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Paweł Radkowski,1– 3 Michał Jacewicz,2 Iwona Podlińska,2 Maria Derkaczew2 1Department of Anaesthesiology and Intensive Care, Regional Specialist Hospital in Olsztyn, Olsztyn, Poland; 2Department of Anaesthesiology and Intensive Care, Faculty of Medicine, Collegium Medicum University of Warmia and Mazury in Olsztyn, Olsztyn, Poland; 3Department of Anaesthesiology and Intensive Care, Hospital zum Heiligen Geist in Fritzlar, Fritzlar, GermanyCorrespondence: Maria Derkaczew, Department of Anaesthesiology and Intensive Care, Faculty of Medicine, Collegium Medicum University of Warmia and Mazury in Olsztyn, Olsztyn, Poland, Email m.derkaczew@gmail.comIntroduction: Patients after chemotherapy and radiotherapy while being operated can suffer from different systemic problems, which may complicate the anesthetic management. Some interactions between muscle relaxants and chemotherapeutics can occur.Aim: This article aims to present the use of muscle relaxants in cancer patients who have undergone chemotherapy and radiotherapy.Material and Methods: Our work is based on the available literature and the authors’ experience.Conclusion: Based on our observations and a thorough examination of the medical literature, it is advisable to exercise significant caution when employing muscle relaxants in individuals undergoing chemotherapy and radiotherapy. All muscle relaxants can behave differently after chemotherapy and radiotherapy, and for this reason, practitioners should familiarize themselves with the pharmacodynamics and pharmacokinetics of their chosen muscle relaxant.Keywords: muscle relaxant, chemotherapy, radiotherapy

Paweł Radkowski,1– 3 Michał Jacewicz,2 Katarzyna Podhorodecka1 1Department of Anaesthesiology and Intensive Care, Regional Specialist Hospital in Olsztyn, Olsztyn, Poland; 2Department of Anaesthesiology and Intensive Care, Faculty of Medicine, Collegium Medicum University of Warmia and Mazury in Olsztyn, Olsztyn, Poland; 3Hospital zum Heiligen Geist, Fritzlar, GermanyCorrespondence: Paweł Radkowski, Department of Anaesthesiology and Intensive Care, Regional Specialist Hospital in Olsztyn, Żołnierska 18, Olsztyn, 10-561, Poland, Tel +48-882815714, Email k.podhorodecka1@gmail.comIntroduction: Anaesthetising a pregnant woman and during the postpartum period is challenging for most anaesthetists. There are many factors involved, including all the physiological changes that occur in the body of such a woman. Particular attention should be paid to muscle relaxants.Aim: The purpose of this article is to present the use of muscle relaxants in pregnancy and puerperium period.Material and Methods: This work is based on the available literature and the authors’ experience.Conclusion: In our experience and from a broad review of the medical literature, a great deal of caution should be exercised when using muscle relaxants during the anaesthesia of pregnant or postpartum patients. The pharmacodynamic and pharmacokinetic differences in the action of this group of drugs during this period should be known.Keywords: muscle relaxant, pregnancy, puerperium period, anaesthesia

