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1.
J Clin Med ; 13(11)2024 May 26.
Artículo en Inglés | MEDLINE | ID: mdl-38892834

RESUMEN

Introduction: Although stentrievers (SRs) have been a mainstay of mechanical thrombectomy (MT), and current guidelines recommend the use of SRs in the treatment of large vessel occlusion stroke (LVO), there is a paucity of studies in the literature comparing SRs directly against each other in terms of mechanical and functional properties. Timely access to endovascular therapy and the ability to restore intracranial flow in a safe, efficient, and efficacious manner have been critical to the success of MT. This study aimed to investigate the impact of contemporary SR characteristics, including model, brand, size, and length, on the first-pass effect (FPE) in patients with acute ischemic stroke. Methods: Consecutive patients with M1 occlusion treated with a single SR+BGC were recruited from the ROSSETTI registry. The primary outcome was the FPE that was defined as modified (mFPE) or true (tFPE) for the achievement of modified thrombolysis in cerebral infarction (mTICI) grades 2b-3 or 3 after a single device pass, respectively. We compared patients who achieved mFPE with those who achieved tFPE according to SR characteristics. Results: We included 610 patients (52.3% female and 47.7% male, mean age 75.1 ± 13.62 years). mFPE was achieved in 357 patients (58.5%), whereas tFPE was achieved in 264 (43.3%). There was no significant association between SR characteristics and mFPE or tFPE. Specifically, the SR size did not show a statistically significant relationship with improvement in FPE. Similarly, the length of the SR did not yield significant differences in the mFPE and tFPE, even when the data were grouped. Conclusions: Our data indicate that contemporary SR-mediated thrombectomy characteristics, including model, brand, size, and length, do not significantly affect the FPE.

2.
Chemosphere ; 357: 142127, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38663678

RESUMEN

Water treatment technologies need to go beyond the current control of organic contaminants and ensure access to potable water. However, existing methods are still costly and often inadequate. In this context, novel catalysts that improve the mineralization degree of a wider range of pharmaceuticals through more benign and less consuming methodologies are highly sought after. ZnO, especially when doped, is a well-known semiconductor that also excels in the photocatalytic removal of persistent organic pollutants. In this study, we investigated the effect of doping ZnO nanoparticles with either copper, gallium or indium on the structure, morphology, photophysical properties and photocatalytic mineralization of pharmaceuticals. Their architecture was further improved through the fabrication of composites, pairing the best performing doped ZnO with either BaFe12O19 or nickel nanoparticles. Their suitability was tested on a complex 60-ppm multi-pollutant solution (tetracycline, levofloxacin and lansoprazole). The activation strategy combined photocatalysis with peroxymonosulfate (PMS) as an environmentally friendly source of highly oxidative sulfate radicals. The alliance of doped ZnO and BaFe12O19 was particularly successful, resulting in magnetic microcroquette-shaped composites with excellent inter-component synergy. In fact, indium outperformed the other proposed metal dopants, exceeding 97% mineralization after 1 h and achieving complete elimination after 3 h. All composites excelled in terms of reusability, with no catalytic loss after 10 consecutive cycles and minimal leakage of metal ions, highlighting their applicability in water remediation.


Asunto(s)
Contaminantes Químicos del Agua , Óxido de Zinc , Óxido de Zinc/química , Contaminantes Químicos del Agua/química , Catálisis , Purificación del Agua/métodos , Luz , Cobre/química , Preparaciones Farmacéuticas/química , Indio/química , Peróxidos
3.
Chemosphere ; 354: 141656, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38467197

RESUMEN

The rampant upsurge of organic pollutants in aqueous media has become one of the major concerns nowadays. Finding non-specific catalysts that can target a wide range of organic pollutants is a key challenge. Eco-friendly oxidative radicals, such as promoted by peroxymonosulfate (PMS), are necessary for efficient water decontamination. We propose a multicomponent composite catalyst for activating PMS using a dual strategy of sonophotocatalysis. The composite integrates cobalt ferrite and Cu- or Ce-doped SnO2, with the at. % of doping metal and the mixture ratio carefully balanced. The top-performing architectures were able to decompose rhodamine B (20 ppm), a representative pollutant, in under 3 min and achieve over 70% mineralization in just 5 min. The synthesized nanocomposites demonstrated exceptional sonophotocatalytic performance, even when treating complex and diverse multipollutant solutions (80 ppm), achieving over 75% mineralization after 150 min. Considering their high stability and reusability, the proposed CoFe2O4/Cu- and Ce-doped SnO2 materials are among the state-of-the-art heterogeneous catalysts for mineralizing organic pollutants through PMS activation.


