Human Space Research Articles

Reduced ossification caused by 3D simulated microgravity exposure is short-term in larval zebrafish

Understanding how skeletal tissues respond to microgravity is ever more important with the increased interest in human space travel. Here, we exposed larval Danio rerio at 3.5 dpf to simulated microgravity (SMG) using a 3D mode of rotation in a ground-based experiment and then studied different cellular, molecular, and morphological bone responses both immediately after exposure and one week later. Our results indicate an overall decrease in ossification in several developing skeletal elements immediately after SMG exposure with the exception of the otoliths, however ossification returns to normal levels seven days after exposure. Coincident with the reduction in overall ossification tnfsf11 (RANKL) expression is highly elevated after 24 h of SMG exposure and also returns to normal levels seven days after exposure. We also show that genes associated with osteoblasts are unaffected immediately after SMG exposure. Thus, the observed reduction in ossification is primarily the result of a high level of bone resorption. This study sheds insight into the nuances of how osteoblasts and osteoclasts in the skeleton of a vertebrate organism respond to an external environmental disturbance, in this case simulated microgravity.

Negotiating the authenticity of AI: how the discourse on AI rejects human indeterminacy

AbstractIn this paper, we demonstrate how the language and reasonings that academics, developers, consumers, marketers, and journalists deploy to accept or reject AI as authentic intelligence has far-reaching bearing on how we understand our human intelligence and condition. The discourse on AI is part of what we call the “authenticity negotiation process” through which AI’s “intelligence” is given a particular meaning and value. This has implications for scientific theory, research directions, ethical guidelines, design principles, funding, media attention, and the way people relate to and act upon AI. It also has great impact on humanity’s self-image and the way we negotiate what it means to be human, existentially, culturally, politically, and legally. We use a discourse analysis of academic papers, AI education programs, and online discussions to demonstrate how AI itself, as well as the products, services, and decisions delivered by AI systems are negotiated as authentic or inauthentic intelligence. In this negotiation process, AI stakeholders indirectly define and essentialize what being human(like) means. The main argument we will develop is that this process of indirectly defining and essentializing humans results in an elimination of the space for humans to be indeterminate. By eliminating this space and, hence, denying indeterminacy, the existential condition of the human being is jeopardized. Rather than re-creating humanity in AI, the AI discourse is re-defining what it means to be human and how humanity is valued and should be treated.

Reduced Pseudomonas aeruginosa Cell Size Observed on Planktonic Cultures Grown in the International Space Station.

Bacterial growth and behavior have been studied in microgravity in the past, but little focus has been directed to cell size despite its impact on a myriad of processes, including biofilm formation, which is impactful regarding crew health. To interrogate this characteristic, supernatant aliquots of P. aeruginosa cultured on different materials and media on board the International Space Station (ISS) as part of the Space Biofilms Project were analyzed. For that experiment, P. aeruginosa was grown in microgravity-with matching Earth controls-in modified artificial urine medium (mAUMg-high Pi) or LB Lennox supplemented with KNO3, and its formation of biofilms on six different materials was assessed. After one, two, and three days of incubation, the ISS crew terminated subsets of the experiment by fixation in paraformaldehyde, and aliquots of the supernatant were used for the planktonic cell size study presented here. The measurements were obtained post-flight through the use of phase contrast microscopy under oil immersion, a Moticam 10+ digital camera, and the FIJI image analysis program. Statistical comparisons were conducted to identify which treatments caused significant differences in cell dimensions using the Kruskal-Wallis and Dunn tests. There were statistically significant differences as a function of material present in the culture in both LBK and mAUMg-high Pi. Along with this, the data were also grouped by gravitational condition, media, and days of incubation. Comparison of planktonic cells cultured in microgravity showed reduced cell length (from 4% to 10% depending on the material) and diameter (from 1% to 10% depending on the material) with respect to their matching Earth controls, with the caveat that the cultures may have been at different points in their growth curve at a given time. In conclusion, smaller cells were observed on the cultures grown in microgravity, and cell size changed as a function of incubation time and the material upon which the culture grew. We describe these changes here and possible implications for human space travel in terms of crew health and potential applications.

