Sensitivity of EEHG simulations to dynamic beam parameters Samoilenko, D; Hillert, W; Pannek, F ...
13th International Particle Accelerator Conference, IPAC 2022,Bangkok, Thailand,2022-06-12 - 2022-06-17,
01/2023, Letnik:
2420, Številka:
1
Journal Article, Conference Proceeding
Recenzirano
Odprti dostop
Abstract
Currently, the Free electron laser user facility FLASH at DESY is undergoing a significant upgrade involving the complete transformation of one of its beamlines to allow external seeding. ...With the Echo-Enabled Harmonic Generation (EEHG) seeding method, we aim for the generation of fully coherent XUV and soft X-ray pulses at wavelengths down to 4 nm. The generated FEL radiation is sensitive to various electron beam properties, e.g., its energy profile imprinted either deliberately or by collective effects such as Coherent Synchrotron Radiation (CSR). In dedicated particle tracking simulations, one usually makes certain assumptions concerning the beam properties and the collective effects to simplify implementation and analysis. Here, we estimate the influence of some of the common assumptions made in EEHG simulations on the properties of the output FEL radiation, using the example of FLASH and its proposed seeding beamline. We conclude that the inherent properties of the FLASH1 beam, namely the negatively chirped energy profile, has dominant effect on the spectral intensity profile of the radiators output compare to that of the CSR induced chirp.
The FLASHForward facility at DESY Aschikhin, A.; Behrens, C.; Bohlen, S. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
01/2016, Letnik:
806
Journal Article
Recenzirano
Odprti dostop
The FLASHForward project at DESY is a pioneering plasma-wakefield acceleration experiment that aims to produce, in a few centimetres of ionised hydrogen, beams with energy of order GeV that are of ...quality sufficient to be used in a free-electron laser. The plasma is created by ionising a gas in a gas cell with a multi-TW laser system. The plasma wave will be driven by high-current-density electron beams from the FLASH linear accelerator. The laser system can also be used to provide optical diagnostics of the plasma and electron beams due to the <30fs synchronisation between the laser and the driving electron beam. The project will explore both external and internal witness-beam injection techniques. The operation parameters of the experiment are discussed, as well as the scientific programme.
The FLASHForward project at DESY is a pioneering plasma-wakefield acceleration experiment that aims to produce, in a few centimetres of ionised hydrogen, beams with energy of order GeV that are of ...quality sufficient to be used in a free-electron laser. The plasma wave will be driven by high-current density electron beams from the FLASH linear accelerator and will explore both external and internal witness-beam injection techniques. The plasma is created by ionising a gas in a gas cell with a multi-TW laser system, which can also be used to provide optical diagnostics of the plasma and electron beams due to the <30 fs synchronisation between the laser and the driving electron beam. The operation parameters of the experiment are discussed, as well as the scientific program.
Temporal lobe epilepsy (TLE) accompanied by hippocampal sclerosis (HS) is the type of epilepsy most frequently operated on. The predictors for long-term seizure freedom after surgery of TLE-HS are ...unknown. In this study, we aimed to identify prognostic factors which predict the outcome 6 months and 2, 3 and 5 years after epilepsy surgery of TLE-HS. Our working hypothesis was that the prognostic value of potential predictors depended on the post-operative time interval for which the assessment was made. We included 171 patients (100 females and 71 males, aged 16–59 years) who had undergone presurgical evaluation, including video-EEG, who had had MRI-defined HS, and who had undergone temporal lobectomy. We found that secondarily generalized seizures (SGTCS) and ictal dystonia were associated with a worse 2-year outcome. Both these variables together with older age and longer epilepsy duration were also related to a worse 3-year outcome. Ictal limb dystonia, older age and longer epilepsy duration were associated with long-term surgical failure evaluated 5 years post-operatively. In order to determine the independent predictors of outcomes, we calculated multivariate analyses. The presence of SGTCS and ictal dystonia independently predicted the 2-year outcome. Longer epilepsy duration and ictal dystonia predicted the 3-year outcome. Longer epilepsy duration (P = 0.003) predicted a poor 5-year outcome. Conclusively, predictors for the long-term surgical results of TLE with HS are different from those variables that predict the short-term outcome. Epilepsy duration is the most important predictor for long-term surgical outcome. Our results strongly suggest that surgery for TLE-HS should be performed as early as possible.
Aims
To systematically evaluate effectiveness and safety of bladder augmentation for adult neuro‐urological patients.
Methods
The Preferred Reporting Items for Systematic Review and Meta‐analysis ...(PRISMA) statement was followed for review of publications. The Medline, Embase, and Cochrane controlled trial databases and clinicaltrial.gov were searched until January 2015. No limitations were placed on date or language. Non‐original articles, conference s, and publications involving children and animals were excluded. Risk‐of‐bias and confounder assessment was performed.
