative regulators of tumor necrosis factor expression. Inhibitors of tumor necrosis factor induction ameliorate acute and subacute sequelae of radiotherapy. The authors propose therefore, that ketoconazole may reduce acute radiation sequelae such as mucositis and esophagitis through a reduction in tumor necrosis factor induction or inhibition of phospholipase A2 in addition to its antifungal activity. 25 refs., 2 figs.« less

Preliminary Study on Coupling Wave-Tide-Storm Surges Prediction System

NASA Astrophysics Data System (ADS)

You, S.; Park, S.; Seo, J.; Kim, K.

2008-12-01

The Korean Peninsula is surrounded by the Yellow Sea, East China Sea, and East Sea. This complex oceanographic system includes large tides in the Yellow Sea and seasonally varying monsoon and typhoon events. For Korea's coastal regions, floods caused by wave and storm surges are among the most serious threats. To predict more accurate wave and storm surge, the development of coupling wave-tide-storm surges prediction system is essential. For the time being, wave and storm surges predictions are still made separately in KMA (Korea Meteorological Administration) and most operational institute. However, many researchers have emphasized the effects of tides and storm surges on wind waves and recommended further investigations into the effects of wave-tide-storm surges interactions and coupling module on wave heights. However, tidal height and current give a great effect on the wave prediction in the Yellow sea where is very high tide and related research is not enough. At present, KMA has operated the wave (RWAM : Regional Wave Model) and storm surges/tide prediction system (RTSM : Regional Tide/Storm Surges Model) for ocean forecasting. The RWAM is WAVEWATCH III which is a third generation wave model developed by Tolman (1989). The RTSM is based on POM (Princeton Ocean Model, Blumberg and Mellor, 1987). The RWAM and RTSM cover the northwestern Pacific Ocean from 115°E to 150°E and from 20°N to 52°N. The horizontal grid intervals are 1/12° in both latitudinal and longitudinal directions. The development, testing and application of a coupling module in which wave-tide-storm surges are incorporated within the frame of KMA Ocean prediction system, has been considered as a step forward in respect of ocean forecasting. In addition, advanced wave prediction model will be applicable to the effect of ocean in the weather forecasting system. The main purpose of this study is to show how the coupling module developed and to report on a series of experiments dealing with the sensitivities and real case prediction of coupling wave-tide-storm surges prediction system.

Investigating Typhoon Induced River-Surge Interactions in the Tamsui Estuary, Taiwan.

NASA Astrophysics Data System (ADS)

Maskell; J. H.; Grieser, J.; Rodney, J.; Howe, N. J.

2016-02-01

It is increasingly important to understand the combined influence of the main drivers of coastal risk due to sea level rise and the potential increase in extreme weather events. An Asian Basin stochastic typhoon set was used to force a storm surge model of Taiwan to investigate the interaction between storm surge and high river discharges (50, 100 and 200 year return period discharges) in the Tamsui River. Taiwan is a mountainous country leading to the combined risk of surge and high river discharge occurring simultaneously in estuary regions. The typhoon tracks were selected using a Hurricane Surge Index (Kantha, 2006) and cross the northern tip of Taiwan with maximum sustained winds (Vmax) between 51 m/s and 75 m/s (Cat 3-5). Peak surge elevations in the Tamsui River range from 5.7 m to 10.3 m. The surge interacts with the river flow to induce changes in the water elevation between -8 m and 4 m depending on the surge elevation and river discharge and increases the inundated area in the range 37 km to 204 km. Significant positive interactions occur in the Tamsui Estuary (Fig. 1a) but do not have implications for increased inundation and occur at the start of the flood phase and the end of the ebb phase as previously shown in idealized test cases (Maskell et al., 2013). Current vectors in the estuary show that at the time leading up to high water the river outflow starts to become dominant in the mid-channel reducing maximum water levels by up to 10% in the combined surge and river solution. However, surge inhibits downstream propagation of the flood wave in the upper river channels increasing water levels by up to 2 m. The maximum inundated area (1330 km2) is caused by the combination of defence overflow due to the maximum surge (10.27 m) and increased river levels (RP100) in the upper channels leading to significant inundation either side of the Keelung River (Fig. 1b). The Erchung floodway is effective in diverting some of the flow (up to 10,443 m3/s) reducing inundation elsewhere in the river network.

The use of coastal altimetry to support storm surge studies in project eSurge

NASA Astrophysics Data System (ADS)

Cipollini, P.; Harwood, P.; Snaith, H.; Vignudelli, S.; West, L.; Zecchetto, S.; Donlon, C.

2012-04-01

One of the most promising applications of the new field of coastal altimetry, i.e. the discipline aiming to recover meaningful estimates of geophysical parameters (sea level, significant wave height and wind speed) from satellite altimeter data in the coastal zone, is the study of storm surges. The understanding and realistic modelling of surges supports both preparation and mitigation activities and should eventually bring enormous societal benefits, especially to some of the world's poorest countries (like Bangladesh). Earth Observation data have an important role to play in storm surge monitoring and forecasting, but the full uptake of these data by users (such as environmental agencies and tidal prediction centres) must first be encouraged by showcasing their usefulness, and then supported by providing easy access. Having recognized the above needs, The European Space Agency has recently launched a Data User Element (DUE) project called eSurge. The main purposes of eSurge are a) to contribute to an integrated approach to storm surge, wave, sea-level and flood forecasting through Earth Observation, as part of a wider optimal strategy for building an improved forecast and early warning capability for coastal inundation; and b) to increase the use of the advanced capabilities of ESA and other satellite data for storm surge applications. The project is led by Logica UK, with NOC (UK), DMI (Denmark), CMRC (Ireland) and KNMI (Netherlands) as scientific partners. A very important component of eSurge is the development, validation and provision of dedicated coastal altimetry products, which is the focus of the present contribution. Coastal altimetry has a prominent role to play as it measures the total water level envelope directly, and this is one of the key quantities required by storm surge applications and services. But it can also provide important information on the wave field in the coastal strip, which helps the development of more realistic wave models that in turn can be used to improve the forecast of wave setup and overtopping processes. We will present examples of how altimetry has captured a few significant surge events in European Seas, and we will describe how a multi-mission coastal altimetry processor is going to be integrated in the eSurge system. The delayed-time reprocessed coastal altimetry data will be blended with tide gauge data to extract the main modes of variability in the coastal regions. Then data from the tide gauges can be used to estimate water level in real time, based on the modes of variability found. In a later phase of the project, the eSurge coastal altimetry processor will be extended to be able to ingest Near-Real-time (NRT) raw altimetric waveforms and generate the relevant NRT products, a definite first for coastal altimetry. The pilot regions for this application will be the European Seas (where an area of specific interest is the Northern Adriatic, which is being investigated within a related initiative called eSurge-Venice) and the North Indian Ocean. In summary, we expect eSurge to be one of the first pre-operational applications of coastal altimetry and a proof of the benefits to society that can be brought by this relatively new branch of marine remote sensing.

Ground potential rise monitor

DOEpatents

Allen, Zachery W [Mandan, ND; Zevenbergen, Gary A [Arvada, CO

2012-04-03

A device and method for detecting ground potential rise (GPR) comprising positioning a first electrode and a second electrode at a distance from each other into the earth. The voltage of the first electrode and second electrode is attenuated by an attenuation factor creating an attenuated voltage. The true RMS voltage of the attenuated voltage is determined creating an attenuated true RMS voltage. The attenuated true RMS voltage is then multiplied by the attenuation factor creating a calculated true RMS voltage. If the calculated true RMS voltage is greater than a first predetermined voltage threshold, a first alarm is enabled at a local location. If user input is received at a remote location acknowledging the first alarm, a first alarm acknowledgment signal is transmitted. The first alarm acknowledgment signal is then received at which time the first alarm is disabled.

Developing an early warning system for storm surge inundation in the Philippines

NASA Astrophysics Data System (ADS)

Tablazon, Judd; Mahar Francisco Lagmay, Alfredo; Francia Mungcal, Ma. Theresa; Gonzalo, Lia Anne; Dasallas, Lea; Briones, Jo Brianne Louise; Santiago, Joy; Suarez, John Kenneth; Lapidez, John Phillip; Caro, Carl Vincent; Ladiero, Christine; Malano, Vicente

2014-05-01

A storm surge is the sudden rise of sea water generated by an approaching storm, over and above the astronomical tides. This event imposes a major threat in the Philippine coastal areas, as manifested by Typhoon Haiyan on 08 November 2013 where more than 6,000 people lost their lives. It has become evident that the need to develop an early warning system for storm surges is of utmost importance. To provide forecasts of the possible storm surge heights of an approaching typhoon, the Nationwide Operational Assessment of Hazards under the Department of Science and Technology (DOST-Project NOAH) simulated historical tropical cyclones that entered the Philippine Area of Responsibility. Bathymetric data, storm track, central atmospheric pressure, and maximum wind speed were used as parameters for the Japan Meteorological Agency (JMA) Storm Surge Model. The researchers calculated the frequency distribution of maximum storm surge heights of all typhoons under a specific Public Storm Warning Signal (PSWS) that passed through a particular coastal area. This determines the storm surge height corresponding to a given probability of occurrence. The storm surge heights from the model were added to the maximum astronomical tide data from WXTide software. The team then created maps of probable area inundation and flood levels of storm surges along coastal areas for a specific PSWS using the results of the frequency distribution. These maps were developed from the time series data of the storm tide at 10-minute intervals of all observation points in the Philippines. This information will be beneficial in developing early warnings systems, static maps, disaster mitigation and preparedness plans, vulnerability assessments, risk-sensitive land use plans, shoreline defense efforts, and coastal protection measures. Moreover, these will support the local government units' mandate to raise public awareness, disseminate information about storm surge hazards, and implement appropriate counter-measures for a given PSWS.

Developing an early warning system for storm surge inundation in the Philippines

NASA Astrophysics Data System (ADS)

Tablazon, J.; Caro, C. V.; Lagmay, A. M. F.; Briones, J. B. L.; Dasallas, L.; Lapidez, J. P.; Santiago, J.; Suarez, J. K.; Ladiero, C.; Gonzalo, L. A.; Mungcal, M. T. F.; Malano, V.

2014-10-01

A storm surge is the sudden rise of sea water generated by an approaching storm, over and above the astronomical tides. This event imposes a major threat in the Philippine coastal areas, as manifested by Typhoon Haiyan on 8 November 2013 where more than 6000 people lost their lives. It has become evident that the need to develop an early warning system for storm surges is of utmost importance. To provide forecasts of the possible storm surge heights of an approaching typhoon, the Nationwide Operational Assessment of Hazards under the Department of Science and Technology (DOST-Project NOAH) simulated historical tropical cyclones that entered the Philippine Area of Responsibility. Bathymetric data, storm track, central atmospheric pressure, and maximum wind speed were used as parameters for the Japan Meteorological Agency Storm Surge Model. The researchers calculated the frequency distribution of maximum storm surge heights of all typhoons under a specific Public Storm Warning Signal (PSWS) that passed through a particular coastal area. This determines the storm surge height corresponding to a given probability of occurrence. The storm surge heights from the model were added to the maximum astronomical tide data from WXTide software. The team then created maps of probable area inundation and flood levels of storm surges along coastal areas for a specific PSWS using the results of the frequency distribution. These maps were developed from the time series data of the storm tide at 10 min intervals of all observation points in the Philippines. This information will be beneficial in developing early warnings systems, static maps, disaster mitigation and preparedness plans, vulnerability assessments, risk-sensitive land use plans, shoreline defense efforts, and coastal protection measures. Moreover, these will support the local government units' mandate to raise public awareness, disseminate information about storm surge hazards, and implement appropriate counter-measures for a given PSWS.

A Two-Step Method to Select Major Surge-Producing Extratropical Cyclones from a 10,000-Year Stochastic Catalog

NASA Astrophysics Data System (ADS)

Keshtpoor, M.; Carnacina, I.; Yablonsky, R. M.

2016-12-01

Extratropical cyclones (ETCs) are the primary driver of storm surge events along the UK and northwest mainland Europe coastlines. In an effort to evaluate the storm surge risk in coastal communities in this region, a stochastic catalog is developed by perturbing the historical storm seeds of European ETCs to account for 10,000 years of possible ETCs. Numerical simulation of the storm surge generated by the full 10,000-year stochastic catalog, however, is computationally expensive and may take several months to complete with available computational resources. A new statistical regression model is developed to select the major surge-generating events from the stochastic ETC catalog. This regression model is based on the maximum storm surge, obtained via numerical simulations using a calibrated version of the Delft3D-FM hydrodynamic model with a relatively coarse mesh, of 1750 historical ETC events that occurred over the past 38 years in Europe. These numerically-simulated surge values were regressed to the local sea level pressure and the U and V components of the wind field at the location of 196 tide gauge stations near the UK and northwest mainland Europe coastal areas. The regression model suggests that storm surge values in the area of interest are highly correlated to the U- and V-component of wind speed, as well as the sea level pressure. Based on these correlations, the regression model was then used to select surge-generating storms from the 10,000-year stochastic catalog. Results suggest that roughly 105,000 events out of 480,000 stochastic storms are surge-generating events and need to be considered for numerical simulation using a hydrodynamic model. The selected stochastic storms were then simulated in Delft3D-FM, and the final refinement of the storm population was performed based on return period analysis of the 1750 historical event simulations at each of the 196 tide gauges in preparation for Delft3D-FM fine mesh simulations.

Storm surge and tidal range energy

NASA Astrophysics Data System (ADS)

Lewis, Matthew; Angeloudis, Athanasios; Robins, Peter; Evans, Paul; Neill, Simon

2017-04-01

The need to reduce carbon-based energy sources whilst increasing renewable energy forms has led to concerns of intermittency within a national electricity supply strategy. The regular rise and fall of the tide makes prediction almost entirely deterministic compared to other stochastic renewable energy forms; therefore, tidal range energy is often stated as a predictable and firm renewable energy source. Storm surge is the term used for the non-astronomical forcing of tidal elevation, and is synonymous with coastal flooding because positive storm surges can elevate water-levels above the height of coastal flood defences. We hypothesis storm surges will affect the reliability of the tidal range energy resource; with negative surge events reducing the tidal range, and conversely, positive surge events increasing the available resource. Moreover, tide-surge interaction, which results in positive storm surges more likely to occur on a flooding tide, will reduce the annual tidal range energy resource estimate. Water-level data (2000-2012) at nine UK tide gauges, where the mean tidal amplitude is above 2.5m and thus suitable for tidal-range energy development (e.g. Bristol Channel), were used to predict tidal range power with a 0D modelling approach. Storm surge affected the annual resource estimate by between -5% to +3%, due to inter-annual variability. Instantaneous power output were significantly affected (Normalised Root Mean Squared Error: 3%-8%, Scatter Index: 15%-41%) with spatial variability and variability due to operational strategy. We therefore find a storm surge affects the theoretical reliability of tidal range power, such that a prediction system may be required for any future electricity generation scenario that includes large amounts of tidal-range energy; however, annual resource estimation from astronomical tides alone appears sufficient for resource estimation. Future work should investigate water-level uncertainties on the reliability and predictability of tidal range energy with 2D hydrodynamic models.

Model-data comparisons of crevasses in accelerating glaciers exemplified for the 2011-2013 surge of Bering Glacier, Alaska

NASA Astrophysics Data System (ADS)

Trantow, T.; Herzfeld, U. C.

2017-12-01

Glacier acceleration, ubiquitous along the periphery of the major icesheets, presents one of the main uncertainties in modeling future global sea-level rise according to the IPCC 5th Assessment Report (2013). The surge phenomenon is one type of glacial acceleration and is the least understood. During a surge, large-scale elevation change and significant crevassing occurs throughout the entire ice system. Crevasses are the most obvious manifestations of the surge dynamics and provide a source of geophysical information that allows reconstruction of deformation processes. The recent surge of the Bering-Bagley Glacier System (BBGS), Alaska, in 2011-2013 provides an excellent test case to study surging through airborne and satellite observations together with numerical modeling. A 3D full-Stokes finite element model of the BBGS has been created using the Elmer/Ice software for structural and dynamical investigations of the surge. A von Mises condition is applied to modeled surface stresses to predict where crevassing would occur during the surge. The model uses CryoSat-2 derived surface topography (Baseline-C), bedrock topography, Glen's flow law with an isothermal assumption and a uniform linear friction law at the ice/bedrock boundary to represent the surge state in early 2011 when peak velocities were observed. Additionally, geostatistical characterization applied to optical satellite imagery provides an observational data set for model-data comparisons. Observed and modeled crevasse characteristics are compared with respect to their location, magnitude and orientation. Similarity mapping applied to the modeled von Mises stress and observed surface roughness values indicates that the two quantities are correlated. Results indicate that large-scale surface crevasses resulting from a surge are connected to the bedrock topography of the glacier system. The model-data comparisons used in this analysis serve to validate the numerical model and provide insight into the quality of our model input.

The basal fallout and surge deposits of the mafic ignimbrite-forming Villa Senni Eruption Unit, (Colli Albani volcano, Italy)

NASA Astrophysics Data System (ADS)

Vinkler, A.; Ort, M. H.; Giordano, G.

2009-12-01

The Villa Senni Eruption Unit (350ka) represents the youngest large caldera-forming eruption of the Colli Albani volcano near Rome (Italy). The Colli Albani magma is marked by very undersaturated chemistry (tephritic to K-foiditic) and low viscosity. The total volume of the Villa Senni Eruption Unit is estimated at > 50 km3 and 30 km3 DRE (Watkins et al., 2002). The unit includes a sequence of a basal fallout/surge deposit, two main ignimbrites emplaced during the same eruptive event, a series of breccia deposits positioned between the two ignimbrites, and a rarely preserved final fallout. The basal surge and fallout sequence may help answer questions regarding the beginning of a large mafic ignimbrite eruption. The entire surge and fallout deposit is 190 cm thick at the caldera wall, consisting of 19 individual, parallel to faintly cross-stratified layers. The deposit distally thins to 25 cm at 18 km east of the caldera and to 2.5 cm at 21 km NW of the caldera. The eruption started with fine ash surges showing cross-stratification at proximal locations and being vesicular distally. The deposit consists mainly of juvenile clasts, which are angular, poorly vesicular, and rich in leucite microlites (~80 µm). Clasts around 100-150 μm show signs of magma-water interaction: quench fracturing: conchoidal and step fractures, smooth surfaces, adhering clasts and melt film. These features are present in several thin alternating surge and fall sequences at the base of the deposit. The lithic clasts in these first deposits are concentrated in layers, indicating pulsatory behavior of the eruption. Upward, the deposit consists of thicker, coarse ash to lapilli fallout layers from more sustained columns. The juvenile clasts in these deposits are more irregular, with higher vesicularity (but less than 50%) and smaller leucite microlites (~60 μm). The uppermost part of the basal fallout/surge deposit shows features transitional to the first large ignimbrite: fallout deposits alternate with poorly sorted flow units, with an increase in free leucite crystals and lithic content, with more abundant deep lithic clasts and a further leucite microlite size decrease (~20 μm) , which could indicate an accelerating magma in the conduit. We think that external factors, such as magma-water interaction and consequent gas explosions, triggered the highly explosive Villa Senni Eruption. Low vesicularity of the early juvenile clasts suggests the magma was relatively low in volatiles at the outset and did not start as a gas-driven eruption. Later in the eruption, the high ascent rate and fast decompression of the magma sustained a large explosive eruption.

Comparing Factors of Bachelor's Degree Attainment for First and Continuing Generation Students

ERIC Educational Resources Information Center

Hoffman, Holly Gilbertson

2014-01-01

Colleges and universities have recently been under great pressure to increase institutional graduation rates, due to a surge in consumer demand for accountability and the use of graduation rates to deter nine effectiveness and funding. Many colleges may choose to achieve higher graduation rates by simply increasing selectivity. However, this…

The Fate of the Civilian Surge in a Changing Environment

DTIC Science & Technology

2016-08-01

THE FATE OF THE CIVILIAN SURGE IN A CHANGING ENVIRONMENT Ryan S. McCannellUSAWC Website FOR THIS AND OTHER PUBLICATIONS, VISIT US AT http...FATE OF THE CIVILIAN SURGE IN A CHANGING ENVIRONMENT Ryan S. McCannell The views expressed in this report are those of the authors and do not...in Strategic Studies from the U.S. Army War College. 1 The Fate of the Civilian Surge in a Changing Environment Ryan S. McCannell Introduction

Developmental Programming: Prenatal and Postnatal Androgen Antagonist and Insulin Sensitizer Interventions Prevent Advancement of Puberty and Improve LH Surge Dynamics in Prenatal Testosterone-Treated Sheep

PubMed Central

Veiga-Lopez, Almudena; Herkimer, Carol; Abi Salloum, Bachir; Moeller, Jacob; Beckett, Evan; Sreedharan, Rohit

2015-01-01

Prenatal T excess induces maternal hyperinsulinemia, early puberty, and reproductive/metabolic defects in the female similar to those seen in women with polycystic ovary syndrome. This study addressed the organizational/activational role of androgens and insulin in programming pubertal advancement and periovulatory LH surge defects. Treatment groups included the following: 1) control; 2) prenatal T; 3) prenatal T plus prenatal androgen antagonist, flutamide; 4) prenatal T plus prenatal insulin sensitizer, rosiglitazone; 5) prenatal T and postnatal flutamide; 6) prenatal T and postnatal rosiglitazone; and 7) prenatal T and postnatal metformin. Prenatal treatments spanned 30–90 days of gestation and postnatal treatments began at approximately 8 weeks of age and continued throughout. Blood samples were taken twice weekly, beginning at approximately 12 weeks of age to time puberty. Two-hour samples after the synchronization with prostaglandin F2α were taken for 120 hours to characterize LH surge dynamics at 7 and 19 months of age. Prenatal T females entered puberty earlier than controls, and all interventions prevented this advancement. Prenatal T reduced the percentage of animals having LH surge, and females that presented LH surge exhibited delayed timing and dampened amplitude of the LH surge. Prenatal androgen antagonist, but not other interventions, restored LH surges without normalizing the timing of the surge. Normalization of pubertal timing with prenatal/postnatal androgen antagonist and insulin sensitizer interventions suggests that pubertal advancement is programmed by androgenic actions of T involving insulin as a mediary. Restoration of LH surges by cotreatment with androgen antagonist supports androgenic programming at the organizational level. PMID:25919188

Developmental Programming: Prenatal and Postnatal Androgen Antagonist and Insulin Sensitizer Interventions Prevent Advancement of Puberty and Improve LH Surge Dynamics in Prenatal Testosterone-Treated Sheep.

PubMed

Padmanabhan, Vasantha; Veiga-Lopez, Almudena; Herkimer, Carol; Abi Salloum, Bachir; Moeller, Jacob; Beckett, Evan; Sreedharan, Rohit

2015-07-01

Prenatal T excess induces maternal hyperinsulinemia, early puberty, and reproductive/metabolic defects in the female similar to those seen in women with polycystic ovary syndrome. This study addressed the organizational/activational role of androgens and insulin in programming pubertal advancement and periovulatory LH surge defects. Treatment groups included the following: 1) control; 2) prenatal T; 3) prenatal T plus prenatal androgen antagonist, flutamide; 4) prenatal T plus prenatal insulin sensitizer, rosiglitazone; 5) prenatal T and postnatal flutamide; 6) prenatal T and postnatal rosiglitazone; and 7) prenatal T and postnatal metformin. Prenatal treatments spanned 30-90 days of gestation and postnatal treatments began at approximately 8 weeks of age and continued throughout. Blood samples were taken twice weekly, beginning at approximately 12 weeks of age to time puberty. Two-hour samples after the synchronization with prostaglandin F2α were taken for 120 hours to characterize LH surge dynamics at 7 and 19 months of age. Prenatal T females entered puberty earlier than controls, and all interventions prevented this advancement. Prenatal T reduced the percentage of animals having LH surge, and females that presented LH surge exhibited delayed timing and dampened amplitude of the LH surge. Prenatal androgen antagonist, but not other interventions, restored LH surges without normalizing the timing of the surge. Normalization of pubertal timing with prenatal/postnatal androgen antagonist and insulin sensitizer interventions suggests that pubertal advancement is programmed by androgenic actions of T involving insulin as a mediary. Restoration of LH surges by cotreatment with androgen antagonist supports androgenic programming at the organizational level.

Neurokinin-3 Receptor Activation in the Retrochiasmatic Area is Essential for the Full Preovulatory LH Surge in Ewes

PubMed Central

Porter, Katrina L.; Hileman, Stanley M.; Hardy, Steven L.; Nestor, Casey C; Lehman, Michael N.; Goodman, Robert L.

2014-01-01

Neurokinin B (NKB) is essential for human reproduction and has been shown to stimulate LH secretion in several species, including sheep. Ewes express the neurokinin-3 receptor (NK3R) in the retrochiasmatic area (RCh) and there is one report that placement of senktide, an NK3R agonist, therein stimulates LH secretion that resembles an LH surge in ewes. In this study, we first confirmed that local administration of senktide to the RCh produced a surge-like increase in LH secretion, and then tested the effects of this agonist in two other areas implicated in the control of LH secretion and where NK3R is found in high abundance: the preoptic area (POA) and arcuate nucleus (ARC). Bilateral microimplants containing senktide induced a dramatic surge-like increase in LH when given in the POA similar to that seen with RCh treatment. In contrast, senktide treatment in the ARC resulted in a much smaller, but significant, increase in LH concentrations suggestive of an effect on tonic secretion. The possible role of POA and RCh NK3R activation in the LH surge was next tested by treating ewes with SB222200, an NK3R antagonist, in each area during an E2-induced LH surge. SB222200 in the RCh, but not in the POA, reduced LH surge amplitude by about 40% compared to controls, indicating that NK3R activation in the former region is essential for full expression of the preovulatory LH surge. Based on these data, we propose that NKB actions in the RCh are an important component of the preovulatory LH surge in ewes. PMID:25040132

Storm Surge Modeling of Typhoon Haiyan at the Naval Oceanographic Office Using Delft3D

NASA Astrophysics Data System (ADS)

Gilligan, M. J.; Lovering, J. L.

2016-02-01

The Naval Oceanographic Office provides estimates of the rise in sea level along the coast due to storm surge associated with tropical cyclones, typhoons, and hurricanes. Storm surge modeling and prediction helps the US Navy by providing a threat assessment tool to help protect Navy assets and provide support for humanitarian assistance/disaster relief efforts. Recent advancements in our modeling capabilities include the use of the Delft3D modeling suite as part of a Naval Research Laboratory (NRL) developed Coastal Surge Inundation Prediction System (CSIPS). Model simulations were performed on Typhoon Haiyan, which made landfall in the Philippines in November 2013. Comparisons of model simulations using forecast and hindcast track data highlight the importance of accurate storm track information for storm surge predictions. Model runs using the forecast track prediction and hindcast track information give maximum storm surge elevations of 4 meters and 6.1 meters, respectively. Model results for the hindcast simulation were compared with data published by the JSCE-PICE Joint survey for locations in San Pedro Bay (SPB) and on the Eastern Samar Peninsula (ESP). In SPB, where wind-induced set-up predominates, the model run using the forecast track predicted surge within 2 meters in 38% of survey locations and within 3 meters in 59% of the locations. When the hindcast track was used, the model predicted within 2 meters in 77% of the locations and within 3 meters in 95% of the locations. The model was unable to predict the high surge reported along the ESP produced by infragravity wave-induced set-up, which is not simulated in the model. Additional modeling capabilities incorporating infragravity waves are required to predict storm surge accurately along open coasts with steep bathymetric slopes, such as those seen in island arcs.

Cerebral blood flow modulation by Basal forebrain or whisker stimulation can occur independently of large cytosolic Ca2+ signaling in astrocytes.

PubMed

Takata, Norio; Nagai, Terumi; Ozawa, Katsuya; Oe, Yuki; Mikoshiba, Katsuhiko; Hirase, Hajime

2013-01-01

We report that a brief electrical stimulation of the nucleus basalis of Meynert (NBM), the primary source of cholinergic projection to the cerebral cortex, induces a biphasic cerebral cortical blood flow (CBF) response in the somatosensory cortex of C57BL/6J mice. This CBF response, measured by laser Doppler flowmetry, was attenuated by the muscarinic type acetylcholine receptor antagonist atropine, suggesting a possible involvement of astrocytes in this type of CBF modulation. However, we find that IP3R2 knockout mice, which lack cytosolic Ca2+ surges in astrocytes, show similar CBF changes. Moreover, whisker stimulation resulted in similar degrees of CBF increase in IP3R2 knockout mice and the background strain C57BL/6J. Our results show that neural activity-driven CBF modulation could occur without large cytosolic increases of Ca2+ in astrocytes.

Swept-Source Optical Coherence Tomography Angiography in West Nile Virus Chorioretinitis and Associated Occlusive Retinal Vasculitis.

PubMed

Khairallah, Moncef; Kahloun, Rim; Gargouri, Salma; Jelliti, Bechir; Sellami, Dorra; Ben Yahia, Salim; Feki, Jamel

2017-08-01

A 65-year-old man with diabetes and a history of fever of unknown origin 2 weeks earlier complained of sudden decreased vision in the left eye. The patient was diagnosed with bilateral West Nile virus (WNV) chorioretinitis associated with occlusive retinal vasculitis in the left eye. Swept-source optical coherence tomography angiography (SS-OCTA) of the left eye showed extensive, well-delineated, hypointense non-perfusion areas and perifoveal capillary arcade disruption in the superficial capillary plexus, as well as larger non-perfusion areas, capillary rarefaction, and diffuse capillary network attenuation and disorganization in the deep capillary plexus. OCTA may be a valuable tool for noninvasively assessing occlusive retinal vasculitis associated with WNV infection. It allows an accurate detection and precise delineation of areas of retinal capillary nonperfusion in both the superficial and deep capillary plexuses. [Ophthalmic Surg Lasers Imaging Retina. 2017;48:672-675.]. Copyright 2017, SLACK Incorporated.

A core review of temperature regimens and neuroprotection during cardiopulmonary bypass: does rewarming rate matter?

PubMed

Grigore, Alina M; Murray, Catherine Friederich; Ramakrishna, Harish; Djaiani, George

2009-12-01

Despite a half century of research and the implementation of various risk-reduction strategies among clinicians and basic scientists, patients continue to experience strokes and cognitive dysfunction related to the use of cardiopulmonary bypass (CPB) for cardiac surgery. One strategy to reduce these detrimental effects has been the use of hypothermia. Although numerous studies have addressed the issue, the question of whether the use of hypothermia during CPB attenuates the impact of central nervous system consequences remains unresolved. However, data clearly demonstrate that hyperthermia is to be avoided in the perioperative period, necessitating careful rewarming strategies if hypothermia is used during CPB. Selecting and understanding the impact of the temperature-monitoring site is important to accurately estimate cerebral temperature and to avoid inadvertent surges in brain temperature. In this article, we review the literature regarding the impact of hypothermia and rewarming rates during cardiac surgery.

7 CFR 760.203 - Eligible losses, adverse weather, and other loss conditions.

Code of Federal Regulations, 2010 CFR

2010-01-01

... Administrator, including, but not limited to, blizzard, flood, hurricane, tidal surge, tornado, volcanic... Administrator, including, but not limited to, blizzard, flood, hurricane, tidal surge, tornado, volcanic... wind, flood, hurricane, tidal surge, tornado, volcanic eruption, and wildfire. (h) For honeybee colony...

7 CFR 760.203 - Eligible losses, adverse weather, and other loss conditions.

Code of Federal Regulations, 2011 CFR

2011-01-01

... Administrator, including, but not limited to, blizzard, flood, hurricane, tidal surge, tornado, volcanic... Administrator, including, but not limited to, blizzard, flood, hurricane, tidal surge, tornado, volcanic... wind, flood, hurricane, tidal surge, tornado, volcanic eruption, and wildfire. (h) For honeybee colony...

7 CFR 760.203 - Eligible losses, adverse weather, and other loss conditions.

Code of Federal Regulations, 2013 CFR

2013-01-01

... limited to, blizzard, flood, hurricane, tidal surge, tornado, volcanic eruption, wildfire on non-Federal... to, blizzard, flood, hurricane, tidal surge, tornado, volcanic eruption, wildfire on non-Federal land... limited to, earthquake, excessive wind, flood, hurricane, tidal surge, tornado, volcanic eruption, and...

7 CFR 760.203 - Eligible losses, adverse weather, and other loss conditions.

Code of Federal Regulations, 2012 CFR

2012-01-01

... limited to, blizzard, flood, hurricane, tidal surge, tornado, volcanic eruption, wildfire on non-Federal... to, blizzard, flood, hurricane, tidal surge, tornado, volcanic eruption, wildfire on non-Federal land... limited to, earthquake, excessive wind, flood, hurricane, tidal surge, tornado, volcanic eruption, and...

7 CFR 760.203 - Eligible losses, adverse weather, and other loss conditions.

Code of Federal Regulations, 2014 CFR

2014-01-01

... limited to, blizzard, flood, hurricane, tidal surge, tornado, volcanic eruption, wildfire on non-Federal... to, blizzard, flood, hurricane, tidal surge, tornado, volcanic eruption, wildfire on non-Federal land... limited to, earthquake, excessive wind, flood, hurricane, tidal surge, tornado, volcanic eruption, and...

Directional Analysis of the Storm Surge from Hurricane Sandy 2012, with Applications to Charleston, New Orleans, and the Philippines

PubMed Central

Drews, Carl; Galarneau, Thomas J.

2015-01-01

Hurricane Sandy in late October 2012 drove before it a storm surge that rose to 4.28 meters above mean lower low water at The Battery in lower Manhattan, and flooded the Hugh L. Carey automobile tunnel between Brooklyn and The Battery. This study examines the surge event in New York Harbor using the Weather Research and Forecasting (WRF) atmospheric model and the Coupled-Ocean-Atmosphere-Wave- Sediment Transport / Regional Ocean Modeling System (COAWST/ROMS). We present a new technique using directional analysis to calculate and display maps of a coastline's potential for storm surge; these maps are constructed from wind fields blowing from eight fixed compass directions. This analysis approximates the surge observed during Hurricane Sandy. The directional analysis is then applied to surge events at Charleston, South Carolina, New Orleans, Louisiana, and Tacloban City, the Philippines. Emergency managers could use these directional maps to prepare their cities for an approaching storm, on planning horizons from days to years. PMID:25822480

Local amplification of storm surge by Super Typhoon Haiyan in Leyte Gulf

PubMed Central

Mori, Nobuhito; Kato, Masaya; Kim, Sooyoul; Mase, Hajime; Shibutani, Yoko; Takemi, Tetsuya; Tsuboki, Kazuhisa; Yasuda, Tomohiro

2014-01-01

Typhoon Haiyan, which struck the Philippines in November 2013, was an extremely intense tropical cyclone that had a catastrophic impact. The minimum central pressure of Typhoon Haiyan was 895 hPa, making it the strongest typhoon to make landfall on a major island in the western North Pacific Ocean. The characteristics of Typhoon Haiyan and its related storm surge are estimated by numerical experiments using numerical weather prediction models and a storm surge model. Based on the analysis of best hindcast results, the storm surge level was 5–6 m and local amplification of water surface elevation due to seiche was found to be significant inside Leyte Gulf. The numerical experiments show the coherent structure of the storm surge profile due to the specific bathymetry of Leyte Gulf and the Philippines Trench as a major contributor to the disaster in Tacloban. The numerical results also indicated the sensitivity of storm surge forecast. PMID:25821268

The effect of wave current interactions on the storm surge and inundation in Charleston Harbor during Hurricane Hugo 1989

NASA Astrophysics Data System (ADS)

Xie, Lian; Liu, Huiqing; Peng, Machuan

The effects of wave-current interactions on the storm surge and inundation induced by Hurricane Hugo in and around the Charleston Harbor and its adjacent coastal regions are examined by using a three-dimensional (3-D) wave-current coupled modeling system. The 3-D storm surge and inundation modeling component of the coupled system is based on the Princeton ocean model (POM), whereas the wave modeling component is based on the third-generation wave model, simulating waves nearshore (SWAN). The results indicate that the effects of wave-induced surface, bottom, and radiation stresses can separately or in combination produce significant changes in storm surge and inundation. The effects of waves vary spatially. In some areas, the contribution of waves to peak storm surge during Hurricane Hugo reached as high as 0.76 m which led to substantial changes in the inundation and drying areas simulated by the storm surge model.

Directional analysis of the storm surge from Hurricane Sandy 2012, with applications to Charleston, New Orleans, and the Philippines.

PubMed

Drews, Carl; Galarneau, Thomas J

2015-01-01

Hurricane Sandy in late October 2012 drove before it a storm surge that rose to 4.28 meters above mean lower low water at The Battery in lower Manhattan, and flooded the Hugh L. Carey automobile tunnel between Brooklyn and The Battery. This study examines the surge event in New York Harbor using the Weather Research and Forecasting (WRF) atmospheric model and the Coupled-Ocean-Atmosphere-Wave- Sediment Transport/Regional Ocean Modeling System (COAWST/ROMS). We present a new technique using directional analysis to calculate and display maps of a coastline's potential for storm surge; these maps are constructed from wind fields blowing from eight fixed compass directions. This analysis approximates the surge observed during Hurricane Sandy. The directional analysis is then applied to surge events at Charleston, South Carolina, New Orleans, Louisiana, and Tacloban City, the Philippines. Emergency managers could use these directional maps to prepare their cities for an approaching storm, on planning horizons from days to years.

Question mark ears, temporo-mandibular joint malformation and hypotonia: auriculo-condylar syndrome or a distinct entity?

PubMed

Priolo, M; Lerone, M; Rosaia, L; Calcagno, E P; Sadeghi, A K; Ghezzi, F; Ravazzolo, R; Silengo, M

2000-10-01

We report a boy with prominent, peculiarly malformed ears, abnormality of the ramus of the mandible and hypotonia. An isolated peculiar bilateral ear deformity named 'question mark ear' has been delineated in plastic reconstruction surgery reviews [Cosman et al., 1970 Plast Reconstr Surg 46:454-457; Cosman (1984) Plast Reconstr Surg 73:572-576; Takato et al. (1989) Ann Plast Surg 22:69-73; Brodovsky (1997) Plast Reconstr Surg 100:1254-1257; Park (1998) Plast Reconstr Surg 101:1620-1623; Al-Quattan (1998) Plast Reconstr Surg 102:439-441] and a similar deformity of the ear and changes in the temporo-mandibular joint and condyle has been described by Jampol et al. [(1998) Am J Med Genet 75:449-452] and by Guion-Almeida et al. [(1999) Am J Med Genet 86:130-133]. The present case may be the third description of this malformation complex with additional clinical features characterized by hypotonia and mild developmental delay, or possibly a new distinct entity.

A New Approach for Quantitative Evaluation of Ultrasonic Wave Attenuation in Composites

NASA Astrophysics Data System (ADS)

Ni, Qing-Qing; Li, Ran; Xia, Hong

2017-02-01

When ultrasonic waves propagate in composite materials, the propagation behaviors result from the combination effects of various factors, such as material anisotropy and viscoelastic property, internal microstructure and defects, incident wave characteristics and interface condition between composite components. It is essential to make it clear how these factors affect the ultrasonic wave propagation and attenuation characteristics, and how they mutually interact on each other. In the present paper, based on a newly developed time-domain finite element analysis code, PZflex, a unique approach for clarifying the detailed influence mechanism of aforementioned factors is proposed, in which each attenuation component can be extracted from the overall attenuation and analyzed respectively. By taking into consideration the interrelation between each individual attenuation component, the variation behaviors of each component and internal dynamic stress distribution against material anisotropy and matrix viscosity are separately and quantitatively evaluated. From the detailed analysis results of each attenuation component, the energy dissipation at interface is a major component in ultrasonic wave attenuation characteristics, which can provide a maximum contribution rate of 68.2 % to the overall attenuation, and each attenuation component is closely related to the material anisotropy and viscoelasticity. The results clarify the correlation between ultrasonic wave propagation characteristics and material viscoelastic properties, which will be useful in the further development of ultrasonic technology in defect detection.

Developments in Surge Research Priorities: A Systematic Review of the Literature Following the Academic Emergency Medicine Consensus Conference, 2007-2015.

PubMed

Morton, Melinda J; DeAugustinis, Matthew L; Velasquez, Christina A; Singh, Sonal; Kelen, Gabor D

2015-11-01

In 2006, Academic Emergency Medicine (AEM) published a special issue summarizing the proceedings of the AEM consensus conference on the "Science of Surge." One major goal of the conference was to establish research priorities in the field of "disasters" surge. For this review, we wished to determine the progress toward the conference's identified research priorities: 1) defining criteria and methods for allocation of scarce resources, 2) identifying effective triage protocols, 3) determining decision-makers and means to evaluate response efficacy, 4) developing communication and information sharing strategies, and 5) identifying methods for evaluating workforce needs. Specific criteria were developed in conjunction with library search experts. PubMed, Embase, Web of Science, Scopus, and the Cochrane Library databases were queried for peer-reviewed articles from 2007 to 2015 addressing scientific advances related to the above five research priorities identified by AEM consensus conference. Abstracts and foreign language articles were excluded. Only articles with quantitative data on predefined outcomes were included; consensus panel recommendations on the above priorities were also included for the purposes of this review. Included study designs were randomized controlled trials, prospective, retrospective, qualitative (consensus panel), observational, cohort, case-control, or controlled before-and-after studies. Quality assessment was performed using a standardized tool for quantitative studies. Of the 2,484 unique articles identified by the search strategy, 313 articles appeared to be related to disaster surge. Following detailed text review, 50 articles with quantitative data and 11 concept papers (consensus conference recommendations) addressed at least one AEM consensus conference surge research priority. Outcomes included validation of the benchmark of 500 beds/million of population for disaster surge capacity, effectiveness of simulation- and Internet-based tools for forecasting of hospital and regional demand during disasters, effectiveness of reverse triage approaches, development of new disaster surge metrics, validation of mass critical care approaches (altered standards of care), use of telemedicine, and predictions of optimal hospital staffing levels for disaster surge events. Simulation tools appeared to provide some of the highest quality research. Disaster simulation studies have arguably revolutionized the study of disaster surge in the intervening years since the 2006 AEM Science of Surge conference, helping to validate some previously known disaster surge benchmarks and to generate new surge metrics. Use of reverse triage approaches and altered standards of care, as well as Internet-based tools such as Google Flu Trends, have also proven effective. However, there remains significant work to be done toward standardizing research methodologies and outcomes, as well as validating disaster surge metrics. © 2015 by the Society for Academic Emergency Medicine.

Interrelations among pyroclastic surge, pyroclastic flow, and lahars in Smith Creek valley during first minutes of 18 May 1980 eruption of Mount St. Helens, USA

USGS Publications Warehouse

Brantley, S.R.; Waitt, R.B.

1988-01-01

A devastating pyroclastic surge and resultant lahars at Mount St. Helens on 18 May 1980 produced several catastrophic flowages into tributaries on the northeast volcano flank. The tributaries channeled the flows to Smith Creek valley, which lies within the area devastated by the surge but was unaffected by the great debris avalanche on the north flank. Stratigraphy shows that the pyroclastic surge preceded the lahars; there is no notable "wet" character to the surge deposits. Therefore the lahars must have originated as snowmelt, not as ejected water-saturated debris that segregated from the pyroclastic surge as has been inferred for other flanks of the volcano. In stratigraphic order the Smith Creek valley-floor materials comprise (1) a complex valley-bottom facies of the pyroclastic surge and a related pyroclastic flow, (2) an unusual hummocky diamict caused by complex mixing of lahars with the dry pyroclastic debris, and (3) deposits of secondary pyroclastic flows. These units are capped by silt containing accretionary lapilli, which began falling from a rapidly expanding mushroom-shaped cloud 20 minutes after the eruption's onset. The Smith Creek valley-bottom pyroclastic facies consists of (a) a weakly graded basal bed of fines-poor granular sand, the deposit of a low-concentration lithic pyroclastic surge, and (b) a bed of very poorly sorted pebble to cobble gravel inversely graded near its base, the deposit of a high-concentration lithic pyroclastic flow. The surge apparently segregated while crossing the steep headwater tributaries of Smith Creek; large fragments that settled from the turbulent surge formed a dense pyroclastic flow along the valley floor that lagged behind the front of the overland surge. The unusual hummocky diamict as thick as 15 m contains large lithic clasts supported by a tough, brown muddy sand matrix like that of lahar deposits upvalley. This unit contains irregular friable lenses and pods meters in diameter, blocks incorporated from the underlying dry and hot pyroclastic material that had been deposited only moments earlier. The hummocky unit is the deposit of a high-viscosity debris flow which formed when lahars mingled with the pyroclastic materials on Smith Creek valley floor. Overlying the debris flow are voluminous pyroclastic deposits of pebbly sand cut by fines-poor gas-escape pipes and containing charred wood. The deposits are thickest in topographic lows along margins of the hummocky diamict. Emplaced several minutes after the hot surge had passed, this is the deposit of numerous secondary pyroclastic flows derived from surge material deposited unstably on steep valley sides. ?? 1988 Springer-Verlag.

Assessment of coastal flood risk in a changing climate along the northern Gulf of Mexico

NASA Astrophysics Data System (ADS)

Bilskie, M. V.; Hagen, S. C.; Passeri, D. L.; Alizad, K.

2014-12-01

Coastal regions around the world are susceptible to a variety of natural disasters causing extreme inundation. It is anticipated that the vulnerability of coastal cities will increase due to the effects of climate change, and in particular sea level rise (SLR). We have developed a novel framework to construct a physics-based storm surge model that includes projections of coastal floodplain dynamics under climate change scenarios. Numerous experiments were conducted and it was concluded that a number of influencing factors, other than SLR, should be included in future assessments of coastal flooding under climate change; e.g., shoreline changes, barrier island morphology, salt marsh migration, and population dynamics. These factors can significantly affect the path, pattern, and magnitude of flooding depths and inundation along the coastline (Bilskie et al., 2014; Passeri et al., 2014). Using these factors, a storm surge model of the northern Gulf of Mexico (NGOM) representing present day conditions is modified to characterize the future outlook of the landscape. This adapted model is then used to assess flood risk in terms of the 100-year floodplain surface under SLR scenarios. A suite of hundreds of synthetic storms, derived by JPM-OS (Joint Probability Method - Optimum Sampling), are filtered to obtain the storms necessary to represent the statistically determined 100-year floodplain. The NGOM storm surge model is applied to simulate the synthetic storms and determine, for each storm, the flooding surface and depth, for four SLR scenarios for the year 2100 as prescribed by Parris et al. (2012). The collection of results facilitate the estimation of water surface elevation vs. frequency curves across the floodplain and the statistically defined 100-year floodplain is extracted. This novel method to assess coastal flooding under climate change can be performed across any coastal region worldwide, and results provide awareness of regions vulnerable to extreme flooding in the future.