Asunto(s)
Contaminantes Ambientales , Contaminantes Químicos del Agua , Peróxidos , Metales
4.
Trials ; 25(1): 35, 2024 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-38195586

RESUMEN

RATIONALE: In-stent reocclusion after endovascular therapy has a negative impact on outcomes in acute ischemic stroke (AIS) due to tandem lesions (TL). Optimal antiplatelet therapy approach in these patients to avoid in-stent reocclusion is yet to be elucidated. AIMS: To assess efficacy and safety of intravenous tirofiban versus intravenous aspirin in patients undergoing MT plus carotid stenting in the setting of AIS due to TL. SAMPLE SIZE ESTIMATES: Two hundred forty patients will be enrolled, 120 in every treatment arm. METHODS AND DESIGN: A multicenter, prospective, randomized, controlled (aspirin group), assessor-blinded clinical trial will be conducted. Patients fulfilling the inclusion criteria will be randomized at MT onset to the experimental or control group (1:1). Intravenous aspirin will be administered at a 500-mg single dose and tirofiban at a 500-mcg bolus followed by a 200-mcg/h infusion during the first 24 h. All patients will be followed for up to 3 months. STUDY OUTCOMES: Primary efficacy outcome will be the proportion of patients with carotid in-stent thrombosis within the first 24 h after MT. Primary safety outcome will be the rate of symptomatic intracranial hemorrhage. DISCUSSION: This will be the first clinical trial to assess the best antiplatelet therapy to avoid in-stent thrombosis after MT in patients with TL. TRIAL REGISTRATION: The trial is registered as NCT05225961. February, 7th, 2022.


Asunto(s)
Aspirina , Accidente Cerebrovascular Isquémico , Trombosis , Tirofibán , Humanos , Aspirina/efectos adversos , Aspirina/uso terapéutico , Inhibidores de Agregación Plaquetaria/efectos adversos , Inhibidores de Agregación Plaquetaria/uso terapéutico , Estudios Prospectivos , Tirofibán/efectos adversos , Tirofibán/uso terapéutico , Ensayos Clínicos Controlados Aleatorios como Asunto , Estudios Multicéntricos como Asunto
5.
J Perinat Med ; 52(2): 181-185, 2024 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-38114463

RESUMEN

OBJECTIVES: Pulmonary embolism (PE) is an important cause of maternal mortality. There are several guidelines for its diagnosis and management, but there is little information regarding follow-up and frequency of long-term complications. The aim of the study was to determine the frequency of long-term cardiovascular symptoms in patients who had obstetric PE. METHODS: Cross-sectional study including patients who had PE during pregnancy or the puerperium. A telephone interview was conducted at least one year after PE, to determine the frequency of cardiovascular symptoms, general health, and COVID-19 infection, considering the study was conducted during the 2020 pandemic. RESULTS: In five years (2015-2019) there were eleven patients with PE, two died during the acute phase, and the rest (nine) were alive and able to answer our interview. Cardiovascular symptoms were common (6, 67 %), the most frequent were fatigue, edema, and mild dyspnea. Four patients (44 %) had slight limitation of physical activity and one (11 %) had PE recurrence. Of the six symptomatic patients four had obesity and one was overweight. CONCLUSIONS: There is a high frequency of long-term cardiovascular symptoms in patients who had PE during pregnancy or the puerperium. Stronger evidence is needed to design a long-term care pathway after obstetric PE.


