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1.
Brain ; 147(6): 2085-2097, 2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38735647

RESUMEN

Biallelic pathogenic variants in the PNPLA6 gene cause a broad spectrum of disorders leading to gait disturbance, visual impairment, anterior hypopituitarism and hair anomalies. PNPLA6 encodes neuropathy target esterase (NTE), yet the role of NTE dysfunction on affected tissues in the large spectrum of associated disease remains unclear. We present a systematic evidence-based review of a novel cohort of 23 new patients along with 95 reported individuals with PNPLA6 variants that implicate missense variants as a driver of disease pathogenesis. Measuring esterase activity of 46 disease-associated and 20 common variants observed across PNPLA6-associated clinical diagnoses unambiguously reclassified 36 variants as pathogenic and 10 variants as likely pathogenic, establishing a robust functional assay for classifying PNPLA6 variants of unknown significance. Estimating the overall NTE activity of affected individuals revealed a striking inverse relationship between NTE activity and the presence of retinopathy and endocrinopathy. This phenomenon was recaptured in vivo in an allelic mouse series, where a similar NTE threshold for retinopathy exists. Thus, PNPLA6 disorders, previously considered allelic, are a continuous spectrum of pleiotropic phenotypes defined by an NTE genotype:activity:phenotype relationship. This relationship, and the generation of a preclinical animal model, pave the way for therapeutic trials, using NTE as a biomarker.


Asunto(s)
Fenotipo , Animales , Femenino , Humanos , Masculino , Ratones , Aciltransferasas , Hidrolasas de Éster Carboxílico/genética , Mutación Missense , Fosfolipasas/genética , Enfermedades de la Retina/genética
2.
Proc Natl Acad Sci U S A ; 119(8)2022 02 22.
Artículo en Inglés | MEDLINE | ID: mdl-35165180

RESUMEN

The origin of volatile species such as water in the Earth-Moon system is a subject of intense debate but is obfuscated by the potential for volatile loss during the Giant Impact that resulted in the formation of these bodies. One way to address these topics and place constraints on the temporal evolution of volatile components in planetary bodies is by using the observed decay of 87Rb to 87Sr because Rb is a moderately volatile element, whereas Sr is much more refractory. Here, we show that lunar highland rocks that crystallized ∼4.35 billion years ago exhibit very limited ingrowth of 87Sr, indicating that prior to the Moon-forming impact, the impactor commonly referred to as "Theia" and the proto-Earth both must have already been strongly depleted in volatile elements relative to primitive meteorites. These results imply that 1) the volatile element depletion of the Moon did not arise from the Giant Impact, 2) volatile element distributions on the Moon and Earth were principally inherited from their precursors, 3) both Theia and the proto-Earth probably formed in the inner solar system, and 4) the Giant Impact occurred relatively late in solar system history.

3.
Proc Natl Acad Sci U S A ; 119(44): e2120682119, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36279439

RESUMEN

The most widely accepted scenario for the formation of the Earth-Moon system involves a dramatic impact between the proto-Earth and some other cosmic body. Many features of the present-day Earth-Moon system provide constraints on the nature of this impact. Any model of the history of the Earth must account for the physical, geochemical, petrological, and dynamical evidence. These constraints notwithstanding, there are several radically different impact models that could in principle account for all the evidence. Thus, in the absence of further constraints, we may never know for sure how the Earth-Moon system was formed. Here, we put forward the idea that additional constraints are indeed provided by the fact that the Earth is strongly magnetized. It is universally accepted that the Earth's magnetic field is maintained by a dynamo operating in the outer liquid core. However, because of the rapid rotation of the Earth, this dynamo has the peculiar property that it can maintain a strong field but cannot amplify a weak one. Therefore, the Earth must have been magnetized at a very early epoch, either preimpact or as a result of the impact itself. Either way, any realistic model of the formation of the Earth-Moon system must include magnetic field evolution. This requirement may ultimately constrain the models sufficiently to discriminate between the various candidates.


