First Probe of Sub-GeV Dark Matter beyond the Cosmological Expectation with the COHERENT CsI Detector at the SNS.

The COHERENT Collaboration searched for scalar dark matter particles produced at the Spallation Neutron Source with masses between 1 and 220 MeV/c^{2} using a CsI[Na] scintillation detector sensitive to nuclear recoils above 9 keV_{nr}. No evidence for dark matter is found and we thus place limits on allowed parameter space. With this low-threshold detector, we are sensitive to coherent elastic scattering between dark matter and nuclei. The cross section for this process is orders of magnitude higher than for other processes historically used for accelerator-based direct-detection searches so that our small, 14.6 kg detector significantly improves on past constraints. At peak sensitivity, we reject the flux consistent with the cosmologically observed dark-matter concentration for all coupling constants α_{D}<0.64, assuming a scalar dark-matter particle. We also calculate the sensitivity of future COHERENT detectors to dark-matter signals which will ambitiously test multiple dark-matter spin scenarios.

Measurement of Electron-Neutrino Charged-Current Cross Sections on

Using an 185-kg NaI[Tl] array, COHERENT has measured the inclusive electron-neutrino charged-current cross section on ^{127}I with pion decay-at-rest neutrinos produced by the Spallation Neutron Source at Oak Ridge National Laboratory. Iodine is one the heaviest targets for which low-energy (≤50 MeV) inelastic neutrino-nucleus processes have been measured, and this is the first measurement of its inclusive cross section. After a five-year detector exposure, COHERENT reports a flux-averaged cross section for electron neutrinos of 9.2_{-1.8}^{+2.1}×10^{-40} cm^{2}. This corresponds to a value that is ∼41% lower than predicted using the MARLEY event generator with a measured Gamow-Teller strength distribution. In addition, the observed visible spectrum from charged-current scattering on ^{127}I has been measured between 10 and 55 MeV, and the exclusive zero-neutron and one-or-more-neutron emission cross sections are measured to be 5.2_{-3.1}^{+3.4}×10^{-40} and 2.2_{-0.5}^{+0.4}×10^{-40} cm^{2}, respectively.

Measurement of the Coherent Elastic Neutrino-Nucleus Scattering Cross Section on CsI by COHERENT.

We measured the cross section of coherent elastic neutrino-nucleus scattering (CEvNS) using a CsI[Na] scintillating crystal in a high flux of neutrinos produced at the Spallation Neutron Source at Oak Ridge National Laboratory. New data collected before detector decommissioning have more than doubled the dataset since the first observation of CEvNS, achieved with this detector. Systematic uncertainties have also been reduced with an updated quenching model, allowing for improved precision. With these analysis improvements, the COHERENT Collaboration determined the cross section to be (165_{-25}^{+30})×10^{-40} cm^{2}, consistent with the standard model, giving the most precise measurement of CEvNS yet. The timing structure of the neutrino beam has been exploited to compare the CEvNS cross section from scattering of different neutrino flavors. This result places leading constraints on neutrino nonstandard interactions while testing lepton flavor universality and measures the weak mixing angle as sin^{2}θ_{W}=0.220_{-0.026}^{+0.028} at Q^{2}≈(50 MeV)^{2}.

First Measurement of Coherent Elastic Neutrino-Nucleus Scattering on Argon.

We report the first measurement of coherent elastic neutrino-nucleus scattering (CEvNS) on argon using a liquid argon detector at the Oak Ridge National Laboratory Spallation Neutron Source. Two independent analyses prefer CEvNS over the background-only null hypothesis with greater than 3σ significance. The measured cross section, averaged over the incident neutrino flux, is (2.2±0.7)×10^{-39} cm^{2}-consistent with the standard model prediction. The neutron-number dependence of this result, together with that from our previous measurement on CsI, confirms the existence of the CEvNS process and provides improved constraints on nonstandard neutrino interactions.

Recent evidence for anatomic endoscopic enucleation of the prostate (AEEP) in patients with benign prostatic obstruction on antiplatelet or anticoagulant therapy.

