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1.
Materials (Basel) ; 17(17)2024 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-39274631

RESUMEN

For space missions to either the Moon or Mars, protecting mechanical moving parts from the abrasive effects of prevailing surface dust is crucial. This paper compares the abrasive effects of two lunar and two Martian simulant regoliths using special pin-on-disc tests on a stainless steel/polytetrafluoroethylene (PTFE) sealing material pair. Due to the regolith particles entering the contact zone, a three-body abrasion mechanism took place. We found that friction coefficients stabilised between 0.2 and 0.4 for all simulants. Wear curves, surface roughness measurements, and microscopic images all suggest a significantly lower abrasion effect of the Martian regoliths than that of the lunar ones. It applies not only to steel surfaces but also to the PTFE pins. The dominant abrasive micro-mechanism of the disc surface is micro-ploughing in the case of all tests, while the transformation of the counterface is mixed. The surface of pin material is plastically transformed through micro-ploughing, while the material is removed through micro-cutting due to the slide over hard soil particles.

2.
Biol Futur ; 2024 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-39302628

RESUMEN

In recent years, the realm of astrobiology has expanded beyond the search for microbial life to encompass the intriguing possibility of plant life beyond our planet. Plant astrobiology delves into the adaptations and mechanisms that might allow Earth's flora to flourish in the harsh conditions of outer space and other celestial bodies. This review aims to shed light on the captivating field of plant astrobiology, its implications, and the challenges and opportunities it presents. Plant astrobiology marries the disciplines of botany and astrobiology, challenging us to envision the growth of plants beyond Earth's atmosphere. Researchers in this field are not only exploring the potential for plant life on other planets and moons but also investigating how plants could be harnessed to sustain life during extended space missions. The review discusses how plants could adapt to environments characterized by low gravity, high radiation, extreme temperature fluctuations, and different atmospheric compositions. It highlights the physiological changes necessary for plants to survive and reproduce in these conditions. A pivotal concept is the integration of plants into closed-loop life support systems, where plants would play a crucial role in recycling waste products, generating oxygen, and producing food. The review delves into ongoing research involving genetic modifications and synthetic biology techniques to enhance plants' resilience in space environments. It addresses ethical considerations associated with altering organisms for off-planet habitation. Additionally, the review contemplates the psychological and emotional benefits of having greenery in enclosed, isolated space habitats. The review concludes that by employing advanced research methodologies, the field of plant astrobiology can greatly enhance the viability and sustainability of future space missions, highlighting the essential role of plants in sustaining long-term human presence beyond Earth.

3.
Biomimetics (Basel) ; 9(8)2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-39194475

RESUMEN

Bio-inspired strategies for robotic sensing are essential for in situ manufactured sensors on the Moon. Sensors are one crucial component of robots that should be manufactured from lunar resources to industrialize the Moon at low cost. We are concerned with two classes of sensor: (a) position sensors and derivatives thereof are the most elementary of measurements; and (b) light sensing arrays provide for distance measurement within the visible waveband. Terrestrial approaches to sensor design cannot be accommodated within the severe limitations imposed by the material resources and expected manufacturing competences on the Moon. Displacement and strain sensors may be constructed as potentiometers with aluminium extracted from anorthite. Anorthite is also a source of silica from which quartz may be manufactured. Thus, piezoelectric sensors may be constructed. Silicone plastic (siloxane) is an elastomer that may be derived from lunar volatiles. This offers the prospect for tactile sensing arrays. All components of photomultiplier tubes may be constructed from lunar resources. However, the spatial resolution of photomultiplier tubes is limited so only modest array sizes can be constructed. This requires us to exploit biomimetic strategies: (i) optical flow provides the visual navigation competences of insects implemented through modest circuitry, and (ii) foveated vision trades the visual resolution deficiencies with higher resolution of pan-tilt motors enabled by micro-stepping. Thus, basic sensors may be manufactured from lunar resources. They are elementary components of robotic machines that are crucial for constructing a sustainable lunar infrastructure. Constraints imposed by the Moon may be compensated for using biomimetic strategies which are adaptable to non-Earth environments.

