Loss Of Circulation Research Articles

Efficacy of cerebrolysin on dentate gyrus of hippocampus after experimentally induced acute ischemic stroke in adult albino rats (Histological, immunohistochemical and biochemical study)

Background: Acute ischemic stroke (AIS) is a brain medical disorder characterized by the sudden loss of blood circulation to an area of the brain, resulting in a loss of its neurologic function. Cerebrolysin is a mixture of neuropeptides and free amino acids. Aim of the work: This study aimed to evaluate the role of cerebrolysin in ameliorating the histological, immunohistochemical and biochemical harm in post ischemic stroke and also to assess its dose dependent effect.Materials and Methods: Thirty adult male rats were divided into 3 equal groups; control, ischemic and post ischemic treated groups. After dissecting hippocampal dentate gyrus prepared sections were stained with hematoxylin and eosin, Erβ and calretinin proteins. Oxidative stress parameters, TNF α, and HSP-70 assay. Also, Gh receptor gene expression and DNA fragmentation test were measured. Immunoperoxidase reactions for GFAPin astrocyte was estimated. Statistical analysis was conducted. Results: Ischemia group showed decrease number of granule cells with small dark stained nuclei, areas of cell loss and numerous spindle shaped cells in the sub-granular zone. A faint positive immunoreaction for ERβ in nuclei of granular cells and negative reaction for calretinin was detected in granule cells. Antioxidant enzymes in the brain tissue as MDA,TNF α and HSP-70 were significantly elevated in ischemic group compared to control and post ischemic treated groups. Gh receptor gene were decreased, while Fragmentation index of DNA was significantly increased. Administration of 2.5 mg/kg cerebrolysinshowed partial improvement, whereas, 5 mg/kg dose displayed more ameliorative effects. Increased GFAP immune-expression in the cytoplasm of astrocytes in ischemic group compared to control and post ischemic treated groups. Conclusion: Cerebrolysin was effective in experimentally induced AIS (Acute ischemic stroke) in a dose-dependent manner as proved by improving the histological structure, immunohistochemical reactions and biochemical parameters of the dentate gyrus of hippocampus in adult male albino rats.

Case Histories of GPR for Animal Burrows Mapping and Geometry.

Ground-penetrating radar (GPR) has a wide range of applications, from geologic mapping to concrete inspection. A recently emerging GPR application is deployment in biological investigations as a non-invasive technique. Geophysical mapping of features such as tree roots and turtle burrows has proved valuable for the understanding of these subsurface systems for ecological, environmental, or engineering purposes. Four case histories of GPR investigations pertaining to animal burrows are described: cutter ants in Brazil, groundhogs in Michigan, and groundhogs, and burrowing bees in Pennsylvania. Cutter ants (Atta spp.) in Amazonian Brazil are known to construct burrows of nearly the same dimensions as groundhogs as they excavate galleries up to 7 m deep for leaf storage. Cutter ant burrows are hazardous to heavy equipment and may also cause loss of mud circulation during rotary drilling. Groundhogs (Marmota monax), found throughout the United States, cause unseen hazards, particularly for equestrian facilities where a sudden collapse can cause severe injuries to both horse and rider. Burrowing bees (Colletes inaequalis) are common in the northeastern United States. The size of the bee burrows is significantly smaller than that of the cutter ants and the groundhogs. The data for these surveys were collected over a twenty-year span, crossing several generations of survey equipment and processing techniques. Together, these four case histories highlight the historic and current capabilities of GPR systems applied to mapping subsurface burrow systems. These examples demonstrate the important impact near surface heterogeneities have in altering ecological, environmental, or engineering systems and the utility of GPR for mapping such heterogeneities.

Real-Time Determination of Rheological Properties of Spud Drilling Fluids Using a Hybrid Artificial Intelligence Technique

