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1.
Proc Natl Acad Sci U S A ; 119(27): e2201139119, 2022 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-35759667

RESUMO

The Sample Analysis at Mars instrument stepped combustion experiment on a Yellowknife Bay mudstone at Gale crater, Mars revealed the presence of organic carbon of Martian and meteoritic origins. The combustion experiment was designed to access refractory organic carbon in Mars surface sediments by heating samples in the presence of oxygen to combust carbon to CO2. Four steps were performed, two at low temperatures (less than ∼550 °C) and two at high temperatures (up to ∼870 °C). More than 950 µg C/g was released at low temperatures (with an isotopic composition of δ13C = +1.5 ± 3.8‰) representing a minimum of 431 µg C/g indigenous organic and inorganic Martian carbon components. Above 550 °C, 273 ± 30 µg C/g was evolved as CO2 and CO (with estimated δ13C = -32.9‰ to -10.1‰ for organic carbon). The source of high temperature organic carbon cannot be definitively confirmed by isotopic composition, which is consistent with macromolecular organic carbon of igneous origin, meteoritic infall, or diagenetically altered biomass, or a combination of these. If from allochthonous deposition, organic carbon could have supported both prebiotic organic chemistry and heterotrophic metabolism at Gale crater, Mars, at ∼3.5 Ga.

2.
Alcohol Alcohol ; 59(2)2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-37968937

RESUMO

INTRODUCTION: This study utilizes a machine learning model to predict unhealthy alcohol use treatment levels among women of childbearing age. METHODS: In this cross-sectional study, women of childbearing age (n = 2397) were screened for alcohol use over a 2-year period as part of the AL-SBIRT (screening, brief intervention, and referral to treatment in Alabama) program in three healthcare settings across Alabama for unhealthy alcohol use severity and depression. A support vector machine learning model was estimated to predict unhealthy alcohol use scores based on depression score and age. RESULTS: The machine learning model was effective in predicting no intervention among patients with lower Patient Health Questionnaire (PHQ)-2 scores of any age, but a brief intervention among younger patients (aged 18-27 years) with PHQ-2 scores >3 and a referral to treatment for unhealthy alcohol use among older patients (between the ages of 25 and 50) with PHQ-2 scores >4. CONCLUSIONS: The machine learning model can be an effective tool in predicting unhealthy alcohol use treatment levels and approaches.


Assuntos
Alcoolismo , Humanos , Feminino , Adulto , Pessoa de Meia-Idade , Adolescente , Adulto Jovem , Alcoolismo/diagnóstico , Alcoolismo/epidemiologia , Alcoolismo/prevenção & controle , Alabama/epidemiologia , Estudos Transversais , Consumo de Bebidas Alcoólicas/epidemiologia , Encaminhamento e Consulta
3.
Clin Infect Dis ; 75(12): 2250-2252, 2022 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-35653425

RESUMO

A patient was diagnosed with Brucella canis following exposure to infected dogs in her breeding facility. Transboundary spread of B. canis through (illegal) import of infected dogs to non-endemic countries in Europe suggest that B. canis infection should be considered in European patients with occupational exposure to dogs.


Assuntos
Brucella canis , Brucelose , Doenças do Cão , Animais , Cães , Feminino , Humanos , Brucelose/diagnóstico , Brucelose/veterinária , Doenças do Cão/diagnóstico , Europa (Continente) , Países Baixos
4.
Bull Math Biol ; 83(7): 73, 2021 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-34008062

RESUMO

A central need in the field of astrobiology is generalized perspectives on life that make it possible to differentiate abiotic and biotic chemical systems McKay (2008). A key component of many past and future astrobiological measurements is the elemental ratio of various samples. Classic work on Earth's oceans has shown that life displays a striking regularity in the ratio of elements as originally characterized by Redfield (Redfield 1958; Geider and La Roche 2002; Eighty years of Redfield 2014). The body of work since the original observations has connected this ratio with basic ecological dynamics and cell physiology, while also documenting the range of elemental ratios found in a variety of environments. Several key questions remain in considering how to best apply this knowledge to astrobiological contexts: How can the observed variation of the elemental ratios be more formally systematized using basic biological physiology and ecological or environmental dynamics? How can these elemental ratios be generalized beyond the life that we have observed on our own planet? Here, we expand recently developed generalized physiological models (Kempes et al. 2012, 2016, 2017, 2019) to create a simple framework for predicting the variation of elemental ratios found in various environments. We then discuss further generalizing the physiology for astrobiological applications. Much of our theoretical treatment is designed for in situ measurements applicable to future planetary missions. We imagine scenarios where three measurements can be made-particle/cell sizes, particle/cell stoichiometry, and fluid or environmental stoichiometry-and develop our theory in connection with these often deployed measurements.


