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1.
Birth ; 49(4): 697-708, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35373861

RESUMO

BACKGROUND: The safety of waterbirth is contested because of the lack of evidence from randomized trials and conflicting results. This research assessed the feasibility of a prospective study of waterbirth (trial or cohort). METHODS: We conducted a prospective cohort study at an Australian maternity hospital. Eligible women with uncomplicated pregnancies at 36 weeks of gestation were recruited and surveyed about their willingness for randomization. The primary midwife assessed waterbirth eligibility and intention on admission in labor, and onset of second stage. Primary outcomes measured feasibility. Intention-to-treat analysis, and per-protocol analysis, compared clinical outcomes of women and their babies who intended waterbirth and nonwaterbirth at onset of second stage. RESULTS: 1260 participants were recruited; 15% (n = 188) agreed to randomization in a future trial. 550 women were analyzed by intention-to-treat analysis: 351 (waterbirth) and 199 (nonwaterbirth). In per-protocol analysis, 14% (n = 48) were excluded. Women in the waterbirth group were less likely to have amniotomy and more likely to have water immersion and physiological third stage. There were no differences in other measures of maternal morbidity. There were no significant differences between groups for serious neonatal morbidity; four cord avulsions occurred in the waterbirth group with none in the landbirth group. An RCT would need approximately 6000 women to be approached at onset of second stage. CONCLUSIONS: A randomized trial of waterbirth compared with nonwaterbirth, powered to detect a difference in serious neonatal morbidity, is unlikely to be feasible. A powered prospective study with intention-to-treat analysis at onset of second stage is feasible.


Assuntos
Tocologia , Parto Normal , Recém-Nascido , Feminino , Gravidez , Humanos , Parto Normal/métodos , Estudos Prospectivos , Estudos de Viabilidade , Austrália
2.
Curr Opin Anaesthesiol ; 34(2): 125-130, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33577206

RESUMO

PURPOSE OF REVIEW: More than 8.5 million people in the world observe the Jehovah's Witness faith, and require unique consideration for perioperative blood management as they generally refuse transfusion of blood and blood products. This review addresses a collaborative approach to each patient throughout the perioperative arena. The principles of this approach include optimization of hemoglobin levels preoperatively, attention to blood-salvaging methods intraoperatively, and minimization of blood draws postoperatively. In addition, we review the technologies currently in development as transfusion alternatives, including hemoglobin-based oxygen carriers. RECENT FINDINGS: Progress has been made recently in the field of synthetic blood alternatives and hemoglobin-based oxygen carriers, which may lead to improved outcomes in this patient population. SUMMARY: Utilization of multiple prevention and mitigation strategies to optimize oxygen supply and decrease oxygen demand will lead to decreased incidence of critical anemia and subsequent improved mortality in Jehovah's Witness patients.


Assuntos
Transfusão de Sangue , Testemunhas de Jeová , Anemia/prevenção & controle , Hemoglobinas , Humanos
3.
Lancet ; 394(10198): 565-575, 2019 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-31280969

