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1.
BMC Health Serv Res ; 23(1): 1095, 2023 Oct 12.
Article En | MEDLINE | ID: mdl-37828553

INTRODUCTION: Effective leadership and management (L&M) are essential to the success of health care organizations. Young medical leaders often find themselves ill-prepared to take on these new responsibilities, but rarely attend training in L&M skills. The aims of this study were to evaluate physician's self-perceived competencies and training needs for L&M, to identify available regional L&M training, and to highlight opportunities, challenges and threats regarding physicians' training in medical L&M in the French-speaking part of Switzerland. METHODS: We conducted a mixed methods study in three steps: (1) a survey on perceived L&M competencies and training needs (5 dimensions) to all physicians of a Swiss University Hospital (N = 2247); (2) a mapping of the Swiss French speaking L&M training programs through analysis of hospital websites and interviews; and (3) semi-structured interviews with L&M program coordinators about the programs' strengths and weaknesses as well as the opportunities and challenges to include physicians in such training. We used analysis of variance to compare differences in perceived competences between physicians of different hierarchical status and used Cramer's V to measure the association's degree between physicians' training needs and prior training in L&M and hierarchical status. We analysed semi-structured interviews using thematic analysis. RESULTS: Five-hundred thirty-two physicians responded (24%). Physicians perceived themselves as rather competent in most leadership dimensions. More experienced physicians reported a higher sense of competence in all dimensions of leadership (e.g. Working with others: F = 15.55, p < .001; Managing services: F = 46.89, p < .001). Three competencies did not vary according to the hierarchical status: emotional intelligence (F = 1.56, p = .20), time management (F = 0.47, p = .70) and communicating (F = 1.97, p = .12). There was a weak to moderate association between the responders' self-perceived needs for training and their hierarchal status for all competencies (Cramer's V ∈ [0.16;0.35]). Physicians expressed a strong desire to seek out training for all competencies, especially for knowing one's leadership style (82%), managing teams (83%), and managing conflict (85%). Although existing local L&M training programs covered most relevant topics, only a forth of responders had attended any type of training. L&M program coordinators identified several facilitators and barriers to physician attendance on institutional (matching reality and training), relational (managing collective intelligence), and individual levels (beliefs and self-perceived identity). CONCLUSIONS: French-speaking Swiss hospital physicians clearly express training needs for L&M skills although they only rarely attend such training programs. Reasons for non-attendance to such programs should be explored in order to understand physicians' low participation rates in these trainings.


Leadership , Physicians , Humans , Switzerland , Professional Competence , Clinical Competence
2.
Phys Rev Lett ; 129(2): 024802, 2022 Jul 08.
Article En | MEDLINE | ID: mdl-35867433

A long, narrow, relativistic charged particle bunch propagating in plasma is subject to the self-modulation (SM) instability. We show that SM of a proton bunch can be seeded by the wakefields driven by a preceding electron bunch. SM timing reproducibility and control are at the level of a small fraction of the modulation period. With this seeding method, we independently control the amplitude of the seed wakefields with the charge of the electron bunch and the growth rate of SM with the charge of the proton bunch. Seeding leads to larger growth of the wakefields than in the instability case.

3.
Phys Rev Lett ; 126(16): 164802, 2021 Apr 23.
Article En | MEDLINE | ID: mdl-33961468

We use a relativistic ionization front to provide various initial transverse wakefield amplitudes for the self-modulation of a long proton bunch in plasma. We show experimentally that, with sufficient initial amplitude [≥(4.1±0.4) MV/m], the phase of the modulation along the bunch is reproducible from event to event, with 3%-7% (of 2π) rms variations all along the bunch. The phase is not reproducible for lower initial amplitudes. We observe the transition between these two regimes. Phase reproducibility is essential for deterministic external injection of particles to be accelerated.

4.
Phys Rev Lett ; 125(26): 264801, 2020 Dec 31.
Article En | MEDLINE | ID: mdl-33449727

We study experimentally the effect of linear plasma density gradients on the self-modulation of a 400 GeV proton bunch. Results show that a positive or negative gradient increases or decreases the number of microbunches and the relative charge per microbunch observed after 10 m of plasma. The measured modulation frequency also increases or decreases. With the largest positive gradient we observe two frequencies in the modulation power spectrum. Results are consistent with changes in wakefields' phase velocity due to plasma density gradients adding to the slow wakefields' phase velocity during self-modulation growth predicted by linear theory.