4.
Sensors (Basel) ; 24(16)2024 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-39205055

RESUMEN

This article explores the influence of lunar regolith and rover structure, such as mast design and material composition, on antenna parameters. It focuses on the distinctive difficulties of communication in the lunar environment, which need specialized antenna solutions. This study specifically examines the performance of antennas on the lunar Rashid rover within the Atlas crater, a landing site on the moon, considering two antenna types: a sleeve dipole antenna and an all-metal patch antenna. Thermal analyses reveal temperatures in the Atlas crater can exceed 80 °C during lunar mid-day. The findings highlight the effect of different materials used as thermal coatings for Rashid rover antennas, as well as the influence of rover materials on antenna performance. Furthermore, this study extends to analyze the conductivity and depth of lunar regolith within the Atlas crater. Given the critical role of antennas in wireless communication, understanding how lunar regolith properties affect antenna performance is essential. This research contributes to the creation of a strong communication system for the Rashid rover and future lunar missions by considering the features of the lunar regolith in addition to the rover's size and material attributes.

5.
Proc Biol Sci ; 291(2028): 20240613, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39106960

RESUMEN

Lunar rhythms shape spawning phenology and subsequent risks and rewards for early life-history stages in the sea. Here, we consider a perplexing spawning phenology of the sixbar wrasse (Thalassoma hardwicke), in which parents spawn disproportionately around the new moon, despite the low survival of these larvae. Because primary sex determination in this system is highly plastic and sensitive to social environments experienced early in development, we ask whether this puzzling pattern of spawning is explained by fitness trade-offs associated with primary sexual maturation. We used otoliths from 871 fish to explore how spawning on different phases of the moon shapes the environments and phenotypes of settling larvae. Offspring that were born at the new moon were more likely to settle (i) before other larvae, (ii) at a larger body size, (iii) at an older age, (iv) to the best quality sites, and (v) as part of a social group-all increasing the likelihood of primary maturation to male. Selection of birthdates across life stage transitions suggests that the perplexing spawning phenology of adults may reflect an evolutionarily stable strategy that includes new moon spawning for compensatory benefits later in life, including preferential production of primary males at certain times.


Asunto(s)
Arrecifes de Coral , Luna , Perciformes , Animales , Perciformes/fisiología , Masculino , Femenino , Procesos de Determinación del Sexo , Reproducción , Maduración Sexual , Larva/fisiología , Larva/crecimiento & desarrollo
6.
Space Sci Rev ; 220(6): 62, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39176178

RESUMEN

As a first step in preparing for the return of samples from the Moon by the Artemis Program, NASA initiated the Apollo Next Generation Sample Analysis Program (ANGSA). ANGSA was designed to function as a low-cost sample return mission and involved the curation and analysis of samples previously returned by the Apollo 17 mission that remained unopened or stored under unique conditions for 50 years. These samples include the lower portion of a double drive tube previously sealed on the lunar surface, the upper portion of that drive tube that had remained unopened, and a variety of Apollo 17 samples that had remained stored at -27 °C for approximately 50 years. ANGSA constitutes the first preliminary examination phase of a lunar "sample return mission" in over 50 years. It also mimics that same phase of an Artemis surface exploration mission, its design included placing samples within the context of local and regional geology through new orbital observations collected since Apollo and additional new "boots-on-the-ground" observations, data synthesis, and interpretations provided by Apollo 17 astronaut Harrison Schmitt. ANGSA used new curation techniques to prepare, document, and allocate these new lunar samples, developed new tools to open and extract gases from their containers, and applied new analytical instrumentation previously unavailable during the Apollo Program to reveal new information about these samples. Most of the 90 scientists, engineers, and curators involved in this mission were not alive during the Apollo Program, and it had been 30 years since the last Apollo core sample was processed in the Apollo curation facility at NASA JSC. There are many firsts associated with ANGSA that have direct relevance to Artemis. ANGSA is the first to open a core sample previously sealed on the surface of the Moon, the first to extract and analyze lunar gases collected in situ, the first to examine a core that penetrated a lunar landslide deposit, and the first to process pristine Apollo samples in a glovebox at -20 °C. All the ANGSA activities have helped to prepare the Artemis generation for what is to come. The timing of this program, the composition of the team, and the preservation of unopened Apollo samples facilitated this generational handoff from Apollo to Artemis that sets up Artemis and the lunar sample science community for additional successes.