INTRODUCTION: Due to demographic changes in today's society, the number of patients with lower urinary tract symptoms (LUTS) due to benign prostatic hyperplasia (BPH) is increasing. Similarly, the proportion of patients with cardiovascular risk factors undergoing antiplatelet (AP) or anticoagulation (AC) therapy is growing as well. METHODS: This review discusses the current literature on various techniques used for anatomic endoscopic enucleation of the prostate (AEEP) in patients on AC/AP therapy. RESULTS: The large number of energy sources used for AEEP makes it difficult to compare them. Overall, fewer bleeding-associated complications arise in patients under AP compared to AC or bridging therapy with low molecular weight heparin. However, perioperatively both AP and AC therapy lead to a higher risk of bleeding complications compared to patients not taking anticoagulants. CONCLUSIONS: The literature shows that AEEP is possible and efficacious in patients under AC/AP therapy, with only slight differences compared to patients not taking AC/AP drugs, on a short and long-term basis. Nevertheless, the sparse data, the retrospective nature of many studies and the inclusion of prostate sizes between 50 and 110 ml only, make it difficult to come to strong conclusions.

Rectal perforation after aquablation of the prostate: lessons learned the hard way.

INTRODUCTION: Transurethral resection of the prostate and open prostatectomy have been the standard of care for the surgical treatment of benign prostatic obstruction (BPO) over decades. New emerging techniques for the surgical management of BPO have been currently introduced, but might be associated with new, unusual complications. METHODS: We herewith report on two patients with a rectal perforation after aquablation treatment of BPO. RESULTS: In the first case, the diagnosis was made 2 days after the aquablation procedure due to unspecific postoperative symptoms. A complex combined open/endoscopic repair of the defect was carried out thereafter. As a consequence, a rectoscopy was routinely performed since then following each aquablation procedure. In the second case, intraoperative rectoscopy after uneventful aquablation revealed the rectal perforation. The perforation was clipped immediately with an over the scope-clip by colonoscopy. CONCLUSIONS: These two cases of a rectal perforation after aquablation of the prostate demonstrate an unusual complication and its complex management. Diagnostic delay complicates its treatment. Therefore, immediate rectoscopy should be performed routinely after the aquablation procedure.

Reasons to go for thulium-based anatomical endoscopic enucleation of the prostate.

PURPOSE: To summarize the current evidence and the reasons to go for thulium-based anatomical endoscopic enucleation of the prostate (AEEP). METHODS: This review discusses the available literature on thulium-based AEEP. RESULTS: Thulium lasers operate at a wavelength between 1940 and 2013 nm. This wavelength, which has a low penetration depth in water, allows to perform smooth cuts in the prostatic tissue and allows urologists to perform various procedures: resection, vaporization, enucleation, or vapoenucleation of the prostate. Depending on the type of thulium laser, it can be used either in a continuous, or pulsed mode. CONCLUSION: In recent years, an increasing amount of evidence has described the thulium laser as a minimally invasive and size-independent treatment option for benign prostatic enlargement with excellent long-term results.

[Vaccination against Covid19: between individual responsability and moral sense]. / La vaccination contre la COVID-19 : entre responsabilité individuelle et sens moral.

Vaccination against COVID-19, which began at the end of last year, promises to be one of the most passionate societal debates of the beginning of 2021. Should we force the population to vaccinate in the name of the civic duty to protect the most vulnerable among us? Should it still be left to the choice of the free and enlightened citizen, which guarantees the consequences it therefore evokes, in the name of what the Republic has most precious to offer: the freedom to choose and the equality of all in front of it? But where should this democratic freedom of action and decisions stop, as long as they must undermine the safety of the life course of some of us? Faced with this pandemic, who should decide who should live with the individuality defended by some or take the risk of peer contamination by refusing vaccination? This would make us lose then and together what we owe to ourselves, but above all what we owe to others: the sense of a certain consideration of human vulnerability, and respect for the precious price of life. The philosophy of freedom and the ethics of responsibility will help us to shed a certain humanist light on our individual and collective decisions that today herald the common plan for a shared future that concerns us all.

Safety and efficacy using a low-powered holmium laser for enucleation of the prostate (HoLEP): 12-month results from a prospective low-power HoLEP series.