Living with Bears in Prahova Valley, Romania: An Integrative Analysis.

Our research focuses on a complex and integrative analysis of bear presence in four tourist resorts in Prahova Valley, Romania: Sinaia, Bușteni, Azuga and Predeal. Employing innovative mixed methods, including questionnaires, interviews, newspaper analysis, and consideration of the local toponymy, including bear-related names and souvenirs, we aim to highlight the extent to which a posthumanist attitude is evident in the region. The sustained appearance of bears is attributed to habitat invasion through deforestation, road construction, residential neighborhoods, and tourist infrastructure. Ambiguity arises from the presence of food sources and voluntary feeding both by locals and tourists. The mass media initially heightened fear and panic during the onset of human-bear interactions but later adopted a more tolerant tone regarding the bear's presence in tourist resorts, reflecting an openness to the posthumanist approach in Prahova Valley. That is why locals express fear and concern about bear encounters, advocating for a clear separation between animal and human spaces. Tourists exhibit attitudes ranging from unconscious appreciation to ambivalence, often contributing to the problem through practices such as feeding bears for fun. The use of bear-related names for tourist establishments is identified as anthropocentric, despite their appeal for attracting tourists. Souvenir sales, through increasing socio-economic value and contributing to tourist experiences, are also recognized as anthropocentric. However, souvenirs can provide elements of support for bear conservation efforts and the equal consideration of human and non-human entities. This study concludes that a successful adaptive coexistence requires a posthumanist vision, overcoming anthropocentrism in a landscape altered by human activities, supported by bear management programs in Bucegi Natural Park, and conservation efforts in Prahova Valley in a landscape altered by people.

The human biology of spaceflight.

To expand the human exploration footprint and reach Mars in the 2030s, we must explore how humans survive and thrive in demanding, unusual, and novel ecologies (i.e., extreme environments). In the extreme conditions encountered during human spaceflight, there is a need to understand human functioning and response in a more rigorous theoretically informed way. Current models of human performance in space-relevant environments and human space science are often operationally focused, with emphasis on acute physiological or behavioral outcomes. However, integrating current perspectives in human biology allows for a more holistic and complete understanding of how humans function over a range of time in an extreme environment. Here, we show how the use of evolution-informed frameworks (i.e., models of life history theory to organize the adaptive pressures of spaceflight and biocultural perspectives) coupled with the use of mixed-methodological toolkits can shape models that better encompass the scope of biobehavioral human adjustment to long-duration space travel and extra-terrestrial habitation. Further, we discuss how we can marry human biology perspectives with the rigorous programmatic structures developed for spaceflight to model other unknown and nascent extremes.

Muscle synergies inherent in simulated hypogravity running reveal flexible but not unconstrained locomotor control

With human space exploration back in the spotlight, recent studies have investigated the neuromuscular adjustments to simulated hypogravity running. They have examined the activity of individual muscles, whereas the central nervous system may rather activate groups of functionally related muscles, known as muscle synergies. To understand how locomotor control adjusts to simulated hypogravity, we examined the temporal (motor primitives) and spatial (motor modules) components of muscle synergies in participants running sequentially at 100%, 60%, and 100% body weight on a treadmill. Our results highlighted the paradoxical nature of simulated hypogravity running: The reduced mechanical constraints allowed for a more flexible locomotor control, which correlated with the degree of spatiotemporal adjustments. Yet, the increased temporal (shortened stance phase) and sensory (deteriorated proprioceptive feedback) constraints required wider motor primitives and a higher contribution of the hamstring muscles during the stance phase. These results are a first step towards improving astronaut training protocols.