Asunto(s)
Planeta Tierra , Luna , Campos Magnéticos
4.
Proc Natl Acad Sci U S A ; 119(22): e2115725119, 2022 05 31.
Artículo en Inglés | MEDLINE | ID: mdl-35622889

RESUMEN

Many species synchronize their physiology and behavior to specific hours. It is commonly assumed that sunlight acts as the main entrainment signal for ∼24-h clocks. However, the moon provides similarly regular time information. Consistently, a growing number of studies have reported correlations between diel behavior and lunidian cycles. Yet, mechanistic insight into the possible influences of the moon on ∼24-h timers remains scarce. We have explored the marine bristleworm Platynereis dumerilii to investigate the role of moonlight in the timing of daily behavior. We uncover that moonlight, besides its role in monthly timing, also schedules the exact hour of nocturnal swarming onset to the nights' darkest times. Our work reveals that extended moonlight impacts on a plastic clock that exhibits <24 h (moonlit) or >24 h (no moon) periodicity. Abundance, light sensitivity, and genetic requirement indicate that the Platynereis light receptor molecule r-Opsin1 serves as a receptor that senses moonrise, whereas the cryptochrome protein L-Cry is required to discriminate the proper valence of nocturnal light as either moonlight or sunlight. Comparative experiments in Drosophila suggest that cryptochrome's principle requirement for light valence interpretation is conserved. Its exact biochemical properties differ, however, between species with dissimilar timing ecology. Our work advances the molecular understanding of lunar impact on fundamental rhythmic processes, including those of marine mass spawners endangered by anthropogenic change.


Asunto(s)
Relojes Circadianos , Ritmo Circadiano , Luna , Poliquetos , Animales , Criptocromos/genética , Criptocromos/metabolismo , Drosophila melanogaster/genética , Drosophila melanogaster/fisiología , Poliquetos/genética , Poliquetos/fisiología , Opsinas de Bastones/genética , Luz Solar
5.
Proc Natl Acad Sci U S A ; 119(40): e2117146119, 2022 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-36161904

RESUMEN

The long-term history of the Earth-Moon system as reconstructed from the geological record remains unclear when based on fossil growth bands and tidal laminations. A possibly more robust method is provided by the sedimentary record of Milankovitch cycles (climatic precession, obliquity, and orbital eccentricity), whose relative ratios in periodicity change over time as a function of a decreasing Earth spin rate and increasing lunar distance. However, for the critical older portion of Earth's history where information on Earth-Moon dynamics is sparse, suitable sedimentary successions in which these cycles are recorded remain largely unknown, leaving this method unexplored. Here we present results of cyclostratigraphic analysis and high-precision U-Pb zircon dating of the lower Paleoproterozoic Joffre Member of the Brockman Iron Formation, NW Australia, providing evidence for Milankovitch forcing of regular lithological alternations related to Earth's climatic precession and orbital eccentricity cycles. Combining visual and statistical tools to determine their hierarchical relation, we estimate an astronomical precession frequency of 108.6 ± 8.5 arcsec/y, corresponding to an Earth-Moon distance of 321,800 ± 6,500 km and a daylength of 16.9 ± 0.2 h at 2.46 Ga. With this robust cyclostratigraphic approach, we extend the oldest reliable datum for the lunar recession history by more than 1 billion years and provide a critical reference point for future modeling and geological investigation of Precambrian Earth-Moon system evolution.

6.
Bioscience ; 74(8): 561-566, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39229623

RESUMEN

Earth's biodiversity is increasingly threatened and at risk. We propose a passive lunar biorepository for long-term storage of prioritized taxa of live cryopreserved samples to safeguard Earth's biodiversity and to support future space exploration and planet terraforming. Our initial focus will be on cryopreserving animal skin samples with fibroblast cells. An exemplar system has been developed using cryopreserved fish fins from the Starry Goby, Asterropteryx semipunctata. Samples will be expanded into fibroblast cells, recryopreserved, and then tested in an Earth-based laboratory for robust packaging and sensitivity to radiation. Two key factors for this biorepository are the needs to reduce damage from radiation and to maintain the samples near -196° Celsius. Certain lunar sites near the poles may meet these criteria. If possible, further testing would occur on the International Space Station prior to storage on the Moon. To secure a positive shared future, this is an open call to participate in this decades-long program.