RESUMO

BACKGROUND: Loss of upper extremity function after cervical spinal cord injury greatly affects independence, including social, vocational, and community engagement. Nerve transfer surgery offers an exciting new option for the reanimation of upper limb function in tetraplegia. The aim of this study was to evaluate the outcomes of nerve transfer surgery used for the reanimation of upper limb function in tetraplegia. METHODS: In this prospective case series, we consecutively recruited people of any age with early (<18 months post-injury) cervical spinal cord injury of motor level C5 and below, who had been referred to a single centre for upper extremity reanimation and were deemed suitable for nerve transfer. All participants underwent single or multiple nerve transfers in one or both upper limbs, sometimes combined with tendon transfers, for restoration of elbow extension, grasp, pinch, and hand opening. Participants were assessed at 12 months and 24 months post-surgery. Primary outcome measures were the action research arm test (ARAT), grasp release test (GRT), and spinal cord independence measure (SCIM). FINDINGS: Between April 14, 2014, and Nov 22, 2018, we recruited 16 participants (27 limbs) with traumatic spinal cord injury, among whom 59 nerve transfers were done. In ten participants (12 limbs), nerve transfers were combined with tendon transfers. 24-month follow-up data were unavailable for three patients (five limbs). At 24 months, significant improvements from baseline in median ARAT total score (34·0 [IQR 24·0-38·3] at 24 months vs 16·5 [12·0-22·0] at baseline, p<0·0001) and GRT total score (125·2 [65·1-154·4] vs 35·0 [21·0-52·3], p<0·0001) were observed. Mean total SCIM score and mobility in the room and toilet SCIM score improved by more than the minimal detectable change and the minimal clinically important difference, and the mean self-care SCIM score improved by more than the minimal detectable change between baseline and 24 months. Median Medical Research Council strength grades were 3 (IQR 2-3) for triceps and 4 (IQR 4-4) for digital extensor muscles after 24 months. Mean grasp strength at 24 months was 3·2 kg (SD 1·5) in participants who underwent distal nerve transfers (n=5), 2·8 kg (3·2) in those who had proximal nerve transfers (n=9), and 3·9 kg (2·4) in those who had tendon transfers (n=8). There were six adverse events related to the surgery, none of which had any ongoing functional consequences. INTERPRETATION: Early nerve transfer surgery is a safe and effective addition to surgical techniques for upper limb reanimation in tetraplegia. Nerve transfers can lead to significant functional improvement and can be successfully combined with tendon transfers to maximise functional benefits. FUNDING: Institute for Safety, Compensation, and Recovery Research (Australia).


Assuntos
Transferência de Nervo/métodos , Quadriplegia/cirurgia , Transferência Tendinosa/métodos , Extremidade Superior/fisiopatologia , Adolescente , Adulto , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Quadriplegia/fisiopatologia , Recuperação de Função Fisiológica , Resultado do Tratamento , Extremidade Superior/inervação , Extremidade Superior/cirurgia , Adulto Jovem
4.
New Dir Child Adolesc Dev ; 2020(172): 135-149, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32960503

RESUMO

Although developmental science has always been evolving, these times of fast-paced and profound social and scientific changes easily lead to disorienting fragmentation rather than coherent scientific advances. What directions should developmental science pursue to meaningfully address real-world problems that impact human development throughout the lifespan? What conceptual or policy shifts are needed to steer the field in these directions? The present manifesto is proposed by a group of scholars from various disciplines and perspectives within developmental science to spark conversations and action plans in response to these questions. After highlighting four critical content domains that merit concentrated and often urgent research efforts, two issues regarding "how" we do developmental science and "what for" are outlined. This manifesto concludes with five proposals, calling for integrative, inclusive, transdisciplinary, transparent, and actionable developmental science. Specific recommendations, prospects, pitfalls, and challenges to reach this goal are discussed.


Assuntos
Ciências Biocomportamentais , Psicologia do Desenvolvimento , Ciências Biocomportamentais/métodos , Ciências Biocomportamentais/normas , Ciências Biocomportamentais/tendências , Humanos , Psicologia do Desenvolvimento/métodos , Psicologia do Desenvolvimento/normas , Psicologia do Desenvolvimento/tendências
5.
Am J Hum Biol ; 30(4): e23125, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29637643

RESUMO

OBJECTIVES: We measured carbon and nitrogen isotopic ratios in a contemporary population, and tested how the isotopic variability relates to measures of socioeconomic status (e.g., household wealth) and anthropometric measures (e.g., standardized height-for-age and weight-for-age z-scores). METHODS: Hair samples from individuals living in the Bosawas Biosphere Reserve in Nicaragua were analyzed for δ13 C and δ15 N, and these data were examined in relation to individual (e.g., age, sex, anthropometrics) and household (e.g., household size, wealth) variables. RESULTS: We found through mixed-effects modeling that δ13 C and δ15 N varied predictably with individual age and household wealth. δ13 C and δ15 N did not, however, improve models predicting variation in individual anthropometric measures. CONCLUSION: These results indicate that, although there is a relationship between diet (δ13 C and δ15 N) and socioeconomic variables, these dietary differences are not the main cause of health differences in this population.