Construction of microgravity biological knowledge graph and its applications in anti-osteoporosis drug prediction

Microgravity in the space environment can potentially have various negative effects on the human body, one of which is bone loss. Given the increasing frequency of human space activities, there is an urgent need to identify effective anti-osteoporosis drugs for the microgravity environment. Traditional microgravity experiments conducted in space suffer from limitations such as time-consuming procedures, high costs, and small sample sizes. In recent years, the in-silico drug discovery method has emerged as a promising strategy due to the advancements in bioinformatics and computer technology. In this study, we first collected a total of 184,915 literature articles related to microgravity and bone loss. We employed a combination of dependency path extraction and clustering techniques to extract data from the text. Afterwards, we conducted data cleaning and standardization to integrate data from several sources, including The Global Network of Biomedical Relationships (GNBR), Curated Drug–Drug Interactions Database (DDInter), Search Tool for Interacting Chemicals (STITCH), DrugBank, and Traditional Chinese Medicines Integrated Database (TCMID). Through this integration process, we constructed the Microgravity Biology Knowledge Graph (MBKG) consisting of 134,796 biological entities and 3,395,273 triplets. Subsequently, the TransE model was utilized to perform knowledge graph embedding. By calculating the distances between entities in the model space, the model successfully predicted potential drugs for treating osteoporosis and microgravity-induced bone loss. The results indicate that out of the top 10 ranked western medicines, 7 have been approved for the treatment of osteoporosis. Additionally, among the top 10 ranked traditional Chinese medicines, 5 have scientific literature supporting their effectiveness in treating bone loss. Among the top 20 predicted medicines for microgravity-induced bone loss, 15 have been studied in microgravity or simulated microgravity environments, while the remaining 5 are also applicable for treating osteoporosis. This research highlights the potential application of MBKG in the field of space drug discovery.

Autonomous Detection of Humans in Off-Limits Mountain Areas.

This paper is on the autonomous detection of humans in off-limits mountains. In off-limits mountains, a human rarely exists, thus human detection is an extremely rare event. Due to the advances in artificial intelligence, object detection-classification algorithms based on a Convolution Neural Network (CNN) can be used for this application. However, considering off-limits mountains, there should be no person in general. Thus, it is not desirable to run object detection-classification algorithms continuously, since they are computationally heavy. This paper addresses a time-efficient human detector system, based on both motion detection and object classification. The proposed scheme is to run a motion detection algorithm from time to time. In the camera image, we define a feasible human space where a human can appear. Once motion is detected inside the feasible human space, one enables the object classification, only inside the bounding box where motion is detected. Since motion detection inside the feasible human space runs much faster than an object detection-classification method, the proposed approach is suitable for real-time human detection with low computational loads. As far as we know, no paper in the literature used the feasible human space, as in our paper. The outperformance of our human detector system is verified by comparing it with other state-of-the-art object detection-classification algorithms (HOG detector, YOLOv7 and YOLOv7-tiny) under experiments. This paper demonstrates that the accuracy of the proposed human detector system is comparable to other state-of-the-art algorithms, while outperforming in computational speed. Our experiments show that in environments with no humans, the proposed human detector runs 62 times faster than YOLOv7 method, while showing comparable accuracy.

Long-term simulated microgravity fosters carotid aging-like changes via Piezo1.

Elucidating the impacts of long-term spaceflight on cardiovascular health is urgently needed in face of the rapid development of human space exploration. Recent reports including the NASA Twins Study on vascular deconditioning and aging of astronauts in spaceflight are controversial. The aims of this study were to elucidate whether long-term microgravity promotes vascular aging and the underlying mechanisms. Hindlimb unloading (HU) by tail suspension was used to simulate microgravity in rats and mice. The dynamic changes of carotid stiffness in rats during 8 weeks of HU were determined. Simulated microgravity led to carotid artery aging-like changes as evidenced by increased stiffness, thickness, fibrosis, and elevated senescence biomarkers in the HU rats. Specific deletion of the mechanotransducer Piezo1 in vascular smooth muscles significantly blunted these aging-like changes in mice. Mechanistically, mechanical stretch-induced activation of Piezo1 elevated microRNA-582-5p in vascular smooth muscle cells, with resultant enhanced synthetic cell phenotype and increased collagen deposition via PTEN/PI3K/Akt signalling. Importantly, inhibition of miRNA-582-5p alleviated carotid fibrosis and stiffness not only in HU rats but also in aged rats. Long-term simulated microgravity induces carotid aging-like changes via the mechanotransducer Piezo1-initiated and miRNA-mediated mechanism.