Assuntos
Exobiologia , Conceitos Matemáticos
5.
Euro Surveill ; 23(9)2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29510783

RESUMO

Background and aimsPriority setting is a challenging task for public health professionals. To support health professionals with this and in following a recommendation from the Food and Agriculture Organization of the United Nations (FAO) and World Health Organization (WHO), 35 European parasitologists attended a workshop from 8-12 February 2016 to rank food-borne parasites (FBP) in terms of their importance for Europe and regions within Europe. Methods: Countries were divided into European regions according to those used by the European Society of Clinical Microbiology and Infectious Diseases. We used the same multicriteria decision analysis approach as the FAO/WHO, for comparison of results, and a modified version, for better regional representation. Twenty-five FBP were scored in subgroups, using predefined decision rules. Results: At the European level, Echinococcus multilocularis ranked first, followed by Toxoplasma gondii and Trichinella spiralis. At the regional level, E. multilocularis ranked highest in Northern and Eastern Europe, E. granulosus in South-Western and South-Eastern Europe, and T. gondii in Western Europe. Anisakidae, ranking 17th globally, appeared in each European region's top 10. In contrast, Taenia solium, ranked highest globally but 10th for Europe. Conclusions: FBP of importance in Europe differ from those of importance globally, requiring targeted surveillance systems, intervention measures, and preparedness planning that differ across the world and across Europe.


Assuntos
Parasitologia de Alimentos , Doenças Transmitidas por Alimentos/classificação , Doenças Transmitidas por Alimentos/parasitologia , Prioridades em Saúde , Parasitos/classificação , Animais , Europa (Continente)/epidemiologia , Doenças Transmitidas por Alimentos/epidemiologia , Humanos , Parasitos/patogenicidade , Saúde Pública
6.
Artigo em Inglês | MEDLINE | ID: mdl-39057842

RESUMO

AIMS: Zoonotic arboviruses (arthropod-borne) of the Orthoflavivirus genus, such as West Nile virus (WNV), Usutu virus (USUV) and Tick-borne encephalitis virus (TBEV), are emerging in Northwestern Europe and pose a threat to both human and animal health. In the Netherlands, passive symptomatic surveillance (notification of clinical cases) in horses is one of the main pillars for the early detection of WNV. For such passive surveillance to work properly, horse owners and veterinarians need to recognize symptoms and report suspected cases to the authorities. Currently, little is known about the seroprevalence of orthoflaviviruses in domestic animals in the Netherlands. Therefore, this study aims at identifying the seroprevalence of WNV and USUV in horses and dogs in the Netherlands. Additionally, this study seeks to evaluate the knowledge and perceptions of Dutch horse owners towards mosquito-borne viruses. METHODS AND RESULTS: A cross-sectional serosurvey in horses and dogs was conducted between May 2021 and May 2022. Serum samples were screened using an ELISA and doubtful and positive samples were confirmed by Virus Neutralization Tests for WNV, USUV and TBEV. A validated questionnaire, the MosquitoWise survey, was used to assess the knowledge and perceptions of Dutch horse owners towards mosquito-borne viruses between July and October 2022. The serosurvey revealed a low seroprevalence for WNV in horses and no WNV-positive dogs were found. Similarly, a low USUV seroprevalence was found in dogs. The MosquitoWise survey revealed a high knowledge level for horse owners and high awareness of WNV vaccination but a more limited intent to vaccinate. CONCLUSIONS: The low seroprevalences of WNV and USUV indicate many dogs and horses remain susceptible, offering opportunities for trend analysis and surveillance. However, despite multiple recent detections of WNV, USUV, and TBEV in humans, the role of dogs and horses in early detection of human cases is debatable. High awareness among horse owners and the absence of detected equine WNV cases highlight this uncertainty. Continued surveillance is crucial for detecting increased virus circulation and protecting both animal and human health.

