New article published in 12(4A) - ENAN / INAC 2024

A study of a H2O-moderated 241AmBe source for neutron metrology

Abstract: The update to ISO 8529-1 (2021) reduces the variety of neutron fields from sources. For neutron metrology, it is crucial to have a standard radiation field with known fluence and energy well-defined. This study focuses on analyzing new energy ranges and characterizing moderated neutron fields, emphasizing the importance of low-energy neutrons and their impact on dose assessment. Experiments and simulations were conducted with the moderation of the 241AmBe source in light water, enabling the characterization of a new moderated spectrum and the presentation of reference values for physical and radioprotection quantities. This expands the energy options for irradiation and instrument calibration. Read full article

Analysis of the coxal fluid of O. brasiliensis tick species by analytic techniques

Abstract: The coxal fluid of the tick species Ornithodoros brasiliensis (O. brasiliensis) was subjected to detailed chemical analysis using Instrumental Neutron Activation Analysis (INAA) and Energy Dispersive X-ray Fluorescence (EDXRF). These complementary techniques allowed the identification and quantification of key elements such as sodium (Na), chlorine (Cl), potassium (K), and zinc (Zn), along with others like sulfur (S), phosphorus (P), and iron (Fe). The study demonstrated the consistency between the two analytical methods and revealed significant data about the tick's physiological adaptations related to fluid excretion and blood meal processing. Additionally, the absence of heavy metals in the analyzed samples was confirmed. Understanding the composition of coxal fluid is vital for interpreting metabolic processes and exploring its toxicological potential, given the aggressive nature of O. brasiliensis, known to cause severe health impacts on humans and animals. This research contributes to advancing knowledge about tick biology and supports the development of public health measures against tick-borne hazards. Read full article