7.
Philos Trans A Math Phys Eng Sci ; 382(2271): 20230080, 2024 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-38522459

RESUMEN

Motivated by efforts to return humanity to the Moon, three cases are reviewed for X-ray astronomy from the lunar surface: (i) facilitation of ambitious engineering designs including high-throughput telescopes, long focal length optics and X-ray interferometery; (ii) occultation studies and the gain they enable in astrometric precision; and (iii) multi-messenger time-domain coordinated observations. The potential benefits of, and challenges presented by, operating from the Moon are discussed. Some of these cases have relatively low mass budgets and could be conducted as early pathfinders, while others are more ambitious and will likely need to await improvements in technology or well-developed lunar bases. This article is part of a discussion meeting issue 'Astronomy from the Moon: the next decades (part 2)'.

8.
Philos Trans A Math Phys Eng Sci ; 382(2271): 20230075, 2024 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-38522460

RESUMEN

The Moon has no atmosphere, hence, it offers a unique opportunity to place telescopes on its surface for astronomical observations. It is phase-locked with Earth, and its far side remains free from ground-based interference, enabling the optimal use of radio telescopes. However, the surface of the Moon, as any other airless planetary object in the solar system, is continually bombarded by interplanetary dust particles that cause impact damage and generate secondary ejecta particles that continually overturn the top layer of the lunar regolith. In addition, there is evidence, that small particles comprising the lunar regolith can be electrically charged, mobilized and transported, also representing a hazard for covering sensitive surfaces and interfering with exposed mechanical structures. In addition to the naturally occurring dust transport, rocket firings during landings and take-offs, pedestrian and motorized vehicle traffic will also liberate copious amounts of dust, representing a potential hazard for the safe and optimal use of optical platforms. This article is part of a discussion meeting issue 'Astronomy from the Moon: the next decades (part 2)'.

9.
Philos Trans A Math Phys Eng Sci ; 382(2271): 20230311, 2024 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-38522469

RESUMEN

The Moon is a unique natural laboratory for the study of the deep space plasma and energetic particles environment. During more than 3/4 of its orbit around the Earth it is exposed to the solar wind. Being an unmagnetized body and lacking a substantial atmosphere, solar wind and solar energetic particles bombard the Moon's surface, interacting with the lunar regolith and the tenuous lunar exosphere. Energetic particles arriving at the Moon's surface can be absorbed, or scattered, or can remove another particle from the lunar regolith by sputtering or desorption. A similar phenomenon occurs also with the galactic cosmic rays, which have fluxes and energy spectra representative of interplanetary space. During the remaining part of its orbit the Moon crosses the tail of the terrestrial magnetosphere. It then provides the opportunity to study in-situ the terrestrial magnetotail plasma environment as well as atmospheric escape from the Earth's ionosphere, in the form of heavy ions accelerated and streaming downtail. The lunar environment is thus a unique natural laboratory for analysing the interaction of the solar wind, the cosmic rays and the Earth's magnetosphere with the surface, the immediate subsurface, and the surface-bounded exosphere of an unmagnetized planetary body. This article is part of a discussion meeting issue 'Astronomy from the Moon: the next decades (part 2)'.

10.
Philos Trans A Math Phys Eng Sci ; 382(2271): 20230078, 2024 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-38522464

RESUMEN

The Moon presents unique opportunities for high-impact astronomy that could enhance our understanding of our solar system, the possibility of life beyond Earth, and the evolution of the universe. A handful of locations on the lunar surface are 'sites of extraordinary scientific importance' (SESIs) for such studies, presenting opportunities for astronomical research unmatched anywhere else. For instance, the farside of the Moon, the most radio-quiet location in the inner solar system, could allow for the emplacement of telescopes to study the cosmic Dark Ages in ways that are impossible elsewhere. However, we are also on the cusp of a broader lunar renaissance. A flurry of upcoming missions, both scientific and non-scientific, will target some of these very same sites and threatens to degrade their value to science. Protecting these sites is an urgent matter. Two major international efforts to create rules for activities on the Moon are afoot, but so far neither emphasizes protecting SESIs. To safeguard the exceptional scientific opportunities on the Moon, astronomers should engage these international rulemaking efforts and steer them towards ensuring the preservation of SESIs for research and discovery. We propose elements of a programme of action to adopt during a crucial, but closing, window. This article is part of a discussion meeting issue 'Astronomy from the Moon: the next decades (part 2)'.