Observing Storm Surges from Space: A New Opportunity

NASA Astrophysics Data System (ADS)

Han, Guoqi; Ma, Zhimin; Chen, Dake; de Young, Brad; Chen, Nancy

2013-04-01

Coastal tide gauges can be used to monitor variations of a storm surge along the coast, but not in the cross-shelf direction. As a result, the cross-shelf structure of a storm surge has rarely been observed. In this study we focus on Hurricane Igor-induced storm surge off Newfoundland, Canada. Altimetric observations at about 2:30, September 22, 2010 UTC (hours after the passage of Hurricane Igor) reveal prominent cross-shelf variation of sea surface height during the storm passage, including a large nearshore slope and a mid-shelf depression. A significant coastal surge of 1 m derived from satellite altimetry is found to be consistent with tide-gauge measurements at nearby St. John's station. The post-storm sea level variations at St. John's and Argentia are argued to be associated with free equatorward-propagating continental shelf waves (with phase speeds of 11-13 m/s), generated along the northeast Newfoundland coast hours after the storm moved away from St. John's. The cross-shelf e-folding scale of the shelf wave was estimated to be ~100 km. We further show approximate agreement of altimetric and tide-gauge observations in the Gulf of Mexico during Hurricane Katrina (2005) and Isaac (2012). The study for the first time in the literature shows the robustness of satellite altimetry to observe storm surges, complementing tide-gauge observations for the analysis of storm surge characteristics and for the validation and improvement of storm surge models.

Surge of a Complex Glacier System - The Current Surge of the Bering-Bagley Glacier System, Alaska

NASA Astrophysics Data System (ADS)

Herzfeld, U. C.; McDonald, B.; Trantow, T.; Hale, G.; Stachura, M.; Weltman, A.; Sears, T.

2013-12-01

Understanding fast glacier flow and glacial accelerations is important for understanding changes in the cryosphere and ultimately in sea level. Surge-type glaciers are one of four types of fast-flowing glaciers --- the other three being continuously fast-flowing glaciers, fjord glaciers and ice streams --- and the one that has seen the least amount of research. The Bering-Bagley Glacier System, Alaska, the largest glacier system in North America, surged in 2011 and 2012. Velocities decreased towards the end of 2011, while the surge kinematics continued to expand. A new surge phase started in summer and fall 2012. In this paper, we report results from airborne observations collected in September 2011, June/July and September/October 2012 and in 2013. Airborne observations include simultaneously collected laser altimeter data, videographic data, GPS data and photographic data and are complemented by satellite data analysis. Methods range from classic interpretation of imagery to analysis and classification of laser altimeter data and connectionist (neural-net) geostatistical classification of concurrent airborne imagery. Results focus on the characteristics of surge progression in a large and complex glacier system (as opposed to a small glacier with relatively simple geometry). We evaluate changes in surface elevations including mass transfer and sudden drawdowns, crevasse types, accelerations and changes in the supra-glacial and englacial hydrologic system. Supraglacial water in Bering Glacier during Surge, July 2012 Airborne laser altimeter profile across major rift in central Bering Glacier, Sept 2011

Development of Operational Wave-Tide-Storm surges Coupling Prediction System

NASA Astrophysics Data System (ADS)

You, S. H.; Park, S. W.; Kim, J. S.; Kim, K. L.

2009-04-01

The Korean Peninsula is surrounded by the Yellow Sea, East China Sea, and East Sea. This complex oceanographic system includes large tides in the Yellow Sea and seasonally varying monsoon and typhoon events. For Korea's coastal regions, floods caused by wave and storm surges are among the most serious threats. To predict more accurate wave and storm surges, the development of coupling wave-tide-storm surges prediction system is essential. For the time being, wave and storm surges predictions are still made separately in KMA (Korea Meteorological Administration) and most operational institute. However, many researchers have emphasized the effects of tides and storm surges on wind waves and recommended further investigations into the effects of wave-tide-storm surges interactions and coupling module. In Korea, especially, tidal height and current give a great effect on the wave prediction in the Yellow sea where is very high tide and related research is not enough. At present, KMA has operated the wave (RWAM : Regional Wave Model) and storm surges/tide prediction system (STORM : Storm Surges/Tide Operational Model) for ocean forecasting. The RWAM is WAVEWATCH III which is a third generation wave model developed by Tolman (1989). The STORM is based on POM (Princeton Ocean Model, Blumberg and Mellor, 1987). The RWAM and STORM cover the northwestern Pacific Ocean from 115°E to 150°E and from 20°N to 52°N. The horizontal grid intervals are 1/12° in both latitudinal and longitudinal directions. These two operational models are coupled to simulate wave heights for typhoon case. The sea level and current simulated by storm surge model are used for the input of wave model with 3 hour interval. The coupling simulation between wave and storm surge model carried out for Typhoon Nabi (0514), Shanshan(0613) and Nari (0711) which were effected on Korea directly. We simulated significant wave height simulated by wave model and coupling model and compared difference between uncoupling and coupling cases for each typhoon. When the typhoon Nabi hit at southern coast of Kyushu, predicted significant wave height reached over 10 m. The difference of significant wave height between wave and wave-tide-storm surges model represents large variation at the southwestern coast of Korea with about 0.5 m. Other typhoon cases also show similar results with typhoon Nabi case. For typhoon Shanshan case the difference of significant wave height reached up to 0.3 m. When the typhoon Nari was affected in the southern coast of Korea, predicted significant wave height was about 5m. The typhoon Nari case also shows the difference of significant wave height similar with other typhoon cases. Using the observation from ocean buoy operated by KMA, we compared wave information simulated by wave and wave-storm surges coupling model. The significant wave height simulated by wave-tide-storm surges model shows the tidal modulation features in the western and southern coast of Korea. And the difference of significant wave height between two models reached up to 0.5 m. The coupling effect also can be identified in the wave direction, wave period and wave length. In addition, wave spectrum is also changeable due to coupling effect of wave-tide-storm surges model. The development, testing and application of a coupling module in which wave-tide-storm surges are incorporated within the frame of KMA Ocean prediction system, has been considered as a step forward in respect of ocean forecasting. In addition, advanced wave prediction model will be applicable to the effect of ocean in the weather forecasting system. The main purpose of this study is to show how the coupling module developed and to report on a series of experiments dealing with the sensitivities and real case prediction of coupling wave-tide-storm surges prediction system.

14 CFR 33.65 - Surge and stall characteristics.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Surge and stall characteristics. 33.65 Section 33.65 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: AIRCRAFT ENGINES Design and Construction; Turbine Aircraft Engines § 33.65 Surge and...

14 CFR 33.65 - Surge and stall characteristics.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Surge and stall characteristics. 33.65 Section 33.65 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: AIRCRAFT ENGINES Design and Construction; Turbine Aircraft Engines § 33.65 Surge and...

14 CFR 33.65 - Surge and stall characteristics.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Surge and stall characteristics. 33.65 Section 33.65 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: AIRCRAFT ENGINES Design and Construction; Turbine Aircraft Engines § 33.65 Surge and...

Tree Mortality following Prescribed Fire and a Storm Surge Event in Slash Pine ( Pinus elliottii var. densa ) Forests in the Florida Keys, USA

DOE PAGES

Sah, Jay P.; Ross, Michael S.; Snyder, James R.; ...

2010-01-01

In fire-dependent forests, managers are interested in predicting the consequences of prescribed burning on postfire tree mortality. We examined the effects of prescribed fire on tree mortality in Florida Keys pine forests, using a factorial design with understory type, season, and year of burn as factors. We also used logistic regression to model the effects of burn season, fire severity, and tree dimensions on individual tree mortality. Despite limited statistical power due to problems in carrying out the full suite of planned experimental burns, associations with tree and fire variables were observed. Post-fire pine tree mortality was negatively correlated withmore » tree size and positively correlated with char height and percent crown scorch. Unlike post-fire mortality, tree mortality associated with storm surge from Hurricane Wilma was greater in the large size classes. Due to their influence on population structure and fuel dynamics, the size-selective mortality patterns following fire and storm surge have practical importance for using fire as a management tool in Florida Keys pinelands in the future, particularly when the threats to their continued existence from tropical storms and sea level rise are expected to increase.« less

Atlantic hurricane surge response to geoengineering

PubMed Central

Moore, John C.; Grinsted, Aslak; Guo, Xiaoran; Yu, Xiaoyong; Jevrejeva, Svetlana; Rinke, Annette; Cui, Xuefeng; Kravitz, Ben; Lenton, Andrew; Watanabe, Shingo; Ji, Duoying

2015-01-01

Devastating floods due to Atlantic hurricanes are relatively rare events. However, the frequency of the most intense storms is likely to increase with rises in sea surface temperatures. Geoengineering by stratospheric sulfate aerosol injection cools the tropics relative to the polar regions, including the hurricane Main Development Region in the Atlantic, suggesting that geoengineering may mitigate hurricanes. We examine this hypothesis using eight earth system model simulations of climate under the Geoengineering Model Intercomparison Project (GeoMIP) G3 and G4 schemes that use stratospheric aerosols to reduce the radiative forcing under the Representative Concentration Pathway (RCP) 4.5 scenario. Global mean temperature increases are greatly ameliorated by geoengineering, and tropical temperature increases are at most half of those temperature increases in the RCP4.5. However, sulfate injection would have to double (to nearly 10 teragrams of SO2 per year) between 2020 and 2070 to balance the RCP4.5, approximately the equivalent of a 1991 Pinatubo eruption every 2 y, with consequent implications for stratospheric ozone. We project changes in storm frequencies using a temperature-dependent generalized extreme value statistical model calibrated by historical storm surges and observed temperatures since 1923. The number of storm surge events as big as the one caused by the 2005 Katrina hurricane are reduced by about 50% compared with no geoengineering, but this reduction is only marginally statistically significant. Nevertheless, when sea level rise differences in 2070 between the RCP4.5 and geoengineering are factored into coastal flood risk, we find that expected flood levels are reduced by about 40 cm for 5-y events and about halved for 50-y surges. PMID:26504210

Analysis and simulation of propagule dispersal and salinity intrusion from storm surge on the movement of a marsh–mangrove ecotone in South Florida

USGS Publications Warehouse

Jiang, Jiang; DeAngelis, Donald L.; Anderson, Gordon H.; Smith, Thomas J.

2014-01-01

Coastal mangrove–freshwater marsh ecotones of the Everglades represent transitions between marine salt-tolerant halophytic and freshwater salt-intolerant glycophytic communities. It is hypothesized here that a self-reinforcing feedback, termed a “vegetation switch,” between vegetation and soil salinity, helps maintain the sharp mangrove–marsh ecotone. A general theoretical implication of the switch mechanism is that the ecotone will be stable to small disturbances but vulnerable to rapid regime shifts from large disturbances, such as storm surges, which could cause large spatial displacements of the ecotone. We develop a simulation model to describe the vegetation switch mechanism. The model couples vegetation dynamics and hydrologic processes. The key factors in the model are the amount of salt-water intrusion into the freshwater wetland and the passive transport of mangrove (e.g., Rhizophora mangle) viviparous seeds or propagules. Results from the model simulations indicate that a regime shift from freshwater marsh to mangroves is sensitive to the duration of soil salinization through storm surge overwash and to the density of mangrove propagules or seedlings transported into the marsh. We parameterized our model with empirical hydrologic data collected from the period 2000–2010 at one mangrove–marsh ecotone location in southwestern Florida to forecast possible long-term effects of Hurricane Wilma (24 October 2005). The model indicated that the effects of that storm surge were too weak to trigger a regime shift at the sites we studied, 50 km south of the Hurricane Wilma eyewall, but simulations with more severe artificial disturbances were capable of causing substantial regime shifts.

Primary treatment regimen and diabetes insipidus as predictors of health outcomes in adults with childhood-onset craniopharyngioma.

PubMed

Yuen, Kevin C J; Kołtowska-Häggström, Maria; Cook, David M; Fox, Janet L; Jönsson, Peter J; Geffner, Mitchell E; Abs, Roger

2014-04-01

Craniopharyngiomas are often associated with significant morbidity due to their location and treatment effects. Little is known of the effects of primary treatment regimen and diabetes insipidus (DI), a clinical surrogate of hypothalamic obesity, on health outcomes in adults with childhood-onset craniopharyngioma (COCP). The objective of the study was to examine health outcomes of adults with COCP based on primary treatment regimens and the presence of DI. This study included a retrospective KIMS (Pfizer International Metabolic Database) data analysis of 180 adults with COCP according to the primary treatment regimen [one surgery (1Surg) vs complex treatment regimen (CTrR) of more than 1Surg and/or radiotherapy] and the presence of DI. The majority of COCP patients underwent transcranial surgery (77%) without receiving radiotherapy (84%). Compared with the 1Surg group, more CTrR patients developed visual field defects and ophthalmoplegia (all P < .01). Compared with patients without DI, those with DI had higher rates of anterior pituitary hormone deficits, body mass index, and fat mass (all P < .01). By contrast, fasting glucose, hemoglobin A1c, lipid panel, and quality of life were comparable among 1Surg vs CTrR patients, and patients with vs without DI. Regardless of primary treatment received, the presence of DI in either group was associated with higher rates of anterior pituitary hormone deficits and obesity. CTrR and DI predicted health outcomes differently. CTrR predisposed to the development of visual dysfunction, whereas DI was associated with higher rates of anterior pituitary dysfunction and weight gain. Higher body mass index and fat mass in patients with DI further implicate the role of hypothalamic damage as an important causal factor of obesity in these patients.

Modeling the impact of growth and leptin deficits on the neuronal regulation of blood pressure.

PubMed

Steinbrekera, Baiba; Roghair, Robert

2016-11-01

The risk of hypertension is increased by intrauterine growth restriction (IUGR) and preterm birth. In the search for modifiable etiologies for this life-threatening cardiovascular morbidity, a number of pathways have been investigated, including excessive glucocorticoid exposure, nutritional deficiency and aberration in sex hormone levels. As a neurotrophic hormone that is intimately involved in the cardiovascular regulation and whose levels are influenced by glucocorticoids, nutritional status and sex hormones, leptin has emerged as a putative etiologic and thus a therapeutic agent. As a product of maternal and late fetal adipocytes and the placenta, circulating leptin typically surges late in gestation and declines after delivery until the infant consumes sufficient leptin-containing breast milk or accrues sufficient leptin-secreting adipose tissue to reestablish the circulating levels. The leptin deficiency seen in IUGR infants is a multifactorial manifestation of placental insufficiency, exaggerated glucocorticoid exposure and fetal adipose deficit. The preterm infant suffers from the same cascade of events, including separation from the placenta, antenatal steroid exposure and persistently underdeveloped adipose depots. Preterm infants remain leptin deficient beyond term gestation, rendering them susceptible to neurodevelopmental impairment and subsequent cardiovascular dysregulation. This pathologic pathway is efficiently modeled by placing neonatal mice into atypically large litters, thereby recapitulating the perinatal growth restriction-adult hypertension phenotype. In this model, neonatal leptin supplementation restores the physiologic leptin surge, attenuates the leptin-triggered sympathetic activation in adulthood and prevents leptin- or stress-evoked hypertension. Further pathway interrogation and clinical translation are needed to fully test the therapeutic potential of perinatal leptin supplementation. © 2016 Society for Endocrinology.

Modeling the Impact of Growth and Leptin Deficits on the Neuronal Regulation of Blood Pressure

PubMed Central

Steinbrekera, Baiba; Roghair, Robert

2016-01-01

The risk of hypertension is increased by intrauterine growth restriction (IUGR) and preterm birth. In the search for modifiable etiologies for this life-threatening cardiovascular morbidity, a number of pathways have been investigated, including excessive glucocorticoid exposure, nutritional deficiency, and aberration in sex hormone levels. As a neurotrophic hormone intimately involved in cardiovascular regulation whose levels are influenced by glucocorticoids, nutritional status and sex hormones, leptin has emerged as a putative etiologic and thus therapeutic agent. As a product of maternal and late fetal adipocytes as well as the placenta, circulating leptin typically surges late in gestation and declines following delivery until the infant consumes sufficient leptin-containing breast milk or accrues sufficient leptin-secreting adipose tissue to reestablish circulating levels. The leptin deficiency seen in IUGR infants is a multifactorial manifestation of placental insufficiency, exaggerated glucocorticoid exposure and fetal adipose deficit. The preterm infant suffers from the same cascade of events, including separation from the placenta, antenatal steroid exposure and persistently underdeveloped adipose depots. Preterm infants remain leptin deficient beyond term gestation, rendering them susceptible to neurodevelopmental impairment and subsequent cardiovascular dysregulation. This pathologic pathway is efficiently modeled by placing neonatal mice into atypically large litters, thereby recapitulating the perinatal growth restriction-adult hypertension phenotype. In this model, neonatal leptin supplementation restores the physiologic leptin surge, attenuates leptin-triggered sympathetic activation in adulthood and prevents leptin- or stress-evoked hypertension. Further pathway interrogation and clinical translation are needed to fully test the therapeutic potential of perinatal leptin supplementation. PMID:27613336

Potential Hydrodynamic Loads on Coastal Bridges in the Greater New York Area due to Extreme Storm Surge and Wave

DOT National Transportation Integrated Search

2018-04-18

This project makes a computer modeling study on vulnerability of coastal bridges in New York City (NYC) metropolitan region to storm surges and waves. Prediction is made for potential surges and waves in the region and consequent hydrodynamic load an...

Development of wave and surge atlas for the design and protection of coastal bridges in South Louisiana : [research project capsule].

DOT National Transportation Integrated Search

2015-03-01

The recently completed Louisiana Department of Transportation and Development : (DOTD) Storm Surge and Wave Atlas contains signi cant hydraulic information that will : be useful in analyzing storm surge and wave forces on existing and new coastal ...

Coastal Storm Surge Analysis: Storm Surge Results. Report 5: Intermediate Submission No. 3

DTIC Science & Technology

2013-11-01

Vickery, P., D. Wadhera, A. Cox, V. Cardone , J. Hanson, and B. Blanton. 2012. Coastal storm surge analysis: Storm forcing (Intermediate Submission No...CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) Jeffrey L. Hanson, Michael F. Forte, Brian Blanton

76 FR 15315 - Agency Forms Undergoing Paperwork Reduction Act Review

Federal Register 2010, 2011, 2012, 2013, 2014

2011-03-21

... threats. Surge is defined as a marked increase in demand for resources such as personnel, space and material. Health care providers manage both routine surge (predictable fluctuations in demand associated with the weekly calendar, for example) as well as unusual surge (larger fluctuations in demand caused...

Influence of potential sea level rise on societal vulnerability to hurricane storm-surge hazards, Sarasota County, Florida

USGS Publications Warehouse

Frazier, T.G.; Wood, N.; Yarnal, B.; Bauer, D.H.

2010-01-01

Although the potential for hurricanes under current climatic conditions continue to threaten coastal communities, there is concern that climate change, specifically potential increases in sea level, could influence the impacts of future hurricanes. To examine the potential effect of sea level rise on community vulnerability to future hurricanes, we assess variations in socioeconomic exposure in Sarasota County, FL, to contemporary hurricane storm-surge hazards and to storm-surge hazards enhanced by sea level rise scenarios. Analysis indicates that significant portions of the population, economic activity, and critical facilities are in contemporary and future hurricane storm-surge hazard zones. The addition of sea level rise to contemporary storm-surge hazard zones effectively causes population and asset (infrastructure, natural resources, etc) exposure to be equal to or greater than what is in the hazard zone of the next higher contemporary Saffir-Simpson hurricane category. There is variability among communities for this increased exposure, with greater increases in socioeconomic exposure due to the addition of sea level rise to storm-surge hazard zones as one progresses south along the shoreline. Analysis of the 2050 comprehensive land use plan suggests efforts to manage future growth in residential, economic and infrastructure development in Sarasota County may increase societal exposure to hurricane storm-surge hazards. ?? 2010 Elsevier Ltd.

Influence of potential sea level rise on societal vulnerability to hurricane storm-surge hazards, Sarasota County, Florida

USGS Publications Warehouse

Frazier, Tim G.; Wood, Nathan; Yarnal, Brent; Bauer, Denise H.

2010-01-01

Although the potential for hurricanes under current climatic conditions continue to threaten coastal communities, there is concern that climate change, specifically potential increases in sea level, could influence the impacts of future hurricanes. To examine the potential effect of sea level rise on community vulnerability to future hurricanes, we assess variations in socioeconomic exposure in Sarasota County, FL, to contemporary hurricane storm-surge hazards and to storm-surge hazards enhanced by sea level rise scenarios. Analysis indicates that significant portions of the population, economic activity, and critical facilities are in contemporary and future hurricane storm-surge hazard zones. The addition of sea level rise to contemporary storm-surge hazard zones effectively causes population and asset (infrastructure, natural resources, etc) exposure to be equal to or greater than what is in the hazard zone of the next higher contemporary Saffir–Simpson hurricane category. There is variability among communities for this increased exposure, with greater increases in socioeconomic exposure due to the addition of sea level rise to storm-surge hazard zones as one progresses south along the shoreline. Analysis of the 2050 comprehensive land use plan suggests efforts to manage future growth in residential, economic and infrastructure development in Sarasota County may increase societal exposure to hurricane storm-surge hazards.

Probabilistic hurricane-induced storm surge hazard assessment in Guadeloupe, Lesser Antilles

NASA Astrophysics Data System (ADS)

Krien, Y.; Dudon, B.; Roger, J.; Zahibo, N.

2015-01-01

Current storm surge hazard maps in the French West Indies are essentially based on simple statistical methods using limited historical data and early low-resolution models which do not take the effect of waves into account. In this paper, we infer new 100 and 1000 year surge levels in Guadeloupe from the numerical modelling of storm surges induced by a large set of synthetic events that are in statistical agreement with features of historical hurricanes in the North Atlantic Basin between 1980 and 2011. Computations are performed using the wave-current coupled model ADCIRC-SWAN with high grid resolutions (up to 40-60 m) in the coastal and wave dissipation areas. This model is validated against observations during past events such as hurricane HUGO (1989). Results are generally found to be in reasonable agreement with past studies in areas where surge is essentially wind-driven, but to differ significantly in coastal regions where the transfer of momentum from waves to the water column constitutes a non-negligible part of the total surge. The methodology, which can be applied to other islands in the Lesser Antilles, allows to obtain storm surge level maps that can be of major interest for coastal planners and decision makers in terms of risk management.

Probabilistic hurricane-induced storm surge hazard assessment in Guadeloupe, Lesser Antilles

NASA Astrophysics Data System (ADS)

Krien, Y.; Dudon, B.; Roger, J.; Zahibo, N.

2015-08-01

Current storm surge hazard maps in the French West Indies are essentially based on simple statistical methods using limited historical data and early low-resolution models which do not take the effect of waves into account. In this paper, we infer new 100-year and 1000-year surge levels in Guadeloupe from the numerical modelling of storm surges induced by a large set of synthetic events that are in statistical agreement with features of historical hurricanes in the North Atlantic Basin between 1980 and 2011. Computations are performed using the wave-current coupled model ADCIRC-SWAN with high grid resolutions (up to 40-60 m) in the coastal and wave dissipation areas. This model is validated against observations during past events such as hurricane HUGO (1989). Results are generally found to be in reasonable agreement with past studies in areas where surge is essentially wind-driven, but found to differ significantly in coastal regions where the transfer of momentum from waves to the water column constitutes a non-negligible part of the total surge. The methodology, which can be applied to other islands in the Lesser Antilles, allows storm surge level maps to be obtained that can be of major interest for coastal planners and decision makers in terms of risk management.

Recurrence intervals for the closure of the Dutch Maeslant surge barrier

NASA Astrophysics Data System (ADS)

van den Brink, Henk W.; de Goederen, Sacha

2017-09-01

The Dutch Maeslant Barrier, a movable surge barrier in the mouth of the river Rhine, closes when there is a surge in the North Sea and the water level in the river at Rotterdam exceeds 3 m above mean sea level. An important aspect of the failure probability is that the barrier might get damaged during a closure and that, within the time needed for repair, a second critical storm surge may occur. With an estimated closure frequency of once in 10 years, the question of how often the barrier has to be closed twice within one month arises.Instead of tackling this problem by the application of statistical models on the (short) observational series, we solve the problem by combining the surge model WAQUA/DCSMv5 with the output of all seasonal forecasts of the European Centre of Medium-Range Weather Forecasting (ECMWF) in the period 1981-2015, whose combination cumulates in a pseudo-observational series of more than 6000 years.We show that the Poisson process model leads to wrong results as it neglects the temporal correlations that are present on daily, weekly and monthly timescales.By counting the number of double events over a threshold of 2.5 m and assuming that the number of events is exponentially related to the threshold, it is found that two closures occur on average once in 150 years within a month, and once in 330 years within a week. The large uncertainty in these recurrence intervals of more than a factor of two is caused by the sensitivity of the results to the Gumbel parameters of the observed record, which are used for bias correction.Sea level rise has a significant impact on the recurrence time for both single and double closures. The recurrence time of single closures doubles with every 18 cm mean sea level rise (assuming that other influences remain unchanged) and double closures double with every 10 cm rise. This implies a 3-14 times higher probability of a double closure for a 15-40 cm sea level rise in 2050 (according to the KNMI climate scenarios).

The incidence of ophthalmopathy after radioiodine therapy for Graves` disease: Prognostic factors and the role of methimazole

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kung, A.W.C.; Cheng, A.

1994-08-01

Radioactive iodine-131 (RAI) has been reported to be associated with a high incidence of development or exacerbation of Graves` ophthalmopathy (GO). This is thought to be associated with a surge of autoantibodies after RAI therapy. The role of methimazole (MMI), which possesses immunomodulatory action, in the prevention of GO was explored by studying 114 patients with Graves` disease. They were assigned randomly to receive either RAI alone or adjunctive antithyroid drugs, which consisted of MMI and L-T{sub 4} as a block-replacement therapy for 12 months and were followed for 2 yr. Thirty-five patients (30.7%) had GO at presentation. Twenty-one (18%)more » patients developed new GO, and six had worsening of preexisting GO. The development of hypothyroidism (P < 0.01) and an elevation of TSH (P < 0.05) were associated with increased risk of development or exacerbation of GO. The chance of development or exacerbation of GO is higher in those with no ophthalmopathy than in those with preexisting GO at presentation (P = 0.002). The incidence of development or exacerbation of GO was similar in the two treatment groups (RAI, 22.8%; adjunctive antithyroid drugs, 23.7%; P = NS). MMI was able to suppress the surge of TSH receptor antibody (TRAB) after RAI, but a surge in TRAB was not of prognostic significance for the development of GO after RAI. Patients who developed or had exacerbation of GO actually had lower TRAB at presentation (P = 0.02). The authors conclude that hypothyroidism with elevated TSH is an important adverse factor for the development or exacerbation of GO, and MMI was unable to prevent the development or exacerbation of GO after RAI. 35 refs., 4 tabs.« less

Attribution of the 1995 and 2006 storm surge events in the southern Baltic Sea

NASA Astrophysics Data System (ADS)

Klehmet, K.; Rockel, B.; von Storch, H.

2016-12-01

In November 1995 and 2006, the German Baltic Sea coast experienced severe storm surge conditions. Exceptional water level heights of about 1.8m above mean sea level were measured at German tide gauges. Extreme event attribution poses unique challenges trying to distinguish the role of anthropogenic influence, as e.g. greenhouse gas emissions or land-use changes, from natural variability. This study, which is part of the EUCLEIA project (EUropean CLimate and weather Events: Interpretation and Attribution, www. eucleia.eu), aims to estimate how the contribution of anthropogenic drivers has altered the probability of single extreme events such as the 1995 and 2006 storm surge events. We explore these aspects using two 7-member ensembles of Hadley Centre Global Environmental Model version 3-A (HadGEM3-A), the atmosphere only component of the HadGEM3, provided by the Met Office Hadley Centre. The ensemble of HadGEM3-A consists of two multi-decadal experiments from 1960-2013 - one with anthropogenic forcing factors and natural forcings representing the actual climate. The second experiment represents the natural climate including only natural forcing factors. These two 7-member ensembles of about 60km spatial resolution are used as atmospheric forcing data to drive the regional ocean model TRIM-NP in order to calculate water level in the Baltic Sea in 12.8km spatial resolution. Findings indicate some limitations of the regional model ensemble to reproduce the magnitude of extreme water levels well. It is tested whether increased spatial resolution of atmospheric forcing fields can improve the representation of Baltic Sea extreme water levels along the coast and thus add value in the attribution analysis.

Factors Leading to Student Veteran Achievement in Community College: A Quantitative Study Utilizing the Community College Survey of Men

ERIC Educational Resources Information Center

De La Garza, Thomas R.

2016-01-01

Student veteran achievement in community college has received increased attention this past decade with the surge in enrollment by returning military personnel and retired veterans. Similar to previous eras, today's student veterans seek post-war educational opportunities at postsecondary institutions. Yet unlike previous student veteran…

The Faculty Factor: Reassessing the American Academy in a Turbulent Era

ERIC Educational Resources Information Center

Finkelstein, Martin J.; Conley, Valerie Martin; Schuster, Jack H.

2016-01-01

Over the past 70 years, the American university has become the global gold standard of excellence in research and graduate education. The unprecedented surge of federal research support of the post-World War II American university paralleled the steady strengthening of the American academic profession itself, which managed to attract the best and…

Language Is a Girlie Thing, Isn't It? A Psycholinguistic Exploration of the L2 Gender Gap

ERIC Educational Resources Information Center

Wucherer, Barbara Verena; Reiterer, Susanne Maria

2018-01-01

Notwithstanding a surge of novel insights into the male/female variable on human behaviour and cognitive functions, the gender factor is still far from being well understood. Pursuing an interdisciplinary approach, informed by neuroscientific research, this study used linguistic and psychological measures to investigate gender differences in the…

How Do We Model Learning at Scale? A Systematic Review of Research on MOOCs

ERIC Educational Resources Information Center

Joksimovic, Srecko; Poquet, Oleksandra; Kovanovic, Vitomir; Dowell, Nia; Mills, Caitlin; Gaševic, Dragan; Dawson, Shane; Graesser, Arthur C.; Brooks, Christopher

2018-01-01

Despite a surge of empirical work on student participation in online learning environments, the causal links between the learning-related factors and processes with the desired learning outcomes remain unexplored. This study presents a systematic literature review of approaches to model learning in Massive Open Online Courses offering an analysis…

Assessment of the Temporal Evolution of Storm Surge via Land to Water Isopleths in Coastal Louisiana

NASA Astrophysics Data System (ADS)

Siverd, C. G.; Hagen, S. C.; Bilskie, M. V.; Braud, D.; Gao, S.; Peele, H.; Twilley, R.

2017-12-01

The low-lying coastal Louisiana deltaic landscape features an intricate system of fragmented wetlands, natural ridges, man-made navigation canals and flood protection infrastructure. Since 1900 and prior to the landfall of Hurricane Katrina in 2005, Louisiana lost approximately 480,000 ha (1,850 sq mi) of coastal wetlands and an additional 20,000 ha (77 sq mi) due to Katrina. This resulted in a total wetland storm protection value loss of USD 28.3 billion and USD 1.1 billion, respectively (Costanza 2008). To investigate the response of hurricane storm surge (e.g. peak water levels, inundation time and extent) through time due to land loss, hydrodynamic models that represent historical eras of the Louisiana coastal landscape were developed. Land:Water (L:W) isopleths (Gagliano 1970, 1971, Twilley 2016) have been calculated along the coast from the Sabine River to the Pearl River. These isopleths were utilized to create a simplified coastal landscape (bathymetry, topography, bottom roughness) representing circa 2010. Similar methodologies are employed with the objective of developing storm surge models that represent the coastal landscape for past eras. The goal is to temporally examine the evolution of storm surge along coastal Louisiana. The isopleths determined to best represent the Louisiana coast as a result of the methodology devised to develop the simple storm surge model for c.2010 are applied in the development of surge models for historical eras c.1930 and c.1970. The ADvaced CIRCulation (ADCIRC) code (Luettich 2004) is used to perform storm surge simulations with a predetermined suite of hurricane wind and pressure forcings. Hydrologic Unit Code 12 (HUC12) sub-watersheds provide geographical bounds to quantify mean maximum water surface elevations (WSEs), volume of inundation, and area of inundation. HUC12 sub-watersheds also provide a means to compare/contrast these quantified surge parameters on a HUC12-by-HUC12 basis for the c.1930, c.1970 and c.2010 eras. Results will provide insight into how storm surge has evolved in coastal Louisiana from 1930 to 2010 and assist to inform policy makers of regions with temporally accelerating storm surge.

Improved water-level forecasting for the Northwest European Shelf and North Sea through direct modelling of tide, surge and non-linear interaction

NASA Astrophysics Data System (ADS)

Zijl, Firmijn; Verlaan, Martin; Gerritsen, Herman

2013-07-01

In real-time operational coastal forecasting systems for the northwest European shelf, the representation accuracy of tide-surge models commonly suffers from insufficiently accurate tidal representation, especially in shallow near-shore areas with complex bathymetry and geometry. Therefore, in conventional operational systems, the surge component from numerical model simulations is used, while the harmonically predicted tide, accurately known from harmonic analysis of tide gauge measurements, is added to forecast the full water-level signal at tide gauge locations. Although there are errors associated with this so-called astronomical correction (e.g. because of the assumption of linearity of tide and surge), for current operational models, astronomical correction has nevertheless been shown to increase the representation accuracy of the full water-level signal. The simulated modulation of the surge through non-linear tide-surge interaction is affected by the poor representation of the tide signal in the tide-surge model, which astronomical correction does not improve. Furthermore, astronomical correction can only be applied to locations where the astronomic tide is known through a harmonic analysis of in situ measurements at tide gauge stations. This provides a strong motivation to improve both tide and surge representation of numerical models used in forecasting. In the present paper, we propose a new generation tide-surge model for the northwest European Shelf (DCSMv6). This is the first application on this scale in which the tidal representation is such that astronomical correction no longer improves the accuracy of the total water-level representation and where, consequently, the straightforward direct model forecasting of total water levels is better. The methodology applied to improve both tide and surge representation of the model is discussed, with emphasis on the use of satellite altimeter data and data assimilation techniques for reducing parameter uncertainty. Historic DCSMv6 model simulations are compared against shelf wide observations for a full calendar year. For a selection of stations, these results are compared to those with astronomical correction, which confirms that the tide representation in coastal regions has sufficient accuracy, and that forecasting total water levels directly yields superior results.

Optical dating of late Holocene storm surges from Schokland (Noordoostpolder, the Netherlands)

NASA Astrophysics Data System (ADS)

van den Biggelaar, Don; Kluiving, Sjoerd; van Balen, Roland; Kasse, Cronelils; Troelstra, Simon; Prins, Maarten; Wallinga, Jakob; Versendaal, Alice

2015-04-01

Storm surges have a major impact on land use and human habitation in coastal regions. Our understanding of this impact can be improved by correlating long-term historical storm records with sedimentary evidence of storm surges, but so far few studies use such an approach. Here we present detailed geological and historical data on late Holocene storm surges from the former island Schokland, located in the northern part of Flevoland (central Netherlands). During the late Holocene, Schokland transformed from a peat area that gradually inundated (~1200 yr ago) via an island in a marine environment (~400 yr ago) to a land-locked island in the reclaimed Province of Flevoland (~70 yr ago). Deposits formed between 1200 and 70 year ago on lower parts of the island, consist of a stacked sequence of clay and sand layers, with the latter being deposited during storm surges. We dated the sandy laminae of late Holocene storm surges in the clay deposit on Schokland to improve the age model of the island's flooding history during the last 1200 years. Samples for dating were obtained from a mechanical core at Schokland. The top of the peat underlying the clay and sand deposits was dated using 14C accelerator mass spectrometry (AMS) of terrestrial plant and seed material. Sandy intervals of the flood deposits were dated using a series of ten quartz OSL ages, which were obtained using state-of-the-art methods to deal with incomplete resetting of the OSL signal. These new dates, together with laboratory analyses on the clay deposit (thermogravimetric analysis, grain-size analyses, foraminifera, bivalves and ostracods) and a literature study show that storm surges had a major impact on both the sedimentary and the anthropogenic history of Schokland. The results show that the stacked clay sequence is younger than expected, indicating either an increasing sedimentation rate or reworking of the clay by storm surges. Furthermore, the results indicate that a correlation can be made between the sedimentary remains of late Holocene storm surges and several major storm surges mentioned in the historical sources that eroded parts of Schokland.

The combined risk of extreme tropical cyclone winds and storm surges along the U.S. Gulf of Mexico Coast

NASA Astrophysics Data System (ADS)

Trepanier, J. C.; Yuan, J.; Jagger, T. H.

2017-03-01

Tropical cyclones, with their nearshore high wind speeds and deep storm surges, frequently strike the United States Gulf of Mexico coastline influencing millions of people and disrupting offshore economic activities. The combined risk of occurrence of tropical cyclone nearshore wind speeds and storm surges is assessed at 22 coastal cities throughout the United States Gulf of Mexico. The models used are extreme value copulas fitted with margins defined by the generalized Pareto distribution or combinations of Weibull, gamma, lognormal, or normal distributions. The statistical relationships between the nearshore wind speed and storm surge are provided for each coastal city prior to the copula model runs using Spearman's rank correlations. The strongest significant relationship between the nearshore wind speed and storm surge exists at Shell Beach, LA (ρ = 0.67), followed by South Padre Island, TX (ρ = 0.64). The extreme value Archimedean copula models for each city then provide return periods for specific nearshore wind speed and storm surge pairs. Of the 22 cities considered, Bay St. Louis, MS, has the shortest return period for a tropical cyclone with at least a 50 ms-1 nearshore wind speed and a 3 m surge (19.5 years, 17.1-23.5). The 90% confidence intervals are created by recalculating the return periods for a fixed set of wind speeds and surge levels using 100 samples of the model parameters. The results of this study can be utilized by policy managers and government officials concerned with coastal populations and economic activity in the Gulf of Mexico.

Thermodynamic and dynamic structure of atmosphere over the east coast of Peninsular Malaysia during the passage of a cold surge

NASA Astrophysics Data System (ADS)

Samah, Azizan Abu; Babu, C. A.; Varikoden, Hamza; Jayakrishnan, P. R.; Hai, Ooi See

2016-08-01

An intense field observation was carried out for a better understanding of cold surge features over Peninsular Malaysia during the winter monsoon season. The study utilizes vertical profiles of temperature, humidity and wind at high vertical and temporal resolution over Kota Bharu, situated in the east coast of Peninsular Malaysia. LCL were elevated during the passage of the cold surge as the relative humidity values decreased during the passage of cold surge. Level of Free Convection were below 800 hPa and equilibrium levels were close to the LFC in most of the cases. Convective available potential energy and convection inhibition energy values were small during most of the observations. Absence of local heating and instability mechanism are responsible for the peculiar thermodynamic structure during the passage of the cold surge. The wind in the lower atmosphere became northeasterly and was strong during the entire cold surge period. A slight increase in temperature near the surface and a drop in temperature just above the surface were marked by the passage of the cold surge. A remarkable increase in specific humidity was observed between 970 and 900 hPa during the cold surge period. Further, synoptic scale features were analyzed to identify the mechanism responsible for heavy rainfall. Low level convergence, upper level divergence and cyclonic vorticity prevailed over the region during the heavy rainfall event. Dynamic structure of the atmosphere as part of the organized convection associated with the winter monsoon was responsible for the vertical lifting and subsequent rainfall.

Predicting typhoon-induced storm surge tide with a two-dimensional hydrodynamic model and artificial neural network model

NASA Astrophysics Data System (ADS)

Chen, W.-B.; Liu, W.-C.; Hsu, M.-H.

2012-12-01

Precise predictions of storm surges during typhoon events have the necessity for disaster prevention in coastal seas. This paper explores an artificial neural network (ANN) model, including the back propagation neural network (BPNN) and adaptive neuro-fuzzy inference system (ANFIS) algorithms used to correct poor calculations with a two-dimensional hydrodynamic model in predicting storm surge height during typhoon events. The two-dimensional model has a fine horizontal resolution and considers the interaction between storm surges and astronomical tides, which can be applied for describing the complicated physical properties of storm surges along the east coast of Taiwan. The model is driven by the tidal elevation at the open boundaries using a global ocean tidal model and is forced by the meteorological conditions using a cyclone model. The simulated results of the hydrodynamic model indicate that this model fails to predict storm surge height during the model calibration and verification phases as typhoons approached the east coast of Taiwan. The BPNN model can reproduce the astronomical tide level but fails to modify the prediction of the storm surge tide level. The ANFIS model satisfactorily predicts both the astronomical tide level and the storm surge height during the training and verification phases and exhibits the lowest values of mean absolute error and root-mean-square error compared to the simulated results at the different stations using the hydrodynamic model and the BPNN model. Comparison results showed that the ANFIS techniques could be successfully applied in predicting water levels along the east coastal of Taiwan during typhoon events.

On the Importance of the Nonequilibrium Ionization of Si IV and O IV and the Line of Sight in Solar Surges

NASA Astrophysics Data System (ADS)

Nóbrega-Siverio, D.; Moreno-Insertis, F.; Martínez-Sykora, J.

2018-05-01

Surges are ubiquitous cool ejections in the solar atmosphere that often appear associated with transient phenomena like UV bursts or coronal jets. Recent observations from the Interface Region Imaging Spectrograph show that surges, although traditionally related to chromospheric lines, can exhibit enhanced emission in Si IV with brighter spectral profiles than for the average transition region (TR). In this paper, we explain why surges are natural sites to show enhanced emissivity in TR lines. We performed 2.5D radiative-MHD numerical experiments using the Bifrost code including the nonequilibrium (NEQ) ionization of silicon and oxygen. A surge is obtained as a by-product of magnetic flux emergence; the TR enveloping the emerged domain is strongly affected by NEQ effects: assuming statistical equilibrium would produce an absence of Si IV and O IV ions in most of the region. Studying the properties of the surge plasma emitting in the Si IV λ1402.77 and O IV λ1401.16 lines, we find that (a) the timescales for the optically thin losses and heat conduction are very short, leading to departures from statistical equilibrium, and (b) the surge emits in Si IV more and has an emissivity ratio of Si IV to O IV larger than a standard TR. Using synthetic spectra, we conclude the importance of line-of-sight effects: given the involved geometry of the surge, the line of sight can cut the emitting layer at small angles and/or cross it multiple times, causing prominent, spatially intermittent brightenings in both Si IV and O IV.

Role of exogenous estrogen in initiation of estrus and induction of an LH surge

USDA-ARS?s Scientific Manuscript database

Among cattle the LH surge that causes ovulation occurs shortly after the onset of a spontaneous estrus. In addition an injection of 100 'g of GnRH can induce an LH surge capable of inducing ovulation. We hypothesized that different preovulatory estradiol profiles would result in different ovulator...

Phase I Report for SERRI Project No. 80037: Investigation of surge and wave reduction by vegetation

USDA-ARS?s Scientific Manuscript database

Surge and waves generated by hurricanes and other severe storms can cause devastating damage of property and loss of life in coastal areas. Vegetation in wetlands, coastal fringes and stream floodplains can reduce storm surge and waves while providing ecological benefits and complementing traditiona...

[Analysis of articles published in Chin J Surg since founded in 1951].

PubMed

Xia, Shuang; Li, Jing

2016-01-01

To discuss the characteristics of the articles published in Chin J Surg from 1951 to 2015. The journals and articles of Acad Surg from 1951 to 1952 and Chin J Surg from 1953 to 2015 were analyzed. The subjects, foundation, basic medical study, international cooperation of the articles were recorded. In 65 years, there were 20 090 academic articles published in Chin J Surg. The proportions of general surgery, orthopedic surgery, thoracocardiac surgery, urology surgery and neurosurgery articles were 34.08%, 17.96%, 13.09%, 11.91% and 5.85%, respectively. There were 14.83% (1 728/11 653) articles receiving foundation, and 9.42% (1 817/19 290) articles reporting basic medical study. There were 14.8% articles from international authors and 119 articles with international cooperation. From 2000 to 2003, 29 articles in original English were published. The coverage of Chin J Surg contains all the fields of surgery. It tends to publish the studies focus on clinical issues.Through reinforcing the content plan and optimizing the show form, the more Chinese surgical research achievements could be shared by the surgeons worldwide.

Base surge in recent volcanic eruptions

USGS Publications Warehouse

Moore, J.G.

1967-01-01

A base surge, first identified at the Bikini thermonuclear undersea explosion, is a ring-shaped basal cloud that sweeps outward as a density flow from the base of a vertical explosion column. Base surges are also common in shallow underground test explosions and are formed by expanding gases which first vent vertically and then with continued expansion rush over the crater lip (represented by a large solitary wave in an underwater explosion), tear ejecta from it, and feed a gas-charged density flow, which is the surge cloud. This horizontally moving cloud commonly has an initial velocity of more than 50 meters per second and can carry clastic material many kilometers. Base surges are a common feature of many recent shallow, submarine and phreatic volcanic eruptions. They transport ash, mud, lapilli, and blocks with great velocity and commonly sandblast and knock down trees and houses, coat the blast side with mud, and deposit ejecta at distances beyond the limits of throw-out trajectories. Close to the eruption center, the base surge can erode radial channels and deposit material with dune-type bedding. ?? 1967 Stabilimento Tipografico Francesco Giannini & Figli.

Top-down or bottom-up? Assessing crevassing directions on surging glaciers and developments for physically testing glacier crevassing models.

NASA Astrophysics Data System (ADS)

Rea, B.; Evans, D. J. A.; Benn, D. I.; Brennan, A. J.

2012-04-01

Networks of crevasse squeeze ridges (CSRs) preserved on the forelands of many surging glaciers attest to extensive full-depth crevassing. Full-depth connections have been inferred from turbid water up-welling in crevasses and the formation of concertina eskers however, it has not been clearly established if the crevasses formed from the top-down or the bottom-up. A Linear Elastic Fracture Mechanics (LEFM) approach is used to determine the likely propagation direction for Mode I crevasses on seven surging glaciers. Results indicate that, the high extensional surface strain rates are insufficient to promote top-down full-depth crevasses but have sufficient magnitude to penetrate to depths of 4-12 m, explaining the extensive surface breakup accompanying glacier surges. Top-down, full-depth crevassing is only possible when water depth approaches 97% of the crevasse depth. However, the provision of sufficient meltwater is problematic due to the aforementioned extensive shallow surface crevassing. Full-depth, bottom-up crevassing can occur provided basal water pressures are in excess of 80-90% of flotation which is the default for surging and on occasion water pressures may even become artesian. Therefore CSRs, found across many surging glacier forelands and ice margins most likely result from the infilling of basal crevasses formed, for the most part, by bottom-up hydrofracturing. Despite the importance of crevassing for meltwater routing and calving dynamics physically testing numerical crevassing models remains problematic due to technological limitations, changing stress regimes and difficulties associated with working in crevasse zones on glaciers. Mapping of CSR spacing and matching to surface crevasse patterns can facilitate quantitative comparison between the LEFM model and observed basal crevasses provided ice dynamics are known. However, assessing full-depth top-down crevasse propagation is much harder to monitor in the field and no geomorphological record is preserved. An alternative approach is provided by geotechnical centrifuge modelling. By testing scaled models in an enhanced 'gravity' field real-world (prototype) stress conditions can be reproduced which is crucial for problems governed by self-weight stresses, of which glacier crevassing is one. Scaling relationships have been established for stress intensity factors - KI which are key to determining crevasse penetration such that KIp = √N KIm (p = prototype and m = model). Operating specifications of the University of Dundee geotechnical centrifuge (100g) will allow the testing of scaled models equivalent to prototype glaciers of 50 m thickness in order to provide a physical test of the LEFM top-down crevassing model.