Human Activities and Urban Green Spaces of Slum-Dwelling Areas : A Case of Dandora Estates, Nairobi County

Rapid urbanization, coupled with population influx in many developing countries worldwide, is a prominent cause of the depletion of urban green spaces (UGS). These beautiful, green, and tranquil areas within urban forms are being depleted due to increased human interference in cities and urban areas globally. This paper examines the implications of various human activities that dominate the urban green spaces of Dandora by engaging with household heads and those found undertaking activities within the UGS. The results indicate that residents' participation in social and economic activities had a positive correlation (0.18 and 0.304, respectively) with the negative effects on UGS, while residents' participation in environmental activities had a negative correlation (-0.502) with the latter. The findings establish that the primary positive effect resulting from human activities practiced in the UGS in Dandora was increased UGS users who increased utility and made use of these spaces. Some of the recommendations include: the county government should reclaim and rehabilitate any open space that may have been encroached upon to facilitate other unplanned and haphazard developments. This move will tend to increase the green space size as they originally were, making them more functional, usable, and accessible to the public. The Ministry of Land needs to invest in a centralized land information system and Geographic Information System as a tool in innovative land use planning to reduce encroachments. There is a dire need for architects, engineers, and environmentalists within the country to advise and educate real estate developers on the importance of biophilic design to the contemporary urban form.

INTENTIONALITY AND FUNCTIONAL POTENTIAL OF ENGINEERING THINKING IN THE CONDITIONS OF MODERN MILITARY CHALLENGES

Actual scientific researches and issues analysis. The works of S. Winchester, E. Meyers, K. Mitch, K. Smythe, A. Ustundag, E. Chevikkan, E. Schatzberg, and others are devoted to the study of the role of technology and engineering in the human life space. Axiological and cultural-anthropological aspects of engineering thinking are considered in the works of Ukrainian researchers. First of all, this is the research of V. Voronkova, I. Goliad, I. Markus, and O. Shulga. Discussions about the responsible use of technology in the context of military operations and the creation and development of more peaceful innovations are of particular importance. The statement of basic materials. Philosophy of technology is an important area of study because it examines the impact of technology on human existence, society, and the future of humanity. Technologies have a significant impact on human life and international relations, creating new challenges and fundamental questions about the ethics of their use, the responsibility of developers and users, as well as possible consequences for the future world. Issues related to establishing a balance between technological capabilities and general values of society require special attention. The question of the genesis of the definition of engineering success requires special attention, which can conditionally occur depending on the context where the project is carried out. In peacetime, the success of this project is evaluated according to the criteria of efficiency, economy and innovation, since the task is to improve technologies, optimize processes and ensure sustainable development. Engineering thinking in the conditions of a globalized world and longterm geopolitical claims must be ready for such challenges. First of all, it is about responsibility in ensuring the ethical and safe use of their developments. It is about supporting international efforts to control and regulate the export of military equipment, developing principles and standards for the ethical development and use of technologies for military purposes. In addition, engineers can play an active role in the development of technologies aimed at peaceful purposes and limiting the possibility of using technology in military conflicts. The functional potential of engineering thinking in the creation of state-of-the-art technologies in the conditions of war is specified through the ability to develop, implement and adapt technical solutions capable of responding to complex military challenges. This covers the following aspects: innovativeness, adaptability, cooperation.