Results
A total of 20 studies including 511 patients were eligible for inclusion. The level of evidence for the included studies was low, most level 4 studies with only one level 3 study. The data were narratively synthesized. Across all studies high risk‐of bias and confounding was found. Primary outcomes were assessed in 16 of the 20 studies and showed improved quality of life and anatomical changes as well as stable renal function. The secondary outcomes were reported in 17 of the 20 studies and urodynamic parameters and continence all demonstrated improvement after bladder reconstruction. Long‐term complications continued up to 10 years post‐operatively, including bowel dysfunction in 15% of the patients, stone formation in 10%, five bladder perforations and one bladder cancer.
Conclusions
Available studies are not plentiful and of relatively poor quality, appropriately designed prospective studies are urgently needed. Despite this, bladder augmentation appears to be a highly effective procedure at protecting the upper urinary tract and improving quality of life. However, it is associated with relatively high morbidity in both the short and long term.
Objectives: To identify predictive factors for the seizure-free outcome of vagus nerve stimulation (VNS). Methods: All 47 patients who had undergone VNS implantation at one centre and had at least ...one year of follow up were studied. They underwent complete presurgical evaluation including detailed clinical history, magnetic resonance imaging, and long term video-EEG with ictal and interictal recordings. After implantation, adjustment of stimulation parameters and concomitant antiepileptic drugs were at the discretion of the treating physician. Results: Mean (SD) age of the patients was 22.7 (11.6) years (range 7 to 53). Six patients (13%) became seizure-free after the VNS implantation. Only two variables showed a significant association with the seizure-free outcome: absence of bilateral interictal epileptiform discharges (IED) and presence of malformation of cortical development (MCD). Epilepsy duration showed a non-significant trend towards a negative association with outcome. By logistic regression analysis, only absence of bilateral IED correlated independently with successful VNS treatment (p<0.01, odds ratio = 29.2 (95% confidence interval, 2.4 to 353)). Bilateral IED (independent or bilateral synchronous) was found in one of six seizure-free patients and in 33 of 41 non-seizure-free patients. When bilateral IED were absent, the sensitivity for seizure-free outcome was 0.83 (0.44 to 0.97), and the specificity was 0.80 (0.66 to 0.90). Conclusions: Bilateral IED was independently associated with the outcome of VNS. These results are preliminary because they were based on a small patient population. They may facilitate prospective VNS studies enrolling larger numbers of patients to confirm the results.
The updated 2024 European Association of Urology neurourology guidelines highlight the importance of a tailored, comprehensive approach for management of neurourological disorders. Patient outcomes ...can be improved by addressing individual needs, including urodynamics and lifestyle considerations via a multidisciplinary strategy. The guidelines cover the latest evidence and treatments to support patients in maintaining their quality of life across all facets of neurological impact.
Most patients with neurourological disorders require lifelong medical care. The European Association of Urology (EAU) regularly updates guidelines for diagnosis and treatment of these patients. The objective of this review is to provide a summary of the 2024 updated EAU guidelines on neurourology.
A structured literature review covering the timeframe 2021–2023 was conducted for the guideline update. A level of evidence and a strength rating were assigned for each recommendation on the basis of the literature data.
Neurological conditions significantly affect urinary, sexual, and bowel function, and lifelong management is required for neurourological patients to maintain their quality of life and prevent urinary tract deterioration. Early diagnosis and effective treatment are key, and comprehensive clinical assessments, including urodynamics, are crucial. Management should be customised to individual needs and should involve a multidisciplinary approach and address sexuality and fertility. Lifelong monitoring and follow-up highlight the importance of continuous care for neurourological patients.
The 2024 EAU guidelines on neurourology provide an up-to-date overview of available evidence on diagnosis, treatment, and follow-up for neurourological patients.
Neurological disorders very frequently affect the lower urinary tract and sexual and bowel function and patients need lifelong management. We summarise the updated European Association of Urology guidelines on neurourology to provide patients and caregivers with the latest insights for optimal health care support.
Purpose: The mechanisms of drug resistance in epilepsy are only incompletely understood. According to a current concept, overexpression of drug efflux transporters at the blood–brain barrier may ...reduce levels of antiepileptic drugs (AEDs) in epileptogenic brain tissue. Increased expression of drug efflux transporters such as P‐glycoprotein has been found in brain tissue surgically resected from patients with medically intractable epilepsy, but it is not known whether this leads to decreased extracellular (interstitial) AED concentrations in affected brain regions. This prompted us to measure concentrations of AEDs in the extracellular space of human neocortical tissue by using intraoperative microdialysis (IOMD) in those parts of the brain that had to be removed for therapeutic reasons. For comparison, AED levels were determined in brain tissue, subarachnoid CSF, and serum.