7.
Vet Microbiol ; 296: 110183, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38991314

RESUMO

Brucella canis is a zoonotic pathogen and the main causative agent of canine brucellosis. In the Netherlands, B. canis had previously only been detected in individual cases of imported dogs. However, an outbreak of B. canis occurred for the first time in a cohort of autochthonous dogs in a breeding kennel in 2019. The outbreak began with a positive serological test result of an imported intact male dog showing clinical symptoms of brucellosis. Consequently, urine and blood samples were collected and tested positive for B. canis by culture, matrix-assisted laser desorption/ionization - time of flight mass spectrometry (MALDI-TOF MS) and whole-genome-sequencing (WGS). Screening of the contact dogs in the kennel where the index case was kept, revealed that antibodies against B. canis could be detected in 23 out of 69 dogs (34 %) by serum agglutination test (SAT). Of the 23 seropositive dogs, B. canis could be cultured from the urine and/or heparin samples of 19 dogs (83 %). This outbreak represents the first documented case of transmission of B. canis to autochthonous contact dogs in the Netherlands. WGS revealed all B. canis isolates belonged to the same cluster, which means the transmission of B. canis in the breeding kennel was most likely caused by the introduction of one infected dog. Comparing this cluster with data from other B. canis isolates, it also appears that characteristic clusters of B. canis are present in several endemic countries. These clusters seem to remain stable over time and may help in locating the origin of new isolates found. This outbreak showed that the international movement of dogs from endemic countries poses a threat to the canine population, while serological screening and WGS proved to be valuable tools for respectively screening and the epidemiological investigation.

8.
Front Digit Health ; 5: 1222187, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37829593

RESUMO

Autism continues to be a leading neurodevelopmental disorder across adult and pediatric populations that transcends racial, ethnic, age, and socioeconomic groups worldwide. Autism care and treatment also exerts immense costs on the healthcare system and lost productivity which are partly attributed to the existing resource limitations globally. Organizations, campaigns, and policies exist worldwide in increasing equity and accessibility of resources and services to individuals with autism. In the context of our digital era, a wealth of information is also more readily available on autism through electronic communication including social media platforms. As YouTube, Twitter and Facebook are ever-growing and among the leading social media platforms in contemporary times, examination of content covered on autism across these communication mediums is timely and warranted. This review consolidates findings from 32 sources on the sources, formats, and nature of content covered on YouTube, Twitter, and Facebook pertaining to a wealth of dimensions surrounding autism. Strengths and limitations of the studies and endeavors are presented. Implications for future campaign development, health equity, health policy, neurodiversity, and patient care are also delineated. Lastly, recommendations for future research and practice are discussed which present directions for tapping into the potential of YouTube, Twitter, and Facebook as health communication mediums across the ever-changing autism landscape.

9.
Healthcare (Basel) ; 11(8)2023 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-37107900

RESUMO

This study examines cross-sectional clusters and longitudinal predictions using an expanded SAVA syndemic conceptual framework-SAVA MH + H (substance use, intimate partner violence, mental health, and homelessness leading to HIV/STI/HCV risks)-among women recently released from incarceration (WRRI) (n = 206) participating in the WORTH Transitions (WT) intervention. WT combines two evidence-based interventions: the Women on the Road to Health HIV intervention, and Transitions Clinic. Cluster analytic and logistic regression methods were utilized. For the cluster analyses, baseline SAVA MH + H variables were categorized into presence/absence. For logistic regression, baseline SAVA MH + H variables were examined on a composite HIV/STI/HCV outcome collected at 6-month follow-up, controlling for lifetime trauma and sociodemographic characteristics. Three SAVA MH + H clusters were identified, the first of which had women with the highest overall levels of SAVA MH + H variables, 47% of whom were unhoused. Hard drug use (HDU) was the only significant predictor of HIV/STI/HCV risks in the regression analyses. HDUs had 4.32-fold higher odds of HIV/STI/HCV outcomes than non-HDUs (p = 0.002). Interventions such as WORTH Transitions must differently target identified SAVA MH + H syndemic risk clusters and HDU to prevent HIV/HCV/STI outcomes among WRRI.