Optimizing lunar regolith beneficiation for ilmenite enrichment

Over the past few years, the international space industry has focused extensively on advancing technologies to enable prolonged human space exploration missions. The primary limiting factor for these endeavors is the spacecraft’s capacity to transport and store essential supplies from Earth to support human life and mission equipment throughout the mission’s duration. In-situ resource utilization (ISRU) is the preferred solution for this challenge. Previous lunar missions have identified the presence of oxygen within the lunar regolith, which is an important resource for human space exploration missions. Oxygen is present in many different minerals within the lunar regolith out of which, ilmenite provides the highest yield of oxygen per unit mass using hydrogen reduction. However, the distribution of ilmenite is neither high nor uniform throughout the lunar surface and therefore, needs beneficiation, which is an important intermediate step for ilmenite-based oxygen production. A regolith beneficiation testbed was developed at DLR Bremen which is a TRL 4 level representation of the technology. The testbed has multiple process parameters that can be adjusted to produce the desired feedstock. This work focuses on the optimization of this testbed to produce a feedstock with higher ilmenite content than the input regolith. The testbed comprises three beneficiation techniques, viz. gravitational, magnetic and electrostatic beneficiation that work sequentially to produce the desired feedstock. The optimized parameter configuration achieved up to three-fold increase in the ilmenite grade relative to the input with about 32 wt% of the total ilmenite being recovered in the enriched output. These experiments have highlighted other underlying factors that influenced the experimental research such as the design of testbed components, system residuals and limited availability for Off-the-shelf components. The observations made from these experiments have also provided insights into the further development of the technology. The work has thus produced evidence for the effectiveness of the beneficiation testbed in producing an enriched feedstock while outlining avenues for future improvements.

Non-destructive real-time analysis of plant metabolite accumulation in radish microgreens under different LED light recipes.

The future of human space missions relies on the ability to provide adequate food resources for astronauts and also to reduce stress due to the environment (microgravity and cosmic radiation). In this context, microgreens have been proposed for the astronaut diet because of their fast-growing time and their high levels of bioactive compounds and nutrients (vitamins, antioxidants, minerals, etc.), which are even higher than mature plants, and are usually consumed as ready-to-eat vegetables. Our study aimed to identify the best light recipe for the soilless cultivation of two cultivars of radish microgreens (Raphanus sativus, green daikon, and rioja improved) harvested eight days after sowing that could be used for space farming. The effects on plant metabolism of three different light emitting diodes (LED) light recipes (L1-20% red, 20% green, 60% blue; L2-40% red, 20% green, 40% blue; L3-60% red, 20% green, 20% blue) were tested on radish microgreens hydroponically grown. A fluorimetric-based technique was used for a real-time non-destructive screening to characterize plant methabolism. The adopted sensors allowed us to quantitatively estimate the fluorescence of flavonols, anthocyanins, and chlorophyll via specific indices verified by standardized spectrophotometric methods. To assess plant growth, morphometric parameters (fresh and dry weight, cotyledon area and weight, hypocotyl length) were analyzed. We observed a statistically significant positive effect on biomass accumulation and productivity for both cultivars grown under the same light recipe (40% blue, 20% green, 40% red). We further investigated how the addition of UV and/or far-red LED lights could have a positive effect on plant metabolite accumulation (anthocyanins and flavonols). These results can help design plant-based bioregenerative life-support systems for long-duration human space exploration, by integrating fluorescence-based non-destructive techniques to monitor the accumulation of metabolites with nutraceutical properties in soilless cultivated microgreens.

Microbial products for space nutrition

Sustainably producing nutrients beyond Earth is one of the biggest technical challenges for future extended human space missions. Microorganisms such as microalgae and cyanobacteria can provide astronauts with nutrients, pharmaceuticals, pure oxygen, and bio-based polymers, making them an interesting resource for constructing a circular bioregenerative life support system in space.

Perceptual Cycles Travel Across Retinotopic Space.