Designsafe-Ci a Cyberinfrastructure for Natural Hazard Simulation and Data

NASA Astrophysics Data System (ADS)

Dawson, C.; Rathje, E.; Stanzione, D.; Padgett, J.; Pinelli, J. P.

2017-12-01

DesignSafe is the web-based research platform of the Natural Hazards Engineering Research Infrastructure (NHERI) network that provides the computational tools needed to manage and analyze critical data for natural hazards research, with wind and storm surge related hazards being a primary focus. One of the simulation tools under DesignSafe is the Advanced Circulation (ADCIRC) model, a coastal ocean model used in storm surge analysis. ADCIRC is an unstructured, finite element model with high resolution capabilities for studying storm surge impacts, and has long been used in storm surge hind-casting and forecasting. In this talk, we will demonstrate the use of ADCIRC within the DesignSafe platform and its use for forecasting Hurricane Harvey. We will also demonstrate how to analyze, visualize and archive critical storm surge related data within DesignSafe.

Secondary Surge Capacity: A Framework for Understanding Long-Term Access to Primary Care for Medically Vulnerable Populations in Disaster Recovery

PubMed Central

Brock-Martin, Amy; Karmaus, Wilfried; Svendsen, Erik R.

2012-01-01

Disasters create a secondary surge in casualties because of the sudden increased need for long-term health care. Surging demands for medical care after a disaster place excess strain on an overtaxed health care system operating at maximum or reduced capacity. We have applied a health services use model to identify areas of vulnerability that perpetuate health disparities for at-risk populations seeking care after a disaster. We have proposed a framework to understand the role of the medical system in modifying the health impact of the secondary surge on vulnerable populations. Baseline assessment of existing needs and the anticipation of ballooning chronic health care needs following the acute response for at-risk populations are overlooked vulnerability gaps in national surge capacity plans. PMID:23078479

Modeling Tropical Cyclone Storm Surge and Wind Induced Risk Along the Bay of Bengal Coastline Using a Statistical Copula

NASA Astrophysics Data System (ADS)

Bushra, N.; Trepanier, J. C.; Rohli, R. V.

2017-12-01

High winds, torrential rain, and storm surges from tropical cyclones (TCs) cause massive destruction to property and cost the lives of many people. The coastline of the Bay of Bengal (BoB) ranks as one of the most susceptible to TC storm surges in the world due to low-lying elevation and a high frequency of occurrence. Bangladesh suffers the most due to its geographical setting and population density. Various models have been developed to predict storm surge in this region but none of them quantify statistical risk with empirical data. This study describes the relationship and dependency between empirical TC storm surge and peak reported wind speed at the BoB using a bivariate statistical copula and data from 1885-2011. An Archimedean, Gumbel copula with margins defined by the empirical distributions is specified as the most appropriate choice for the BoB. The model provides return periods for pairs of TC storm surge and peak wind along the BoB coastline. The BoB can expect a TC with peak reported winds of at least 24 m s-1 and surge heights of at least 4.0 m, on average, once every 3.2 years, with a quartile pointwise confidence interval of 2.7-3.8 years. In addition, the BoB can expect peak reported winds of 62 m s-1 and surge heights of at least 8.0 m, on average, once every 115.4 years, with a quartile pointwise confidence interval of 55.8-381.1 years. The purpose of the analysis is to increase the understanding of these dangerous TC characteristics to reduce fatalities and monetary losses into the future. Application of the copula will mitigate future threats of storm surge impacts on coastal communities of the BoB.

Purple Pitcher Plant (Sarracenia rosea) Dieback and Partial Community Disassembly following Experimental Storm Surge in a Coastal Pitcher Plant Bog

PubMed Central

Abbott, Matthew J.; Battaglia, Loretta L.

2015-01-01

Sea-level rise and frequent intense hurricanes associated with climate change will result in recurrent flooding of inland systems such as Gulf Coastal pitcher plant bogs by storm surges. These surges can transport salt water and sediment to freshwater bogs, greatly affecting their biological integrity. Purple pitcher plants (Sarracenia rosea) are Gulf Coast pitcher plant bog inhabitants that could be at a disadvantage under this scenario because their pitcher morphology may leave them prone to collection of saline water and sediment after a surge. We investigated the effects of storm surge water salinity and sediment type on S. rosea vitality, plant community structure, and bog soil-water conductivity. Plots (containing ≥1 ramet of S. rosea) were experimentally flooded with fresh or saline water crossed with one of three sediment types (local, foreign, or no sediment). There were no treatment effects on soil-water conductivity; nevertheless, direct exposure to saline water resulted in significantly lower S. rosea cover until the following season when a prescribed fire and regional drought contributed to the decline of all the S. rosea to near zero percent cover. There were also significant differences in plant community structure between treatments over time, reflecting how numerous species increased in abundance and a few species decreased in abundance. However, in contrast to S. rosea, most of the other species in the community appeared resilient to the effects of storm surge. Thus, although the community may be somewhat affected by storm surge, those few species that are particularly sensitive to the storm surge disturbance will likely drop out of the community and be replaced by more resilient species. Depending on the longevity of these biological legacies, Gulf Coastal pitcher plant bogs may be incapable of fully recovering if they become exposed to storm surge more frequently due to climate change. PMID:25874369

Purple pitcher plant (Sarracenia rosea) Dieback and partial community disassembly following experimental storm surge in a coastal pitcher plant bog.

PubMed

Abbott, Matthew J; Battaglia, Loretta L

2015-01-01

Sea-level rise and frequent intense hurricanes associated with climate change will result in recurrent flooding of inland systems such as Gulf Coastal pitcher plant bogs by storm surges. These surges can transport salt water and sediment to freshwater bogs, greatly affecting their biological integrity. Purple pitcher plants (Sarracenia rosea) are Gulf Coast pitcher plant bog inhabitants that could be at a disadvantage under this scenario because their pitcher morphology may leave them prone to collection of saline water and sediment after a surge. We investigated the effects of storm surge water salinity and sediment type on S. rosea vitality, plant community structure, and bog soil-water conductivity. Plots (containing ≥1 ramet of S. rosea) were experimentally flooded with fresh or saline water crossed with one of three sediment types (local, foreign, or no sediment). There were no treatment effects on soil-water conductivity; nevertheless, direct exposure to saline water resulted in significantly lower S. rosea cover until the following season when a prescribed fire and regional drought contributed to the decline of all the S. rosea to near zero percent cover. There were also significant differences in plant community structure between treatments over time, reflecting how numerous species increased in abundance and a few species decreased in abundance. However, in contrast to S. rosea, most of the other species in the community appeared resilient to the effects of storm surge. Thus, although the community may be somewhat affected by storm surge, those few species that are particularly sensitive to the storm surge disturbance will likely drop out of the community and be replaced by more resilient species. Depending on the longevity of these biological legacies, Gulf Coastal pitcher plant bogs may be incapable of fully recovering if they become exposed to storm surge more frequently due to climate change.

Controlled Ovarian Hyperstimulation with Intrauterine Insemination Is More Successful After r-hCG Administration Than Spontaneous LH Surge.

PubMed

Taerk, Evan; Hughes, Edward; Greenberg, Cassandra; Neal, Michael; Amin, Shilpa; Faghih, Mehrnoosh; Karnis, Megan

2017-01-01

The purpose of this study was to evaluate whether clinical pregnancy rate is affected by timing intrauterine insemination (IUI) according to serum LH surge, r-hCG trigger, or a combination of LH surge and r-hCG trigger in controlled ovarian hyperstimulation (COH) cycles for patients with a variety of infertility etiologies. The last 365 consecutive COH-IUI cycles performed at ONE Fertility Burlington in 2014 were reviewed and categorized according to method of IUI timing. Associations between categorical variables were analyzed using a combination of Chi-square and Fisher's Exact tests, and between continuous variables using independent sample t-tests and logistic regression to a level of significance of p<0.05. The overall clinical pregnancy rate in this sample was 18.1% (66/365). Administration of r-hCG prior to IUI resulted in a higher clinical pregnancy rate compared with spontaneous serum LH surge: 18.2% vs . 5.8%, p=0.012. Patients in whom r-hCG was administered concomitantly with a serum LH surge had a higher clinical pregnancy than the r-hCG trigger group (30.8% vs . 18.2%, p=0.004) and LH surge group (30.8% vs . 5.8%, p<0.001). A sub-group analysis revealed that patients receiving r-FSH, rather than clomiphene or letrozole, had a significantly higher clinical pregnancy rate after r-hCG trigger as compared to the LH surge group (21.7% vs . 2.1%, p=0.01). In subfertile couples undergoing COH-IUI, r-hCG administration was associated with an increased clinical pregnancy rate compared with spontaneous serum LH surge. When r-hCG was administered concomitantly with a serum LH surge, this benefit was amplified. The effect appears to be of particular importance in r-FSH-medicated cycles.

Liftoff of the 18 May 1980 surge of Mount St. Helens (USA) and the deposits left behind

NASA Astrophysics Data System (ADS)

Gardner, James E.; Andrews, Benjamin J.; Dennen, Robert

2017-01-01

The distance that ground-hugging pyroclastic density currents travel is limited partly by when they reverse buoyancy and liftoff into the atmosphere. It is not clear, however, what deposits are left behind by lofting flows. One current that was seen to liftoff was the surge erupted from Mount St. Helens on the morning of 18 May 1980. Before lofting, it had leveled a large area of thick forest (the blowdown zone). The outer edge of the devastated area—where trees were scorched but left standing (the scorched zone)—is where the surge is thought to have lifted off. Deposits in the outer parts of the blowdown and in the scorched zone were examined at 32 sites. The important finding is that the laterally moving surge traveled through the scorched zone, and hence, the change in tree damage does not mark the runout distance of the surge. Buoyancy reversal and liftoff are thus not preserved in the deposits where the surge lofted upwards. We propose, based on interpretation of eyewitness accounts and the impacts of the surge on trees and vehicles, that the surge consisted of a faster, dilute "overcurrent" and a slower "undercurrent," where most of the mass (and heat) was retained. Reasonable estimates for flow density and velocity show that dynamic pressure of the surge (i.e., its ability to topple trees) peaked near the base of the overcurrent. We propose that where the overcurrent began to liftoff, the height of peak dynamic pressure rose above the trees and stopped toppling them. The slower undercurrent continued forward, however, scorching trees, but lacked the dynamic pressure needed to topple them. Grain-size variations argue that it slowed from ˜30 m s-1 when it entered the scorched zone to ˜3 m s-1 at the far end.

Runout distance and dynamic pressure of pyroclastic density currents: Evidence from 18 May 1980 blast surge of Mount St. Helens

NASA Astrophysics Data System (ADS)

Gardner, J. E.; Andrews, B. J.

2016-12-01

Pyroclastic density currents (flows and surges) are one of the most deadly hazards associated with volcanic eruptions. Understanding what controls how far such currents will travel, and how their dynamic pressure evolves, could help mitigate their hazards. The distance a ground hugging, pyroclastic density current travels is partly limited by when it reverses buoyancy and lifts off into the atmosphere. The 1980 blast surge of Mount St. Helens offers an example of a current seen to lift off. Before lofting, it had traveled up to 20 km and leveled more than 600 km3 of thick forest (the blowdown zone). The outer edge of the devastated area - where burned trees that were left standing (the singe zone) - is where the surge is thought to have lifted off. We recently examined deposits in the outer parts of the blowdown and in the singe zone at 32 sites. The important finding is that the laterally moving surge travelled into the singe zone, and hence the change in tree damage does not mark the run out distance of the ground hugging surge. Eyewitness accounts and impacts on trees and vehicles reveal that the surge consisted of a fast, dilute "overcurrent" and a slower "undercurrent", where most of the mass (and heat) was retained. Reasonable estimates for flow density and velocity show that dynamic pressure of the surge (i.e., its ability to topple trees) peaked near the base of the overcurrent. We propose that when the overcurrent began to lift off, the height of peak dynamic pressure rose above the trees and stopped toppling them. The slower undercurrent continued forward, burning trees but it lacked the dynamic pressure needed to topple them. Grain-size variations argue that it slowed from 30 m/s when it entered the singe zone to 3 m/s at the far end. Buoyancy reversal and liftoff are thus not preserved in the deposits where the surge lofted upwards.

The Effect of Coastal Development on Storm Surge Flooding in Biscayne Bay, Florida, USA (Invited)

NASA Astrophysics Data System (ADS)

Zhang, K.; Liu, H.; Li, Y.

2013-12-01

Barrier islands and associated bays along the Atlantic and Gulf Coasts are a favorite place for both living and visiting. Many of them are vulnerable to storm surge flooding because of low elevations and constantly being subjected to the impacts of storms. The population increase and urban development along the barrier coast have altered the shoreline configuration, resulting in a dramatic change in the coastal flooding pattern in some areas. Here we present such a case based on numerical simulations of storm surge flooding caused by the1926 hurricane in the densely populated area surrounding Biscayne Bay in Miami, Florida. The construction of harbor and navigation channels, and the development of real estate and the roads connecting islands along Biscayne Bay have changed the geometry of Biscayne Bay since 1910s. Storm surge simulations show that the Port of Miami and Dodge Island constructed by human after 1950 play an important role in changing storm surge inundation pattern along Biscayne Bay. Dodge Island enhances storm surge and increases inundation in the area south of the island, especially at the mouth of Miami River (Downtown of Miami), and reduces storm surge flooding in the area north of the island, especially in Miami Beach. If the Hurricane Miami of 1926 happened today, the flooding area would be reduced by 55% and 20% in the Miami Beach and North Miami areas, respectively. Consequently, it would prevent 400 million of property and 10 thousand people from surge flooding according to 2010 U.S census and 2007 property tax data. Meanwhile, storm water would penetrate further inland south of Dodge Island and increase the flooding area by 25% in the Miami River and Downtown Miami areas. As a result, 200 million of property and five thousand people would be impacted by storm surge.

Development of Inundation Map for Bantayan Island, Cebu Using Delft3D-Flow Storm Surge Simulations of Typhoon Haiyan

NASA Astrophysics Data System (ADS)

Cuadra, Camille; Suarez, John Kenneth; Biton, Nophi Ian; Cabacaba, Krichi May; Lapidez, John Phillip; Santiago, Joy; Mahar Francisco Lagmay, Alfredo; Malano, Vicente

2014-05-01

On average, 20 typhoons enter the Philippine area of responsibility annually, making it vulnerable to different storm hazards. Apart from the frequency of tropical cyclones, the archipelagic nature of the country makes it particularly prone to storm surges. On 08 November 2013, Haiyan, a Category 5 Typhoon with maximum one-minute sustained wind speed of 315 kph, hit the central region of the Philippines. In its path, the howler devastated Bantayan Island, a popular tourist destination. The island is located north of Cebu City, the second largest metropolis of the Philippines in terms of populace. Having been directly hit by Typhoon Haiyan, Bantayan Island was severely damaged by strong winds and storm surges, with more than 11,000 houses totally destroyed while 5,000 more suffered minor damage. The adverse impacts of possible future storm surge events in the island can only be mitigated if hazard maps that depict inundation of the coastal areas of Bantayan are generated. To create such maps, Delft3D-Flow, a hydrodynamic model was used to simulate storm surges. These simulations were made over a 10-m per pixel resolution Digital Elevation Model (DEM) and the General Bathymetric Chart of the Oceans (GEBCO) bathymetry. The results of the coastal inundation model for Typhoon Haiyan's storm surges were validated using data collected from field work and local government reports. The hydrodynamic model of Bantayan was then calibrated using the field data and further simulations were made with varying typhoon tracks. This was done to generate scenarios on the farthest possible inland incursion of storm surges. The output of the study is a detailed storm surge inundation map that depicts safe zones for development of infrastructure near coastal areas and for construction of coastal protection structures. The storm surge inundation map can also be used as basis for disaster preparedness plans of coastal communities threatened by approaching typhoons.

The Danger of Deja Vu: Why the Iraq Surge is Not a Lesson for Afghanistan

DTIC Science & Technology

2010-01-01

JAN 2010 2. REPORT TYPE 3. DATES COVERED 00-12-2009 to 00-01-2010 4. TITLE AND SUBTITLE The danger of deja vu . Why the Iraq surge is not a lesson...of five brigade combat teams — eerily mim- icked the surge number for Iraq. And there was more déjà vu when our senior civilian and military leaders...Department. PERSPECTIVES The danger of déjà vu Why the Iraq surge is not a lesson for Afghanistan BY COL. CHARLES D. ALLEN (RET.) The thing we take hold of

Performance Comparison of the European Storm Surge Models and Chaotic Model in Forecasting Extreme Storm Surges

NASA Astrophysics Data System (ADS)

Siek, M. B.; Solomatine, D. P.

2009-04-01

Storm surge modeling has rapidly developed considerably over the past 30 years. A number of significant advances on operational storm surge models have been implemented and tested, consisting of: refining computational grids, calibrating the model, using a better numerical scheme (i.e. more realistic model physics for air-sea interaction), implementing data assimilation and ensemble model forecasts. This paper addresses the performance comparison between the existing European storm surge models and the recently developed methods of nonlinear dynamics and chaos theory in forecasting storm surge dynamics. The chaotic model is built using adaptive local models based on the dynamical neighbours in the reconstructed phase space of observed time series data. The comparison focused on the model accuracy in forecasting a recently extreme storm surge in the North Sea on November 9th, 2007 that hit the coastlines of several European countries. The combination of a high tide, north-westerly winds exceeding 50 mph and low pressure produced an exceptional storm tide. The tidal level was exceeded 3 meters above normal sea levels. Flood warnings were issued for the east coast of Britain and the entire Dutch coast. The Maeslant barrier's two arc-shaped steel doors in the Europe's biggest port of Rotterdam was closed for the first time since its construction in 1997 due to this storm surge. In comparison to the chaotic model performance, the forecast data from several European physically-based storm surge models were provided from: BSH Germany, DMI Denmark, DNMI Norway, KNMI Netherlands and MUMM Belgium. The performance comparison was made over testing datasets for two periods/conditions: non-stormy period (1-Sep-2007 till 14-Oct-2007) and stormy period (15-Oct-2007 till 20-Nov-2007). A scalar chaotic model with optimized parameters was developed by utilizing an hourly training dataset of observations (11-Sep-2005 till 31-Aug-2007). The comparison results indicated the chaotic model yields better forecasts than the existing European storm surge models. The best performance of European storm surge models for non-storm and storm conditions was achieved by KNMI (with Kalman filter data assimilation) and BSH with errors of 8.95cm and 10.92cm, respectively. Whereas the chaotic model can provide 6 and 48 hours forecasts with errors of 3.10cm and 8.55cm for non-storm condition and 5.04cm and 15.21cm for storm condition, respectively. The chaotic model can provide better forecasts primarily due to the fact that the chaotic model forecasting are estimated by local models which model and identify the similar development of storm surges in the past. In practice, the chaotic model can serve as a reliable and accurate model to support decision-makers in operational ship navigation and flood forecasting.

Assessing storm surge hazard and impact of sea level rise in the Lesser Antilles case study of Martinique

NASA Astrophysics Data System (ADS)

Krien, Yann; Dudon, Bernard; Roger, Jean; Arnaud, Gael; Zahibo, Narcisse

2017-09-01

In the Lesser Antilles, coastal inundations from hurricane-induced storm surges pose a great threat to lives, properties and ecosystems. Assessing current and future storm surge hazards with sufficient spatial resolution is of primary interest to help coastal planners and decision makers develop mitigation and adaptation measures. Here, we use wave-current numerical models and statistical methods to investigate worst case scenarios and 100-year surge levels for the case study of Martinique under present climate or considering a potential sea level rise. Results confirm that the wave setup plays a major role in the Lesser Antilles, where the narrow island shelf impedes the piling-up of large amounts of wind-driven water on the shoreline during extreme events. The radiation stress gradients thus contribute significantly to the total surge - up to 100 % in some cases. The nonlinear interactions of sea level rise (SLR) with bathymetry and topography are generally found to be relatively small in Martinique but can reach several tens of centimeters in low-lying areas where the inundation extent is strongly enhanced compared to present conditions. These findings further emphasize the importance of waves for developing operational storm surge warning systems in the Lesser Antilles and encourage caution when using static methods to assess the impact of sea level rise on storm surge hazard.

The art and science of surge: experience from Israel and the U.S. military.

PubMed

Tadmor, Boaz; McManus, John; Koenig, Kristi L

2006-11-01

In a disaster or mass casualty incident, health care resources may be exceeded and systems may be challenged by unusual requirements. These resources may include pharmaceuticals, supplies, and equipment as well as certain types of academic and administrative expertise. New agencies and decision makers may need to work together in an unfamiliar environment. Furthermore, large numbers of casualties needing treatment, newer therapies required to care for these casualties, and increased workforce and space available for these casualties all contribute to what is often referred to as "surge." Surge capacity in emergency care can be described in technical, scientific terms that are measured by numbers and benchmarks (e.g., beds, patients, and medications) or can take on a more conceptual and abstract form (e.g., decisions, authority, and responsibility). The former may be referred to as the "science" of surge, whereas the latter, an equal if not more important component of surge systems that is more conceptual and abstract, can be considered the "art" of surge. The experiences from Israel and the U.S. military may serve to educate colleagues who may be required to respond or react to an event that taxes the current health care system. This report presents concrete examples of surge capacity strategies used by both Israel and the U.S. military and provides solutions that may be applied to other health care systems when faced with similar situations.

Morning blood pressure surge and arterial stiffness in newly diagnosed hypertensive patients.

PubMed

Kıvrak, Ali; Özbiçer, Süleyman; Kalkan, Gülhan Yüksel; Gür, Mustafa

2017-06-01

We aimed to investigate the relationship between the morning blood pressure (BP) surge and arterial stiffness in patients with newly diagnosed hypertension. Three hundred and twenty four (mean age 51.7 ± 11.4 years) patients who had newly diagnosed hypertension with 24 h ambulatory BP monitoring were enrolled. Parameters of arterial stiffness, pulse wave velocity and augmentation index (Aix) were measured by applanation tonometry and aortic distensibility was calculated by echocardiography. Compared with the other groups, pulse wave velocity, day-night systolic BP (SBP) difference (p < 0.001, for all) and hs-CRP (p = 0.005) were higher in morning BP surge high group. Aortic distensibility values were significantly lower in morning BP surge high group compared to the other groups (p < 0.05, for all). Morning BP surge was found to be independently associated with pulse wave velocity (β = 0.286, p < 0.001), aortic distensibility (β= -0.384, p < 0.001) and day-night SBP difference (β = 0.229, p < 0.001) in multivariate linear regression analysis. We found independent relationship between morning BP surge and arterial stiffness which is a surrogate endpoint for cardiovascular diseases. The inverse relationship between morning BP surge and aortic distensibility and direct relation found in our study is new to the literature.

Evolution of a natural debris flow: In situ measurements of flow dynamics, video imagery, and terrestrial laser scanning

USGS Publications Warehouse

McCoy, S.W.; Kean, J.W.; Coe, J.A.; Staley, D.M.; Wasklewicz, T.A.; Tucker, G.E.

2010-01-01

Many theoretical and laboratory studies have been undertaken to understand debris-flow processes and their associated hazards. However, complete and quantitative data sets from natural debris flows needed for confirmation of these results are limited. We used a novel combination of in situ measurements of debris-flow dynamics, video imagery, and pre- and postflow 2-cm-resolution digital terrain models to study a natural debris-flow event. Our field data constrain the initial and final reach morphology and key flow dynamics. The observed event consisted of multiple surges, each with clear variation of flow properties along the length of the surge. Steep, highly resistant, surge fronts of coarse-grained material without measurable pore-fluid pressure were pushed along by relatively fine-grained and water-rich tails that had a wide range of pore-fluid pressures (some two times greater than hydrostatic). Surges with larger nonequilibrium pore-fluid pressures had longer travel distances. A wide range of travel distances from different surges of similar size indicates that dynamic flow properties are of equal or greater importance than channel properties in determining where a particular surge will stop. Progressive vertical accretion of multiple surges generated the total thickness of mapped debris-flow deposits; nevertheless, deposits had massive, vertically unstratified sedimentological textures. ?? 2010 Geological Society of America.

Typhoon Haiyan-Induced Storm Surge Simulation in Metro Manila Using High-Resolution LiDAR Topographic Data

NASA Astrophysics Data System (ADS)

Santiago, J. T.

2015-12-01

Storm surge is the abnormal rise in sea water over and above astronomical tides due to a forthcoming storm. Developing an early warning system for storm surges is vital due to the high level of hazard they might cause. On 08 November 2013, Typhoon Haiyan generated storm surges that killed over 6,000 people in the central part of the Philippines. The Nationwide Operational Assessment of Hazards under the Department of Science and Technology was tasked to create storm surge hazard maps for the country's coastal areas. The research project aims to generate storm surge hazard maps that can be used for disaster mitigation and planning. As part of the research, the team explored a scenario wherein a tropical cyclone hits the Metro Manila with strength as strong as Typhoon Haiyan. The area was chosen primarily for its political, economic and cultural significance as the country's capital. Using Japan Meteorological Agency Storm Surge model, FLO2D flooding software, LiDAR topographic data, and GIS technology, the effects of a Haiyan-induced tropical cyclone passing through Metro Manila was examined. The population affected, number of affected critical facilities, and potential evacuation sites were identified. The outputs of this study can be used by the authorities as basis for policies that involve disaster risk reduction and management.

Hurricane Sandy's flood frequency increasing from year 1800 to 2100.

PubMed

Lin, Ning; Kopp, Robert E; Horton, Benjamin P; Donnelly, Jeffrey P

2016-10-25

Coastal flood hazard varies in response to changes in storm surge climatology and the sea level. Here we combine probabilistic projections of the sea level and storm surge climatology to estimate the temporal evolution of flood hazard. We find that New York City's flood hazard has increased significantly over the past two centuries and is very likely to increase more sharply over the 21st century. Due to the effect of sea level rise, the return period of Hurricane Sandy's flood height decreased by a factor of ∼3× from year 1800 to 2000 and is estimated to decrease by a further ∼4.4× from 2000 to 2100 under a moderate-emissions pathway. When potential storm climatology change over the 21st century is also accounted for, Sandy's return period is estimated to decrease by ∼3× to 17× from 2000 to 2100.

Hurricane Sandy’s flood frequency increasing from year 1800 to 2100

PubMed Central

Horton, Benjamin P.; Donnelly, Jeffrey P.

2016-01-01

Coastal flood hazard varies in response to changes in storm surge climatology and the sea level. Here we combine probabilistic projections of the sea level and storm surge climatology to estimate the temporal evolution of flood hazard. We find that New York City’s flood hazard has increased significantly over the past two centuries and is very likely to increase more sharply over the 21st century. Due to the effect of sea level rise, the return period of Hurricane Sandy’s flood height decreased by a factor of ∼3× from year 1800 to 2000 and is estimated to decrease by a further ∼4.4× from 2000 to 2100 under a moderate-emissions pathway. When potential storm climatology change over the 21st century is also accounted for, Sandy’s return period is estimated to decrease by ∼3× to 17× from 2000 to 2100. PMID:27790992

Two-dimensional frequency-domain acoustic full-waveform inversion with rugged topography

NASA Astrophysics Data System (ADS)

Zhang, Qian-Jiang; Dai, Shi-Kun; Chen, Long-Wei; Li, Kun; Zhao, Dong-Dong; Huang, Xing-Xing

2015-09-01

We studied finite-element-method-based two-dimensional frequency-domain acoustic FWI under rugged topography conditions. The exponential attenuation boundary condition suitable for rugged topography is proposed to solve the cutoff boundary problem as well as to consider the requirement of using the same subdivision grid in joint multifrequency inversion. The proposed method introduces the attenuation factor, and by adjusting it, acoustic waves are sufficiently attenuated in the attenuation layer to minimize the cutoff boundary effect. Based on the law of exponential attenuation, expressions for computing the attenuation factor and the thickness of attenuation layers are derived for different frequencies. In multifrequency-domain FWI, the conjugate gradient method is used to solve equations in the Gauss-Newton algorithm and thus minimize the computation cost in calculating the Hessian matrix. In addition, the effect of initial model selection and frequency combination on FWI is analyzed. Examples using numerical simulations and FWI calculations are used to verify the efficiency of the proposed method.

Fibroblast growth factor 21 attenuates hepatic fibrogenesis through TGF-β/smad2/3 and NF-κB signaling pathways

DOE Office of Scientific and Technical Information (OSTI.GOV)

Xu, Pengfei; Zhang, Yingjie; Liu, Yunye

2016-01-01

Fibroblast growth factor 21 (FGF-21) is a secreted protein, which has anti-diabetic and lipocaic effects, but its ability to protect against hepatic fibrosis has not been studied. In this study, we investigated the ability of FGF-21 to attenuate dimethylnitrosamine (DMN)-induced hepatic fibrogenesis in mice and the mechanism of its action. Hepatic fibrosis was induced by injection of DMN, FGF-21 was administered to the mice once daily in association with DMN injection till the end of the experiment. Histopathological examination, tissue 4-hydroxyproline content and expressions of smooth muscle α-actin (α-SMA) and collagen I were measured to assess hepatic fibrosis. Ethanol/PDGF-BB-activated hepaticmore » stellate cells (HSCs) were used to understand the mechanisms of FGF-21 inhibited hepatic fibrogenesis. Results showed that FGF-21 treatment attenuated hepatic fibrogenesis and was associated with a significant decrease in intrahepatic fibrogenesis, 4-hydroxyproline accumulation, α-SMA expression and collagen I deposition. FGF-21 treatment inhibited the activation of HSCs via down-regulating the expression of TGF-β, NF-κB nuclear translocation, phosphorylation levels of smad2/3 and IκBα. Besides, FGF-21 treatment caused activated HSC apoptosis with increasing expression of Caspase-3, and decreased the ratio of Bcl-2 to Bax. In conclusion, FGF-21 attenuates hepatic fibrogenesis and inhibits the activation of HSC warranting the use of FGF-21 as a potential therapeutic agent in the treatment of hepatic fibrosis. - Highlights: • Fibroblast growth factor 21 attenuates hepatic fibrogenesis. • Fibroblast growth factor 21 attenuates hepatic fibrogenesis via TGF-β/smad2/3 signaling pathways. • Fibroblast growth factor 21 attenuates hepatic fibrogenesis via NF-κB signaling pathways.« less

Surge-type glaciers in the Tien Shan (Central Asia)

NASA Astrophysics Data System (ADS)

Mukherjee, Kriti; Bolch, Tobias

2016-04-01

Surge-type glaciers in High Mountain Asia are mostly observed in Karakoram and Pamir. However, few surge-type glaciers also exist in the Tien Shan, but have not comprehensively studied in detail in the recent literature. We identified surge-type glaciers in the Tien Shan either from available literature or by manual interpretation using available satellite images (such as Corona, Hexagon, Landsat, SPOT, IRS) for the period 1960 to 2014. We identified 39 possible surge-type glaciers, showing typical characteristics like looped moraines. Twenty-two of them rapidly advanced during different periods or a surge was clearly described in the literature. For the remaining possible surge-type glaciers either the advance, in terms of time and length, were not mentioned in detail in the literature, or the glaciers have remained either stable or retreated during the entire period of our study. Most of the surge-type glaciers cluster in the Inner Tien Shan (especially in the Ak-Shiirak rage) and the Central Tien Shan, are in size and are facing North, West or North West. Pronounced surge events were observed for North Inylchek and Samoilowitsch glaciers, both of which are located in the Central Tien Shan. Samoilowitsch Glacier retreated by more than 3 km between 1960 (length ~8.9 km) and 1992 (~5.8 km), advanced by almost 3 km until 2006 and slightly retreated thereafter. The most pronounced advance occurred between 2000 and 2002. DEM differencing (based on SRTM3 data and stereo Hexagon and Cartosat-1 data) revealed a significant thickening in the middle reaches (reservoir area) of the glacier between 1973 and 2000 while the surface significantly lowered in the middle and upper parts of the glacier between 2000 and 2006. Hence, the ice mass was transferred to the lower reaches (receiving area) and caused the advance with a maximum thickening of more than 80 m. The ~30 km long North Inylchek Glacier retreated since 1943 and showed a very rapid advance of ~3.5 km especially in the year 1997 with a thickening of the tongue of more than 120 m. Both glaciers showed a surge cycle of about 50 years. The advance was not so pronounced for all other surge-type glaciers. Some of the tributary glaciers behaved differently than the main glaciers in the sense that they continuously advanced during almost the entire period of our study, whereas the main glaciers have remained almost stable or retreated.

Identification of Critical Vulnerable Areas During a Typhoon Haiyan Event in the Metro Manila Area Using Storm Surge Hazard Maps

NASA Astrophysics Data System (ADS)

Briones, J. B. L. T.; Puno, J. V.; Lapidez, J. P. B.; Muldong, T. M. M.; Ramos, M. M.; Caro, C. V.; Ladiero, C.; Bahala, M. A.; Suarez, J. K. B.; Santiago, J. T.

2014-12-01

Sudden rises in sea water over and above astronomical tides due to an approaching storm are known as storm surges. The development of an early warning system for storm surges is imperative, due to the high threat level of these events; Typhoon Haiyan in 08 November 2013 generated storm surges that caused casualties of over 6,000. Under the Department of Science and Technology, the Nationwide Operational Assessment of Hazards (DOST - Project NOAH) was tasked to generate storm surge hazard maps for all the coastal areas in the Philippines. The objective of this paper is to create guidelines on how to utilize the storm surge hazard map as a tool for planning and disaster mitigation. This study uses the case of the hypothetical situation in which a tropical storm with an intensity similar to Typhoon Haiyan hits Metro Manila. This site was chosen for various reasons, among them the economic, political, and cultural importance of Metro Manila as the location of the capital of the Philippines and the coastal bay length of the area. The concentration of residential areas and other establishments were also taken into account. Using the Japan Meteorology Association (JMA) Storm Surge Model, FLO-2D flood modelling software and the application of other GIS technology, the impact of Haiyan-strength typhoon passing through Manila was analysed. We were able to identify the population affected, number of affected critical facilities under each storm surge hazard level, and possible evacuation sites. The results of the study can be used as the basis of policies involving disaster response and mitigation by city authorities. The methods used by the study can be used as a replicable framework for the analysis of other sites in the Philippines.

Numerical investigation of rotating stall in centrifugal compressor with vaned and vaneless diffuser

NASA Astrophysics Data System (ADS)

Halawa, Taher; Alqaradawi, Mohamed; Gadala, Mohamed S.; Shahin, Ibrahim; Badr, Osama

2015-06-01

This study presents a numerical simulation of the stall and surge in a centrifugal compressor and presents a descriptionof the stall development in two different cases. The first case is for a compressor with vaneless diffuser and the second is for a compressor with vaned diffuser of the vane island shape. The main aim of this study is to compare the flow characteristics and behavior for the two compressors near the surge operating condition and provide further understanding of the diffuser role when back flow occurs at surge. Results showed that for a locationnear the diffuser entrance, the amplitude of the static pressure fluctuations for the vaneless diffuser case is higher than that for the vaned diffuser case near surge condition. These pressure fluctuations in the case of the vaneless diffuser appear with a gradual decrease of the mean pressure value as a part of the surge cycle. While for the case of the vaned diffuser, the pressure drop during surge occurs faster than the case of the vaneless diffuser. Also, results indicated that during surge in the case of vaneless diffuser, there is a region with low velocity and back flow that appears as a layer connecting all impeller passages near shroud surface and this layer develops in size with time. On the other hand, for the case of vaned diffuser during surge, the low velocity regions appear in random locations in some passages and these regions expand with time towards the shroud surface. Results showed that during stall, the impeller passages are exposed to identical impact from stall cells in the case of vaneless diffuser while the stall effect varies from passage to another in the case of the vaned diffuser.

Tsivat Basin conduit system persists through two surges, Bering Piedmont Glacier, Alaska

USGS Publications Warehouse

Fleisher, P.J.; Cadwell, D.H.; Muller, E.H.

1998-01-01

The 1993-1995 surge of Bering Glacier, Alaska, occurred in two distinct phases. Phase 1 of the surge began on the eastern sector in July, 1993 and ended in July, 1994 after a powerful outburst of subglacial meltwater into Tsivat Lake basin on the north side of Weeping Peat Island. Within days, jokulhlaup discharge built a 1.5 km2 delta of ice blocks (25-30 m) buried in outwash. By late October 1994, discharge temporarily shifted to a vent on Weeping Peat Island, where a second smaller outburst dissected the island and built two new sandar. During phase 2, which began in spring 1995 and ended within five months, continuous discharge issued from several vents along the ice front on Weeping Peat Island before returining to the Tsivat Basin. Surge related changes include a five- to six-fold increase in meltwater turbidity; the redirection of supercooled water in two ice-contact lakes; and an increase in the rate of glaciolacustrine sedimentation. US Geological Survey aerial photos by Austin Post show large ice blocks in braided channels indicating excessive subglacial discharge in a similar position adjacent to Weeping Peat Island during the 1966-1967 surge. During the subsequent three decades of retreat, the location of ice-marginal, subglacial discharge vents remained aligned on a linear trend that describes the position of a persistent subglacial conduit system. The presence of a major conduit system, possibly stabilized by subglacial bedrock topography, is suggested by: 1) high-level subglacial meltwater venting along the northern side of Weeping Peat Island during the 1966-1967 surge, 2) persistent low-level discharge between surges, and 3) the recurrence of localizing meltwater outbursts associated with both phases of the 1993-1005 surge.

A modeling study of coastal inundation induced by storm surge, sea-level rise, and subsidence in the Gulf of Mexico

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yang, Zhaoqing; Wang, Taiping; Leung, Lai-Yung R.

The northern coasts of the Gulf of Mexico are highly vulnerable to the direct threats of climate change, such as hurricane-induced storm surge, and such risks can be potentially exacerbated by land subsidence and global sea level rise. This paper presents an application of a coastal storm surge model to study the coastal inundation process induced by tide and storm surge, and its response to the effects of land subsidence and sea level rise in the northern Gulf coast. An unstructured-grid Finite Volume Coastal Ocean Model was used to simulate tides and hurricane-induced storm surges in the Gulf of Mexico.more » Simulated distributions of co-amplitude and co-phase of semi-diurnal and diurnal tides are in good agreement with previous modeling studies. The storm surges induced by four historical hurricanes (Rita, Katrina, Ivan and Dolly) were simulated and compared to observed water levels at National Oceanic and Atmospheric Administration tide stations. Effects of coastal subsidence and future global sea level rise on coastal inundation in the Louisiana coast were evaluated using a parameter “change of inundation depth” through sensitivity simulations that were based on a projected future subsidence scenario and 1-m global sea level rise by the end of the century. Model results suggested that hurricane-induced storm surge height and coastal inundation could be exacerbated by future global sea level rise and subsidence, and that responses of storm surge and coastal inundation to the effects of sea level rise and subsidence are highly nonlinear and vary on temporal and spatial scales.« less

Runoff-generated debris flows: observations and modeling of surge initiation, magnitude, and frequency

USGS Publications Warehouse

Kean, Jason W.; McCoy, Scott W.; Tucker, Gregory E.; Staley, Dennis M.; Coe, Jeffrey A.

2013-01-01

Runoff during intense rainstorms plays a major role in generating debris flows in many alpine areas and burned steeplands. Yet compared to debris flow initiation from shallow landslides, the mechanics by which runoff generates a debris flow are less understood. To better understand debris flow initiation by surface water runoff, we monitored flow stage and rainfall associated with debris flows in the headwaters of two small catchments: a bedrock-dominated alpine basin in central Colorado (0.06 km2) and a recently burned area in southern California (0.01 km2). We also obtained video footage of debris flow initiation and flow dynamics from three cameras at the Colorado site. Stage observations at both sites display distinct patterns in debris flow surge characteristics relative to rainfall intensity (I). We observe small, quasiperiodic surges at low I; large, quasiperiodic surges at intermediate I; and a single large surge followed by small-amplitude fluctuations about a more steady high flow at high I. Video observations of surge formation lead us to the hypothesis that these flow patterns are controlled by upstream variations in channel slope, in which low-gradient sections act as “sediment capacitors,” temporarily storing incoming bed load transported by water flow and periodically releasing the accumulated sediment as a debris flow surge. To explore this hypothesis, we develop a simple one-dimensional morphodynamic model of a sediment capacitor that consists of a system of coupled equations for water flow, bed load transport, slope stability, and mass flow. This model reproduces the essential patterns in surge magnitude and frequency with rainfall intensity observed at the two field sites and provides a new framework for predicting the runoff threshold for debris flow initiation in a burned or alpine setting.

Compound simulation of fluvial floods and storm surges in a global coupled river-coast flood model: Model development and its application to 2007 Cyclone Sidr in Bangladesh

NASA Astrophysics Data System (ADS)

Ikeuchi, Hiroaki; Hirabayashi, Yukiko; Yamazaki, Dai; Muis, Sanne; Ward, Philip J.; Winsemius, Hessel C.; Verlaan, Martin; Kanae, Shinjiro

2017-08-01

Water-related disasters, such as fluvial floods and cyclonic storm surges, are a major concern in the world's mega-delta regions. Furthermore, the simultaneous occurrence of extreme discharges from rivers and storm surges could exacerbate flood risk, compared to when they occur separately. Hence, it is of great importance to assess the compound risks of fluvial and coastal floods at a large scale, including mega-deltas. However, most studies on compound fluvial and coastal flooding have been limited to relatively small scales, and global-scale or large-scale studies have not yet addressed both of them. The objectives of this study are twofold: to develop a global coupled river-coast flood model; and to conduct a simulation of compound fluvial flooding and storm surges in Asian mega-delta regions. A state-of-the-art global river routing model was modified to represent the influence of dynamic sea surface levels on river discharges and water levels. We conducted the experiments by coupling a river model with a global tide and surge reanalysis data set. Results show that water levels in deltas and estuaries are greatly affected by the interaction between river discharge, ocean tides and storm surges. The effects of storm surges on fluvial flooding are further examined from a regional perspective, focusing on the case of Cyclone Sidr in the Ganges-Brahmaputra-Meghna Delta in 2007. Modeled results demonstrate that a >3 m storm surge propagated more than 200 km inland along rivers. We show that the performance of global river routing models can be improved by including sea level dynamics.

A simplified real time method to forecast semi-enclosed basins storm surge

NASA Astrophysics Data System (ADS)

Pasquali, D.; Di Risio, M.; De Girolamo, P.

2015-11-01

Semi-enclosed basins are often prone to storm surge events. Indeed, their meteorological exposition, the presence of large continental shelf and their shape can lead to strong sea level set-up. A real time system aimed at forecasting storm surge may be of great help to protect human activities (i.e. to forecast flooding due to storm surge events), to manage ports and to safeguard coasts safety. This paper aims at illustrating a simple method able to forecast storm surge events in semi-enclosed basins in real time. The method is based on a mixed approach in which the results obtained by means of a simplified physics based model with low computational costs are corrected by means of statistical techniques. The proposed method is applied to a point of interest located in the Northern part of the Adriatic Sea. The comparison of forecasted levels against observed values shows the satisfactory reliability of the forecasts.

Hurricane modification and adaptation in Miami-Dade County, Florida.

PubMed

Klima, Kelly; Lin, Ning; Emanuel, Kerry; Morgan, M Granger; Grossmann, Iris

2012-01-17

We investigate tropical cyclone wind and storm surge damage reduction for five areas along the Miami-Dade County coastline either by hardening buildings or by the hypothetical application of wind-wave pumps to modify storms. We calculate surge height and wind speed as functions of return period and sea surface temperature reduction by wind-wave pumps. We then estimate costs and economic losses with the FEMA HAZUS-MH MR3 damage model and census data on property at risk. All areas experience more surge damages for short return periods, and more wind damages for long periods. The return period at which the dominating hazard component switches depends on location. We also calculate the seasonal expected fraction of control damage for different scenarios to reduce damages. Surge damages are best reduced through a surge barrier. Wind damages are best reduced by a portfolio of techniques that, assuming they work and are correctly deployed, include wind-wave pumps.

Algorithm for Controlling a Centrifugal Compressor

NASA Technical Reports Server (NTRS)

Benedict, Scott M.

2004-01-01

An algorithm has been developed for controlling a centrifugal compressor that serves as the prime mover in a heatpump system. Experimental studies have shown that the operating conditions for maximum compressor efficiency are close to the boundary beyond which surge occurs. Compressor surge is a destructive condition in which there are instantaneous reversals of flow associated with a high outlet-to-inlet pressure differential. For a given cooling load, the algorithm sets the compressor speed at the lowest possible value while adjusting the inlet guide vane angle and diffuser vane angle to maximize efficiency, subject to an overriding requirement to prevent surge. The onset of surge is detected via the onset of oscillations of the electric current supplied to the compressor motor, associated with surge-induced oscillations of the torque exerted by and on the compressor rotor. The algorithm can be implemented in any of several computer languages.

Evaluation of Ferrite Chip Beads as Surge Current Limiters in Circuits with Tantalum Capacitors

NASA Technical Reports Server (NTRS)

Teverovsky, Alexander

2014-01-01

Limiting resistors are currently required to be connected in series with tantalum capacitors to reduce the risk of surge current failures. However, application of limiting resistors decreases substantially the efficiency of the power supply systems. An ideal surge current limiting device should have a negligible resistance for DC currents and high resistance at frequencies corresponding to transients in tantalum capacitors. This work evaluates the possibility of using chip ferrite beads (FB) as such devices. Twelve types of small size FBs from three manufacturers were used to evaluate their robustness under soldering stresses and at high surge current spikes associated with transients in tantalum capacitors. Results show that FBs are capable to withstand current pulses that are substantially greater than the specified current limits. However, due to a sharp decrease of impedance with current, FBs do not reduce surge currents to the required level that can be achieved with regular resistors.

[The role of patient flow and surge capacity for in-hospital response in mass casualty events].

PubMed

Sefrin, Peter; Kuhnigk, Herbert

2008-03-01

Mass casualty events make demands on emergency services and disaster control. However, optimized in- hospital response defines the quality of definitive care. Therefore, German federal law governs the role of hospitals in mass casualty incidents. In hospital casualty surge is depending on resources that have to be expanded with a practicable alarm plan. Thus, in-hospital mass casualty management planning is recommended to be organized by specialized persons. To minimise inhospital patient overflow casualty surge principles have to be implemented in both, pre-hospital and in-hospital disaster planning. World soccer championship 2006 facilitated the initiation of surge and damage control principles in in-hospital disaster planning strategies for German hospitals. The presented concept of strict control of in-hospital patient flow using surge principles minimises the risk of in-hospital breakdown and increases definitive hospital treatment capacity in mass casualty incidents.