Objective: To report non-infectious adverse events associated with transperineal prostate biopsy (TPBx) performed under local anaesthesia (LA) in an outpatient setting., Patients and Methods: This study reports secondary outcomes from the Norwegian arm of the prospective NORAPP study (ClinicalTrials.gov identifier NCT04146142) and included all patients referred for prostate biopsy from November 2019 to February 2021. Transperineal magnetic resonance imaging-transrectal ultrasonography fusion TPBx were taken using 40 mL 1% lidocaine with 4 mL of 8.4% sodium bicarbonate placed in the perineal skin, under the prostatic apex, in the m. levator ani bilaterally, and along the path of the needle. Follow-up using patient-reported questionnaires was done immediately after TPBx, and after 2 weeks and 2 months. Pain was reported using a visual analogue scale (VAS) during placement of the LA, and during and after TPBx. Haematuria and acute urinary retention (AUR) rates were recorded., Results: We included 402 patients, and the response rate was 99.8% (401/402). The median (interquartile range [IQR]) age was 69 (63-74) years, the prostate volume was 40 (27-58) mL, the prostate-specific antigen level was 7.0 (4.5-11) ng/mL, and the number of biopsy cores taken was 8 (6-10). The median (IQR) VAS pain score was 1 (1-2) during placement of LA, 1 (0-2) during TPBx, and 0 (0-0) after TPBx. Haematuria and AUR rates were 64% (95% confidence interval [CI] 60-69%) and 0.5% (95% CI 0.1-1.8%), respectively. No patients were hospitalised or required after the TPBx surgical intervention., Conclusion: Transperineal prostate biopsies can be performed under LA with limited discomfort to the patient and few post-TPBx adverse events., (© 2024 The Authors. BJU International published by John Wiley & Sons Ltd on behalf of BJU International.)

Objective: The European Association of Urology (EAU) recommends a bone scan for newly diagnosed unfavorable intermediate- and high-risk prostate cancer. We aimed to validate the screening criteria for bone metastases in patients with treatment-naïve prostate cancer., Methods: This single-center retrospective study included all patients with treatment-naïve unfavorable intermediate- or high-risk prostate cancer. All underwent MRI of the lumbar column (T2Dixon) and pelvis (3DT2w, DWI, and T2 Dixon). The presence and location of lymph node and bone metastases were registered according to risk groups and radiological (rad) T-stage. The risk of lymph node metastases was assessed by odds ratio (OR)., Results: We included 390 patients, of which 68% were high-risk and 32% were unfavorable intermediate-risk. In the high-risk group, the rate of regional- and non-regional lymph node metastases was 11% and 6%, respectively, and the rate of bone metastases was 10%. In the unfavorable intermediate-risk group, the rate of regional- and non-regional lymph node metastases was 4% and 0.8%, respectively, and the rate of bone metastases was 0.8%. Metastases occurred exclusively in the lumbar column in 0.5% of all patients, in the pelvis in 4%, and the pelvis and lumbar column in 3%. All patients with bone metastases had radT3-4, and patients with radT3-4 showed a four-fold increased risk of lymph node metastases (OR 4.48, 95% CI: 2.1-9.5)., Conclusion: Bone metastases were found in 10% with high-risk prostate cancer and 0.8% with unfavorable intermediate-risk. Therefore, we question the recommendation to screen the unfavorable intermediate-risk group for bone metastases., Key Points: • The rate of bone metastases was 10% in high-risk patients and 0.8% in the unfavorable intermediate-risk group. • The rate of lymph-node metastases was 17% in high-risk patients and 5% in the unfavorable intermediate-risk group. • No bone metastases were seen in radiologically localized disease., (© 2022. The Author(s).)

Frozen microspheres of hydrogen (pellets) are used as targets in the hadron physics experiment WASA (Forschungszentrum Jülich, Germany) [1] and will also be used in the future PANDA experiment at FAIR (GSI, Darmstadt, Germany) [2]. The interaction region is defined by the overlap of the pellet stream and the accelerator beam and has a size of a few millimeters. One would like to know the interaction point more precisely, to have better possibility to reconstruct particle tracks and events. One would also like to suppress background events that do not originate in a pellet, but e.g. may occur in residual gas in the beam pipe. A solution is provided by the presented pellet tracking system, for which a prototype [3] has been developed in Uppsala. The goal is to track individual pellets in order to know their position at the time of an interaction. The design of such a system, simulation techniques and results are presented.