10.
Science ; 379(6634): eabn9033, 2023 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-36821691

RESUMO

The Hayabusa2 spacecraft collected samples from the surface of the carbonaceous near-Earth asteroid (162173) Ryugu and brought them to Earth. The samples were expected to contain organic molecules, which record processes that occurred in the early Solar System. We analyzed organic molecules extracted from the Ryugu surface samples. We identified a variety of molecules containing the atoms CHNOS, formed by methylation, hydration, hydroxylation, and sulfurization reactions. Amino acids, aliphatic amines, carboxylic acids, polycyclic aromatic hydrocarbons, and nitrogen-heterocyclic compounds were detected, which had properties consistent with an abiotic origin. These compounds likely arose from an aqueous reaction on Ryugu's parent body and are similar to the organics in Ivuna-type meteorites. These molecules can survive on the surfaces of asteroids and be transported throughout the Solar System.

11.
Science ; 382(6677): 1411-1416, 2023 12 22.
Artigo em Inglês | MEDLINE | ID: mdl-38127762

RESUMO

Polycyclic aromatic hydrocarbons (PAHs) contain ≲20% of the carbon in the interstellar medium. They are potentially produced in circumstellar environments (at temperatures ≳1000 kelvin), by reactions within cold (~10 kelvin) interstellar clouds, or by processing of carbon-rich dust grains. We report isotopic properties of PAHs extracted from samples of the asteroid Ryugu and the meteorite Murchison. The doubly-13C substituted compositions (Δ2×13C values) of the PAHs naphthalene, fluoranthene, and pyrene are 9 to 51‰ higher than values expected for a stochastic distribution of isotopes. The Δ2×13C values are higher than expected if the PAHs formed in a circumstellar environment, but consistent with formation in the interstellar medium. By contrast, the PAHs phenanthrene and anthracene in Ryugu samples have Δ2×13C values consistent with formation by higher-temperature reactions.

12.
BMC Public Health ; 12: 838, 2012 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-23031437

RESUMO

BACKGROUND: Poor adherence to the oral contraceptive pill (OCP) is reported as one of the main causes of unintended pregnancy in women that rely on this form of contraception. This study aims to estimate the associations between a range of well-established modifiable psychological factors and adherence to OCP. METHOD: A cross-sectional survey of 130 female University students currently using OCP (Mean age: 20.46 SD: 3.01, range 17-36) was conducted. An OCP specific Medication Adherence Report Scale was used to assess non-adherence. Psychological predictor measures included necessity and concern beliefs about OCP, intentions, perceived behavioural control (pbc), anticipated regret and action and coping planning. Multiple linear regression was used to analyse the data. RESULTS: Fifty-two per cent of participants reported missing their OCP once or more per month and 14% twice or more per month. In bivariate analysis intentions (r = -0.25), perceived behavioural control (r= -0.66), anticipated regret (r=0.20), concerns about OCP (r =0.31), and action (r= -0.25) and coping (r= -0.28) planning were all significantly associated with adherence to OCP in the predicted direction. In a multivariate model almost half (48%) of the variation in OCP adherence could be explained. The strongest and only statistically significant predictors in this model were perceived behavioural control (ß=-0.62, p<0.01) and coping planning (ß =-0.23, p=0.03). A significant interaction between intentions and anticipated regret was also observed. CONCLUSION: The present data point to a number of key modifiable psychological determinants of OCP use. Future work will establish whether changing these variables results in better adherence to the OCP.