Statistical Analysis of Instantaneous Frequency Scaling Factor as Derived From Optical Disdrometer Measurements At KQ Bands

NASA Technical Reports Server (NTRS)

Zemba, Michael; Nessel, James; Houts, Jacquelynne; Luini, Lorenzo; Riva, Carlo

2016-01-01

The rain rate data and statistics of a location are often used in conjunction with models to predict rain attenuation. However, the true attenuation is a function not only of rain rate, but also of the drop size distribution (DSD). Generally, models utilize an average drop size distribution (Laws and Parsons or Marshall and Palmer. However, individual rain events may deviate from these models significantly if their DSD is not well approximated by the average. Therefore, characterizing the relationship between the DSD and attenuation is valuable in improving modeled predictions of rain attenuation statistics. The DSD may also be used to derive the instantaneous frequency scaling factor and thus validate frequency scaling models. Since June of 2014, NASA Glenn Research Center (GRC) and the Politecnico di Milano (POLIMI) have jointly conducted a propagation study in Milan, Italy utilizing the 20 and 40 GHz beacon signals of the Alphasat TDP#5 Aldo Paraboni payload. The Ka- and Q-band beacon receivers provide a direct measurement of the signal attenuation while concurrent weather instrumentation provides measurements of the atmospheric conditions at the receiver. Among these instruments is a Thies Clima Laser Precipitation Monitor (optical disdrometer) which yields droplet size distributions (DSD); this DSD information can be used to derive a scaling factor that scales the measured 20 GHz data to expected 40 GHz attenuation. Given the capability to both predict and directly observe 40 GHz attenuation, this site is uniquely situated to assess and characterize such predictions. Previous work using this data has examined the relationship between the measured drop-size distribution and the measured attenuation of the link]. The focus of this paper now turns to a deeper analysis of the scaling factor, including the prediction error as a function of attenuation level, correlation between the scaling factor and the rain rate, and the temporal variability of the drop size distribution both within a given rain event and across different varieties of rain events. Index Terms-drop size distribution, frequency scaling, propagation losses, radiowave propagation.

Statistical Analysis of Instantaneous Frequency Scaling Factor as Derived From Optical Disdrometer Measurements At KQ Bands

NASA Technical Reports Server (NTRS)

Zemba, Michael; Nessel, James; Houts, Jacquelynne; Luini, Lorenzo; Riva, Carlo

2016-01-01

The rain rate data and statistics of a location are often used in conjunction with models to predict rain attenuation. However, the true attenuation is a function not only of rain rate, but also of the drop size distribution (DSD). Generally, models utilize an average drop size distribution (Laws and Parsons or Marshall and Palmer [1]). However, individual rain events may deviate from these models significantly if their DSD is not well approximated by the average. Therefore, characterizing the relationship between the DSD and attenuation is valuable in improving modeled predictions of rain attenuation statistics. The DSD may also be used to derive the instantaneous frequency scaling factor and thus validate frequency scaling models. Since June of 2014, NASA Glenn Research Center (GRC) and the Politecnico di Milano (POLIMI) have jointly conducted a propagation study in Milan, Italy utilizing the 20 and 40 GHz beacon signals of the Alphasat TDP#5 Aldo Paraboni payload. The Ka- and Q-band beacon receivers provide a direct measurement of the signal attenuation while concurrent weather instrumentation provides measurements of the atmospheric conditions at the receiver. Among these instruments is a Thies Clima Laser Precipitation Monitor (optical disdrometer) which yields droplet size distributions (DSD); this DSD information can be used to derive a scaling factor that scales the measured 20 GHz data to expected 40 GHz attenuation. Given the capability to both predict and directly observe 40 GHz attenuation, this site is uniquely situated to assess and characterize such predictions. Previous work using this data has examined the relationship between the measured drop-size distribution and the measured attenuation of the link [2]. The focus of this paper now turns to a deeper analysis of the scaling factor, including the prediction error as a function of attenuation level, correlation between the scaling factor and the rain rate, and the temporal variability of the drop size distribution both within a given rain event and across different varieties of rain events. Index Terms-drop size distribution, frequency scaling, propagation losses, radiowave propagation.

Community College Enrollment Surge: An Analysis of Estimated Fall 2009 Headcount Enrollments at Community Colleges. Policy Brief 2009-01PBL

ERIC Educational Resources Information Center

Mullin, Christopher M.; Phillippe, Kent

2009-01-01

In an attempt to better understand how community colleges responded to the economic maelstrom, the American Association of Community Colleges (AACC) surveyed its member institutions to examine changes in enrollment, local factors contributing to enrollment shifts, and the lessons learned from their experiences. The authors found the following: (1)…

Global mortality from storm surges is decreasing

NASA Astrophysics Data System (ADS)

Bouwer, Laurens M.; Jonkman, Sebastiaan N.

2018-01-01

Changes in society’s vulnerability to natural hazards are important to understand, as they determine current and future risks, and the need to improve protection. Very large impacts including high numbers of fatalities occur due to single storm surge flood events. Here, we report on impacts of global coastal storm surge events since the year 1900, based on a compilation of events and data on loss of life. We find that over the past, more than eight thousand people are killed and 1.5 million people are affected annually by storm surges. The occurrence of very substantial loss of life (>10 000 persons) from single events has however decreased over time. Moreover, there is a consistent decrease in event mortality, measured by the fraction of exposed people that are killed, for all global regions, except South East Asia. Average mortality for storm surges is slightly higher than for river floods, but lower than for flash floods. We also find that for the same coastal surge water level, mortality has decreased over time. This indicates that risk reduction efforts have been successful, but need to be continued with projected climate change, increased rates of sea-level rise and urbanisation in coastal zones.

Surrogate modeling of joint flood risk across coastal watersheds

NASA Astrophysics Data System (ADS)

Bass, Benjamin; Bedient, Philip

2018-03-01

This study discusses the development and performance of a rapid prediction system capable of representing the joint rainfall-runoff and storm surge flood response of tropical cyclones (TCs) for probabilistic risk analysis. Due to the computational demand required for accurately representing storm surge with the high-fidelity ADvanced CIRCulation (ADCIRC) hydrodynamic model and its coupling with additional numerical models to represent rainfall-runoff, a surrogate or statistical model was trained to represent the relationship between hurricane wind- and pressure-field characteristics and their peak joint flood response typically determined from physics based numerical models. This builds upon past studies that have only evaluated surrogate models for predicting peak surge, and provides the first system capable of probabilistically representing joint flood levels from TCs. The utility of this joint flood prediction system is then demonstrated by improving upon probabilistic TC flood risk products, which currently account for storm surge but do not take into account TC associated rainfall-runoff. Results demonstrate the source apportionment of rainfall-runoff versus storm surge and highlight that slight increases in flood risk levels may occur due to the interaction between rainfall-runoff and storm surge as compared to the Federal Emergency Management Association's (FEMAs) current practices.

Probabilistic storm surge inundation maps for Metro Manila based on Philippine public storm warning signals

NASA Astrophysics Data System (ADS)

Tablazon, J.; Caro, C. V.; Lagmay, A. M. F.; Briones, J. B. L.; Dasallas, L.; Lapidez, J. P.; Santiago, J.; Suarez, J. K.; Ladiero, C.; Gonzalo, L. A.; Mungcal, M. T. F.; Malano, V.

2015-03-01

A storm surge is the sudden rise of sea water over the astronomical tides, generated by an approaching storm. This event poses a major threat to the Philippine coastal areas, as manifested by Typhoon Haiyan on 8 November 2013. This hydro-meteorological hazard is one of the main reasons for the high number of casualties due to the typhoon, with 6300 deaths. It became evident that the need to develop a storm surge inundation map is of utmost importance. To develop these maps, the Nationwide Operational Assessment of Hazards under the Department of Science and Technology (DOST-Project NOAH) simulated historical tropical cyclones that entered the Philippine Area of Responsibility. The Japan Meteorological Agency storm surge model was used to simulate storm surge heights. The frequency distribution of the maximum storm surge heights was calculated using simulation results of tropical cyclones under a specific public storm warning signal (PSWS) that passed through a particular coastal area. This determines the storm surge height corresponding to a given probability of occurrence. The storm surge heights from the model were added to the maximum astronomical tide data from WXTide software. The team then created maps of inundation for a specific PSWS using the probability of exceedance derived from the frequency distribution. Buildings and other structures were assigned a probability of exceedance depending on their occupancy category, i.e., 1% probability of exceedance for critical facilities, 10% probability of exceedance for special occupancy structures, and 25% for standard occupancy and miscellaneous structures. The maps produced show the storm-surge-vulnerable areas in Metro Manila, illustrated by the flood depth of up to 4 m and extent of up to 6.5 km from the coastline. This information can help local government units in developing early warning systems, disaster preparedness and mitigation plans, vulnerability assessments, risk-sensitive land use plans, shoreline defense efforts, and coastal protection measures. These maps can also determine the best areas to build critical structures, or at least determine the level of protection of these structures should they be built in hazard areas. Moreover, these will support the local government units' mandate to raise public awareness, disseminate information about storm surge hazards, and implement appropriate countermeasures for a given PSWS.

Centrifugal Compressor Surge Margin Improved With Diffuser Hub Surface Air Injection

NASA Technical Reports Server (NTRS)

Skoch, Gary J.

2002-01-01

Aerodynamic stability is an important parameter in the design of compressors for aircraft gas turbine engines. Compression system instabilities can cause compressor surge, which may lead to the loss of an aircraft. As a result, engine designers include a margin of safety between the operating line of the engine and the stability limit line of the compressor. The margin of safety is typically referred to as "surge margin." Achieving the highest possible level of surge margin while meeting design point performance objectives is the goal of the compressor designer. However, performance goals often must be compromised in order to achieve adequate levels of surge margin. Techniques to improve surge margin will permit more aggressive compressor designs. Centrifugal compressor surge margin improvement was demonstrated at the NASA Glenn Research Center by injecting air into the vaned diffuser of a 4:1-pressure-ratio centrifugal compressor. Tests were performed using injector nozzles located on the diffuser hub surface of a vane-island diffuser in the vaneless region between the impeller trailing edge and the diffuser-vane leading edge. The nozzle flow path and discharge shape were designed to produce an air stream that remained tangent to the hub surface as it traveled into the diffuser passage. Injector nozzles were located near the leading edge of 23 of the 24 diffuser vanes. One passage did not contain an injector so that instrumentation located in that passage would be preserved. Several orientations of the injected stream relative to the diffuser vane leading edge were tested over a range of injected flow rates. Only steady flow (nonpulsed) air injection was tested. At 100 percent of the design speed, a 15-percent improvement in the baseline surge margin was achieved with a nozzle orientation that produced a jet that was bisected by the diffuser vane leading edge. Other orientations also improved the baseline surge margin. Tests were conducted at speeds below the design speed, and similar results were obtained. In most cases, the greatest improvement in surge margin occurred at fairly low levels of injected flow rate. Externally supplied injection air was used in these experiments. However, the injected flow rates that provided the greatest benefit could be produced using injection air that is recirculating between the diffuser discharge and nozzles located in the diffuser vaneless region. Future experiments will evaluate the effectiveness of recirculating air injection.

Ability of regional hospitals to meet projected avian flu pandemic surge capacity requirements.

PubMed

Ten Eyck, Raymond P

2008-01-01

Hospital surge capacity is a crucial part of community disaster preparedness planning, which focuses on the requirements for additional beds, equipment, personnel, and special capabilities. The scope and urgency of these requirements must be balanced with a practical approach addressing cost and space concerns. Renewed concerns for infectious disease threats, particularly from a potential avian flu pandemic perspective, have emphasized the need to be prepared for a prolonged surge that could last six to eight weeks. The surge capacity that realistically would be generated by the cumulative Greater Dayton Area Hospital Association (GDAHA) plan is sufficient to meet the demands of an avian influenza pandemic as predicted by the [US] Centers for Disease Control and Prevention (CDC) models. Using a standardized data form, surge response plans for each hospital in the GDAHA were assessed. The cumulative results were compared to the demand projected for an avian influenza pandemic using the CDC's FluAid and FluSurge models. The cumulative GDAHA capacity is sufficient to meet the projected demand for bed space, intensive care unit beds, ventilators, morgue space, and initial personal protective equipment (PPE) use. There is a shortage of negative pressure rooms, some basic equipment, and neuraminidase inhibitors. Many facilities lack a complete set of written surge policies, including screening plans to segregate contaminated patients and staff prior to entering the hospital. Few hospitals have agreements with nursing homes or home healthcare agencies to provide care for patients discharged in order to clear surge beds. If some of the assumptions in the CDC's models are changed to match the morbidity and mortality rates reported from the 1918 pandemic, the surge capacity of GDAHA facilities would not meet the projected demand. The GDAHA hospitals should test their regional distributors' ability to resupply PPE for multiple facilities simultaneously. Facilities should retrofit current air exchange systems to increase the number of potential negative pressure rooms and include such designs in all future construction. Neuraminidase inhibitor supplies should be increased to provide treatment for healthcare workers exposed in the course of their duties. Each hospital should have a complete set of policies to address the special considerations for a prolonged surge. Additional capacity is required to meet the predicted demands of a threat similar to the 1918 pandemic.

Physical and Economic Impacts of Sea-Level Rise and Low Probability Flooding Events on Coastal Communities

PubMed Central

Prime, Thomas; Brown, Jennifer M.; Plater, Andrew J.

2015-01-01

Conventionally flood mapping typically includes only a static water level (e.g. peak of a storm tide) in coastal flood inundation events. Additional factors become increasingly important when increased water-level thresholds are met during the combination of a storm tide and increased mean sea level. This research incorporates factors such as wave overtopping and river flow in a range of flood inundation scenarios of future sea-level projections for a UK case study of Fleetwood, northwest England. With increasing mean sea level it is shown that wave overtopping and river forcing have an important bearing on the cost of coastal flood events. The method presented converts inundation maps into monetary cost. This research demonstrates that under scenarios of joint extreme surge-wave-river events the cost of flooding can be increased by up to a factor of 8 compared with an increase in extent of up to a factor of 3 relative to “surge alone” event. This is due to different areas being exposed to different flood hazards and areas with common hazard where flood waters combine non-linearly. This shows that relying simply on flood extent and volume can under-predict the actual economic impact felt by a coastal community. Additionally, the scenario inundation depths have been presented as “brick course” maps, which represent a new way of interpreting flood maps. This is primarily aimed at stakeholders to increase levels of engagement within the coastal community. PMID:25710497

Validation of a Framework for Measuring Hospital Disaster Resilience Using Factor Analysis

PubMed Central

Zhong, Shuang; Clark, Michele; Hou, Xiang-Yu; Zang, Yuli; FitzGerald, Gerard

2014-01-01

Hospital disaster resilience can be defined as “the ability of hospitals to resist, absorb, and respond to the shock of disasters while maintaining and surging essential health services, and then to recover to its original state or adapt to a new one.” This article aims to provide a framework which can be used to comprehensively measure hospital disaster resilience. An evaluation framework for assessing hospital resilience was initially proposed through a systematic literature review and Modified-Delphi consultation. Eight key domains were identified: hospital safety, command, communication and cooperation system, disaster plan, resource stockpile, staff capability, disaster training and drills, emergency services and surge capability, and recovery and adaptation. The data for this study were collected from 41 tertiary hospitals in Shandong Province in China, using a specially designed questionnaire. Factor analysis was conducted to determine the underpinning structure of the framework. It identified a four-factor structure of hospital resilience, namely, emergency medical response capability (F1), disaster management mechanisms (F2), hospital infrastructural safety (F3), and disaster resources (F4). These factors displayed good internal consistency. The overall level of hospital disaster resilience (F) was calculated using the scoring model: F = 0.615F1 + 0.202F2 + 0.103F3 + 0.080F4. This validated framework provides a new way to operationalise the concept of hospital resilience, and it is also a foundation for the further development of the measurement instrument in future studies. PMID:24945190

Physical and economic impacts of sea-level rise and low probability flooding events on coastal communities.

PubMed

Prime, Thomas; Brown, Jennifer M; Plater, Andrew J

2015-01-01

Conventionally flood mapping typically includes only a static water level (e.g. peak of a storm tide) in coastal flood inundation events. Additional factors become increasingly important when increased water-level thresholds are met during the combination of a storm tide and increased mean sea level. This research incorporates factors such as wave overtopping and river flow in a range of flood inundation scenarios of future sea-level projections for a UK case study of Fleetwood, northwest England. With increasing mean sea level it is shown that wave overtopping and river forcing have an important bearing on the cost of coastal flood events. The method presented converts inundation maps into monetary cost. This research demonstrates that under scenarios of joint extreme surge-wave-river events the cost of flooding can be increased by up to a factor of 8 compared with an increase in extent of up to a factor of 3 relative to "surge alone" event. This is due to different areas being exposed to different flood hazards and areas with common hazard where flood waters combine non-linearly. This shows that relying simply on flood extent and volume can under-predict the actual economic impact felt by a coastal community. Additionally, the scenario inundation depths have been presented as "brick course" maps, which represent a new way of interpreting flood maps. This is primarily aimed at stakeholders to increase levels of engagement within the coastal community.

Relationship between diverse patient body size- and image acquisition-related factors, and quantitative and qualitative image quality in coronary computed tomography angiography: a multicenter observational study.

PubMed

Utsunomiya, Daisuke; Tanaka, Ryoichi; Yoshioka, Kunihiro; Awai, Kazuo; Mochizuki, Teruhito; Matsunaga, Naofumi; Ichikawa, Tomoaki; Kanematsu, Masayuki; Kim, Tonsok; Yamashita, Yasuyuki

2016-08-01

We investigated the effects of patient- and image acquisition-related factors on the image quality in coronary CT angiography (CCTA). We enrolled 1197 patients (728 men; 65 ± 12 years). All underwent CCTA under the routine scan protocol in 23 participating hospitals. The subjective image quality (3-point Likert scale: excellent, good, and poor) and the attenuation of the left and right coronary artery (LCA, RCA) were recorded; the effects of patient and image acquisition-related factors on vascular attenuation were then compared. The mean LCA attenuation was 515.2 ± 65.8 (excellent), 401.4 ± 63.4 (good), and 319.5 ± 47.6 HU (poor). The corresponding RCA attenuation was 496.6 ± 67.6, 390.5 ± 58.5, and 308.5 ± 50.7 HU, respectively. Univariate analysis revealed significant associations between sufficient coronary attenuation (> 400 HU) and the age, gender, body surface area (BSA), number of detectors, contrast synchronization, scan mode, and the fractional contrast dose. Multivariate analysis revealed that the bolus tracking method, prospective electrocardiogram gating, and fractional contrast dose were significantly associated with sufficient coronary enhancement. BSA and fractional contrast dose are the most important patient- and image acquisition-related factors for sufficient coronary attenuation in CCTA.

Biodegradation of Petroleum Hydrocarbon in the Vadose Zone

EPA Science Inventory

There are two major impediments to a better understanding of the influence of biodegradation on the risk of intrusion of petroleum vapors. We describe the contribution of biodegradation as an attenuation factor between the source and the receptor. The use of attenuation factors...

Factors Affecting Inlet-Engine Compatibility During Aircraft Departures at High Angle of Attack for an F/A -18A Aircraft

NASA Technical Reports Server (NTRS)

Steenken, W. G.; Williams, J. G.; Yuhas, A. J.; Walsh, K. R.

1999-01-01

The F404-GE-400 engine powered F/A- 18A High Alpha Research Vehicle (HARV) was used to examine the quality of inlet airflow during departed flight maneuvers, that is, during flight outside the normal maneuvering envelope where control surfaces have little or no effectiveness. A series of six nose-left and six nose-right departures were initiated at Mach numbers between 0.3 and 0.4 at an altitude of 35 kft. The yaw rates at departure recovery were in the range of 40 to 90 degrees per second. Engine surges were encountered during three of the nose-left and one of the nose-right departures. Time-variant inlet-total-pressure distortion levels at the engine face were determined to not significantly exceed those measured at maximum angle-of-attack and - sideslip maneuvers during controlled flight. Surges as a result of inlet distortion levels were anticipated to initiate in the fan. Analysis revealed that the surges initiated in the compressor and were the result of a combination of high levels of inlet distortion and rapid changes in aircraft motion. These rapid changes in aircraft motion are indicative of a combination of engine mount and gyroscopic loads being applied to the engine structure that impact the aerodynamic stability of the compressor through changes in the rotor-to-case clearances.

Comparison of Coastal Inundation in the Outer Banks during Three Recent Hurricanes

NASA Astrophysics Data System (ADS)

Liu, T.; Sheng, Y.

2012-12-01

Coastal inundation in the Outer Banks and Chesapeake Bay during several recent hurricanes - Isabel, Earl and Irene, in 2005, 2010 and 2011, respectively, have been successfully simulated using the storm surge modeling system, CH3D-SSMS, which includes coupled coastal and basin-scale storm surge and wave models. Hurricane Isabel, which made landfall at the Outer Banks area in 2005, generated high waves up to 20 m offshore and 2.5 m inside the Chesapeake Bay which significantly affected the peak surge, with wave induced set-up contributing up to about 20% of the peak surge. During Isabel, the observed wave height at Duck station (1 km offshore) reached over 6 meters at landfall time, while Earl and Irene generated relatively moderate waves, with peak wave height around 4 meters at that station but a much lower wave height before landfall. Simulations show that during Earl and Irene, wave induced set-up did not contribute as much as that during Isabel. At Duck Pier, wave effects accounted for ~36 cm or 20% of the peak surge of 1.71 m during Isabel, while waves contributed ~10 cm (10%) toward the peak surge of 1 m during Irene and even less during Earl. The maximum surge during Irene was largely caused by the strong wind, as confirmed by the model using H* wind. Inundation maps have been generated and compared based on the simulations of Isabel, Earl and Irene.

Modeling and simulation of storm surge on Staten Island to understand inundation mitigation strategies

USGS Publications Warehouse

Kress, Michael E.; Benimoff, Alan I.; Fritz, William J.; Thatcher, Cindy A.; Blanton, Brian O.; Dzedzits, Eugene

2016-01-01

Hurricane Sandy made landfall on October 29, 2012, near Brigantine, New Jersey, and had a transformative impact on Staten Island and the New York Metropolitan area. Of the 43 New York City fatalities, 23 occurred on Staten Island. The borough, with a population of approximately 500,000, experienced some of the most devastating impacts of the storm. Since Hurricane Sandy, protective dunes have been constructed on the southeast shore of Staten Island. ADCIRC+SWAN model simulations run on The City University of New York's Cray XE6M, housed at the College of Staten Island, using updated topographic data show that the coast of Staten Island is still susceptible to tidal surge similar to those generated by Hurricane Sandy. Sandy hindcast simulations of storm surges focusing on Staten Island are in good agreement with observed storm tide measurements. Model results calculated from fine-scaled and coarse-scaled computational grids demonstrate that finer grids better resolve small differences in the topography of critical hydraulic control structures, which affect storm surge inundation levels. The storm surge simulations, based on post-storm topography obtained from high-resolution lidar, provide much-needed information to understand Staten Island's changing vulnerability to storm surge inundation. The results of fine-scale storm surge simulations can be used to inform efforts to improve resiliency to future storms. For example, protective barriers contain planned gaps in the dunes to provide for beach access that may inadvertently increase the vulnerability of the area.

Linkage of Rainfall-Runoff and Hurricane Storm Surge in Galveston Bay

NASA Astrophysics Data System (ADS)

Deitz, R.; Christian, J.; Wright, G.; Fang, N.; Bedient, P.

2012-12-01

In conjunction with the SSPEED Center, large rainfall events in the upper Gulf of Mexico are being studied in an effort to help design a surge gate to protect the Houston Ship Channel during hurricane events. The ship channel is the world's second largest petrochemical complex and the Coast Guard estimates that a one-month closure would have a $60 billion dollar impact on the national economy. In this effort, statistical design storms, such as the 24-hour PMP, as well as historical storms, like Hurricane Ike, Hurricane Katrina, and Hurricane Rita, are being simulated in a hydrologic/hydraulic model using radar and rain gauge data. VfloTM, a distributed hydrologic model, is being used to quantify the effect that storm size, intensity, and location has on timing and peak flows in the in the upper drainage area. These hydrographs were input to a hydraulic model with various storm surges from Galveston Bay. Results indicate that there is a double peak phenomenon with flows from the west draining days earlier than flows from the north. With storm surge typically lasting 36-48 hours, this indicates the flows from the west are interacting with the storm surge, whereas flows from the north would arrive once the storm surge is receding. Gate operations were optimized in the model to account for the relative timing of upland runoff and hurricane surge, and to quantify the capability of the gate structure to protect the Ship Channel industry.

The Propagation of a Surge Front on Bering Glacier, Alaska, 2001-2011

NASA Technical Reports Server (NTRS)

Turrin, James; Forster, Richard R.; Larsen, Chris; Sauber, Jeanne

2013-01-01

Bering Glacier, Alaska, USA, has a 20 year surge cycle, with its most recent surge reaching the terminus in 2011. To study this most recent activity a time series of ice velocity maps was produced by applying optical feature-tracking methods to Landsat-7 ETM+ imagery spanning 2001-11. The velocity maps show a yearly increase in ice surface velocity associated with the down-glacier movement of a surge front. In 2008/09 the maximum ice surface velocity was 1.5 plus or minus 0.017 kilometers per a in the mid-ablation zone, which decreased to 1.2 plus or minus 0.015 kilometers per a in 2009/10 in the lower ablation zone, and then increased to nearly 4.4 plus or minus 0.03 kilometers per a in summer 2011 when the surge front reached the glacier terminus. The surge front propagated down-glacier as a kinematic wave at an average rate of 4.4 plus or minus 2.0 kilometers per a between September 2002 and April 2009, then accelerated to 13.9 plus or minus 2.0 kilometers per a as it entered the piedmont lobe between April 2009 and September 2010. Thewave seems to have initiated near the confluence of Bering Glacier and Bagley Ice Valley as early as 2001, and the surge was triggered in 2008 further down-glacier in the mid-ablation zone after the wave passed an ice reservoir area.

On using scatterometer and altimeter data to improve storm surge forecasting in the Adriatic Sea

NASA Astrophysics Data System (ADS)

Bajo, Marco; Umgiesser, Georg; De Biasio, Francesco; Vignudelli, Stefano; Zecchetto, Stefano

2017-04-01

Satellite data are seldom used in storm surge forecasting. Among the most important issues related to the storm surge forecasting are the quality of the model wind forcing and the initial condition of the sea surface elevation. In this work, focused on storm surge forecasting in the Adriatic Sea, satellite scatterometer wind data are used to correct the wind speed and direction biases of the ECMWF global atmospheric model by tuning the spatial fields, as an alternative to data assimilation. The capability of such an unbiased wind is tested against that of a high resolution wind, produced by a regional non-hydrostatic model. On the other hand, altimeter Total Water Level Envelope (TWLE) data, which provide the sea level elevation, are used to improve the accuracy of the initial state of the model simulations. This is done by assimilating into a storm surge model the TWLE obtained by the altimeter observations along ground tracks, after subtraction of the tidal components. In order to test the methodology, eleven storm surge events recorded in Venice, from 2008 to 2012, have been simulated using different configurations of forcing wind and altimeter data assimilation. Results show that the relative error on the estimation of the maximum surge peak, averaged over the cases considered, decreases from 13% to 7% using both the unbiased wind and the altimeter data assimilation, while forcing the hydrodynamic model with the high resolution wind (no tuning), the altimeter data assimilation reduces the error from 9% to 6%.

Impact of using scatterometer and altimeter data on storm surge forecasting

NASA Astrophysics Data System (ADS)

Bajo, Marco; De Biasio, Francesco; Umgiesser, Georg; Vignudelli, Stefano; Zecchetto, Stefano

2017-05-01

Satellite data are rarely used in storm surge models because of the lack of established methodologies. Nevertheless, they can provide useful information on surface wind and sea level, which can potentially improve the forecast. In this paper satellite wind data are used to correct the bias of wind originating from a global atmospheric model, while satellite sea level data are used to improve the initial conditions of the model simulations. In a first step, the capability of global winds (biased and unbiased) to adequately force a storm surge model are assessed against that of a high resolution local wind. Then, the added value of direct assimilation of satellite altimeter data in the storm surge model is tested. Eleven storm surge events, recorded in Venice from 2008 to 2012, are simulated using different configurations of wind forcing and altimeter data assimilation. Focusing on the maximum surge peak, results show that the relative error, averaged over the eleven cases considered, decreases from 13% to 7%, using both the unbiased wind and assimilating the altimeter data, while, if the high resolution local wind is used to force the hydrodynamic model, the altimeter data assimilation reduces the error from 9% to 6%. Yet, the overall capabilities in reproducing the surge in the first day of forecast, measured by the correlation and by the rms error, improve only with the use of the unbiased global wind and not with the use of high resolution local wind and altimeter data assimilation.

Adapting NEMO for use as the UK operational storm surge forecasting model

NASA Astrophysics Data System (ADS)

Furner, Rachel; Williams, Jane; Horsburgh, Kevin; Saulter, Andrew

2016-04-01

The United Kingdom is an area vulnerable to damage due to storm surges, particularly the East Coast which suffered losses estimated at over £1 billion during the North Sea surge event of the 5th and 6th December 2013. Accurate forecasting of storm surge events for this region is crucial to enable government agencies to assess the risk of overtopping of coastal defences so they can respond appropriately, minimising risk to life and infrastructure. There has been an operational storm surge forecast service for this region since 1978, using a numerical model developed by the National Oceanography Centre (NOC) and run at the UK Met Office. This is also implemented as part of an ensemble prediction system, using perturbed atmospheric forcing to produce an ensemble surge forecast. In order to ensure efficient use of future supercomputer developments and to create synergy with existing operational coastal ocean models the Met Office and NOC have begun a joint project transitioning the storm surge forecast system from the current CS3X code base to a configuration based on the Nucleus for European Modelling of the Ocean (NEMO). This work involves both adapting NEMO to add functionality, such as allowing the drying out of ocean cells and changes allowing NEMO to run efficiently as a two-dimensional, barotropic model. As the ensemble surge forecast system is run with 12 members 4 times a day computational efficiency is of high importance. Upon completion this project will enable interesting scientific comparisons to be made between a NEMO based surge model and the full three-dimensional baroclinic NEMO based models currently run within the Met Office, facilitating assessment of the impact of baroclinic processes, and vertical resolution on sea surface height forecasts. Moving to a NEMO code base will also allow many future developments to be more easily used within the storm surge model due to the wide range of options which currently exist within NEMO or are planned for future NEMO releases, such as data assimilation, and surge-wave coupling. Assessment of tidal performance of the NEMO-surge configuration and comparison to the existing operational CS3X model has been carried out. Evaluation of the models focus on performance relative to the UK Class A tide gauge network, a dataset which was established following the devastating flood of 1953 and which is managed by the British Oceanographic Data Service (BODC) based at NOC. Trials of the NEMO model in tide-only mode have illustrated the importance of having a well specified bathymetry and, for the 7km scaled model, a secondary sensitivity to bed friction coefficient and the specification of the coastline. Preliminary results will also be presented from model runs with atmospheric (wind stress and pressure at mean sea-level) forcing.

Determination of Dimensionless Attenuation Coefficient in Shaped Resonators

NASA Technical Reports Server (NTRS)

Daniels, C.; Steinetz, B.; Finkbeiner, J.; Raman, G.; Li, X.

2003-01-01

The value of dimensionless attenuation coefficient is an important factor when numerically predicting high-amplitude acoustic waves in shaped resonators. Both the magnitude of the pressure waveform and the quality factor rely heavily on this dimensionless parameter. Previous authors have stated the values used, but have not completely explained their methods. This work fully describes the methodology used to determine this important parameter. Over a range of frequencies encompassing the fundamental resonance, the pressure waves were experimentally measured at each end of the shaped resonators. At the corresponding dimensionless acceleration, the numerical code modeled the acoustic waveforms generated in the resonator using various dimensionless attenuation coefficients. The dimensionless attenuation coefficient that most closely matched the pressure amplitudes and quality factors of the experimental and numerical results was determined to be the value to be used in subsequent studies.

Induction of ovarian cystic follicles in sheep.

PubMed

Christman, S A; Bailey, M T; Head, W A; Wheaton, J E

2000-10-01

Cystic follicles are a significant cause of infertility in women, dairy cattle and sheep. Sheep were used as a model to identify factors that may elicit formation of cystic follicles. Insulin resistance and elevated LH activity were tested in overweight ewes because of associations among these factors and the formation of cystic follicles. Sheep were synchronized using a progesterone-releasing pessary and insulin resistance was induced during the synchronization period through administration of bovine somatotropin. Following removal of pessaries follicular growth was stimulated by treatment with eCG or eCG and hCG (PG-600). Follicular growth was monitored via daily transrectal ultrasonography and blood samples were collected for hormonal analyses. Six of 18 ewes had a subnormal or absent preovulatory gonadotropin surge and developed cystic follicles. Neither insulin resistance nor elevated LH activity were associated with formation of cystic follicles. Ewes that developed cystic follicles were heavier (93 +/- 4 kg) than ewes that ovulated (81 +/- 3 kg; P = 0.02). Furthermore, following pessary removal and initiation of daily ultrasonography, ewes that developed cystic follicles lost body weight (-3 +/- 1%), while ovulatory ewes continued to gain body weight (1 +/- 1%; P = 0.005). It is speculated that in heavy ewes metabolic factors associated with acute body weight loss inhibit the positive feedback of estradiol and thereby suppress the preovulatory gonadotropin surge leading to formation of cystic follicles.

40 CFR Table 2 to Subpart H of... - Surge Control Vessels and Bottoms Receivers at Existing Sources

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 9 2010-07-01 2010-07-01 false Surge Control Vessels and Bottoms Receivers at Existing Sources 2 Table 2 to Subpart H of Part 63 Protection of Environment ENVIRONMENTAL... Equipment Leaks Pt. 63, Subpt. H, Table 2 Table 2 to Subpart H of Part 63—Surge Control Vessels and Bottoms...

40 CFR Table 3 to Subpart H of... - Surge Control Vessels and Bottoms Receivers at New Sources

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 9 2010-07-01 2010-07-01 false Surge Control Vessels and Bottoms Receivers at New Sources 3 Table 3 to Subpart H of Part 63 Protection of Environment ENVIRONMENTAL... Equipment Leaks Pt. 63, Subpt. H, Table 3 Table 3 to Subpart H of Part 63—Surge Control Vessels and Bottoms...

Assessment of the Great Lakes Marine Renewable Energy Resources: Characterizing Lake Erie Surge, Seiche and Waves

NASA Astrophysics Data System (ADS)

Farhadzadeh, A.; Hashemi, M. R.

2016-02-01

Lake Erie, the fourth largest in surface area, smallest in volume and shallowest among the Great Lakes is approximately 400 km long and 90 km wide. Short term lake level variations are due to storm surge generated by high winds and moving pressure systems over the lake mainly in the southwest-northeast direction, along the lakes longitudinal axis. The historical wave data from three active offshore buoys shows that significant wave height can exceed 5 m in the eastern and central basins. The long-term lake level data show that storm surge can reach up to 3 m in eastern Lake Erie. Owing its shallow depth, Lake Erie frequently experiences seiching motions, the low frequency oscillations that are initiated by storm surge. The seiches whose first mode of oscillations has a period of nearly 14.2 hours can last from several hours to days. In this study, the Lake Erie potential for power generation, primarily using storm surge and seiche and also waves are assessed. Given the cyclic lake level variations due to storm-induced seiching, a concept similar to that of tidal range development is utilized to assess the potential of storm surge and seiche energy harvesting mechanisms for power generation. In addition, wave energy resources of the Lake is characterized -. To achieve these objectives, the following steps are taken : (1) Frequency of occurrence for extreme storm surge and wave events is determined using extreme value analysis such as Peak-Over-Threshold method for the long-term water level and wave data; (2) Spatial and temporal variations of wave height, storm surge and seiche are characterized. The characterization is carried out using the wave and storm surge outputs from numerical simulation of a number of historical extreme events. The coupled ADCIRC and SWAN model is utilized for the modeling; (3) Assessment of the potentials for marine renewable power generation in Lake Erie is made. The approach can be extended to the other lakes in the Great Lakes region.

Impacts of Storm Surge Mitigation Strategies on Aboveground Storage Tank Chemical Spill Transport

NASA Astrophysics Data System (ADS)

Do, C.; Bass, B. J.; Bernier, C.; Samii, A.; Dawson, C.; Bedient, P. B.

2017-12-01

The Houston Ship Channel (HSC), located in the hurricane-prone Houston-Galveston region of the upper Texas Coast, is one of the busiest waterways in the United States and is home to one of the largest petrochemical complexes in the world. Due to the proximity of the HSC to Galveston Bay and the Gulf of Mexico, chemical spills resulting from storm surge damage to aboveground storage tanks (ASTs) pose serious threats to the environment, residential communities, and national/international markets whose activities in the HSC generate billions of dollars annually. In an effort to develop a comprehensive storm surge mitigation strategy for Galveston Bay and its constituents, Rice University's Severe Storm Prediction, Education, and Evacuation from Disasters Center proposed two structural storm surge mitigation concepts, the Mid Bay Structure (MBS) and the Lower Bay Structure (LBS) as components of the Houston-Galveston Area Protection System (H-GAPS) project. The MBS consists of levees along the HSC and a navigational gate across the channel, and the LBS consists of a navigation gate and environmental gates across Bolivar Road. The impacts of these two barrier systems on the fate of AST chemical spills in the HSC have previously been unknown. This study applies the coupled 2D SWAN+ADCIRC model to simulate hurricane storm surge circulation within the Gulf of Mexico and Galveston Bay due to a synthetic storm which results in approximately 250-year surge levels in Galveston Bay. The SWAN+ADCIRC model is run using high-resolution computational meshes that incorporate the MBS and LBS scenarios, separately. The resulting wind and water velocities are then fed into a Lagrangian particle transport model to simulate the spill trajectories of the ASTs most likely to fail during the 250-year proxy storm. Results from this study illustrate how each storm surge mitigation strategy impacts the transport of chemical spills (modeled as Lagrangian particles) during storm surge as compared to the base case with only currently existing mitigation features in place. This study is part of a larger effort to evaluate the costs and benefits of several storm surge mitigation configurations proposed by the H-GAPS project.

Discontinuous Galerkin methods for modeling Hurricane storm surge

NASA Astrophysics Data System (ADS)

Dawson, Clint; Kubatko, Ethan J.; Westerink, Joannes J.; Trahan, Corey; Mirabito, Christopher; Michoski, Craig; Panda, Nishant

2011-09-01

Storm surge due to hurricanes and tropical storms can result in significant loss of life, property damage, and long-term damage to coastal ecosystems and landscapes. Computer modeling of storm surge can be used for two primary purposes: forecasting of surge as storms approach land for emergency planning and evacuation of coastal populations, and hindcasting of storms for determining risk, development of mitigation strategies, coastal restoration and sustainability. Storm surge is modeled using the shallow water equations, coupled with wind forcing and in some events, models of wave energy. In this paper, we will describe a depth-averaged (2D) model of circulation in spherical coordinates. Tides, riverine forcing, atmospheric pressure, bottom friction, the Coriolis effect and wind stress are all important for characterizing the inundation due to surge. The problem is inherently multi-scale, both in space and time. To model these problems accurately requires significant investments in acquiring high-fidelity input (bathymetry, bottom friction characteristics, land cover data, river flow rates, levees, raised roads and railways, etc.), accurate discretization of the computational domain using unstructured finite element meshes, and numerical methods capable of capturing highly advective flows, wetting and drying, and multi-scale features of the solution. The discontinuous Galerkin (DG) method appears to allow for many of the features necessary to accurately capture storm surge physics. The DG method was developed for modeling shocks and advection-dominated flows on unstructured finite element meshes. It easily allows for adaptivity in both mesh ( h) and polynomial order ( p) for capturing multi-scale spatial events. Mass conservative wetting and drying algorithms can be formulated within the DG method. In this paper, we will describe the application of the DG method to hurricane storm surge. We discuss the general formulation, and new features which have been added to the model to better capture surge in complex coastal environments. These features include modifications to the method to handle spherical coordinates and maintain still flows, improvements in the stability post-processing (i.e. slope-limiting), and the modeling of internal barriers for capturing overtopping of levees and other structures. We will focus on applications of the model to recent events in the Gulf of Mexico, including Hurricane Ike.

Coordinated Regulation Among Progesterone, Prostaglandins, and EGF-Like Factors in Human Ovulatory Follicles.

PubMed

Choi, Yohan; Wilson, Kalin; Hannon, Patrick R; Rosewell, Katherine L; Brännström, Mats; Akin, James W; Curry, Thomas E; Jo, Misung

2017-06-01

In animal models, the luteinizing hormone surge increases progesterone (P4) and progesterone receptor (PGR), prostaglandins (PTGs), and epidermal growth factor (EGF)-like factors that play essential roles in ovulation. However, little is known about the expression, regulation, and function of these key ovulatory mediators in humans. To determine when and how these key ovulatory mediators are induced after the luteinizing hormone surge in human ovaries. Timed periovulatory follicles were obtained from cycling women. Granulosa/lutein cells were collected from in vitro fertilization patients. The in vivo and in vitro expression of PGR, PTG synthases and transporters, and EGF-like factors were examined at the level of messenger RNA and protein. PGR binding to specific genes was assessed. P4 and PTGs in conditioned media were measured. PGR, PTGS2, and AREG expressions dramatically increased in ovulatory follicles at 12 to 18 hours after human chorionic gonadotropin (hCG). In human granulosa/lutein cell cultures, hCG increased P4 and PTG production and the expression of PGR, specific PTG synthases and transporters, and EGF-like factors, mimicking in vivo expression patterns. Inhibitors for P4/PGR and EGF-signaling pathways reduced hCG-induced increases in PTG production and the expression of EGF-like factors. PGR bound to the PTGS2, PTGES, and SLCO2A1 genes. This report demonstrated the time-dependent induction of PGR, AREG, and PTGS2 in human periovulatory follicles. In vitro studies indicated that collaborative actions of P4/PGR and EGF signaling are required for hCG-induced increases in PTG production and potentiation of EGF signaling in human periovulatory granulosa cells. Copyright © 2017 Endocrine Society

Coordinated Regulation Among Progesterone, Prostaglandins, and EGF-Like Factors in Human Ovulatory Follicles

PubMed Central

Choi, Yohan; Wilson, Kalin; Hannon, Patrick R.; Rosewell, Katherine L.; Brännström, Mats; Akin, James W.; Curry, Thomas E.

2017-01-01

Context: In animal models, the luteinizing hormone surge increases progesterone (P4) and progesterone receptor (PGR), prostaglandins (PTGs), and epidermal growth factor (EGF)–like factors that play essential roles in ovulation. However, little is known about the expression, regulation, and function of these key ovulatory mediators in humans. Objective: To determine when and how these key ovulatory mediators are induced after the luteinizing hormone surge in human ovaries. Design and Participants: Timed periovulatory follicles were obtained from cycling women. Granulosa/lutein cells were collected from in vitro fertilization patients. Main Outcome Measures: The in vivo and in vitro expression of PGR, PTG synthases and transporters, and EGF-like factors were examined at the level of messenger RNA and protein. PGR binding to specific genes was assessed. P4 and PTGs in conditioned media were measured. Results: PGR, PTGS2, and AREG expressions dramatically increased in ovulatory follicles at 12 to 18 hours after human chorionic gonadotropin (hCG). In human granulosa/lutein cell cultures, hCG increased P4 and PTG production and the expression of PGR, specific PTG synthases and transporters, and EGF-like factors, mimicking in vivo expression patterns. Inhibitors for P4/PGR and EGF-signaling pathways reduced hCG-induced increases in PTG production and the expression of EGF-like factors. PGR bound to the PTGS2, PTGES, and SLCO2A1 genes. Conclusions: This report demonstrated the time-dependent induction of PGR, AREG, and PTGS2 in human periovulatory follicles. In vitro studies indicated that collaborative actions of P4/PGR and EGF signaling are required for hCG-induced increases in PTG production and potentiation of EGF signaling in human periovulatory granulosa cells. PMID:28323945

Caffeine's Attenuation of Cocaine-Induced Dopamine Release by Inhibition of Adenosine.

PubMed

Malave, Lauren B; Broderick, Patricia A

2014-06-01

Background: It is well known that the reinforcing properties of cocaine addiction are caused by the sharp increase of dopamine (DA) in the reward areas of the brain. However, other mechanisms have been speculated to contribute to the increase. Adenosine is one system that is associated with the sleep-wake cycle and is most important in regulating neuronal activity. Thus, more and more evidence is pointing to its involvement in regulating DA release. The current study set out to examine the role of adenosine in cocaine-induced DA release. Methods: Increasing doses of cocaine, caffeine, and their combination, as well as, 8-cyclopentyltheophylline (CPT), an adenosine A1 antagonist (alone and in combination with cocaine) were used to denote a response curve. A novel biosensor, the BRODERICK PROBE ® was implanted in the nucleus accumbens to image the drug-induced surge of DA release in vivo , in the freely moving animal in real time. Results: Combinations of cocaine and caffeine were observed to block the increased release of DA moderately after administration of the low dose (2.5 mg/kg cocaine and 12.5 mg/kg caffeine) and dramatically after administration of the high dose (10 mg/kg cocaine and 50 mg/kg caffeine), suggesting neuroprotection. Similarly, CPT and cocaine showed a decreased DA surge when administered in combination. Thus, the low and high dose of a nonselective adenosine antagonist, caffeine, and a moderate dose of a selective adenosine antagonist, CPT, protected against the cocaine-induced DA release. Conclusions: These results show a significant interaction between adenosine and DA release and suggest therapeutic options for cocaine addiction and disorders associated with DA dysfunction.

Caffeine's Attenuation of Cocaine-Induced Dopamine Release by Inhibition of Adenosine

PubMed Central

Malave, Lauren B.