PURPOSE: To analyze the 12-month outcomes of low-powered holmium laser enucleation of the prostate (LP-HoLEP) for patients with symptomatic benign prostatic obstruction (BPO). METHODS: A total of 54 patients with symptomatic BPO were treated with LP-HoLEP. All patients were treated by two experienced LP-HoLEP surgeons. A 50-W Ho:YAG laser was used at 39.6-W (2.2 J, 18 Hz). All patients were assessed preoperatively by International Prostate Symptom Score (IPSS), quality of life (QoL), maximum flow rate (Qmax), post-void residual urine (PVR), PSA, and whole prostate volume measurement by transrectal ultrasound. The patients were reassessed at 1-, 6-, and 12-month follow-up. The complications were classified according to the modified Clavien classification system. Patient data were expressed as median (interquartile range) or numbers (%). RESULTS: The median age was 72.5 (67-77.25) years and the median preoperative prostate volume 74.5 (45-110) ml. 12 (22.2%) patients were treated with ongoing anticoagulant treatment. The median operative time was 65 (41-81) min and the enucleation efficiency 1.11 (0.82-1.79) g/min, respectively. Clavien 1 (11.1%), Clavien 2 (3.7%), Clavien 3a (3.7%), and Clavien 3b (5.5%) complications occurred. At 6-month follow-up, median prostate volume (74.5 vs. 15.5 ml) and PSA (4.03 vs. 0.54 µg/l) had improved significantly compared to baseline (p ≤ 0.009). At 12-month follow-up, Qmax (12 vs. 29.3 ml/s), PVR (155 vs. 11.15 ml), IPSS (22 vs. 6) and QoL (5 vs. 1) had improved significantly (p < 0.001). CONCLUSIONS: LP-HoLEP is technically feasible, safe and effective for the treatment of symptomatic BPO. For experienced surgeons, power is less relevant than technique.

Thulium vapoenucleation of the prostate versus holmium laser enucleation of the prostate for the treatment of large volume prostates: preliminary 6-month safety and efficacy results of a prospective randomized trial.

PURPOSE: We compared the perioperative and postoperative characteristics of thulium vapoenucleation and holmium laser enucleation of the prostate for the treatment of large volume benign prostatic hyperplasia. MATERIALS AND METHODS: A total of 94 patients with benign prostatic hyperplasia and a median prostate size of 80 (IQR 46.75-100) cc were either randomized to thulium vapoenucleation or holmium laser enucleation of the prostate. Patients were assessed preoperatively, 1 and 6 months postoperatively. RESULTS: The median operative time was 60 (IQR 41-79) min without significant differences between the groups. There were no significant differences between the groups regarding catheter time [2 (IQR 2-2) days] and postoperative stay [2 (IQR 2-3) days]. Clavien 1 (13.8%), 2 (3.2%), 3a (2.1%), and Clavien 3b (4.3%) complications occurred without significant differences between the groups. At 6-month follow-up, median maximum flow rate (10.7 vs. 25.9 ml/s), post-void residual urine (100 vs. 6.5 ml), I-PSS (20 vs. 5), quality of life (4 vs. 1), PSA (4.14 vs. 0.71 µg/l), and prostate volume (80 vs. 16 ml) had improved significantly (p < 0.001) compared to baseline without significant differences between the groups. Median PSA decrease was 79.7% (58.8-90.6%) and prostate volume reduction was 74.5% (68.57-87.63%) without differences between the groups. The reoperation rate was zero at 6-month follow-up. CONCLUSIONS: Thulium vapoenucleation and holmium laser enucleation of the prostate are safe and effective procedures for the treatment of large volume benign prostatic hyperplasia. Both procedures give satisfactory micturition improvement with low morbidity and sufficient prostate volume reduction at 6-month follow-up.

Five-year outcomes of thulium vapoenucleation of the prostate for symptomatic benign prostatic obstruction.