The rheological properties of the drilling fluid play a key role in controlling the drilling operation. Knowledge of drilling fluid rheological properties is very crucial for drilling hydraulic calculations required for hole cleaning optimization. Measuring the rheological properties during drilling sometimes is a time-consuming process. Wrong estimation of these properties may lead to many problems, such as pipe sticking, loss of circulation, and/or well control issues. The aforementioned problems increase the non-productive time and the overall cost of the drilling operations. In this paper, the frequent drilling fluid measurements (mud density, Marsh funnel viscosity (MFV), and solid percent) are used to estimate the rheological properties of bentonite spud mud. Artificial neural network (ANN) technique was combined with the self-adaptive differential evolution algorithm (SaDe) to develop an optimum ANN model for each rheological property using 1029 data points. The SaDe helped to optimize the best combination of parameters for the ANN models. For the first time, based on the developed ANN models, empirical equations are extracted for each rheological parameter. The ANN models predicted the rheological properties from the mud density, MFV, and solid percent with high accuracy (average absolute percentage error (AAPE) less than 5% and correlation coefficient higher than 95%). The developed apparent viscosity model was compared with the available models in the literature using the unseen dataset. The SaDe-ANN model outperformed the other models which overestimated the apparent viscosity of the spud drilling fluid. The developed models will help drilling engineers to predict the rheological properties every 15–20 min. This will help to optimize hole cleaning and avoid pipe sticking and loss of circulation where bentonite spud mud is used. No additional equipment or special software is required for applying the new method.

Preventing the Loss, Improving the Properties of the Circulating Material to Seal Fractures and a Depleted Section of the Well

The loss of circulation is an extremely unhealthy phenomenon for drilling, as the liquid solution leaving in the reservoir often leaves the entire drilled breed in the borehole and, in most cases, all the large particles in the solution itself. The settling masses are compacted and can create around the drill tool dense shell and also cause so-called clamp tool-a phenomenon when to remove the drill pipe poses great difficulties. The methods devise in the current research for loss of circulation or eliminated are a reduction of mud density until its hydrostatic pressure becomes equal to the reservoir and Pumping Mudpack with a high concentration of clogging additives in the absorption zone. In addition, the clogging materials to combat the loss of circulation can be used as additives in circulating drilling mud in the drilling of sediment prone to absorption. For the control of absorption, it is possible to use saw dust, flaky and granulated materials or a mixture of all three [1-6]. The flaky materials include cellophane, mica, the husk of sunflower seeds cotton, nut shells. The granulated materials include grinding rubber or asbestos, asphalt. This method differs from other methods in that in order to prevent the loss of the drilling solution to the composition of the chemical compound can be improved by increasing the agent's viscosity in cracks or pores clogging. A series of experiments was conducted to determine the optimal viscosity of the agent, consisting of urea formaldehyde with ammonium sulfate and bentonite. Ammonium sulfate is added to urea formaldehyde in the ratio of 1/5. In a series of experiments, the ratio of chemicals was increased properly. Measurement of solution viscosity was performed by rheometer up to 500MPa. Since there are errors in Rheometer after 500MPA, the measurement of viscosity began by hand with the help of 200ml of the test tube, weights and steel ball. The obtained results satisfied the requirement for the loss of the chemical of drilling mud. Thus, on the basis of the experiments, it was found that to prevent the loss of the drilling solution to improve the composition of the chemical compound by increasing the viscosity of the agent. This will save the amount of mud and expensive additives save time for drilling and prevent clogging of potentially productive drilling areas.

Прогнозирование и предупреждение поглощений в серпуховском ярусе при бурении скважин на месторождениях Самарской области

Прогнозирование и предупреждение поглощений в серпуховском ярусе при бурении скважин на месторождениях Самарской области

Modified mathematical model for variable fill fluid coupling

Variable fill fluid couplings are used in the speed control units. Also, variation in coupling oil volume is used in adapting one size of coupling to a wider range of power transmission applications. Available model for the partially filled fluid couplings, has a good performance for couplings with fixed amount of oil but their performance will be degraded if they are used for the variable fill couplings. In this paper, the current model for partially filled fluid couplings is modified to have better performance for variable fill couplings. For this purpose, the circulation loss calculation is modified and also, the effect of oil temperature variations and blade thickness are included in the model. The effect of these modification on the model performance are investigated in couple of simulations. Comparing the simulation results with the available experimental data shows that the suggested modifications can improve the model performance very well.

Simulation for dynamics of transient ischemic attacks with thermal infrared imaging

Stroke is characterized by the sudden loss of blood circulation to an area of the brain, resulting in a corresponding loss of neurologic function in a patient. According to current methodological recommendations, it is possible to perform surgical and drug treatment to minimize the damage from acute stroke in the first 3-6 hours after the onset of transient ischemic attacks, which is often difficult to identity for emergency physician or clinician. Thermal infrared imaging could serve as a fast non-invasive test to detect asymmetrical pattern in facial temperature of patient as a predictor for vessel occlusion during acute stroke. We develop a software-driven model to simulate for dynamics of facial surface temperature distribution with transient ischemic attacks. The implemented model is designed to develop and debug algorithms for automated analysis of the temperature dysregulation at the processing of patient thermal infrared recording.

