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1.
J Acoust Soc Am ; 155(1): 420-435, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38240669

RESUMO

The Perseverance rover is carrying out an original acoustic experiment on Mars: the SuperCam microphone records the spherical acoustic waves generated by laser sparks at distances from 2 m to more than 8 m. These N-shaped acoustic waves scatter from the multiple local heterogeneities of the turbulent atmosphere. Therefore, large and random fluctuations of sound travel time and intensity develop as the waves cross the medium. The variances of the travel times and the scintillation index (normalized variance of the sound intensity) are studied within the mathematical formalism of the propagation of spherical acoustic waves through thermal turbulence to infer statistical properties of the Mars atmospheric temperature fluctuation field. The comparison with the theory is made by simplifying assumptions that do not include wind fluctuations and diffraction effects. Two Earth years (about one Martian year) of observations acquired during the maximum convective period (10:00-14:00 Mars local time) show a good agreement between the dataset and the formalism: the travel time variance diverges from the linear Chernov solution exactly where the density of occurrence of the first caustic reaches its maximum. Moreover, on average, waves travel faster than the mean speed of sound due to a fast path effect, which is also observed on Earth. To account for the distribution of turbulent eddies, several power spectra are tested and the best match to observation is obtained with a generalized von Karman spectrum with a shallower slope than the Kolmogorov cascade, ϕ(k)∝(1+k2L2)-4/3. It is associated with an outer scale of turbulence, L, of 11 cm at 2 m above the surface and a standard deviation of 6 K over 9 s for the temperature. These near-surface atmospheric properties are consistent with a weak to moderate wave scattering regime around noon with little saturation. Overall, this study presents an innovative and promising methodology to probe the near-surface atmospheric turbulence on Mars.

2.
Planet Space Sci ; 193: 105075, 2020 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-32904654

RESUMO

A survey around a recently-fueled MMRTG in the terrestrial atmosphere finds a warm air plume with a characteristic updraft velocity of ~1 m/s and a temperature rise of ~4 â€‹K. Additionally, a roughly hundredfold enhancement in ion density to ~70,000/cm3 in the vicinity (<~1 â€‹m) of the generator was observed: air electrical conductivity was measured to be ~10-13 â€‹S/m. No evidence of ozone production was detected. These observations inform the electrical charging environment and possible local perturbation to meteorological measurements on Mars or Titan on MMRTG-powered landers or rovers. On Mars, the effects of any electrical conductivity enhancement are likely small, but on Titan they may be significant.

3.
Orthopade ; 49(3): 211-217, 2020 Mar.
Artigo em Alemão | MEDLINE | ID: mdl-31515590

RESUMO

As a result of the complexity and diversity of diseases in the region of the groin, differentiation of the various soft-tissue and bone pathologies remains a challenge for differential diagnosis in routine clinical practice. In the case of athletes with pain localized in the area of the groin, femoroacetabular impingement (FAI) and athlete's groin must be considered as important causes of the groin pain, whereby the common occurrence of double pathologies further complicates diagnosis. Despite the importance of groin pain and its differential diagnoses in everyday clinical practice, there has been a lack of recognized recommendations for diagnostic procedure to date. To this end, a consensus meeting was held in February 2017, in which a group composed equally of groin and hip surgeons took part. With the formulation of recommendations and the establishment of a practicable diagnostic path, colleagues that are involved in treating such patients should be sensitized to this issue and the quality of the diagnosis of groin pain improved in routine clinical practice.


Assuntos
Algoritmos , Traumatismos em Atletas/diagnóstico , Impacto Femoroacetabular/diagnóstico , Hérnia/diagnóstico , Atletas , Consenso , Virilha , Humanos , Dor , Esportes
4.
Ann Surg ; 270(1): 1-9, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30921052