2014-01-01

Background: It is well known that the reinforcing properties of cocaine addiction are caused by the sharp increase of dopamine (DA) in the reward areas of the brain. However, other mechanisms have been speculated to contribute to the increase. Adenosine is one system that is associated with the sleep-wake cycle and is most important in regulating neuronal activity. Thus, more and more evidence is pointing to its involvement in regulating DA release. The current study set out to examine the role of adenosine in cocaine-induced DA release. Methods: Increasing doses of cocaine, caffeine, and their combination, as well as, 8-cyclopentyltheophylline (CPT), an adenosine A1 antagonist (alone and in combination with cocaine) were used to denote a response curve. A novel biosensor, the BRODERICK PROBE® was implanted in the nucleus accumbens to image the drug-induced surge of DA release in vivo, in the freely moving animal in real time. Results: Combinations of cocaine and caffeine were observed to block the increased release of DA moderately after administration of the low dose (2.5 mg/kg cocaine and 12.5 mg/kg caffeine) and dramatically after administration of the high dose (10 mg/kg cocaine and 50 mg/kg caffeine), suggesting neuroprotection. Similarly, CPT and cocaine showed a decreased DA surge when administered in combination. Thus, the low and high dose of a nonselective adenosine antagonist, caffeine, and a moderate dose of a selective adenosine antagonist, CPT, protected against the cocaine-induced DA release. Conclusions: These results show a significant interaction between adenosine and DA release and suggest therapeutic options for cocaine addiction and disorders associated with DA dysfunction. PMID:25054079

Determination of 210Pb concentration in NORM waste - An application of the transmission method for self-attenuation corrections for gamma-ray spectrometry

NASA Astrophysics Data System (ADS)

Bonczyk, Michal

2018-07-01

This article deals with the problem of the self-attenuation of low-energy gamma-rays from the isotope of lead 210Pb (46.5 keV) in industrial waste. The 167 samples of industrial waste, belonging to nine categories, were tested by means of gamma spectrometry in order to determine 210Pb activity concentration. The experimental method for self-attenuation corrections for gamma rays emitted by lead isotope was applied. Mass attenuation coefficients were determined for energy of 46.5 keV. Correction factors were calculated based on mass attenuation coefficients, sample density and thickness. A mathematical formula for correction calculation was evaluated. The 210Pb activity concentration obtained varied in the range from several Bq·kg-1 up to 19,810 Bq kg-1. The mass attenuation coefficients varied across the range of 0.19-4.42 cm2·g-1. However, the variation of mass attenuation coefficient within some categories of waste was relatively small. The calculated corrections for self-attenuation were 0.98 - 6.97. The high value of correction factors must not be neglect in radiation risk assessment.

2001 Bhuj, India, earthquake engineering seismoscope recordings and Eastern North America ground-motion attenuation relations

USGS Publications Warehouse

Cramer, C.H.; Kumar, A.

2003-01-01

Engineering seismoscope data collected at distances less than 300 km for the M 7.7 Bhuj, India, mainshock are compatible with ground-motion attenuation in eastern North America (ENA). The mainshock ground-motion data have been corrected to a common geological site condition using the factors of Joyner and Boore (2000) and a classification scheme of Quaternary or Tertiary sediments or rock. We then compare these data to ENA ground-motion attenuation relations. Despite uncertainties in recording method, geological site corrections, common tectonic setting, and the amount of regional seismic attenuation, the corrected Bhuj dataset agrees with the collective predictions by ENA ground-motion attenuation relations within a factor of 2. This level of agreement is within the dataset uncertainties and the normal variance for recorded earthquake ground motions.

Recurrence of stroke caused by nocturnal hypoxia-induced blood pressure surge in a young adult male with severe obstructive sleep apnea syndrome.

PubMed

Yoshida, Tetsuro; Kuwabara, Mitsuo; Hoshide, Satoshi; Kario, Kazuomi

2016-03-01

Obstructive sleep apnea syndrome (OSAS) causes resistant hypertension and a hypopnea-related nocturnal blood pressure (BP) surge. This could lead to an increase of not only the nocturnal BP level but also nocturnal BP variability, both of which increase an individual's cardiovascular risk. We recently developed a trigger sleep BP monitoring method that initiates BP measurement when an individual's oxygen desaturation falls below a variable threshold, and we demonstrated that it can detect a BP surge during apnea episodes. We here report the case of a 36-year-old man with severe OSAS who experienced the recurrence of stroke due to nocturnal hypoxia and a nocturnal BP surge measured by this trigger sleep BP monitoring device. A nocturnal BP surge during sleep in OSAS patients could be a strong trigger of cardiovascular events. Copyright © 2016 American Society of Hypertension. Published by Elsevier Inc. All rights reserved.

Current & future vulnerability of sarasota county Florida to hurricane storm surge & sea level rise

USGS Publications Warehouse

Frazier, T.; Wood, N.; Yarnal, B.

2008-01-01

Coastal communities in portions of the United States are vulnerable to storm-surge inundation from hurricanes and this vulnerability will likely increase, given predicted rises in sea level from climate change and growing coastal development. In this paper, we provide an overview of research to determine current and future societal vulnerability to hurricane storm-surge inundation and to help public officials and planners integrate these scenarios into their long-range land use plans. Our case study is Sarasota County, Florida, where planners face the challenge of balancing increasing population growth and development with the desire to lower vulnerability to storm surge. Initial results indicate that a large proportion of Sarasota County's residential and employee populations are in areas prone to storm-surge inundation from a Category 5 hurricane. This hazard zone increases when accounting for potential sea-level-rise scenarios, thereby putting additional populations at risk. Subsequent project phases involve the development of future land use and vulnerability scenarios in collaboration with local officials. Copyright ASCE 2008.

Monitoring Inland Storm Surge and Flooding from Hurricane Rita

USGS Publications Warehouse

McGee, Benton D.; Tollett, Roland W.; Mason, Jr., Robert R.

2006-01-01

Pressure transducers (sensors) and high-water marks were used to document the inland water levels related to storm surge generated by Hurricane Rita in southwestern Louisiana and southeastern Texas. On September 22-23, 2005, an experimental monitoring network of sensors was deployed at 33 sites over an area of about 4,000 square miles to record the timing, extent, and magnitude of inland hurricane storm surge and coastal flooding. Sensors were programmed to record date and time, temperature, and barometric or water pressure. Water pressure was corrected for changes in barometric pressure and salinity. Elevation surveys using global-positioning systems and differential levels were used to relate all storm-surge water-level data, reference marks, benchmarks, sensor measuring points, and high-water marks to the North American Vertical Datum of 1988 (NAVD 88). The resulting data indicated that storm-surge water levels over 14 feet above NAVD 88 occurred at three locations, and rates of water-level rise greater than 5 feet per hour occurred at three locations near the Louisiana coast.

The group VIA calcium-independent phospholipase A2 and NFATc4 pathway mediates IL-1β-induced expression of chemokines CCL2 and CXCL10 in rat fibroblasts.

PubMed

Kuwata, Hiroshi; Yuzurihara, Chihiro; Kinoshita, Natsumi; Taki, Yuki; Ikegami, Yuki; Washio, Sana; Hirakawa, Yushi; Yoda, Emiko; Aiuchi, Toshihiro; Itabe, Hiroyuki; Nakatani, Yoshihito; Hara, Shuntaro

2018-06-01

Chemokines are secreted proteins that regulate cell migration and are involved in inflammatory and immune responses. Here, we sought to define the functional crosstalk between the lipid signaling and chemokine signaling. We obtained evidence that the induction of some chemokines is regulated by group VIA calcium-independent phospholipase A 2 β (iPLA 2 β) in IL-1β-stimulated rat fibroblastic 3Y1 cells. Treatment of 3Y1 cells with IL-1β elicited an increased release of chemotactic factor(s) for monocytic THP-1 cells into culture medium in a time-dependent manner. Inhibitor studies revealed that an intracellular PLA 2 inhibitor, arachidonoyl trifluoromethyl ketone (AACOCF 3 ), but not the cyclooxygenase inhibitor indomethacin, attenuated the release of chemotactic factor(s). The chemotactic activity was inactivated by treatment with either heat or proteinase K, suggesting this chemotactic factor(s) is a proteinaceous factor(s). We purified the chemotactic factor(s) from the conditioned medium of IL-1β-stimulated 3Y1 cells using a heparin column and identified several chemokines, including CCL2 and CXCL10. The inducible expressions of CCL2 and CXCL10 were significantly attenuated by pretreatment with AACOCF 3 . Gene silencing using siRNA revealed that the inductions of CCL2 and CXCL10 were attenuated by iPLA 2 β knockdown. Additionally, the transcriptional activation of nuclear factor of activated T-cell proteins (NFATs), but not nuclear factor-κB, by IL-1β stimulation was markedly attenuated by the iPLA 2 inhibitor bromoenol lactone, and NFATc4 knockdown markedly attenuated the IL-1β-induced expression of both CCL2 and CXCL10. Collectively, these results indicated that iPLA 2 β plays roles in IL-1β-induced chemokine expression, in part via NFATc4 signaling. © 2018 Federation of European Biochemical Societies.

Prehospital Blood Transfusion in the En Route Management of Severe Combat Trauma: A Matched Cohort Study

DTIC Science & Technology

2014-09-01

routine use of tranexamic acid and decreased recombinant activated factor VII use repre- sent the effects of opposing trends in the evidence base for...Respiratory rate 19 (15Y24) 20 (16Y26) 0.173** Heart rate 92 (74Y115) 105 (82Y128) 0.041** Tranexamic acid 22 (22.6) 0 (0) U/T Recombinant activated factor VII...Military Applica- tion of Tranexamic Acid in Trauma Emergency Resuscitation (MATTERs) study. Arch Surg. 2012;147(2):113Y119. 6. Penn-Barwell JG

Dynamical Influence and Operational Impacts of an Extreme Mediterranean Cold Surge

DTIC Science & Technology

2013-06-01

over 45 cm of snowfall in Souda Bay, Crete, which significantly impacted operations at Naval Support Activity Souda Bay. The extratropical wave...cold surge event and its dependence on the upstream synoptic scale events. 14. SUBJECT TERMS Extratropical Cyclone, Souda Bay...Activity Souda Bay. The extratropical wave associated with the cold surge could be classified as a classic life-cycle 1 wave break. The wave-breaking

Planning for partnerships: Maximizing surge capacity resources through service learning.

PubMed

Adams, Lavonne M; Reams, Paula K; Canclini, Sharon B

2015-01-01

Infectious disease outbreaks and natural or human-caused disasters can strain the community's surge capacity through sudden demand on healthcare activities. Collaborative partnerships between communities and schools of nursing have the potential to maximize resource availability to meet community needs following a disaster. This article explores how communities can work with schools of nursing to enhance surge capacity through systems thinking, integrated planning, and cooperative efforts.

Catastrophe loss modelling of storm-surge flood risk in eastern England.

PubMed

Muir Wood, Robert; Drayton, Michael; Berger, Agnete; Burgess, Paul; Wright, Tom

2005-06-15

Probabilistic catastrophe loss modelling techniques, comprising a large stochastic set of potential storm-surge flood events, each assigned an annual rate of occurrence, have been employed for quantifying risk in the coastal flood plain of eastern England. Based on the tracks of the causative extratropical cyclones, historical storm-surge events are categorized into three classes, with distinct windfields and surge geographies. Extreme combinations of "tide with surge" are then generated for an extreme value distribution developed for each class. Fragility curves are used to determine the probability and magnitude of breaching relative to water levels and wave action for each section of sea defence. Based on the time-history of water levels in the surge, and the simulated configuration of breaching, flow is time-stepped through the defences and propagated into the flood plain using a 50 m horizontal-resolution digital elevation model. Based on the values and locations of the building stock in the flood plain, losses are calculated using vulnerability functions linking flood depth and flood velocity to measures of property loss. The outputs from this model for a UK insurance industry portfolio include "loss exceedence probabilities" as well as "average annualized losses", which can be employed for calculating coastal flood risk premiums in each postcode.

Numerical Study of the Port of Miami (Importance of Dodge Island) in Storm Surge and Flooding Forecasting in North Biscayne Bay

NASA Astrophysics Data System (ADS)

Liu, H.; Zhang, K.; Li, Y.

2011-12-01

The importance of Port of Miami (Dodge Island) in storm surge and flooding forecasting in North Biscayne Bay was investigated by using the numerical model Coastal and Estuarine Storm Tide (CEST). Firstly, CEST was applied to Hurricane Andrew of 1992 in the Biscayne Bay basin and validated by in situ measurements, which indicated the model results had good agreement with measured data. Secondly, two sets of experiments using Hurricane Miami of 1926 were conducted to study the role of Dodge Island in storm surge and flooding forecasting in North Biscayne Bay: one set of experiments were run in today's Biscayne Bay basin and another set of experiments were run in Biscayne Bay basin of 1926 in which Dodge Island was not created yet. Results indicated that storm surge and flooding areas were reduced a little bit in Miami River areas when Dodge Island was not there. Meanwhile, storm surge and flooding areas in North Miami and Miami Beach regions were largely increased. Results further indicated that as long as the hurricane made landfall in south of Dodge Island, it can provide a good protection for Miami Beach area to reduce storm surge and flooding impacts.

Field Experience with Lock Culvert Valves

DTIC Science & Technology

2013-12-01

factors pertaining to valves such as the hoist loads, cavitation parameter, and effects of venting. To reduce the surge in the navigation channel...2 min 15 sec, filling-and-emptying valve opening time) ensures that adequate air is drawn into the culvert to cushion the cavitation implosions...shape can have adverse hydrodynamic loading consequences. The USACE, Mobile District (SAM) is in the process of designing replacement valves that are

Adolescent Inpatient Behavioral Health Clients: Risk Factors and Methods of Preventing an Increase in HIV Infection among Youth.

ERIC Educational Resources Information Center

Hackerman, Ann E.

2002-01-01

There has been a surge in the rates of adolescents who are becoming infected with HIV. This study of 214 at risk clients being treated on an inpatient psychiatric hospitalization basis examines why such clients continue to engage in high-risk behaviors. Results and suggestions for a psychoeducational curriculum for professionals are included.…

Frequency dependent Lg attenuation in south-central Alaska

USGS Publications Warehouse

McNamara, D.E.

2000-01-01

The characteristics of seismic energy attenuation are determined using high frequency Lg waves from 27 crustal earthquakes, in south-central Alaska. Lg time-domain amplitudes are measured in five pass-bands and inverted to determine a frequency-dependent quality factor, Q(f), model for south-central Alaska. The inversion in this study yields the frequency-dependent quality factor, in the form of a power law: Q(f) = Q0fη = 220(±30) f0.66(±0.09) (0.75≤f≤12Hz). The results from this study are remarkably consistent with frequency dependent quality factor estimates, using local S-wave coda, in south-central Alaska. The consistency between S-coda Q(f) and Lg Q(f) enables constraints to be placed on the mechanism of crustal attenuation in south-central Alaska. For the range of frequencies considered in this study both scattering and intrinsic attenuation mechanisms likely play an equal role.

Dynamic simulation and numerical analysis of hurricane storm surge under sea level rise with geomorphologic changes along the northern Gulf of Mexico

USGS Publications Warehouse

Bilskie, Matthew V.; Hagen, S.C.; Alizad, K.A.; Medeiros, S.C.; Passeri, Davina L.; Needham, H.F.; Cox, A.

2016-01-01

This work outlines a dynamic modeling framework to examine the effects of global climate change, and sea level rise (SLR) in particular, on tropical cyclone-driven storm surge inundation. The methodology, applied across the northern Gulf of Mexico, adapts a present day large-domain, high resolution, tide, wind-wave, and hurricane storm surge model to characterize the potential outlook of the coastal landscape under four SLR scenarios for the year 2100. The modifications include shoreline and barrier island morphology, marsh migration, and land use land cover change. Hydrodynamics of 10 historic hurricanes were simulated through each of the five model configurations (present day and four SLR scenarios). Under SLR, the total inundated land area increased by 87% and developed and agricultural lands by 138% and 189%, respectively. Peak surge increased by as much as 1 m above the applied SLR in some areas, and other regions were subject to a reduction in peak surge, with respect to the applied SLR, indicating a nonlinear response. Analysis of time-series water surface elevation suggests the interaction between SLR and storm surge is nonlinear in time; SLR increased the time of inundation and caused an earlier arrival of the peak surge, which cannot be addressed using a static (“bathtub”) modeling framework. This work supports the paradigm shift to using a dynamic modeling framework to examine the effects of global climate change on coastal inundation. The outcomes have broad implications and ultimately support a better holistic understanding of the coastal system and aid restoration and long-term coastal sustainability.

A numerical study on the effects of wave-current-surge interactions on the height and propagation of sea surface waves in Charleston Harbor during Hurricane Hugo 1989

NASA Astrophysics Data System (ADS)

Liu, Huiqing; Xie, Lian

2009-06-01

The effects of wave-current interactions on ocean surface waves induced by Hurricane Hugo in and around the Charleston Harbor and its adjacent coastal waters are examined by using a three-dimensional (3D) wave-current coupled modeling system. The 3D storm surge modeling component of the coupled system is based on the Princeton Ocean Model (POM), the wave modeling component is based on the third generation wave model, Simulating WAves Nearshore (SWAN), and the inundation model is adopted from [Xie, L., Pietrafesa, L. J., Peng, M., 2004. Incorporation of a mass-conserving inundation scheme into a three-dimensional storm surge model. J. Coastal Res., 20, 1209-1223]. The results indicate that the change of water level associated with the storm surge is the primary cause for wave height changes due to wave-surge interaction. Meanwhile, waves propagating on top of surge cause a feedback effect on the surge height by modulating the surface wind stress and bottom stress. This effect is significant in shallow coastal waters, but relatively small in offshore deep waters. The influence of wave-current interaction on wave propagation is relatively insignificant, since waves generally propagate in the direction of the surface currents driven by winds. Wave-current interactions also affect the surface waves as a result of inundation and drying induced by the storm. Waves break as waters retreat in regions of drying, whereas waves are generated in flooded regions where no waves would have occurred without the flood water.

The Development of High-speed Full-function Storm Surge Model and the Case Study of 2013 Typhoon Haiyan

NASA Astrophysics Data System (ADS)

Tsai, Y. L.; Wu, T. R.; Lin, C. Y.; Chuang, M. H.; Lin, C. W.

2016-02-01

An ideal storm surge operational model should feature as: 1. Large computational domain which covers the complete typhoon life cycle. 2. Supporting both parametric and atmospheric models. 3. Capable of calculating inundation area for risk assessment. 4. Tides are included for accurate inundation simulation. Literature review shows that not many operational models reach the goals for the fast calculation, and most of the models have limited functions. In this paper, a well-developed COMCOT (COrnell Multi-grid Coupled of Tsunami Model) tsunami model is chosen as the kernel to establish a storm surge model which solves the nonlinear shallow water equations on both spherical and Cartesian coordinates directly. The complete evolution of storm surge including large-scale propagation and small-scale offshore run-up can be simulated by nested-grid scheme. The global tide model TPXO 7.2 established by Oregon State University is coupled to provide astronomical boundary conditions. The atmospheric model named WRF (Weather Research and Forecasting Model) is also coupled to provide metrological fields. The high-efficiency thin-film method is adopted to evaluate the storm surge inundation. Our in-house model has been optimized by OpenMp (Open Multi-Processing) with the performance which is 10 times faster than the original version and makes it an early-warning storm surge model. In this study, the thorough simulation of 2013 Typhoon Haiyan is performed. The detailed results will be presented in Oceanic Science Meeting of 2016 in terms of surge propagation and high-resolution inundation areas.

Sensitivity of Hurricane Storm Surge to Land Cover and Topography Under Various Sea Level Rise Scenarios Along the Mississippi Coast

NASA Astrophysics Data System (ADS)

Bilskie, M. V.; Hagen, S. C.; Medeiros, S. C.

2013-12-01

Major Gulf hurricanes have a high probability of impacting the northern Gulf of Mexico, especially coastal Mississippi (Resio, 2007). Due to the wide and flat continental shelf, this area provides near-perfect geometry for high water levels under tropical cyclone conditions. Literature suggests with 'very high confidence that global sea level will rise at least 0.2 m and no more than 2.0 m by 2011' (Donoghue, 2011; Parris et al., 2012). Further, it is recognized that the Mississippi barrier islands are highly susceptible to a westward migration and retreating shoreline. With predictions for less frequent, more intense tropical storms, rising sea levels, and a changing landscape, it is important to understand how these changes may affect inundation extent and flooding due to hurricane storm surge. A state-of-the-art SWAN+ADCIRC hydrodynamic model of coastal Mississippi was utilized to simulate Hurricane Katrina with present day sea level conditions. Using present day as a base scenario, past (1960) and future (2050) sea level changes were simulated. In addition to altering the initial sea state, land use land cover (LULC) was modified for 1960 and 2050 based on historic data and future projections. LULC datasets are used to derive surface roughness characteristics, such as Manning's n, and wind reduction factors. The topography along the barrier islands and near the Pascagoula River, MS was also altered to reflect the 1960 landscape. Storm surge sensitivity to topographic change were addressed by comparing model results between two 1960 storm surge simulations; one with current topography and a second with changes to the barrier islands. In addition, model responses to changes in LULC are compared. The results will be used to gain insight into adapting present day storm surge models for future conditions. References Donoghue, J. (2011). Sea level history of the northern Gulf of Mexico coast and sea level rise scenarios for the near future. Climatic Change, 107(1-2), 17-33. doi: 10.1007/s10584-011-0077-x Parris, A., Bromirski, P., Burkett, V., Cayan, D., Culver, M., Hall, J., . . . Weiss, J. (2012). Global Sea Level Rise Scenarios for the United States National Climate Assessment NOAA Tech Memo OAR CPO-1 (pp. 37). Resio, D. T. (2007). White paper on estimating hurricane inundation probabilities (pp. 125). Vicksburg, MS: U.S. Army Engineering Research and Development Center.

Mapping infectious disease hospital surge threats to lessons learnt in Singapore: a systems analysis and development of a framework to inform how to DECIDE on planning and response strategies.

PubMed

Singh, Shweta R; Coker, Richard; Vrijhoef, Hubertus J-M; Leo, Yee Sin; Chow, Angela; Lim, Poh Lian; Tan, Qinghui; Chen, Mark I-Cheng; Hildon, Zoe Jane-Lara

2017-09-04

Hospital usage and service demand during an Infectious Disease (ID) outbreak can tax the health system in different ways. Herein we conceptualize hospital surge elements, and lessons learnt from such events, to help build appropriately matched responses to future ID surge threats. We used the Interpretive Descriptive qualitative approach. Interviews (n = 35) were conducted with governance and public health specialists; hospital based staff; and General Practitioners. Key policy literature in tandem with the interview data were used to iteratively generate a Hospital ID Surge framework. We anchored our narrative account within this framework, which is used to structure our analysis. A spectrum of surge threats from combinations of capacity (for crowding) and capability (for treatment complexity) demands were identified. Starting with the Pyramid scenario, or an influx of high screening rates flooding Emergency Departments, alongside fewer and manageable admissions; the Reverse-Pyramid occurs when few cases are screened and admitted but those that are, are complex; during a 'Black' scenario, the system is overburdened by both crowding and complexity. The Singapore hospital system is highly adapted to crowding, functioning remarkably well at constant near-full capacity in Peacetime and resilient to Endemic surges. We catalogue 26 strategies from lessons learnt relating to staffing, space, supplies and systems, crystalizing institutional memory. The DECIDE model advocates linking these strategies to types of surge threats and offers a step-by-step guide for coordinating outbreak planning and response. Lack of a shared definition and decision making of surge threats had rendered the procedures somewhat duplicative. This burden was paradoxically exacerbated by a health system that highly prizes planning and forward thinking, but worked largely in silo until an ID crisis hit. Many such lessons can be put into play to further strengthen our current hospital governance and adapted to more diverse settings.

Integrated plan to augment surge capacity.

PubMed

Dayton, Christopher; Ibrahim, Jamil; Augenbraun, Michael; Brooks, Steven; Mody, Kiaran; Holford, Donald; Roblin, Patricia; Arquilla, Bonnie

2008-01-01

Surge capacity is defined as a healthcare system's ability to rapidly expand beyond normal services to meet the increased demand for appropriate space, qualified personnel, medical care, and public health in the event ofbioterrorism, disaster, or other large-scale, public health emergencies. There are many individuals and agencies, including policy makers, planners, administrators, and staff at the federal, state, and local level, involved in the process of planning for and executing policy in respect to a surge in the medical requirements of a population. They are responsible to ensure there is sufficient surge capacity within their own jurisdiction. The [US] federal government has required New York State to create a system of hospital bed surge capacity that provides for 500 adult and pediatric patients per 1 million population, which has been estimated to be an increase of 15-20% in bed availability. In response, the New York City Department of Health and Mental Hygiene (NYC DOH) has requested that area hospitals take an inventory of available beds and set a goal to provide for a 20% surge capacity to be available during a mass-casualty event or other conditions calling for increased inpatient bed availability. In 2003, under the auspices of the NYC DOH, the New York Institute of All Hazard Preparedness (NYIHP) was formed from four unaffiliated, healthcare facilities in Central Brooklyn to address this and other goals. The NYIHP hospitals have developed a surge capacity plan to provide necessary space and utilities. As these plans have been applied, a bed surge capacity of approximately 25% was identified and created for Central Brooklyn to provide for the increased demand on the medical care system that may accompany a disaster. Through the process of developing an integrated plan that would engage a public health incident, the facilities of NYIHP demonstrate that a model of cooperation may be applied to an inherently fractioned medical system.

METHOD AND LOCATION OF GROUND WATER SAMPLING: IMPACT ON ATTENUATION FACTORS FOR ASSESSING IMPACT ON VAPOR INTRUSION

EPA Science Inventory

The Draft EPA Subsurface Vapor Intrusion Guidance Document was established to "address the incremental increases in exposures and risks from subsurface contaminants that my be intruding into indoor air". The document utilizes attenuation factors based on indoor air/soil gas or i...

Coastal Adaptation Planning for Sea Level Rise and Extremes: A Global Model for Adaptation Decision-making at the Local Level Given Uncertain Climate Projections

NASA Astrophysics Data System (ADS)

Turner, D.

2014-12-01

Understanding the potential economic and physical impacts of climate change on coastal resources involves evaluating a number of distinct adaptive responses. This paper presents a tool for such analysis, a spatially-disaggregated optimization model for adaptation to sea level rise (SLR) and storm surge, the Coastal Impact and Adaptation Model (CIAM). This decision-making framework fills a gap between very detailed studies of specific locations and overly aggregate global analyses. While CIAM is global in scope, the optimal adaptation strategy is determined at the local level, evaluating over 12,000 coastal segments as described in the DIVA database (Vafeidis et al. 2006). The decision to pursue a given adaptation measure depends on local socioeconomic factors like income, population, and land values and how they develop over time, relative to the magnitude of potential coastal impacts, based on geophysical attributes like inundation zones and storm surge. For example, the model's decision to protect or retreat considers the costs of constructing and maintaining coastal defenses versus those of relocating people and capital to minimize damages from land inundation and coastal storms. Uncertain storm surge events are modeled with a generalized extreme value distribution calibrated to data on local surge extremes. Adaptation is optimized for the near-term outlook, in an "act then learn then act" framework that is repeated over the model time horizon. This framework allows the adaptation strategy to be flexibly updated, reflecting the process of iterative risk management. CIAM provides new estimates of the economic costs of SLR; moreover, these detailed results can be compactly represented in a set of adaptation and damage functions for use in integrated assessment models. Alongside the optimal result, CIAM evaluates suboptimal cases and finds that global costs could increase by an order of magnitude, illustrating the importance of adaptive capacity and coastal policy.

A probabilistic storm surge risk model for the German North Sea and Baltic Sea coast

NASA Astrophysics Data System (ADS)

Grabbert, Jan-Henrik; Reiner, Andreas; Deepen, Jan; Rodda, Harvey; Mai, Stephan; Pfeifer, Dietmar

2010-05-01

The German North Sea coast is highly exposed to storm surges. Due to its concave bay-like shape mainly orientated to the North-West, cyclones from Western, North-Western and Northern directions together with astronomical tide cause storm surges accumulating the water in the German bight. Due to the existence of widespread low-lying areas (below 5m above mean sea level) behind the defenses, large areas including large economic values are exposed to coastal flooding including cities like Hamburg or Bremen. The occurrence of extreme storm surges in the past like e.g. in 1962 taking about 300 lives and causing widespread flooding and 1976 raised the awareness and led to a redesign of the coastal defenses which provide a good level of protection for today's conditions. Never the less the risk of flooding exists. Moreover an amplification of storm surge risk can be expected under the influence of climate change. The Baltic Sea coast is also exposed to storm surges, which are caused by other meteorological patterns. The influence of the astronomical tide is quite low instead high water levels are induced by strong winds only. Since the exceptional extreme event in 1872 storm surge hazard has been more or less forgotten. Although such an event is very unlikely to happen, it is not impossible. Storm surge risk is currently (almost) non-insurable in Germany. The potential risk is difficult to quantify as there are almost no historical losses available. Also premiums are difficult to assess. Therefore a new storm surge risk model is being developed to provide a basis for a probabilistic quantification of potential losses from coastal inundation. The model is funded by the GDV (German Insurance Association) and is planned to be used within the German insurance sector. Results might be used for a discussion of insurance cover for storm surge. The model consists of a probabilistic event driven hazard and a vulnerability module, furthermore an exposure interface and a financial module to account for specific (re-) insurance conditions. This contribution will mainly concentrate on the hazard module. The hazard is covered by an event simulation engine enabling Monte Carlo simulations. The event generation is done on-the-fly. A classification of historical storm surges is used based on observed sea water levels at gauging stations and extended literature research. To characterize the origin of storm events and storm surges caused by those, also meteorological parameters like wind speed and wind direction are being used. If high water levels along the coast are mainly caused by strong wind from particular directions as observed at the North Sea, there is a clear empirical relationship between wind and surge (where surge is defined as the wind-driven component of the sea water level) which can be described by the ATWS (Average Transformed Wind speed). The parameters forming the load at the coastal defense elements are water level and wave parameters like significant wave height, wave period and wave direction. To assess the wave characteristics at the coast the numerical model SWAN (Simulating Waves Near Shore) from TU Delft has been used. To account for different probabilities of failure and inundation the coast is split into segments with similar defense characteristics like type of defense, height, width, orientation and others. The chosen approach covers the most relevant failure mechanisms for coastal dikes induced by wave overtopping and overflow. Dune failure is also considered in the model. Inundation of the hinterland after defense failure is modeled using a simple dynamical 2d-approach resulting in distributed water depths and flood outlines for each segment. Losses can be estimated depending on the input exposure data either coordinate based for single buildings or aggregated on postal code level using a set of depths-damage functions.

Comparison of hip geometry, strength, and estimated fracture risk in women with anorexia nervosa and overweight/obese women.

PubMed

Bachmann, Katherine Neubecker; Fazeli, Pouneh K; Lawson, Elizabeth A; Russell, Brian M; Riccio, Ariana D; Meenaghan, Erinne; Gerweck, Anu V; Eddy, Kamryn; Holmes, Tara; Goldstein, Mark; Weigel, Thomas; Ebrahimi, Seda; Mickley, Diane; Gleysteen, Suzanne; Bredella, Miriam A; Klibanski, Anne; Miller, Karen K

2014-12-01

Data suggest that anorexia nervosa (AN) and obesity are complicated by elevated fracture risk, but skeletal site-specific data are lacking. Traditional bone mineral density (BMD) measurements are unsatisfactory at both weight extremes. Hip structural analysis (HSA) uses dual-energy X-ray absorptiometry data to estimate hip geometry and femoral strength. Factor of risk (φ) is the ratio of force applied to the hip from a fall with respect to femoral strength; higher values indicate higher hip fracture risk. The objective of the study was to investigate hip fracture risk in AN and overweight/obese women. This was a cross-sectional study. The study was conducted at a Clinical Research Center. PATIENTS included 368 women (aged 19-45 y): 246 AN, 53 overweight/obese, and 69 lean controls. HSA-derived femoral geometry, peak factor of risk for hip fracture, and factor of risk for hip fracture attenuated by trochanteric soft tissue (φ(attenuated)) were measured. Most HSA-derived parameters were impaired in AN and superior in obese/overweight women vs controls at the narrow neck, intertrochanteric, and femoral shaft (P ≤ .03). The φ(attenuated) was highest in AN and lowest in overweight/obese women (P < .0001). Lean mass was associated with superior, and duration of amenorrhea with inferior, HSA-derived parameters and φ(attenuated) (P < .05). Mean φ(attenuated) (P = .036), but not femoral neck BMD or HSA-estimated geometry, was impaired in women who had experienced fragility fractures. Femoral geometry by HSA, hip BMD, and factor of risk for hip fracture attenuated by soft tissue are impaired in AN and superior in obesity, suggesting higher and lower hip fracture risk, respectively. Only attenuated factor of risk was associated with fragility fracture prevalence, suggesting that variability in soft tissue padding may help explain site-specific fracture risk not captured by BMD.

Comparison of Hip Geometry, Strength, and Estimated Fracture Risk in Women With Anorexia Nervosa and Overweight/Obese Women

PubMed Central

Bachmann, Katherine Neubecker; Fazeli, Pouneh K.; Lawson, Elizabeth A.; Russell, Brian M.; Riccio, Ariana D.; Meenaghan, Erinne; Gerweck, Anu V.; Eddy, Kamryn; Holmes, Tara; Goldstein, Mark; Weigel, Thomas; Ebrahimi, Seda; Mickley, Diane; Gleysteen, Suzanne; Bredella, Miriam A.; Klibanski, Anne

2014-01-01

Context: Data suggest that anorexia nervosa (AN) and obesity are complicated by elevated fracture risk, but skeletal site-specific data are lacking. Traditional bone mineral density (BMD) measurements are unsatisfactory at both weight extremes. Hip structural analysis (HSA) uses dual-energy X-ray absorptiometry data to estimate hip geometry and femoral strength. Factor of risk (φ) is the ratio of force applied to the hip from a fall with respect to femoral strength; higher values indicate higher hip fracture risk. Objective: The objective of the study was to investigate hip fracture risk in AN and overweight/obese women. Design: This was a cross-sectional study. Setting: The study was conducted at a Clinical Research Center. Patients: Patients included 368 women (aged 19–45 y): 246 AN, 53 overweight/obese, and 69 lean controls. Main Outcome Measures: HSA-derived femoral geometry, peak factor of risk for hip fracture, and factor of risk for hip fracture attenuated by trochanteric soft tissue (φattenuated) were measured. Results: Most HSA-derived parameters were impaired in AN and superior in obese/overweight women vs controls at the narrow neck, intertrochanteric, and femoral shaft (P ≤ .03). The φattenuated was highest in AN and lowest in overweight/obese women (P < .0001). Lean mass was associated with superior, and duration of amenorrhea with inferior, HSA-derived parameters and φattenuated (P < .05). Mean φattenuated (P = .036), but not femoral neck BMD or HSA-estimated geometry, was impaired in women who had experienced fragility fractures. Conclusions: Femoral geometry by HSA, hip BMD, and factor of risk for hip fracture attenuated by soft tissue are impaired in AN and superior in obesity, suggesting higher and lower hip fracture risk, respectively. Only attenuated factor of risk was associated with fragility fracture prevalence, suggesting that variability in soft tissue padding may help explain site-specific fracture risk not captured by BMD. PMID:25062461

First wide-angle view of channelized turbidity currents links migrating cyclic steps to flow characteristics

PubMed Central

Hughes Clarke, John E.

2016-01-01

Field observations of turbidity currents remain scarce, and thus there is continued debate about their internal structure and how they modify underlying bedforms. Here, I present the results of a new imaging method that examines multiple surge-like turbidity currents within a delta front channel, as they pass over crescent-shaped bedforms. Seven discrete flows over a 2-h period vary in speed from 0.5 to 3.0 ms−1. Only flows that exhibit a distinct acoustically attenuating layer at the base, appear to cause bedform migration. That layer thickens abruptly downstream of the bottom of the lee slope of the bedform, and the upper surface of the layer fluctuates rapidly at that point. The basal layer is inferred to reflect a strong near-bed gradient in density and the thickening is interpreted as a hydraulic jump. These results represent field-scale flow observations in support of a cyclic step origin of crescent-shaped bedforms. PMID:27283503

Non-Impact, Blast-Induced Mild TBI and PTSD: Concepts and Caveats

DTIC Science & Technology

2011-07-01

has been verified by wound ballistics experiments in animals and finite element simulation of blast loads on the torso. Blood surge caused by...ballistic pressure waves in animals An experimental study of wound ballistics demon- strates that a ballistic pressure wave can cause a remote injury to...surge. This hypothesis has been supported by some experimental data. A volumetric surge of blood moved through the thorax and abdomen has been observed

Effect of double air injection on performance characteristics of centrifugal compressor

NASA Astrophysics Data System (ADS)

Hirano, Toshiyuki; Ogawa, Tatsuya; Yasui, Ryutaro; Tsujita, Hoshio

2017-02-01

In the operation of a centrifugal compressor of turbocharger, instability phenomena such as rotating stall and surge are induced at a lower flow rate close to the maximum pressure ratio. In this study, the compressed air at the exit of centrifugal compressor was re-circulated and injected to the impeller inlet by using two injection nozzles in order to suppress the surge phenomenon. The most effective circumferential position was examined to reduce the flow rate at the surge inception. Moreover, the influences of the injection on the fluctuating property of the flow field before and after the surge inception were investigated by examining the frequency of static pressure fluctuation on the wall surface and visualizing the compressor wall surface by oil-film visualization technique.

Simulation Analysis of DC and Switching Impulse Superposition Circuit

NASA Astrophysics Data System (ADS)

Zhang, Chenmeng; Xie, Shijun; Zhang, Yu; Mao, Yuxiang

2018-03-01

Surge capacitors running between the natural bus and the ground are affected by DC and impulse superposition voltage during operation in the converter station. This paper analyses the simulation aging circuit of surge capacitors by PSCAD electromagnetic transient simulation software. This paper also analyses the effect of the DC voltage to the waveform of the impulse voltage generation. The effect of coupling capacitor to the test voltage waveform is also studied. Testing results prove that the DC voltage has little effect on the waveform of the output of the surge voltage generator, and the value of the coupling capacitor has little effect on the voltage waveform of the sample. Simulation results show that surge capacitor DC and impulse superimposed aging test is feasible.

Sputtering, Surging Sun [HD Video

NASA Image and Video Library

2017-12-08

STEREO (Ahead) caught the action as one edge of a single active region spurted out more than a dozen surges of plasma in less than two days (Feb. 15-16, 2010). As seen in extreme UV light, the surges were narrow and directional outbursts driven by intense magnetic activity in the active region. While these kinds of outbursts have been observed numerous times, it was the frequency of so many surges in a short span of time that caught our attention. In this wavelength of UV light we are seeing singly ionized Helium at about 60,000 degrees C. For more information: stereo.gsfc.nasa.gov/ Credit: NASA/GSFC/STEREO To learn more about NASA's Sun Earth Day go here: sunearthday.nasa.gov/2010/index.php

Attenuation correction factors for cylindrical, disc and box geometry

NASA Astrophysics Data System (ADS)

Agarwal, Chhavi; Poi, Sanhita; Mhatre, Amol; Goswami, A.; Gathibandhe, M.

2009-08-01

In the present study, attenuation correction factors have been experimentally determined for samples having cylindrical, disc and box geometry and compared with the attenuation correction factors calculated by Hybrid Monte Carlo (HMC) method [ C. Agarwal, S. Poi, A. Goswami, M. Gathibandhe, R.A. Agrawal, Nucl. Instr. and. Meth. A 597 (2008) 198] and with the near-field and far-field formulations available in literature. It has been observed that the near-field formulae, although said to be applicable at close sample-detector geometry, does not work at very close sample-detector configuration. The advantage of the HMC method is that it is found to be valid for all sample-detector geometries.

Attenuation Factors for B(E2) in the Microscopic Description of Multiphonon States ---A Simple Model Analysis---

NASA Astrophysics Data System (ADS)

Matsuyanagi, K.

1982-05-01

With an exactly solvable O(4) model of Piepenbring, Silvestre-Brac and Szymanski, we demonstrate that the attenuation factor for the B(E2) values, derived by the lowest-order approximation of the multiphonon method, takes excellent care of the kinematical anharmonicity effects, if multiphonon states are defined in the intrinsic subspace orthogonal to the pairing rotation. It is also shown that the other attenuation effect characterizing the interacting boson model is not a dominant effect in the model analysed here.

Assessing extreme sea levels due to tropical cyclones in the Atlantic basin

NASA Astrophysics Data System (ADS)

Muis, Sanne; Lin, Ning; Verlaan, Martin; Winsemius, Hessel; Vatvani, Deepak; Ward, Philip; Aerts, Jeroen

2017-04-01

Tropical cyclones (TCs), including hurricanes and typhoons, are characterised by high wind speeds and low pressure and cause dangerous storm surges in coastal areas. Over the last 50 years, storm surge incidents in the Atlantic accounted for more than 1,000 deaths in the United Stated. Recent flooding disasters, such as Hurricane Katrina in New Orleans in 2005 and, Hurricane Sandy in New York in 2012, exemplify the significant TC surge risk in the United States. In this contribution, we build on Muis et al. (2016), and present a new modelling framework to simulate TC storm surges and estimate their probabilities for the Atlantic basin. In our framework we simulate the surge levels by forcing the Global Tide and Surge Model (GTSM) with wind and pressure fields from TC events. To test the method, we apply it to historical storms that occurred between 1988 and 2015 in the Atlantic Basin. We obtain high-resolution meteorological forcing by applying a parametric hurricane model (Holland 1980; Lin and Chavas 2012) to the TC extended track data set (Demuth et al. 2006; updated), which describes the position, intensity and size of the historical TCs. Preliminary results show that this framework is capable of accurately reproducing the main surge characteristics during past events, including Sandy and Katrina. While the resolution of GTSM is limited for local areas with a complex bathymetry, the overall performance of the model is satisfactory for the basin-scale application. For an accurate assessment of risk to coastal flooding in the Atlantic basin it is essential to provide reliable estimates of surge probabilities. However, the length of observed TC tracks is too short to accurately estimate the probabilities of extreme TC events. So next steps are to statistically extend the observed record to many thousands of years (e.g., Emanuel et al. 2006), in order to force GTSM with a large number of synthetic storms. Based on these synthetic simulations, we would be able to provide reliable probabilities of surge levels for the entire Atlantic basin. References Demuth, J., DeMaria, M., and Knaff, J.A. (2006). Improvement of advanced microwave sounder unit tropical cyclone intensity and size estimation algorithms. Journal of Applied Meteorology., 45, pp. 1573-1581. Emanuel, K., Ravela, S., Vivant, E. and Risi, C. (2006). A statistical deterministic approach to hurricane risk assessment. Bulletin of the American Meteorological Society, 87(3), pp.299-314. Holland, G.J. (1980). An analytic model of the wind and pressure profiles in hurricanes. Monthly Weather Review, 108(8), pp.1212-1218. Lin, N. and D. Chavas (2012). On hurricane parametric wind and applications in storm surge modeling. Journal of Geophysical Research - Atmospheres. 117. doi:10.1029/2011jd017126. Muis, S., Verlaan, M., Winsemius, H. C., Aerts, J. C. J. H., & Ward, P. J. (2016). A global reanalysis of storm surge and extreme sea levels. Nature Communications, 7(7:11969), 1-11.

Employing high resolution satellite imagery to document a rapid glacier surge in the Karakoram - risks and opportunities for hazard assessment

NASA Astrophysics Data System (ADS)

Steiner, J. F.; Kraaijenbrink, P. D. A.; Jiduc, S. G.; Immerzeel, W. W.

2017-12-01

Glacier surges occur regularly in the Karakoram but their driving mechanisms, recurrence and its relation to climatic change remain unclear. Since many glacier tongues in the region reach to very low elevations, local populations are often exposed to glacial hazards. While the scientific interpretation of hazard is one challenge, adequately communicating results to possibly affected stakeholders poses a different set of hurdles. Using DEMs as well as Landsat imagery in combination with high-resolution Planet imagery we quantify surface elevation changes and flow velocities to document a glacier surge of the Khurdopin glacier, located in a remote valley in Pakistan, in the first half of 2017. Results reveal that an accumulation of ice mass leads to a rapid surge in peaking with velocities above 5000 m a-1 or 0.5 m h-1 during a few days. Velocities increase steadily during a four-year build-up phase prior to the actual surge, while the remaining 15 years of the recurring cycle the glacier is quiescent. It is hypothesized that the surge is mainly initiated as a result of increased pressure melting caused by ice accumulation. However, surface observations show increased crevassing and disappearance of supra glacial ponds, which could have led to increased lubrication of the glacier bed. As a consequence of the surging tongue blocking the main valley a lake has formed and grown continuously in size over two months at a rate of up to 3000 m2 per day. Using satellite imagery with a frequent overpass rate we are able to (a) characterize the nature of glacier surges in the region with greater detail and (b) monitor the surge as well as the formation of the lake as it develops. Having developed a connection to local stakeholders we were able to provide rapid hazard assessments to affected communities, which can be employed to define possible actions. We show the potential of satellite imagery - freely available Landsat in combination with commercial Planet imagery -, which in combination with a scientific evaluation of the data can be employed to provide (a) immediate hazard assessments in remote mountainous regions and (b) to raise local awareness about these risks and provide pathways for local stakeholders to assess future hazard potentials.

Effect of the Camelid’s Seminal Plasma Ovulation-Inducing Factor/β-NGF: A Kisspeptin Target Hypothesis

PubMed Central

El Allali, Khalid; El Bousmaki, Najlae; Ainani, Hassan; Simonneaux, Valérie

2017-01-01

Female mammals are classified into spontaneous and induced ovulators based on the mechanism eliciting ovulation. Ovulation in spontaneous species (e.g., human, sheep, cattle, horse, pigs, and most rodents) occurs at regular intervals and depends upon the circulating estradiol. However, in induced ovulators (e.g., rabbits, ferrets, cats, and camelids), ovulation is associated with coitus. In the later, various factors have been proposed to trigger ovulation, including auditory, visual, olfactory, and mechanic stimuli. However, other studies have identified a biochemical component in the semen of induced ovulators responsible for the induction of ovulation and named accordingly ovulation-inducing factor (OIF). In camelids, intramuscular or intrauterine administration of seminal plasma (SP) was shown to induce the preovulatory luteinizing hormone (LH) surge followed by ovulation and subsequent formation of corpus luteum. Recently, this OIF has been identified from SP as a neurotrophin, the β subunit of nerve growth factor (β-NGF). β-NGF is well known as promoting neuron survival and growth, but in this case, it appears to induce ovulation through an endocrine mode of action. Indeed, β-NGF may be absorbed through the endometrium to be conveyed, via the blood stream, to the central structures regulating the LH preovulatory surge. In this review, we provide a summary of the most relevant results obtained in the field, and we propose a working hypothesis for the central action of β-NGF based on our recent demonstration of the presence of neurons expressing kisspeptin, a potent stimulator of GnRH/LH, in the camel hypothalamus. PMID:28713816

Effect of the Camelid's Seminal Plasma Ovulation-Inducing Factor/β-NGF: A Kisspeptin Target Hypothesis.

