Systems approach in planetary health education for medical students: a mixed methods study.

BACKGROUND: Introducing students to the "planetary health lenses" perspective is crucial. Comprehensive strategies for teaching this perspective are lacking, especially in the domains of "interconnection within nature (IWN)" and "systems thinking/complexity." There is also a scarcity of studies assessing medical students' opinions on planetary health and evaluating teaching strategies. OBJECTIVE: To understand Brazilian medical students' perceptions and knowledge of planetary health (PH) and evaluate the application of the educational material "Patient and Clinic through the Lens of Planetary Health," which addresses "IWN" and "complexity" through the sociological lens of Actor-Network Theory, in an integrative course at a medical school in Brazil. METHODS: A mixed-methods, quasi-experimental design involving two medical student classes during 2022/2023. Participants completed a questionnaire on sociodemographic data; pre- and post-intervention closed-ended questions about perceptions related to PH, and an open-ended questionnaire on experience and learning. Each student group presented a portfolio under the planetary health lenses regarding a real patient, developing a network diagram that described the social network involving both human and non-human actors with which this person is interconnected. The cohorts participated in "IWN" activities: a contemplative trail or reflection on belonging to the planet. RESULTS: Ninety-six students and 9 professors participated. The majority of students (66.7%) reported significant or extremely significant learning from the sessions. There was an increase in perception of the need for physicians to incorporate PH into their clinical practice (p = 0.002; r = 0.46) and an intensification of the sense of interconnection with the environment (p = 0.003; r = 0.46). There was a gain in knowledge about how many diseases were related to PH (p < 0.02 for all 13 listed diseases). The majority (83%) found the sessions relevant or highly relevant and commented on their impact, both professionally and personally. CONCLUSIONS: Teaching PH in a medical school allowed students to learn from the patient's perspective, considering psychosocial and environmental determinants, about the intrinsic interdependence between population's health and PH. This strategy made a significant contribution by proposing pioneering didactics and offering valuable insights into the challenges and nuances of teaching PH.

Analysis of spatial differences in global regional human development index under planetary pressure and decomposition study of driving factors.

To urge nations worldwide to implement robust measures for enhancing human development and mitigating the pressures exerted on the planet by human activities in pursuit of sustainable development, this study encompasses 154 countries globally, using the seven major regions as focal points. Leveraging the Planetary Pressure Adjusted Human Development Index (PHDI) proposed by the United Nations Development Programme on December 15, 2020, as a metric for human development levels, this paper aims to standardize and internationally compare human development data from 1990 to 2021. Subsequently, employing the Theil index, the study assesses the global human development status across the seven regions to analyze spatial disparities in PHDI. Lastly, a comprehensive Generalized Diese Index Method (GDIM) is constructed to accurately reflect absolute and latent factors, dissecting the driving forces impacting global PHDI. The study explores critical pathways for high-quality human development within the harmonious coexistence between humanity and nature. It validates the robustness of GDIM results through a stepwise regression. Research findings indicate varying levels of PHDI development across regions, with a distinct spatial hierarchy evolving: higher human development levels in Europe and Eastern Europe, favorable levels in North and South America, similar levels in Oceania and Asia, and significant improvement potential in Africa. As globalization progresses, overall differences in PHDI gradually decrease; however, disparities persist between and within regions. Economic, technological, and per capita welfare effects consistently positively drive PHDI. In contrast, environmental pressure effects, social effects, per capita value-added effects, and output carbon intensity effects consistently exert hostile driving forces. Population size effects on PHDI show a fluctuating trend. Moreover, in terms of cumulative contribution values, the top three contributors to driving forces are economic, technological, and per capita welfare effects.

A Mission Simulating the Search for Life on Mars with Automated Drilling, Sample Handling, and Life Detection Instruments Performed in the Hyperarid Core of the Atacama Desert, Chile.