RESUMO

OBJECTIVE: Based on an analysis of data from the Herniamed Registry, this study aims to identify all factors influencing the outcome in female groin hernia repair. BACKGROUND: In a systematic review and meta-analysis of observational studies, female sex was found to be a significant risk factor for recurrence. In the guidelines, the totally extraperitoneal patch plasty (TEP) and transabdominal preperitoneal patch plasty (TAPP) laparo-endoscopic techniques are recommended for female groin hernia repair. However, even when complying with the guidelines, a less favorable outcome must be expected than in men. To date, there is no study in the literature for analysis of all factors influencing the outcome in female groin hernia repair. METHODS: In all, 15,601 female patients from the Herniamed Registry who had undergone primary unilateral groin hernia repair with the Lichtenstein, Shouldice, TEP or TAPP technique, and for whom 1-year follow-up was available, were selected between September 1, 2009 and July 1, 2017. Using multivariable analyses, influencing factors on the various outcome parameters were identified. RESULTS: In the multivariable analysis, a significantly higher risk of postoperative complications, complication-related reoperations, recurrences, and pain on exertion was found only for the Lichtenstein technique. No negative influence on the outcome was identified for the TEP, TAPP, or Shouldice techniques. Relevant risk factors for occurrence of perioperative complications, recurrences, and chronic pain were preoperative pain, existing risk factors, larger defects, a higher body mass index (BMI), higher American Society of Anesthesiologists (ASA) classification and postoperative complications. Higher age had a negative association with postoperative complications and positive association with pain rates. CONCLUSIONS: Female groin hernia repair should be performed with the TEP or TAPP laparo-endoscopic technique, or, alternatively, with the Shouldice technique, if there is no evidence of a femoral hernia. By contrast, the Lichtenstein technique has disadvantages in terms of postoperative complications, recurrences, and pain on exertion. Important risk factors for an unfavorable outcome are preoperative pain, existing risk factors, higher ASA classification, higher BMI, and postoperative complications. A higher age and larger defects have an unfavorable impact on postoperative complications and a more favorable impact on chronic pain.


Assuntos
Hérnia Inguinal/cirurgia , Herniorrafia/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Humanos , Complicações Intraoperatórias/epidemiologia , Complicações Intraoperatórias/etiologia , Complicações Intraoperatórias/prevenção & controle , Pessoa de Meia-Idade , Análise Multivariada , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/prevenção & controle , Recidiva , Sistema de Registros , Estudos Retrospectivos , Fatores de Risco , Resultado do Tratamento , Adulto Jovem
5.
Earth Planets Space ; 70(1): 88, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-31007533

RESUMO

The existence of lightning discharges in the Venus atmosphere has been controversial for more than 30 years, with many positive and negative reports published. The lightning and airglow camera (LAC) onboard the Venus orbiter, Akatsuki, was designed to observe the light curve of possible flashes at a sufficiently high sampling rate to discriminate lightning from other sources and can thereby perform a more definitive search for optical emissions. Akatsuki arrived at Venus during December 2016, 5 years following its launch. The initial operations of LAC through November 2016 have included a progressive increase in the high voltage applied to the avalanche photodiode detector. LAC began lightning survey observations in December 2016. It was confirmed that the operational high voltage was achieved and that the triggering system functions correctly. LAC lightning search observations are planned to continue for several years.

6.
J Acoust Soc Am ; 134(6): 4335, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25669245

RESUMO

Saturn's moon Titan is the only satellite in this solar system with a dense atmosphere and hydrocarbon seas. The Titan Mare Explorer (TiME) mission would splashdown a capsule to float for 3 months on Ligeia Mare, a several-hundred-kilometer wide sea near Titan's north pole. Among TiME's scientific goals is the determination of the depth of Ligeia, to be achieved with an acoustic depth sounder. Since Titan's surface temperature is known to vary around 92 K, all instruments must be ruggedized to operate at cryogenic temperatures. This paper's contributions include an approach to infer key acoustic properties of this remote environment and the extraterrestrial environment's influence on the development of a cryogenic depth sounder. Additionally, an approach is formulated to infer the transducer's response, sensitivity, and performance when in situ calibration is impossible or when replicating key environmental conditions is too costly.

7.
J Clin Med ; 12(3)2023 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-36769652

RESUMO

Inguinal hernia repair, according to Desarda, is a pure tissue surgical technique using external oblique fascia to reinforce the posterior wall of the inguinal canal. This has provided an impetus for the rethinking of guideline adherence toward minimally invasive and mesh-based surgery of inguinal hernia. In this study, a retrospective analysis of this technique was conducted in two German hospitals. Between 6/2013 and 12/2020, 120 operations were performed. Analysis included patient characteristics, duration of operation, length of hospital stay, and perioperative complications. Data were used to achieve a matched-pair analysis comparing Desarda to laparoscopic transabdominal preperitoneal (TAPP) hernia repair. Propensity scores were calculated based on five preoperative variables, including sex, age, American Society of Anesthesiology classification, localization, and width of the inguinal hernia in order to achieve comparability. Additionally, we assessed pain level and quality of life (QoL) 12 months postoperatively. The focus of our study was a comparison of QoL to a reference population and TAPP cohort. The study population consisted of 106 male and 14 female patients, and the median age was 37.5 years. The median operation time was 50 min, and the median length of hospital stay was 2 days. At a follow-up of 17 months, the median recurrence rate was 0.8%, and two cases of chronic postoperative pain were recorded. Postoperative QoL does not significantly differ between Desarda and TAPP. In contrast, Desarda patients had a significantly higher QoL compared with the reference population. In summary, Desarda's procedure is a good option as a pure tissue method for inguinal hernia repair.

