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1.
Acta Orthop Belg ; 89(1): 65-69, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37294987

RESUMO

Tenosynovial Giant Cell Tumor (TSGCT) or formerly pigmented villonodular synovitis (PVNS) is a rare nonmalignant tumor of the synovia seldom affecting the hip. MRI and surgical resection are the gold standards in its diagnosis and treatment. However, the accuracy of MRI is unknown, and only few reports on its surgical treatment results exist. The goal of the study was to investigate the MRI accuracy, results after surgical treatment, and natural history of untreated MRI-diagnosed hip TSGCT. Twenty-four consecutive patients with suspected TSGCT on hip MRI, between December 2006 and January 2018, were identified from our medical database. Six refused to participate. About 18 patients with a minimal follow-up of 18 months were enrolled. Charts were reviewed for histopathology results, specific treatment and recurrence. At the last follow-up, all patients had a clinical (Harris Hip Score [HHS]) and radiological examination (x-ray and MRI). Out of 18 patients with suspected TSGCT on MRI, with a mean age of 35y (range 17-52), 14 had surgi- cal resection and 4 refused surgery 1 of whom had a CT-guided biopsy. Out of 15 cases with biopsies, in 10 TSGCT was confirmed. Three surgically-treated patients showed recurrence on MRI after 24, 31 and 43 months. Two non-treated patients showed progression after 18 and 116 months. At the last follow-up (65 m; range 18-159), the mean HHS with or without recurrence was 90 and 80pts (ns). Operative vs. non-operative treatment showed HHS of 86 and 90pts (ns). In the conservatively-treated group, HHS with and without progression was 98 and 82pts (ns), respectively. MRI-suspected TSGCT of the hip was confirmed with biopsy in two-thirds of the cases. Surgical treatment showed recurrence in more than one-third of the patients. Two out of four untreated patients showed progression of the TSGCT-suspected lesion.


Assuntos
Tumor de Células Gigantes de Bainha Tendinosa , Sinovite Pigmentada Vilonodular , Humanos , Adulto , Tumor de Células Gigantes de Bainha Tendinosa/diagnóstico por imagem , Tumor de Células Gigantes de Bainha Tendinosa/cirurgia , Sinovite Pigmentada Vilonodular/diagnóstico por imagem , Sinovite Pigmentada Vilonodular/cirurgia , Biópsia , Resultado do Tratamento , Imageamento por Ressonância Magnética
2.
Geophys Res Lett ; 49(23): e2022GL099211, 2022 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-37034393

RESUMO

During the Juno Mission's encounter with Ganymede on 7 June 2021, the Juno camera (JunoCam) acquired four images of Ganymede in color. These images covered one-sixth of Ganymede at scales from 840 m to ∼4 km/pixel. Most of this area was only previously imaged by Voyager 1 in 1979, at lower spatial resolution and poorer image quality. No changes were observed over this area of Ganymede in the 42 years since Voyager. JunoCam provided overlapping coverage, from which we developed a digital elevation model of the best-resolved area. A 3 km high dome at the subjovian point was confirmed, 450 km by 750 km. We used the JunoCam images to refine the geologic map of Ganymede in eastern Perrine Regio.

3.
Nature ; 540(7631): 94-96, 2016 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-27851735

RESUMO

The deep nitrogen-covered basin on Pluto, informally named Sputnik Planitia, is located very close to the longitude of Pluto's tidal axis and may be an impact feature, by analogy with other large basins in the Solar System. Reorientation of Sputnik Planitia arising from tidal and rotational torques can explain the basin's present-day location, but requires the feature to be a positive gravity anomaly, despite its negative topography. Here we argue that if Sputnik Planitia did indeed form as a result of an impact and if Pluto possesses a subsurface ocean, the required positive gravity anomaly would naturally result because of shell thinning and ocean uplift, followed by later modest nitrogen deposition. Without a subsurface ocean, a positive gravity anomaly requires an implausibly thick nitrogen layer (exceeding 40 kilometres). To prolong the lifetime of such a subsurface ocean to the present day and to maintain ocean uplift, a rigid, conductive water-ice shell is required. Because nitrogen deposition is latitude-dependent, nitrogen loading and reorientation may have exhibited complex feedbacks.