We report on a field demonstration of a rover-based drilling mission to search for biomolecular evidence of life in the arid core of the Atacama Desert, Chile. The KREX2 rover carried the Honeybee Robotics 1 m depth The Regolith and Ice Drill for Exploration of New Terrains (TRIDENT) drill and a robotic arm with scoop that delivered subsurface fines to three flight prototype instruments: (1) The Signs of Life Detector (SOLID), a protein and biomolecule analyzer based on fluorescence sandwich microarray immunoassay; (2) the Planetary In Situ Capillary Electrophoresis System (PISCES), an amino acid analyzer based on subcritical water extraction coupled to microchip electrophoresis analysis; and (3) a Wet Chemistry Laboratory cell to measure soluble ions using ion selective electrodes and chronopotentiometry. A California-based science team selected and directed drilling and sampling of three sites separated by hundreds of meters that included a light-toned basin area showing evidence of aqueous activity surrounded by a rocky desert pavement. Biosignatures were detected in basin samples collected at depths ranging from 20 to 80 cm but were not detected in the surrounding area. Subsurface stratigraphy of the units drilled was interpreted from drill sensor data as fine-scale layers of sand/clay sediments interspersed with layers of harder material in the basins and a uniform subsurface composed of course-to-fine sand in the surroundings. The mission timeline and number of commands sent to accomplish each activity were tracked. The deepest sample collected (80 cm) required 55 commands, including drilling and delivery to three instruments. Elapsed time required for drilling and sample handling was less than 3 hours to collect sample from 72 cm depth, including time devoted to recovery from a jammed drill. The experiment demonstrated drilling, sample transfer technologies, and instruments that accomplished successful detection of biomolecular evidence of life in one of the most biologically sparse environments on Earth.

Impact of M Dwarfs Ultraviolet Radiation on Prebiotic Chemistry: The Case of Adenine.

To date, several exoplanets have been found to orbit within the habitable zone of main sequence M stars (M dwarfs). These stars exhibit different levels of chromospheric activity that produces ultraviolet (UV) radiation. UV may be harmful to life, but it can also trigger reactions of prebiotic importance on the surface of a potentially habitable planet (PHP). We created a code to obtain the adenine yield for a known adenine synthesis route from diaminomaleonitrile (DAMN). We used computational methods to calculate the reaction coefficient rates (photolysis rate J and rate constant K) for the intermediate molecules DAMN, diaminofumaronitrile (DAFN), and 4-aminoimidazole-5-carbonitrile (AICN) of the adenine synthesis route. We used stellar UV sources and a mercury lamp to compare the theoretical results with experiments performed with lamps. The surface UV flux of planets in the habitable zone of two active M dwarfs (Proxima Centauri and AD Leonis) and the prebiotic Earth was calculated using the photochemical model ATMOS, considering a CO2-N2-H2O atmosphere. We obtained UV absorption coefficients for DAMN and DAFN and thermodynamic parameters that are useful for prebiotic chemistry studies. According to our results, experiments using UV lamps may underestimate the photolysis production of molecules of prebiotic importance. Our results indicate that photolysis reactions are fast with a yield of 50% of AICN in 10 s for the young Sun and ∼1 h for Proxima Centauri b. Planets around active M dwarfs may provide the most favorable environment for UV-mediated production of compounds relevant to the origins of life. The kinetic reaction AICN + HCN  adenine is the bottleneck of the pathway with reaction rates <10-22 L/(mol·s).

Platelet Transfusions in a Multi-Neonatal Intensive Care Unit Health Care Organization Before and After Publication of the PlaNeT-2 Clinical Trial.