Asunto(s)
Embolia Pulmonar , Humanos , Embarazo , Femenino , Estudios Transversales , México/epidemiología , Embolia Pulmonar/diagnóstico , Embolia Pulmonar/epidemiología , Embolia Pulmonar/terapia
6.
SAGE Open Nurs ; 9: 23779608231196843, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37675150

RESUMEN

Introduction: Nurses and respiratory therapists working on the frontline during the pandemic surge were short-staffed and worked extended hours while adding new tasks to already demanding workloads. As the world watched news covering COVID-19's effect, nurses and respiratory therapists lived through the daily stress of treating each patient with care, dignity, and compassion. Limited studies have focused on this population, which is vital to providing care and saving lives; research is needed to understand nurses' and respiratory therapists' experiences during the COVID-19 pandemic. Objective: The study aimed to understand nurses' and respiratory therapists' experiences during the COVID-19 pandemic. Methods: A qualitative descriptive study, informed by naturalistic philosophy, was designed to obtain a detailed account of participants' experiences during the pandemic surge. A purposive sample was recruited and enrolled from the community through professional organizations and snowball sampling from December 2021 to September 2022. Data was analyzed using thematic analysis. Results: Participants were seven registered nurses and six respiratory therapists employed full-time in an intensive care unit, step-down intensive care unit, emergency department, or medical-surgical unit; seven (53.8%) with an associate degree, and six (46.2%) with a bachelor's degree. Eight (66.7%) self-identified as White, one Asian, one non-Hispanic Black, and two Pacific Islanders. The mean age was 40, and 10 (76.9%) were female. Six primary themes emerged: (a) the work-life experience before the COVID-19 pandemic, (b) the work-life experience during the COVID-19 pandemic, (c) the personal life experience during COVID-19, (d) the coping period, (e) the professional role change, and (f) the work and personal life experiences post COVID-19 surge. Conclusion: The knowledge gained from this study can help improve understanding of the professional quality of life, the need for organizational and community support, and for healthcare professionals to seek help and practice self-care to prevent burnout and secondary traumatic stress.

7.
Molecules ; 28(11)2023 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-37298738

RESUMEN

In this study, nanocomposites based on polypropylene are synthesized by the in situ polymerization of propene in the presence of mesoporous SBA-15 silica, which acts as a carrier of the catalytic system (zirconocene as catalyst and methylaluminoxane as cocatalyst). The protocol for the immobilization and attainment of hybrid SBA-15 particles involves a pre-stage of contact between the catalyst with cocatalyst before their final functionalization. Two zirconocene catalysts are tested in order to attain materials with different microstructural characteristics, molar masses and regioregularities of chains. Some polypropylene chains are able to be accommodated within the silica mesostructure of these composites. Thus, an endothermic event of small intensity appears during heating calorimetric experiments at approximately 105 °C. The existence of these polypropylene crystals, confined within the nanometric channels of silica, is corroborated by SAXS measurements obtained via the change in the intensity and position of the first-order diffraction of SBA-15. The incorporation of silica also has a very significant effect on the rheological response of the resultant materials, leading to important variations in various magnitudes, such as the shear storage modulus, viscosity and δ angle, when a comparison is established with the corresponding neat iPP matrices. Rheological percolation is reached, thus demonstrating the role of SBA-15 particles as filler, in addition to the supporting role that they exert during the polymerizations.


Asunto(s)
Nanocompuestos , Polipropilenos , Polimerizacion , Polipropilenos/química , Metalocenos , Peso Molecular , Dispersión del Ángulo Pequeño , Difracción de Rayos X , Nanocompuestos/química , Dióxido de Silicio/química
8.
J Geophys Res Planets ; 128(1): e2022JE007480, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37034458

RESUMEN

The pressure sensors on Mars rover Perseverance measure the pressure field in the Jezero crater on regular hourly basis starting in sol 15 after landing. The present study extends up to sol 460 encompassing the range of solar longitudes from L s  âˆ¼ 13°-241° (Martian Year (MY) 36). The data show the changing daily pressure cycle, the sol-to-sol seasonal evolution of the mean pressure field driven by the CO2 sublimation and deposition cycle at the poles, the characterization of up to six components of the atmospheric tides and their relationship to dust content in the atmosphere. They also show the presence of wave disturbances with periods 2-5 sols, exploring their baroclinic nature, short period oscillations (mainly at night-time) in the range 8-24 min that we interpret as internal gravity waves, transient pressure drops with duration ∼1-150 s produced by vortices, and rapid turbulent fluctuations. We also analyze the effects on pressure measurements produced by a regional dust storm over Jezero at L s  âˆ¼ 155°.