Assuntos
Anticoncepcionais Orais Hormonais/administração & dosagem , Adesão à Medicação/psicologia , Adolescente , Adulto , Intervalos de Confiança , Estudos Transversais , Feminino , Comportamentos Relacionados com a Saúde , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Razão de Chances , Análise de Regressão , Adulto Jovem
13.
Front Vet Sci ; 9: 954046, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36299627

RESUMO

Equine piroplasmosis (EP) is a tick-borne disease affecting horses, donkeys, mules and zebras, caused by the intracellular apicomplexan protozoa Babesia caballi and Theileria equi. The geographical distribution of EP is closely related to the distribution of its vector tick species belonging to the genera of Dermacentor, Rhipicephalus and Hyalomma. Since the discovery of Dermacentor reticulatus ticks in 2007 and the first reported autochthonous cases in the South of the Netherlands in 2012, no data on the (sero)prevalence of EP in horses in the Netherlands have been reported and it remains unclear whether B. caballi and T. equi have been able to establish themselves in the Netherlands. This study aims to give an update on the current status of EP in horses in the Netherlands using data from serological tests performed in the context of export and screening of 12,881 horses from 2015 through 2020. Horses were categorized as "Dutch," "Foreign," or "Unknown" based on microchip number. The overall seroprevalence of EP in Dutch horses was found to be 0.5% (95% exact CI [0.4-0.7]), compared to 1.9% (95% exact CI [1.3-2.6]) in horses in the category "Foreign" and 1.7% (95% exact CI [1.2-2.3]) in horses in the category "Unknown." In addition, the seroprevalence per country in the category "Foreign" ranged from 0% (0.95% exact CI [0-2.8]) for Ireland to 6.0% (0.95% exact CI [3.5-9.3]) for Spain. In light of the reports on the seroprevalence during the outbreak of autochthonous EP reported in 2012 and on seroprevalences of EP in other countries in Northwestern Europe, the seroprevalence of EP in horses exported from the Netherlands is very low. However, the higher seroprevalence of EP in horses from abroad warrants the need for the monitoring of EP, as tick vectors are present in the Netherlands and the import of horses from endemic areas increases the chances of EP becoming more prevalent in the Netherlands.

14.
Life (Basel) ; 12(9)2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-36143402

RESUMO

The stable isotope composition of soluble and insoluble organic compounds in carbonaceous chondrites can be used to determine the provenance of organic molecules in space. Deuterium enrichment in meteoritic organics could be a residual signal of synthetic reactions occurring in the cold interstellar medium or an indicator of hydrothermal parent-body reactions. δD values have been measured in grains and bulk samples for a wide range of meteorites; however, these reservoirs are highly variable and may have experienced fractionation during thermal and/or aqueous alteration. Among the plethora of organic compounds in meteorites are polycyclic aromatic hydrocarbons (PAHs), which are stable and abundant in carbonaceous chondrites, and their δD ratio may preserve evidence about their formation environment as well as the influence of parent-body processes. This study tests hypotheses about the potential links between PAHs-deuteration concentrations and their formation conditions by examining the δD ratio of PAHs in three CM carbonaceous chondrites representing an aqueous alteration gradient. We use deuterium enrichments in soluble 2-5-ring PAHs as an indicator of either photon-driven deuteration due to unimolecular photodissociation in warm regions of space, gas-phase ion-molecule reactions in cold interstellar regions of space, or UV photolysis in ices. We also test hypothesized reaction pathways during parent-body processing that differ between partially and fully aromatized PAHs. New methodological approaches were developed to extract small, volatile PAHs without fractionation. Our results suggest that meteoritic PAHs could have formed through reactions in cold regions, with possible overprinting of deuterium enrichment during aqueous parent-body alteration, but the data could not rule out PAH alteration in icy mantles as well.

15.
Astrobiology ; 22(8): 901-913, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35507950

RESUMO

Astrobiology missions to ocean worlds in our solar system must overcome both scientific and technological challenges due to extreme temperature and radiation conditions, long communication times, and limited bandwidth. While such tools could not replace ground-based analysis by science and engineering teams, machine learning algorithms could enhance the science return of these missions through development of autonomous science capabilities. Examples of science autonomy include onboard data analysis and subsequent instrument optimization, data prioritization (for transmission), and real-time decision-making based on data analysis. Similar advances could be made to develop streamlined data processing software for rapid ground-based analyses. Here we discuss several ways machine learning and autonomy could be used for astrobiology missions, including landing site selection, prioritization and targeting of samples, classification of "features" (e.g., proposed biosignatures) and novelties (uncharacterized, "new" features, which may be of most interest to agnostic astrobiological investigations), and data transmission.