Background: The benefit of antibiotic prophylaxis is uncertain when performing transperineal prostate biopsies. Judicious use of antibiotics is required as antimicrobial resistance increases worldwide. We aimed to assess whether antibiotic prophylaxis can be omitted when performing transperineal prostate biopsies under local anaesthesia as an outpatient procedure., Methods: In this randomised, open-label, non-inferiority trial, we aimed to enrol all patients with a suspicion of prostate cancer undergoing transperineal prostate biopsies at two hospitals in Norway and Germany. Patients with a high risk of infection or ongoing infection were excluded. Patients were randomised (1:1) to receive intramuscular (in Norway) or intravenous (in Germany) 1·5 g cefuroxime antibiotic prophylaxis or not. Follow-up assessments were done after 2 weeks and 2 months. The primary outcome was rate of sepsis or urinary tract infections requiring hospitalisation within 2 months. The secondary outcome was the rate of urinary tract infections not requiring hospitalisation. These outcomes were assessed in all eligible randomly allocated participants with a prespecified non-inferiority margin of 4%. Biopsies were performed using an MRI-transrectal ultrasound fusion transperineal technique under local anaesthesia. Patients with a positive MRI underwent 2-4 biopsies per target; in addition, 8-12 systematic biopsies were performed in biopsy naive and MRI-negative patients. This study is registered with ClinicalTrials.gov, NCT04146142., Findings: Between Nov 11, 2019, and Feb 23, 2021, 792 patients were referred for biopsy, of whom 555 (70%) were randomly allocated to treatment groups. 277 (50%) patients received antibiotic prophylaxis and 276 (50%) did not; two (<1%) patients were excluded after randomisation because of unknown allergy to study drug. Sepsis or urinary tract infections requiring hospitalisation occurred in no patients given antibiotic prophylaxis (0%, 95% CI 0 to 1·37) or not given antibiotic prophylaxis (0%, 0 to 1·37; difference 0% [95% CI -1·37 to 1·37]). Urinary tract infections not requiring hospitalisation occurred in one patient given antibiotic prophylaxis (0·36%, 95% CI 0·01 to 2·00) and three patients not given antibiotic prophylaxis (1·09%, 0·37 to 3·15; difference 0·73% [95% CI -1·08 to 2·81]). The number needed to treat with antibiotic prophylaxis to avoid one infection was 137., Interpretation: The non-inferiority margin of 4% was not exceeded, suggesting rates of infections were not higher in patients not receiving antibiotic prophylaxis before transperineal prostate biopsy than in those receiving it. Therefore, antibiotic prophylaxis might be omitted in this population., Funding: Oslo University Hospital, Oslo, Norway and Vivantes Klinikum Am Urban, Berlin, Germany., Competing Interests: Declaration of interests We declare no competing interests., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Identification of a spinning projectile controlled with gasodynamic engines is shown in this paper. A missile model with a measurement inertial unit was developed from Newton's law of motion and its aerodynamic coefficients were identified. This was achieved by applying the maximum likelihood principle in the wavelet domain. To assess the results, this was also performed in the time domain. The outcomes were obtained for two cases: when noise was not present and when it was included in the data. In all cases, the identification was performed in the passive mode, i.e., no special system identification experiments were designed. In the noise-free case, aerodynamic coefficients were estimated with high accuracy. When noise was included in the data, the wavelet-based estimates had a drop in their accuracy, but were still very accurate, whereas for the time domain approach the estimates were considered inaccurate.

The article presents the analysis of the impact point dispersion reduction using lateral correction thrusters. Two types of control algorithms are used and four sources of uncertainties are taken into account: aerodynamic parameters, thrust curve, initial conditions and IMU errors. The Monte Carlo approach was used for simulations and Circular Error Probable was used as a measure of dispersion. Generic rocket mathematical and simulation model was created in MATLAB/Simulink 2020b environment. Results show that the use of control algorithms greatly reduces the impact point dispersion.