Methods: Concentrations of carbamazepine (CBZ), 10‐hydroxy‐carbazepine (10‐OH‐CZ, metabolite of oxcarbazepine), lamotrigine (LTG), levetiracetam (LEV), topiramate, or phenytoin were determined by using one to four catheters during IOMD in the medial temporal gyrus. Furthermore, to calculate the individual recovery of every catheter, an in vitro microdialysis was performed with ultrafiltrate of serum concurrently obtained from the respective patient. In addition, AED levels were determined in the resected brain tissue, CSF, and serum of the same patients. Altogether 22 pharmacoresistant epilepsy patients (nine male, 13 female patients; age 15–54 years) with complex partial seizures or secondarily generalized seizures were involved. In a first series, IOMD samples 40 min after beginning of the microdialysis (flow rate, 1 μl/min), and in a second series, continuous measurements 25, 30, 35, and 40 min from the beginning were evaluated (flow rate, 2 μl/min). With in vitro recovery data of the individual catheters, the concentration in the extracellular space (ECS) was estimated.
Results: AED concentrations in the ECS of the cortex measured by catheters located at a distance of 0.6 cm differed markedly in some patients, whereas concentrations in the ultrafiltrate of the serum of the respective patients measured with the same catheters varied only slightly. Furthermore, ECS concentrations related to the ultrafiltrate of serum showed considerable interindividual variations. The high intra‐ and interindividual variation of ECS concentrations is demonstrated by the low correlation between concentrations in ECS and the ultrafiltrate of serum (CBZ, r= 0.41; 10‐OH‐CZ, r= 0.42; LTG, r= 0.27) in contrast to the high correlation between brain tissue concentration and the ultrafiltrate of serum (CBZ, r= 0.97; 10‐OH‐CZ, r= 0.88; LTG, r= 0.98) in the same group of patients. When comparing AED concentrations in the ECS with those in the CSF, ECS concentrations were significantly lower for CBZ, 10‐OH‐CZ, LTG, and LEV.
Conclusions: The data demonstrate that AED concentrations show a considerable intraindividual and interindividual variation in the ECS of cortical regions. Furthermore, the ECS concentration of several AEDs is significantly lower than their CSF concentration in patients with intractable epilepsy. However, in the absence of data from nonepileptic tissues, it is not possible to judge whether the present findings relate to overexpression of multidrug transporters in the brain. Instead, the present study illustrates the methodologic difficulties involved in performing IOMD studies in patients and may thus be helpful for future approaches aimed at elucidating the role of multidrug transporters in epilepsy.
Abstract Context Tibial nerve stimulation (TNS) is a promising therapy for non-neurogenic lower urinary tract dysfunction and might also be a valuable option for patients with an underlying ...neurological disorder. Objective We systematically reviewed all available evidence on the efficacy and safety of TNS for treating neurogenic lower urinary tract dysfunction (NLUTD). Evidence acquisition The review was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Statement. Evidence synthesis After screening 1943 articles, 16 studies (4 randomized controlled trials RCTs, 9 prospective cohort studies, 2 retrospective case series, and 1 case report) enrolling 469 patients (283 women and 186 men) were included. Five studies reported on acute TNS and 11 on chronic TNS. In acute and chronic TNS, the mean increase of maximum cystometric capacity ranged from 56 to 132 mL and from 49 to 150 mL, and the mean increase of bladder volume at first detrusor overactivity ranged from 44 to 92 mL and from 93 to 121 mL, respectively. In acute and chronic TNS, the mean decrease of maximum detrusor pressure during the storage phase ranged from 5 to 15 cm H2 O and from 4 to 21 cm H2 O, respectively. In chronic TNS, the mean decrease in number of voids per 24 h, in number of leakages per 24 h, and in postvoid residual ranged from 3 to 7, from 1 to 4, and from 15 to 55 mL, respectively. No TNS-related adverse events have been reported. Risk of bias and confounding was high in most studies. Conclusions Although preliminary data of RCTs and non-RCTs suggest TNS might be effective and safe for treating NLUTD, the evidence base is poor, derived from small, mostly noncomparative studies with a high risk of bias and confounding. More reliable data from well-designed RCTs are needed to reach definitive conclusions. Patient summary Early data suggest tibial nerve stimulation might be effective and safe for treating neurogenic lower urinary tract dysfunction, but more reliable evidence is required.
To develop an International Spinal Cord Injury (SCI) Urinary Tract Infection (UTI) Basic Data Set presenting a standardized format for the collection and reporting of a minimal amount of information ...on UTIs in daily practice or research.
International working group.
The draft of the Data Set developed by a working group was reviewed by the Executive Committee of the International SCI Standards and Data Sets, and later by the International Spinal Cord Society (ISCoS) Scientific Committee and the American Spinal Injury Association (ASIA) Board. Relevant and interested scientific and professional (international) organizations and societies (∼40) were also invited to review the data set, and it was posted on the ISCoS and ASIA websites for 3 months to allow comments and suggestions. The ISCoS Scientific Committee, Executive Committee and ASIA Board received the data set for final review and approval.
The International SCI UTI Basic Data Set includes the following variables: date of data collection, length of time of sign(s)/symptom(s), results of urine dipstick test for nitrite and leukocyte esterase, urine culture results and resistance pattern. The complete instructions for data collection and the data form itself are freely available on the website of ISCoS (http://www.iscos.org.uk).
PDF