7.
Theor Popul Biol ; 160: 1-13, 2024 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-39182695

RESUMEN

Settlement is a critical transition in the life history of reef fish, and the timing of this event can have a strong effect on fitness. Key factors that influence settlement timing are predictable lunar cyclic variation in tidal currents, moonlight, and nocturnal predation risk as larvae transition from pelagic to benthic environments. However, populations typically display wide variation in the arrival of settlers over the lunar cycle. This variation is often hypothesized to result from unpredictable conditions in the pelagic environment and bet-hedging by spawning adults. Here, we consider the hypothesis that the timing of spawning and settlement is a strategic response to post-settlement competition. We use a game theoretic model to predict spawning and settlement distributions when fish face a tradeoff between minimizing density-independent predation risk while crossing the reef crest vs. avoiding high competitor density on settlement habitat. In general, we expect competition to spread spawning over time such that settlement is distributed around the lunar phase with the lowest predation risk, similar to an ideal free distribution in which competition spreads competitors across space. We examine the effects of overcompensating density dependence, age-dependent competition, and competition among daily settler cohorts. Our model predicts that even in the absence of stochastic variation in the larval environment, competition can result in qualitative divergence between spawning and settlement distributions. Furthermore, we show that if competitive strength increases with settler age, competition results in covariation between settler age and settlement date, with older larvae settling when predation risk is minimal. We predict that competition between daily cohorts delays peak settlement, with priority effects potentially selecting for a multimodal settlement distribution.

8.
Front Physiol ; 15: 1417719, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38989048

RESUMEN

Introduction: Space is a unique environment characterized by isolation from community life and exposure to circadian misalignment, microgravity, and space radiation. These multiple differences from those experienced on the earth may cause systemic and local tissue stress. Autonomic nerves, including sympathetic and parasympathetic nerves, regulate functions in multiple organs. Saliva is secreted from the salivary gland, which is regulated by autonomic nerves, and plays several important roles in the oral cavity and digestive processes. The balance of the autonomic nervous system in the seromucous glands, such as the submandibular glands, precisely controls serous and mucous saliva. Psychological stress, radiation damage, and other triggers can cause an imbalance in salivary secretion systems. A previous study reported that amylase is a stress marker in behavioral medicine and space flight crews; however, the detailed mechanisms underlying amylase regulation in the space environment are still unknown. Methods: In this study, we aimed to elucidate how lunar gravity (1/6 g) changes mRNA expression patterns in the salivary gland. Using a multiple artificial gravity research system during space flight in the International Space Station, we studied the effects of two different gravitational levels, lunar and Earth gravity, on the submandibular glands of mice. All mice survived, returned to Earth from space, and their submandibular glands were collected 2 days after landing. Results: We found that lunar gravity induced the expression of the salivary amylase gene Amy1; however, no increase in Aqp5 and Ano1, which regulate water secretion, was observed. In addition, genes involved in the exocrine system, such as vesicle-associated membrane protein 8 (Vamp8) and small G proteins, including Rap1 and Rab families, were upregulated under lunar gravity. Conclusion: These results imply that lunar gravity upregulates salivary amylase secretion via Rap/Rab signaling and exocytosis via Vamp8. Our study highlights Amy1 as a potential candidate marker for stress regulation in salivary glands in the lunar gravity environment.

9.
Sci Total Environ ; 948: 174603, 2024 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-39002579

RESUMEN

The investigation of lunar soil encompasses extensive periods, employs many improvement methods, and has generated several simulants. The improvement of lunar soil has recently garnered growing interest as an aspect of In-Situ Resource Utilization (ISRU) for regolith. It is crucial to clarify the challenges of utilizing lunar soil as a planting substrate to develop more effective techniques. This review presents a comprehensive analysis of research on improving lunar soil properties, highlights the disparities in mineral composition between real lunar soil (also called regolith) and simulated lunar soil, then details their deficiencies as planting substrates. Following an investigation of existing improvement methods, a dilemma of metals、salt precipitation and high pH caused by adding organic matter alone was noted, while the function of microbes (bacteria, algae, and lichens) in improvement processes was assessed. Finally, we present a perspective on future the lunar soil plantable research development based on the Bioregenerative Life Support System (BLSS). This review aims to promote the engineering application of lunar soil improvements and sustainable development. We hope that one day, regolith will enable plants to flourish on the Moon.