Assuntos
Comunicação , Exobiologia , Oceanos e Mares , Sistema Solar , Temperatura
16.
Astrobiology ; 22(6): 637-640, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35196462

RESUMO

"Fungi on Mars!": a popular news heading that piques public interest and makes scientists' blood boil. While such a statement is laden with misinformation and light on evidence, the search for past and present extraterrestrial life is an ongoing scientific effort. Moreover, it is one that is increasingly gaining momentum with the recent collection of martian rock cores from Jezero Crater by NASA's Perseverance rover. Despite the increasingly sophisticated approaches guiding the search for microbial life on other planets, fungi remain relatively underexplored compared to their bacterial counterparts, highlighting a gap between the astrobiological and fungal research communities. Through a meeting in April 2021, the CIFAR Earth 4D and Fungal Kingdom research programs worked to bridge this divide by uniting experts in each field. CIFAR is a Canadian-based global research organization that convenes researchers across disciplines to address important questions facing science and humanity. The CIFAR Earth 4D: Subsurface Science & Exploration and Fungal Kingdom: Threats & Opportunities research programs were launched by CIFAR in July 2019, each made up of approximately two dozen international researchers who are experts in their fields. The Earth 4D program, led by co-directors John Mustard (Brown University, USA) and Barbara Sherwood Lollar (University of Toronto, Canada), aims to understand the complex chemical, physical, and biological interactions that occur within and between Earth's surface and subsurface to explore questions on the evolution of planets and life. The Fungal Kingdom program, led by co-directors Leah Cowen (University of Toronto, Canada) and Joseph Heitman (Duke University, USA), seeks to tackle the most pressing threats fungi pose to human health, agriculture, and biodiversity and to harness their extraordinary potential. The programs met to explore areas for synergy within four major themes: (1) the origins of life; (2) the evolution and diversification of life; (3) life in diverse and extreme environments; and (4) extinction: lessons learned and threats. This report covers the research discussed during the meeting across these four themes.


Assuntos
Meio Ambiente Extraterreno , Marte , Canadá , Planeta Terra , Exobiologia , Humanos , Planetas
17.
Astrobiology ; 22(S1): S186-S216, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35653292

RESUMO

The Committee on Space Research (COSPAR) Sample Safety Assessment Framework (SSAF) has been developed by a COSPAR appointed Working Group. The objective of the sample safety assessment would be to evaluate whether samples returned from Mars could be harmful for Earth's systems (e.g., environment, biosphere, geochemical cycles). During the Working Group's deliberations, it became clear that a comprehensive assessment to predict the effects of introducing life in new environments or ecologies is difficult and practically impossible, even for terrestrial life and certainly more so for unknown extraterrestrial life. To manage expectations, the scope of the SSAF was adjusted to evaluate only whether the presence of martian life can be excluded in samples returned from Mars. If the presence of martian life cannot be excluded, a Hold & Critical Review must be established to evaluate the risk management measures and decide on the next steps. The SSAF starts from a positive hypothesis (there is martian life in the samples), which is complementary to the null-hypothesis (there is no martian life in the samples) typically used for science. Testing the positive hypothesis includes four elements: (1) Bayesian statistics, (2) subsampling strategy, (3) test sequence, and (4) decision criteria. The test sequence capability covers self-replicating and non-self-replicating biology and biologically active molecules. Most of the investigations associated with the SSAF would need to be carried out within biological containment. The SSAF is described in sufficient detail to support planning activities for a Sample Receiving Facility (SRF) and for preparing science announcements, while at the same time acknowledging that further work is required before a detailed Sample Safety Assessment Protocol (SSAP) can be developed. The three major open issues to be addressed to optimize and implement the SSAF are (1) setting a value for the level of assurance to effectively exclude the presence of martian life in the samples, (2) carrying out an analogue test program, and (3) acquiring relevant contamination knowledge from all Mars Sample Return (MSR) flight and ground elements. Although the SSAF was developed specifically for assessing samples from Mars in the context of the currently planned NASA-ESA MSR Campaign, this framework and the basic safety approach are applicable to any other Mars sample return mission concept, with minor adjustments in the execution part related to the specific nature of the samples to be returned. The SSAF is also considered a sound basis for other COSPAR Planetary Protection Category V, restricted Earth return missions beyond Mars. It is anticipated that the SSAF will be subject to future review by the various MSR stakeholders.