6.
Philos Trans A Math Phys Eng Sci ; 377(2151): 20180418, 2019 Aug 12.
Article En | MEDLINE | ID: mdl-31230571

In this article, we briefly summarize the experiments performed during the first run of the Advanced Wakefield Experiment, AWAKE, at CERN (European Organization for Nuclear Research). The final goal of AWAKE Run 1 (2013-2018) was to demonstrate that 10-20 MeV electrons can be accelerated to GeV energies in a plasma wakefield driven by a highly relativistic self-modulated proton bunch. We describe the experiment, outline the measurement concept and present first results. Last, we outline our plans for the future. This article is part of the Theo Murphy meeting issue 'Directions in particle beam-driven plasma wakefield acceleration'.

7.
Phys Rev Lett ; 122(5): 054802, 2019 Feb 08.
Article En | MEDLINE | ID: mdl-30822008

We give direct experimental evidence for the observation of the full transverse self-modulation of a long, relativistic proton bunch propagating through a dense plasma. The bunch exits the plasma with a periodic density modulation resulting from radial wakefield effects. We show that the modulation is seeded by a relativistic ionization front created using an intense laser pulse copropagating with the proton bunch. The modulation extends over the length of the proton bunch following the seed point. By varying the plasma density over one order of magnitude, we show that the modulation frequency scales with the expected dependence on the plasma density, i.e., it is equal to the plasma frequency, as expected from theory.

8.
Phys Rev Lett ; 122(5): 054801, 2019 Feb 08.
Article En | MEDLINE | ID: mdl-30822039

We measure the effects of transverse wakefields driven by a relativistic proton bunch in plasma with densities of 2.1×10^{14} and 7.7×10^{14} electrons/cm^{3}. We show that these wakefields periodically defocus the proton bunch itself, consistently with the development of the seeded self-modulation process. We show that the defocusing increases both along the bunch and along the plasma by using time resolved and time-integrated measurements of the proton bunch transverse distribution. We evaluate the transverse wakefield amplitudes and show that they exceed their seed value (<15 MV/m) and reach over 300 MV/m. All these results confirm the development of the seeded self-modulation process, a necessary condition for external injection of low energy and acceleration of electrons to multi-GeV energy levels.

9.
World J Urol ; 37(7): 1369-1375, 2019 Jul.
Article En | MEDLINE | ID: mdl-30288598

PURPOSE: Aquablation of the prostate using the AquaBeam™ system promises equivalent functional outcomes, reduced learning curve, and improved sexual function compared to transurethral prostate resection as shown in prospective randomized trials. This prospective cohort study aims to evaluate if published results can be transferred into the clinical routine in a non-selected patient collective. METHODS: This study includes all patients treated between September 2017 and June 2018 with Aquablation of the prostate. Patients have been evaluated prospectively for the perioperative course and early follow-up. Besides voiding parameter and symptom score, TRUS-volume change, ejaculatory function, and adverse events have been recorded. RESULTS: 118 consecutive patients have been treated in the given time. Aquablation could be carried out successfully in all patients. IPSS, QoL, Qmax, and PVR improved significantly after the procedure and continued to improve during 3-month follow-up. Mean OR time was 20 min, TRUS volume decreased by 65%, and 73% of the patients retained antegrade ejaculation. Thirteen adverse events (> Clavien-Dindo I) occurred in 10 patients. CONCLUSION: The surgical ablation of the prostate using Aquablation achieved significant and immediate improvement of functional voiding parameters Qmax and PVR as well as symptomatic improvement of IPSS and QoL. Aquablation seems to be safe and effective with a low perioperative complication profile even in a non-selected group of patients.