Asunto(s)
Luna , Suelo , Suelo/química
10.
Proc Natl Acad Sci U S A ; 121(30): e2406930121, 2024 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-39008671

RESUMEN

The melting of ice sheets and global glaciers results in sea-level rise, a pole-to-equator mass transport increasing Earth's oblateness and resulting in an increase in the length of day (LOD). Here, we use observations and reconstructions of mass variations at the Earth's surface since 1900 to show that the climate-induced LOD trend hovered between 0.3 and 1.0 ms/cy in the 20th century, but has accelerated to 1.33 [Formula: see text] 0.03 ms/cy since 2000. We further show that surface mass transport fully explains the accelerating trend in the Earth oblateness observed in the past three decades. We derive an independent measure of the decreasing LOD trend induced by Glacial Isostatic Adjustment (GIA) of [Formula: see text]0.80 [Formula: see text] 0.10 ms/cy, which provides a constraint for the mantle viscosity. The sum of this GIA rate and lunar tidal friction fully explains the secular LOD trend that is inferred from the eclipse record in the past three millennia prior to the onset of contemporary climate change. Projections of future climate warming under high emission scenarios suggest that the climate-induced LOD rate may reach 2.62 [Formula: see text] 0.79 ms/cy by 2100, overtaking lunar tidal friction as the single most important contributor to the long-term LOD variations.

11.
Discov Immunol ; 3(1): kyae007, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38863794

RESUMEN

Immune responses are widely accepted to be under circadian regulation via a molecular clock, with many practical consequences, but much less is known of how other biological rhythms could affect the immune system. In this study, we search for lunar rhythms (circalunar, circasemilunar, and circatidal cycles) in the immune expression of the recently marine-derived freshwater fish, the low-plate morph of the three-spined stickleback. We employed time series of immune expression (mRNA) measurements for 14 immune-associated genes, representing a variety of immunological pathways. Times series measurements were taken on fish populations in the wild, in seminatural outdoor mesocosms, and in the laboratory, according to sampling regimens originally designed to study circannual variation but with the additional potential to provide information about lunar variation. Our evidence best supported the existence of a very small endogenous tidal rhythm. This is consistent with previous suggestions of the existence of a primordial tidal endogenous clock, some elements of which may be conserved in animals evolving outside the marine environment.

12.
Ann Biomed Eng ; 52(9): 2534-2545, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38836980

RESUMEN

Extravehicular activities will play a crucial role in lunar exploration on upcoming Artemis missions and may involve astronauts operating a lunar terrain vehicle (LTV) in a standing posture. This study assessed kinematic response and injury risks using an active muscle human body model (HBM) restrained in an upright posture on the LTV by simulating dynamic acceleration pulses related to lunar surface irregularities. Linear accelerations and rotational displacements of 5 lunar obstacles (3 craters; 2 rocks) over 5 slope inclinations were applied across 25 simulations. All body injury metrics were below NASA's injury tolerance limits, but compressive forces were highest in the lumbar (250-550N lumbar, tolerance: 5300N) and lower extremity (190-700N tibia, tolerance: 1350N) regions. There was a strong association between the magnitudes of body injury metrics and LTV resultant linear acceleration (ρ = 0.70-0.81). There was substantial upper body motion, with maximum forward excursion reaching 375 mm for the head and 260 mm for the chest. Our findings suggest driving a lunar rover in an upright posture for these scenarios is a low severity impact presenting low body injury risks. Injury metrics increased along the load path, from the lower body (highest metrics) to the upper body (lowest metrics). While upper body injury metrics were low, increased body motion could potentially pose a risk of injury from flail and occupant interaction with the surrounding vehicle, suit, and restraint hardware.