9.
Eur Stroke J ; 8(1): 380-386, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-37021200

RESUMEN

Background: In-stent thrombosis after mechanical thrombectomy (MT) worsen outcomes in acute ischemic stroke (AIS) due to tandem lesions (TL). Although an optimal antiplatelet therapy is needed, the best approach to avoid in-stent thrombosis is yet to be elucidated. Hypothesis: Low-dose intravenous tirofiban is superior to intravenous aspirin in avoiding in-stent thrombosis in patients undergoing MT plus carotid stenting in the setting of AIS due to TL. Methods: The ATILA-trial is a multicenter, prospective, phase IV, randomized, controlled (aspirin group as control), assessor-blinded clinical trial. Patients fulfilling inclusion criteria (AIS due to TL, ASPECTS ⩾ 6, pre-stroke modified Rankin Scale ⩽2 and onset <24 h) will be randomized (1:1) at MT onset to experimental (intravenous tirofiban) or control group (intravenous aspirin). Intravenous aspirin will be administered at a 500 mg single dose and tirofiban at a 500 µg bolus followed by a 200 µg/h infusion during first 22 h. All patients will be followed up to 3 months. Sample size estimated is 240 patients. Outcomes: The primary efficacy outcome is the proportion of patients with carotid in-stent thrombosis within the first 24 h after MT. The primary safety outcome is the rate of symptomatic intracranial hemorrhage. Secondary outcomes include functional independence defined as modified Rankin Scale 0-2, proportion of patients undergoing rescue therapy due to in-stent aggregation during MT and carotid reocclusion at 30 days. Discussion: ATILA-trial will be the first clinical trial regarding the best antiplatelet therapy to avoid in-stent thrombosis after MT in patients with TL. Trial registration: NCT0522596.


Asunto(s)
Isquemia Encefálica , Accidente Cerebrovascular Isquémico , Trombosis , Humanos , Tirofibán/uso terapéutico , Accidente Cerebrovascular Isquémico/tratamiento farmacológico , Inhibidores de Agregación Plaquetaria/efectos adversos , Estudios Prospectivos , Isquemia Encefálica/inducido químicamente , Resultado del Tratamiento , Aspirina/efectos adversos , Trombectomía/efectos adversos , Trombosis/tratamiento farmacológico , Ensayos Clínicos Controlados Aleatorios como Asunto , Estudios Multicéntricos como Asunto , Ensayos Clínicos Fase IV como Asunto
10.
Nanomaterials (Basel) ; 13(5)2023 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-36903668

RESUMEN

Synthesizing efficient heterogeneous catalysts with multiple active sites able to activate peroxymonosulfate (PMS) for the degradation of persistent organic pollutants continues to be a challenge for societies worldwide. In response, cost-effective, eco-friendly oxidized Ni-rich and Co-rich CoNi micro-nanostructured films were fabricated following a two-step process based on simple electrodeposition using green deep eutectic solvent as an electrochemical media and thermal annealing. The CoNi-based catalysts demonstrated exceptional efficiency in the heterogeneous catalyzed activation of PMS for tetracycline degradation and mineralization. The effects of the catalysts' chemical nature and morphology, the pH, the concentration of PMS, irradiation with visible light, and the duration of contact with the catalysts on the degradation and mineralization of tetracycline were also studied. In dark conditions, oxidized Co-rich CoNi degraded more than 99% of tetracyclines in only 30 min and mineralized more than 99% of them in only 60 min. Moreover, the degradation kinetics doubled from 0.173 min-1 in dark conditions to 0.388 min-1 under visible light irradiation. In addition, the material demonstrated excellent reusability and can be easily recovered with simple heat treatment. Given those findings, our work provides new strategies for constructing high-efficiency and cost-effective PMS catalysts and elucidating the effects of operational parameters and primary reactive species formed by the catalyst-PMS system on water treatment technologies.

