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The accuracy of reaction theories used to extract properties of exotic nuclei from scattering experiments is often unknown or not quantified, but of utmost importance when, e.g., constraining the equation of state of asymmetric nuclear matter from observables as the neutron-skin thickness. In order to test the Glauber multiple-scattering model, the total interaction cross section of Image 1 on carbon targets was measured at initial beam energies of 400, 550, 650, 800, and 1000 MeV/nucleon. The measurements were performed during the first experiment of the newly constructed R3B (Reaction with Relativistic Radioactive Beams) experiment after the start of FAIR Phase-0 at the GSI/FAIR facility with beam energies of 400, 550, 650, 800, and 1000 MeV/nucleon. The combination of the large-acceptance dipole magnet GLAD and a newly designed and highly efficient Time-of-Flight detector enabled a precise transmission measurement with several target thicknesses for each initial beam energy with an experimental uncertainty of ±0.4%. A comparison with the Glauber model revealed a discrepancy of around 3.1% at higher beam energies, which will serve as a crucial baseline for the model-dependent uncertainty in future fragmentation experiments.

We report the upgrade and operation of a frequency-comb-assisted high-resolution mid-infrared molecular spectrometer, allowing us to combine high spectral purity, International System of Units (SI)-traceability, wide tunability, and high sensitivity. An optical frequency comb is used to transfer the spectral purity of a SI-traceable 1.54 μm metrology-grade frequency reference to a 10.3 μm quantum cascade laser (QCL). The near-infrared reference is operated at the French time/frequency metrology institute, calibrated there to primary frequency standards, and transferred to Laboratoire de Physique des Lasers via the REFIMEVE fiber network. The QCL exhibits a linewidth of δν ∼ 0.1 Hz and a sub-10−15 relative frequency stability from 0.1 to 10 s, and its frequency is traceable to the SI with a total relative uncertainty better than 4 × 10−14 after 1 s averaging time. We have developed the instrumentation allowing comb modes to be continuously tuned over 9 GHz, resulting in a QCL of record spectral purity uninterruptedly tunable at the precision of the reference over an unprecedented span of Δν = 1.4 GHz. We have used our apparatus to conduct sub-Doppler spectroscopy of methanol in a multi-pass cell, demonstrating state-of-the-art frequency uncertainties down to the few kilohertz level (∼10−10 in relative value). We have observed weak intensity resonances unreported so far, resolved subtle doublets never seen before, and brought to light discrepancies with HITRAN. This demonstrates the potential of our apparatus for probing subtle internal molecular processes, building accurate spectroscopic models of polyatomic molecules of atmospheric or astrophysical interest, and carrying out precise spectroscopic tests of fundamental physics.

Agricultural soil erosion, both mechanical and eolic, may impact cloud processes, as some aerosol particles are able to facilitate ice crystal formation. Given the large agricultural sector in Mexico, this study investigates the ice nucleating abilities of agricultural dust collected at different sites and generated in the laboratory. The immersion freezing mechanism of ice nucleation was simulated in the laboratory via the Universidad Nacional Autónoma de México (UNAM) microorifice uniform deposit impactor (MOUDI) droplet freezing technique (DFT), i.e., UNAM-MOUDI-DFT. The results show that agricultural dust from the Mexican territory promote ice formation in the temperature range from −11.8 to −34.5 ∘C, with ice nucleating particle (INP) concentrations between 0.11 and 41.8 L−1. Furthermore, aerosol samples generated in the laboratory are more efficient than those collected in the field, with T50 values (i.e., the temperature at which 50 % of the droplets freeze) higher by more than 2.9 ∘C. Mineralogical analysis indicated a high concentration of feldspars, i.e., K-feldspar and plagioclase (>40 %), in most of the aerosol and soil samples, with K-feldspar significantly correlated with the T50 of particles with aerodynamic diameters between 1.8 and 3.2 µm. Similarly, the organic carbon (OC) was correlated with the ice nucleation efficiency of aerosol samples from 3.2 to 5.6 and from 1.0 to 1.8 µm. Finally, a decrease in INP efficiency after heating the samples at 300 ∘C for 2 h indicates that the organic matter from agricultural soils plays a predominant role in the ice nucleating abilities of this type of aerosol sample.