11.
BMC Pregnancy Childbirth ; 24(1): 454, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38951765

RESUMEN

OBJECTIVE: The Moon has a noticeable influence on the Earth due to its gravity, the most visible manifestation of which are tides. We aimed to see if the Moon's daily cycle, like the Sun's, affects the prevalence and incidence of childbirth. METHODS: In this retrospective cohort study, we examined all deliveries at the Academic Hospital of Udine between 2001 and 2019. All consecutive singleton pregnancies with spontaneous labor and vaginal delivery were included. RESULTS: During the period, 13,349 singleton pregnancies with spontaneous labor and vaginal delivery were delivered in 6939 days. A significantly higher prevalence of deliveries was found with the Moon above the horizon (50.63% vs. 49.37%, p < 0.05). Moreover, during the day, there was a significantly higher prevalence of deliveries than during nighttime (53.74% vs. 45.79%, p < 0.05). Combining the Moon and Sun altitude, the majority of deliveries were registered when both were above the horizon (27.39% vs. 26.13%, 23.25%, or 23.24%, p < 0.05). These findings were confirmed in multivariate analysis after adjusting for parity, gestational age, or season. We found no correlation between birth and the Moon phase. CONCLUSIONS: Our data support the interaction of the Moon and the Sun in determining the time of birth. More research is needed to understand these phenomena and improve our understanding of labor initiation mechanisms.


Asunto(s)
Tasa de Natalidad , Luna , Humanos , Femenino , Estudios Retrospectivos , Embarazo , Adulto , Tasa de Natalidad/tendencias , Luz Solar , Parto Obstétrico/estadística & datos numéricos , Parto Obstétrico/métodos , Parto
12.
Proc Natl Acad Sci U S A ; 118(12)2021 03 23.
Artículo en Inglés | MEDLINE | ID: mdl-33723067

RESUMEN

Rocks from the lunar interior are depleted in moderately volatile elements (MVEs) compared to terrestrial rocks. Most MVEs are also enriched in their heavier isotopes compared to those in terrestrial rocks. Such elemental depletion and heavy isotope enrichments have been attributed to liquid-vapor exchange and vapor loss from the protolunar disk, incomplete accretion of MVEs during condensation of the Moon, and degassing of MVEs during lunar magma ocean crystallization. New Monte Carlo simulation results suggest that the lunar MVE depletion is consistent with evaporative loss at 1,670 ± 129 K and an oxygen fugacity +2.3 ± 2.1 log units above the fayalite-magnetite-quartz buffer. Here, we propose that these chemical and isotopic features could have resulted from the formation of the putative Procellarum basin early in the Moon's history, during which nearside magma ocean melts would have been exposed at the surface, allowing equilibration with any primitive atmosphere together with MVE loss and isotopic fractionation.

13.
Sensors (Basel) ; 24(8)2024 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-38676196

RESUMEN

As a natural satellite of the Earth, the moon is a prime target for planetary remote sensing exploration. However, lunar polarization studies are not popular in the planetary science community. Polarimetry of the lunar surface had not been carried out from a spacecraft until the Korean lunar exploration program was initiated. In previous polarization observations of the moon, images of different polarization states were obtained by a rotating linear polarizer. This method is not well suited for future polarization observations from space-based spacecraft. To this end, we present a new kind of polarized observation of the moon using a division of a focal-plane polarization camera and propose a pipeline on the processing method of the polarization observation of the moon. We obtain a map of the degree of white-light polarization on the nearside of the moon through polarization observation, data processing, and correction. The observation and data processing methods presented in this study have the potential to serve as a reference for analyzing polarization observation data from future orbiting spacecraft. These are expected to lead to new discoveries in the fields of astronomy and planetary science.