4.
Nature ; 536(7614): 54-7, 2016 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-27362221

RESUMO

The typically dark surface of the dwarf planet Ceres is punctuated by areas of much higher albedo, most prominently in the Occator crater. These small bright areas have been tentatively interpreted as containing a large amount of hydrated magnesium sulfate, in contrast to the average surface, which is a mixture of low-albedo materials and magnesium phyllosilicates, ammoniated phyllosilicates and carbonates. Here we report high spatial and spectral resolution near-infrared observations of the bright areas in the Occator crater on Ceres. Spectra of these bright areas are consistent with a large amount of sodium carbonate, constituting the most concentrated known extraterrestrial occurrence of carbonate on kilometre-wide scales in the Solar System. The carbonates are mixed with a dark component and small amounts of phyllosilicates, as well as ammonium carbonate or ammonium chloride. Some of these compounds have also been detected in the plume of Saturn's sixth-largest moon Enceladus. The compounds are endogenous and we propose that they are the solid residue of crystallization of brines and entrained altered solids that reached the surface from below. The heat source may have been transient (triggered by impact heating). Alternatively, internal temperatures may be above the eutectic temperature of subsurface brines, in which case fluids may exist at depth on Ceres today.

5.
Nature ; 539(7627): 65-68, 2016 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-27626378

RESUMO

A unique feature of Pluto's large satellite Charon is its dark red northern polar cap. Similar colours on Pluto's surface have been attributed to tholin-like organic macromolecules produced by energetic radiation processing of hydrocarbons. The polar location on Charon implicates the temperature extremes that result from Charon's high obliquity and long seasons in the production of this material. The escape of Pluto's atmosphere provides a potential feedstock for a complex chemistry. Gas from Pluto that is transiently cold-trapped and processed at Charon's winter pole was proposed as an explanation for the dark coloration on the basis of an image of Charon's northern hemisphere, but not modelled quantitatively. Here we report images of the southern hemisphere illuminated by Pluto-shine and also images taken during the approach phase that show the northern polar cap over a range of longitudes. We model the surface thermal environment on Charon and the supply and temporary cold-trapping of material escaping from Pluto, as well as the photolytic processing of this material into more complex and less volatile molecules while cold-trapped. The model results are consistent with the proposed mechanism for producing the observed colour pattern on Charon.

6.
Foot Ankle Surg ; 28(7): 979-985, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35177329

RESUMO

BACKGROUND: This biomechanical study aimed to test if the fixation of the posterior malleolus (PM) only with screws inserted from posterior to anterior (PA) restores stability comparable with the natural condition. The extent of stability was also compared with that of anterior to posterior (AP) screw osteosynthesis (OS) with an additional syndesmotic screw (SS). METHODS: First, the stability of the upper ankle joint in seven pairs of intact lower legs were examined. Subsequently, half of the lower legs were treated with PA screw fixation of a PM fracture without SS and the other half with AP screw fixation with additional tricortical SS. RESULTS: PA OS without SS showed significantly more diastasis (p = 0.027). The AP OS with an SS revealed a diastasis that was comparable with the intact condition (p = 0.797). The use of SS led to significantly higher stability compared to OS without SS (p = 0.019). CONCLUSIONS: The Fixation of the PM alone without an additional syndesmotic screw cannot achieve intact upper ankle stability. Fixation of a PM fracture with an SS helps in nearly achieving the natural condition.


Assuntos
Fraturas do Tornozelo , Traumatismos do Tornozelo , Instabilidade Articular , Fraturas do Tornozelo/diagnóstico por imagem , Fraturas do Tornozelo/cirurgia , Traumatismos do Tornozelo/diagnóstico por imagem , Traumatismos do Tornozelo/cirurgia , Articulação do Tornozelo/cirurgia , Parafusos Ósseos , Fixação Interna de Fraturas , Humanos , Instabilidade Articular/etiologia , Instabilidade Articular/cirurgia , Amplitude de Movimento Articular , Resultado do Tratamento
7.
Nature ; 528(7581): 237-40, 2015 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-26659183

RESUMO

The dwarf planet (1) Ceres, the largest object in the main asteroid belt with a mean diameter of about 950 kilometres, is located at a mean distance from the Sun of about 2.8 astronomical units (one astronomical unit is the Earth-Sun distance). Thermal evolution models suggest that it is a differentiated body with potential geological activity. Unlike on the icy satellites of Jupiter and Saturn, where tidal forces are responsible for spewing briny water into space, no tidal forces are acting on Ceres. In the absence of such forces, most objects in the main asteroid belt are expected to be geologically inert. The recent discovery of water vapour absorption near Ceres and previous detection of bound water and OH near and on Ceres (refs 5-7) have raised interest in the possible presence of surface ice. Here we report the presence of localized bright areas on Ceres from an orbiting imager. These unusual areas are consistent with hydrated magnesium sulfates mixed with dark background material, although other compositions are possible. Of particular interest is a bright pit on the floor of crater Occator that exhibits probable sublimation of water ice, producing haze clouds inside the crater that appear and disappear with a diurnal rhythm. Slow-moving condensed-ice or dust particles may explain this haze. We conclude that Ceres must have accreted material from beyond the 'snow line', which is the distance from the Sun at which water molecules condense.