Proton radioactivity is useful for studying nuclear structure. Here the authors report two proton emission branches from the 10+ state isomer of 54mNi by using a time projection chamber.

Proton-emission branches of the 10+ isomer in the Tz=−1 nucleus 54Ni have been imaged with the active target and time projection chamber (ACTAR TPC) in an experiment conducted at the Grand Accélérateur National d'Ions Lourds (GANIL). The completed decay scheme allows derivation of the reduced transition strengths, B(E2;10+→8+) and B(E4;10+→6+), for the two competing γ-ray transitions. By means of a comparison with their well-known ‘mirror transitions’ in Tz=+1 54Fe, and aided by a variety of shell-model calculations in the fp model space, effective charges for E4 transitions near N=Z 56Ni can be deduced: επ≈1.40 and εν≈0.30. Mirror-energy differences are explored with various shell-model interactions and isospin-symmetry breaking terms.

Most precipitation from deep clouds over the continents and in the intertropical convergence zone is strongly influenced by the presence of ice crystals whose formation requires the presence of ice nucleating particles (INPs). Although there are a large number of INP sources, the ice nucleating abilities of aerosol particles originating from oceans, deserts, and wildfires are poorly described at tropical latitudes. To fill this gap in knowledge, the National Autonomous University of Mexico micro-orifice uniform deposit impactor droplet freezing technique (UNAM-MOUDI-DFT) was constructed to measure the ice nucleating activity of aerosol samples that were collected in Sisal and Mérida, Yucatán (Mexico) under the influence of cold fronts, biomass burning (BB), and African dust (AD) intrusions during five short-term field campaigns between January 2017 and July 2018. The three different aerosol types were distinguished by their physicochemical properties. Marine aerosol (MA), BB, and AD air masses were found to contain INPs; the highest concentrations were in AD (from 0.071 to 36.07 L−1 at temperatures between −18 and −27 ∘C), followed by MA (from 0.068 to 18.90 L−1 at temperatures between −15 and −28 ∘C) and BB (from 0.063 to 10.21 L−1 at temperatures between −20 and −27 ∘C). However, MA had the highest surface active site densities (ns) between −15 and −30 ∘C. Additionally, supermicron particles contributed more than 72 % of the total INP concentration independent of aerosol type.

On a global scale, African dust is known to be one of the major sources of mineral dust particles, as these particles can be efficiently transported to different parts of the planet. Several studies have suggested that the Yucatán Peninsula could be influenced by such particles, especially in July, associated with the strengthening of the Caribbean low-level jet. Although these particles have the potential to significantly impact the local air quality, as shown elsewhere (especially with respect to particulate matter, PM), the arrival and impact of African dust in Mexican territory has not been quantitatively reported to date. Two short-term field campaigns were conducted to confirm the arrival of African dust on the Yucatán Peninsula in July 2017 and July 2018 at the Mérida atmospheric observatory (20.98∘ N, 89.64∘ W). Aerosol particles were monitored at ground level using different online and off-line sensors. Several PM2.5 and PM10 peaks were observed during both sampling periods, with a relative increase in the PM levels ranging between 200 % and 500 % with respect to the normal background conditions. Given that these peaks were found to be highly correlated with supermicron particles and chemical elements typically found in mineral dust particles, such as Al, Fe, Si, and K, they are linked with African dust. This conclusion is supported by combining back trajectories with vertical profiles from radiosondes, reanalysis, and satellite images to show that the origin of the air masses arriving at Mérida was the Saharan Air Layer (SAL). The good agreement found between the measured PM10 concentrations and the estimated dust mixing ratio content from MERRA-2 (Version 2 of the Modern-Era Retrospective analysis for Research and Applications) corroborates the conclusion that the degradation of the local (and likely regional) air quality in Mérida is a result of the arrival of African dust.