Background/aim: The aim of this study was to evaluate the cancer detection rate (CDR) using magnetic resonance imaging-transrectal ultrasound (MRI-TRUS) fusion-guided transperineal targeted biopsy (TB)., Patients and Methods: We included 401 consecutive patients, of which 161 were biopsy-naïve. All underwent prebiopsy bi-parametric MRI; patients with positive MRI [prostate imaging reporting and data system (PI-RADS≥3)] underwent TB. Biopsy-naïve patients with positive MRI underwent TB and systematic biopsies (SBs). MRI-negative patients underwent SBs. Clinically significant prostate cancer (csPCa) was defined as ISUP ≥2. The added value of SB was defined as an upgrade from a negative biopsy or ISUP of 1 in TB to csPCa in SB., Results: The median (interquartile range) age was 69 (range=63-74) years, and PSA was 6.9 (range=4.5-11) ng/ml. The overall CDR was 65%, with csPCa occurring in 48%. In cases of PI-RADS 5, CDR was 91%, and csPCa was 77%. The added value of SB was 2%., Conclusion: Transperineal TB biopsies using MRI-TRUS fusion yield a high CDR., (Copyright © 2021 International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.)

Introduction: Transperineal Prostate biopsies (TPBx) are usually performed under general anesthesia without image fusion. This study aimed to evaluate prostate cancer (Pca) detection rates (CDR), pain, and adverse events using a novel, free-hand TPBx technique, based on elastic fusion of magnetic resonance imaging (MRI) and transrectal ultrasound (TRUS) under local anesthesia., Materials and Methods: This multicenter retrospective study included all consecutive patients scheduled for a TPBx. All had clinical suspicion of Pca, active surveillance scheduled for a re-biopsy, or suspicion of local recurrence after previous treatment. Bi-parametric or multiparametric MRI was performed in all patients and classified as positive in the case of Prostate Imaging-Reporting and Data System (PIRADS) suspicion ≥3. At least 1 targeted TPBx was realized from each PIRADS ≥3 index lesion. Six to 12 systematic random TPBx were done in patients with negative MRI. All biopsies were performed under local anesthesia in an outpatient clinic with MRI-TRUS fusion and the 3D navigation system Trinity Perine (Koelis, France). Any- and clinically significant Pca (csPca) (ISUP gr. ≥2) was recorded. Biopsy-related pain and adverse events were reported according to a visual analogue score of 0-10., Results: In total, 377 patients were included for analyses. The mean age was 67 years (95% Confidence Interval: 66-68) and the median prostate-specific antigen was 7.2 ng/ml (interquartile range [IQR] 4.8-11.0). MRI was negative in 6% and positive in 94%. The median MRI prostate volume was 43 ml (IQR 31-60) and the median MRI index tumor volume was 0.9 ml (IQR 0.5-2.1). The median number of TPBx was 4 (IQR 3-4). The overall detection of any- and csPca was 64% and 52%, respectively. The overall CDR according to PIRADS 3, 4, and 5 was 30%, 70%, and 94%, respectively. In patients with negative MRI, any- and csPca was detected in 23% and 9%, respectively. The median visual analogue score score was 2 (IQR 1-3, range 0-7). Two patients (0.5%) developed postbiopsy infection, of which one developed urosepsis. Treatment requiring haematuria or urinary retention did not occur., Conclusion: Free-hand MRI/TRUS fusion-guided and systematic random TPBx in LA is a feasible, safe, and well-tolerated technique for diagnosing Pca., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Background: Despite the relatively low infection rate following transperineal prostate biopsy (TPB), it remains unresolved whether periprocedural antibiotic prophylaxis (PAP) can be omitted. Our aim was to compare infectious complications (genitourinary infections/GUI, fever, sepsis, readmission rate, 30-day-mortality) following TPB, considering all studies of varying levels of evidence that enable a direct comparison between patients with and without PAP., Methods: We performed a comprehensive search in PubMed/Medline, Embase, Web of Science, and Cochrane databases, as well as grey literature sources, to identify reports published until January 2024. All studies comparing the incidence of infectious endpoints following TPB with vs. without PAP were included in the analyses. The GRADE approach was employed to assess the certainty of evidence for each comparison., Results: Twenty-three studies met the inclusion criteria involving 6520 and 5804 patients who underwent TPB with vs. without PAP, respectively. Two of the 23 studies were randomized-controlled trials, not all studies investigated all endpoints. Pooled incidences between patients with vs. without PAP for the endpoints GUI (0.50% vs. 0.37%), fever (0.44% vs. 0.26%), sepsis (0.16% vs. 0.13%), and readmission rate (0.35% vs. 0.29%) showed no significant differences (all p > 0.250). The corresponding odds ratios (including 95% confidence interval) also revealed no statistically significant differences: 1.37 (0.74-2.54) [GUI], 0.87 (0.28-2.66) [fever], 1.30 (0.46-3.67) [sepsis], and 1.45 (0.70-3.03) [readmission rate]. No study reported events regarding 30-day-mortality. In subgroup analyses and sensitivity analyses, TPB without PAP showed no significantly higher complication rates regarding all analyzed endpoints., Conclusions: Infectious complications after TPB occur very rarely and cannot be further reduced by PAP. Considering the results of this systematic review and adhering to the principles of effective antibiotic stewardship, omitting PAP in the context of TPB is advisable., Competing Interests: Competing interests: Ingmar Wolff certifies that all conflicts of interest, including specific financial interests and relationships and affiliations relevant to the subject matter or materials discussed in the manuscript (eg, employment/affiliation, grants or funding, consultancies, honoraria, stock ownership or options, expert testimony, royalties, or patents filed, received, or pending), are the following: Florian Wagenlehner und Adrian Pilatz contributed to the current Guidelines of the European Association of Urology on Urological Infections. Katharina Hauner, Marianne Abele-Horn, and Matthias May contributed to the current German S3-Guidelines on Perioperative/Periprocedural Antibiotic Prophylaxis., (© 2024. The Author(s).)