11.
Interv Neuroradiol ; 29(1): 102-107, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35043725

RESUMEN

INTRODUCTION: Mechanical thrombectomy for large vessel occlusion in the anterior circulation has been shown to be beneficial. The question of whether this technique is safe and effective in the distal vasculature remains unanswered. We wanted to compare outcome data from mechanical thrombectomy of M2 branches of the middle cerebral artery (MCA) with those of the M1 segment, and better understand the clinical predictors of these M2 occlusions. METHODS: A retrospective analysis was performed of data prospectively collected between January 2017 and July 2021 from patients with acute ischemic stroke undergoing mechanical thrombectomy of isolated M1 or M2 branches of the MCA. RESULTS: 350 patients were identified, 287 with M1 and 63 with M2 occlusions. Mean age was 70.71 ± 12.55 and 75.21 ± 10.21 years, respectively (p = 0.0083). Baseline Alberta Stroke Program Computed Tomography (ASPECT) score was worse in the M1 cohort (7.68 ± 1.73 vs. 8.32 ± 1.54; p = 0.0079), while there was no significant difference in National Institutes of Health Stroke Scale (NIHSS) scores. No statistical disparity existed in mean procedure duration for each cohort; fewer thrombectomy attempts were required in the M2 cohort (2.01 vs. 1.63; p = 0.0478). There was no statistical difference in total time to recanalization (559.19 vs. 629.97, p = 0.2506). Similar rates of successful reperfusion were observed (Thrombolysis in Ischaemic Stroke score [TICI] ≥ 2b 80.84% vs. 71.43% p = 0.1221). Good outcome (modified Rankin scale ≤ 2) was 56.10 in M1 occlusions and 63.49% on M2 groups. Intracranial haemorrhage rates were similar. CONCLUSIONS: M2 thrombectomy is safe and a significant proportion of patients achieve a good clinical outcome. Advanced age, atrial fibrillation and previous treatment with anticoagulants were predictors for poor outcome. Good outcome was achieved when effective recanalization was obtained.


Asunto(s)
Isquemia Encefálica , Procedimientos Endovasculares , Accidente Cerebrovascular Isquémico , Accidente Cerebrovascular , Humanos , Persona de Mediana Edad , Anciano , Anciano de 80 o más Años , Accidente Cerebrovascular/cirugía , Arteria Cerebral Media , Isquemia Encefálica/cirugía , Infarto de la Arteria Cerebral Media/cirugía , Estudios Retrospectivos , Resultado del Tratamiento , Trombectomía/métodos , Procedimientos Endovasculares/métodos
12.
Nat Commun ; 13(1): 7505, 2022 12 13.
Artículo en Inglés | MEDLINE | ID: mdl-36513637

RESUMEN

Dust devils (convective vortices loaded with dust) are common at the surface of Mars, particularly at Jezero crater, the landing site of the Perseverance rover. They are indicators of atmospheric turbulence and are an important lifting mechanism for the Martian dust cycle. Improving our understanding of dust lifting and atmospheric transport is key for accurate simulation of the dust cycle and for the prediction of dust storms, in addition to being important for future space exploration as grain impacts are implicated in the degradation of hardware on the surface of Mars. Here we describe the sound of a Martian dust devil as recorded by the SuperCam instrument on the Perseverance rover. The dust devil encounter was also simultaneously imaged by the Perseverance rover's Navigation Camera and observed by several sensors in the Mars Environmental Dynamics Analyzer instrument. Combining these unique multi-sensorial data with modelling, we show that the dust devil was around 25 m large, at least 118 m tall, and passed directly over the rover travelling at approximately 5 m s-1. Acoustic signals of grain impacts recorded during the vortex encounter provide quantitative information about the number density of particles in the vortex. The sound of a Martian dust devil was inaccessible until SuperCam microphone recordings. This chance dust devil encounter demonstrates the potential of acoustic data for resolving the rapid wind structure of the Martian atmosphere and for directly quantifying wind-blown grain fluxes on Mars.