The football ascidian Diazona violacea was observed in three different sites in the Aeolian Archipelago (Southern Tyrrhenian Sea), from 53 to 116 m depth. A large population of this ascidian was found on rocky habitat, enhancing its three-dimensionality and constituting a peculiar facies. Colonies of D. violacea showed a mean density of 0.87 ± 0.09 colonies m−2 and a maximum of 4 colonies m−2. The number of zooids was used as a proxy of colony size and age (assuming that the higher the number of zooids, the larger and older is the colony), and the population showed a leptokurtic distribution with the dominant presence of colonies with fewer than 100 zooids. Large aggregations of this species proved to play an important role in terms of seabed complexity, influencing the underwater landscape and worth of being recognized as a relevant type of biogenic habitat (although ephemeral) that can characterize mesophotic rocks in the Mediterranean Sea.

The quasi-free scattering reactions 11C(p,2p) and 10,11,12C(p,pn) have been studied in inverse kinematics at beam energies of 300–400 MeV/u at the R3B-LAND setup. The outgoing proton-proton and proton-neutron pairs were detected in coincidence with the reaction fragments in kinematically complete measurements. The efficiency to detect these pairs has been obtained from GEANT4 simulations which were tested using the 12C(p,2p) and 12C(p,pn) reactions. Experimental cross sections and momentum distributions have been obtained and compared to DWIA calculations based on eikonal theory. The new results reported here are combined with previously published cross sections for quasi-free scattering from oxygen and nitrogen isotopes and together they enable a systematic study of the reduction of single-particle strength compared to predictions of the shell model over a wide neutron-to-proton asymmetry range. The combined reduction factors show a weak or no dependence on isospin asymmetry, in contrast to the strong dependency reported in nucleon-removal reactions induced by nuclear targets at lower energies. However, the reduction factors for (p,2p) are found to be 'significantly smaller than for (p,pn) reactions for all investigated nuclei. Keywords: Quasi-free scattering, Inverse kinematics, Shell model, Spectroscopic factors

Atmospheric aerosol particles that can nucleate ice are referred to as ice-nucleating particles (INPs). Recent studies have confirmed that aerosol particles emitted by the oceans can act as INPs. This very relevant information can be included in climate and weather models to predict the formation of ice in clouds, given that most of them do not consider oceans as a source of INPs. Very few studies that sample INPs have been carried out in tropical latitudes, and there is a need to evaluate their availability to understand the potential role that marine aerosol may play in the hydrological cycle of tropical regions. This study presents results from the first measurements obtained during a field campaign conducted in the tropical village of Sisal, located on the coast of the Gulf of Mexico of the Yucatan Peninsula in Mexico in January–February 2017, and one of the few data sets currently available at such latitudes (i.e., 21∘ N). Aerosol particles sampled in Sisal are shown to be very efficient INPs in the immersion freezing mode, with onset freezing temperatures in some cases as high as −3 ∘C, similarly to the onset temperature from Pseudomonas syringae. The results show that the INP concentration in Sisal was higher than at other locations sampled with the same type of INP counter. Air masses arriving in Sisal after the passage of cold fronts have surprisingly higher INP concentrations than the campaign average, despite their lower total aerosol concentration. The high concentrations of INPs at warmer ice nucleation temperatures (T>-15 ∘C) and the supermicron size of the INPs suggest that biological particles may have been a significant contributor to the INP population in Sisal during this study. However, our observations also suggest that at temperatures ranging between −20 and −30 ∘C mineral dust particles are the likely source of the measured INPs.

This study reports the in situ observations of a deep-sea ascidian, Dicopia antirrhinum (family Octacnemidae), on the deep seabed off the Aeolian Islands (Tyrrhenian Sea), between 569 and 813 m depth. These observations represent the first record of the species in Italian waters and the second observation in vivo to date. Peculiar macroscopic features are described here and the main differences from other species of the family Octacnemidae are highlighted, in order to allow the future identification of D. antirrhinum through visual technologies such as remotely operated vehicles. A total of 29 specimens were observed, with a maximum density of 0.012 specimens/m2. The global geographic and bathymetric distribution of D. antirrhinum known so far is also updated and discussed.

