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As Earth's atmospheric temperatures and human populations increase, more people are becoming vulnerable to natural and human-induced disasters. This is particularly true in Central America, where the growing human population is experiencing climate extremes (droughts and floods), and the region is susceptible to geological hazards, such as earthquakes and volcanic eruptions, and environmental deterioration in many forms (soil erosion, lake eutrophication, heavy metal contamination, etc.). Instrumental and historical data from the region are insufficient to understand and document past hazards, a necessary first step for mitigating future risks. Long, continuous, well-resolved geological records can, however, provide a window into past climate and environmental changes that can be used to better predict future conditions in the region. The Lake Izabal Basin (LIB), in eastern Guatemala, contains the longest known continental records of tectonics, climate, and environmental change in the northern Neotropics. The basin is a pull-apart depression that developed along the North American and Caribbean plate boundary ∼ 12 Myr ago and contains > 4 km of sediment. The sedimentological archive in the LIB records the interplay among several Earth System processes. Consequently, exploration of sediments in the basin can provide key information concerning: (1) tectonic deformation and earthquake history along the plate boundary; (2) the timing and causes of volcanism from the Central American Volcanic Arc; and (3) hydroclimatic, ecologic, and geomicrobiological responses to different climate and environmental states. To evaluate the LIB as a potential site for scientific drilling, 65 scientists from 13 countries and 33 institutions met in Antigua, Guatemala, in August 2022 under the auspices of the International Continental Scientific Drilling Program (ICDP) and the US National Science Foundation (NSF). Several working groups developed scientific questions and overarching hypotheses that could be addressed by drilling the LIB and identified optimal coring sites and instrumentation needed to achieve the project goals. The group also discussed logistical challenges and outreach opportunities. The project is not only an outstanding opportunity to improve our scientific understanding of seismotectonic, volcanic, paleoclimatic, paleoecologic, and paleobiologic processes that operate in the tropics of Central America, but it is also an opportunity to improve understanding of multiple geological hazards and communicate that knowledge to help increase the resilience of at-risk Central American communities.

This work presents unprecedented, high-resolution palaeomagnetic data from the sedimentary record of Lake Levinson-Lessing, the deepest lake in northern central Siberia. Palaeomagnetic analyses were carried out on 730 discrete samples from the upper 38 m of the 46 m long core Co1401, which was recovered from the central part of the lake. Alternating field demagnetization experiments were carried out to obtain the characteristic remanent demagnetization. The relative palaeointensity is determined using the magnetic susceptibility, the anhysteretic remanent magnetization, and the isothermal remanent magnetization for normalization of the partial natural remanent magnetization. The chronology of Co1401 derives from correlation of the relative palaeointensity of 642 discrete samples with the GLOPIS-75 reference curve, accelerated mass spectrometer radiocarbon ages, and optically stimulated luminescence dating. This study focuses on the part > 10 ka but also presents preliminary results for the younger part of the core. The record includes the geomagnetic excursions Laschamps and Mono Lake and resolves sufficient geomagnetic features to establish a chronology that continuously covers the last ∼ 62 kyr. The results reveal continuous sedimentation at high rates between 45 and 95 cm kyr−1. The low variability of the magnetic record compared to datasets of reference records with lower sedimentation rates may be due to a smoothing effect associated with the lock-in depths. Because Co1401 was cored without core segment overlap the horizontal component of the characteristic remanent magnetization can only be used with caution. Nevertheless, the magnetic record of Co1401 is exceptional as it is the only high-resolution record of relative palaeointensity and palaeosecular variations from the Arctic tangent cylinder going back to ∼ 62 ka.

Os jalecos são um veículo potencial de transmissão microbiológica e seu uso inadequado traz riscos à saúde de profissionais e da população. O objetivo deste estudo foi o de conhecer as práticas de utiliza- ção e o perfil de contaminação dos jalecos brancos usados como uniforme por docentes e discentes do Centro Universitário Serra dos Orgãos (UNIFESO). Trata-se de um estudo quantitativo, transversal e exploratório. Respeitados os princípios éticos, aplicou-se questionário sobre o modo de uso e se realizou a análise microbiológica. Os dados foram analisados de forma manual, expressos em percentuais e demonstrados por meio de tabelas. Como resultado, 73 (setenta e três) jalecos estudados apresentaram variada flora, com predomínio de cocos Gram positivos. A região do punho, a mais contaminada, apresentou em média 23 UFC por campo. Quanto ao perfil de uso, a maioria, 42, (57%) tem idade entre 18 e 25 anos, 46 (63%) são do sexo feminino, 27 (37%) são acadêmicos de medicina do 3o período e apenas 13 (18%) são docentes. Sobre a frequência de troca do jaleco, 35 (48%) trocam uma vez por semana, entretanto com inadequado manuseio. Após uso, 36 (49%) não lavam o jaleco separadamente, 43 (58%) não usam produto desinfetante e 54 (73%) utilizam a passagem a ferro como medida complementar de contenção microbiológica. Conclui-se que há imperiosa necessidade de conscientização dos acadêmicos e docentes sobre adequados uso e manuseio do jaleco e importância da vestimenta na epidemiologia das infecções intra e extra-ambientes da saúde