Assuntos
Marte , Voo Espacial , Teorema de Bayes , Meio Ambiente Extraterreno , Pesquisa Espacial
18.
Nat Commun ; 12(1): 3033, 2021 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-34031398

RESUMO

The search for alien life is hard because we do not know what signatures are unique to life. We show why complex molecules found in high abundance are universal biosignatures and demonstrate the first intrinsic experimentally tractable measure of molecular complexity, called the molecular assembly index (MA). To do this we calculate the complexity of several million molecules and validate that their complexity can be experimentally determined by mass spectrometry. This approach allows us to identify molecular biosignatures from a set of diverse samples from around the world, outer space, and the laboratory, demonstrating it is possible to build a life detection experiment based on MA that could be deployed to extraterrestrial locations, and used as a complexity scale to quantify constraints needed to direct prebiotically plausible processes in the laboratory. Such an approach is vital for finding life elsewhere in the universe or creating de-novo life in the lab.


Assuntos
Exobiologia/métodos , Espectrometria de Massas/métodos , Técnicas de Diagnóstico Molecular/métodos , Algoritmos , Quimioinformática/métodos , Biologia Computacional , Meio Ambiente Extraterreno/química , Planetas
19.
Life (Basel) ; 11(6)2021 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-34072344

RESUMO

In the search for life beyond Earth, distinguishing the living from the non-living is paramount. However, this distinction is often elusive, as the origin of life is likely a stepwise evolutionary process, not a singular event. Regardless of the favored origin of life model, an inherent "grayness" blurs the theorized threshold defining life. Here, we explore the ambiguities between the biotic and the abiotic at the origin of life. The role of grayness extends into later transitions as well. By recognizing the limitations posed by grayness, life detection researchers will be better able to develop methods sensitive to prebiotic chemical systems and life with alternative biochemistries.

20.
Dev Med Child Neurol ; 52(1): 93-8, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19583745

RESUMO

AIM: This study aimed to determine the prevalence of hip displacement and spinal deformity in a clinic population of females with Rett syndrome to define implications for screening and management. METHOD: Age, MECP2 gene status, gross motor function, prevalence of hip displacement, as measured by migration percentage, and spinal deformity, determined by measurement of Cobb angle, were recorded. RESULTS: Thirty-one females with a mean age of 15 years 6 months (SD 5y 4mo) fulfilled a clinical diagnosis of Rett syndrome. Fifteen (48%, 95% confidence interval [CI] 30-67) of the cohort had a hip migration percentage of 30% of more. Eight of the 31 patients (95% CI 12-45) had undergone surgery for the prevention or treatment of hip displacement or dislocation. Twenty-seven of the 31 patients (95% CI 70-96) had a scoliosis, with a Cobb angle of less than 10 degrees; 20 patients (95% CI 45-81) had a Cobb angle greater than 30 degrees. Eleven (95% CI 19-55) patients have required spinal fusion surgery. INTERPRETATION: The prevalence of hip displacement and spinal deformity in a clinic cohort of females with Rett syndrome in Victoria, Australia, was very high. Early, repeated, and consistent clinical and radiological surveillance for hip displacement and spinal deformities is recommended in all young patients with Rett syndrome.


Assuntos
Luxação Congênita de Quadril/diagnóstico , Programas de Rastreamento , Síndrome de Rett/diagnóstico , Escoliose/diagnóstico , Adolescente , Criança , Estudos de Coortes , Estudos Transversais , Avaliação da Deficiência , Feminino , Luxação Congênita de Quadril/epidemiologia , Luxação Congênita de Quadril/cirurgia , Humanos , Limitação da Mobilidade , Complicações Pós-Operatórias/diagnóstico , Estudos Retrospectivos , Síndrome de Rett/epidemiologia , Síndrome de Rett/cirurgia , Escoliose/epidemiologia , Escoliose/cirurgia , Fusão Vertebral
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