OBJECTIVES: To evaluate whether implementing more restrictive neonatal intensive care unit (NICU) platelet transfusion guidelines following the Platelets for Neonatal Transfusion - Study 2 randomized controlled trial (transfusion threshold changed from 50 000/µL to 25 000/µL for most neonates) was associated with fewer NICU patients receiving a platelet transfusion, without adversely affecting outcomes. STUDY DESIGN: Multi-NICU retrospective analysis of platelet transfusions, patient characteristics, and outcomes during 3 years before vs 3 years after revising system-wide guidelines. RESULTS: During the first period, 130 neonates received 1 or more platelet transfusions; this fell to 106 during the second. The transfusion rate was 15.9/1000 NICU admissions in the first period vs 12.9 in the second (P = .106). During the second period, a smaller proportion of transfusions was administered when the platelet count was in the 50 000-100 000/µL range (P = .017), and a larger proportion when it was <25 000/µL (P = .083). We also saw a fall in the platelet counts that preceded the order for transfusion from 43 100/µL to 38 000/µL (P = .044). The incidence of adverse outcomes did not change. CONCLUSIONS: Changing platelet transfusion guidelines in a multi-NICU network to a more restrictive practice was not associated with a significant reduction in number of neonates receiving a platelet transfusion. The guideline implementation was associated with a reduction in the mean platelet count triggering a transfusion. We speculate that further reductions in platelet transfusions can safely occur with additional education and accountability tracking.

Free-Living Amoebas in Extreme Environments: The True Survival in our Planet.

Free-living amoebas (FLAs) are microorganisms, unicellular protozoa widely distributed in nature and present in different environments, such as water or soil; they are maintained in ecosystems and play a fundamental role in the biological control of bacteria, other protozoa, and mushrooms. In particular circumstances, some can reach humans or animals, promoting several health complications. Notably, FLAs are characterized by a robust capacity to survive in extreme environments. However, currently, there is no updated information on the existence and distribution of this protozoan in inhospitable places. Undoubtedly, the cellular physiology of these protozoan microorganisms is very particular. They can resist and live in extreme environments due to their encysting capacity and tolerance to different osmolarities, temperatures, and other environmental factors, which give them excellent adaptative resistance. In this review, we summarized the most relevant evidence related to FLAs and the possible mechanism, which could explain their adaptative capacity to several extreme environments.

A global network model of abiotic phosphorus cycling on Earth through time.

Phosphorus (P) is a crucial structural component of living systems and central to modern bioenergetics. P cycles through terrestrial geochemical reservoirs via complex physical and chemical processes. Terrestrial life has altered these fluxes between reservoirs as it evolved, which is why it is of interest to explore planetary P flux evolution in the absence of biology. This is especially true, since environmental P availability affects life's ability to alter other geochemical cycles, which could then be an example of niche construction. Understanding how P reservoir transport affects environmental P availability helps parameterize how the evolution of P reservoirs influenced the emergence of life on Earth, and potentially other planetary bodies. Geochemical P fluxes likely change as planets evolve, and element cycling models that take those changes into account can provide insights on how P fluxes evolve abiotically. There is considerable uncertainty in many aspects of modern and historical global P cycling, including Earth's initial P endowment and distribution after core formation and how terrestrial P interactions between reservoirs and fluxes and their rates have evolved over time. We present here a dynamical box model for Earth's abiological P reservoir and flux evolution. This model suggests that in the absence of biology, long term planetary geochemical cycling on planets similar to Earth with respect to geodynamism tends to bring P to surface reservoirs, and biology, including human civilization, tends to move P to subductable marine reservoirs.

Deep learning exoplanets detection by combining real and synthetic data.

Scientists and astronomers have attached great importance to the task of discovering new exoplanets, even more so if they are in the habitable zone. To date, more than 4300 exoplanets have been confirmed by NASA, using various discovery techniques, including planetary transits, in addition to the use of various databases provided by space and ground-based telescopes. This article proposes the development of a deep learning system for detecting planetary transits in Kepler Telescope light curves. The approach is based on related work from the literature and enhanced to validation with real light curves. A CNN classification model is trained from a mixture of real and synthetic data. The model is then validated only with unknown real data. The best ratio of synthetic data is determined by the performance of an optimisation technique and a sensitivity analysis. The precision, accuracy and true positive rate of the best model obtained are determined and compared with other similar works. The results demonstrate that the use of synthetic data on the training stage can improve the transit detection performance on real light curves.