INTRODUCTION AND OBJECTIVES: To assess the 5-year outcomes of thulium vapoenucleation of the prostate (ThuVEP) in patients with benign prostatic obstruction (BPO) retrospectively. METHODS: Five-hundred patients were treated with ThuVEP between January 2007 and January 2010 at our institution. Patients were reassessed 1 and 5-years after ThuVEP with International Prostate Symptom Score (IPSS), Quality of Life (QoL), urinary peak flow (Qmax), postvoid residual volume (PVR), PSA and prostate volume. Patient data were expressed as median (interquartile range). RESULTS: One-hundred and thirty-one patients completed the 5-year follow-up. According to preoperative prostate volume, patients were divided into two groups: group A (<60 ml, n = 80) and B (≥60 ml, n = 51). IPSS, QoL, Qmax, and PVR improved significantly at discharge and continued to do so during 5-year follow-up (p ≤ 0.001). At 1-year follow-up, prostate volume had decreased significantly (50 vs. 13 mL, p < 0.001) corresponding to a prostate volume reduction of 80.8%. PSA was significantly reduced at 5-year (0.72 µg/l) follow-up compared to preoperative PSA (3.39 µg/l, p ≤ 0.001). PSA-reduction (total 77.1%) at 5-year follow-up was significantly different between group A (70.2%) and B (83.5%) (p ≤ 0.006). IPSS was significantly lower in group B than in A (2.5 vs. 6, p < 0.001) at 5-year follow-up. Bladder neck contractures (n = 4) and urethral strictures (n = 4) occurred in 3.1% of the patients each. Three patients (2.3%) were re-treated for regrowth of prostatic tissue. CONCLUSIONS: ThuVEP is a durable procedure with regard to micturition improvement and PSA-reduction. The reintervention rate after ThuVEP was low during long-term follow-up.

A prospective, randomized trial comparing thulium vapoenucleation with holmium laser enucleation of the prostate for the treatment of symptomatic benign prostatic obstruction: perioperative safety and efficacy.

INTRODUCTION AND OBJECTIVES: To compare the perioperative outcomes of thulium vapoenucleation of the prostate (ThuVEP) with holmium laser enucleation of the prostate (HoLEP) for patients with symptomatic benign prostatic obstruction (BPO). METHODS: Forty-eight and 46 patients were prospectively randomized to ThuVEP and HoLEP. All patients were assessed preoperatively and 4-week postoperatively. The complications were noted and classified according to the modified Clavien classification system. Patient data were expressed as median (interquartile range) or numbers (%). RESULTS: Median age at surgery was 73 (67-76) years and median prostate volume was 80 (46.75-100) cc and not different between the groups (p = 0.207). The median operative time was 60 (41-79) minutes without significant differences between both groups (p = 0.275). There were no significant differences between the groups regarding catheterization time [2 (2-2) days, p = 0.966] and postoperative stay [2 (2-3) days, p = 0.80]). Clavien 1 (13.8%), Clavien 2 (3.2%), Clavien 3a (2.1%), and Clavien 3b (4.3%) complications occurred without significant differences between the groups. However, the occurrence of acute postoperative urinary retention was higher after HoLEP compared to ThuVEP (15.2 vs. 2.1%, p ≤ 0.022). At 1-month follow-up, peak urinary flow rates (10.7 vs. 22 ml/s), post-void residual volumes (100 vs. 20 ml), International Prostate Symptom Score (20 vs. 10) and Quality of Life (4 vs. 3) had improved significantly (p ≤ 0.005) without significant differences between the groups. CONCLUSIONS: ThuVEP and HoLEP are safe and effective procedures for the treatment of symptomatic BPO. Both procedures give equivalent and satisfactory immediate micturition improvement with low perioperative morbidity.

Effects of ketamine on brain function during smooth pursuit eye movements.

The uncompetitive NMDA receptor antagonist ketamine has been proposed to model symptoms of psychosis. Smooth pursuit eye movements (SPEM) are an established biomarker of schizophrenia. SPEM performance has been shown to be impaired in the schizophrenia spectrum and during ketamine administration in healthy volunteers. However, the neural mechanisms mediating SPEM impairments during ketamine administration are unknown. In a counter-balanced, placebo-controlled, double-blind, within-subjects design, 27 healthy participants received intravenous racemic ketamine (100 ng/mL target plasma concentration) on one of two assessment days and placebo (intravenous saline) on the other. Participants performed a block-design SPEM task during functional magnetic resonance imaging (fMRI) at 3 Tesla field strength. Self-ratings of psychosis-like experiences were obtained using the Psychotomimetic States Inventory (PSI). Ketamine administration induced psychosis-like symptoms, during ketamine infusion, participants showed increased ratings on the PSI dimensions cognitive disorganization, delusional thinking, perceptual distortion and mania. Ketamine led to robust deficits in SPEM performance, which were accompanied by reduced blood oxygen level dependent (BOLD) signal in the SPEM network including primary visual cortex, area V5 and the right frontal eye field (FEF), compared to placebo. A measure of connectivity with V5 and FEF as seed regions, however, was not significantly affected by ketamine. These results are similar to the deviations found in schizophrenia patients. Our findings support the role of glutamate dysfunction in impaired smooth pursuit performance and the use of ketamine as a pharmacological model of psychosis, especially when combined with oculomotor biomarkers. Hum Brain Mapp 37:4047-4060, 2016. © 2016 Wiley Periodicals, Inc.