Assuntos
Dieta , Pessoa de Meia-Idade , Avaliação Nutricional , Estado Nutricional , Classe Social , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Demografia , Feminino , Humanos , Masculino , Nicarágua , Adulto Jovem
6.
New Dir Child Adolesc Dev ; 2018(160): 75-87, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29633538

RESUMO

This article considers how the global "academic pipeline problem" constrains immigrant, low-income, and ethnic minority students' pathways to higher education, and how some students build pathways to college and career identities. After aligning theories of social capital, alienation/belonging, and challenge and their integration in Bridging Multiple Worlds Theory, we summarize six longitudinal studies based on this theory from a 23-year university-community partnership serving low-income, primarily U.S. Mexican immigrant youth. Spanning from childhood to early adulthood, the studies revealed two overarching findings: First, students built pathways to college and career identities while experiencing capital, alienation/belonging, and challenges across their evolving cultural worlds. Second, by "giving back" to families, peers, schools, and communities, students became cultural brokers and later, institutional agents, transforming institutional cultures. Findings highlight the value of integrating interdisciplinary theories, research evidence, and educational systems serving diverse communities to open individual pathways and academic pipelines in multicultural societies.


Assuntos
Escolha da Profissão , Emigrantes e Imigrantes/psicologia , Americanos Mexicanos/psicologia , Alienação Social/psicologia , Capital Social , Identificação Social , Estudantes/psicologia , Universidades , Adolescente , Adulto , Criança , Humanos , México/etnologia , Estados Unidos/etnologia , Adulto Jovem
7.
Bull World Health Organ ; 95(7): 526-530, 2017 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-28670017

RESUMO

PROBLEM: The lack of proper water and sanitation infrastructures and poor hygiene practices in health-care facilities reduces facilities' preparedness and response to disease outbreaks and decreases the communities' trust in the health services provided. APPROACH: To improve water and sanitation infrastructures and hygiene practices, the Liberian health ministry held multistakeholder meetings to develop a national water, sanitation and hygiene and environmental health package. A national train-the-trainer course was held for county environmental health technicians, which included infection prevention and control focal persons; the focal persons acted as change agents. LOCAL SETTING: In Liberia, only 45% of 701 surveyed health-care facilities had an improved water source in 2015, and only 27% of these health-care facilities had proper disposal for infectious waste. RELEVANT CHANGES: Local ownership, through engagement of local health workers, was introduced to ensure development and refinement of the package. In-county collaborations between health-care facilities, along with multisectoral collaboration, informed national level direction, which led to increased focus on water and sanitation infrastructures and uptake of hygiene practices to improve the overall quality of service delivery. LESSONS LEARNT: National level leadership was important to identify a vision and create an enabling environment for changing the perception of water, sanitation and hygiene in health-care provision. The involvement of health workers was central to address basic infrastructure and hygiene practices in health-care facilities and they also worked as stimulators for sustainable change. Further, developing a long-term implementation plan for national level initiatives is important to ensure sustainability.


Assuntos
Administração de Instituições de Saúde/normas , Higiene/normas , Saneamento/métodos , Abastecimento de Água/métodos , Atitude do Pessoal de Saúde , Comportamento Cooperativo , Países em Desenvolvimento , Humanos , Controle de Infecções/organização & administração , Relações Interinstitucionais , Liderança , Libéria , Desenvolvimento de Programas , Avaliação de Programas e Projetos de Saúde , Saneamento/normas , Abastecimento de Água/normas
8.
BMC Med ; 14: 2, 2016 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-26732586

RESUMO

Prior to the 2014-2015 Ebola outbreak, infection prevention and control (IPC) activities in Liberian healthcare facilities were basic. There was no national IPC guidance, nor dedicated staff at any level of government or healthcare facility (HCF) to ensure the implementation of best practices. Efforts to improve IPC early in the outbreak were ad hoc and messaging was inconsistent. In September 2014, at the height of the outbreak, the national IPC Task Force was established with a Ministry of Health (MoH) mandate to coordinate IPC response activities. A steering group of the Task Force, including representatives of the World Health Organization (WHO) and the United States Centers for Disease Control and Prevention (CDC), supported MoH leadership in implementing standardized messaging and IPC training for the health workforce. This structure, and the activities implemented under this structure, played a crucial role in the implementation of IPC practices and successful containment of the outbreak. Moving forward, a nationwide culture of IPC needs to be maintained through this governance structure in Liberia's health system to prevent and respond to future outbreaks.