Asunto(s)
Luna , Humanos , Proyectos Piloto , Actividad Extravehicular , Aceleración , Fenómenos Biomecánicos , Modelos Biológicos , Heridas y Lesiones/fisiopatología , Masculino
13.
Chronobiol Int ; 41(7): 929-940, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38888285

RESUMEN

The growth of Sphagnum is influenced by the lunar cycle, which suggests a corresponding carbon (C) accumulation rhythm in peatlands. However, this rhythm can only occur if C accumulation from Sphagnum growth is not offset by its total losses through respiration and other processes. To address the uncertainty, through correlation-regression analysis we examine the influence of the lunar cycle on recent measurements of ecosystem (ER) and heterotrophic (Rh) respiration conducted by Järveoja and colleagues on the oligotrophic peatland of Degerö Stormyr. We found that ER and Rh accelerated near the full moon and slowed down near the new moon. The response of the hourly ER to the lunar cycle is significant from 22:00 to 8:00 and is not significant beyond this range. This response was concentrated in the initial and finished phases of the season, but during the middle of the season it disappeared. This behavior could potentially be caused by the high sensitivity of the Sphagnum cover to moonlight, as well as the sensitivity to the lunar cycle of only the nocturnal component ER. During most of the day, the lunar cycle had a significant effect on hourly Rh, with the highest impact observed between 5:00 and 10:00 and at 20:00. The greatest impact occurs during those hours when ER declines, and possibly Sphagnum photosynthetic productivity peaks. The findings suggest a circalunar rhythm of C accumulation in peatlands due to the opposite trends between C accumulation during Sphagnum growth and C losses with respiration during the lunar cycle.


Asunto(s)
Ritmo Circadiano , Ecosistema , Luna , Sphagnopsida , Sphagnopsida/metabolismo , Ritmo Circadiano/fisiología , Estaciones del Año , Procesos Heterotróficos/fisiología , Suelo/química , Carbono/metabolismo
14.
Polymers (Basel) ; 16(11)2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38891528

RESUMEN

The construction of lunar bases represents a fundamental challenge for deep space exploration, lunar research, and the exploitation of lunar resources. In-situ resource utilization (ISRU) technology constitutes a pivotal tool for constructing lunar bases. Using lunar regolith to create geopolymers as construction materials offers multiple advantages as an ISRU technique. This paper discusses the principle of geopolymer for lunar regolith, focusing on the reaction principle of geopolymer. It also analyzes the applicability of geopolymer under the effects of the lunar surface environment and the differences between the highland and mare lunar regolith. This paper summarizes the characteristics of existing lunar regolith simulants and the research on the mechanical properties of lunar regolith geopolymers using lunar regolith simulants. Highland lunar regolith samples contain approximately 36% amorphous substances, the content of silicon is approximately 28%, and the ratios of Si/Al and Si/Ca are approximately 1.5 and 2.6, respectively. They are more suitable as precursor materials for geopolymers than mare samples. The compressive strength of lunar regolith geopolymer is mainly in the range of 18~30 MPa. Sodium silicate is the most commonly utilized activator for lunar regolith geopolymers; alkalinity in the range of 7% to 10% and modulus in the range of 0.8 to 2.0 are suitable. A vacuum environment and multiple temperature cycles reduce the mechanical properties of geopolymers by 8% to 70%. Future research should be concentrated on the precision control of the lunar regolith's chemical properties and the alkali activation efficacy of geopolymers in the lunar environment.

15.
Materials (Basel) ; 17(9)2024 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-38730852

RESUMEN

Lunar mare basalt is recognized as an important in situ resource on the lunar surface. However, the significant compositional variability of lunar mare basalts introduces uncertainties concerning the potential for their use in fabricating fibers and composite materials. This study investigates the impact of different components on the fiber-forming capabilities of mare basalts by simulating the compositions of basalts collected from several well-known lunar missions and then preparing simulated lunar mare basalt fibers. Raman spectroscopy is primarily employed for analysis and characterization, using "peak area normalization" to explore the impact of compositional fluctuations in the simulated lunar mare basalts on the glass network structure. The findings indicate that an increase in the Fe content raises the likelihood of basalt fibers crystallizing. Additionally, Fe3+ is shown to substitute for Si and Al in constructing bridging oxygen bonds in the network structure, albeit reducing the overall polymerization of the network. Meanwhile, Fe2+ acts as a network modifier to enhance the mechanical properties of the fibers.