Ablation Techniques/methods , Prostatic Hyperplasia/surgery , Transurethral Resection of Prostate/methods , Urethral Obstruction/surgery , Water , Aged , Aged, 80 and over , Cohort Studies , Humans , Male , Middle Aged , Postoperative Complications/epidemiology , Prostatic Hyperplasia/complications , Sexual Dysfunction, Physiological/epidemiology , Treatment Outcome , Urethral Obstruction/etiology
10.
Nature ; 561(7723): 363-367, 2018 09.
Article En | MEDLINE | ID: mdl-30188496

High-energy particle accelerators have been crucial in providing a deeper understanding of fundamental particles and the forces that govern their interactions. To increase the energy of the particles or to reduce the size of the accelerator, new acceleration schemes need to be developed. Plasma wakefield acceleration1-5, in which the electrons in a plasma are excited, leading to strong electric fields (so called 'wakefields'), is one such promising acceleration technique. Experiments have shown that an intense laser pulse6-9 or electron bunch10,11 traversing a plasma can drive electric fields of tens of gigavolts per metre and above-well beyond those achieved in conventional radio-frequency accelerators (about 0.1 gigavolt per metre). However, the low stored energy of laser pulses and electron bunches means that multiple acceleration stages are needed to reach very high particle energies5,12. The use of proton bunches is compelling because they have the potential to drive wakefields and to accelerate electrons to high energy in a single acceleration stage13. Long, thin proton bunches can be used because they undergo a process called self-modulation14-16, a particle-plasma interaction that splits the bunch longitudinally into a series of high-density microbunches, which then act resonantly to create large wakefields. The Advanced Wakefield (AWAKE) experiment at CERN17-19 uses high-intensity proton bunches-in which each proton has an energy of 400 gigaelectronvolts, resulting in a total bunch energy of 19 kilojoules-to drive a wakefield in a ten-metre-long plasma. Electron bunches are then injected into this wakefield. Here we present measurements of electrons accelerated up to two gigaelectronvolts at the AWAKE experiment, in a demonstration of proton-driven plasma wakefield acceleration. Measurements were conducted under various plasma conditions and the acceleration was found to be consistent and reliable. The potential for this scheme to produce very high-energy electron bunches in a single accelerating stage20 means that our results are an important step towards the development of future high-energy particle accelerators21,22.

11.
Urologe A ; 57(4): 463-473, 2018 Apr.
Article De | MEDLINE | ID: mdl-29520419

Interventional treatment of stones essentially consists of three treatment modalities. Extracorporeal shockwave lithotripsy (ESWL), in addition to uterorenoscopy (URS) and percutaneous nephrolitholapaxy (PCNL) is an essential treatment pillar and is the only noninvasive therapy option for the treatment of urinary stones. After a long period of ESWL being the leading choice in stone treatment, the number of SWL interventions diminished in recent years in favor of the other two treatment modalities (URS and PCNL). This article describes the indications, surgical technique and management of complications of SWL.


Kidney Calculi/therapy , Lithotripsy/methods , Antibiotic Prophylaxis , Contraindications , Female , Humans , Male , Minimally Invasive Surgical Procedures , Nephrolithotomy, Percutaneous , Ureteroscopy
12.
Urologe A ; 56(9): 1193-1206, 2017 Sep.
Article De | MEDLINE | ID: mdl-28762032

Correct positioning of patients during preoperative preparations is essential for success of the intervention to avoid any positioning trauma and to provide the best access to the targeted structures. The appropriate positioning (and optimal performance) means that complications are avoided and also makes an essential contribution to the smooth course of the surgical intervention. A correct position is essential particularly in urology because the organs assigned to the discipline of urology are anatomically mostly difficult to reach. A further important function of the correct positioning technique is the avoidance of injuries to the patient. This article summarizes the most common positioning techniques in urological interventions with special emphasis on the explanation of practical advice, helpful tips and possible complications that can enable even junior surgeons to correctly perform the appropriate positioning technique.


Patient Positioning/methods , Urologic Diseases/surgery , Urologic Surgical Procedures/methods , Equipment Design , Female , Humans , Intraoperative Complications/prevention & control , Male , Operating Tables , Patient Positioning/instrumentation , Postoperative Complications/prevention & control , Preoperative Care/methods
13.
J Microsc ; 266(2): 115-125, 2017 05.
Article En | MEDLINE | ID: mdl-28267878