Asunto(s)
Medio Ambiente Extraterrestre , Marte , Polvo/análisis , Viento , Atmósfera
13.
Polymers (Basel) ; 14(22)2022 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-36433179

RESUMEN

Different circular strategies attempt to increase the energy efficiency or reduce the accumulation of plastic in landfills through the development of circular polymers. Chemical recycling is essential to recover the initial monomers from plastic residues for obtaining new goods showing the same properties as those using virgin monomers from the initial feedstocks. This work addresses the preparation of poly(ethylene-co-norbornene) copolymers for a promising generation of materials for energy applications that could be treated by chemical recycling. The thermal and thermo-oxidative stability for these copolymers with norbornene is higher than for the neat PE, while their degradation exhibits an activation energy lower than that observed in PE, pointing out that chemical recycling would require a lower energy consumption.

14.
Acta Neurol Scand ; 146(5): 598-603, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35975464

RESUMEN

INTRODUCTION: Intra- or peri-procedural aneurysm rupture is one of the most feared adverse effects associated with embolization. Our aim was to report the characteristics of patients suffering intra- or peri-procedural ruptures during embolization of cerebral aneurysms. PATIENTS AND METHODS: Between March 1994 and October 2021, 648 consecutive cerebral aneurysms were treated by endovascular procedure at our facility. Medical records were reviewed retrospectively with emphasis on procedure description, potential risk factors, and clinical outcomes related to intra- or peri-procedural rupture. RESULTS: Of the 648 patients, 17 (2.6%) suffered an intra- or peri-procedural hemorrhagic event. The most common location was the anterior communicating artery. There was no significant difference between previously ruptured and unruptured aneurysms in the incidence of bleeding. In four patients, bleeding was evident within 24 h after the procedure. The clinical evolution at three months was poor and only four patients presented a positive evolution. There were 11 deaths (64.71%). Balloon remodeling was associated with an increased frequency of ruptures, while stenting was a safer treatment. CONCLUSION: Aneurysmal rupture during endovascular therapy is unpredictable, and its occurrence can be devastating. The incidence is quite low although the outcome is frequently poor. Early detection and proper management, including prompt occlusion of the aneurysm, are important to achieve a positive outcome. Anterior communicating artery aneurysms and those treated with balloon catheters have a higher incidence of rupture. A small number of ruptures of uncertain origin occur that go unnoticed in digital subtraction angiograms.


Asunto(s)
Aneurisma Roto , Embolización Terapéutica , Procedimientos Endovasculares , Aneurisma Intracraneal , Aneurisma Roto/diagnóstico por imagen , Aneurisma Roto/cirugía , Angiografía Cerebral/efectos adversos , Embolización Terapéutica/efectos adversos , Procedimientos Endovasculares/efectos adversos , Procedimientos Endovasculares/métodos , Humanos , Aneurisma Intracraneal/diagnóstico por imagen , Aneurisma Intracraneal/cirugía , Estudios Retrospectivos , Resultado del Tratamiento
15.
Sci Adv ; 8(21): eabn3783, 2022 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-35613267

RESUMEN

Despite the importance of sand and dust to Mars geomorphology, weather, and exploration, the processes that move sand and that raise dust to maintain Mars' ubiquitous dust haze and to produce dust storms have not been well quantified in situ, with missions lacking either the necessary sensors or a sufficiently active aeolian environment. Perseverance rover's novel environmental sensors and Jezero crater's dusty environment remedy this. In Perseverance's first 216 sols, four convective vortices raised dust locally, while, on average, four passed the rover daily, over 25% of which were significantly dusty ("dust devils"). More rarely, dust lifting by nonvortex wind gusts was produced by daytime convection cells advected over the crater by strong regional daytime upslope winds, which also control aeolian surface features. One such event covered 10 times more area than the largest dust devil, suggesting that dust devils and wind gusts could raise equal amounts of dust under nonstorm conditions.

16.
Sensors (Basel) ; 22(8)2022 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-35458893

RESUMEN

The Radiation and Dust Sensor is one of six sensors of the Mars Environmental Dynamics Analyzer onboard the Perseverance rover from the Mars 2020 NASA mission. Its primary goal is to characterize the airbone dust in the Mars atmosphere, inferring its concentration, shape and optical properties. Thanks to its geometry, the sensor will be capable of studying dust-lifting processes with a high temporal resolution and high spatial coverage. Thanks to its multiwavelength design, it will characterize the solar spectrum from Mars' surface. The present work describes the sensor design from the scientific and technical requirements, the qualification processes to demonstrate its endurance on Mars' surface, the calibration activities to demonstrate its performance, and its validation campaign in a representative Mars analog. As a result of this process, we obtained a very compact sensor, fully digital, with a mass below 1 kg and exceptional power consumption and data budget features.