PubMed

El Allali, Khalid; El Bousmaki, Najlae; Ainani, Hassan; Simonneaux, Valérie

2017-01-01

Female mammals are classified into spontaneous and induced ovulators based on the mechanism eliciting ovulation. Ovulation in spontaneous species (e.g., human, sheep, cattle, horse, pigs, and most rodents) occurs at regular intervals and depends upon the circulating estradiol. However, in induced ovulators (e.g., rabbits, ferrets, cats, and camelids), ovulation is associated with coitus. In the later, various factors have been proposed to trigger ovulation, including auditory, visual, olfactory, and mechanic stimuli. However, other studies have identified a biochemical component in the semen of induced ovulators responsible for the induction of ovulation and named accordingly ovulation-inducing factor (OIF). In camelids, intramuscular or intrauterine administration of seminal plasma (SP) was shown to induce the preovulatory luteinizing hormone (LH) surge followed by ovulation and subsequent formation of corpus luteum. Recently, this OIF has been identified from SP as a neurotrophin, the β subunit of nerve growth factor (β-NGF). β-NGF is well known as promoting neuron survival and growth, but in this case, it appears to induce ovulation through an endocrine mode of action. Indeed, β-NGF may be absorbed through the endometrium to be conveyed, via the blood stream, to the central structures regulating the LH preovulatory surge. In this review, we provide a summary of the most relevant results obtained in the field, and we propose a working hypothesis for the central action of β-NGF based on our recent demonstration of the presence of neurons expressing kisspeptin, a potent stimulator of GnRH/LH, in the camel hypothalamus.

INHIBITION OF PAN NEUROTROPHIN RECEPTOR P75 ATTENUATES DIESEL PARTICULATE-INDUCED ENHANCEMENT OF ALLERGIC AIRWAY RESPONSES IN C57/BL6J MICE

EPA Science Inventory

Recent investigations have linked neurotrophins including nerve growth factor (NGF), neurotrophin-3 (NT-3), and brain-derived neurotrophic factor (BDNF) to allergic airways diseases. Antibody blockade of NGF attenuates airway resistance in allergic mice. Diesel exhaust particle...

Tropical Cyclone Storm Surge Inundation and Velocity Hazard Mapping of the State of Andhra Pradesh (India) using ADCIRC

NASA Astrophysics Data System (ADS)

Brackins, J. T.; Kalyanapu, A. J.

2017-12-01

The Northern Indian Ocean Bay of Bengal region, including parts of India, Bangladesh, Myanmar, and Sri Lanka, is the largest bay in the world and is structured in such a manner as to produce the world's largest tropical cyclone (TC) storm surges (SS), with approximately five surge events greater than 5 meters in magnitude each decade. (Needham et al. 2015). Although some studies have been performed to attempt to capture the magnitude and location of historical surges (Shaji et al. 2014) and to model surges in the immediate sense, there is a notable lack of application to the effects on coastal infrastructure in these areas. Given that these areas are some of the most densely populated and least economically able to prepare and recover, it is important to consider the potential effects of storm surge to discover areas where improvements can be made with the limited resources available to these areas. To this end, an ADvanced-CIRCulation (ADCIRC) model (Luettich and Westerink 2004) was created for the Bay of Bengal, using the General Bathymetric Chart of the Oceans (GEBCO 2014) as bathymetric and topographic data, and a combination of the Joint Typhoon Warning Center (JTWC) and India Meteorological Department (IMD) records for storm tracks. For the state of Andhra Pradesh, several major TC events ranging from 1977 to 2014 were selected to be modeled with the goal of creating hazard maps of storm surge inundation and velocity for the state. These hazard maps would be used to identify high-vulnerability areas with the goal of implementing land-use planning and coastal development practices that will aid in ameliorating both the loss of life and economic damages sustained as a result of these TCs.

Estimating Areas of Vulnerability: Sea Level Rise and Storm Surge Hazards in the National Parks

NASA Astrophysics Data System (ADS)

Caffrey, M.; Beavers, R. L.; Slayton, I. A.

2013-12-01

The University of Colorado Boulder in collaboration with the National Park Service has undertaken the task of compiling sea level change and storm surge data for 105 coastal parks. The aim of our research is to highlight areas of the park system that are at increased risk of rapid inundation as well as periodic flooding due to sea level rise and storms. This research will assist park managers and planners in adapting to climate change. The National Park Service incorporates climate change data into many of their planning documents and is willing to implement innovative coastal adaptation strategies. Events such as Hurricane Sandy highlight how impacts of coastal hazards will continue to challenge management of natural and cultural resources and infrastructure along our coastlines. This poster will discuss the current status of this project. We discuss the impacts of Hurricane Sandy as well as the latest sea level rise and storm surge modeling being employed in this project. In addition to evaluating various drivers of relative sea-level change, we discuss how park planners and managers also need to consider projected storm surge values added to sea-level rise magnitudes, which could further complicate the management of coastal lands. Storm surges occurring at coastal parks will continue to change the land and seascapes of these areas, with the potential to completely submerge them. The likelihood of increased storm intensity added to increasing rates of sea-level rise make predicting the reach of future storm surges essential for planning and adaptation purposes. The National Park Service plays a leading role in developing innovative strategies for coastal parks to adapt to sea-level rise and storm surge, whilst coastal storms are opportunities to apply highly focused responses.

Properties of the Central American cold surge

NASA Technical Reports Server (NTRS)

Mcguirk, James P.; Reding, Philip J.; Zhang, Yuxia

1993-01-01

The Central American cold surge (CACS) is a frontal incursion from the United States into Central America and resembles the East Asian cold surge. They occur more frequently than analyzed by NMC or by published results, based on our observations between 1979 and 1990. Climatology and structure are quantified, based on surface and upper air stations throughout Central America and satellite products from GOES visible and infrared sensors and SSM/I precipitable water and rain rate sensors.

Anomalous Surge of the White-Light Corona at the Onset of the Declining Phase of Solar Cycle 24

NASA Astrophysics Data System (ADS)

Lamy, P.; Boclet, B.; Wojak, J.; Vibert, D.

2017-04-01

In late 2014, when the current Solar Cycle 24 entered its declining phase, the white-light corona as observed by the LASCO-C2 coronagraph underwent an unexpected surge that increased its global radiance by 60%, reaching a peak value comparable to the peak values of the more active Solar Cycle 23. A comparison of the temporal variation of the white-light corona with the variations of several indices and proxies of solar activity indicate that it best matches the variation of the total magnetic field. The daily variations point to a localized enhancement or bulge in the electron density that persisted for several months. Carrington maps of the radiance and of the HMI photospheric field allow connecting this bulge to the emergence of the large sunspot complex AR 12192 in October 2014, the largest since AR 6368 observed in November 1990. The resulting unusually high increase of the magnetic field and the distortion of the neutral sheet in a characteristic inverse S-shape caused the coronal plasma to be trapped along a similar pattern. A 3D reconstruction of the electron density based on time-dependent solar rotational tomography supplemented by 2D inversion of the coronal radiance confirms the morphology of the bulge and reveals that its level was well above the standard models of a corona of the maximum type, by typically a factor of 3. A rather satisfactory agreement is found with the results of the thermodynamic MHD model produced by Predictive Sciences, although discrepancies are noted. The specific configuration of the magnetic field that led to the coronal surge resulted from the interplay of various factors prevailing at the onset of the declining phase of the solar cycles, which was particularly efficient in the case of Solar Cycle 24.

Ethnic differences in the degree of morning blood pressure surge and in its determinants between Japanese and European hypertensive subjects: data from the ARTEMIS study.

PubMed

Hoshide, Satoshi; Kario, Kazuomi; de la Sierra, Alejandro; Bilo, Grzegorz; Schillaci, Giuseppe; Banegas, José Ramón; Gorostidi, Manuel; Segura, Julian; Lombardi, Carolina; Omboni, Stefano; Ruilope, Luis; Mancia, Giuseppe; Parati, Gianfranco

2015-10-01

Morning blood pressure (BP) surge has been reported to be a prognostic factor for cardiovascular events. Its determinants are still poorly defined, however. In particular, it is not clear whether ethnic differences play a role in determining morning surge (MS) size. Aim of our study was to explore whether differences exist in the size of MS between Japanese and Western European hypertensive patients. We included 2887 untreated hypertensive patients (age 62.3±8.8 years) from a European ambulatory BP monitoring database and 811 hypertensive patients from a Japanese database (Jichi Medical School Ambulatory Blood Pressure Monitoring WAVE1, age 72.3±9.8 years) following the same inclusion criteria. Their 24-hour ambulatory BP monitoring recordings were analyzed focusing on MS. Sleep-trough MS was defined as the difference between mean systolic BP during the 2 hours after awakening and mean systolic BP during the 1-hour night period that included the lowest sleep BP level. The sleep-trough MS was higher in Japanese than in European hypertensive patients after adjusting for age and 24-hour mean BP levels (40.1 [95% confidence interval 39.0-41.2] versus 23.0 [22.4-23.5] mm Hg; P<0.001). This difference remained significant after accounting for differences in night-time BP dipping. Age was independently associated with MS in the Japanese database, but not in the European subjects. Our results for the first time show the occurrence of substantial ethnic differences in the degree of MS. These findings may help in understanding the role of ethnic factors in cardiovascular risk assessment and in identifying possible ethnicity-related differences in the most effective measures to be implemented for prevention of BP-related cardiovascular events. © 2015 American Heart Association, Inc.

Simplified methods for real-time prediction of storm surge uncertainty: The city of Venice case study

NASA Astrophysics Data System (ADS)

Mel, Riccardo; Viero, Daniele Pietro; Carniello, Luca; Defina, Andrea; D'Alpaos, Luigi

2014-09-01

Providing reliable and accurate storm surge forecasts is important for a wide range of problems related to coastal environments. In order to adequately support decision-making processes, it also become increasingly important to be able to estimate the uncertainty associated with the storm surge forecast. The procedure commonly adopted to do this uses the results of a hydrodynamic model forced by a set of different meteorological forecasts; however, this approach requires a considerable, if not prohibitive, computational cost for real-time application. In the present paper we present two simplified methods for estimating the uncertainty affecting storm surge prediction with moderate computational effort. In the first approach we use a computationally fast, statistical tidal model instead of a hydrodynamic numerical model to estimate storm surge uncertainty. The second approach is based on the observation that the uncertainty in the sea level forecast mainly stems from the uncertainty affecting the meteorological fields; this has led to the idea to estimate forecast uncertainty via a linear combination of suitable meteorological variances, directly extracted from the meteorological fields. The proposed methods were applied to estimate the uncertainty in the storm surge forecast in the Venice Lagoon. The results clearly show that the uncertainty estimated through a linear combination of suitable meteorological variances nicely matches the one obtained using the deterministic approach and overcomes some intrinsic limitations in the use of a statistical tidal model.

Comparison of vacuum rise time, vacuum limit accuracy, and occlusion break surge of 3 new phacoemulsification systems.

PubMed

Han, Young Keun; Miller, Kevin M

2009-08-01

To compare vacuum rise time, vacuum limit accuracy, and occlusion break surge of 3 new phacoemulsification machines. Jules Stein Eye Institute and Department of Ophthalmology, David Geffen School of Medicine at UCLA, Los Angeles, California, USA. The vacuum rise time under normal and enhanced aspiration modes, vacuum limit accuracy, and occlusion break surge of the Infiniti Vision System, Stellaris Vision Enhancement System, and WhiteStar Signature Phacoemulsification System were tested. Vacuum rise time and limit accuracy were measured at limit settings of 400 mm Hg and 600 mm Hg. Surge area was recorded at vacuum limit settings of 200 mm Hg, 300 mm Hg, 400 mm Hg, and 500 mm Hg. The Infiniti had the fastest vacuum rise times under normal and enhanced aspiration modes. At 4 seconds, the vacuum limit accuracy was greatest with the Infiniti at the 400 mm Hg limit and the Signature at the 600 mm Hg limit. The Stellaris did not reach either vacuum target. The Infiniti performed better than the other 2 machines during testing of occlusion break surge at all vacuum limit settings above 200 mm Hg. Under controlled laboratory test conditions, the Infiniti had the fastest vacuum rise time, greatest vacuum limit accuracy at 400 mm Hg, and least occlusion break surge. These results can be explained by the lower compliance of the Infiniti system.

Volume-based characterization of postocclusion surge.

PubMed

Zacharias, Jaime; Zacharias, Sergio

2005-10-01

To propose an alternative method to characterize postocclusion surge using a collapsible artificial anterior chamber to replace the currently used rigid anterior chamber model. Fundación Oftamológica Los Andes, Santiago, Chile. The distal end of a phacoemulsification handpiece was placed inside a compliant artificial anterior chamber. Digital recordings of chamber pressure, chamber volume, inflow, and outflow were performed during occlusion break of the phacoemulsification tip. The occlusion break profile of 2 different consoles was compared. Occlusion break while using a rigid anterior chamber model produced a simultaneous increase of chamber inflow and outflow. In the rigid chamber model, pressure decreased sharply, reaching negative pressure values. Alternatively, with the collapsible chamber model, a delay was observed in the inflow that occurs to compensate the outflow surge. Also, the chamber pressure drop was smaller in magnitude, never undershooting below atmospheric pressure into negative values. Using 500 mm Hg as vacuum limit, the Infiniti System (Alcon) performed better that the Legacy (Alcon), showing an 18% reduction in peak volume variation. The collapsible anterior chamber model provides a more realistic representation of the postocclusion surge events that occur in the real eye during cataract surgery. Peak volume fluctuation (mL), half volume recovery time(s), and volume fluctuation integral value (mL x s) are proposed as realistic indicators to characterize the postocclusion surge performance. These indicators show that the Infiniti System has a better postocclusion surge behavior than the Legacy System.

Changes in the Earth's largest surge glacier system from satellite and airborne altimetry and imagery

NASA Astrophysics Data System (ADS)

Trantow, T.; Herzfeld, U. C.

2015-12-01

The Bering-Bagley Glacier System (BBGS), Alaska, one of the largest ice systems outside of Greenland and Antarctica, has recently surged (2011-2013), providing a rare opportunity to study the surge phenomenon in a large and complex system. Understanding fast-flowing glaciers and accelerations in ice flow, of which surging is one type, is critical to understanding changes in the cryosphere and ultimately changes in sea level. It is important to distinguish between types of accelerations and their consequences, especially between reversible or quasi-cyclic and irreversible forms of glacial acceleration, but current icesheet models treat all accelerating ice identically. Additionally, the surge provides an exceptional opportunity to study the influence of surface roughness and water content on return signals of altimeter systems. In this presentation, we analyze radar and laser altimeter data from CryoSat-2, NASA's Operation IceBridge (OIB), the ICESat Geoscience Laser Altimeter System (GLAS), ICESat-2's predecessor the Multiple Altimeter Beam Experimental Lidar (MABEL), and airborne laser altimeter and imagery campaigns by our research group. These measurements are used to study elevation, elevation change and crevassing throughout the glacier system. Analysis of the imagery from our airborne campaigns provides comprehensive characterizations of the BBGS surface over the course of the surge. Results from the data analysis are compared to numerical modeling experiments.

Pseudo-spectral control of a novel oscillating surge wave energy converter in regular waves for power optimization including load reduction

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tom, Nathan M.; Yu, Yi -Hsiang; Wright, Alan D.

The aim of this study is to describe a procedure to maximize the power-to-load ratio of a novel wave energy converter (WEC) that combines an oscillating surge wave energy converter with variable structural components. The control of the power-take-off torque will be on a wave-to-wave timescale, whereas the structure will be controlled statically such that the geometry remains the same throughout the wave period. Linear hydrodynamic theory is used to calculate the upper and lower bounds for the time-averaged absorbed power and surge foundation loads while assuming that the WEC motion remains sinusoidal. Previous work using pseudo-spectral techniques to solvemore » the optimal control problem focused solely on maximizing absorbed energy. This work extends the optimal control problem to include a measure of the surge foundation force in the optimization. The objective function includes two competing terms that force the optimizer to maximize power capture while minimizing structural loads. A penalty weight was included with the surge foundation force that allows control of the optimizer performance based on whether emphasis should be placed on power absorption or load shedding. Results from pseudo-spectral optimal control indicate that a unit reduction in time-averaged power can be accompanied by a greater reduction in surge-foundation force.« less

Pseudo-spectral control of a novel oscillating surge wave energy converter in regular waves for power optimization including load reduction

DOE PAGES

Tom, Nathan M.; Yu, Yi -Hsiang; Wright, Alan D.; ...

2017-04-18

The aim of this study is to describe a procedure to maximize the power-to-load ratio of a novel wave energy converter (WEC) that combines an oscillating surge wave energy converter with variable structural components. The control of the power-take-off torque will be on a wave-to-wave timescale, whereas the structure will be controlled statically such that the geometry remains the same throughout the wave period. Linear hydrodynamic theory is used to calculate the upper and lower bounds for the time-averaged absorbed power and surge foundation loads while assuming that the WEC motion remains sinusoidal. Previous work using pseudo-spectral techniques to solvemore » the optimal control problem focused solely on maximizing absorbed energy. This work extends the optimal control problem to include a measure of the surge foundation force in the optimization. The objective function includes two competing terms that force the optimizer to maximize power capture while minimizing structural loads. A penalty weight was included with the surge foundation force that allows control of the optimizer performance based on whether emphasis should be placed on power absorption or load shedding. Results from pseudo-spectral optimal control indicate that a unit reduction in time-averaged power can be accompanied by a greater reduction in surge-foundation force.« less

Human Resources for Treating HIV/AIDS: Are the Preventive Effects of Antiretroviral Treatment a Game Changer?

PubMed

Bärnighausen, Till; Bloom, David E; Humair, Salal

2016-01-01

Shortages of human resources for treating HIV/AIDS (HRHA) are a fundamental barrier to reaching universal antiretroviral treatment (ART) coverage in developing countries. Previous studies suggest that recruiting HRHA to attain universal ART coverage poses an insurmountable challenge as ART significantly increases survival among HIV-infected individuals. While new evidence about ART's prevention benefits suggests fewer infections may mitigate the challenge, new policies such as treatment-as-prevention (TasP) will exacerbate it. We develop a mathematical model to analytically study the net effects of these countervailing factors. Using South Africa as a case study, we find that contrary to previous results, universal ART coverage is achievable even with current HRHA numbers. However, larger health gains are possible through a surge-capacity policy that aggressively recruits HRHA to reach universal ART coverage quickly. Without such a policy, TasP roll-out can increase health losses by crowding out sicker patients from treatment, unless a surge capacity exclusively for TasP is also created.

Human Resources for Treating HIV/AIDS: Are the Preventive Effects of Antiretroviral Treatment a Game Changer?

PubMed Central

2016-01-01

Shortages of human resources for treating HIV/AIDS (HRHA) are a fundamental barrier to reaching universal antiretroviral treatment (ART) coverage in developing countries. Previous studies suggest that recruiting HRHA to attain universal ART coverage poses an insurmountable challenge as ART significantly increases survival among HIV-infected individuals. While new evidence about ART’s prevention benefits suggests fewer infections may mitigate the challenge, new policies such as treatment-as-prevention (TasP) will exacerbate it. We develop a mathematical model to analytically study the net effects of these countervailing factors. Using South Africa as a case study, we find that contrary to previous results, universal ART coverage is achievable even with current HRHA numbers. However, larger health gains are possible through a surge-capacity policy that aggressively recruits HRHA to reach universal ART coverage quickly. Without such a policy, TasP roll-out can increase health losses by crowding out sicker patients from treatment, unless a surge capacity exclusively for TasP is also created. PMID:27716813

A Pilot Study of Pedestrians with Visual Impairments Detecting Traffic Gaps and Surges Containing Hybrid Vehicles

PubMed Central

Emerson, Robert Wall; Naghshineh, Koorosh; Hapeman, Julie; Wiener, William

2010-01-01

The increasing number of hybrid and quiet internal combustion engine vehicles may impact the travel abilities of pedestrians who are blind. Pedestrians who rely on auditory cues for structuring their travel may face challenges in making crossing decisions in the presence of quiet vehicles. This article describes results of initial studies looking at the crossing decisions of pedestrians who are blind at an uncontrolled crossing (no traffic control) and a light controlled intersection. The presence of hybrid vehicles was a factor in each situation. At the uncontrolled crossing, Toyota hybrids were most difficult to detect but crossing decisions were made more often in small gaps ended by a Honda hybrid. These effects were seen only at speed under 20 mph. At the light controlled intersection, parallel surges of traffic were most difficult to detect when made up only of a Ford Escape hybrid. Results suggest that more controlled studies of vehicle characteristics impacting crossing decisions of pedestrians who are blind are warranted. PMID:21379367

A Pilot Study of Pedestrians with Visual Impairments Detecting Traffic Gaps and Surges Containing Hybrid Vehicles.

PubMed

Emerson, Robert Wall; Naghshineh, Koorosh; Hapeman, Julie; Wiener, William

2011-03-01

The increasing number of hybrid and quiet internal combustion engine vehicles may impact the travel abilities of pedestrians who are blind. Pedestrians who rely on auditory cues for structuring their travel may face challenges in making crossing decisions in the presence of quiet vehicles. This article describes results of initial studies looking at the crossing decisions of pedestrians who are blind at an uncontrolled crossing (no traffic control) and a light controlled intersection. The presence of hybrid vehicles was a factor in each situation. At the uncontrolled crossing, Toyota hybrids were most difficult to detect but crossing decisions were made more often in small gaps ended by a Honda hybrid. These effects were seen only at speed under 20 mph. At the light controlled intersection, parallel surges of traffic were most difficult to detect when made up only of a Ford Escape hybrid. Results suggest that more controlled studies of vehicle characteristics impacting crossing decisions of pedestrians who are blind are warranted.

World meat consumption patterns: An overview of the last fifty years (1961-2011).

PubMed

Sans, P; Combris, P

2015-11-01

Driven by economic development and urbanisation, protein consumption has surged worldwide over the last 50years, rising from 61g per person per day in 1961 to 80g per person per day in 2011 [Corrected]. This contribution analyses the apparent convergence of dietary models worldwide with respect to the proportion of ABP and especially meat in intake. By using FAO data for 183 countries over the period 1961-2011, the authors show the connection between annual per capita GDP and the level of ABP (R2=0.62) and meat consumption (R2=0.62). They emphasise the surge in ABP intake in emerging countries (China, Brazil) which has partly replaced plant protein. However, for similar degrees of economic development, the composition of ABPs and the position of meat within this category vary significantly among countries, suggesting that historical, geographical, cultural and religious factors may be involved. Copyright © 2015 Elsevier Ltd. All rights reserved.

Attenuation in gas-charged magma

NASA Astrophysics Data System (ADS)

Collier, L.; Neuberg, J. W.; Lensky, N.; Lyakhovsky, V.; Navon, O.

2006-05-01

Low frequency seismic events observed on volcanoes, such as Soufriere Hills Volcano, Montserrat, are thought to be caused by a resonating system. The modelling of seismic waves in gas-charged magma is critical for the understanding of seismic resonance effects in conduits, dykes and cracks. Seismic attenuation, which depends mainly on magma viscosity, gas and crystal content, is an essential factor in such modelling attempts. So far only two-phase gas-melt systems with the assumption of no diffusion and transport of volatiles between the melt and the gas bubbles have been considered. In this study, we develop a method of quantifying attenuation within gas-charged magma, including the effects of diffusion and exsolution of gas into the bubbles. The results show that by including such bubble growth processes attenuation levels are increased within magma. The resulting complex behaviour of attenuation with pressure and frequency indicates that two factors are controlling attenuation, the first due to viscous hindrance or the melt, and the second due diffusion processes. The level of attenuation within a gas-charged magma conduit suggests an upper limit on the length of a resonating conduit section of just a few hundred meters.

Scattering images from autocorrelation functions of P-wave seismic velocity images: the case of Tenerife Island (Canary Islands, Spain)

NASA Astrophysics Data System (ADS)

García-Yeguas, A.; Sánchez-Alzola, A.; De Siena, L.; Prudencio, J.; Díaz-Moreno, A.; Ibáñez, J. M.

2018-03-01

We present a P-wave scattering image of the volcanic structures under Tenerife Island using the autocorrelation functions of P-wave vertical velocity fluctuations. We have applied a cluster analysis to total quality factor attenuation ( {Q}_t^{-1} ) and scattering quality factor attenuation ( {Q}_{PSc}^{-1} ) images to interpret the structures in terms of intrinsic and scattering attenuation variations on a 2D plane, corresponding to a depth of 2000 m, and check the robustness of the scattering imaging. The results show that scattering patterns are similar to total attenuation patterns in the south of the island. There are two main areas where patterns differ: at Cañadas-Teide-Pico Viejo Complex, high total attenuation and average-to-low scattering values are observed. We interpret the difference as induced by intrinsic attenuation. In the Santiago Ridge Zone (SRZ) region, high scattering values correspond to average total attenuation. In our interpretation, the anomaly is induced by an extended scatterer, geometrically related to the surficial traces of Garachico and El Chinyero historical eruptions and the area of highest seismic activity during the 2004-2008 seismic crises.

Administration of a leptin antagonist during the neonatal leptin surge induces alterations in the redox and inflammatory state in peripubertal /adolescent rats.

PubMed

Mela, Virginia; Hernandez, Oskarina; Hunsche, Caroline; Diaz, Francisca; Chowen, Julie A; De la Fuente, Mónica

2017-10-15

The importance of the neonatal leptin surge in rodents in neurodevelopmental processes has aroused curiosity in its implication in other physiological systems. Given the role of leptin in neuro-immune interactions, we hypothesized that the neonatal leptin surge could have an effect on the oxidative and inflammatory stress situations of both systems. We blocked the neonatal leptin surge by a leptin antagonist and measured several parameters of oxidative and inflammatory stress in the spleen, hypothalamus and adipose tissue of peripubertal/adolescent rats. The treated rats showed lower activity of several antioxidant enzymes in the spleen and their leukocytes released lower levels of mitogen-stimulated IL-10 and IL-13 and higher levels of TNF-alpha. In conclusion, the neonatal leptin surge may have a key role in the establishment of adequate redox and inflammatory states in the immune system, which is important for the generation of adequate immune responses and to obtain and maintain good health. Copyright © 2017 Elsevier B.V. All rights reserved.

Increasing the highest storm surge in Busan harbor

NASA Astrophysics Data System (ADS)

Oh, Sang Myeong; Moon, Il-Ju; Kwon, Suk Jae

2017-04-01

One of the most pronounced effects of climate change in coastal regions is sea level rise and storm surges. Busan in particular, the fifth largest container handling port in the world, has suffered from serious storm surges and experienced a remarkable mean sea level (MSL) rise. This study investigates a long-term variation of annual maximum surge height (AMSH) using sea level data observed in Busan over 53 years (1962 2014). The decomposition of astronomical tides and surge components shows that the AMSH has increased 18 cm over 53 years (i.e., 3.5 mm/year), which is much larger than the MSL trend (2.5 mm/year) in Busan. This significant increase in AMSH is mostly explained by the increased intensity of landfall typhoons over the Korean peninsula (KP), which is associated with the increase of sea surface temperature and the decrease of vertical wind shear at mid-latitudes of the western North Pacific. In a projected future warming environment, the combination of an increasing MSL and AMSH will accelerate the occurrence of record-breaking extreme sea levels, which will be a potential threat in Busan harbor.

The United States and AfricaLooking Toward the Next Decade: Symposium Report

DTIC Science & Technology

2016-07-01

improve urban infrastructures and to tackle the unemployment issue. One factor complicating efforts to deal with the challenges of urbanization is...resources. They are producing many underqualified graduates. As a result, unemployment , and thereby frustration, among recent secondary school and...outside investment in Africa’s resource sectors , there has been a surge in both direct and portfolio investment in the consumer and services sectors of

Plasma Cytokines Following Thermal Injury and Their Relationship with Patient Mortality, Burn Size, and Time Postburn,

DTIC Science & Technology

1993-09-01

AND TIME POSTBURN Adriana C. Drost, MS, David G. Burleson, PhD, William G. Cioffi, Jr., MD, Bryan S. Jordan, RN, MS, Arthur D. Mason, Jr., MD, and...trauma. J 2, IL-6). Science 239-502,1i988 Surg Res 48:622, 1990 7. Garmnan RD, Jacobs KA , Clark SC, et al: B-cell-stimulatory factor 23. Hack CE, De Groot

Benchmarking the Integration of WAVEWATCH III Results into HAZUS-MH: Preliminary Results

NASA Technical Reports Server (NTRS)

Berglund, Judith; Holland, Donald; McKellip, Rodney; Sciaudone, Jeff; Vickery, Peter; Wang, Zhanxian; Ying, Ken

2005-01-01

The report summarizes the results from the preliminary benchmarking activities associated with the use of WAVEWATCH III (WW3) results in the HAZUS-MH MR1 flood module. Project partner Applied Research Associates (ARA) is integrating the WW3 model into HAZUS. The current version of HAZUS-MH predicts loss estimates from hurricane-related coastal flooding by using values of surge only. Using WW3, wave setup can be included with surge. Loss estimates resulting from the use of surge-only and surge-plus-wave-setup were compared. This benchmarking study is preliminary because the HAZUS-MH MR1 flood module was under development at the time of the study. In addition, WW3 is not scheduled to be fully integrated with HAZUS-MH and available for public release until 2008.

Passive seismic monitoring of the Bering Glacier during its last surge event

NASA Astrophysics Data System (ADS)

Zhan, Z.

2017-12-01

The physical causes behind glacier surges are still unclear. Numerous evidences suggest that they probably involve changes in glacier basal conditions, such as switch of basal water system from concentrated large tunnels to a distributed "layer" as "connected cavities". However, most remote sensing approaches can not penetrate to the base to monitor such changes continuously. Here we apply seismic interferometry using ambient noise to monitor glacier seismic structures, especially to detect possible signatures of the hypothesized high-pressure water "layer". As an example, we derive an 11-year long history of seismic structure of the Bering Glacier, Alaska, covering its latest surge event. We observe substantial drops of Rayleigh and Love wavespeeds across the glacier during the surge event, potentially caused by changes in crevasse density, glacier thickness, and basal conditions.

Storm surge modeling and applications in coastal areas

USGS Publications Warehouse

Dube, Shisir K.; Murty, Tad S.; Feyen, Jesse C.; Cabrera, Reggina; Harper, Bruce A.; Bales, Jerad D.; Amer, Saud A.

2010-01-01

This chapter introduces the reader to a wide spectrum of storm surge modeling systems used to assess the impact of tropical cyclones, covering a range of numerical methods, model domains, forcing and boundary conditions, and purposes. New technologies to obtain data such as deployment of temporary sensors and remote sensing practices to support modeling are also presented. Extensive storm surge modeling applications have been made with existing modeling systems and some of them are described in this chapter.The authors recognize the importance of evaluating river-ocean interactions in coastal environments during tropical cyclones. Therefore, the coupling of hydraulic (riverine) and storm surge models is discussed. In addition, results from studies performed in the coast of India are shown which generated maps to help emergency managers and reduce risk due to coastal inundation.

The simulation of Typhoon-induced coastal inundation in Busan, South Korea applying the downscaling technique

NASA Astrophysics Data System (ADS)

Jang, Dongmin; Park, Junghyun; Yuk, Jin-Hee; Joh, MinSu

2017-04-01

Due to typhoons, the south coastal cities including Busan in South Korea coastal are very vulnerable to a surge, wave and corresponding coastal inundation, and are affected every year. In 2016, South Korea suffered tremendous damage by typhoon 'Chaba', which was developed near east-north of Guam on Sep. 28 and had maximum 10-minute sustained wind speed of about 50 m/s, 1-minute sustained wind speed of 75 m/s and a minimum central pressure of 905 hpa. As 'Chaba', which is the strongest since typhoon 'Maemi' in 2003, hit South Korea on Oct. 5, it caused a massive economic and casualty damage to Ulsan, Gyeongju and Busan in South Korea. In particular, the damage of typhoon-induced coastal inundation in Busan, where many high-rise buildings and residential areas are concentrated near coast, was serious. The coastal inundation could be more affected by strong wind-induced wave than surge. In fact, it was observed that the surge height was about 1 m averagely and a significant wave height was about 8 m at coastal sea nearby Busan on Oct. 5 due to 'Chaba'. Even though the typhoon-induced surge elevated the sea level, the typhoon-induced long period wave with wave period of more than 15s could play more important role in the inundation. The present work simulated the coastal inundation induced by 'Chaba' in Busan, South Korea considering the effects of typhoon-induced surge and wave. For 'Chaba' hindcast, high resolution Weather Research and Forecasting model (WRF) was applied using a reanalysis data produced by NCEP (FNL 0.25 degree) on the boundary and initial conditions, and was validated by the observation of wind speed, direction and pressure. The typhoon-induced coastal inundation was simulated by an unstructured gird model, Finite Volume Community Ocean Model (FVCOM), which is fully current-wave coupled model. To simulate the wave-induced inundation, 1-way downscaling technique of multi domain was applied. Firstly, a mother's domain including Korean peninsula was simulated using wind and pressure produced by WRF to produce surge and wave. And then, the wave-induced inundation was simulated applying the surge height and wave height simulated by mother's model to the open boundary and initial condition of child's model which was ranged near Busan. Our simulated surge height is generally underestimated about 15 % due to the underestimation of surface pressure on WRF. However, since the effect of wave on inundation could be more significant than surge-induced forcing in this real system, our research could predict the typhoon-induced inundation by combining the surge and wave forcing in nested domain.

InSAR Observations and Finite Element Modeling of Crustal Deformation Around a Surging Glacier, Iceland

NASA Astrophysics Data System (ADS)

Spaans, K.; Auriac, A.; Sigmundsson, F.; Hooper, A. J.; Bjornsson, H.; Pálsson, F.; Pinel, V.; Feigl, K. L.

2014-12-01

Icelandic ice caps, covering ~11% of the country, are known to be surging glaciers. Such process implies an important local crustal subsidence due to the large ice mass being transported to the ice edge during the surge in a few months only. In 1993-1995, a glacial surge occurred at four neighboring outlet glaciers in the southwestern part of Vatnajökull ice cap, the largest ice cap in Iceland. We estimated that ~16±1 km3 of ice have been moved during this event while the fronts of some of the outlet glaciers advanced by ~1 km.Surface deformation associated with this surge has been surveyed using Interferometric Synthetic Aperture Radar (InSAR) acquisitions from 1992-2002, providing high resolution ground observations of the study area. The data show about 75 mm subsidence at the ice edge of the outlet glaciers following the transport of the large volume of ice during the surge (Fig. 1). The long time span covered by the InSAR images enabled us to remove ~12 mm/yr of uplift occurring in this area due to glacial isostatic adjustment from the retreat of Vatnajökull ice cap since the end of the Little Ice Age in Iceland. We then used finite element modeling to investigate the elastic Earth response to the surge, as well as confirm that no significant viscoelastic deformation occurred as a consequence of the surge. A statistical approach based on Bayes' rule was used to compare the models to the observations and obtain an estimate of the Young's modulus (E) and Poisson's ratio (v) in Iceland. The best-fitting models are those using a one-kilometer thick top layer with v=0.17 and E between 12.9-15.3 GPa underlain by a layer with v=0.25 and E from 67.3 to 81.9 GPa. Results demonstrate that InSAR data and finite element models can be used successfully to reproduce crustal deformation induced by ice mass variations at Icelandic ice caps.Fig. 1: Interferograms spanning 1993 July 31 to 1995 June 19, showing the surge at Tungnaárjökull (Tu.), Skaftárjökull (Sk.) and Síðujökull (Sí.) outlet glaciers. The black and grey arrows show the azimuth of the satellite and the look direction, respectively. (a) Wrapped interferogram showing the surge deformation (2π = 28.3 mm deformation). (b) Unwrapped interferogram with the black star as the reference area and negative values indicating line of sight lengthening (Auriac et al., 2014, doi:10.1093/gji/ggu205).

Contribution of biotic and abiotic factors in the natural attenuation of sulfamethoxazole: A path analysis approach.

PubMed

Li, Yan; Rashid, Azhar; Wang, Hongjie; Hu, Anyi; Lin, Lifeng; Yu, Chang-Ping; Chen, Meng; Sun, Qian

2018-08-15

Sulfamethoxazole (SMX) is a sulfonamide antibiotic, widely used as curative and preventive drug for human, animal, and aquaculture bacterial infections. Its residues have been ubiquitously detected in the surface waters and sediments. In the present study, SMX dissipation and kinetics was studied in the natural water samples from Jiulong River under simulated complex natural conditions as well as conditions to mimic various biotic and abiotic environmental conditions in isolation. Structural equation modeling (SEM) by employing partial least square technique in path coefficient analysis was used to investigate the direct and indirect contributions of different environmental factors in the natural attenuation of SMX. The model explained 81% of the variability in natural attenuation as a dependent variable under the influence of sole effects of direct photo-degradation, indirect photo-degradation, hydrolysis, microbial degradation and bacterial degradation. The results of SEM suggested that the direct and indirect photo-degradation were the major pathways in the SMX natural attenuation. However, other biotic and abiotic factors also play a mediatory role during the natural attenuation and other processes. Furthermore, the potential transformation products of SMX were identified and their toxicity was evaluated. Copyright © 2018 Elsevier B.V. All rights reserved.

Involvement of {gamma}-secretase in postnatal angiogenesis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hayashi, Hiroki; Nakagami, Hironori; Takami, Yoichi

2007-11-23

{gamma}-Secretase cleaves the transmembrane domains of several integral membrane proteins involved in vasculogenesis. Here, we investigated the role of {gamma}-secretase in the regulation of postnatal angiogenesis using {gamma}-secretase inhibitors (GSI). In endothelial cell (EC), {gamma}-secretase activity was up-regulated under hypoxia or the treatment of vascular endothelial growth factor (VEGF). The treatment of GSI significantly attenuated growth factor-induced EC proliferation and migration as well as c-fos promoter activity in a dose-dependent manner. In vascular smooth muscle cell (VSMC), treatment of GSI significantly attenuated growth factor-induced VEGF and fibroblast growth factor-2 (FGF-2) expression. Indeed, GSI attenuated VEGF-induced tube formation and inhibited FGF-2-inducedmore » angiogenesis on matrigel in mice as quantified by FITC-lectin staining of EC. Overall, we demonstrated that {gamma}-secretase may be key molecule in postnatal angiogenesis which may be downstream molecule of growth factor-induced growth and migration in EC, and regulate the expression of angiogenic growth factors in VSMC.« less

Updated Death and Injury Rates of U.S. Military Personnel During the Conflicts in Iraq and Afghanistan

DTIC Science & Technology

2014-12-01

rates.11 Not all of the changes in casualty rates over time were statistically significant. The hostile death rates during the surges in Iraq and...hostile- death rates in each theater and period). However, the declines during the post-surge periods in both theaters were overwhelmingly significant...the more-seriously wounded in Vietnam were less likely to survive. 7 Figure 6. Hostile Death Rates Before, During, and After the Surges in Iraq

Reconstruction Leaders’ Perceptions of the Commander’s Emergency Response Program in Iraq

DTIC Science & Technology

2012-04-30

provided immediate support to the Iraqi people. American Commanders in Iraq used CERP funds to build schools , roads, health clinics, sewers, and...and 2008 we considered them as having served during the surge. If their time in Iraq was before those years we considered them to be pre- surge. If...their time in Iraq was after those years we considered them as having served post-surge. More details about our survey methodology are in Appendix

Disaster metrics: quantitative benchmarking of hospital surge capacity in trauma-related multiple casualty events.

PubMed

Bayram, Jamil D; Zuabi, Shawki; Subbarao, Italo

2011-06-01

Hospital surge capacity in multiple casualty events (MCE) is the core of hospital medical response, and an integral part of the total medical capacity of the community affected. To date, however, there has been no consensus regarding the definition or quantification of hospital surge capacity. The first objective of this study was to quantitatively benchmark the various components of hospital surge capacity pertaining to the care of critically and moderately injured patients in trauma-related MCE. The second objective was to illustrate the applications of those quantitative parameters in local, regional, national, and international disaster planning; in the distribution of patients to various hospitals by prehospital medical services; and in the decision-making process for ambulance diversion. A 2-step approach was adopted in the methodology of this study. First, an extensive literature search was performed, followed by mathematical modeling. Quantitative studies on hospital surge capacity for trauma injuries were used as the framework for our model. The North Atlantic Treaty Organization triage categories (T1-T4) were used in the modeling process for simplicity purposes. Hospital Acute Care Surge Capacity (HACSC) was defined as the maximum number of critical (T1) and moderate (T2) casualties a hospital can adequately care for per hour, after recruiting all possible additional medical assets. HACSC was modeled to be equal to the number of emergency department beds (#EDB), divided by the emergency department time (EDT); HACSC = #EDB/EDT. In trauma-related MCE, the EDT was quantitatively benchmarked to be 2.5 (hours). Because most of the critical and moderate casualties arrive at hospitals within a 6-hour period requiring admission (by definition), the hospital bed surge capacity must match the HACSC at 6 hours to ensure coordinated care, and it was mathematically benchmarked to be 18% of the staffed hospital bed capacity. Defining and quantitatively benchmarking the different components of hospital surge capacity is vital to hospital preparedness in MCE. Prospective studies of our mathematical model are needed to verify its applicability, generalizability, and validity.

A stochastic storm surge generator for the German North Sea and the multivariate statistical assessment of the simulation results

NASA Astrophysics Data System (ADS)

Wahl, Thomas; Jensen, Jürgen; Mudersbach, Christoph

2010-05-01

Storm surges along the German North Sea coastline led to major damages in the past and the risk of inundation is expected to increase in the course of an ongoing climate change. The knowledge of the characteristics of possible storm surges is essential for the performance of integrated risk analyses, e.g. based on the source-pathway-receptor concept. The latter includes the storm surge simulation/analyses (source), modelling of dike/dune breach scenarios (pathway) and the quantification of potential losses (receptor). In subproject 1b of the German joint research project XtremRisK (www.xtremrisk.de), a stochastic storm surge generator for the south-eastern North Sea area is developed. The input data for the multivariate model are high resolution sea level observations from tide gauges during extreme events. Based on 25 parameters (19 sea level parameters and 6 time parameters) observed storm surge hydrographs consisting of three tides are parameterised. Followed by the adaption of common parametric probability distributions and a large number of Monte-Carlo-Simulations, the final reconstruction leads to a set of 100.000 (default) synthetic storm surge events with a one-minute resolution. Such a data set can potentially serve as the basis for a large number of applications. For risk analyses, storm surges with peak water levels exceeding the design water levels are of special interest. The occurrence probabilities of the simulated extreme events are estimated based on multivariate statistics, considering the parameters "peak water level" and "fullness/intensity". In the past, most studies considered only the peak water levels during extreme events, which might not be the most important parameter in any cases. Here, a 2D-Archimedian copula model is used for the estimation of the joint probabilities of the selected parameters, accounting for the structures of dependence overlooking the margins. In coordination with subproject 1a, the results will be used as the input for the XtremRisK subprojects 2 to 4. The project is funded by the German Federal Ministry of Education and Research (BMBF) (Project No. 03 F 0483 B).

Strategic Engagement of Technical Surge Capacity for Intensified Polio Eradication Initiative in Nigeria, 2012-2015.

PubMed

Yehualashet, Yared G; Mkanda, Pascal; Gasasira, Alex; Erbeto, Tesfaye; Onimisi, Anthony; Horton, Janet; Banda, Richard; Tegegn, Sisay G; Ahmed, Haruna; Afolabi, Oluwole; Wadda, Alieu; Vaz, Rui G; Nsubuga, Peter

2016-05-01

Following the 65th World Health Assembly (WHA) resolution on intensification of the Global Poliomyelitis Eradication Initiative (GPEI), the Nigerian government, with support from the World Health Organization (WHO) and other partners, implemented a number of innovative strategies to curb the transmission of wild poliovirus (WPV) in the country. One of the innovations successfully implemented since mid 2012 is the WHO's engagement of surge capacity personnel. The WHO reorganized its functional structure, adopted a transparent recruitment and deployment process, provided focused technical and management training, and applied systematic accountability framework to successfully manage the surge capacity project in close collaboration with the national counterparts and partners. The deployment of the surge capacity personnel was guided by operational and technical requirement analysis. Over 2200 personnel were engaged, of whom 92% were strategically deployed in 11 states classified as high risk on the basis of epidemiological risk analysis and compromised security. These additional personnel were directly engaged in efforts aimed at improving the performance of polio surveillance, vaccination campaigns, increased routine immunization outreach sessions, and strengthening partnership with key stakeholders at the operational level, including community-based organizations. Programmatic interventions were sustained in states in which security was compromised and the risk of polio was high, partly owing to the presence of the surge capacity personnel, who are engaged from the local community. Since mid-2012, significant programmatic progress was registered in the areas of polio supplementary immunization activities, acute flaccid paralysis surveillance, and routine immunization with the support of the surge capacity personnel. As of 19 June 2015, the last case of WPV was reported on 24 July 2014. The surge infrastructure has also been instrumental in building local capacity; supporting other public health emergencies, such as the Ebola outbreak response and measles and meningitis outbreaks; and strengthening the integrated disease surveillance and response. Due to weak health systems in the country, it is vital to maintain a reasonable level of the surge capacity for successful implementation of the 2013-2018 global polio endgame strategy and beyond. © 2016 World Health Organization; licensee Oxford Journals.

Strategic Engagement of Technical Surge Capacity for Intensified Polio Eradication Initiative in Nigeria, 2012–2015

PubMed Central

Yehualashet, Yared G.; Mkanda, Pascal; Gasasira, Alex; Erbeto, Tesfaye; Onimisi, Anthony; Horton, Janet; Banda, Richard; Tegegn, Sisay G.; Ahmed, Haruna; Afolabi, Oluwole; Wadda, Alieu; Vaz, Rui G.; Nsubuga, Peter

2016-01-01

Background. Following the 65th World Health Assembly (WHA) resolution on intensification of the Global Poliomyelitis Eradication Initiative (GPEI), the Nigerian government, with support from the World Health Organization (WHO) and other partners, implemented a number of innovative strategies to curb the transmission of wild poliovirus (WPV) in the country. One of the innovations successfully implemented since mid 2012 is the WHO's engagement of surge capacity personnel. Methods. The WHO reorganized its functional structure, adopted a transparent recruitment and deployment process, provided focused technical and management training, and applied systematic accountability framework to successfully manage the surge capacity project in close collaboration with the national counterparts and partners. The deployment of the surge capacity personnel was guided by operational and technical requirement analysis. Results. Over 2200 personnel were engaged, of whom 92% were strategically deployed in 11 states classified as high risk on the basis of epidemiological risk analysis and compromised security. These additional personnel were directly engaged in efforts aimed at improving the performance of polio surveillance, vaccination campaigns, increased routine immunization outreach sessions, and strengthening partnership with key stakeholders at the operational level, including community-based organizations. Discussion. Programmatic interventions were sustained in states in which security was compromised and the risk of polio was high, partly owing to the presence of the surge capacity personnel, who are engaged from the local community. Since mid-2012, significant programmatic progress was registered in the areas of polio supplementary immunization activities, acute flaccid paralysis surveillance, and routine immunization with the support of the surge capacity personnel. As of 19 June 2015, the last case of WPV was reported on 24 July 2014. The surge infrastructure has also been instrumental in building local capacity; supporting other public health emergencies, such as the Ebola outbreak response and measles and meningitis outbreaks; and strengthening the integrated disease surveillance and response. Due to weak health systems in the country, it is vital to maintain a reasonable level of the surge capacity for successful implementation of the 2013–2018 global polio endgame strategy and beyond. PMID:26912379

Active identification and control of aerodynamic instabilities in axial and centrifugal compressors

NASA Astrophysics Data System (ADS)

Krichene, Assad

In this thesis, it is experimentally shown that dynamic cursors to stall and surge exist in both axial and centrifugal compressors using the experimental axial and centrifugal compressor rigs located in the School of Aerospace Engineering at the Georgia Institute of Technology. Further, it is shown that the dynamic cursors to stall and surge can be identified in real-time and they can be used in a simple control scheme to avoid the occurrence of stall and surge instabilities altogether. For the centrifugal compressor, a previously developed real-time observer is used in order to detect dynamic cursors to surge in real-time. An off-line analysis using the Fast Fourier Transform (FFT) of the open loop experimental data from the centrifugal compressor rig is carried out to establish the influence of compressor speed on the dynamic cursor frequency. The variation of the amplitude of dynamic cursors with compressor operating condition from experimental data is qualitatively compared with simulation results obtained using a generic compression system model subjected to white noise excitation. Using off-line analysis results, a simple control scheme based on fuzzy logic is synthesized for surge avoidance and recovery. The control scheme is implemented in the centrifugal compressor rig using compressor bleed as well as fuel flow to the combustor. Closed loop experimental results are obtained to demonstrate the effectiveness of the controller for both surge avoidance and surge recovery. The existence of stall cursors in an axial compression system is established using the observer scheme from off-line analysis of an existing database of a commercial gas turbine engine. However, the observer scheme is found to be ineffective in detecting stall cursors in the experimental axial compressor rig in the School of Aerospace Engineering at the Georgia Institute of Technology. An alternate scheme based on the amplitude of pressure data content at the blade passage frequency obtained using a pressure sensor located (in the casing) over the blade row is developed and used in the axial compressor rig for stall and surge avoidance and recovery. (Abstract shortened by UMI.)