8.
Pneumologie ; 74(12): 813-841, 2020 Dec.
Artigo em Alemão | MEDLINE | ID: mdl-33291162

RESUMO

Long-term oxygen therapy is of great importance both for reducing mortality and for improving performance in patients with chronic lung diseases. The prerequisites for Long-term oxygen therapy are adequate diagnostics and clearly defined indication. A causal distinction into chronic hypoxaemic and hypercapnic respiratory failure is reasonable, from which the differential indication for non-invasive ventilation results.The revised guideline covers the diagnostics and indication of chronic lung and heart diseases, the role of oxygen in terminal illness and gives a detailed description of available oxygen devices. The guideline is intended to help avoid undersupply, oversupply and false prescriptions. Furthermore, the chapter "Postacute Oxygen Therapy" discusses the procedure, relevant in everyday life, but not yet clearly defined, for prescribing oxygen therapy for the home at the end of an inpatient stay. Another important point, the correct prescription of mobile oxygen systems, is also presented in the guideline. This document is a revised version of the guideline for longterm oxygen therapy and replaces the version of 2008.


Assuntos
Pneumopatias , Ventilação não Invasiva , Oxigenoterapia/normas , Guias de Prática Clínica como Assunto , Doença Pulmonar Obstrutiva Crônica/terapia , Insuficiência Respiratória , Sociedades Médicas/normas , Alemanha , Humanos , Oxigenoterapia/métodos , Insuficiência Respiratória/diagnóstico , Insuficiência Respiratória/terapia , Fatores de Tempo
9.
Geophys Res Lett ; 44(13): 6570-6578, 2017 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-28989206

RESUMO

Prior to the arrival of the Dawn spacecraft at Ceres, the dwarf planet was anticipated to be ice-rich. Searches for morphological features related to ice have been ongoing during Dawn's mission at Ceres. Here we report the identification of pitted terrains associated with fresh Cerean impact craters. The Cerean pitted terrains exhibit strong morphological similarities to pitted materials previously identified on Mars (where ice is implicated in pit development) and Vesta (where the presence of ice is debated). We employ numerical models to investigate the formation of pitted materials on Ceres and discuss the relative importance of water ice and other volatiles in pit development there. We conclude that water ice likely plays an important role in pit development on Ceres. Similar pitted terrains may be common in the asteroid belt and may be of interest to future missions motivated by both astrobiology and in situ resource utilization.

10.
Nature ; 479(7374): 502-5, 2011 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-22089135

RESUMO

Europa, the innermost icy satellite of Jupiter, has a tortured young surface and sustains a liquid water ocean below an ice shell of highly debated thickness. Quasi-circular areas of ice disruption called chaos terrains are unique to Europa, and both their formation and the ice-shell thickness depend on Europa's thermal state. No model so far has been able to explain why features such as Conamara Chaos stand above surrounding terrain and contain matrix domes. Melt-through of a thin (few-kilometre) shell is thermodynamically improbable and cannot raise the ice. The buoyancy of material rising as either plumes of warm, pure ice called diapirs or convective cells in a thick (>10 kilometres) shell is insufficient to produce the observed chaos heights, and no single plume can create matrix domes. Here we report an analysis of archival data from Europa, guided by processes observed within Earth's subglacial volcanoes and ice shelves. The data suggest that chaos terrains form above liquid water lenses perched within the ice shell as shallow as 3 kilometres. Our results suggest that ice-water interactions and freeze-out give rise to the diverse morphologies and topography of chaos terrains. The sunken topography of Thera Macula indicates that Europa is actively resurfacing over a lens comparable in volume to the Great Lakes in North America.

11.
Unfallchirurg ; 120(5): 432-436, 2017 May.
Artigo em Alemão | MEDLINE | ID: mdl-28083631

RESUMO

We report a difficult healing process after a femoral shaft fracture in childhood. We present surgical correction options of femoral shortening due to pseudarthrosis after elastic stable intramedullary nailing. First, we tried to establish distraction using an external fixator, followed by plate osteosynthesis. After material failure of plate osteosynthesis, we treated the refracture with intramedullary nailing, after which bone healing occurred.