14.
Crit Rev Toxicol ; 53(8): 441-479, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37850621

RESUMEN

The mechanisms of particle-induced pathogenesis in the lung remain poorly understood. Neutrophilic inflammation and oxidative stress in the lung are hallmarks of toxicity. Some investigators have postulated that oxidative stress from particle surface reactive oxygen species (psROS) on the dust produces the toxicopathology in the lungs of dust-exposed animals. This postulate was tested concurrently with the studies to elucidate the toxicity of lunar dust (LD), which is believed to contain psROS due to high-speed micrometeoroid bombardment that fractured and pulverized lunar surface regolith. Results from studies of rats intratracheally instilled (ITI) with three LDs (prepared from an Apollo-14 lunar regolith), which differed 14-fold in levels of psROS, and two toxicity reference dusts (TiO2 and quartz) indicated that psROS had no significant contribution to the dusts' toxicity in the lung. Reported here are results of further investigations by the LD toxicity study team on the toxicological role of oxidants in alveolar neutrophils that were harvested from rats in the 5-dust ITI study and from rats that were exposed to airborne LD for 4 weeks. The oxidants per neutrophils and all neutrophils increased with dose, exposure time and dust's cytotoxicity. The results suggest that alveolar neutrophils play a critical role in particle-induced injury and toxicity in the lung of dust-exposed animals. Based on these results, we propose an adverse outcome pathway (AOP) for particle-associated lung disease that centers on the crucial role of alveolar neutrophil-derived oxidant species. A critical review of the toxicology literature on particle exposure and lung disease further supports a neutrophil-centric mechanism in the pathogenesis of lung disease and may explain previously reported animal species differences in responses to poorly soluble particles. Key findings from the toxicology literature indicate that (1) after exposures to the same dust at the same amount, rats have more alveolar neutrophils than hamsters; hamsters clear more particles from their lungs, consequently contributing to fewer neutrophils and less severe lung lesions; (2) rats exposed to nano-sized TiO2 have more neutrophils and more severe lesions in their lungs than rats exposed to the same mass-concentration of micron-sized TiO2; nano-sized dust has a greater number of particles and a larger total particle-cell contact surface area than the same mass of micron-sized dust, which triggers more alveolar epithelial cells (AECs) to synthesize and release more cytokines that recruit a greater number of neutrophils leading to more severe lesions. Thus, we postulate that, during chronic dust exposure, particle-inflicted AECs persistently release cytokines, which recruit neutrophils and activate them to produce oxidants resulting in a prolonged continuous source of endogenous oxidative stress that leads to lung toxicity. This neutrophil-driven lung pathogenesis explains why dust exposure induces more severe lesions in rats than hamsters; why, on a mass-dose basis, nano-sized dusts are more toxic than the micron-sized dusts; why lung lesions progress with time; and why dose-response curves of particle toxicity exhibit a hockey stick like shape with a threshold. The neutrophil centric AOP for particle-induced lung disease has implications for risk assessment of human exposures to dust particles and environmental particulate matter.


Asunto(s)
Polvo , Enfermedades Pulmonares , Cricetinae , Ratas , Humanos , Animales , Neutrófilos/patología , Pulmón , Citocinas/toxicidad , Oxidantes/toxicidad , Tamaño de la Partícula
15.
J Sleep Res ; 32(2): e13635, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-35567349

RESUMEN

In adults, recent evidence demonstrates that sleep and circadian physiology change across lunar phases, including findings that endogenous melatonin levels are lower near the full moon compared to the new moon. Here, we extend these results to early childhood by examining circalunar fluctuations in children's evening melatonin levels. We analysed extant data on young children's circadian rhythms (n = 46, aged 3.0-5.9 years, 59% female). After following a strict sleep schedule for 5-7 days, children completed an in-home, dim-light circadian assessment (<10 lux). Salivary melatonin was assessed at regular 20- to 30-min intervals until 1 h past each child's scheduled bedtime. Melatonin levels varied significantly across lunar phases, such that melatonin was lower in participants assessed near the full moon as compared to near the new moon. Significant differences were observed at 50 min (meanfull  = 2.5 pg/ml; meannew  = 5.4 pg/ml) and 10 min (meanfull  = 7.3 pg/ml; meannew  = 15.8 pg/ml) before children's scheduled bedtime, as well as at 20 min (meanfull  = 15.5 pg/ml; meannew  = 26.1 pg/ml) and 50 min (meanfull  = 19.9 pg/ml; meannew  = 34.3 pg/ml) after bedtime. To our knowledge, these are the first data demonstrating that melatonin secretion, a process regulated by the human circadian system, is sensitive to changes in lunar phase at an early age. Future research is needed to understand the mechanisms underlying this association (e.g., an endogenous circalunar rhythm) and its potential influence on children's sleep and circadian health.