Assuntos
Surtos de Doenças/prevenção & controle , Doença pelo Vírus Ebola/epidemiologia , Doença pelo Vírus Ebola/prevenção & controle , Controle de Infecções/organização & administração , Comitês Consultivos/organização & administração , Pessoal de Saúde/educação , Doença pelo Vírus Ebola/transmissão , Humanos , Controle de Infecções/normas , Internacionalidade , Libéria/epidemiologia , Isolamento de Pacientes/organização & administração , Isolamento de Pacientes/normas , Estados Unidos , Organização Mundial da Saúde
9.
Arch Phys Med Rehabil ; 97(6 Suppl): S160-8, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27233591

RESUMO

Despite being a routine part of the early surgical management of brachial plexus injury, nerve transfers have only recently been used as a reconstructive option for those with tetraplegia. Subsequently, there is limited published literature on the rehabilitation theories and techniques for optimizing outcomes in this population. This article seeks to address this void by presenting our centers' working model for rehabilitation after nerve transfers for individuals with tetraplegia. The model is illustrated with the example of the rehabilitation process after a supinator nerve to posterior interosseous nerve transfer. This nerve transfer reconstructs wrist, finger, and thumb extension. The topics covered in the model include the following: patient selection and presurgical planning/intervention, managing the postoperative healing phase of an individual who is wheelchair dependent, maximizing motor reeducation, increasing muscle strength, and ensuring use in functional tasks. This article provides a platform for further development and collaboration to improve the outcomes of patients who undergo nerve transfers after tetraplegia.


Assuntos
Transferência de Nervo/reabilitação , Modalidades de Fisioterapia , Quadriplegia/reabilitação , Quadriplegia/cirurgia , Extremidade Superior/cirurgia , Dedos/fisiologia , Humanos , Força Muscular , Músculo Esquelético , Transferência de Nervo/métodos , Seleção de Pacientes , Quadriplegia/etiologia , Traumatismos da Medula Espinal/complicações , Fatores de Tempo , Extremidade Superior/fisiopatologia , Punho/fisiologia
10.
Aust N Z J Obstet Gynaecol ; 55(3): 294-7, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26053591

RESUMO

A clinical audit was undertaken before and after the introduction of a five-minute video presentation as an adjunct to the clinical consultation in the setting of ruptured membranes at term. The video framed clinical information using an INFORM structure: providing Information, Facts, Options, Reasons, Meaning. Subsequently, women were more likely to report that information was unbiased, based on facts and evidence that they were involved in the decision-making and overall satisfied with the information provided.


Assuntos
Tomada de Decisões , Ruptura Prematura de Membranas Fetais/terapia , Educação de Pacientes como Assunto/métodos , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Trabalho de Parto Induzido , Gravidez , Medição de Risco , Inquéritos e Questionários , Gravação em Vídeo , Conduta Expectante
11.
J Hand Surg Am ; 39(9): 1779-83, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25063391

RESUMO

Restoration of elbow extension, grasp, key pinch, and release are major goals in low-level tetraplegia. Traditionally, these functions are achieved using tendon transfers. In this case these goals were achieved using nerve transfers. We present a 21-year-old man with a C6 level of tetraplegia. The left upper limb was treated 6 months after injury with a triple nerve transfer. A teres minor nerve branch to long head of triceps nerve branch, brachialis nerve branch to anterior interosseous nerve, and supinator nerve branch to posterior interosseous nerve transfer were used successfully to reconstruct elbow extension, key pinch, grasp, and release simultaneously.


Assuntos
Vértebras Cervicais/lesões , Transferência de Nervo/métodos , Procedimentos Neurocirúrgicos/métodos , Quadriplegia , Extremidade Superior/inervação , Extremidade Superior/cirurgia , Mergulho/lesões , Humanos , Imageamento por Ressonância Magnética , Masculino , Adulto Jovem
12.
Langmuir ; 29(41): 12670-8, 2013 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-24059561

RESUMO

The competition between poly(vinylpyrrolidone) and poly(ethylene oxide) for adsorption at the silica surface was studied by solvent relaxation nuclear magnetic resonance and small-angle neutron scattering. The additive nature of the NMR relaxation rate enhancement was used to observe changes in the train layer when the two polymers were in direct competition for an increasing weight percentage of silica. PVP is shown to displace preadsorbed PEO from the particle surface, and this was observed for a range of PVP molecular weights. SANS measurements were found to give detailed information on the adsorption of the polymers in the separate systems; however, only qualitative information on the adsorption of the polymers could be obtained from the mixed samples. At a total polymer concentration of 0.4% w/v with 1.1% w/v silica, the SANS data were consistent with PVP adsorbing at the surface and dPEO remaining in solution, in agreement with the NMR data.