16.
J Educ Health Promot ; 13: 111, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38726075

RESUMEN

BACKGROUND: Children with Down syndrome (DS) offer a compelling context within the fieldof human biology for examining potential lunar influences. While the exact mechanisms governing lunar effects are still under investigation, a growing body of scientific inquiry suggests possible connections between lunar phases and physiological, physical, and cognitive parameters. This investigation holds promise for uncovering the intricate interplay between lunar cycles (LCs) and the unique biology of children with DS. This study investigated the potential influence of the LC on physiological, physical, and cognitive parameters in children with DS, focusing on sleep patterns, physical performance, and cognitive abilities. MATERIALS AND METHODS: Seventeen children with DS participated in this study. Sleep data, physical performance metrics, and cognitive test results were collected throughout the LC, including the new moon (NM), first quarter, full moon (FM), and third quarter. Statistical analyses were conducted to assess the differences in these parameters across lunar phases. RESULTS: Significant differences were observed in sleep patterns, with reduced total sleep time (P < 0.01) and sleep efficiency (P < 0.001) during the FM phase. Heart rates (HRs) before (P < 0.001) and after (P < 0.01) exercise also displayed pronounced changes during LC. Additionally, the reaction time (RT) exhibited a significant difference (P < 0.01) across the lunar phases. However, physical performance metrics, including squat jump (SJ), sprint, and 6-minute walk distance (6MWD), did not show significant variations. CONCLUSION: This study suggests that LC may have a moderating effect on sleep patterns, HR, and cognitive performance in children with DS. These findings have practical implications for caregivers and educators and highlight the importance of considering lunar-associated variations in planning schedules and interventions for children with DS.

17.
Uisahak ; 33(1): 1-57, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38768990

RESUMEN

Borneol(yongnoe) was a fragrance and medicinal ingredient with unique efficacy. However, it could be produced only in tropical Southeast Asia and obtained only through international trade. In addition, camphor(jangnoe) with similar material properties was developed and distributed as an inexpensive replacement for borneol, although the processing method is different from that of borneol. Even in Joseon Korea, borneol and camphor were recognized as separate medicines, and efforts were made to obtain a high-quality borneol. Borneol and camphor have a unique effect of relieving inflammation, pain and heavy feeling, so it could be widely applied to symptoms in various diseases. During the Joseon period, borneol was a rare item that could only be obtained through foreign trade, and it was also used for perfumes and insect repellents, but most widely used as medicine. There are many records of actually prescribing borneol to the royal family, and many medicines containing borneol and its effective symptoms were also recorded in the medical books. Borneol was able to spread widely in Joseon society thanks to the practice of distributing 'nabyak' to court officials every year in the twelfth month of the lunar calendar. Since nabyak was used as a household medicine that was stored and used when necessary, pills containing borneol that could be applied to various symptoms were suitable for this purpose. Despite considerable medical demand, borneol was one of the important 'dangyakjae', the Chinese medicines imported to Joseon. During the Joseon period, borneol was imported through China and Japan, but genuine borneol was difficult to obtain, so it was often presented to Joseon as gifts of envoy trade. It is thought that camphor was also imported, but it is not well mentioned in official records or medical books reflecting national demand. Perhaps this is thought to be because the government prioritized securing better quality borneol rather than campher. In the early 17th century, due to the instability of the envoy's route to the Ming Dynasty, Joseon had to import borneol only through the sea. As a result, there were problems with the supply and quality of borneol, and national interest in Japanese borneol temporarily increased. However, as the relationship with the Qing Dynasty stabilized, a system was established to import national borneol demand through the annual envoy trade. Naeuiwon, the medical center for the royal family is in charge of securing and prescribing Chinese medicines, but the cost was covered by the silver paid by Hojo, the ministry of finance of Joseon Dynasty. Since the amount of Chinese medicines used in the preparation of nabyak was not small, the financial burden of importing enough medicines including borneol increased. The purveyors for government played a role in supplying Chinese medicines to the government. Their appearance shows that private merchants were actively involved in the trade of Chinese medicines including borneol. The formation of the medicinal market by private merchants' activities greatly contributed to the widespread expansion of the applications and distribution of borneol.