Asunto(s)
Melatonina , Adulto , Humanos , Niño , Preescolar , Femenino , Masculino , Melatonina/análisis , Ritmo Circadiano/fisiología , Sueño/fisiología , Luz
16.
Inhal Toxicol ; 35(5-6): 139-156, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36966416

RESUMEN

NASA is currently planning return missions to the Moon for further exploration and research. The Moon is covered by a layer of potentially reactive fine dust, which could pose a toxicological risk of exposure to explorers. To assess this risk, we exposed rats to lunar dust (LD) that was collected during the Apollo14 mission. Rats were exposed to respirable sizes of LD at concentrations of 0, 2.1, 6.8, 20.8, or 60.6 mg/m3 for 4 weeks. At thirteen weeks after exposure, we assessed 44,000 gene transcripts and found the expression of 614 genes with known functions were significantly altered in the rats exposed to the 2 higher concentrations of LD, whereas few changes in gene expression were detected in the group exposed to the lowest concentration of LD. Many of the significant changes in gene expression involved genes known to be associated with inflammation or fibrosis. Four genes encoding pro-inflammatory chemokines were analyzed further for all the sampling points at 1 day, and 1, 4, and 13 weeks after the 4-week dust exposure, using real-time polymerase chain reaction. The expression of these genes was altered in a dose- and time-dependent manner and persistently changed in the lungs of the rats exposed to the two higher concentrations of LD. Their expressions are consistent with changes we detected in pulmonary toxicity biomarkers and pathology in these animals during a previous study. Because Apollo-14 LD contains common mineral oxides similar to an Arizona volcanic ash, besides revealing the toxicity of LD, our findings could help elucidate the genomic and molecular mechanisms involved in pulmonary toxicity induced by terrestrial mineral dusts.


Asunto(s)
Polvo , Enfermedades Pulmonares , Ratas , Animales , Polvo/análisis , Luna , Pulmón/patología , Enfermedades Pulmonares/patología , Inflamación/patología , Fibrosis
17.
Proc Natl Acad Sci U S A ; 117(26): 14764-14768, 2020 06 30.
Artículo en Inglés | MEDLINE | ID: mdl-32546519

RESUMEN

The ice shell on Enceladus, an icy moon of Saturn, exhibits strong asymmetry between the northern and southern hemispheres, with all known geysers concentrated over the south pole, even though the expected pattern of tidal forced deformation should be symmetric between the north and south poles. Using an idealized ice-evolution model, we demonstrate that this asymmetry may form spontaneously, without any noticeable a priori asymmetry (such as a giant impact or a monopole structure of geological activity), in contrast to previous studies. Infinitesimal asymmetry in the ice shell thickness due to random perturbations are found to be able to grow indefinitely, ending up significantly thinning the ice shell at one of the poles, thereby allowing fracture formation there. Necessary conditions to trigger this hemispheric symmetry-breaking mechanism are found analytically. A rule of thumb we find is that, for Galilean and Saturnian icy moons, the ice shell can undergo hemispheric symmetry breaking only if the mean shell thickness is around 10 to 30 km.