Visual perception waxes and wanes periodically over time at low frequencies (theta: 4-7 Hz; alpha: 8-13 Hz), creating "perceptual cycles." These perceptual cycles can be induced when stimulating the brain with a flickering visual stimulus at the theta or alpha frequency. Here, we took advantage of the well-known organization of the visual system into retinotopic maps (topographic correspondence between visual and cortical spaces) to assess the spatial organization of induced perceptual cycles. Specifically, we tested the hypothesis that they can propagate across the retinotopic space. A disk oscillating in luminance (inducer) at 4, 6, 8, or 10 Hz was presented in the periphery of the visual field to induce perceptual cycles at specific frequencies. EEG recordings verified that the brain responded at the corresponding inducer frequencies and their first harmonics. Perceptual cycles were assessed with a concurrent detection task-target stimuli were displayed at threshold contrast (50% detection) at random times during the inducer. Behavioral results confirmed that perceptual performance was modulated periodically by the inducer at each frequency. We additionally manipulated the distance between the target and the inducer (three possible positions) and showed that the optimal phase, that is, moment of highest target detection, shifted across target distance to the inducer, specifically when its flicker frequency was in the alpha range (8 and 10 Hz). These results demonstrate that induced alpha perceptual cycles travel across the retinotopic space in humans at a propagation speed of 0.3-0.5 m/sec, consistent with the speed of unmyelinated horizontal connections in the visual cortex.

So sorry your grandma died. Get that paper in.”: Graduate Teaching Assistants' Experiences of Student Grief in the Communication Classroom

Graduate teaching assistants (GTAs) are faced with managing how to respond to student disclosures of grief in the classroom but often lack grief training from their universities when these instances occur. Good and Mad grief, and Critical Grief Pedagogy (CGP) are the frameworks for which this study is positioned. Through interviews with GTAs in the United States, we explore their experiences when engaging with student grief disclosures and revealed three main themes: regulations and boundaries, transactional exchanges in institutions, and the classroom being a human space. We also discuss how GTAs use CGP to manage these interactions. We further suggest that GTA training should include CGP to help prepare future instructors for student grief and welcome grief into the classroom.

СУЧАСНИЙ ТА ДАВНІЙ РЕЛЬЄФ ГЕОАРХЕОЛОГІЧНОЇ ПАМ'ЯТКИ МЕЖИРІЧ

Background. Comprehensive geoarchaeological studies of prehistoric and historic human settlements involve analyzing all components of the ancient natural environment, including topography and landforming processes. However, insufficient attention to documenting these crucial characteristics, as well as arbitrary use of geomorphological terms, complicates their further interpretation. The research aims to revise existing geomorphological descriptions and paleogeomorphological reconstructions of the Mezhyrich geoarchaeological site, refining and detailing its position within the modern and ancient land surface structure. Methods. The research was conducted using cartographic methods and decoding materials from aerial photography. Additionally, a thorough bibliographic analysis of scientific publications related to paleogeographical reconstructions of the study area was carried out. Results. Discrepancies have been identified in precisely determining the geomorphological context of this site. The study delves into contentious issues surrounding various approaches to numbering the floodplain terraces. These debates stem from the use of different stratigraphic schemes for Ukraine's Quaternary deposits when dating alluvium. Additionally, the debate extends to criteria for terrace numbering. Through the analysis of satellite imagery, hypsometric and geomorphological diagrams, and other geological-geomorphological materials, the contemporary geomorphological situation has been refined, and the peculiarities of the ancient terrain have been unearthed. The role of morphostructural position, the spectrum of processes, and the dynamics of morpholithogenesis have been pinpointed. Conclusions. The conducted research substantiates the pivotal role of terrain in the selection and organization of safe living spaces for ancient humans. To address the issue of linking the Mezhyrich geoarchaeological site to the terrace level, the proposal is to number the terraces based on morphological features, thereby avoiding divergent interpretations of the ages of correlated deposits and discrepancies in terrace designations. Furthermore, there is potential for utilizing the geomorphological information from the investigated Late Paleolithic settlement as a search criterion for locating other ancient human settlements under similar physiogeographic and geological-structural conditions.