14.
PM R ; 15(11): 1466-1477, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37041724

RESUMO

OBJECTIVE: The purpose of this systematic review with meta-analysis was to investigate the effect of early physical therapy (PT) for the management of acute low back pain (LBP) on patient-reported outcomes of pain and disability, compared to delayed PT or non-PT care. LITERATURE SURVEY: Randomized controlled trials in three electronic databases (MEDLINE, CINAHL, Embase) were searched from inception to June 12, 2020, and updated on September 23, 2021. METHODOLOGY: Eligible participants were individuals with acute low back pain. The intervention was early PT compared to delayed PT or non-PT care. Primary outcomes included the patient-reported outcomes of pain and disability. The following information was extracted from included articles: demographic data, sample size, selection criteria, PT interventions, and pain and disability outcomes. Data were extracted following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Methodological quality was assessed using the Physiotherapy Evidence Database (PEDro) Scale. Random effects models were used for the meta-analysis. SYNTHESIS: Seven of 391 articles met the eligibility criteria and were included in the meta-analysis. Random effects meta-analysis comparing early PT to non-PT care for acute LBP indicated a significant reduction in pain (standard mean difference [SMD] = 0.43, 95% confidence interval [CI]: -0.69 to -0.17) and disability (SMD = 0.36, 95% CI: -0.57 to -0.16) in the short term. Early PT compared to delayed PT did not result in improvement in short-term pain (SMD = -0.24, 95% CI: -0.52 to 0.04) or disability (SMD = 0.28, 95% CI: -0.56 to 0.01), or long-term pain (SMD = 0.21, 95% CI: -0.15 to 0.57) or disability (SMD = 0.14, 95% CI: -0.15 to 0.42). CONCLUSIONS: This systematic review and meta-analysis suggest early PT versus non-PT care is associated with statistically significant reductions in short-term pain and disability (up to 6 weeks) with small effect sizes. The results indicate a nonsignificant trend favoring a small benefit of early PT over delayed PT for outcomes at short-term follow-up but no effect at long-term follow-up (6 months or greater).


Assuntos
Dor Aguda , Dor Crônica , Dor Lombar , Humanos , Dor Lombar/terapia , Dor Crônica/terapia , Ensaios Clínicos Controlados Aleatórios como Assunto , Modalidades de Fisioterapia , Medidas de Resultados Relatados pelo Paciente
15.
J Geophys Res Planets ; 128(1): e2022JE007185, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37034460

RESUMO

The Mars Science Laboratory rover, Curiosity, explored the clay mineral-bearing Glen Torridon region for 1 Martian year between January 2019 and January 2021, including a short campaign onto the Greenheugh pediment. The Glen Torridon campaign sought to characterize the geology of the area, seek evidence of habitable environments, and document the onset of a potentially global climatic transition during the Hesperian era. Curiosity roved 5 km in total throughout Glen Torridon, from the Vera Rubin ridge to the northern margin of the Greenheugh pediment. Curiosity acquired samples from 11 drill holes during this campaign and conducted the first Martian thermochemolytic-based organics detection experiment with the Sample Analysis at Mars instrument suite. The lowest elevations within Glen Torridon represent a continuation of lacustrine Murray formation deposits, but overlying widespread cross bedded sandstones indicate an interval of more energetic fluvial environments and prompted the definition of a new stratigraphic formation in the Mount Sharp group called the Carolyn Shoemaker formation. Glen Torridon hosts abundant phyllosilicates yet remains compositionally and mineralogically comparable to the rest of the Mount Sharp group. Glen Torridon samples have a great diversity and abundance of sulfur-bearing organic molecules, which are consistent with the presence of ancient refractory organic matter. The Glen Torridon region experienced heterogeneous diagenesis, with the most striking alteration occurring just below the Siccar Point unconformity at the Greenheugh pediment. Results from the pediment campaign show that the capping sandstone formed within the Stimson Hesperian aeolian sand sea that experienced seasonal variations in wind direction.