18.
Proc Natl Acad Sci U S A ; 117(27): 15460-15464, 2020 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-32571906

RESUMEN

The Moon likely formed in a giant impact that left behind a fast-rotating Earth, but the details are still uncertain. Here, we examine the implications of a constraint that has not been fully exploited: The component of the Earth-Moon system's angular momentum that is perpendicular to the Earth's orbital plane is nearly conserved in Earth-Moon history, except for possible intervals when the lunar orbit is in resonance with the Earth's motion about the Sun. This condition sharply constrains the postimpact Earth orientation and the subsequent lunar orbital history. In particular, the scenario involving an initial high-obliquity Earth cannot produce the present Earth-Moon system. A low-obliquity postimpact Earth followed by the evection limit cycle in orbital evolution remains a possible pathway for producing the present angular momentum and observed lunar composition.

19.
Cult Health Sex ; 25(8): 947-959, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-35994692

RESUMEN

In many South Asian contexts, specific dates are auspicious and inauspicious for health-related behaviours and outcomes. This study analysed the effect of lunar date-related auspicious beliefs in Nepal on childbirths and neonatal health outcomes. Using the daily birth records from a tertiary maternity hospital, we empirically examined whether births occurred disproportionally around full moon days. We found an average of 10.7 extra births on and before full moon days, with an average of 7.5 extra Caesarean deliveries on full moon days. We demonstrated that births occurring on or before the full moon day have poor neonatal health outcomes. However, a subsample analysis suggested better health outcomes for low-risk mothers and worse health outcomes for high-risk mothers. These findings suggest that low-risk mothers may move their deliveries to auspicious dates with fewer complications than high-risk mothers. The results emphasise the need for additional research to distinguish health service demand from supply influences on birth timing in Nepal.


Asunto(s)
Salud Infantil , Luna , Recién Nacido , Niño , Humanos , Embarazo , Femenino , Nepal , Parto , Madres
20.
J Shoulder Elbow Surg ; 32(3): 533-538, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36179960

RESUMEN

BACKGROUND: Previous studies have demonstrated that psychosocial factors and comorbid depression are associated with worse preoperative baseline measures, clinical outcomes, and recovery in patients undergoing shoulder surgery. It is unknown whether this potential link would differ between those with traumatic vs. atraumatic shoulder instability, as symptoms may persist longer in atraumatic instability prior to surgical intervention. The purpose of this study was to determine if psychosocial factors and/or comorbid depression more heavily influence preoperative symptoms for patients with traumatic vs. atraumatic shoulder instability. METHODS: Prospective baseline data from 1552 patients in the Multicenter Orthopaedic Outcomes Network (MOON) Shoulder Instability cohort were analyzed based on mechanism of injury while controlling for age, sex, and direction of instability. Multivariable linear regressions were performed to determine whether psychological factors (RAND 36 Mental Component Score [MCS], depression diagnosis, Personality Assessment Screener-22) were predictive of preoperative American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form (ASES) and Western Ontario Shoulder Instability Index (WOSI) scores in the atraumatic group. The same model was repeated for the traumatic instability group, and the model fit was compared between groups, with P < .05 considered statistically significant. RESULTS: Female sex and lower MCS were significantly associated with worse preoperative ASES and WOSI scores for the group with atraumatic instability (ASES R2 = 0.15, P < .001; WOSI R2 = 0.17, P < .001). The same model performed significantly worse (P < .05) for both ASES and WOSI scores in the group with traumatic instability (ASES R2 = 0.07, WOSI R2 = 0.08). CONCLUSIONS: Worse preoperative psychosocial factors were found to be more strongly associated with shoulder-related pain and function for patients with atraumatic instability. Across multiple orthopedic conditions, depression and emotional well-being have been associated with worse preoperative symptoms and inferior postoperative patient-reported outcomes. Despite the stronger and significant association in atraumatic patients, worse psychosocial factors did not have as large an impact as has been seen in other, more chronic conditions such as osteoarthritis or rotator cuff tears. In addition to medically optimizing patients prior to surgery, the current findings identify a subset of shoulder instability patients that may benefit from a behavioral health intervention either prior to surgery or early in the postoperative period to potentially improve postoperative outcomes.


Asunto(s)
Inestabilidad de la Articulación , Ortopedia , Articulación del Hombro , Humanos , Femenino , Hombro , Articulación del Hombro/cirugía , Inestabilidad de la Articulación/cirugía , Estudios Prospectivos , Artroscopía , Dolor de Hombro , Resultado del Tratamiento
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