Asunto(s)
Canfanos , Canfanos/historia , Humanos , Alcanfor/historia , Repelentes de Insectos/historia
18.
Front Vet Sci ; 11: 1394004, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38818498

RESUMEN

Introduction: Various climatological and lunar cycle parameters have a direct impact on animal reproduction, and in the case of the avian species, spermatozoa are extremely sensitive to heat stress. These parameters could influence sperm freezability, which will ultimately affect post-thawing semen quality, being sperm motility in roosters a relevant indicator of this quality as it is highly related to fertility. Therefore, the objective of the present study is to determine which are the climatological and lunar cycle parameters that have a greater effect on sperm freezability in roosters. Methods: Sperm was obtained from 16 Utrerana breed roosters and a total of 27 replicates were performed. A pool was made with those ejaculates that met the minimum quality criteria for each replicate, and four freezing-thawing samples per replicate were analyzed. The straws were thawed, and sperm motility was evaluated, classifying the results obtained into four seminal quality groups according to the guidelines of the Food and Agriculture Organization of the United Nations (Group 1: Good, Group 2: Satisfactory, Group 3: Acceptable but undesirable and Group 4: Unsatisfactory). The following traits were recorded for each day of semen collection: maximum temperature, minimum temperature, maximum barometric pressure, minimum barometric pressure, maximum gust, wind direction, mean wind speed, sunshine hours, rainfall, moon phase, and percentage of illuminated lunar surface over the total area. Results: A discriminant canonical analysis was performed to determine which of these parameters offered the most information when classifying an ejaculate in each quality group, with minimum temperature, the new moon as moon phase, minimum barometric pressure, and rainfall being the most significant variables. Discussion: According to the results obtained, semen quality decreases when temperature and precipitation are lower, pressure is higher, and when there is a new moon phase. Therefore, these environmental conditions should be avoided for sperm collection and processing.

19.
Space Sci Rev ; 220(4): 37, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38756703

RESUMEN

The Lunar Environment heliospheric X-ray Imager (LEXI) is a wide field-of-view soft X-ray telescope developed to study solar wind-magnetosphere coupling. LEXI is part of the Blue Ghost 1 mission comprised of 10 payloads to be deployed on the lunar surface. LEXI monitors the dayside magnetopause position and shape as a function of time by observing soft X-rays (0.1-2 keV) emitted from solar wind charge-exchange between exospheric neutrals and high charge-state solar wind plasma in the dayside magnetosheath. Measurements of the shape and position of the magnetopause are used to test temporal models of meso- and macro-scale magnetic reconnection. To image the boundary, LEXI employs lobster-eye optics to focus X-rays to a microchannel plate detector with a 9.1×∘9.1∘ field of view.

20.
Sci Bull (Beijing) ; 69(13): 2136-2148, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-38777682

RESUMEN

Lunar exploration is deemed crucial for uncovering the origins of the Earth-Moon system and is the first step for advancing humanity's exploration of deep space. Over the past decade, the Chinese Lunar Exploration Program (CLEP), also known as the Chang'e (CE) Project, has achieved remarkable milestones. It has successfully developed and demonstrated the engineering capability required to reach and return from the lunar surface. Notably, the CE Project has made historic firsts with the landing and on-site exploration of the far side of the Moon, along with the collection of the youngest volcanic samples from the Procellarum KREEP Terrane. These achievements have significantly enhanced our understanding of lunar evolution. Building on this success, China has proposed an ambitious crewed lunar exploration strategy, aiming to return to the Moon for scientific exploration and utilization. This plan encompasses two primary phases: the first crewed lunar landing and exploration, followed by a thousand-kilometer scale scientific expedition to construct a geological cross-section across the lunar surface. Recognizing the limitations of current lunar exploration efforts and China's engineering and technical capabilities, this paper explores the benefits of crewed lunar exploration while leveraging synergies with robotic exploration. The study refines fundamental lunar scientific questions that could lead to significant breakthroughs, considering the respective engineering and technological requirements. This research lays a crucial foundation for defining the objectives of future lunar exploration, emphasizing the importance of crewed missions and offering insights into potential advancements in lunar science.

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