Essential Strategies for School Nurses to Move Upstream in Support of Healthy Students and a Healthy Planet.

Human health is dependent on the health of the planet. Overwhelming evidence indicates that environmental degradation and climate change is negatively affecting planetary health and is on a worsening trajectory. The health of our children, especially those who live in poverty, suffer from chronic disease, or are otherwise disadvantaged, will benefit most from successful efforts to change this trajectory or will suffer the most if we do nothing. School nurses, members of the largest and most trusted group of healthcare providers, have a professional and ethical obligation to address environmental degradation and the impact on our students and communities. Research suggests that knowledge about climate change and the associated health impacts are positively correlated to school nurses' attitudes and behaviors. This article aims to raise school nurse awareness, understanding, and agency regarding the possible trajectories of environmental degradation, implications to the health and well-being of current and future generations of children, and evidence-based actions to positively influence the trajectory. The Framework for 21st Century School Nurse Practice™ advocates a practice model that is student centered and provides a mind-set for school nursing to approach the topic of planetary and environmental health.

A mestizo cosmographer in the New Kingdom of Granada: astronomy and chronology in Sánchez de Cozar Guanientá's Tratado (c.1696).

This article interprets a recently recovered manuscript, Tratado de astronomía y la reformaçión del tiempo, composed by Antonio Sánchez in New Granada c.1696, in the context of the Spanish and Renaissance cosmographies. Sánchez's Tratado proposes a spherical astronomy, in which celestial bodies - including comets - move in orbs containing pyramidal knots that explain the changing speed observed in the motion of planets. From this astronomy and following the peninsular style of repertorios, Sánchez derives two major conclusions: the corrected length of the solar year and a revised birth date of Jesus. Taking as center of reference Vélez, where Sánchez was based, these claims led to conclusions in domains ranging from calendric astronomy to eschatology, including the incorporation of the indigenous peoples into salvation narrative and a demonstration of the arrangement of the celestial orbs at the Last Judgment. Sánchez's Tratado constitutes an expansion of the Spanish mathematical cosmography that sheds light on the production of knowledge in the Spanish-American world and, at the same time, provides elements to reassess our understanding of the global circulation of Renaissance and early modern ideas.

The SiTian Project.

SiTian is an ambitious ground-based all-sky optical monitoring project, developed by the Chinese Academy of Sciences. The concept is an integrated network of dozens of 1-m-class telescopes deployed partly in China and partly at various other sites around the world. The main science goals are the detection, identification and monitoring of optical transients (such as gravitational wave events, fast radio bursts, supernovae) on the largely unknown timescales of less than 1 day; SiTian will also provide a treasure trove of data for studies of AGN, quasars, variable stars, planets, asteroids, and microlensing events. To achieve those goals, SiTian will scan at least 10,000 square deg of sky every 30 min, down to a detection limit of $V \approx 21$ mag. The scans will produce simultaneous light-curves in 3 optical bands. In addition, SiTian will include at least three 4-m telescopes specifically allocated for follow-up spectroscopy of the most interesting targets. We plan to complete the installation of 72 telescopes by 2030 and start full scientific operations in 2032.

Preliminary Results of the Planet Nutrition Program on Obesity Parameters in Mexican Schoolchildren: Pilot Single-School Randomized Controlled Trial.

School-based obesity prevention programs are key to promoting healthy habits. The aim of this study was to evaluate the effect of the Planet Nutrition program on BMI z-score and other parameters compared to a control group of Mexican schoolchildren after 9 weeks of intervention. The effect of the summer holidays on the BMI z-score was also evaluated at 23 weeks. A pilot randomized controlled trial design was used and 41 schoolchildren were randomized (21 intervention group and 20 control). The program included 18 nutrition education sessions, 20 physical activity classes and six brochures for parents. At 9 weeks, no significant differences were found between the intervention and control groups in the change in BMI z-score (-0.11, 95% CI -0.23, 0.01). Significant differences were observed in some secondary outcomes: body fat percentage (-1.72, 95% CI -3.42, -0.02), waist circumference (-3.45, 95% CI -5.55, -1.36), physical activity (0.44, 95% CI 0.01, 0.88) and nutrition knowledge (1.15, 95% CI 0.27, 2.03). Summer holidays negatively affected the BMI z-score in both groups, reducing the difference observed between groups at 9 weeks (-0.07, 95% CI -0.22, 0.07). The Planet Nutrition program showed favorable effects in some obesity and lifestyle parameters in the short term.