The mechanical cell environment is a key regulator of biological processes . In living tissues, cells are embedded into the 3D extracellular matrix and permanently exposed to mechanical forces. Quantification of the cellular strain state in a 3D matrix is therefore the first step towards understanding how physical cues determine single cell and multicellular behaviour. The majority of cell assays are, however, based on 2D cell cultures that lack many essential features of the in vivo cellular environment. Furthermore, nondestructive measurement of substrate and cellular mechanics requires appropriate computational tools for microscopic image analysis and interpretation. Here, we present an experimental and computational framework for generation and quantification of the cellular strain state in 3D cell cultures using a combination of 3D substrate stretcher, multichannel microscopic imaging and computational image analysis. The 3D substrate stretcher enables deformation of living cells embedded in bead-labelled 3D collagen hydrogels. Local substrate and cell deformations are determined by tracking displacement of fluorescent beads with subsequent finite element interpolation of cell strains over a tetrahedral tessellation. In this feasibility study, we debate diverse aspects of deformable 3D culture construction, quantification and evaluation, and present an example of its application for quantitative analysis of a cellular model system based on primary mouse hepatocytes undergoing transforming growth factor (TGF-ß) induced epithelial-to-mesenchymal transition.


Cell Culture Techniques/methods , Hepatocytes/cytology , Hepatocytes/physiology , Imaging, Three-Dimensional/methods , Microscopy/methods , Stress, Mechanical , Animals , Epithelial-Mesenchymal Transition , Hydrogel, Polyethylene Glycol Dimethacrylate , Mice
14.
Urologe A ; 56(3): 395-404, 2017 Mar.
Article De | MEDLINE | ID: mdl-28243769

Ureterorenoscopy (URS) is a minimally invasive treatment option for removal of kidney stones, which has gained importance in this field over the past two decades. This technique has replaced extracorporeal shock wave lithotripsy (ESWL) stone surgery for many indications. It is also particularly important in the diagnostics and treatment for tumors of the upper urinary tract. This article describes the indications, surgical technique and management of complications of URS.


Kidney Calculi/pathology , Kidney Calculi/surgery , Minimally Invasive Surgical Procedures/methods , Ureteroscopy/methods , Urologic Neoplasms/pathology , Urologic Neoplasms/surgery , Evidence-Based Medicine , Humans , Minimally Invasive Surgical Procedures/instrumentation , Treatment Outcome , Ureteroscopy/adverse effects , Ureteroscopy/instrumentation
16.
PLoS One ; 11(11): e0165233, 2016.
Article En | MEDLINE | ID: mdl-27855166

BACKGROUND: Induction treatment with rabbit polyclonal antithymocyte globulins (ATGs) is frequent used in kidney transplant recipients with donorspecific HLA antibodies and shows acceptable outcomes. The two commonly used ATGs, Thymoglobulin and ATG-F have slightly different antigen profile and antibody concentrations. The two compounds have never been directly compared in a prospective trial in immunological high-risk recipients. Therefore we performed a prospective randomized controlled study comparing the two compounds in immunological high-risk kidney recipients in terms of safety and efficacy. METHODS: Immunological high-risk kidney recipients, defined as the presence of HLA DSA but negative CDC-B and T-cell crossmatches were randomized 1:1 to receive ATG-F or Thymoglobulin. Maintenance immunosuppressive therapy consisted of tacrolimus, mycophenolate mofetil and steroids. RESULTS: The per-protocol analysis included 35 patients. There was no immediate infusion reaction observed with both compounds. No PTLD or malignancy occurred during the follow-up in both groups. The incidence of viral and bacterial infections was similar in both groups (p = 0.62). The cumulative incidence of clinical and subclinical antibody mediated allograft rejection as well as T-cell mediated allograft rejection during the first year between ATG-F and Thymoglobulin was similar (35% versus 19%; p = 0.30 and 11% versus 18%; 0.54 respectively). The two-year graft function was similar with a median eGFR of 56 ml/min/1.73m2 (range 21-128) (ATG-F-group) and 51 ml/min/1.73m2 (range 22-132) (Thymo-group) (p = 0.69). CONCLUSION: We found no significant differences between the compared study drugs for induction treatment in immunological high-risk patients regarding safety and efficacy during follow-up with good allograft function at 2 years after transplantation.