The evolution of the traditional nuclear magic numbers away from the valley of stability is an active field of research. Experimental efforts focus on providing key spectroscopic information that will shed light into the structure of exotic nuclei and understanding the driving mechanism behind the shell evolution. In this work, we investigate the Z=6 spin-orbit shell gap towards the neutron dripline. To do so, we employed NA(p,2p)CA−1 quasi-free scattering reactions to measure the proton component of the 21+ state of 16,18,20C. The experimental findings support the notion of a moderate reduction of the proton 1p1/2−1p3/2 spin-orbit splitting, at variance to recent claims for a prevalent Z=6 magic number towards the neutron dripline.

Isobaric single charge-exchange reactions, changing nuclear charges by one unit but leaving the mass partitions unaffected, have been for the first time investigated by peripheral collisions of 112Sn ions accelerated up to 1A GeV at the GSI facilities. The high-resolving power of the FRS spectrometer allows us to obtain (p,n)-type isobaric charge-exchange cross sections with an uncertainty of 3.5% and to separate quasi-elastic and inelastic components in the missing-energy spectra of the ejectiles. The inelastic component is associated to the excitation of the Δ(1232) isobar resonance and the emission of pions in s-wave both in the target and projectile nucleus, while the quasi-elastic contribution is associated to the nuclear spin-isospin response of nucleon-hole excitations. An apparent shift of the Δ-resonance peak of ∼63 MeV is observed when comparing the missing-energy spectra obtained from the measurements with proton and carbon targets. A detailed analysis, performed with a theoretical model for the reactions, indicates that this observation can be simply interpreted as a change in the relative magnitude between the contribution of the excitation of the resonance in the target and in the projectile.

The Malignant Fibrous Histiocytoma is a very rare cancer and rather exceptional when located in bladder diverticulum. it occurs in men in their sixties, manifests itself through haematuria and/or irritative micturition. There is not a causal association. An immunohistochemical analysis is necessary to establish a differential diagnosis. It is aggressive, with a high rate of local recurrence and remote progression, thereby requiring early treatment that consists of radical cystectomy with pelvic lymph node dissection followed by adjuvant therapy, predominantly radiotherapy on the surgical wound. Close follow-up is crucially important. Poor survival rate even when patients undergo multimodal therapy.

The proton-removal mechanism of the 12C→11B reaction induced on a carbon target via elementary nucleon-nucleon scattering is investigated in exclusive triple-coincidence measurements. The observed two-nucleon angular correlations are found to be consistent with quasi-free scattering of a projectile-like proton off a target-like nucleon. Exclusive cross sections for one-step pp and pn interactions are determined as σpp=17.2(12) mb and σpn=18.2(18), respectively. The extracted quasi-free component amounts up to 58(4)% of the total proton-removal cross section. The results are compared to total proton-removal cross sections obtained from the experiment and eikonal reaction theory. Keywords: Direct nuclear reactions, One-nucleon removal, Quasi-free scattering, Cross sections

A 35-year-old male patient was admitted to our hospital for urachal carcinoma with oligometastatic bone disease. He received a surgical resection through the umbilical area, urachal ligament and bladder dome (partial cystectomy) and adjuvant chemotherapy based on cisplatin-gemcitabine regimens together zoledronic acid with a good tolerance, no toxicity. Nine months after surgery, our patient presented no symptoms and the metastasis had been brought under control with no apparent signs of recurrence as assessed in a follow-up CT. To our knowledge, is the first case report of a urachal carcinoma with oligometastatic bone disease who received multimodal therapy, including surgery resection. Keywords: Urachus Carcinoma, Metastatic, Multimodal Treatment

