Experimental studies of nuclear fission induced by fusion, transfer, spallation, fragmentation, and electromagnetic reactions in combination with state-of-the-art calculations are successful to ...investigate the nuclear dissipation mechanism in normal nuclear matter, containing only nucleons. The dissipation mechanism has been widely studied by the use of many different fission observables and nowadays the dissipation coefficients involved in transport theories are well constrained. However, the existence of hypernuclei and the possible presence of hyperons in neutron stars make it necessary to extend the investigation of the nuclear dissipation coefficient to the strangeness sector. In this Letter, we use fission reactions of hypernuclei to constrain for the first time the dissipation coefficient in hypernuclear matter, observing that this coefficient increases a factor of 6 in the presence of a single Λ hyperon with respect to normal nuclear matter.
Spallation and fragmentation reactions at incident energies above the Fermi momentum are considered to be the main mechanism for the production of neutron-rich nuclei at worldwide nuclear physics ...facilities, such as RIBF, FRIB, and GSI-FAIR. Although it is widely known that dynamical reaction models give a rather good prediction of cross sections for nuclear residues produced in spallation and fragmentation reactions, these reaction models fail in the description of peripheral collisions involving short-range nucleon-nucleon correlations (SRCs). Here, we present state-of-the-art dynamical reaction calculations based on the intranuclear cascade approach to describe spallation and fragmentation reactions. The new version of our dynamical model, including SRCs, successfully describes isotopic cross sections of neutron-rich nuclear residues and inclusive single-neutron and single-proton knockout cross sections for various stable and exotic nuclei. Finally, the results show that the systematic strong dependency of the single-knockout cross section reduction factor on the neutron-proton separation energy asymmetry parameter (ΔS) obtained by Tostevin and Gade disappears when SRCs are taken into account.
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•A control system for the continuous flow operation of solar photo-Fenton was designed.•Two micropollutant removal targets were evaluated: 70% and 90%.•Disturbance rejection was ...successfully achieved.•Cost efficiency improvements from 45 to 50% were achieved.•Water treatment capacity was studied over different seasons of the year.
This work presents a control approach for the continuous flow operation of the solar photo-Fenton process in raceway pond reactors designed for micropollutant (MP) removal from urban wastewater treatment plant secondary effluents. The control system was designed using the mechanistic and semiempirical kinetic model of the photo-Fenton process at acidic pH developed and validated in previous work. Afterwards, a simulation study to demonstrate the viability of the control system was conducted under different operating conditions (hydraulic residence time and liquid depth) for solar irradiance and water temperature variation over the year. Two liquid depths (10 and 20 cm) and two hydraulic residence times (15 and 30 min) were selected as operating conditions to study the system performance for different MP removal control setpoints (70 % and 90 %). For 90 % MP removal setpoint, cost efficiency reductions of up to 21 % were reached, which denotes that the process efficiency is significantly influenced by the control setpoint. This is because highly demanding MP removal setpoints are achieved through high non-linear reagent consumption, resulting in low operating cost efficiencies of the process. On the other hand, cost efficiency improvements from 45 to 50 % were achieved when an 70 % MP removal setpoint was adopted, when comparing the manual operation of the process with the automatic mode. The presented results demonstrate not only the feasibility of implementing an automatic approach for the solar photo-Fenton process, but also the need for an optimised, efficient and controlled operation to upgrade its competitiveness versus conventional technologies.