Bovine non-competent oocytes (BCB-) negatively impact the capacity of competent (BCB+) oocytes to undergo in vitro maturation, fertilisation and embryonic development.

Competent oocyte selection remains a bottleneck in the in vitro production (IVP) of mammalian embryos. Among the vital assays described for selecting competent oocytes for IVP, the brilliant cresyl blue (BCB) test has shown consistent results. The aim of the first experiment was to observe if oocytes directly submitted to IVM show similar cleavage and blastocyst rates as those obtained with oocytes maintained under the same in vitro conditions as the oocytes that undergo the BCB test. Bovine cumulus-oocyte complexes (COCs) were recovered from slaughterhouse-derived ovaries and, after morphological evaluation, were randomised grouped into three groups: (1) directly submitted to IVM; (2) oocytes submitted to the BCB test without the addition of BCB stain (BCB control group); and (3) submitted to the BCB test. The results showed that oocytes directly submitted to IVM reached similar cleavage (48/80 - 60%) and embryonic development rates to the blastocyst stage (10/48 - 21%) as the results obtained with the BCB control group oocytes (45/77 - 58% and 08/45 - 18%, respectively). The aim of the second experiment was to determine the cleavage and blastocyst rates obtained from BCB+ oocytes undergoing IVM in the presence of BCB- oocytes at a ratio of 10:1. COCs were recovered from slaughterhouse-derived ovaries and, after morphological evaluation, were randomised into two groups that were submitted to IVM either directly (1: control group) or submitted to the BCB test prior to IVM. After the BCB test, the COCs were classified as either BCB+ (blue cytoplasm) or BCB- (colourless cytoplasm) and then divided into four experimental groups: (2) BCB+; (3) BCB-; and (4) BCB+ matured in same IVM medium drop as (5) BCB- at a ratio of 10:1. After IVM (24 h), oocytes from the different experimental groups were submitted to in vitro fertilisation (IVF) and in vitro culture (IVC) under the same culture conditions until they reached the blastocyst stage (D7). With regards to the cleavage rate (48 h after IVF), only group 3 (102/229 - 44%) differed (P < 0.05) from the other groups [1 (145/241 - 60%); 2 (150/225 - 67%); 4 (201/318 - 63%) and 5 (21/33 - 63%)]. On day 7, the embryos from group 2 (BCB+) achieved the highest blastocyst rate (46/150 - 31%) (P < 0.05) when compared with the embryo development capacity of the other experimental groups (1: 31/145 - 21%; group 3: 17/102 - 17%; group 4: 46/201 - 23%; and group 5: 2/21 - 10%). In conclusion, submitting BCB+ oocytes that were separated from BCB- oocytes to IVM increases the rate of embryonic development to the blastocyst stage when compared to the control group, BCB- oocyte group, BCB+ paracrine group and BCB- paracrine group. The presence of non-competent oocytes during IVM, even in low proportion (1:10), reduces the capacity of competent oocytes to undergo embryo development and achieve blastocyst stage during IVC.

[Not Available]. / Complications non-chirurgicales de la chirurgie bariatrique: à propos de quatre cas et revue de la littérature.

In Belgium and around the world, the weight-control surgery has grown significantly since the beginning of the 21st century. The principal argument in favour of this type of surgery is the expected reduction of the obesity-associated morbidities. However, the expectatif reduction of mortality associated with this kind of surgery is based on a low level of evidence. Besides the mechanical complications, there are a number of health-related problems associated with the post-operative metabolic changes. Authors of the present article have observed four cases presenting with serious affections consecutive to bariatric interventions and reviewed the literature. The most frequent consequence of bariatric surgery is anaemia (15%), which is either due to iron or cyanocobalamine deficiency, followed by neuropathies, bone mineral loss, substance abuse or postprandial hypoglycaemia syndrome. Rare but severe complications are Wernicke's encephalopathy, fulminant hepatitis or hyperoxaluric tubular disease. The prevention, diagnosis and management of these new diseases are becoming a major public health concern.