Quasi-free scattering reactions of the type (p,2p) were measured for the first time exclusively in complete and inverse kinematics, using a 12C beam at an energy of ∼400 MeV/u as a benchmark. This new technique has been developed to study the single-particle structure of exotic nuclei in experiments with radioactive-ion beams. The outgoing pair of protons and the fragments were measured simultaneously, enabling an unambiguous identification of the reaction channels and a redundant measurement of the kinematic observables. Both valence and deeply-bound nucleon orbits are probed, including those leading to unbound states of the daughter nucleus. Exclusive (p,2p) cross sections of 15.8(18) mb, 1.9(2) mb and 1.5(2) mb to the low-lying 0p-hole states overlapping with the ground state (3/2−) and with the bound excited states of 11B at 2.125 MeV (1/2−) and 5.02 MeV (3/2−), respectively, were determined via γ-ray spectroscopy. Particle-unstable deep-hole states, corresponding to proton removal from the 0s-orbital, were studied via the invariant-mass technique. Cross sections and momentum distributions were extracted and compared to theoretical calculations employing the eikonal formalism. The obtained results are in a good agreement with this theory and with direct-kinematics experiments. The dependence of the proton–proton scattering kinematics on the internal momentum of the struck proton and on its separation energy was investigated for the first time in inverse kinematics employing a large-acceptance measurement.

Resumen: Los sistemas irreversibles han sido poco estudiados en el marco de la teoría de control, a pesar de que una de las aplicaciones relevantes de los mismos es el control de los procesos por lotes, los cuales son irreversibles. Por lo tanto, en este artículo se propone un método para analizar la controlabilidad de estado de estos sistemas mediante la teoría de conjuntos, extensible también a los procesos por lotes. Para ello, se proponen las definiciones de Conjunto Reversible y Conjunto de Trayectorias Controlables, ambas para sistemas no lineales; este último conjunto permite el análisis de controlabilidad de estado de los sistemas irreversibles. Adicionalmente, se propone un algoritmo que permite calcular dichos conjuntos desde el conocimiento de la dinámica del sistema. La propuesta es aplicada a un problema de referencia de un proceso por lotes, con lo cual se obtienen resultados de simulación que evidencian las ventajas de la misma para analizar cuantitativamente la controlabilidad de estado de los sistemas irreversibles. Abstract: The irreversible systems have been little studied within the control theory framework, although one of their relevant cases is the batch process control problem. Therefore, in this work a method for analysing state controllability of irreversible systems is proposed. The method uses set theory and its extension to batch processes. Definitions for Reversible Set and Controllable Trajectories Set, both for nonlinear systems, are given in order to analyze state controllability for irreversible systems. Additionally, an algorithm for calculating mentioned sets from the dynamic process knowledge is proposed. The proposal is applied to a batch process benchmark. Obtained simulation results demonstrate the advantages of that proposal to analyze the state controllability of irreversible systems. Palabras clave: Controlabilidad, Reversibilidad, Sistemas irreversibles, Procesos por lotes, Keywords: Controllability, reversible systems, batch control.

Resumen: El número de fluidización (N f ) indica la calidad de la fluidización de un lecho fluidizado, por lo tanto es una variable importante pero difícil, sino imposible, de medir directamente. En este trabajo se propone una estructura de estimación de estado y control del N f para un gasificador de carbón en lecho fluidizado. La estructura de estimación se basa en un modelo del proceso, ecuaciones complementarias y la combinación de estimadores de estado clásicos, lo cual permite reconstruir el N f con la información de otras variables directamente medibles. Con base en el estimador diseñado se proponen lazos de control realimentado para el N f y para la concentración de hidrógeno. El esquema completo se prueba mediante simulación ante cambios en los parámetros del modelo, las entradas al proceso y las referencias de los controladores generando resultados totalmente satisfactorios. Abstract: Fluidization number (N f ) is an index of fluidization quality, therefore it is a critical variable. However, this variable has not a direct measurement. In this work a structure of estimation state and control of N f is propossed for a coal gasifier in a pressurized fluidized bed. The proposed estimation structure is based on process model, complementary equations, and the combination of classic estimators in order to obtain the N f based on the information of other directly mesaured variables. Based on designed estimator, control loops for N f and hydrogen concentration are proposed. The full structure is analized with changes in inputs and set points, finding totally corrects results. Palabras clave: Modelamiento, Observabilidad, Estimadores, Observadores, Control de procesos, Keywords: Modelling, Observability, State estimation, Observers, Process control