INTRODUCTION    The prevalence of polycystic ovary syndrome (PCOS) among women with type 1 diabetes (T1DM) is higher than in the general population. Both diseases are associated with higher risk of premature atherosclerosis. OBJECTIVES    The aim of our study was to evaluate whether the cardiovascular risks conferred by T1DM and PCOS are additive. PATIENTS AND METHODS   The study group included 78 women divided into 4 groups: 19 women with PCOS and T1DM (T1DM+PCOS), 16 women with T1DM only (T1DM/no‑PCOS), 27 women with PCOS only(PCOS), and 16 healthy women (control group). We evaluated the serum concentrations of cardiovascular disease biomarkers: soluble intercellular adhesion molecule 1 (sICAM‑1) and soluble endothelial‑leukocyte adhesion molecule 1 (sE‑selectin). We also assessed brachial artery flow‑mediated dilation (FMD) and estimated the intima-media thickness of the common carotid artery (CIMT) by ultrasonography. RESULTS    The serum concentrations of sICAM‑1and sE‑selectin were higher in the T1DM+PCOS group compared with women with PCOS only (P = 0.041 and P = 0.002, respectively) and were comparable to those in the T1DM/no‑PCOS group. FMD and CIMT did not differ between the groups. In women with T1DM, sICAM‑1 positively correlated with body mass index (r = 0.34, P = 0.047), CIMT with daily insulin dose (r = 0.37, P = 0.039), and FMD negatively correlated with diabetes duration (r = -0.42, P = 0.02). In a multivariable logistic regression model, the presence of T1DM, with adjustment for sICAM‑1, was the only predictor of sE‑selectin concentrations in the whole study group (odds ratio, 8.03; 95% confidence interval, 2.56-13.49; P = 0.005). CONCLUSIONS    The presence of PCOS does not increase the risk of subclinical vascular disease in young lean women with T1DM.