Calculation analysis of the processes of boric acid mass transfer in the WWER core in boiling emergency mode

In this paper the processes of boric acid mass transfer in a WWER-TOI nuclear reactor core in case of the accidents with main circulation pipeline rupture and loss of all AC power supply are considered. The heat removal from the WWER-TOI reactor in case of an emergency process is determined by the use of the passive heat removal and passive core cooling systems. Passive core cooling system of WWER-TOI consists of three stages of hydro accumulators. These systems provide reactor cooling by feed of boric acid solution with concentration of 16 g H3BO3/kg H2O. In view of length of accident process, the boiling of the coolant with high content of boron and considering low concentration of boric acid in the steam leaving the core, conditions may arise for the possible accumulation and subsequent crystallization of boric acid in the reactor that can lead to a deterioration of the process of core heat removal. To assess the chance of accumulation and subsequent crystallization of H3BO3 in the core of the WWER reactor, a hand calculation analysis of the change of concentration of boric acid in the reactor in case of emergency mode was carried out. In accordance with the calculation results, if a boric acid concentration in hydro accumulators of passive core cooling systems is 16 g / kg H2O, than a large excess of the final boric acid concentration in the core is observed in accidents after approximately 43 hours of an emergency process. The options of reducing the concentration of H3BO3 to 8, 4, 2 and 1 g/kg H2O are considered in the calculation process. The obtained results allow us to conclude that a decrease in the concentration of boric acid in the system of hydro accumulators of the third stage would allow to avoid the crystallization of boric acid in the core in the event of an accident.

High-Temperature Water-Based Mud Faces Challenges Offshore Sarawak, Malaysia

This article, written by Special Publications Editor Adam Wilson, contains highlights of paper OTC 28484, “Learnings From the High-Temperature Water-Based-Mud Application in Offshore Sarawak,” by M. Abshar M. Nor, SPE, M. Solehuddin A. Razak, and Lingges Devadass, Petronas, prepared for the 2018 Offshore Technology Conference Asia, Kuala Lumpur, 20–23 March. The paper has not been peer reviewed. Copyright 2018 Offshore Technology Conference. Reproduced by permission. The reservoir section of a gas field offshore Sarawak, Malaysia, consists of two massive pinnacle carbonate structures with heterogeneous porosity and permeability and many vugs and faults. Severe to total loss of circulation was expected along with a high bottomhole temperature (BHT). Considering the high risk of lost circulation, the drilling-fluid strategy involved designing and testing a high-temperature (HT) -tolerant water-based mud (WBM). While the main hole was drilled successfully with the HT WBM, the sidetrack experienced a significant reduction in rate of penetration (ROP). Well Design and Execution Challenges During the design stage, determination of the severity of losses in the carbonate formation was met with high uncertainty. Consequently, a WBM system was selected to drill the 8½-in. reservoir section. A shale formation was predicted to be above the carbonate section, and a 95/8-in. casing was planned to be set as close as possible at the top of the carbonate to isolate the shale. With the 95/8-in. casing in place, the WBM was to be used to drill the shoe track and the remaining small shale section before entering the carbonate reservoir. The BHT of the reservoir was predicted to be 370°F, which was extrapolated from data from offset wells. In addition, the pore pressure in the reservoir was overpressured approximately 14 lbm/gal because of a gas column in the carbonate. The high BHT coupled with the high mud-weight requirement of up to 14.5 lbm/gal led to the design of an unconventional HT WBM, which was a first for the operator. Special attention also was given to the corrosion risk on the drillstring from expected hydrogen sulfide levels up to 150 ppm and carbon dioxide levels up to 20% in the reservoir. Predrill Laboratory Study Laboratory tests were conducted to address major well challenges and overall performance of the system under extreme borehole temperatures. To ensure the mud system was able to withstand temperatures up to 400°F, a synthetic polymer was introduced to the mud design. Several mud formulations were tested and fine-tuned to achieve well-specific mud specifications for optimal hydraulic capability. Laboratory tests in accordance with American Petroleum Institute Recommended Practice 13B were conducted to evaluate the mud properties with various concentrations of additives. Four samples—Samples A, B, C, and D—were prepared and submitted to the same test procedure to understand the mud rheological behavior upon exposure to the HT environment.