8.
Chirurgie (Heidelb) ; 94(3): 199-209, 2023 Mar.
Artigo em Alemão | MEDLINE | ID: mdl-36602565

RESUMO

BACKGROUND: Surgery is contributing to the climate crisis, not least in the outpatient sector. The present publication aims to identify the challenges this poses, and to provide clear, preferably evidence-based recommendations on environmental protection while simultaneously reducing costs. METHOD: Narrative review with a non-systematic search and selection in PubMed/MEDLINE and grey area literature as well as expert interviews. RESULTS: Numerous primary articles, evidence syntheses, practical recommendations for action and checklists were identified and two experts were interviewed. Environmental issues were identified in the production and procurement, transport of people and goods, usage of materials, pharmaceuticals including anesthetic gases and energy consumption in the outpatient practice and also in disposal, recycling, and sterilization. High-quality publications do not describe a lack of knowledge on alternatives but on a lack of implementation in clinical practice. Therefore, the identified issues were classified in the 5­R scheme (reduce, reuse, recycle, rethink, research) to present recommendations for action, which are synergetic in terms of cost reduction, patient and staff satisfaction. Furthermore, changes in regulatory frameworks are discussed. CONCLUSION: Outpatient surgery comes with relevant consumption of resources and carbon emissions. There are numerous opportunities for action that combine environmental protection with cost reduction as well as patient and staff satisfaction. Incentives, guidelines, and legal framework conditions are needed for comprehensive environmental protection in the private sector.


Assuntos
Anestésicos Inalatórios , Humanos , Conservação dos Recursos Naturais , Prática Privada
9.
Coloproctology ; : 1-10, 2023 May 04.
Artigo em Alemão | MEDLINE | ID: mdl-37362611

RESUMO

Background: Surgery is contributing to the climate crisis, not least in the outpatient sector. The present publication aims to identify the challenges this poses, and to provide clear, preferably evidence-based recommendations on environmental protection while simultaneously reducing costs. Method: Narrative review with a non-systematic search and selection in PubMed/MEDLINE and grey area literature as well as expert interviews. Results: Numerous primary articles, evidence syntheses, practical recommendations for action and checklists were identified and two experts were interviewed. Environmental issues were identified in the production and procurement, transport of people and goods, usage of materials, pharmaceuticals including anesthetic gases and energy consumption in the outpatient practice and also in disposal, recycling, and sterilization. High-quality publications do not describe a lack of knowledge on alternatives but on a lack of implementation in clinical practice. Therefore, the identified issues were classified in the 5­R scheme (reduce, reuse, recycle, rethink, research) to present recommendations for action, which are synergetic in terms of cost reduction, patient and staff satisfaction. Furthermore, changes in regulatory frameworks are discussed. Conclusion: Outpatient surgery comes with relevant consumption of resources and carbon emissions. There are numerous opportunities for action that combine environmental protection with cost reduction as well as patient and staff satisfaction. Incentives, guidelines, and legal framework conditions are needed for comprehensive environmental protection in the private sector.

10.
BJS Open ; 7(5)2023 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-37862616

RESUMO

BACKGROUND: Groin hernia repair is one of the most common operations performed globally, with more than 20 million procedures per year. The last guidelines on groin hernia management were published in 2018 by the HerniaSurge Group. The aim of this project was to assess new evidence and update the guidelines. The guideline is intended for general and abdominal wall surgeons treating adult patients with groin hernias. METHOD: A working group of 30 international groin hernia experts and all involved stakeholders was formed and examined all new literature on groin hernia management, available until April 2022. Articles were screened for eligibility and assessed according to GRADE methodologies. New evidence was included, and chapters were rewritten. Statements and recommendations were updated or newly formulated as necessary. RESULTS: Ten chapters of the original HerniaSurge inguinal hernia guidelines were updated. In total, 39 new statements and 32 recommendations were formulated (16 strong recommendations). A modified Delphi method was used to reach consensus on all statements and recommendations among the groin hernia experts and at the European Hernia Society meeting in Manchester on October 21, 2022. CONCLUSION: The HerniaSurge Collaboration has updated the international guidelines for groin hernia management. The updated guidelines provide an overview of the best available evidence on groin hernia management and include evidence-based statements and recommendations for daily practice. Future guideline development will change according to emerging guideline methodology.