Shiga toxin is a potent protein toxin produced by Shigella dysenteriae type I strains. In this report we present a procedure for the separation of functionally intact toxin A and B chains and for their reconstitution to form biologically active molecules. In agreement with the findings of others, the isolated A chain was shown to be a potent in vitro inhibitor of eukaryotic protein synthesis. The isolated B chain bound to HeLa cells and competitively inhibited the binding and cytotoxic activity of holotoxin. These findings show that the functional rote of the B chain is to recognize cell surface functional receptors. By labelling the B subunit alone, prior to renaturation of holotoxin, the polypeptide chains were shown to associate noncovalently with a stoichiometry of one A chain and five B chains. [ABSTRACT FROM AUTHOR]

Introduction: Data underline the role of betatrophin in glucose homeostasis. Polycystic ovary syndrome (PCOS) is characterized by insulin resistance (IR). The aim of our study was to investigate the relationship of serum betatrophin concentrations with indirect indices of IR and insulin secretion in women with PCOS, compared to the control group., Methods: The study group comprised 43 women with PCOS and 16 controls. IR was assessed by HOMA-IR and Matsuda index. Insulin secretion was evaluated with HOMA-B. An oral glucose tolerance test (OGTT) with estimation of serum betatrophin concentrations was performed., Results: Glucose load resulted in an increase in serum betatrophin concentrations in the control group ( p = 0.02). Serum betatrophin concentrations at 120 min of OGTT were lower in women with PCOS than in the control group ( p = 0.02). We observed positive correlations between baseline serum betatrophin concentrations and HOMA-IR ( r = 0.39, p = 0.008), negative correlations with Matsuda index ( r = -0.31, p = 0.004), and a positive relationship with HOMA-B ( r = 0.38, p = 0.01) in women with PCOS. Multiple regression analysis revealed that HOMA-B ( β = 0.47, p = 0.001) was an independent factor connected to serum betatrophin levels in PCOS., Conclusions: Serum concentrations of betatrophin are connected with insulin resistance and beta cell function and did not change after glucose load in women with PCOS.

The cross-sections of the pd $ \rightarrow$3He $ \eta$ , pd $ \rightarrow$3He $ \pi^{0}_{}$ $ \pi^{0}_{}$ $ \pi^{0}_{}$ and pd $ \rightarrow$3He $ \pi^{+}_{}$ $ \pi^{-}_{}$ $ \pi^{0}_{}$ reactions have been measured at the beam kinetic energies Tp= 1360 MeV and Tp= 1450 MeV using the CELSIUS/WASA detector setup. At both energies, the differential cross-section $\tfrac{{d\sigma }} {{d\Omega }}$ of the $ \eta$ meson in the pd $ \rightarrow$3He $ \eta$ reaction shows a strong forward-backward asymmetry in the CMS. The ratio between the pd $ \rightarrow$3He $ \pi^{+}_{}$ $ \pi^{-}_{}$ $ \pi^{0}_{}$ and pd $ \rightarrow$3He $ \pi^{0}_{}$ $ \pi^{0}_{}$ $ \pi^{0}_{}$ cross-sections has been analysed in terms of isospin amplitudes. The reconstructed invariant-mass distributions of the $ \pi$ $ \pi$ , 3He $\displaystyle \pi$ and 3He2 $ \pi$ systems provide hints on the role of nucleon resonances in the 3 $ \pi$ production process. [ABSTRACT FROM AUTHOR]

The production of η mesons at an excess energy of 72 MeV has been studied in the reaction pp → pp(η)γγ. It is shown that a simple model with Pp final states included reproduces observed differential distributions better than the same model restricted to Ss, Sd and Ds final states. The strong influence of the Pp states could be taken as an indication of ρ dominance within an one boson exchange model for the excitation of N*(1535). [ABSTRACT FROM AUTHOR]

The two-pion production in pp-collisions has been investigated in exclusive measurements from threshold up to Tp = 1.36 GeV. Total and differential cross sections have been obtained for the channels pnπ+π0, ppπ+π-, ppπ0π0 and also nnπ+π+. For intermediate incident energies Tp > 1 GeV, i.e. in the region, which is beyond the Roper excitation but at the onset of ΔΔ excitation the total ppπ0π0 cross section falls behind theoretical predictions by as much as an order of magnitude near 1.2 GeV, whereas the nnπ+π+ cross section is a factor of five larger than predicted. A model-unconstrained isospin decompostion of the cross section points to a significant contribution of an isospin 3/2 resonance other than the Δ(1232). As a possible candidate the Δ(1600) is discussed. [ABSTRACT FROM AUTHOR]