Circulation conservation and vortex breakup in magnetohydrodynamics at low magnetic Prandtl number

In this paper we examine the role of weak magnetic fields in breaking Kelvin’s circulation theorem and in vortex breakup in two-dimensional magnetohydrodynamics for the physically important case of a fluid with low magnetic Prandtl number (low $Pm$ ). We consider three canonical inviscid solutions for the purely hydrodynamical problem, namely a Gaussian vortex, a circular vortex patch and an elliptical vortex patch. We examine how magnetic fields lead to an initial loss of circulation $\unicode[STIX]{x1D6E4}$ and attempt to derive scaling laws for the loss of circulation as a function of field strength and diffusion as measured by two non-dimensional parameters. We show that for all cases the loss of circulation depends on the integrated effects of the Lorentz force, with the patch cases leading to significantly greater circulation loss. For the case of the elliptical vortex, the loss of circulation depends on the total area swept out by the rotating vortex, and so this leads to more efficient circulation loss than for a circular vortex.

Potensi Scopoletin sebagai Agonis Reseptor Transferin 2 untuk Pengembangan Terapi Anemia Defisiensi Besi

<p><strong>Introduction</strong>: Iron Deficiency Anemia (IDA) is caused by imbalance between iron intake and iron loss in blood circulation. Increased hepcidin level plays an important role in the etiology of IDA. Normally, expression of hepcidin protein is controlled by three different pathways, one of them is interaction between holo Transferin (Holo-Tf) and Transferrin Receptor 2 (TfR-2). Recently, Indonesian herbal plants have widely been used as herbal medicine but there is no active compound that can activate TfR-2 for IDA therapy. The aim of this study was to explore phytochemicals derived from Indonesian herbal plants to interact with TfR-2.</p><p><strong>Methods: </strong>The study was a bioinformatics study with a molecular docking method. The SWISS-MODEL software was used to make TfR-2 protein modeling because the molecular structure of TfR-2 remains unknown. Holo-Tf was used as a standard ligand and obtained from Protein Data Bank with PDB ID 1SUV. All Indonesian phytochemicals which (1) registered at HerbalDB (2) had a three-dimensional molecular structure at PubChem (3) met Lipinski’s Rule of Five criteria were used in this study. AutoDock Vina 1.1.2 was used to analyze the binding affinity which was in kcal/mol. Phytochemical-TfR-2 binding complexes were visualized by using Chimera 1.10rc and or Pymol 1.7.</p><p><strong>Result: </strong>The docking scores of holo-Tf modification with TfR-2 were -6,4±0,1 kcal/mol at Arg466 and -3,4±0,1 kcal/mol at Arg689 respectively. Interaction of modification holo-Tf and TfR-2 was observed not only at Arg466 and Arg689 but also with Asp642 and Ile682. Docking scores of scopoletin were -7,1±0,1 kcal/mol at Arg466 and -5,4±0,1 kcal/mol at Arg689. Scopoletin could interact with TfR-2 at Arg466, Arg689, and Leu630 residues.</p><p><strong>Conclusions: </strong>Computationally, scopoletin is a potential TfR-2 agonist. In future studies, in vitro assay will be used to evaluate the agonist effect of scopoletin in TfR-2.</p><p> </p>

The Iceland Deep Drilling Project at Reykjanes: Drilling into the root zone of a black smoker analog