Assuntos
Alongamento Ósseo/métodos , Terapia Combinada/métodos , Fraturas do Fêmur/complicações , Fraturas do Fêmur/terapia , Fixação Interna de Fraturas/métodos , Desigualdade de Membros Inferiores/etiologia , Desigualdade de Membros Inferiores/terapia , Adolescente , Criança , Feminino , Fraturas do Fêmur/diagnóstico por imagem , Humanos , Desigualdade de Membros Inferiores/diagnóstico por imagem , Resultado do Tratamento , Adulto Jovem
12.
Br J Cancer ; 110(4): 984-90, 2014 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-24434429

RESUMO

BACKGROUND: To investigate the clinical utility of pretreatment plasma fibrinogen levels in malignant pleural mesothelioma (MPM) patients. METHODS: A retrospective multicenter study was performed in histologically proven MPM patients. All fibrinogen levels were measured at the time of diagnosis and clinical data were retrospectively collected after approval of the corresponding ethics committees. RESULTS: In total, 176 MPM patients (mean age: 63.5 years ± 10.4 years, 38 females and 138 males) were analysed. Most patients (n=154, 87.5%) had elevated (≥ 390 mg dl(-1)) plasma fibrinogen levels. When patients were grouped by median fibrinogen, patients with low level (≤ 627 mg dl(-1)) had significantly longer overall survival (OS) (19.1 months, confidence interval (CI) 14.5-23.7 months) when compared with those with high level (OS 8.5; CI 6.2-10.7 months). In multivariate survival analyses, fibrinogen was found to be an independent prognostic factor (hazard ratio 1.81, CI 1.23-2.65). Most interestingly, fibrinogen (cutoff 75th percentile per 750 mg dl(-1)) proved to be a predictive biomarker indicating treatment benefit achieved by surgery within multimodality therapy (interaction term: P=0.034). Accordingly, only patients below the 75th percentile benefit from surgery within multimodality therapy (31.3 vs 5.3 months OS). CONCLUSIONS: Fibrinogen is a novel independent prognostic biomarker in MPM. Most importantly, fibrinogen predicted treatment benefit achieved by surgery within multimodality therapy.


Assuntos
Biomarcadores Tumorais/sangue , Fibrinogênio/análise , Neoplasias Pulmonares/sangue , Neoplasias Pulmonares/cirurgia , Mesotelioma/sangue , Mesotelioma/cirurgia , Terapia Combinada , Feminino , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Masculino , Mesotelioma/tratamento farmacológico , Mesotelioma Maligno , Pessoa de Meia-Idade , Neoplasias Pleurais/sangue , Neoplasias Pleurais/tratamento farmacológico , Neoplasias Pleurais/cirurgia , Prognóstico , Estudos Retrospectivos
13.
J Anat ; 223(1): 61-8, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23678961

RESUMO

In the last decade, diffusion tensor imaging (DTI) has been used increasingly to investigate three-dimensional (3D) muscle architectures. So far there is no study that has proved the validity of this method to determine fascicle lengths and pennation angles within a whole muscle. To verify the DTI method, fascicle lengths of m. soleus as well as their pennation angles have been measured using two different methods. First, the 3D muscle architecture was analyzed in vivo applying the DTI method with subsequent deterministic fiber tractography. In a second step, the muscle architecture of the same muscle was analyzed using a standard manual digitization system (MicroScribe MLX). Comparing both methods, we found differences for the median pennation angles (P < 0.001) but not for the median fascicle lengths (P = 0.216). Despite the statistical results, we conclude that the DTI method is appropriate to determine the global fiber orientation. The difference in median pennation angles determined with both methods is only about 1.2° (median pennation angle of MicroScribe: 9.7°; DTI: 8.5°) and probably has no practical relevance for muscle simulation studies. Determining fascicle lengths requires additional restriction and further development of the DTI method.