Reflected Light from Giant Planets in Habitable Zones: Tapping into the Power of the Cross-Correlation Function.

The direct detection of reflected light from exoplanets is an excellent probe for the characterization of their atmospheres. The greatest challenge for this task is the low planet-to-star flux ratio, which even in the most favourable case is of the order of 10-4 in the optical. This ratio decreases even more for planets in their host's habitable zone, typically lower than 10-7. To reach the signal-to-noise level required for such detections, we propose to unleash the power of the Cross Correlation Function in combination with the collecting power of next generation observing facilities. The technique we propose has already yielded positive results by detecting the reflected spectral signature of 51 Pegasi b (see Martins et al. 2015). In this work, we attempted to infer the number of hours required for the detection of several planets in their host's habitable zone using the aforementioned technique from theoretical EELT observations. Our results show that for 5 of the selected planets it should be possible to directly recover their reflected spectral signature.

Biosignatures as revealed by spectropolarimetry of Earthshine.

Low-resolution intensity spectra of Earth's atmosphere obtained from space reveal strong signatures of life ('biosignatures'), such as molecular oxygen and methane with abundances far from chemical equilibrium, as well as the presence of a 'red edge' (a sharp increase of albedo for wavelengths longer than 700 nm) caused by surface vegetation. Light passing through the atmosphere is strongly linearly polarized by scattering (from air molecules, aerosols and cloud particles) and by reflection (from oceans and land). Spectropolarimetric observations of local patches of Earth's sky light from the ground contain signatures of oxygen, ozone and water, and are used to characterize the properties of clouds and aerosols. When applied to exoplanets, ground-based spectropolarimetry can better constrain properties of atmospheres and surfaces than can standard intensity spectroscopy. Here we report disk-integrated linear polarization spectra of Earthshine, which is sunlight that has been first reflected by Earth and then reflected back to Earth by the Moon. The observations allow us to determine the fractional contribution of clouds and ocean surface, and are sensitive to visible areas of vegetation as small as 10 per cent. They represent a benchmark for the diagnostics of the atmospheric composition, mean cloud height and surfaces of exoplanets.

Astrobiologically interesting stars within 10 parsecs of the sun.

The existence of life based on carbon chemistry and water oceans relies upon planetary properties, chiefly climate stability, and stellar properties, such as mass, age, metallicity, and galactic orbits. The latter can be well constrained with present knowledge. We present a detailed, up-to-date compilation of the atmospheric parameters, chemical composition, multiplicity, and degree of chromospheric activity for the astrobiologically interesting solar-type stars within 10 parsecs of the Sun. We determined their state of evolution, masses, ages, and space velocities, and produced an optimized list of candidates that merit serious scientific consideration by the future space-based interferometry probes aimed at directly detecting Earthsized extrasolar planets and seeking spectroscopic infrared biomarkers as evidence of photosynthetic life. The initially selected stars number 33 solar-type within the total population (excluding some incompleteness for late M-dwarfs) of 182 stars closer than 10 parsecs. A comprehensive and detailed data compilation for these objects is still lacking; a considerable amount of recent data has so far gone unexplored in this context. We present 13 objects as the nearest "biostars," after eliminating multiple stars, young, chromospherically active, hard x-ray- emitting stars, and low metallicity objects. Three of these "biostars"-- Zeta Tucanae, Beta Canum Venaticorum, and 61 Virginis -- closely reproduce most of the solar properties and are considered as premier targets. We show that approximately 7% of the nearby stars are optimally interesting targets for exobiology.