Assuntos
Parede Abdominal , Hérnia Inguinal , Adulto , Humanos , Hérnia Inguinal/cirurgia , Virilha/cirurgia , Telas Cirúrgicas
11.
Astrobiology ; 22(9): 1047-1060, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35972349

RESUMO

Landed missions to icy worlds with a subsurface liquid water ocean must meet planetary protection requirements and ensure a sufficiently small likelihood of any microorganism-bearing part of the landed element reaching the ocean. A higher bound on this likelihood is set by the potential for radioisotope thermoelectric generator (RTG) power sources, the hottest possible landed element, to melt through the ice shell and reach the ocean. In this study, we quantify this potential as a function of three key parameters: surface temperature, ice shell thickness (i.e., heat flux through the shell), and thickness of a porous (insulating) snow or regolith cover. Although the model we describe can be applied to any ocean world, we present results in the context of a landed mission concept to the south polar terrain of Saturn's moon Enceladus. In this particular context, we discuss planetary protection considerations for landing site selection. The likelihood of forward microbial contamination of Enceladus' ocean by an RTG-powered landed mission can be made sufficiently low to not undermine compliance with the planetary protection policy.


Assuntos
Meio Ambiente Extraterreno , Gelo , Oceanos e Mares , Planetas , Radioisótopos
12.
Sci Adv ; 8(21): eabn3783, 2022 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-35613267

RESUMO

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.

13.
Nature ; 438(7069): 792-5, 2005 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-16319828

RESUMO

The surface of Saturn's largest satellite--Titan--is largely obscured by an optically thick atmospheric haze, and so its nature has been the subject of considerable speculation and discussion. The Huygens probe entered Titan's atmosphere on 14 January 2005 and descended to the surface using a parachute system. Here we report measurements made just above and on the surface of Titan by the Huygens Surface Science Package. Acoustic sounding over the last 90 m above the surface reveals a relatively smooth, but not completely flat, surface surrounding the landing site. Penetrometry and accelerometry measurements during the probe impact event reveal that the surface was neither hard (like solid ice) nor very compressible (like a blanket of fluffy aerosol); rather, the Huygens probe landed on a relatively soft solid surface whose properties are analogous to wet clay, lightly packed snow and wet or dry sand. The probe settled gradually by a few millimetres after landing.

14.
Earth Space Sci ; 7(5): e2019EA000992, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32715027

RESUMO

Records of solar array currents recorded by the InSight lander during its first 200 sols on Mars are presented. In addition to the geometric variation in illumination on seasonal and diurnal timescales, the data are influenced by dust suspended in the atmosphere and deposited on the solar panels. Although no dust devils have been detected by InSight's cameras, brief excursions in solar array currents suggest that at least some of the vortices detected by transient pressure drops are accompanied by dust. A step increase in array output (i.e., a "cleaning event") was observed to be directly associated with the passage of a strong vortex. Some quasiperiodic variations in solar array current are suggestive of dust variations in the planetary boundary layer. Nonzero array outputs before sunrise and after sunset are indicative of scattering in the atmosphere: A notable increase in evening twilight currents is observed associated with noctilucent clouds, likely of water or carbon dioxide ice. Finally, although the observations are intermittent (typically a few hours per sol) and at a modest sample rate (one to two samples per minute), three single-sample light dips are seen associated with Phobos eclipses. These results demonstrate that engineering data from solar arrays provide valuable scientific situational awareness of the Martian environment.

15.
Nat Commun ; 11(1): 2829, 2020 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-32546817

RESUMO

Saturn's moon Titan has a methane cycle with clouds, rain, rivers, lakes, and seas; it is the only world known to presently have a volatile cycle akin to Earth's tropospheric water cycle. Anomalously specular radar reflections (ASRR) from Titan's tropical region were observed with the Arecibo Observatory (AO) and Green Bank Telescope (GBT) and interpreted as evidence for liquid surfaces. The Cassini spacecraft discovered lakes/seas on Titan, however, it did not observe lakes/seas at the AO/GBT anomalously specular locations. A satisfactory explanation for the ASRR has been elusive for more than a decade. Here we show that the ASRR originate from one terrain unit, likely paleolakes/paleoseas. Titan observations provide ground-truth in the search for oceans on exoearths and an important lesson is that identifying liquid surfaces by specular reflections requires a stringent definition of specular; we propose a definition for this purpose.