The aim of the Iceland Deep Drilling Project is to drill into supercritical geothermal systems and examine their economic potential. The exploratory well IDDP-2 was drilled in the Reykjanes geothermal field in SW Iceland, on the landward extension of the Mid-Atlantic Ridge. The Reykjanes geothermal field produces from a <300 °C reservoir at 1 to 2.5 km depth and is unusual because it is recharged by seawater. The well was cased to 3000 m depth, and then angled towards the main up-flow zone of the system, to a total slant depth of 4659 m (~4500 m vertical depth). Based on alteration mineral assemblages, joint inversion of wireline logging, and rate of heating measurements, the bottom hole temperature is estimated to be about 535 °C.The major problem encountered during drilling was the total loss of circulation below 3 km depth and continuing to the final depth. Drilling continued without recovering drill cuttings, consequently spot coring provided the only deep rock samples from the well. These cores are characteristic of a basaltic sheeted dike complex, with hydrothermal alteration mineral assemblages that range from greenschist to amphibolite facies, hornblende hornfels, and pyroxene hornfels, allowing the opportunity to investigate water-rock interaction in the active roots of an analog of a submarine hydrothermal system. As they have not yet been sampled, the composition of the deep fluids at Reykjanes is unknown at present. Cold water is currently being injected with the aim of enhancing permeability at depth, before allowing the well to heat up prior to flow tests planned for early 2019. The well has at least two fluid feed zones, a dominant one at 3.4 km depth and a second smaller one at 4.5 km.Extensive geophysical surveys of the Reykjanes Peninsula completed recently allow correlation of geophysical signals with rocks properties and in-situ conditions in the subsurface. Earthquake activity monitored with a local seismic network during drilling the IDDP-2 drilling detected abundant small earthquakes (ML ≤ 2) within the depth range of 3–5 km. A zone at 3–5 km depth below the producing geothermal field that was generally aseismic prior to drilling, but became seismically active during the drilling.The drilling of the IDDP-2 has achieved number of scientific and engineering firsts. It is the deepest and hottest drill hole so far sited on an active mid-ocean spreading center. It penetrated an active supercritical hydrothermal environment at depths analogous to those postulated as the high temperature reaction zones feeding black smoker systems.

Construction of nursing-sensitive quality indicators for haemodialysis using Delphi method.

To provide a set of nursing-sensitive quality indicators (NSQIs) for the evaluation of clinical nursing quality in haemodialysis unit. There are no established objective indicators for evaluation of the quality of nursing care in haemodialysis units in China. We performed a literature search for eligible studies published from 2006-2016. A total of six studies were screened out from which 13 potential NSQIs were identified. Two rounds of Delphi surveys were conducted with the purpose of collecting opinions from a panel of independent experts. At last, 11 NSQIs were selected by consensus after exclusion of 8 NSQIs and addition of another 6 NSQIs. Two rounds of expert inquiry were conducted; the questionnaire recovery rate was 100%. The average authoritative coefficients Cr for the two rounds were 0.79 and 0.90, respectively. The Kendall W values ranged from 0.273-0.388 (p<0.001). Eleven NSQIs were identified: nurse-to-patient ratio, dialysis ultrafiltration rate compliance rate, KT/V compliance rate, incidence of emergency during haemodialysis, person-time incidence rate of haemodialysis catheter-related bloodstream infections, incidence of coagulation in extracorporeal circulation, incidence of blood loss in extracorporeal circulation, incidence of pseudoaneurysm induced by fistula puncture, incidence of falls among haemodialysis patients, emergency dialysis rate of outpatients and incidence of fistula complications. The identified NSQIs reflect three aspects of haemodialysis nursing quality: importance, rationality of calculation formula and applicability of data collection methods. The study provides a reference for the evaluation of clinical nursing quality in haemodialysis units.

The journalism of Gannett Blog: Revealing communities of practice and social construction through collective dynamics

Abstract Gannett Company was one of the largest media operations in the United States but struggled in recent years with loss of revenue and circulation. Gannett Blog reported news related to the company from 2007 to 2014. The blog was independent and covered corporate news, job loss and issues of ethics. This used Gannett Blog to study how individuals reacted to their changing workplace. As information was gathered and presented from multiple users, a crowdsourcing dynamic gave context to Gannett’s landscape. Theories of communities of practice and social construction underpin this study. This study suggests that the rhetoric on Gannett Blog evolved into more than a distribution channel for information. It became a social space where original information evolved and helped negotiate social meaning for the users. Overall, this study found that communities of professionals could be influential in growing a journalistic product as per the tenets of the communities of influence model. This study also identified themes consistent with news workers using Gannett Blog for community building, expanding knowledge and maintaining professionalism during industry change.

Osteonecrosis

Formerly referred to as avascular necrosis, the term osteonecrosis is now preferred. Simply defined, osteonecrosis means ‘dead bone’. The ‘avascular’ state of the necrotic bone is the result of a loss of circulation from numerous potential causes together with multiple risk factors. The resultant state is a sequelae of repair processes leading finally to gross deformation of the bony structural architecture and joint incongruity. Among the commonest sites are the femoral head, talus, lunate, knee and humeral head. In addition to normal radiography, bone scan and MRI have provided early diagnosis of subtle changes in the osteo-histology. Intervention depends upon the phase of disease progression; in the form of a series of preservation and/or salvage procedures.

