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Absolute single photoionization cross-sections of Br3+: Experiment and theory
Absolute single photoionization cross section measurements for Br3+ ions are reported in the photon energy range 44.79-59.54 eV at a photon energy resolution of 21 ±3 meV. Measurements were performed at the Advanced Light Source at Lawrence Berkeley National Laboratory using the merged-beams technique. Numerous resonance features in the experimental spectrum are assigned and their energies and quantum defect values are tabulated. The cross-section measurements are also compared with Breit-Pauli R-matrix calculations with suitable agreement over the photon energy range investigated. Analysis of the measured spectrum including Rydberg resonance series identifications produced a new emperical determination of the ionizational potential of Br3+ of 46.977 ± 0.050 eV, which is 805 meV lower than the most recently published value of 47.782 eV. This disparity between our determination and the earlier published value is similar to an 843 meV shift in the accepted ionization potential published for iso-electronic Se2+ as part of this same research program
The Role of Echocardiography in Neonates and Pediatric Patients on Extracorporeal Membrane Oxygenation
Indications for extracorporeal membrane oxygenation (ECMO) and extracorporeal cardiopulmonary resuscitation (ECPR) are expanding, and echocardiography is a tool of utmost importance to assess safety, effectiveness and readiness for circuit initiation and separation. Echocardiography is key to anticipating complications and improving outcomes. Understanding the patient's as well as the ECMO circuit's anatomy and physiology is crucial prior to any ECMO echocardiographic evaluation. It is also vital to acknowledge that the utility of echocardiography in ECMO patients is not limited to the evaluation of cardiac function, and that clinical decisions should not be made exclusively upon echocardiographic findings. Though echocardiography has specific indications and applications, it also has limitations, characterized as: prior to and during cannulation, throughout the ECMO run, upon separation and after separation from the circuit. The use of specific and consistent echocardiographic protocols for patients on ECMO is recommended
Aumentando la resiliencia climática en el occidente de Honduras: explorando fuentes de agua para pequeños productores rurales
First insights into the archaeometric analysis of the Los Amores Mosaic in Cástulo (Linares, Spain) : the Judgement of Paris
This paper discusses results obtained from in situ analysis of the tesserae of the Roman mosaic of Los Amores (Castulo site, Linares, Spain) dating back to the turn of the 1st to the 2nd century AD. Specifically, it focuses on the scene The Judgment of Paris. In view of the exceptional state of preservation of the mosaic, from which very few tesserae had fallen off, non-invasive methods with portable Micro Raman Spectroscopy (MRS) and hand-held X-ray fluorescence (hXRF) and data assessment by use of principal component analysis and binary representations were selected. The results obtained allow to evaluate both the analytical method and the portable equipment used, as well as to classify the raw materials, the colouring agents and the opacifiers used. MRS analysis proved crucial for the identification of stone tesserae (ironstones, carbonate and siliciclastic rocks) and for the identification of the type of glasses used (soda-lime-silicate and lead type glasses) based on the analysis of two detached tesserae. hXRF analysis of the glass tesserae identified both colouring agents (Co, Cu, Pb, Zn) and opacifiers (calcium antimonate). The data obtained lend themselves to an assessment of the degradation process that threaten the integrity of the mosaic. The identification of tessera made of specific stone materials (especially ironstone) and of lead glass tesserae suggest the existence of a mosaic workshop in the Upper Guadalquivir (Eastern Andalusia, Spain)
Chromosome Studies of Brazilian Ferns
Chromosome numbers, habitat and general geographic distributions are reported for a sample of ferns from the vicinity of Manaus. These numbers are compared with those reported for species in other regions. The report of n=ca. 154 for Schizaea incurvata is the first record of the genus in the American tropics and the others are first counts of these species in continental South America. In Lindsaea n=42 and n=ca. 84, are somewhat lower and appear to represent a line distinct from the species of the paleotropics with n=47. In Trichomanes n=32, 64 and 128 appear to be levels of polyploidy based on X=8, while n = 72 is possibly based on X=9 and suggest possible diverse lines in the genus. Pityrogramma calomelanos with n=116 is considered as an octoploid based on X=29. Our sample covering about ten percent of the pteridophytes in the area we collected, yielded numbers ranging between n=32 and n=154, and generally appears to represent high polyploid levels.São apresentados números de cromossomos, habitats e distribuição geral de 11 espécies (4 gêneros) de pteridófitas da região de Manaus. Estas são as primeiras contagens cromossômicas destas espécies na América do Sul. São feitas comparações com números referidos para estes gêneros em outras regiões geográficas. Os números variam entre n=32 e n=154 e parecem representar altos nÃveis de poliploidia
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