Biodegradability of aqueous solutions of the herbicide alachlor and the fungicide pyrimethanil, partly treated by photo-Fenton, and the effect of photoreaction intermediates on growth and DOC removal ...kinetics of the bacteria
Pseudomonas putida CECT 324 are demonstrated. Toxicity of 30–120
mg
L
−1 alachlor and pyrimethanil has been assayed in
P. putida. The biodegradability of photocatalytic intermediates found at different photo-treatment times was evaluated for each pesticide. At a selected time during batch-mode phototreatment, larger-scale biodegradation kinetics were analysed in a 12
L bubble column bioreactor. Both alachlor and pyrimethanil are non-toxic for
P. putida CECT 324 at the test concentrations, but they are not biodegradable. A ∼100
min photo-Fenton pre-treatment was enough to enhance biodegradability, the biological oxidation response being dependent on the pesticide tested. The different alachlor and pyrimethanil respiration and carbon uptake rates in pre-treated solutions are related to change in the growth kinetics of
P. putida. Reproducible results have shown that
P. putida could be a suitable microorganism for determining photo-Fenton pre-treatment time.
Stir bar sorptive extraction (SBSE) has generated growing interest due to its high effectiveness for the extraction of non-polar and medium-polarity compounds from liquid samples or liquid extracts. ...In particular, in recent years, a large amount of new analytical applications of SBSE has been proposed for the extraction of natural compounds, pollutants and other organic compounds in foods, biological samples, environmental matrices and pharmaceutical products. The present review summarizes and discusses the theory behind SBSE and the most recent developments concerning its effectiveness. In addition, the main results of recent analytical approaches and their applications, published in the last three years, are described. The advantages, limitations and disadvantages of SBSE are described and an overview of future trends and novel extraction sorbents and supports is given.
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•Summary of the most important aspect for the development of a robust method based on SBSE.•Review of the latest applications in analytical chemistry employing SBSE.•Review of the unresolved limitations and issues of SBSE.•Present and future trends in SBSE are discussed.
The influence of pesticide concentration, expressed as dissolved organic carbon (DOC), on combined solar photo-Fenton and biological oxidation treatment was studied using wastewater containing a ...mixture of five commercial pesticides, Vydate, Metomur, Couraze, Ditumur and Scala. Two initial DOC concentrations, 200
mg
L
−1 and 500
mg
L
−1 were assayed. Variation in biodegradability with photocatalytic treatment intensity was tested using
Pseudomonas putida. Thus the mineralisation required for combining with biodegradation of intermediates by activated sludge was 33% and 55% at 200
mg
L
−1 and 500
mg
L
−1, respectively. Biotreatment was carried out in a stirred tank in sequencing batch reactor (SBR) mode. As revealed by the biodegradation kinetics, intermediates generated at the higher pesticide concentration caused lower carbon removal rates in spite of the longer photo-Fenton treatment time applied. One strategy for treating water with high concentrations of pesticides and overcoming the low biodegradability of photo-Fenton intermediates is to mix it with a biodegradable carbon source before biological oxidation. This combination of photo-Fenton and acclimatized activated sludge in several SBR cycles led to complete biodegradation of a concentrated pesticide solution of 500
mg
L
−1 DOC in ∼5
h with a carbon removal efficiency of 90%.
Background
COVID‐19 pandemic causes high global morbidity and mortality and better medical treatments to reduce mortality are needed.
Objective
To determine the added benefit of cyclosporine A (CsA), ...to low‐dose steroid treatment, in patients with COVID‐19.
Methods
Open‐label, non randomized pilot study of patients with confirmed infection of SARS‐CoV‐2 hospitalized from April to May 2020 at a single centre in Puebla, Mexico. Patients were assigned to receive either steroids or CsA plus steroids. Pneumonia severity was assessed by clinical, laboratory, and lung tomography. The death rate was evaluated at 28 days.
Results
A total of 209 adult patients were studied, 105 received CsA plus steroids (age 55.3 ± 13.3; 69% men), and 104 steroids alone (age 54.06 ± 13.8; 61% men). All patients received clarithromycin, enoxaparin and methylprednisolone or prednisone up to 10 days. Patient's death was associated with hypertension (RR = 3.5) and diabetes (RR = 2.3). Mortality was 22 and 35% for CsA and control groups (P = 0.02), respectively, for all patients, and 24 and 48.5% for patients with moderate to severe disease (P = 0.001). Higher cumulative clinical improvement was seen for the CsA group (Nelson Aalen curve, P = 0.001, log‐rank test) in moderate to severe patients. The Cox proportional hazard analysis showed the highest HR improvement value of 2.15 (1.39–3.34, 95%CI, P = 0.0005) for CsA treatment in moderate to severe patients, and HR = 1.95 (1.35–2.83, 95%CI, P = 0.0003) for all patients.