Abstract: The cross section for direct neutral and charged three pion production in pp interactions was measured at excess energies in the range 160–216 MeV. That comprises the first measurement of the reaction and the direct comparison with the process. The experiment was performed above the η meson production threshold and the cross section could be directly normalized to the cross section of the reaction, with the η decaying into 3 pions. Since the same final states are selected, the measurement has a low systematical error. The measured cross section ratio is compared to predictions of dominance of different isobars in the intermediate state. [Copyright &y& Elsevier]

The reaction pn → dπ0π0 constitutes the most fundamental system for the study of the ABC effect - a puzzling threshold enhancement in the ππ invariant mass spectrum of the ππ system in double-pionic fusion to nuclear bound states. The first exclusive measurements of this reaction have now been carried out at CELSIUS-WASA. They exhibit a striking low-mass enhancement in the ππ invariant mass spectrum, prove it to be a σ-channel phenomenon and falsify conventional theoretical models, which predict an associated high-mass enhancement not present in the new exclusive data. In the kinematically complete data sample we observe a ΔΔ excitation, where the interaction between the two Δ obviously plays a crucial role for the generation of the ππ low-mass enhancement. [ABSTRACT FROM AUTHOR]

At CELSIUS-WASA the two-pion production in proton-proton collisisons has been measured exclusively from threshold up to the energy regime, where both of the collision partners are expected to be excited to the Δ state. The measurements constitute the first kinematically complete data samples of solid statistics in this energy range. Most of the data have been obtained for the π+π- and π0π0channels. Whereas at near-threshold energies the differential distributions can be succesfully explained by chiral dynamics and Roper excitation, respectively, the data for the π+π- channel in the ΔΔ region can be described only, if the special configuration (ΔΔ)0+ is assumed. The data for the π0π0 channel moreover exhibit a low-mass enhancement in the π0π0 invariant mass spectrum, which is reminiscent of the ABC-effect found in double-pionic fusion to light nuclei. [ABSTRACT FROM AUTHOR]

The ABC effect - a puzzling threshold enhancement in the ππ invariant mass spectrum of double-pionic fusion to nuclear bound states - has been investigated since 40 years by inclusive measurements without providing a conclusive interpretation. First exclusive measurements to this topic have now been carried out at CELSIUS-WASA. They confirm a huge ππ threshold enhancement, prove it to be of scalar-isoscalar nature, i.e., a σ-channel phenomenon and reveal the theoretically predicted high-mass enhancement in inclusive spectra to be of πππ rather than of ππ nature - falsifying thus corresponding model predictions for the ABC effect. From the kinematically complete data samples we infer that the interaction between the two Δ particles created in this process is of crucial importance. [ABSTRACT FROM AUTHOR]

Electron emission from micro-protrusions on the surface of metal electrodes is crucial for vacuum breakdown. The emission characteristics of cathode micro-protrusions and the impact of the space charge effect are investigated in this study, with a comparison to the Murphy–Good (MG) theory analysis. Precise calculations of the emission current density and the Nottingham effect are achieved. A thermal-field emission model for copper micro-protrusion is established to analyze emission characteristics and clarify the mismatches between the results of simulations and MG theory. The results indicate that, for copper micro-protrusions, before breakdown, the emission current is primarily field emission, with thermal emission constituting only 7% of the total. The Nottingham effect results in consistent heating during this phase. The field enhancement factor obtained through the MG theory (γ MG) is slightly smaller than that derived from the geometric model (γ geom). This is because γ geom reflects the characteristics of the apex of the protrusion, while γ MG reflects the characteristics of the entire electron emission region. The space charge effect bends the MG plot curve and decreases its slope, making it impossible to analyze the emission current using MG theory at this point, which is consistent with the theoretical derivations recorded in the current literature. [ABSTRACT FROM AUTHOR]