The Extravehicular Suit Impact Load Attenuation Study for Use in Astronaut Bone Fracture Prediction

NASA Technical Reports Server (NTRS)

Lewandowski, Beth E.; Gilkey, Kelly M.; Sulkowski, Christina M.; Samorezov, Sergey; Myers, Jerry G.

2011-01-01

The NASA Integrated Medical Model (IMM) assesses the risk, including likelihood and impact of occurrence, of all credible in-flight medical conditions. Fracture of the proximal femur is a traumatic injury that would likely result in loss of mission if it were to happen during spaceflight. The low gravity exposure causes decreases in bone mineral density which heightens the concern. Researchers at the NASA Glenn Research Center have quantified bone fracture probability during spaceflight with a probabilistic model. It was assumed that a pressurized extravehicular activity (EVA) suit would attenuate load during a fall, but no supporting data was available. The suit impact load attenuation study was performed to collect analogous data. METHODS: A pressurized EVA suit analog test bed was used to study how the offset, defined as the gap between the suit and the astronaut s body, impact load magnitude and suit operating pressure affects the attenuation of impact load. The attenuation data was incorporated into the probabilistic model of bone fracture as a function of these factors, replacing a load attenuation value based on commercial hip protectors. RESULTS: Load attenuation was more dependent on offset than on pressurization or load magnitude, especially at small offsets. Load attenuation factors for offsets between 0.1 - 1.5 cm were 0.69 +/- 0.15, 0.49 +/- 0.22 and 0.35 +/- 0.18 for mean impact forces of 4827, 6400 and 8467 N, respectively. Load attenuation factors for offsets of 2.8 - 5.3 cm were 0.93 +/- 0.2, 0.94 +/- 0.1 and 0.84 +/- 0.5, for the same mean impact forces. Reductions were observed in the 95th percentile confidence interval of the bone fracture probability predictions. CONCLUSIONS: The reduction in uncertainty and improved confidence in bone fracture predictions increased the fidelity and credibility of the fracture risk model and its benefit to mission design and operational decisions.

Effects of Attenuation of Gas Hydrate-bearing Sediments on Seismic Data: Example from Mallik, Northwest Territories, Canada

NASA Astrophysics Data System (ADS)

Bellefleur, G.; Riedel, M.; Brent, T.

2007-05-01

Wave attenuation is an important physical property of hydrate-bearing sediments that is rarely taken into account in site characterization with seismic data. We present a field example showing improved images of hydrate- bearing sediments on seismic data after compensation of attenuation effects. Compressional quality factors (Q) are estimated from zero-offset Vertical Seismic Profiling data acquired at Mallik, Northwest Territories, Canada. During the last 10 years, two internationally-partnered research drilling programs have intersected three major intervals of sub-permafrost gas hydrates at Mallik, and have successfully extracted core samples containing significant amount of gas hydrates. Individual gas hydrate intervals are up to 40m in thickness and are characterized by high in situ gas hydrate saturation, sometimes exceeding 80% of pore volume of unconsolidated clastic sediments having average porosities ranging from 25% to 40%. The Q-factors obtained from the VSP data demonstrate significant wave attenuation for permafrost and hydrate- bearing sediments. These results are in agreement with previous attenuation estimates from sonic logs and crosshole data at different frequency intervals. The Q-factors obtained from VSP data were used to compensate attenuation effects on surface 3D seismic data acquired over the Mallik gas hydrate research wells. Intervals of gas hydrate on surface seismic data are characterized by strong reflectivity and effects from attenuation are not perceptible from a simple visual inspection of the data. However, the application of an inverse Q-filter increases the resolution of the data and improves correlation with log data, particularly for the shallowest gas hydrate interval. Compensation of the attenuation effects of the permafrost likely explains most of the improvements for the shallow gas hydrate zone. Our results show that characterization of the Mallik gas hydrates with seismic data not corrected for attenuation would tend to overestimate thicknesses and lateral extent of hydrate-bearing strata and hence, the volume of hydrates in place.

Cyanidin-3-glucoside and its phenolic acid metabolites attenuate visible light-induced retinal degeneration in vivo via activation of Nrf2/HO-1 pathway and NF-κB suppression.

PubMed

Wang, Yong; Huo, Yazhen; Zhao, Liang; Lu, Feng; Wang, Ou; Yang, Xue; Ji, Baoping; Zhou, Feng

2016-07-01

Cyanidin-3-glucoside (C3G) is a major anthocyanin in berries and a potential nutritional supplement for preventing retinal degeneration. However, the protective mechanism of C3G and its metabolites, protocatechuic acid (PCA) and ferulic acid (FA), remain unclear. The molecular mechanisms of C3G and its metabolites against retinal photooxidative damage in vivo are investigated. Pigmented rabbits were orally administered C3G, PCA, and FA (0.11 mmol/kg/day) for 3 weeks. Electroretinography, histological analysis, and TUNEL assay showed that C3G and its metabolites attenuated retinal cell apoptosis. The expression of oxidative stress markers were upregulated after light exposure but attenuated by C3G and FA, which may be attributed to the elevated secretion and expression of heme oxygenase (HO-1) and nuclear factor erythroid-2 related factor 2 (Nrf2). C3G, PCA, and FA attenuated the secretion or expression of inflammation-related genes; FA suppressed nuclear factor kappa B (NF-κB) activation. The treatments attenuated the light-induced changes on certain apoptotic proteins and angiogenesis-related cytokines. C3G and FA reduced light-induced retinal oxidative stress by activating the Nrf2/HO-1 antioxidant pathway. FA attenuated the light-induced retinal inflammation by suppressing NF-κB activation. C3G and its metabolites attenuated the photooxidation-induced apoptosis and angiogenesis in the retina. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

An extravehicular suit impact load attenuation study to improve astronaut bone fracture prediction.

PubMed

Sulkowski, Christina M; Gilkey, Kelly M; Lewandowski, Beth E; Samorezov, Sergey; Myers, Jerry G

2011-04-01

Understanding the contributions to the risk of bone fracture during spaceflight is essential for mission success. A pressurized extravehicular activity (EVA) suit analogue test bed was developed, impact load attenuation data were obtained, and the load at the hip of an astronaut who falls to the side during an EVA was characterized. Offset (representing the gap between the EVA suit and the astronaut's body), impact load magnitude, and EVA suit operating pressure were factors varied in the study. The attenuation data were incorporated into a probabilistic model of bone fracture risk during spaceflight, replacing the previous load attenuation value that was based on commercial hip protector data. Load attenuation was more dependent on offset than on pressurization or load magnitude, especially at small offset values. Load attenuation factors for offsets between 0.1-1.5 cm were 0.69 +/- 0.15, 0.49 +/- 0.22, and 0.35 +/- 0.18 for mean impact forces of 4827, 6400, and 8467 N, respectively. Load attenuation factors for offsets of 2.8-5.3 cm were 0.93 +/- 0.2, 0.94 +/- 0.1, and 0.84 +/- 0.5 for the same mean impact forces. The mean and 95th percentile bone fracture risk index predictions were each reduced by 65-83%. The mean and 95th percentile bone fracture probability predictions were both reduced approximately 20-50%. The reduction in uncertainty and improved confidence in bone fracture predictions increased the fidelity and credibility of the fracture risk model and its benefit to mission design and in-flight operational decisions.

Experiment evaluation of impact attenuator for a racing car under static load

NASA Astrophysics Data System (ADS)

Imanullah, Fahmi; Ubaidillah, Prasojo, Arfi Singgih; Wirawan, Adhe Aji

2018-02-01

The automotive world is a world where one of the factors that must be considered carefully is the safety aspect. In the formula student car one of the safety factor in the form of impact attenuator. Impact attenuator is used as anchoring when a collision occurs in front of the vehicle. In the rule of formula society of automotive engineer (FSAE) student, impact attenuator is required to absorb the energy must meet or exceed 7350 Joules with a slowdown in speed not exceeding 20 g average and peak of 40 g. The student formula participants are challenged to pass the boundaries so that in designing and making the impact attenuator must pay attention to the strength and use of the minimum material so that it can minimize the expenditure. In this work, an impact attenuator was fabricated and tested using static compression. The primary goal was evaluating the actual capability of the impact attenuator for impact energy absorption. The prototype was made of aluminum alloy in a prismatic shape, and the inside wall was filled with rooftop plastic slices and polyurethane hard foam. The compression test has successfully carried out, and the load versus displacement data could be used in calculating energy absorption capability. The result of the absorbent energy of the selected impact attenuator material. Impact attenuator full polyurethane absorbed energy reach 6380 Joule. For impact attenuator with aluminum polyurethane with a slashed rooftop material as section absorbed energy reach 6600 Joule. Impact attenuator with Aluminum Polyurethane with aluminum orange peel partitions absorbed energy reach 8800 Joule. From standard student formula, energy absorbed in this event must meet or exceed 7350 Joules that meet aluminum polyurethane with aluminum orange peel partitions with the ability to absorb 8800 Joule.

Outcome of Dupuytren Contractures After Collagenase Clostridium Histolyticum Injection: A Single-institution Experience.

PubMed

Hwee, Yin Kan; Park, Daniel; Vinas, Marisa; Litts, Christopher; Friedman, David

2017-08-01

Collagenase clostridium histolyticum (CCH) injection is an alternative to surgery for patients with Dupuytren disease (DD) of the metacarpophalangeal (MCP) and proximal interphalangeal (PIP) joints. The success of surgical and nonsurgical treatment modalities for DD is reported to vary widely between 25% and 80% (J Bone Joint Surg Am. 1985;67:1439-1443; Plast Reconstr Surg. 2007;120:44e-54e; J Bone Joint Surg Am. 2007;89:189-198; J Hand Surg Am. 2011:36:936-942; J Hand Surg Am. 1990;15:755-761; J Hand Surg Br. 1996;21:797-800; J Bone Joint Surg Br. 2000;82:90-94; Plast Reconstr Surg. 2005;115:802-810; Ann Plast Surg. 2006;57:13-17). This study presents the outcomes of patients with DD contractures treated with CCH injections at a single institution. An institutional review board-approved retrospective study was conducted of patients with DD of the hand treated with CCH injections in a single institution from February 2010 to April 2015. All patients received the recommended dose of 0.58 mg of CCH and returned for joint manipulation the following day. Data for follow-up at 7 and 30 days postoperatively and up to 5 years for patients who returned seeking further therapy for recurrent symptoms were reviewed. One hundred thirteen patients with a total of 146 affected joints (72 MCP; 74 PIP) were treated with CCH injections (95 males; 18 females; age, 40-92 y). Successful CCH therapy occurred in 75% of injected joints (109/146 joints; 59 MCP; 50 PIP), as defined by less than 5 degrees of contracture after treatment. Twenty-three percent of treated joints had partial correction (34/146 joints; 13 MCP; 21 PIP), as defined by between 5 and 30 degrees of residual contracture after treatment. Three patients (2%) had a failure of treatment, as defined by unchanged or worsened contracture from pretreatment baseline measurements. Fifteen patients (13%) returned to the clinic seeking additional therapy for recurrent joint contracture symptoms in 17 joints over a span of 1.5 months to 4 years after initial successful or partially successful treatment (17/143, 12%; 5 MCP; 12 PIP). Recurrence was defined as patients who sought treatment for a return of symptoms or greater than 20 degrees contracture in the setting of a palpable cord after initial full or partial contracture correction. Our 5-year outcome of CCH injections for DD contractures revealed full correction in 75% and partial correction in 23% of treated joints, with failure of treatment seen in only 2% of patients. Thirteen percent of the patients returned for additional treatment because of symptoms resulting from contracture recurrence in 12% of initially corrected or partially corrected joints. These positive outcomes are comparable with current surgical treatment modalities (J Hand Surg Am. 1990;15:755-761; J Bone Joint Surg Am. 1962;44B:602-613; J Clin Epidemiol. 2000;53:291-296). The use of CCH injections is an important nonsurgical treatment alternative for DD contractures of the MCP and PIP joints.

An investigation of the use of transmission ultrasound to measure acoustic attenuation changes in thermal therapy.

PubMed

Parmar, Neeta; Kolios, Michael C

2006-07-01

The potential of using a commercial ultrasound transmission imaging system to quantitatively monitor tissue attenuation changes after thermal therapy was investigated. The ultrasound transmission imaging system used, the AcoustoCam (Imperium Inc., MD) allows ultrasonic images to be captured using principles similar to that of a CCD-type camera that collects light. Ultrasound energy is focused onto a piezoelectric array by an acoustic lens system, creating a gray scale acoustic image. In this work, the pixel values from the acoustic images were assigned acoustic attenuation values by imaging polyacrylamide phantoms of varying known attenuation. After the calibration procedure, data from heated polyacrylamide/bovine serum albumin (BSA) based tissue-mimicking (TM) phantoms and porcine livers were acquired. Samples were heated in water at temperatures of 35, 45, 55, 65, and 75 degrees C for 1 h. Regions of interest were chosen in the images and acoustic attenuation values before and after heating were compared. An increase in ultrasound attenuation was found in phantoms containing BSA and in porcine liver. In the presence of BSA, attenuation in the TM phantom increased by a factor of 1.5, while without BSA no significant changes were observed. The attenuation of the porcine liver increased by up to a factor of 2.4, consistent with previously reported studies. The study demonstrates the feasibility of using a quantitative ultrasound transmission imaging system for monitoring thermal therapy.

Impact of hurricanes storm surges on the groundwater resources

USGS Publications Warehouse

Van Biersel, T. P.; Carlson, D.A.; Milner, L.R.

2007-01-01

Ocean surges onto coastal lowlands caused by tropical and extra tropical storms, tsunamis, and sea level rise affect all coastal lowlands and present a threat to drinking water resources of many coastal residents. In 2005, two such storms, Hurricanes Katrina and Rita struck the Gulf Coast of the US. Since September 2005, water samples have been collected from water wells impacted by the hurricanes' storm surges along the north shore of Lake Pontchartrain in southeastern Louisiana. The private and public water wells tested were submerged by 0.6-4.5 m of surging saltwater for several hours. The wells' casing and/or the associated plumbing were severely damaged. Water samples were collected to determine if storm surge water inundated the well casing and, if so, its effect on water quality within the shallow aquifers of the Southern Hills Aquifer System. In addition, the samples were used to determine if the impact on water quality may have long-term implication for public health. Laboratory testing for several indicator parameters (Ca/Mg, Cl/Si, chloride, boron, specific conductance and bacteria) indicates that surge water entered water wells' casing and the screened aquifer. Analysis of the groundwater shows a decrease in the Ca/Mg ratio right after the storm and then a return toward pre-Katrina values. Chloride concentrations were elevated right after Katrina and Rita, and then decreased downward toward pre-Katrina values. From September 2005 to June 2006, the wells showed improvement in all the saltwater intrusion indicators. ?? 2007 Springer-Verlag.

The Surge, Wave, and Tide Hydrodynamics (SWaTH) network of the U.S. Geological Survey—Past and future implementation of storm-response monitoring, data collection, and data delivery

USGS Publications Warehouse

Verdi, Richard J.; Lotspeich, R. Russell; Robbins, Jeanne C.; Busciolano, Ronald J.; Mullaney, John R.; Massey, Andrew J.; Banks, William S.; Roland, Mark A.; Jenter, Harry L.; Peppler, Marie C.; Suro, Thomas P.; Schubert, Christopher E.; Nardi, Mark R.

2017-06-20

After Hurricane Sandy made landfall along the northeastern Atlantic coast of the United States on October 29, 2012, the U.S. Geological Survey (USGS) carried out scientific investigations to assist with protecting coastal communities and resources from future flooding. The work included development and implementation of the Surge, Wave, and Tide Hydrodynamics (SWaTH) network consisting of more than 900 monitoring stations. The SWaTH network was designed to greatly improve the collection and timely dissemination of information related to storm surge and coastal flooding. The network provides a significant enhancement to USGS data-collection capabilities in the region impacted by Hurricane Sandy and represents a new strategy for observing and monitoring coastal storms, which should result in improved understanding, prediction, and warning of storm-surge impacts and lead to more resilient coastal communities.As innovative as it is, SWaTH evolved from previous USGS efforts to collect storm-surge data needed by others to improve storm-surge modeling, warning, and mitigation. This report discusses the development and implementation of the SWaTH network, and some of the regional stories associated with the landfall of Hurricane Sandy, as well as some previous events that informed the SWaTH development effort. Additional discussions on the mechanics of inundation and how the USGS is working with partners to help protect coastal communities from future storm impacts are also included.

Adriatic storm surges and related cross-basin sea-level slope

NASA Astrophysics Data System (ADS)

Međugorac, Iva; Orlić, Mirko; Janeković, Ivica; Pasarić, Zoran; Pasarić, Miroslava

2018-05-01

Storm surges pose a severe threat to the northernmost cities of the Adriatic coast, with Venice being most prone to flooding. It has been noted that some flooding episodes cause significantly different effects along the eastern and western Adriatic coasts, with indications that the difference is related to cross-basin sea-level slope. The present study aims to determine specific atmospheric conditions under which the slope develops and to explore connection with increased sea level along the two coastlines. The analysis is based on sea-level time series recorded at Venice and Bakar over the 1984-2014 interval, from which 38 most intensive storm-surge episodes were selected, and their meteorological backgrounds (ERA-Interim) were studied. The obtained sea-level extremes were grouped into three categories according to their cross-basin sea-level slope: storm surges that slope strongly westward (W type), those that slope eastward (E type) and ordinary storm surges (O type). Results show that the slope is controlled by wind action only, specifically, by the wind component towards a particular coast and by the cross-basin shear of along-basin wind. Meteorological fields were used to force an oceanographic numerical model in order to confirm the empirically established connection between the atmospheric forcing and the slope. Finally, it has been found that the intensity of storm surges along a particular Adriatic coast is determined by an interplay of sea-level slopes in the along and cross-basin directions.

Blind, olfactory bulbectomized female rats do not have daily luteinizing hormone surges.

PubMed

Pieper, D R; Mortiere, M R

1985-03-15

Previous studies from other laboratories have shown that female hamsters on short photoperiod become acyclic and have daily LH surges. These effects are eliminated if the animals are pinealectomized (PX) before being placed on the short photoperiod. Reiter and colleagues have shown that pre-pubertally blinded (BL) and olfactory bulbectomized (BX) female rats also have irregular estrous cycles, and this effect is also eliminated by PX [Endocr. Rev., 1 (1983) 109]. The main question addressed by the present study was whether the BL + BX rats also have daily LH surges. Twenty-five-day-old female Sprague-Dawley rats were divided into 5 groups: LD 14:10 sham (control); BL + BX; BL + BX + PX; LD 6:18 sham; and LD 6:18 BX. Ten weeks following surgery, all animals were sampled (0.5 ml) every 5 h for 2 days from an indwelling atrial catheter. Daily vaginal smears indicated that the BL + BX group were in estrus much less frequently than controls (15.8 +/- 1.8 vs 27.3 +/- 1.5% of days cornified cells, 10 rats/group smeared for more than 23 days each) and in general had longer, irregular cycles. The other 3 groups all had smear patterns similar to controls. All 5 groups had LH surges on the day of proestrus (greater than 200 ng/ml maximum value), but no group had LH surges on 2 sequential days or an LH surge on any other day of the cycle.(ABSTRACT TRUNCATED AT 250 WORDS)

Radar and optical mapping of surge persistence and marsh dieback along the New Jersey Mid-Atlantic coast after Hurricane Sandy

USGS Publications Warehouse

Rangoonwala, Amina; Enwright, Nicholas M.; Ramsey, Elijah W.; Spruce, Joseph P.

2016-01-01

This study combined a radar-based time series of Hurricane Sandy surge and estimated persistence with optical sensor-based marsh condition change to assess potential causal linkages of surge persistence and marsh condition change along the New Jersey Atlantic Ocean coast. Results based on processed TerraSAR-X and COSMO-SkyMed synthetic aperture radar (SAR) images indicated that surge flooding persisted for 12 h past landfall in marshes from Great Bay to Great Egg Harbor Bay and up to 59 h after landfall in many back-barrier lagoon marshes. Marsh condition change (i.e. loss of green marsh vegetation) was assessed from optical satellite images (Satellite Pour l’Observation de la Terre and Moderate Resolution Imaging Spectroradiometer) collected before and after Hurricane Sandy. High change in condition often showed spatial correspondence, with high surge persistence in marsh surrounding the lagoon portion of Great Bay, while in contrast, low change and high persistence spatial correspondence dominated the interior marshes of the Great Bay and Great Egg Harbor Bay estuaries. Salinity measurements suggest that these areas were influenced by freshwater discharges after landfall possibly mitigating damage. Back-barrier marshes outside these regions exhibited mixed correspondences. In some cases, topographic features supporting longer surge persistence suggested that non-correspondence between radar and optical data-based results may be due to differential resilience; however, in many cases, reference information was lacking to determine a reason for non-correspondence.

Rapid wave and storm surge warning system for tropical cyclones in Mexico

NASA Astrophysics Data System (ADS)

Appendini, C. M.; Rosengaus, M.; Meza, R.; Camacho, V.

2015-12-01

The National Hurricane Center (NHC) in Miami, is responsible for the forecast of tropical cyclones in the North Atlantic and Eastern North Pacific basins. As such, Mexico, Central America and Caribbean countries depend on the information issued by the NHC related to the characteristics of a particular tropical cyclone and associated watch and warning areas. Despite waves and storm surge are important hazards for marine operations and coastal dwellings, their forecast is not part of the NHC responsibilities. This work presents a rapid wave and storm surge warning system based on 3100 synthetic tropical cyclones doing landfall in Mexico. Hydrodynamic and wave models were driven by the synthetic events to create a robust database composed of maximum envelops of wind speed, significant wave height and storm surge for each event. The results were incorporated into a forecast system that uses the NHC advisory to locate the synthetic events passing inside specified radiuses for the present and forecast position of the real event. Using limited computer resources, the system displays the information meeting the search criteria, and the forecaster can select specific events to generate the desired hazard map (i.e. wind, waves, and storm surge) based on the maximum envelop maps. This system was developed in a limited time frame to be operational in 2015 by the National Hurricane and Severe Storms Unit of the Mexican National Weather Service, and represents a pilot project for other countries in the region not covered by detailed storm surge and waves forecasts.

Sensitivity study on durability variables of marine concrete structures

NASA Astrophysics Data System (ADS)

Zhou, Xin'gang; Li, Kefei

2013-06-01

In order to study the influence of parameters on durability of marine concrete structures, the parameter's sensitivity analysis was studied in this paper. With the Fick's 2nd law of diffusion and the deterministic sensitivity analysis method (DSA), the sensitivity factors of apparent surface chloride content, apparent chloride diffusion coefficient and its time dependent attenuation factor were analyzed. The results of the analysis show that the impact of design variables on concrete durability was different. The values of sensitivity factor of chloride diffusion coefficient and its time dependent attenuation factor were higher than others. Relative less error in chloride diffusion coefficient and its time dependent attenuation coefficient induces a bigger error in concrete durability design and life prediction. According to probability sensitivity analysis (PSA), the influence of mean value and variance of concrete durability design variables on the durability failure probability was studied. The results of the study provide quantitative measures of the importance of concrete durability design and life prediction variables. It was concluded that the chloride diffusion coefficient and its time dependent attenuation factor have more influence on the reliability of marine concrete structural durability. In durability design and life prediction of marine concrete structures, it was very important to reduce the measure and statistic error of durability design variables.

Retroreflective systems for remote readout

DOEpatents

Deason, V.A.; Colwell, F.S.; Ricks, K.L.

1998-10-13

A sensing device is described for sensing an environmental factor. The device includes a retroreflective layer disposed in a parallel, facing relationship with a sensing layer. The sensing layer has an initial optical absorption capacity for (1) sensing a presence of an environmental factor, (2) experiencing a change in optical absorption capacity responsive to said environmental factor, and (3) transmitting and attenuating light. A first portion of the sensing layer is sealed off from exposure to the environment while a second portion remains exposed to the environment such that, when the environmental factor is present, the first portion of the sensing layer is prevented from experiencing a change in optical absorption capacity responsive to said environmental factor. Well-collimated light beams are passed through the sensing layer and are reflected back from the retroreflective layer for processing. When the environmental factor is present, the beams which pass through the second portion are attenuated responsive to an increase in optical absorption capacity and are compared with the non-attenuated beams passing through the first portion to calculate the presence and quantity of the environmental factor. 7 figs.

Retroreflective systems for remote readout

DOEpatents

Deason, Vance A.; Colwell, Frederick S.; Ricks, Kirk L.

1998-01-01

A sensing device for sensing an environmental factor. The device includes a retroreflective layer disposed in a parallel, facing relationship with a sensing layer. The sensing layer has an initial optical absorption capacity for (i) sensing a presence of an environmental factor, (ii) experiencing a change in optical absorption capacity responsive to said environmental factor, and (iii) transmitting and attenuating light. A first portion of the sensing layer is sealed off from exposure to the environment while a second portion remains exposed to the environment such that, when the environmental factor is present, the first portion of the sensing layer is prevented from experiencing a change in optical absorption capacity responsive to said environmental factor. Well-collimated light beams are passed through the sensing layer and are reflected back from the retroreflective layer for processing. When the environmental factor is present, the beams which pass through the second portion are attenuated responsive to an increase in optical absorption capacity and are compared with the non-attenuated beams passing through the first portion to calculate the presence and quantity of the environmental factor.

Electrodynamic parameters in the nighttime sector during auroral substorms

NASA Technical Reports Server (NTRS)

Fujii, R.; Hoffman, R. A.; Anderson, P. C.; Craven, J. D.; Sugiura, M.; Frank, L. A.; Maynard, N. C.

1994-01-01

The characteristics of the large-scale electrodynamic parameters, field-aligned currents (FACs), electric fields, and electron precipitation, which are associated with auroral substorm events in the nighttime sector, have been obtained through a unique analysis which places the ionospheric measurements of these parameters into the context of a generic substorm determined from global auroral images. A generic bulge-type auroral emission region has been deduced from auroral images taken by the Dynamics Explorer 1 (DE 1) satellite during a number of isolated substorms, and the form has been divided into six sectors, based on the peculiar emission characteristics in each sector: west of bulge, surge horn, surge, middle surge, eastern bulge, and east of bulge. By comparing the location of passes of the Dynamics Explorer 2 (DE 2) satellite to the simultaneously obtained auroral images, each pass is placed onto the generic aurora. The organization of DE 2 data in this way has systematically clarified peculiar characteristics in the electrodynamic parameters. An upward net current mainly appears in the surge, with little net current in the surge horn and the west of bulge. The downward net current is distributed over wide longitudinal regions from the eastern bulge to the east of bulge. Near the poleward boundary of the expanding auroral bulge, a pair of oppositely directed FAC sheets is observed, with the downward FAC on the poleward side. This downward FAC and most of the upward FAC in the surge and the middle surge are assoc iated with narrow, intense antisunwqard convection, corresponding to an equatorward directed spikelike electric field. This pair of currents decreases in amplitude and latitudinal width toward dusk in the surge and the west of bulge, and the region 1 and 2 FACs become embedded in the sunward convection region. The upward FAC region associated with the spikelike field on the poleward edge of the bulge coincides well with intense electron precipitation and aurora appearing in this western and poleward protion of the bulge. The convection reversal is sharp in the west of bulge and surge horn sectors, and near the high-latitude boundary of the upward region 1, with a near stagnation region often extending over a large interval of latitude. In the eastern bulge and east of bulge sectors, the region 1 and 2 FACs are located in the sunward convection region, while a spikelike electric field occasionally appears poleward of the aurora but usually not associated with a pair of FAC sheets. In the eastern bulge, magnetic field data show complicated FAC distributions which correspond to current segments and filamentary currents.

Naval Procurement Problems: Theory and Practice

DTIC Science & Technology

1982-01-01

contrast when construction is contracted for the product may be modified before delivery and new information of relevance to both parties may be learned en...defense policy which may be desirable. For example, what price are we willing to pay for flexibility and surge capacity is a defense policy question...work force by an order of magnitude and achieve the productivity used as a basis for contract pricing was a primary factor in the schedule slippage

Injury Prevention and Performance Enhancement in 101st Airbourne Soldiers

DTIC Science & Technology

2012-02-01

those of elite athletes, with similar performance and nutrition needs. Dietary recommendations have been developed for the optimal amount of...2005. 33(3): p. 415-23. 10. Alonso AC, Greve JM, and Camanho GL: Evaluating the center of gravity of dislocations in soccer players with and without...Pietila T, and Werner S: Risk factors for leg injuries in female soccer players : a prospective investigation during one out-door season. Knee Surg

Surge of Hispar Glacier, Pakistan, between 2013 and 2017 detected from remote sensing observations

NASA Astrophysics Data System (ADS)

Rashid, Irfan; Abdullah, Tariq; Glasser, Neil F.; Naz, Heena; Romshoo, Shakil Ahmad

2018-02-01

This study analyses the behaviour of an actively surging glacier, Hispar, in Pakistan using remote sensing methods. We used 15 m panchromatic band of Landsat 8 OLI from 2013 to 2017 to assess the changes in glacier velocity, glacier geomorphology and supraglacial water bodies. For the velocity estimation, correlation image analysis (CIAS) was used, which is based on normalized cross-correlation (NCC) of satellite data. On-screen digitization was employed to quantify changes in the glacier geomorphology and dynamics of supraglacial water bodies on the glacier. Our velocity estimates indicate that the upper part of the glacier is presently undergoing an active surge which not only affects the debris distribution but also impacts the development of supraglacial water bodies. Velocities in the actively surging part of the main glacier trunk and its three tributaries reach up to 900 m yr- 1. The surge of Hispar also impacts the distribution of supraglacial debris causing folding of the medial moraines features present on the glacier surface. Changes in the number and size of supraglacial lakes and ponds were also observed during the observation period from 2013 to 2017.

High resolution climate projection of storm surge at the Venetian coast

NASA Astrophysics Data System (ADS)

Mel, R.; Sterl, A.; Lionello, P.

2013-04-01

Climate change impact on storm surge regime is of great importance for the safety and maintenance of Venice. In this study a future storm surge scenario is evaluated using new high resolution sea level pressure and wind data recently produced by EC-Earth, an Earth System Model based on the operational seasonal forecast system of the European Centre for Medium-Range Weather Forecasts (ECMWF). The study considers an ensemble of six 5 yr long simulations of the rcp45 scenario at 0.25° resolution and compares the 2094-2098 to the 2004-2008 period. EC-Earth sea level pressure and surface wind fields are used as input for a shallow water hydrodynamic model (HYPSE) which computes sea level and barotropic currents in the Adriatic Sea. Results show that a high resolution climate model is needed for producing realistic values of storm surge statistics and confirm previous studies in that they show little sensitivity of storm surge levels to climate change. However, some climate change signals are detected, such as increased persistence of high pressure conditions, an increased frequency of windless hour, and a decreased number of moderate windstorms.

Numerical simulation of MEMS-based blade load distribution control in centrifugal compressor surge suppression

NASA Astrophysics Data System (ADS)

Beneda, Károly

2012-11-01

The utilization of turbomachines requires up-to-date technologies to ensure safe operation throughout the widest possible range that makes novel ideas necessary to cope with classic problems. One of the most dangerous instability in compression systems is surge that has to be suppressed before its onset to avoid structural damages as well as other adverse consequences in the system. As surge occurs at low delivered mass flow rates the conventional widely spread surge control is based on bypassing the unnecessary airflow back to the atmosphere. This method has been implemented on a large number of aircraft and provides a robust control on suppressing compressor surge while creating a significant efficiency loss. This paper deals with an idea that has been originally designed as a fixed geometry that could be realized using up-to-date MEMS technology resulting in moderate losses but comparable stability enhancement. Previously the author has established the one-dimensional mathematical model of the concept, but it is indispensable - before the real instrument can be developed - to carry out detailed numerical simulation of the device. The aim of the paper is to acquaint the efforts of this CFD simulation.

An Investigation of Surge in a High-Speed Centrifugal Compressor Using Digital PIV

NASA Technical Reports Server (NTRS)

Wernet, Mark P.; Bright, Michelle M.; Skoch, Gary J.

2001-01-01

Compressor stall is a catastrophic breakdown of the flow in a compressor, which con lead to a loss of engine power, large pressure transients in the inlet/nacelle, and engine flameout. The implementation of active or passive strategies for controlling rotating stall and surge can significantly extend the stable operating range of a compressor without substantially sacrificing performance. It is crucial to identify the dynamic changes occurring in the flow field prior to rotating stall and surge in order to control these events successfully. Generally, pressure transducer measurements are made to capture the transient response of a compressor prior to rotating stall. In this investigation, Digital Particle Imaging Velocimetry (DPIV) is used in conjunction with dynamic pressure transducers to capture transient velocity and pressure measurements simultaneously in the nonstationary flow field during compressor surge. DPIV is an instantaneous, planar measurement technique that is ideally suited for studying transient flow phenomena in highspeed turbomachinery and has been used previously to map the stable operating point flow field in the diffuser of a high-speed centrifugal compressor. Through the acquisition of both DPIV images and transient pressure data, the time evolution of the unsteady flow during surge is revealed.

Specific Consideration on Superior Performance and Evaluation Methods of Polymer-housed Surge Arresters

NASA Astrophysics Data System (ADS)

Ishizaki, Yoshihiro; Kobayashi, Misao; Suzuki, Hironori; Futagami, Koichi

It is very suitable to select the polymer materials for the housings of surge arresters (SAs), because the polymer materials are generally soft and light weight. Therefore, many kinds of polymer-housed SAs using various polymer materials have been developed, and expanding into many countries. Considering these backgrounds, the JEC technical report (JEC-TR) 23002-2008; polymer-housed surge arrester(1) has been established based on the existent relevant standards of arresters, such as JEC-2371-2003; Insulator-housed surge arresters(2) and IEC 60099-4 Edition 2.2, Metal-oxide surge arresters (MOSAs) without gaps for a.c. systems(3) in order to introduce the technology and provide a common guide for testing of polymer-housed SAs. According as the JEC-TR, the various new applications of the polymer-housed SAs, which are caused by superior advantages such as compact, light weight, safe failure mode, anti-seismic performance, anti-pollution performance and cost efficiency design, have been realized recently in Japan. Therefore, this paper gives specific consideration on the superior performance of the polymer-housed SAs and the evaluation methods of the polymer-housed SAs, because there are some issues in the existent standards to be solved.

An Investigation of Surge in a High-Speed Centrifugal Compressor Using Digital PIV

NASA Technical Reports Server (NTRS)

Wernet, Mark P.; Bright, Michelle M.; Skoch, Gary J.

2002-01-01

Compressor stall is a catastrophic breakdown of the flow in a compressor, which can lead to a loss of engine power, large pressure transients in the inlet/nacelle and engine flameout. The implementation of active or passive strategies for controlling rotating stall and surge can significantly extend the stable operating range of a compressor without substantially sacrificing performance. It is crucial to identify the dynamic changes occurring in the flow field prior to rotating stall and surge in order to successfully control these events. Generally, pressure transducer measurements are made to capture the transient response of a compressor prior to rotating stall. In this investigation, Digital Particle Imaging Velocimetry (DPIV) is used in conjunction with dynamic pressure transducers to simultaneously capture transient velocity and pressure measurements in the non-stationary flow field during compressor surge. DPIV is an instantaneous, planar measurement technique which is ideally suited for studying transient flow phenomena in high speed turbomachinery and has been used previously to successfully map the stable operating point flow field in the diffuser of a high speed centrifugal compressor. Through the acquisition of both DPIV images and transient pressure data, the time evolution of the unsteady flow during surge is revealed.

Attenuated positive psychotic symptoms and social anxiety: Along a psychotic continuum or different constructs?

PubMed

Cooper, Shanna; Klugman, Joshua; Heimberg, Richard G; Anglin, Deidre M; Ellman, Lauren M

2016-01-30

Social anxiety commonly occurs across the course of schizophrenia, including in the premorbid and prodromal phases of psychotic disorders. Some have posited that social anxiety may exist on a continuum with paranoia; however, empirical data are lacking. The study aim was to determine whether attenuated positive psychotic symptoms are related to social anxiety. Young adults (N=1378) were administered the Prodromal Questionnaire (PQ), which measures attenuated positive psychotic symptoms (APPS), and the Social Phobia Scale (SPS), which measures a subset of social anxiety symptoms. Confirmatory factor analyses were conducted to address the extent to which social anxiety and APPS tap distinct dimensions. Confirmatory factor analyses support the existence of a separate social anxiety factor scale and four separate, though interrelated, APPS factor domains (unusual thought content, paranoia/suspiciousness, disorganized thinking, and perceptual abnormalities). Additionally, social anxiety was significantly, but not differently related to each APPS domain, although the magnitude was reduced between social anxiety and distressing APPS. The current study suggests that social anxiety and attenuated positive psychotic symptoms are separable constructs, but are significantly associated with each other. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

LCoE Analysis of Surge-Mode WEC

DOE Data Explorer

Bill Staby

2017-03-07

Spreadsheet which provides estimates of reductions in Levelized Cost of Energy for a surge-mode wave energy converter (WEC). This is made available via adoption of the advanced control strategies developed during this research effort.

Intake port

DOEpatents

Mendler, Edward Charles

2005-02-01

The volumetric efficiency and power of internal combustion engines is improved with an intake port having an intake nozzle, a venturi, and a surge chamber. The venturi is located almost halfway upstream the intake port between the intake valves and the intake plenum enabling the venturi throat diameter to be exceptionally small for providing an exceptionally high ram velocity and an exceptionally long and in turn high efficiency diffuser flowing into the surge chamber. The intake port includes an exceptionally large surge chamber volume for blow down of the intake air into the working cylinder of the engine.

Is Survival Time After Hemorrhage a Heritable, Quantitative Trait?: An Initial Assessment

DTIC Science & Technology

2008-06-01

The epidemiology of traumatic death. A population-based analysis. Arch Surg 128:571Y575, 1993. 5. Sauaia A, Moore FA, Moore EE, Moser KS, Brennan R...therapeutic goals and early warning of death. Arch Surg 106:630Y636, 1973. 752 SHOCK VOL. 29, NO. 6 KLEMCKE ET AL. Copyright @ 200 by the Shock...Hemorrhagic shock in rats. Measured blood volumes as the basis for the extent of hemorrhage. Arch Surg 99:484Y488, 1969. 19. Nose H, Morita M, Yawata T

The structure and energetics of midlatitude disturbances accompanying cold-air outbreaks over East Asia

NASA Technical Reports Server (NTRS)

Lau, N.-C.; Lau, K.-M.

1984-01-01

The evolution of extratropical transient waves as they propagate eastward from the Eurasian land mass toward the Pacific during selected cold surge events in the winter Monsoon Experiment (MONEX) is studied. The outstanding cold surge episodes during MONEX are first identified, and the salient synoptic features related to these events are described using composite streamline charts. The structure of rapidly varying disturbances accompanying the cold surges and the associated energetics are examined, and the behavior of those fluctuations over relatively longer time scales is addressed.

Complex patterns of glacier advances during the Lateglacial in the Chagan-Uzun Valley, Russian Altai

NASA Astrophysics Data System (ADS)

Gribenski, Natacha; Lukas, Sven; Jansson, Krister N.; Stroeven, Arjen P.; Preusser, Frank; Harbor, Jonathan M.; Blomdin, Robin; Ivanov, Mikhail N.; Heyman, Jakob; Petrakov, Dmitry; Rudoy, Alexei; Clifton, Tom; Lifton, Nathaniel A.; Caffee, Marc W.

2016-04-01

Over the last decades, numerous paleoglacial reconstructions have been carried out in Central Asian mountain ranges because glaciers in this region are sensitive to climate change, and thus their associated glacial deposits can be used as proxies for paleoclimate inference. However, non-climatic factors can complicate the relationship between glacier fluctuation and climate change. Careful investigations of the geomorphological and sedimentological context are therefore required to understand the mechanisms behind glacier retreat and expansion. In this study we present the first detailed paleoglacial reconstruction of the Chagan Uzun valley, located in the Russian Altai. This reconstruction is based on detailed geomorphological mapping, sedimentological logging, in situ cosmogenic 10Be and 26Al surface exposure dating of glacially transported boulders, and Optically Stimulated Luminescence (OSL) dating. The Chagan Uzun valley includes extensive lobate moraine belts (>100 km2) deposited in the intramontane Chuja basin, reflecting a series of pronounced former glacial advances. Observation of "hillside-scale" folding and extensive faulting of pre-existing soft sediments within the outer moraine belts, together with the geomorphology, indicate that these moraine belts were formed during glacier-surge like events. In contrast, the inner (up-valley) glacial landforms of the Chagan Uzun valley indicate that they were deposited by retreat of temperate valley glaciers and do not include features indicative of surging. Cosmogenic ages associated with the outermost, innermost and intermediary stages, all indicate deposition times clustered around 19.5 ka, although the 10Be ages of the outermost margin are likely slightly underestimated due to brief episode of glacial lake water coverage. Such close deposition timings are consistent with periods of fast or surge advances, followed by active glacier retreat. OSL dating yields significantly older ages of thick lacustrine accumulation along the Chagan Uzun River, which confirms the presence of lacustrine sediments in the Chagan Uzun glacier foreland before the glacier advances. Such sediments could have acted as a soft bed over which fast or unstable glacier flow occurred. This is the first study reporting surge-like behaviour of former glaciers in the Altai mountain range, supported by detailed geomorphological and sedimentological evidences. Such findings are crucial for paleoclimate inference, as the surge-related features cannot be attributed to a glacier system in equilibrium with the contemporary climate, and cannot be interpreted with traditional ELA reconstructions. This study also highlights the complexity of establishing robust paleoglacial chronologies in highly dynamic environments, with interactions between glacial events and the formation and drainage of lakes.

A combined field and numerical approach to understanding dilute pyroclastic density current dynamics and hazard potential: Auckland Volcanic Field, New Zealand

NASA Astrophysics Data System (ADS)

Brand, Brittany D.; Gravley, Darren M.; Clarke, Amanda B.; Lindsay, Jan M.; Bloomberg, Simon H.; Agustin-Flores, Javier; Németh, Károly

2014-04-01

The most dangerous and deadly hazards associated with phreatomagmatic eruptions in the Auckland Volcanic Field (AVF; Auckland, New Zealand) are those related to volcanic base surges - dilute, ground-hugging, particle laden currents with dynamic pressures capable of severe to complete structural damage. We use the well-exposed base surge deposits of the Maungataketake tuff ring (Manukau coast, Auckland), to reconstruct flow dynamics and destructive potential of base surges produced during the eruption. The initial base surge(s) snapped trees up to 0.5 m in diameter near their base as far as 0.7-0.9 km from the vent. Beyond this distance the trees were encapsulated and buried by the surge in growth position. Using the tree diameter and yield strength of the wood we calculate that dynamic pressures (Pdyn) in excess of 12-35 kPa are necessary to cause the observed damage. Next we develop a quantitative model for flow of and sedimentation from a radially-spreading, dilute pyroclastic density currents (PDCs) to determine the damage potential of the base surges produced during the early phases of the eruption and explore the implications of this potential on future eruptions in the region. We find that initial conditions with velocities on the order of 65 m s- 1, bulk density of 38 kg m- 3 and initial, near-vent current thicknesses of 60 m reproduce the field-based Pdyn estimates and runout distances. A sensitivity analysis revealed that lower initial bulk densities result in shorter run-out distances, more rapid deceleration of the current and lower dynamic pressures. Initial velocity does not have a strong influence on run-out distance, although higher initial velocity and slope slightly decrease runout distance due to higher rates of atmospheric entrainment. Using this model we determine that for base surges with runout distances of up to 4 km, complete destruction can be expected within 0.5 km from the vent, moderate destruction can be expected up to 2 km, but much less damage is expected up to the final runout distance of 4 km. For larger eruptions (base surge runout distance 4-6 km), Pdyn of > 35 kPa can be expected up to 2.5 km from source, ensuring complete destruction within this area. Moderate damage to reinforced structures and damage to weaker structures can be expected up to 6 km from source. In both cases hot ash may still cause damage due to igniting flammable materials in the distal-most regions of a base surge. This work illustrates our ability to combine field observations and numerical models to explore the depositional mechanisms, macroscale current dynamics, and potential impact of dilute PDCs. Thus, this approach may serve as a tool to understand the damage potential and extent of previous and potential future eruptions in the AVF.

Automating Flood Hazard Mapping Methods for Near Real-time Storm Surge Inundation and Vulnerability Assessment

NASA Astrophysics Data System (ADS)

Weigel, A. M.; Griffin, R.; Gallagher, D.

2015-12-01

Storm surge has enough destructive power to damage buildings and infrastructure, erode beaches, and threaten human life across large geographic areas, hence posing the greatest threat of all the hurricane hazards. The United States Gulf of Mexico has proven vulnerable to hurricanes as it has been hit by some of the most destructive hurricanes on record. With projected rises in sea level and increases in hurricane activity, there is a need to better understand the associated risks for disaster mitigation, preparedness, and response. GIS has become a critical tool in enhancing disaster planning, risk assessment, and emergency response by communicating spatial information through a multi-layer approach. However, there is a need for a near real-time method of identifying areas with a high risk of being impacted by storm surge. Research was conducted alongside Baron, a private industry weather enterprise, to facilitate automated modeling and visualization of storm surge inundation and vulnerability on a near real-time basis. This research successfully automated current flood hazard mapping techniques using a GIS framework written in a Python programming environment, and displayed resulting data through an Application Program Interface (API). Data used for this methodology included high resolution topography, NOAA Probabilistic Surge model outputs parsed from Rich Site Summary (RSS) feeds, and the NOAA Census tract level Social Vulnerability Index (SoVI). The development process required extensive data processing and management to provide high resolution visualizations of potential flooding and population vulnerability in a timely manner. The accuracy of the developed methodology was assessed using Hurricane Isaac as a case study, which through a USGS and NOAA partnership, contained ample data for statistical analysis. This research successfully created a fully automated, near real-time method for mapping high resolution storm surge inundation and vulnerability for the Gulf of Mexico, and improved the accuracy and resolution of the Probabilistic Storm Surge model.