Asunto(s)
Polvo , Medio Ambiente Extraterrestre , Atmósfera
17.
J Geophys Res Planets ; 127(12): e2022JE007523, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37033152

RESUMEN

Wind speeds measured by the Mars 2020 Perseverance rover in Jezero crater were fitted as a Weibull distribution. InSight wind data acquired in Elysium Planitia were also used to contextualize observations. Jezero winds were found to be much calmer on average than in previous landing sites, despite the intense aeolian activity observed. However, a great influence of turbulence and wave activity was observed in the wind speed variations, thus driving the probability of reaching the highest wind speeds at Jezero, instead of sustained winds driven by local, regional, or large-scale circulation. The power spectral density of wind speed fluctuations follows a power-law, whose slope deviates depending on the time of day from that predicted considering homogeneous and isotropic turbulence. Daytime wave activity is related to convection cells and smaller eddies in the boundary layer, advected over the crater. The signature of convection cells was also found during dust storm conditions, when prevailing winds were consistent with a tidal drive. Nighttime fluctuations were also intense, suggesting strong mechanical turbulence. Convective vortices were usually involved in rapid wind fluctuations and extreme winds, with variations peaking at 9.2 times the background winds. Transient high wind events by vortex-passages, turbulence, and wave activity could be driving aeolian activity at Jezero. We report the detection of a strong dust cloud of 0.75-1.5 km in length passing over the rover. The observed aeolian activity had major implications for instrumentation, with the wind sensor suffering damage throughout the mission, probably due to flying debris advected by winds.

18.
J Neurointerv Surg ; 14(11): 1062-1067, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34750112

RESUMEN

BACKGROUND: The optimal endovascular treatment (EVT) technique for middle cerebral artery (MCA) M2 segment occlusions remains unknown. We aim to analyze whether reperfusion rate, procedure times, procedure-related complications, and clinical outcome differed between patients with isolated M2 occlusions who underwent stent-retriever (SR) alone versus combined SR and contact aspiration (CA) as a front-line EVT. METHODS: Patients who underwent EVT for isolated MCA-M2 occlusion were recruited from the prospectively ongoing ROSSETTI registry. Patients were divided regarding the EVT approach into SR alone versus SR+CA and propensity score matching was used to achieve baseline balance. Demographic, procedural, safety, and clinical outcomes were compared between groups. Multivariable logistic regression analysis was performed to identify independent predictors of first-pass effect (FPE) and 90-day modified Rankin scale (mRS) 0-2. RESULTS: 214 patients underwent EVT for M2 occlusion, 125 treated with SR alone and 89 with SR+CA. Propensity score matchnig analysis selected 134 matched patients. The rates of FPE (42% vs 40%, p=1.000) and 90-day mRS 0-2 (60% vs 51%, p=0.281) were comparable between groups. Patients treated with SR alone had lower need of rescue therapy (p=0.006), faster times to reperfusion (p<0.001), and lower procedure-related complications (p=0.031). Higher initial Alberta Stroke Program Early CT Score was an independent predictor of FPE. Age, baseline National Institutes of Health Stroke Scale score, and procedure duration were significant predictors of good clinical outcome at 3 months. CONCLUSIONS: As front-line modality in M2 occlusions, the SR alone approach results in similar rates of reperfusion and good clinical outcomes to combined SR+CA and might be advantageous due to faster reperfusion times and fewer adverse events.