Assuntos
Imagem de Tensor de Difusão/métodos , Músculo Esquelético/anatomia & histologia , Animais , Membro Posterior/anatomia & histologia , Imageamento Tridimensional , Fibras Musculares Esqueléticas , Coelhos , Reprodutibilidade dos Testes
14.
Global Spine J ; : 21925682231192847, 2023 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-37549640

RESUMO

STUDY DESIGN: Multicenter prospective cohort study. OBJECTIVES: Anxiety in combination with osteoporotic vertebral compression fractures (OVCFs) of the spine remains understudied. The purpose of this study was to analyze whether anxiety has an impact on the short-term functional outcome of patients with an OVCF. Furthermore, a direct impact of the fracture on the patient's anxiety during hospitalization should be recognized. METHODS: All inpatients with an OVCF of the thoracolumbar spine from 2017 to 2020 were included. Trauma mechanism, analgetic medication, anti-osteoporotic therapy, timed-up-and-go test (TuG), mobility, Barthel index, Oswestry-Disability Index (ODI) and EQ5D-5L were documented.For statistical analysis, the U test, chi-square independence test, Spearman correlation, General Linear Model for repeated measures, Bonferroni analysis and Wilcoxon test were used. The item anxiety/depression of the EQ5D-5L was analyzed to describe the patients' anxiousness. RESULTS: Data from 518 patients from 17 different hospitals were evaluated. Fracture severity showed a significant correlation (r = .087, P = .0496) with anxiety. During the hospital stay, pain medication (P < .001), anti-osteoporotic medication (P < .001), and initiation of surgical therapy (P < .001) were associated with less anxiety. The anxiety of a patient at discharge was negatively related to the functional outcomes at the individual follow-up: TuG (P < .001), Barthel index (P < .001), ODI (P < .001) and EQ5D-5L (P < .001). CONCLUSIONS: Higher anxiety is associated with lower functional outcome after OVCF. The item anxiety/depression of the EQ5D-5L provides an easily accessible, quick and simple tool that can be used to screen for poor outcomes and may also offer the opportunity for a specific anxiety intervention.

15.
Eur J Trauma Emerg Surg ; 48(3): 2297-2307, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34357408

RESUMO

PURPOSE: Posterior multilevel fixation of traumatic instability in ankylosing spinal disease (ASD) can be performed by open surgery (OS) or minimally invasive surgery (MIS). We investigated whether both methods differ based on the reduction results and perioperative parameters. METHODS: In this retrospective cohort study, OS and MIS groups were investigated. The bisegmental Cobb angles and dislocation angles were measured using pre- and postoperative CT images, and the initial malalignment and achieved reduction were calculated. Cut-seam time, calculated blood loss, transfusion number, fluoroscopy time, pedicle screw placement accuracy, duration of ICU stay, in-patient stay, and complications (bleeding, postoperative thrombosis and embolism, and postoperative mortality) were recorded. RESULTS: Seventy-five ASD patients with spine fractures (Ø 75 ± 11 years, male: 52, female: 23) (MIS: 48; OS: 27) were included in this study. The extent of reduction did not differ in the OS and MIS groups (p = 0.465; MIS:- 1 ± 3°, OS:-2 ± 6°). The residual postoperative malalignment angle was not significantly different (p = 0.283). Seventy-eight of the implanted screws (11%) showed malpositioning. No difference was found between OS and MIS (MIS, 37 [7%]; OS, 41 [16%]; p = 0.095). MIS was associated with less blood loss (OS: 1.28 ± 0.78 l, MIS: 0.71 ± 0.57 l, p = 0.001), cut-seam time (MIS: 98 ± 44 min, OS: 166 ± 69 min, p < 0.001), and hospital stay (MIS: Ø14 ± 16 d, OS: Ø38 ± 49 d, p = 0.02) than OS. CONCLUSION: OS and MIS show equally limited performance in terms of the fracture reduction achieved. The MIS technique was superior to OS based on the perioperative outcome. Therefore, MIS should be preferred over OS for unstable spinal injuries, excluding C-type fractures, in ASD patients without neurological impairment.


Assuntos
Parafusos Pediculares , Doenças da Coluna Vertebral , Fraturas da Coluna Vertebral , Fusão Vertebral , Feminino , Humanos , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/cirurgia , Masculino , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Estudos Retrospectivos , Fraturas da Coluna Vertebral/diagnóstico por imagem , Fraturas da Coluna Vertebral/cirurgia , Fusão Vertebral/métodos , Resultado do Tratamento
16.
Pharmacogenomics J ; 10(3): 219-25, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19884907