Antilymphocyte Serum/therapeutic use , Graft Rejection/prevention & control , Immunosuppressive Agents/therapeutic use , Kidney Transplantation , Transplant Recipients , Adult , Aged , Animals , Antilymphocyte Serum/adverse effects , Female , Graft Rejection/diagnosis , Graft Rejection/immunology , Graft Survival , HLA Antigens/immunology , Humans , Immunoglobulins, Intravenous , Immunosuppressive Agents/adverse effects , Kidney Transplantation/adverse effects , Male , Middle Aged , Patient Outcome Assessment , Rabbits , Survival Analysis , Tissue Donors , Transplantation, Homologous
17.
Urologe A ; 55(11): 1440-1445, 2016 Nov.
Article De | MEDLINE | ID: mdl-27680971

BACKGROUND: Various minimally invasive techniques are available for the surgical treatment of benign prostatic obstruction. Besides resection and enucleation, vaporization of the prostate is an attractive alternative. OBJECTIVES: The aim of the present article is to provide a comprehensive literature review on long-term results of GreenLight™ laser vaporisation and electrovaporisation of the prostate. MATERIALS AND METHODS: A literature search on long-term (≥5 years) results of GreenLight™ laser vaporization of the prostate and electrovaporisation of the prostate. RESULTS: Laser vaporization of the prostate with the GreenLight™ laser leads to an immediate and long-lasting improvement of voiding symptoms beyond 5 years. Currently, no long-term data of the 180 W laser model are available. With the former 80 W laser, an increased rate of reoperation due to recurrent obstruction has been described. As reoperation mainly occurs within the first 2 postoperative years, this suggests insufficient tissue ablation. Electrovaporisation of the prostate also leads to an improvement of voiding symptoms. However, only few studies on long-term results are available which report a relatively high rate of treatment failure. In addition, these studies have limitations in study design. CONCLUSIONS: Laser vaporisation of the prostate with the GreenLight™ laser seems to be an effective minimally invasive treatment alternative for BPO. However, long-term results of the current 180 W laser are still awaited. Based on limited data, electrovaporisation of the prostate currently cannot be recommended as an established treatment alternative.


Electrosurgery/methods , Laser Therapy/methods , Prostatic Hyperplasia/complications , Prostatic Hyperplasia/surgery , Urination Disorders/etiology , Urination Disorders/prevention & control , Humans , Longitudinal Studies , Male , Minimally Invasive Surgical Procedures/methods , Practice Guidelines as Topic , Prostatectomy/methods , Treatment Outcome
18.
Urologe A ; 55(10): 1375-1386, 2016 Oct.
Article De | MEDLINE | ID: mdl-27623798

Percutaneous nephrolithotomy (PCNL) is a well-established minimally invasive treatment option for removal of kidney stones. This technique has now replaced open stone surgery for virtually all indications. This article describes the indications, the surgical technique and the complication management of PCNL.


Kidney Calculi/surgery , Nephrostomy, Percutaneous/adverse effects , Nephrostomy, Percutaneous/methods , Postoperative Complications/etiology , Evidence-Based Medicine , Germany , Humans , Kidney Calculi/diagnosis , Minimally Invasive Surgical Procedures/adverse effects , Minimally Invasive Surgical Procedures/methods , Postoperative Complications/prevention & control , Treatment Outcome
20.
Aktuelle Urol ; 47(3): 210-3, 2016 05.
Article De | MEDLINE | ID: mdl-27096941

Urine culture (UC) confirms the diagnosis of urinary tract infection (UTI) and is still considered the diagnostic 'gold standard' for pathogen identification, quantification and resistance testing. However, up to 80% of samples will not yield bacterial growth. Different techniques are currently approved for resistance testing. However, all of them are culture based and have the disadvantage of being very slow. In the field of urology, the development of drug resistance of uropathogens complicates the optimal administration of antimicrobial agents not only in the treatment, but also in the prevention of UTI before endourological and open surgical procedures. In this context, rapid identification of microbiological agents, including timely antimicrobial resistance testing (ART) is desirable. This overview presents alternative techniques (flow cytometry, PCR-based techniques, MALDI-TOF MS and microcalorimetry) to urine culture and discusses their advantages and disadvantages.


Bacterial Infections/diagnosis , Urinary Tract Infections/diagnosis , Bacterial Infections/drug therapy , Bacteriological Techniques/methods , Bacteriuria/diagnosis , Bacteriuria/drug therapy , Calorimetry/methods , Drug Resistance, Microbial , Humans , Polymerase Chain Reaction/methods , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization/methods , Urinary Tract Infections/drug therapy
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