Lo posthumano en la era del Antropoceno. Transhumanismo, hibridación y agencia no-humana en la trilogía Arrebato, de Enki Bilal

In Enki Bilal’s graphic novel trilogy Coup de sang (2009-2015), the Francophone author depicts the Earth’s decision, after centuries of suffering anthropogenic environmental damage, to transform into a hostile space for humans. This phenomenon, as will be demonstrated, is related to contemporary discourses surrounding non-human agency in the Anthropocene era. In the post-apocalyptic environment in which Animal’z (2009), Julia & Roem (2011), and La Couleur de l’air (2014) take place, characteristic of the imagination of the Anthropocene and the climate fiction genre, the few survivors have adopted a hybrid human-animal mode of existence in their desperate attempt to survive. This raises issues of current relevance within the framework of post-humanist and post-anthropocentric philosophical currents by blurring the existing boundaries between the human and the non-human, while also referring to the possibilities and dangers of transhumanist technology.

Pediatric Respiratory Pathogens Circulate in Children and Adults in Communities Near Susceptible Wild Great Ape Populations in Uganda

Respiratory infections are a leading cause of death in developing countries. Infants and young children are especially susceptible to disease because they lack immunity, whereas adults who have acquired immunity can be infected asymptomatically. Great ape species, all of which are endangered, are similarly susceptible to respiratory illnesses caused by human respiratory pathogens. We obtained 432 nasopharyngeal swab samples (127 from adults and 305 from children) in a cross‐sectional study that took place between February and October 2022 at four sites in Western Uganda (Budongo Central Forest Reserve, Bulindi Town Council, Bwindi Impenetrable National Park, and Kibale National Park) where the participants live in communities where interaction with apes is frequent. Prior research at Kibale has shown that locally circulating human respiratory pathogens have led to multiple lethal outbreaks in wild eastern chimpanzees (Pan troglodytes schweinfurthii). We used a multiplex PCR panel to characterize respiratory pathogens, with the goal of assessing whether respiratory illnesses in the chimpanzees of Budongo and Bulindi and the mountain gorillas (Gorilla beringei beringei) of Bwindi might have originated in local children and been introduced to the apes via asymptomatic adult carriers. The prevalence of respiratory pathogens was twice as high in Bwindi (44.0%) as it was in Budongo (24.0%) and Bulindi (20.8%), while the prevalence was intermediate at Kibale (34.4%). Rates of respiratory pathogen detection were higher but statistically indistinguishable in children compared to adults at Budongo and Bulindi, and children were 15.0 times more likely than adults to have positive detections at Kibale. At Bwindi, however, the pattern was reversed, with adults 2.6 times more likely than children to have positive detections. Rhinovirus, metapneumovirus, human parainfluenza virus 3, respiratory syncytial virus, and coronavirus OC43, all of which have been identified as causative agents of respiratory disease outbreaks in great ape populations across sub‐Saharan Africa, accounted for three quarters (73.6%) of detected pathogens. Our data support the idea that human respiratory pathogens that can infect great apes occur at high frequencies in human populations in Western Uganda that live close to and interact with wild apes that have suffered from lethal outbreaks caused by these same pathogens. Reducing respiratory infections in local children, thereby reducing both carriage of those infections into the forest by people and ape exposure to these pathogens when they enter human spaces, should decrease the risk of respiratory disease outbreaks in apes.

“Multispacecraft to Multidebris” Space Debris Removal Strategy Based on Target Allocation Method

The combination of increased amount of “space junk”, lack of precise tracking information and control of items orbiting Earth, and debris from past collisions posed important threats to human space missions. In this study, a strategy enabling “multispacecraft to multidebris” debris removal task is proposed. By analyzing the current distribution of space debris, 282 large debris and rocket bodies are selected as target database. The traditional-density-based spatial clustering of applications with noise algorithm is innovatively modified by defining the speed increment as threshold parameter for dividing target debris into different clusters. Then, the Hungarian-algorithm-based target allocation strategy is used to assign multispacecraft to different debris clusters for the removal mission. Simulations verify the effectiveness of the proposed “multispacecraft to multidebris” strategy that is able to remove as much as 83.33% of the total 282 target debris.