RESUMO

CYP2C19 converts the tricyclic antidepressant imipramine to its active metabolite desipramine, which is subsequently inactivated by CYP2D6. The novel CYP2C19*17 allele causes ultrarapid metabolism of CYP2C19 substrates. We genotyped 178 depressed patients on imipramine for CYP2C19*17, and measured steady-state imipramine and desipramine plasma concentrations. Mean dose-corrected imipramine plasma concentration was significantly dependent on CYP2C19 genotype (Kruskal-Wallis test, P=0.01), with circa 30% lower levels in CYP2C19*17/*17 individuals compared with CYP2C19*1/*1 (wild-type) patients. The mean dose-corrected imipramine+desipramine plasma concentrations and imipramine/desipramine ratios were not significantly different between genotype subgroups (Kruskal-Wallis tests, P>or=0.12). In a multivariate analysis, we found a significant, but limited effect (P=0.035, eta(2)=0.031) of the CYP2C19*17 genotype on imipramine+desipramine concentrations. Although the CYP2C19*17 allele is associated with a significantly increased metabolism of imipramine, CYP2C19*17 genotyping will, in our view, not importantly contribute to dose management of patients on imipramine therapy guided by imipramine+desipramine plasma concentrations.


Assuntos
Antidepressivos Tricíclicos/sangue , Hidrocarboneto de Aril Hidroxilases/genética , Depressão/tratamento farmacológico , Imipramina/sangue , Adulto , Antidepressivos Tricíclicos/uso terapêutico , Citocromo P-450 CYP2C19 , Depressão/genética , Desipramina/sangue , Genótipo , Humanos , Imipramina/uso terapêutico , Pessoa de Meia-Idade , Análise Multivariada
17.
Nat Commun ; 11(1): 3679, 2020 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-32778649

RESUMO

Hydrothermal processes in impact environments on water-rich bodies such as Mars and Earth are relevant to the origins of life. Dawn mapping of dwarf planet (1) Ceres has identified similar deposits within Occator crater. Here we show using Dawn high-resolution stereo imaging and topography that Ceres' unique composition has resulted in widespread mantling by solidified water- and salt-rich mud-like impact melts with scattered endogenic pits, troughs, and bright mounds indicative of outgassing of volatiles and periglacial-style activity during solidification. These features are distinct from and less extensive than on Mars, indicating that Occator melts may be less gas-rich or volatiles partially inhibited from reaching the surface. Bright salts at Vinalia Faculae form thin surficial precipitates sourced from hydrothermal brine effusion at many individual sites, coalescing in several larger centers, but their ages are statistically indistinguishable from floor materials, allowing for but not requiring migration of brines from deep crustal source(s).

18.
Nat Commun ; 11(1): 3680, 2020 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-32778642

RESUMO

Before acquiring highest-resolution data of Ceres, questions remained about the emplacement mechanism and source of Occator crater's bright faculae. Here we report that brine effusion emplaced the faculae in a brine-limited, impact-induced hydrothermal system. Impact-derived fracturing enabled brines to reach the surface. The central faculae, Cerealia and Pasola Facula, postdate the central pit, and were primarily sourced from an impact-induced melt chamber, with some contribution from a deeper, pre-existing brine reservoir. Vinalia Faculae, in the crater floor, were sourced from the laterally extensive deep reservoir only. Vinalia Faculae are comparatively thinner and display greater ballistic emplacement than the central faculae because the deep reservoir brines took a longer path to the surface and contained more gas than the shallower impact-induced melt chamber brines. Impact-derived fractures providing conduits, and mixing of impact-induced melt with deeper endogenic brines, could also allow oceanic material to reach the surfaces of other large icy bodies.

19.
Wien Klin Mag ; 23(3): 92-115, 2020.
Artigo em Alemão | MEDLINE | ID: mdl-32427192

RESUMO

The COVID-19 pandemic is currently a challenge worldwide. In Austria, a crisis within the health care system has so far been avoided. The treatment of patients with community-acquired pneumonia (CAP), including SARS-CoV­2 infections, should continue to be based on evidence-based CAP guidelines during the pandemic. However, COVID-19-specific adjustments are useful. The treatment of patients with chronic lung diseases must be adapted during the pandemic, but must still be guaranteed.

20.
Science ; 367(6481)2020 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-32054693

RESUMO

The outer Solar System object (486958) Arrokoth (provisional designation 2014 MU69) has been largely undisturbed since its formation. We studied its surface composition using data collected by the New Horizons spacecraft. Methanol ice is present along with organic material, which may have formed through irradiation of simple molecules. Water ice was not detected. This composition indicates hydrogenation of carbon monoxide-rich ice and/or energetic processing of methane condensed on water ice grains in the cold, outer edge of the early Solar System. There are only small regional variations in color and spectra across the surface, which suggests that Arrokoth formed from a homogeneous or well-mixed reservoir of solids. Microwave thermal emission from the winter night side is consistent with a mean brightness temperature of 29 ± 5 kelvin.

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