Conclusion
CsA used as an adjuvant to steroid treatment for COVID‐19 patients showed to improve outcomes and reduce mortality, mainly in those with moderate to severe disease. Further investigation through controlled clinical trials is warranted.
Taking benefit of the R3B/SOFIA setup to measure the mass and the nuclear charge of both fission fragments in coincidence with the total prompt-neutron multiplicity, the scission configurations are ...inferred along the thorium chain, from the asymmetric fission in the heavier isotopes to the symmetric fission in the neutron-deficient thorium. Against all expectations, the symmetric scission in the light thorium isotopes shows a compact configuration, which is in total contrast to what is known in the fission of the heavier thorium isotopes and heavier actinides. This new main symmetric scission mode is characterized by a significant drop in deformation energy of the fission fragments of about 19 MeV, compared to the well-known symmetric scission in the uranium-plutonium region.
Percutaneous treatment of patent ductus arteriosus (PDA) in extreme premature infants is technically difficult, and therefore, often not consider as an alternative to surgery. The main objective of ...our work was to compare respiratory status prior and post ductal closure and morbi-mortality, in our series of preterm infants with percutaneous PDA closure versus surgical ligation in the same time-period. Retrospective review of all premature infants submitted to percutaneous and surgical PDA closure from January 2011 to December 2016. All the antenatal, perinatal, and postnatal characteristics were collected. The main outcome was the assessment of the pulmonary status before and after ductal closure using a pulmonary score. Secondary outcomes included moderate-severe disability in neurodevelopment, death before discharge, moderate-severe chronic lung disease, and morbidity at discharge. 25 patients with a mean weight of 1330 g (± 280) underwent percutaneous closure of PDA with ADO-II-AS, and a total of 53 underwent surgical ligation. 28/53 with similar gestational age, birth weight, and procedure weight to those in the percutaneous group, were selected to perform the comparative study. Ductal closure (percutaneous and surgical) resulted in improved respiratory status. However, percutaneous group achieved a fastest respiratory improvement, than surgical group. The surgical closure group associated higher morbidity among survivors (HIV, number of sepsis, need, and duration of inotropics post-interventionism). The incidence of recurrent laryngeal nerve palsy among the surgical group was 17%. Percutaneous closure of PDA in carefully selected low-weight preterm infants is a safe and reliable alternative to surgical ligation.
We compared the effects of two resistance training (RT) programs only differing in the repetition velocity loss allowed in each set: 20% (VL20) vs 40% (VL40) on muscle structural and functional ...adaptations. Twenty‐two young males were randomly assigned to a VL20 (n = 12) or VL40 (n = 10) group. Subjects followed an 8‐week velocity‐based RT program using the squat exercise while monitoring repetition velocity. Pre‐ and post‐training assessments included: magnetic resonance imaging, vastus lateralis biopsies for muscle cross‐sectional area (CSA) and fiber type analyses, one‐repetition maximum strength and full load‐velocity squat profile, countermovement jump (CMJ), and 20‐m sprint running. VL20 resulted in similar squat strength gains than VL40 and greater improvements in CMJ (9.5% vs 3.5%, P < 0.05), despite VL20 performing 40% fewer repetitions. Although both groups increased mean fiber CSA and whole quadriceps muscle volume, VL40 training elicited a greater hypertrophy of vastus lateralis and intermedius than VL20. Training resulted in a reduction of myosin heavy chain IIX percentage in VL40, whereas it was preserved in VL20. In conclusion, the progressive accumulation of muscle fatigue as indicated by a more pronounced repetition velocity loss appears as an important variable in the configuration of the resistance exercise stimulus as it influences functional and structural neuromuscular adaptations.
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