16.
Front Surg ; 6: 4, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30805345

RESUMO

Background: To date, there are few studies and no systematic reviews focusing specifically on groin hernia in women. Most of the existing knowledge comes from registry data. Objective: This present review now reports on such findings as are available on groin hernia in women. Materials and Methods: A systematic search of the available literature was performed in September 2018 using Medline, PubMed, Google Scholar, and the Cochrane Library. For the present analysis 80 publications were identified. Results: The lifetime risk of developing a groin hernia in women is 3-5.8%. The proportion of women in the overall collective of operated groin hernias is 8.0-11.5%. In women, the proportion of femoral hernias is 16.7-37%. Risk factors for development of a groin hernia in women of high age and with a positive family history. A groin hernia during pregnancy should not be operated on. The rate of emergency procedures in women, at 14.5-17.0%, is 3 to 4-fold higher than in men and at 40.6% is even higher for femoral hernia. Therefore, watchful waiting is not indicated in women. During surgical repair of groin hernia in females the presence of a femoral hernia should always be excluded and if detected should be repaired using a laparo-endoscopic or open preperitoneal mesh technique. A higher rate of chronic postoperative inguinal pain must be expected in females. Conclusion: Special characteristics must be taken into account for repair of groin hernia in women.

17.
Front Surg ; 6: 1, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30746364

RESUMO

Introduction: Recently, the promising results of new procedures for the treatment of rectus diastasis with concomitant hernias using extraperitoneal mesh placement and anatomical restoration of the linea alba were published. To date, there is no recognized classification of rectus diastasis (RD) with concomitant hernias. This is urgently needed for comparative assessment of new surgical techniques. A working group of the German Hernia Society (DHG) and the International Endohernia Society (IEHS) set itself the task of devising such a classification. Materials and Methods: A systematic search of the available literature was performed up to October 2018 using Medline, PubMed, Scopus, Embase, Springer Link, and the Cochrane Library. A meeting of the working group was held in May 2018 in Hamburg. For the present analysis 30 publications were identified as relevant. Results: In addition to the usual patient- and technique-related influencing factors on the outcome of hernia surgery, a typical means of rectus diastasis classification and diagnosis should be devised. Here the length of the rectus diastasis should be classified in terms of the respective subxiphoidal, epigastric, umbilical, infraumbilical, and suprapubic sectors affected as well as by the width in centimeters, whereby W1 < 3 cm, W2 = 3- ≤ 5 cm, and W3 > 5 cm. Furthermore, gender, the concomitant hernias, previous abdominal surgery, number of pregnancies and multiple births, spontaneous birth or caesarian section, skin condition, diagnostic procedures and preoperative pain rate and localization of pain should be recorded. Conclusion: Such a unique classification is needed for assessment of the treatment results in patients with RD.

18.
Astrobiology ; 18(5): 607-618, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-27870548

RESUMO

A scale model of the proposed Titan Mare Explorer capsule was deployed at the Planetary Lake Lander field site at Laguna Negra, Chile. The tests served to calibrate models of wind-driven drift of the capsule and to understand its attitude motion in the wave field, as well as to identify dynamic and acoustic signatures of shoreline approach. This information enables formulation of onboard trigger criteria for near-shore science data acquisition. Key Words: Titan-Vehicle dynamics-Science autonomy-Lake. Astrobiology 18, 607-618.


Assuntos
Exobiologia/instrumentação , Oceanos e Mares , Saturno , Chile , Lagos , Espectrometria de Massas
19.
Icarus ; 300: 200-202, 2018 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-30524143

RESUMO

The plumes of Enceladus are of interest both as a geophysical phemonenon, and as an astrobiological opportunity for sampling internal material. Here we report measurements of the total mass density (gas plus dust, a combination not reported before except in the engineering literature) deduced from telemetry of Cassini's Attitude and Articulation Control System (AACS), as the spacecraft's thrusters or reaction wheels worked to maintain the desired attitude in the presence of gas drag torques during close flybys. The drag torque shows good agreement with the water vapor density measured by other instruments during the E5 encounter, but indicates a rather higher mass density on other passes (E3,E14), possibly indicating variations in gas composition and/or gas:dust ratio. The spacecraft appears to have intercepted about 0.2 grams of material, on flyby E21 in October 2015 indicating a peak mass density of ~5.5×10-11 kgm-3, the highest of all the flybys measured (E3,E5,E7,E9,E14,E21).

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