[Hydrocele]. / Hydrozele.

The hydrocele is overall a rare condition in urology. A differentiation between primary and secondary hydrocele is essential for further treatment. A primary hydrocele with a patent vaginal process tends to spontaneously regress in the first 2 years of life in newborns. If treatment is necessary, open as well as laparoscopic methods are available with good results. The treatment of scrotal pathologies, especially secondary hydrocele, often poses a challenge in the clinical practice. Despite the benign nature, supposedly simple surgical techniques and good chances of healing, postoperative complications are frequent. In comparison to open surgery, sclerotherapy provides a good alternative for the treatment of secondary hydrocele.

Virucidal activity of a plant-oil-based oral rinse against respiratory viruses.

BACKGROUND: Respiratory viruses have been reported to infect the salivary glands and the throat, which are potential reservoirs for virus replication and transmission. Therefore, strategies to reduce the amount of infective virus particles in the oral mucous membranes could lower the risk of transmission. METHODS: The viral inactivation capacity of a plant-oil-based oral rinse (Salviathymol®) was evaluated in comparison with chlorhexidine (Chlorhexamed® FORTE) using a quantitative suspension test according to EN 14476. FINDINGS: Salviathymol efficiently inactivated severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2), respiratory syncytial virus (RSV) and two influenza strains to undetectable levels. CONCLUSION: Salviathymol has potential as preventive measure to lower transmission of respiratory viruses.

[Update on ureteral reconstruction 2024]. / Update Harnleiterrekonstruktion 2024.

Ureteral strictures can occur along the entire course of the ureter and have many different causes. Factors involved in the development include, among other things, congenital anomalies, iatrogenic injuries during endoscopic as well as open or minimally invasive visceral surgical, gynecological, and urological procedures as well as prior radiation therapy. Planning treatment for ureteral strictures requires a detailed assessment of stricture and patient characteristics. Given the various options for ureteral reconstruction, various methods must be considered for each patient. Short-segment proximal strictures and strictures at the pyeloureteral junction are typically surgically managed with Anderson-Hynes pyeloplasty. End-to-end anastomosis can be performed for short-segment proximal and middle ureteral strictures. Distal strictures are treated with ureteroneocystostomy and are often combined with a Boari and/or Psoas Hitch flap. Particularly, the treatment of long-segment strictures in the proximal and middle ureter remain a surgical challenge. The use of bowel interposition is an established treatment option for this, offering good functional results but also potential associated complications. Robot-assisted surgery is increasingly becoming a minimally invasive treatment alternative to reduce hospital stays and optimize postoperative recovery. However, open surgical ureteral reconstruction remains an established procedure, especially after multiple previous abdominal operations.

[Skin manifestations of the external male genitals]. / Hauterscheinungen des männlichen Genitals.

The urological examination includes the inspection of the external male genitals. Harmless normal variants, such as heterotopic sebaceous glands and pearly penile papules must be differentiated from malignant and infectious manifestations. Lichen sclerosus et atrophicus is a frequent connective tissue disease that can lead to functional impairments and an associated high level of suffering for those affected. Both conservative and invasive treatment options are available. Sexually transmitted diseases, such as syphilis, are gaining increasing importance in routine clinical and daily practice due to the increasing incidence in recent years. An early diagnosis and treatment of malignant neoplasms, such as Queyrat's erythroplasia can be carried out by routine inspection of the genital skin.

[Processing of medical products in the urological practice]. / Aufbereitung von Medizinprodukten in der urologischen Praxis.

The reprocessing of medical products is an important topic both in urological practices and in hospitals. The complexity is caused by the increasing variety of medical instruments and also by the increasing demands on the legally required quality of the reprocessing. The Robert Koch Institute (RKI) and the Federal Institute for Drugs and Medical Devices (BfArM) have published recommendations for the processing of MD and last updated them in 2012. This article summarizes the legal framework for the reprocessing of medical devices, how medical devices are categorized before the appropriate procedure for reprocessing can be selected and the various steps in the reprocessing. A special focus is placed on medical products that are typically found in urological practices or outpatient departments and are processed there. Furthermore, the necessity of validating the processing method and the required training (expertise) of the personnel are discussed.