Entry of online presale of fresh produce: A competitive analysis

The fresh produce market is one of the last unexplored spaces for e-commerce and has attracted the entrance of many e-commerce firms in recent years; these firms are likely to influence the traditional fresh produce sales channels. The online presale of fresh produce can lower the circulation loss rate while traditional sales channels suffer from a huge waste in the circulation. In this paper, we study the online presale model of fresh produce from a competitive perspective. We examine the pricing and order decisions of one online grocery and one physical store. By examining the physical store with and without the online grocery, we investigate the impact of the entry of an online grocery on the physical store. We first identify two pricing strategies, penetration-pricing and skimming-pricing, for the physical store and two pricing strategies for the online grocery, and then identify the conditions under which pricing equilibrium will occur. We find that the store does not necessarily alter its pricing strategy after the online grocery enters the market. When the physical store uses the penetration-pricing strategy to compete with the online grocery for Internet shoppers, it may fail to achieve that goal if the online grocery's delivery cost is low and if the Internet shoppers account for a relatively low proportion of shoppers. Alternatively, the physical store may fail if the online grocery's delivery cost is not high and if the circulation loss rate of fresh produce is high.

Theory calculation and testing of air injection parameters in ice core drilling with air reverse circulation

Drilling with air reverse circulation is considered one of the most promising technologies in ice core drilling, especially in firn-ice drilling, as it has many advantages in preventing air circulation loss, improving stability of the borehole, and promoting penetration rate. The effectiveness of this technology depends on whether or not the ice chips and cores can be conveyed to the surface through the central channel of the drill tool. In order to determine the adequate volume flow rate of the gas needed to satisfy the demand for continuous return of the ice cores and chips, a mathematical model to evaluate the injection pressure was studied. A series of experiments were carried out to test the actual air velocity required to move ice cores and ice chips with different sizes and clearances between the ice cores and the inner wall of the pipe. Based on the calculation and testing results, the minimum air volume requirements with different borehole depths in ice core drilling with air reverse circulation were confirmed. For a borehole with depth of 1000 m and diameter of 134 mm, the volume flow rate and pressure of air under standard atmosphere condition are at least 6.27 m3/min and 0.70 MPa to transport ice chips and ice cores with diameter of 60 mm and length of 250 mm.

On the global dynamic behaviour for a generalized haematopoiesis model with almost periodic coefficients and oscillating circulation loss rate

A generalized non‐linear nonautonomous model for the haematopoiesis (cell production) with several delays and an oscillating circulation loss rate is studied. We prove a fixed point theorem in abstract cones, from which different results on existence and uniqueness of positive almost periodic solutions are deduced. Moreover, some criteria are given to guarantee that the obtained positive almost periodic solution is globally exponentially stable.

From global circulation to local flood loss: Coupling models across the scales

Comprehensive flood risk modeling is crucial for understanding, assessing, and mitigating flood risk. Modeling extreme events is a well-established practice in the atmospheric and hydrological sciences and in the insurance industry. Several specialized models are used to research extreme events including atmospheric circulation models, hydrological models, hydrodynamic models, and damage and loss models. Although these model types are well established, and coupling two to three of these models has been successful, no assessment of a full and comprehensive model chain from the atmospheric to local scale flood loss models has been conducted. The present study introduces a model chain setup incorporating a GCM/RCM to model atmospheric processes, a hydrological model to estimate the catchment's runoff reaction to precipitation inputs, a hydrodynamic model to identify flood-affected areas, and a damage and loss model to estimate flood losses. Such coupling requires building interfaces between the individual models that are coherent in terms of spatial and temporal resolution and therefore calls for several pre- and post-processing steps for the individual models as well as for a computationally efficient strategy to identify and model extreme events. The results show that a coupled model chain allows for good representation of runoff for both long-term runoff characteristics and extreme events, provided a bias correction on precipitation input is applied. While the presented approach for deriving loss estimations for particular extreme events leads to reasonable results, two issues have been identified that need to be considered in further applications: (i) the identification of extreme events in long-term GCM simulations for downscaling and (ii) the representativeness of the vulnerability functions for local conditions.

Experimental examination of vorticity stripping from a wing-tip vortex in free-stream turbulence

Circulation loss from a vortex immersed in turbulent surroundings occurs in a nondiffusive manner. Experiments are used to connect the circulation loss to instantaneous instances of vorticity stripping from the vortex core.