Asunto(s)
Isquemia Encefálica , Procedimientos Endovasculares , Accidente Cerebrovascular , Isquemia Encefálica/etiología , Procedimientos Endovasculares/efectos adversos , Procedimientos Endovasculares/métodos , Humanos , Lactante , Infarto de la Arteria Cerebral Media/complicaciones , Infarto de la Arteria Cerebral Media/diagnóstico por imagen , Infarto de la Arteria Cerebral Media/cirugía , Arteria Cerebral Media/diagnóstico por imagen , Arteria Cerebral Media/cirugía , Puntaje de Propensión , Stents/efectos adversos , Accidente Cerebrovascular/etiología , Trombectomía/efectos adversos , Trombectomía/métodos , Resultado del Tratamiento
19.
J Neurointerv Surg ; 14(9): 863-867, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34452989

RESUMEN

BACKGROUND: Balloon guide catheter (BGC) in stent retriever based thrombectomy (BGC+SR) for patients with large vessel occlusion strokes (LVOS) improves outcomes. It is conceivable that the addition of a large bore distal access catheter (DAC) to BGC+SR leads to higher efficacy. We aimed to investigate whether the combined BGC+DAC+SR approach improves angiographic and clinical outcomes compared with BGC+SR alone for thrombectomy in anterior circulation LVOS. METHODS: Consecutive patients with anterior circulation LVOS from June 2019 to November 2020 were recruited from the ROSSETTI registry. Demographic, clinical, angiographic, and outcome data were compared between patients treated with BGC+SR alone versus BGC+DAC+SR. The primary outcome was first pass effect (FPE) rate, defined as near complete/complete revascularization (modified Thrombolysis in Cerebral Infarction (mTICI) 2c-3) after single device pass. RESULTS: We included 401 patients (BGC+SR alone, 273 (66.6%) patients). Patients treated with BGC+SR alone were older (median age 79 (IQR 68-85) vs 73.5 (65-82) years; p=0.033) and had shorter procedural times (puncture to revascularization 24 (14-46) vs 37 (24.5-63.5) min, p<0.001) than the BGC+DAC+SR group. Both approaches had a similar FPE rate (52% in BGC+SR alone vs 46.9% in BGC+DAC+SR, p=0.337). Although the BGC+SR alone group showed higher rates for final successful reperfusion (mTICI ≥2b (86.8% vs 74.2%, p=0.002) and excellent reperfusion, mTICI ≥2 c (76.2% vs 55.5%, p<0.001)), there were no significant differences in 24 hour National Institutes of Health Stroke Scale score or rates of good functional outcome (modified Rankin Scale score of 0-2) at 3 months across these techniques. CONCLUSIONS: Our data showed that addition of distal intracranial aspiration catheters to BGC+SR based thrombectomy in patients with acute anterior circulation LVO did not provide higher rates of FPE or improved clinical outcomes.


Asunto(s)
Isquemia Encefálica , Procedimientos Endovasculares , Accidente Cerebrovascular , Anciano , Isquemia Encefálica/diagnóstico por imagen , Isquemia Encefálica/cirugía , Catéteres , Infarto Cerebral/etiología , Procedimientos Endovasculares/métodos , Humanos , Estudios Retrospectivos , Stents/efectos adversos , Accidente Cerebrovascular/diagnóstico por imagen , Accidente Cerebrovascular/cirugía , Trombectomía/métodos , Resultado del Tratamiento
20.
Space Sci Rev ; 217(3): 48, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34776548

RESUMEN

NASA's Mars 2020 (M2020) rover mission includes a suite of sensors to monitor current environmental conditions near the surface of Mars and to constrain bulk aerosol properties from changes in atmospheric radiation at the surface. The Mars Environmental Dynamics Analyzer (MEDA) consists of a set of meteorological sensors including wind sensor, a barometer, a relative humidity sensor, a set of 5 thermocouples to measure atmospheric temperature at ∼1.5 m and ∼0.5 m above the surface, a set of thermopiles to characterize the thermal IR brightness temperatures of the surface and the lower atmosphere. MEDA adds a radiation and dust sensor to monitor the optical atmospheric properties that can be used to infer bulk aerosol physical properties such as particle size distribution, non-sphericity, and concentration. The MEDA package and its scientific purpose are described in this document as well as how it responded to the calibration tests and how it helps prepare for the human exploration of Mars. A comparison is also presented to previous environmental monitoring payloads landed on Mars on the Viking, Pathfinder, Phoenix, MSL, and InSight spacecraft.

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