National assessment of hurricane-induced coastal erosion hazards: Mid-Atlantic Coast

USGS Publications Warehouse

Doran, Kara S.; Stockdon, Hilary F.; Sopkin, Kristin L.; Thompson, David M.; Plant, Nathaniel G.

2013-01-01

Beaches serve as a natural buffer between the ocean and inland communities, ecosystems, and natural resources. However, these dynamic environments move and change in response to winds, waves, and currents. During extreme storms, changes to beaches can be large, and the results are sometimes catastrophic. Lives may be lost, communities destroyed, and millions of dollars spent on rebuilding. During storms, large waves may erode beaches, and high storm surge shifts the erosive force of the waves higher on the beach. In some cases, the combined effects of waves and surge may cause overwash (when waves and surge overtop the dune, transporting sand inland) or flooding. Building and infrastructure on or near a dune can be undermined during wave attack and subsequent erosion. During Hurricane Ivan in 2004, a five-story condominium in Orange Beach, Alabama, collapsed after the sand dune supporting the foundation eroded. Hurricane Sandy, which made landfall as an extra-tropical cyclone on October 29, 2012, caused erosion and undermining that destroyed roads, boardwalks, and foundations in Seaside Heights, New Jersey. Waves overtopping a dune can transport sand inland, covering roads and blocking evacuation routes or emergency relief. If storm surge inundates barrier island dunes, currents flowing across the island can create a breach, or a new inlet, completely severing evacuation routes. Waves and surge during Hurricane Sandy, which made landfall on October 29, 2012, left a breach that cut the road and bridge to Mantoloking, N.J. Extreme coastal changes caused by hurricanes may increase the vulnerability of communities both during a storm and to future storms. For example, when sand dunes on a barrier island are eroded substantially, inland structures are exposed to storm surge and waves. Absent or low dunes also allow water to flow inland across the island, potentially increasing storm surge in the back bay, on the soundside of the barrier, and on the mainland.

Seismic High Attenuation Beneath Southern New England Indicates High Asthenospheric Temperature and No Melt

NASA Astrophysics Data System (ADS)

Dong, M. T.; Menke, W. H.

2017-12-01

Seismic attenuation exhibits strong geographic variability in northeastern North America, with the highest values associated with the previously-recognized Northern Appalachian Anomaly (NAA) in southern New England. The shear wave quality factor at 100 km depth is 14s<25, the ratio of P-wave and S-wave quality factors is QP/Qs=1.2±0.03, and the frequency dependence parameter is α=0.39±0.025. The high values of Qp/Qs and α are compatible with laboratory measurements of unmelted rock and incompatible with widespread melting. The low Qs (high shear attenuation) implies high mantle temperatures ( 1550-1650°C) at 100 km depth (assuming no melt). Small-scale variations in attenuation suggests structural heterogeneity within the NAA, possibly due to lithospheric delamination caused by directional asthenospheric flow.

27. EXTENSION OF SURGE CHAMBER AND AIR PIPES TO PRESSURE ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

27. EXTENSION OF SURGE CHAMBER AND AIR PIPES TO PRESSURE LINE, HIGHLINE PUMPING PLANT. December 11, 1920 - Highline Canal & Pumping Station, South side of Salt River between Tempe, Phoenix & Mesa, Tempe, Maricopa County, AZ

Dynamics of sea level rise and coastal flooding on a changing landscape

NASA Astrophysics Data System (ADS)

Bilskie, M. V.; Hagen, S. C.; Medeiros, S. C.; Passeri, D. L.

2014-02-01

Standard approaches to determining the impacts of sea level rise (SLR) on storm surge flooding employ numerical models reflecting present conditions with modified sea states for a given SLR scenario. In this study, we advance this paradigm by adjusting the model framework so that it reflects not only a change in sea state but also variations to the landscape (morphologic changes and urbanization of coastal cities). We utilize a numerical model of the Mississippi and Alabama coast to simulate the response of hurricane storm surge to changes in sea level, land use/land cover, and land surface elevation for past (1960), present (2005), and future (2050) conditions. The results show that the storm surge response to SLR is dynamic and sensitive to changes in the landscape. We introduce a new modeling framework that includes modification of the landscape when producing storm surge models for future conditions.

Effect of Rotor- and Stator-Blade Modifications on Surge Performance of an 11-Stage Axial-Flow Compressor. I - Original Production Compressor of XJ40-WE-6 Engine

NASA Technical Reports Server (NTRS)

Finger, Harold B.; Essig, Robert H.; Conrad, E. William

1952-01-01

An investigation to increase the compressor surge-limit pressure ratio of the XJ40-WE-6 turbojet engine at high equivalent speeds was conducted at the NACA Lewis altitude wind tunnel. This report evaluates the compressor modifications which were restricted to (1) twisting rotor blades (in place) to change blade section angles and (2) inserting new stator diaphragms with different blade angles. Such configuration changes could be incorporated quickly and easily in existing engines at overhaul depots. It was found that slight improvements in the compressor surge limit were possible by compressor blade adjustment. However, some of the modifications also reduced the engine air flow and hence penalized the thrust. The use of a mixer assembly at the compressor outlet improved the surge limit with no appreciable thrust penalty.

A parabolic model of drag coefficient for storm surge simulation in the South China Sea

PubMed Central

Peng, Shiqiu; Li, Yineng

2015-01-01

Drag coefficient (Cd) is an essential metric in the calculation of momentum exchange over the air-sea interface and thus has large impacts on the simulation or forecast of the upper ocean state associated with sea surface winds such as storm surges. Generally, Cd is a function of wind speed. However, the exact relationship between Cd and wind speed is still in dispute, and the widely-used formula that is a linear function of wind speed in an ocean model could lead to large bias at high wind speed. Here we establish a parabolic model of Cd based on storm surge observations and simulation in the South China Sea (SCS) through a number of tropical cyclone cases. Simulation of storm surges for independent Tropical cyclones (TCs) cases indicates that the new parabolic model of Cd outperforms traditional linear models. PMID:26499262

Spatio-temporal variations in storm surges along the North Atlantic coasts

NASA Astrophysics Data System (ADS)

Marcos, Marta; Woodworth, Philip

2017-04-01

Extreme sea levels along the coasts of the North Atlantic Ocean and the Gulf of Mexico have been investigated using hourly tide gauge records compiled in the recently released GESLA-2 data set (www.gesla.org). These regions are among the most densely monitored coasts worldwide, with more than 300 high frequency quality-controlled tide gauge time series available. Here we estimate the storm surge component of extreme sea levels using both tidal residuals and skew surges, for which we explore the spatial and temporal coherency of their intensities, duration and frequency. We quantify the relationship of extremes with dominant large scale climate patterns and discuss the impact of mean sea level changes. Finally, we test the assumption of stationarity of the probability of extreme occurrence and to which extent it holds when mean sea level changes are considered in combination with storm surges.

A parabolic model of drag coefficient for storm surge simulation in the South China Sea.

PubMed

Peng, Shiqiu; Li, Yineng

2015-10-26

Drag coefficient (Cd) is an essential metric in the calculation of momentum exchange over the air-sea interface and thus has large impacts on the simulation or forecast of the upper ocean state associated with sea surface winds such as storm surges. Generally, Cd is a function of wind speed. However, the exact relationship between Cd and wind speed is still in dispute, and the widely-used formula that is a linear function of wind speed in an ocean model could lead to large bias at high wind speed. Here we establish a parabolic model of Cd based on storm surge observations and simulation in the South China Sea (SCS) through a number of tropical cyclone cases. Simulation of storm surges for independent Tropical cyclones (TCs) cases indicates that the new parabolic model of Cd outperforms traditional linear models.

A parabolic model of drag coefficient for storm surge simulation in the South China Sea

NASA Astrophysics Data System (ADS)

Peng, Shiqiu; Li, Yineng

2015-10-01

Drag coefficient (Cd) is an essential metric in the calculation of momentum exchange over the air-sea interface and thus has large impacts on the simulation or forecast of the upper ocean state associated with sea surface winds such as storm surges. Generally, Cd is a function of wind speed. However, the exact relationship between Cd and wind speed is still in dispute, and the widely-used formula that is a linear function of wind speed in an ocean model could lead to large bias at high wind speed. Here we establish a parabolic model of Cd based on storm surge observations and simulation in the South China Sea (SCS) through a number of tropical cyclone cases. Simulation of storm surges for independent Tropical cyclones (TCs) cases indicates that the new parabolic model of Cd outperforms traditional linear models.

Observations of neutral circulation at mid-latitudes during the Equinox Transition Study

NASA Technical Reports Server (NTRS)

Buonsanto, M. J.; Salah, J. E.; Miller, K. L.; Oliver, W. L.; Burnside, R. G.; Richards, P. G.

1988-01-01

Measurements of ion drift velocity made by the Millstone Hill incoherent scatter radar have been used to calculate the meridional neutral wind velocity during the Sept. 17 to 24, 1984 period. Strong daytime southward neutral surges were observed during the magnetically disturbed days of September 19 and 23, in contrast to the small daytime winds obtained as expected during the magnetically quiet days. The surge on September 19 was also seen at Arecibo. In addition, two approaches have been used to calculate the meridional wind component from the radar-derived height of the F-layer electron density peak. Results confirm the wind surge, particularly when the strong electric fields measured during the disturbed days are included in the calculations. The two approaches for the F-layer peak wind calculations are applied to the radar-derived electron density peak height as a function of latitude to study the variation of the southward daytime surges with latitude.

Glacier surge triggered by massive rock avalanche: Teleseismic and satellite image study of long-runout landslide onto RGO Glacier, Pamirs

NASA Astrophysics Data System (ADS)

Stark, C. P.; Wolovick, M.; Ekstrom, G.

2012-12-01

Glacier surges are thought to result from changes in resistance to sliding at the base of the ice mass. The reasons for such changes in basal conditions are not entirely understood, and this is in part because empirical constraints are severely limited. Recent work in the Karakoram and Pamir mountains, home to the majority of Earth's surging mountain glaciers, has boosted observational data, but has led to diametrically opposed interpretations of their glacier surging mechanics, ranging from thermal to hydrological switching. In this context we describe a surge of the RGO (Russian Geographical Society) Glacier in the Pamirs triggered by a massive rock avalanche off Mt Garmo in 2001. Initial reports pegged the RGO Glacier landslide as having been triggered in 2002 by strong ground motion originating from a nearby tectonic earthquake. We used multitemporal satellite imagery to establish failure must have struck in August-September 2001. This revised date was confirmed by reexamining teleseismic data recorded at stations in central Asia: it became clear that a landslide seismic source of magnitude Msw≈5.4 on 2001/09/02 had been misinterpreted as two tectonic sources located within kilometers of Mt Garmo. Exploiting a new technique we have developed for inverting long-period seismic waveforms, we show that a mass of rock and ice around 2.8×{}1011 kg collapsed to the SSE from an elevation of around 5800m, accelerated to a peak speed of about 60m/s, collided with the valley wall ˜ 2 km to the south and turned east to run out a further 6km over significant fractions of the accumulation and ablation zones of the RGO Glacier. Based on this estimate of landslide mass, we deduce that the supraglacial debris blanket generated by this rock avalanches averaged about 20m in thickness. By this reckoning, the Mt Garmo landslide is one of the largest in the last 33 years. Next we mapped the velocity field of the RGO Glacier over time using multitemporal satellite imagery. We performed image correlation velocimetry (sometimes known as feature tracking or optical flow velocimetry) using around 120 Landsat 7 ETM+ scenes spanning 1999 through 2012. Reliable velocity fields were generated even after the loss of scan-line correction (SLC-off scenes) in 2003. Our preliminary results reveal two phases of glacier surge. The first began within a few months of the rock avalanche during the winter of 2001, with ice flow speeds rising by more than an order of magnitude to nearly 1000m/y mid-glacier at the landslide toe, and propagating as a wave down-glacier in less than a year. This phase ended in 2002-3. The second, milder surge phase began in 2005 and ended in 2007. Each phase led to an advance of the terminus over several 100m. We interpret surge initiation as being the direct consequence of rock avalanche deposition on the glacier. To explore the apparent link between rock avalanching and glacier surging, we have developed a 2D thermomechanical, higher-order, flowline model coupled to a basal hydrology scheme. We conclude with a discussion of the behavior of this model when heavily perturbed by abrupt debris deposition, and we explore whether the occurrence of landslide-triggered surging can in any way advance our understanding of glacier surge mechanics in general.

Circadian rhythm disruption by a novel running wheel: Roles of exercise and arousal in blockade of the luteinizing hormone surge

PubMed Central

Duncan, Marilyn J.; Franklin, Kathleen M.; Peng, Xiaoli; Yun, Christopher; Legan, Sandra J.

2014-01-01

Exposure of proestrous Syrian hamsters to a new room, cage, and novel running wheel blocks the luteinizing hormone (LH) surge until the next day in ~75% of hamsters (Legan et al, 2010) [1]. The studies described here tested the hypotheses that 1) exercise and/or 2) orexinergic neurotransmission mediate novel wheel blockade of the LH surge and circadian phase advances. Female hamsters were exposed to a 14L:10D photoperiod and activity rhythms were monitored with infra-red detectors. In Expt. 1, to test the effect of exercise, hamsters received jugular cannulae and on the next day, proestrus (Day 1), shortly before zeitgeber time 5 (ZT 5, 7 hours before lights-off) the hamsters were transported to the laboratory. After obtaining a blood sample at ZT 5, the hamsters were transferred to a new cage with a novel wheel that was either freely rotating (unlocked), or locked until ZT 9, and exposed to constant darkness (DD). Blood samples were collected hourly for 2 days from ZT 5–11 under red light for determination of plasma LH levels by radioimmunoassay. Running rhythms were monitored continuously for the next 10–14 days. The locked wheels were as effective as unlocked wheels in blocking LH surges (no Day 1 LH surge in 6/9 versus 8/8 hamsters, P>0.05) and phase advances in the activity rhythms did not differ between the groups (P= 0.28), suggesting that intense exercise is not essential for novel wheel blockade and phase advance of the proestrous LH surge. Expt. 2 tested whether orexin neurotransmission is essential for these effects. Hamsters were treated the same as in Expt. 1 except they were injected (i.p.) at ZT 4.5 and 5 with either the orexin 1 receptor antagonist SB334867 (15 mg/kg per injection) or vehicle (25% DMSO in 2-hydroxypropyl-beta-cyclodextrin (HCD). SB-334867 inhibited novel wheel blockade of the LH surge (surges blocked in 2/6 SB334867-injected animals versus 16/18 vehicle-injected animals, P<0.02) and also inhibited wheel running and circadian phase shifts, indicating that activation of orexin 1 receptors is necessary for these effects. Expt. 3 tested the hypothesis that novel wheel exposure activates orexin neurons. Proestrous hamsters were transferred at ZT 5 to a nearby room within the animal facility and were exposed to a new cage with a locked or unlocked novel wheel or left in their home cages. At ZT 8, the hamsters were anesthetized, blood was withdrawn, they were perfused with fixative and brains were removed for immunohistochemical localization of Fos, GnRH, and orexin. Exposure to a wheel, whether locked or unlocked, suppressed circulating LH concentrations at ZT 8, decreased the proportion of Fos-activated GnRH neurons, and increased Fos-immunoreactive orexin cells. Unlocked wheels had greater effects than locked wheels on all three endpoints. Thus in a familiar environment, exercise potentiated the effect of the novel wheel on Fos expression because a locked wheel was not a sufficient stimulus to block the LH surge. In conclusion, these studies indicate that novel wheel exposure activates orexin neurons and that blockade of orexin 1 receptors prevents novel wheel blockade of the LH surge. These findings are consistent with a role for both exercise and arousal in mediating novel wheel blockade of the LH surge. PMID:24727338

Gamma-ray energy buildup factor calculations and shielding effects of some Jordanian building structures

NASA Astrophysics Data System (ADS)

Sharaf, J. M.; Saleh, H.

2015-05-01

The shielding properties of three different construction styles, and building materials, commonly used in Jordan, were evaluated using parameters such as attenuation coefficients, equivalent atomic number, penetration depth and energy buildup factor. Geometric progression (GP) method was used to calculate gamma-ray energy buildup factors of limestone, concrete, bricks, cement plaster and air for the energy range 0.05-3 MeV, and penetration depths up to 40 mfp. It has been observed that among the examined building materials, limestone offers highest value for equivalent atomic number and linear attenuation coefficient and the lowest values for penetration depth and energy buildup factor. The obtained buildup factors were used as basic data to establish the total equivalent energy buildup factors for three different multilayer construction styles using an iterative method. The three styles were then compared in terms of fractional transmission of photons at different incident photon energies. It is concluded that, in case of any nuclear accident, large multistory buildings with five layers exterior walls, style A, could effectively attenuate radiation more than small dwellings of any construction style.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tom, Nathan; Yu, Yi-Hsiang; Wright, Alan

The focus of this paper is to balance power absorption against structural loading for a novel fixed-bottom oscillating surge wave energy converter in both regular and irregular wave environments. The power-to-load ratio will be evaluated using pseudospectral control (PSC) to determine the optimum power-takeoff (PTO) torque based on a multiterm objective function. This paper extends the pseudospectral optimal control problem to not just maximize the time-averaged absorbed power but also include measures for the surge-foundation force and PTO torque in the optimization. The objective function may now potentially include three competing terms that the optimizer must balance. Separate weighting factorsmore » are attached to the surge-foundation force and PTO control torque that can be used to tune the optimizer performance to emphasize either power absorption or load shedding. To correct the pitch equation of motion, derived from linear hydrodynamic theory, a quadratic-viscous-drag torque has been included in the system dynamics; however, to continue the use of quadratic programming solvers, an iteratively obtained linearized drag coefficient was utilized that provided good accuracy in the predicted pitch motion. Furthermore, the analysis considers the use of a nonideal PTO unit to more accurately evaluate controller performance. The PTO efficiency is not directly included in the objective function but rather the weighting factors are utilized to limit the PTO torque amplitudes, thereby reducing the losses resulting from the bidirectional energy flow through a nonideal PTO. Results from PSC show that shedding a portion of the available wave energy can lead to greater reductions in structural loads, peak-to-average power ratio, and reactive power requirement.« less

Blockage of neonatal leptin signaling induces changes in the hypothalamus associated with delayed pubertal onset and modifications in neuropeptide expression during adulthood in male rats.

PubMed

Mela, Virginia; Jimenez, Sara; Freire-Regatillo, Alejandra; Barrios, Vicente; Marco, Eva-María; Lopez-Rodriguez, Ana-Belén; Argente, Jesús; Viveros, María-Paz; Chowen, Julie A

2016-12-01

The neonatal leptin surge, occurring from postnatal day (PND) 5 to 13 and peaking at PND9 in rodents, is important for the development of neuroendocrine circuits involved in metabolic control and reproductive function. We previously demonstrated that treatment with a leptin antagonist from PND 5 to 9, coincident with peak leptin levels in the neonatal surge, modified trophic factors and markers of cell turnover and neuronal maturation in the hypothalamus of peri-pubertal rats. The kisspeptin system and metabolic neuropeptide and hormone levels were also modified. Here our aim was to investigate if the timing of pubertal onset is altered by neonatal leptin antagonism and if the previously observed peripubertal modifications in hormones and neuropeptides persist into adulthood and affect male sexual behavior. To this end, male Wistar rats were treated with a pegylated super leptin antagonist (5mg/kg, s.c.) from PND 5 to 9 and killed at PND102-103. The appearance of external signs of pubertal onset was delayed. Hypothalamic kiss1 mRNA levels were decreased in adult animals, but sexual behavior was not significantly modified. Although there was no effect on body weight or food intake, circulating leptin, insulin and triglyceride levels were increased, while hypothalamic leptin receptor, POMC and AgRP mRNA levels were decreased. In conclusion, alteration of the neonatal leptin surge can modify the timing of pubertal onset and have long-term effects on hypothalamic expression of reproductive and metabolic neuropeptides. Copyright © 2016 Elsevier Inc. All rights reserved.

Future hurricane storm surge risk for the U.S. gulf and Florida coasts based on projections of thermodynamic potential intensity

DOE Office of Scientific and Technical Information (OSTI.GOV)

Balaguru, Karthik; Judi, David R.; Leung, L. Ruby

Coastal populations in the global tropics and sub-tropics are vulnerable to the devastating impacts of hurricane storm surge and this risk is only expected to rise under climate change. In this study, we address this issue for the U.S. Gulf and Florida coasts. Using the framework of Potential Intensity, observations and output from coupled climate models, we show that the future large-scale thermodynamic environment may become more favorable for hurricane intensification. Under the RCP 4.5 emissions scenario and for the peak hurricane season months of August–October, we show that the mean intensities of Atlantic hurricanes may increase by 1.8–4.2 %more » and their lifetime maximum intensities may increase by 2.7–5.3 % when comparing the last two decades of the 20th and 21st centuries. We then combine our estimates of hurricane intensity changes with projections of sea-level rise to understand their relative impacts on future storm surge using simulations with the National Weather Service’s SLOSH (Sea, Lake, and Overland Surges from Hurricanes) model for five historical hurricanes that made landfall in the Gulf of Mexico and Florida. Considering uncertainty in hurricane intensity changes and sea-level rise, our results indicate a median increase in storm surge ranging between 25 and 47 %, with changes in hurricane intensity increasing future storm surge by about 10 % relative to the increase that may result from sea level rise alone, with highly non-linear response of population at risk.« less

Simulated storm surge effects on freshwater coastal wetland soil porewater salinity and extractable ammonium levels: Implications for marsh recovery after storm surge

NASA Astrophysics Data System (ADS)

McKee, M.; White, J. R.; Putnam-Duhon, L. A.

2016-11-01

Coastal wetland systems experience both short-term changes in salinity, such as those caused by wind-driven tides and storm surge, and long-term shifts caused by sea level rise. Salinity increases associated with storm surge are known to have significant effects on soil porewater chemistry, but there is little research on the effect of flooding length on salt penetration depth into coastal marsh soils. A simulated storm surge was imposed on intact soil columns collected from a non-vegetated mudflat and a vegetated marsh site in the Wax Lake Delta, LA. Triplicate intact cores were continuously exposed to a 35 salinity water column (practical salinity scale) for 1, 2, and 4 weeks and destructively sampled in order to measure porewater salinity and extractable NH4sbnd N at two cm depth intervals. Salinity was significantly higher in the top 8 cm for both the marsh and mudflat cores after one week of flooding. After four weeks of flooding, salinity was significantly higher in marsh and mudflat cores compared to the control (no salinity) cores throughout the profile for both sites. Extractable ammonium levels increased significantly in the marsh cores throughout the experiment, but there was only a marginally (p < 0.1) significant increase seen in the mudflat cores. Results indicate that porewater salinity levels can become significantly elevated within a coastal marsh soil in just one week. This vertical intrusion of salt can potentially negatively impact macrophytes and associated microbial communities for significantly longer term post-storm surge.

The Low-Level Flow Along the Gulf of California During the North American Monsoon.

NASA Astrophysics Data System (ADS)

Bordoni, S.; Stevens, B.

2007-05-01

Six-years (1999-2004) of QuikSCAT near-surface ocean winds are used to study the flow over the northeast Pacific and the Gulf of California (GoC) during the North American Monsoon season. The wind data show that the onset of the summer season is accompanied by a reversal of the flow along the GoC, with the establishment of a mean southerly wind throughout the gulf. This reversal occurs in late spring and precedes the onset of the monsoonal rains. In the heart of the monsoon season, the time-mean flow is found to be composed of periods of enhanced southerly winds associated with gulf surges. The role that gulf surges play in modulating the GoC mean southerly flow is further explored by performing an EOF analysis of the summertime daily wind anomalies. A gulf surge mode emerges from this analysis as the leading EOF, with the corresponding principal component time series interpretable as an objective index for gulf surge occurrence. This index is used as a reference time series for regression analysis, to explore the relationship between gulf surges and precipitation over the core and marginal regions of the monsoon, as well as the manifestation of these transient events in the large-scale circulation. It is found that, although seemingly mesoscale features confined over the GoC, gulf surges are intimately linked to patterns of large-scale variability of the eastern Pacific ITCZ and greatly contribute to the definition of the northward extent of the monsoonal rains.

Recycle dynamics during centrifugal compressor ESD, start-up and surge control

DOE Office of Scientific and Technical Information (OSTI.GOV)

Botros, K.K.; Jones, B.J.; Richards, D.J.

1996-12-31

Recycle systems are important components in the operation of centrifugal compressor stations. They are essential during a start-up operation, for surge protection and for emergency shutdown (ESD). These operations are inherently dynamic where interactions between equipment, control and gas flow occur in a complex manner with the associated risk of compressor surge. Of particular importance are the effects or recycle system capacity, the recycle valve characteristics, check valve dynamic behavior, piping geometry and capacitance around the compressor unit, and the performance characteristics of the centrifugal compressor itself. This paper presents numerical results of the effects of some of these parametersmore » on surge control, ESD and unit startup. These parameters are: (1) The effects of damping the surge control flow signal in an attempt to suppress the signal noise, on the integrity of the surge control system; (2) The effects of recycle valve characteristics, stroke time and valve capacity on ESD; (3) The effects of recycle line size on ESD; and (4) The effects of the recycle valve closing time (or rate) on the startup operation, with the intent of shortening this time to minimum for environmental reasons. Results were obtained from the solution of the pertinent dynamic equations describing the gas and equipment dynamics which has been verified against field and laboratory measurements. The samples presented in this paper were applied to a 24 MW natural gas compressor station on the NOVA Gas Transmission system, and to a scale-down laboratory model. Influence of other parameters from this investigation were published elsewhere and are cited in the reference section.« less

Crevasses as indicators of surge dynamics in the Bering Bagley Glacier System, Alaska: Numerical experiments and comparison to image data analysis

NASA Astrophysics Data System (ADS)

Trantow, T.; Herzfeld, U. C.

2016-12-01

During a surge, sections of a glacier will accelerate 10-100 times their normal flow velocity resulting in sudden changes in the local stress regime. A glacier surface can fracture when a critical stress threshold is exceeded resulting in surface deformation, i.e. crevassing. During a recent field campaign to Bering Glacier, Alaska, in 2011 (and later in 2012, 2013), large scale deformation of the glacier surface was observed, indicating a major surge phase had recently occurred (Herzfeld et al. 2013). In the current study, geostatistical analysis is applied to satellite imagery to characterize the surge-induced crevasses that were present during the surge phase that began in early 2011. Results are compared to a three-dimensional, isothermal, full-Stokes model of Bering Glacier implemented in the open-source finite element software Elmer/Ice, which predicts locations and orientations of crevassing based on a failure criterion involving the magnitude(s) of the principal stress(es). Since most of the movement during a surge is due to basal sliding from decreased friction at the ice-bedrock interface, a relatively accurate representation of the the basal conditions is required to accurately model the ice dynamics and hence its stress regime. To achieve this, we invert velocity data derived from image correlation to attain estimations of the basal friction coefficient that governs basal sliding in the model. The methods employed here provide a procedure to identify discrepancies between observations and models of ice-flow during acceleration events.

Revealing glacier flow and surge dynamics from animated satellite image sequences: examples from the Karakoram

NASA Astrophysics Data System (ADS)

Paul, F.

2015-11-01

Although animated images are very popular on the internet, they have so far found only limited use for glaciological applications. With long time series of satellite images becoming increasingly available and glaciers being well recognized for their rapid changes and variable flow dynamics, animated sequences of multiple satellite images reveal glacier dynamics in a time-lapse mode, making the otherwise slow changes of glacier movement visible and understandable to the wider public. For this study, animated image sequences were created for four regions in the central Karakoram mountain range over a 25-year time period (1990-2015) from freely available image quick-looks of orthorectified Landsat scenes. The animations play automatically in a web browser and reveal highly complex patterns of glacier flow and surge dynamics that are difficult to obtain by other methods. In contrast to other regions, surging glaciers in the Karakoram are often small (10 km2 or less), steep, debris-free, and advance for several years to decades at relatively low annual rates (about 100 m a-1). These characteristics overlap with those of non-surge-type glaciers, making a clear identification difficult. However, as in other regions, the surging glaciers in the central Karakoram also show sudden increases of flow velocity and mass waves travelling down glacier. The surges of individual glaciers are generally out of phase, indicating a limited climatic control on their dynamics. On the other hand, nearly all other glaciers in the region are either stable or slightly advancing, indicating balanced or even positive mass budgets over the past few decades.

Characterizing the UV-to-NIR shape of the dust attenuation curve of IR luminous galaxies up to z ˜ 2

NASA Astrophysics Data System (ADS)

Lo Faro, B.; Buat, V.; Roehlly, Y.; Alvarez-Marquez, J.; Burgarella, D.; Silva, L.; Efstathiou, A.

2017-12-01

In this work, we investigate the far-ultraviolet (UV) to near-infrared (NIR) shape of the dust attenuation curve of a sample of IR-selected dust obscured (ultra)luminous IR galaxies at z ∼ 2. The spectral energy distributions (SEDs) are fitted with Code Investigating GALaxy Emission, a physically motivated spectral-synthesis model based on energy balance. Its flexibility allows us to test a wide range of different analytical prescriptions for the dust attenuation curve, including the well-known Calzetti and Charlot & Fall curves, and modified versions of them. The attenuation curves computed under the assumption of our reference double power-law model are in very good agreement with those derived, in previous works, with radiative transfer (RT) SED fitting. We investigate the position of our galaxies in the IRX-β diagram and find this to be consistent with greyer slopes, on average, in the UV. We also find evidence for a flattening of the attenuation curve in the NIR with respect to more classical Calzetti-like recipes. This larger NIR attenuation yields larger derived stellar masses from SED fitting, by a median factor of ∼1.4 and up to a factor ∼10 for the most extreme cases. The star formation rate appears instead to be more dependent on the total amount of attenuation in the galaxy. Our analysis highlights the need for a flexible attenuation curve when reproducing the physical properties of a large variety of objects.

Numerical simulation of rotating stall and surge alleviation in axial compressors

NASA Astrophysics Data System (ADS)

Niazi, Saeid

Axial compression systems are widely used in many aerodynamic applications. However, the operability of such systems is limited at low-mass flow rates by fluid dynamic instabilities. These instabilities lead the compressor to rotating stall or surge. In some instances, a combination of rotating stall and surge, called modified surge, has also been observed. Experimental and computational methods are two approaches for investigating these adverse aerodynamic phenomena. In this study, numerical investigations have been performed to study these phenomena, and to develop control strategies for alleviation of rotating stall and surge. A three-dimensional unsteady Navier-Stokes analysis capable of modeling multistage turbomachinery components has been developed. This method uses a finite volume approach that is third order accurate in space, and first or second order in time. The scheme is implicit in time, permitting the use of large time steps. A one-equation Spalart-Allmaras model is used to model the effects of turbulence. The analysis is cast in a very general form so that a variety of configurations---centrifugal compressors and multistage compressors---may be analyzed with minor modifications to the analysis. Calculations have been done both at design and off-design conditions for an axial compressor tested at NASA Glenn Research Center. At off-design conditions the calculations show that the tip leakage flow becomes strong, and its interaction with the tip shock leads to compressor rotating stall and modified surge. Both global variations to the mass flow rate, associated with surge, and azimuthal variations in flow conditions indicative of rotating stall, were observed. It is demonstrated that these adverse phenomena may be eliminated, and stable operation restored, by the use of bleed valves located on the diffuser walls. Two types of controls were examined: open-loop and closed-loop. In the open-loop case mass is removed at a fixed, preset rate from the diffuser. In the closed-loop case, the rate of bleed is linked to pressure fluctuations upstream of the compressor face. The bleed valve is activated when the amplitude of pressure fluctuations sensed by the probes exceeds a certain range. Calculations show that both types of bleeding eliminate both rotating stall and modified surge, and suppress the precursor disturbances upstream of the compressor face. It is observed that smaller amounts of compressed air need to be removed with the closed-loop control, as compared to open-loop control.

Surge capacity logistics: care of the critically ill and injured during pandemics and disasters: CHEST consensus statement.

PubMed

Einav, Sharon; Hick, John L; Hanfling, Dan; Erstad, Brian L; Toner, Eric S; Branson, Richard D; Kanter, Robert K; Kissoon, Niranjan; Dichter, Jeffrey R; Devereaux, Asha V; Christian, Michael D

2014-10-01

Successful management of a pandemic or disaster requires implementation of preexisting plans to minimize loss of life and maintain control. Managing the expected surges in intensive care capacity requires strategic planning from a systems perspective and includes focused intensive care abilities and requirements as well as all individuals and organizations involved in hospital and regional planning. The suggestions in this article are important for all involved in a large-scale disaster or pandemic, including front-line clinicians, hospital administrators, and public health or government officials. Specifically, this article focuses on surge logistics-those elements that provide the capability to deliver mass critical care. The Surge Capacity topic panel developed 23 key questions focused on the following domains: systems issues; equipment, supplies, and pharmaceuticals; staffing; and informatics. Literature searches were conducted to identify studies upon which evidence-based recommendations could be made. The results were reviewed for relevance to the topic, and the articles were screened by two topic editors for placement within one of the surge domains noted previously. Most reports were small scale, were observational, or used flawed modeling; hence, the level of evidence on which to base recommendations was poor and did not permit the development of evidence-based recommendations. The Surge Capacity topic panel subsequently followed the American College of Chest Physicians (CHEST) Guidelines Oversight Committee's methodology to develop suggestion based on expert opinion using a modified Delphi process. This article presents 22 suggestions pertaining to surge capacity mass critical care, including requirements for equipment, supplies, and pharmaceuticals; staff preparation and organization; methods of mitigating overwhelming patient loads; the role of deployable critical care services; and the use of transportation assets to support the surge response. Critical care response to a disaster relies on careful planning for staff and resource augmentation and involves many agencies. Maximizing the use of regional resources, including staff, equipment, and supplies, extends critical care capabilities. Regional coalitions should be established to facilitate agreements, outline operational plans, and coordinate hospital efforts to achieve predetermined goals. Specialized physician oversight is necessary and if not available on site, may be provided through remote consultation. Triage by experienced providers, reverse triage, and service deescalation may be used to minimize ICU resource consumption. During a temporary loss of infrastructure or overwhelmed hospital resources, deployable critical care services should be considered.

Verification of an ensemble prediction system for storm surge forecast in the Adriatic Sea

NASA Astrophysics Data System (ADS)

Mel, Riccardo; Lionello, Piero

2014-12-01

In the Adriatic Sea, storm surges present a significant threat to Venice and to the flat coastal areas of the northern coast of the basin. Sea level forecast is of paramount importance for the management of daily activities and for operating the movable barriers that are presently being built for the protection of the city. In this paper, an EPS (ensemble prediction system) for operational forecasting of storm surge in the northern Adriatic Sea is presented and applied to a 3-month-long period (October-December 2010). The sea level EPS is based on the HYPSE (hydrostatic Padua Sea elevation) model, which is a standard single-layer nonlinear shallow water model, whose forcings (mean sea level pressure and surface wind fields) are provided by the ensemble members of the ECMWF (European Center for Medium-Range Weather Forecasts) EPS. Results are verified against observations at five tide gauges located along the Croatian and Italian coasts of the Adriatic Sea. Forecast uncertainty increases with the predicted value of the storm surge and with the forecast lead time. The EMF (ensemble mean forecast) provided by the EPS has a rms (root mean square) error lower than the DF (deterministic forecast), especially for short (up to 3 days) lead times. Uncertainty for short lead times of the forecast and for small storm surges is mainly caused by uncertainty of the initial condition of the hydrodynamical model. Uncertainty for large lead times and large storm surges is mainly caused by uncertainty in the meteorological forcings. The EPS spread increases with the rms error of the forecast. For large lead times the EPS spread and the forecast error substantially coincide. However, the EPS spread in this study, which does not account for uncertainty in the initial condition, underestimates the error during the early part of the forecast and for small storm surge values. On the contrary, it overestimates the rms error for large surge values. The PF (probability forecast) of the EPS has a clear skill in predicting the actual probability distribution of sea level, and it outperforms simple "dressed" PF methods. A probability estimate based on the single DF is shown to be inadequate. However, a PF obtained with a prescribed Gaussian distribution and centered on the DF value performs very similarly to the EPS-based PF.

Simulating storm surge inundation and damage potential within complex port facilities

NASA Astrophysics Data System (ADS)

Mawdsley, Robert; French, Jon; Fujiyama, Taku; Achutan, Kamalasudhan

2017-04-01

Storm surge inundation of port facilities can cause damage to critical elements of infrastructure, significantly disrupt port operations and cause downstream impacts on vital supply chains. A tidal surge in December 2013 in the North Sea partly flooded the Port of Immingham, which handles the largest volume of bulk cargo in the UK including major flows of coal and biomass for power generation. This flooding caused damage to port and rail transport infrastructure and disrupted operations for several weeks. This research aims to improve resilience to storm surges using hydrodynamic modelling coupled to an agent-based model of port operations. Using the December 2013 event to validate flood extent, depth and duration, we ran a high resolution hydrodynamic simulation using the open source Telemac 2D finite element code. The underlying Digital Elevation Model (DEM) was derived from Environment Agency LiDAR data, with ground truthing of the flood defences along the port frontage. Major infrastructure and buildings are explicitly resolved with varying degrees of permeability. Telemac2D simulations are run in parallel and take only minutes on a single 16 cpu compute node. Inundation characteristics predicted using Telemac 2D differ from a simple Geographical Information System 'bath-tub' analysis of the DEM based upon horizontal application of the maximum water level across the port topography. The hydrodynamic simulation predicts less extensive flooding and more closely matches observed flood extent. It also provides more precise depth and duration curves. Detailed spatial flood depth and duration maps were generated for a range of tide and surge scenarios coupled to mean sea-level rise projections. These inundation scenarios can then be integrated with critical asset databases and an agent-based model of port operation (MARS) that is capable of simulating storm surge disruption along wider supply chains. Port operators are able to act on information from a particular flood scenario to perform adaptive responses (e.g. pre-emptive relocation of equipment), as well as estimate the likely duration of any disruption to port and supply chain operation. High resolution numerical inundation modelling, coupled to accurate storm surge forecasting and an agent based port operation model, thus has the potential to significantly reduce damage and disruption costs associated with storm surge impacts on port infrastructure and systems.

A Simple Graphical Method for Quantification of Disaster Management Surge Capacity Using Computer Simulation and Process-control Tools.

PubMed

Franc, Jeffrey Michael; Ingrassia, Pier Luigi; Verde, Manuela; Colombo, Davide; Della Corte, Francesco

2015-02-01

Surge capacity, or the ability to manage an extraordinary volume of patients, is fundamental for hospital management of mass-casualty incidents. However, quantification of surge capacity is difficult and no universal standard for its measurement has emerged, nor has a standardized statistical method been advocated. As mass-casualty incidents are rare, simulation may represent a viable alternative to measure surge capacity. Hypothesis/Problem The objective of the current study was to develop a statistical method for the quantification of surge capacity using a combination of computer simulation and simple process-control statistical tools. Length-of-stay (LOS) and patient volume (PV) were used as metrics. The use of this method was then demonstrated on a subsequent computer simulation of an emergency department (ED) response to a mass-casualty incident. In the derivation phase, 357 participants in five countries performed 62 computer simulations of an ED response to a mass-casualty incident. Benchmarks for ED response were derived from these simulations, including LOS and PV metrics for triage, bed assignment, physician assessment, and disposition. In the application phase, 13 students of the European Master in Disaster Medicine (EMDM) program completed the same simulation scenario, and the results were compared to the standards obtained in the derivation phase. Patient-volume metrics included number of patients to be triaged, assigned to rooms, assessed by a physician, and disposed. Length-of-stay metrics included median time to triage, room assignment, physician assessment, and disposition. Simple graphical methods were used to compare the application phase group to the derived benchmarks using process-control statistical tools. The group in the application phase failed to meet the indicated standard for LOS from admission to disposition decision. This study demonstrates how simulation software can be used to derive values for objective benchmarks of ED surge capacity using PV and LOS metrics. These objective metrics can then be applied to other simulation groups using simple graphical process-control tools to provide a numeric measure of surge capacity. Repeated use in simulations of actual EDs may represent a potential means of objectively quantifying disaster management surge capacity. It is hoped that the described statistical method, which is simple and reusable, will be useful for investigators in this field to apply to their own research.

High storm surge events in Venice and the 11-yr solar cycle

NASA Astrophysics Data System (ADS)

Barriopedro, David; García-Herrera, Ricardo; Lionello, Piero; Pino, Cosimo

2010-05-01

In the last years the Venice lagoon has received much attention as a case of coastal vulnerability, mainly because of relative sea level rise and increase frequency of storm surge events, the so-called "aqua alta", which, particularly during autumn, cause the flooding of the Venice historical city center. Long-term fluctuations in solar activity and large-scale climate patterns have been suggested as feasible factors of flooding variability. This study explores the long-term frequency variability of High Surge Events (HSE) in Venice for the period 1948-2008 and its modulation by the 11-yr solar cycle. A significant decadal variability in the frequency of HSE is found in good correspondence with the 11-yr cycle, solar maxima being associated to a significant increase of the October-November-December HSE frequency. A Storm Surge Pattern (SSP), i.e. the seasonal 1000 hPa height pattern associated to increased frequency of HSE, is identified and found similar to the positive phase of the main variability mode of the regional atmospheric circulation (EOF1). However, further analyses indicate that the increase of HSE in solar maxima cannot be simply explained by a higher recurrence of positive EOF1 phases during high solar years. It rather seems that solar activity modulates the spatial patterns of the atmospheric circulation (EOF) and the favorable conditions for HSE occurrence (SSP). Thus, under solar maxima, the occurrence of HSE is enhanced by the EOF1, namely a large-scale wave train pattern that is symptomatic of storm track paths over northern Europe. Solar minima reveal a substantially different and less robust SSP, consisting of a meridionally oriented dipole with a preferred southward path of storm track activity, which is not associated to any EOF during low solar periods. It is concluded that solar activity plays an indirect role in the frequency of HSE by modulating the spatial patterns of the main modes of atmospheric regional variability, the favorable patterns for HSE occurrence and their mutual relationships, so that constructive interaction between them is enhanced during solar maxima and inhibited in solar minima.

Obstructive sleep apnea syndrome and hypertension: ambulatory blood pressure.

PubMed

Kario, Kazuomi

2009-06-01

Obstructive sleep apnea syndrome (OSAS) is an independent risk factor for hypertension and cardiovascular disease. OSAS is the frequent underlying disease of secondary hypertension and resistant hypertension. OSAS increases both daytime and night-time ambulatory blood pressures through the activation of various neurohumoral factors including the sympathetic nervous system and the renin-angiotensin-aldosterone system. In particular, OSAS predominantly increases ambulatory BP during sleep compared with the awake period, with the result that OSAS is likely to be associated with the non-dipping pattern (diminished nocturnal BP fall) or riser pattern (higher sleep BP than awake BP) of nocturnal BP. An additional characteristic of ABP in OSAS is increased BP variability. The newly developed non-invasive hypoxia-trigger BP-monitoring system detected marked midnight BP surges (ranging from around 10 to 100 mm Hg) during sleep in OSAS patients. The exaggerated BP surge may trigger OSAS-related cardiovascular events occurring during sleep. Clinically, as nocturnal hypoxia is the determinant of morning minus evening BP difference (ME difference), OSAS should be strongly suspected when morning BP cannot be controlled <135/85 mm Hg with increased ME difference even by the specific antihypertensive medications targeting morning hypertension such as bedtime dosing of antihypertensive drugs. Understanding the characteristics of OSAS-related hypertension is essentially important to achieve perfect BP control over a 24-h period, including the sleep period, for more effective prevention of cardiovascular disease.

Assessment of hospital surge capacity using the MACSIM simulation system: a pilot study.

PubMed

Lennquist Montán, K; Riddez, L; Lennquist, S; Olsberg, A C; Lindberg, H; Gryth, D; Örtenwall, P

2017-08-01

The aim of this study was to use a simulation model developed for the scientific evaluation of methodology in disaster medicine to test surge capacity (SC) in a major hospital responding to a simulated major incident with a scenario copied from a real incident. The tested hospital was illustrated on a system of magnetic boards, where available resources, staff, and patients treated in the hospital at the time of the test were illustrated. Casualties were illustrated with simulation cards supplying all data required to determine procedures for diagnosis and treatment, which all were connected to real consumption of time and resources. The first capacity-limiting factor was the number of resuscitation teams that could work parallel in the emergency department (ED). This made it necessary to refer severely injured to other hospitals. At this time, surgery (OR) and intensive care (ICU) had considerable remaining capacity. Thus, the reception of casualties could be restarted when the ED had been cleared. The next limiting factor was lack of ventilators in the ICU, which permanently set the limit for SC. At this time, there was still residual OR capacity. With access to more ventilators, the full surgical capacity of the hospital could have been utilized. The tested model was evaluated as an accurate tool to determine SC. The results illustrate that SC cannot be determined by testing one single function in the hospital, since all functions interact with each other and different functions can be identified as limiting factors at different times during the response.

Observations on Rotating Cavitation and Cavitation Surge from the Development of the Fastrac Engine Turbopump

NASA Technical Reports Server (NTRS)

Zoladz, Thomas F.

2000-01-01

Observations regarding rotating cavitation and cavitation surge experienced during the development of the Fastrac engine turbopump are discussed. Detailed observations acquired from the analysis of both water flow and liquid oxygen test data are offered in this paper. Scaling and general comparison of rotating cavitation between water flow and liquid oxygen testing are discussed. Complex data features linking the localized rotating cavitation mechanism of the inducer to system surge components are described in detail. Finally a description of a lumped-parameter hydraulic system model developed to better understand observed data is given.

Overview of Rotating Cavitation and Cavitation Surge in the Fastrac Engine LOX Turbopump

NASA Technical Reports Server (NTRS)

Zoladz, Thomas; Turner, Jim (Technical Monitor)

2001-01-01

Observations regarding rotating cavitation and cavitation surge experienced during the development of the Fastrac 60 Klbf engine turbopump are discussed. Detailed observations from the analysis of both water flow and liquid oxygen test data are offered. Scaling and general comparison of rotating cavitation between water flow and liquid oxygen testing are discussed. Complex data features linking the localized rotating cavitation mechanism of the inducer to system surge components are described in detail. Finally a description of a simple lumped-parameter hydraulic system model developed to better understand observed data is given.