16.
Langmuir ; 28(48): 16588-95, 2012 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-23137265

RESUMO

The competitive adsorption of poly(vinylpyrrolidone) onto silica and alumina-modified silica particles was studied using solvent relaxation nuclear magnetic resonance. The additive nature of the measured relaxation rate enabled predictions to be made of the relaxation rate in different polymer adsorption scenarios. Preferential adsorption of the poly(vinylpyrrolidone) onto the unmodified silica particles occurred when there was insufficient polymer in the system to coat the entire available surface area. Desorption was also found to occur when the polymer was initially adsorbed upon the alumina-modified particle and silica particles were added.

17.
J Thorac Cardiovasc Surg ; 164(6): 1672-1680.e3, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35659124

RESUMO

BACKGROUND: This study evaluated the impact of anatomic aortic root parameters during valve-sparing root replacement on the probability of postoperative aortic insufficiency and freedom from aortic valve reoperation. METHODS: From 1995 to 2020, 177 patients underwent valve-sparing root replacement (163 reimplantations, 14 remodeling). Preoperative and postoperative echocardiograms were analyzed to measure annulus and sinus diameters, effective height of leaflet coaptation, and degree of aortic insufficiency. Logistic regression was used to evaluate predictors of 2+ or greater late postoperative aortic insufficiency. Fine-Gray regression determined predictors for aortic valve reintervention. RESULTS: The study population included 122 (69%) men with a mean age of 43 ± 15 years. A total of 119 patients (67%) had an identified connective tissue disorder. The cumulative incidence of aortic valve reoperation was estimated as 7% at 5 years and 12% at 10 years. The probability of 2+ or greater late postoperative aortic insufficiency was inversely related to effective height during valve-sparing root replacement (P = .018). As postoperative effective height fell below 11 mm, the probability of 2+ or greater aortic insufficiency exceeded 10%. On multivariable logistic regression, effective height (odds ratio, 0.53; 0.33-0.86; P = .010), preoperative annulus diameter (odds ratio, 1.44; 1.13-1.82; P = .003), and degree of preoperative aortic insufficiency (odds ratio, 2.57; 1.45-4.52; P = .001) were associated with increased incidence of 2+ or greater late postoperative aortic insufficiency. On multivariable Fine-Gray regression, risk factors for aortic valve reintervention included preoperative annulus diameter (subdistribution hazard ratio, 1.28 [1.03-1.59], P = .027), history of 3+ or greater aortic insufficiency (subdistribution hazard ratio, 4.28; 1.60-11.44; P = .004), and 2+ or greater early postoperative aortic insufficiency (subdistribution hazard ratio, 5.22; 2.29-11.90; P < .001). CONCLUSIONS: Measures to increase effective height during valve-sparing root replacement may decrease the risk of more than mild postoperative aortic insufficiency after repair and the need for aortic valve reoperation.


Assuntos
Insuficiência da Valva Aórtica , Implante de Prótese de Valva Cardíaca , Humanos , Masculino , Adulto , Pessoa de Meia-Idade , Feminino , Valva Aórtica/diagnóstico por imagem , Valva Aórtica/cirurgia , Reoperação/efeitos adversos , Resultado do Tratamento , Insuficiência da Valva Aórtica/diagnóstico por imagem , Insuficiência da Valva Aórtica/cirurgia , Insuficiência da Valva Aórtica/etiologia , Implante de Prótese de Valva Cardíaca/efeitos adversos , Estudos Retrospectivos
18.
J Geophys Res Planets ; 127(11): e2022JE007492, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37035521

RESUMO

A nearly pole-to-pole survey near 140°E longitude on Europa revealed many areas that exhibit past lateral surface motions, and these areas were examined to determine whether the motions can be described by systems of rigid plates moving across Europa's surface. Three areas showing plate-like behavior were examined in detail to determine the sequence of events that deformed the surface. All three areas were reconstructed to reveal the original pre-plate motion surfaces by performing multi-stage rotations of plates in spherical coordinates. Several motions observed along single plate boundaries were also noted in previous works, but this work links together isolated observations of lateral offsets into integrated systems of moving plates. Not all of the surveyed surface could be described by systems of rigid plates. There is evidence that the plate motions did not all happen at the same time, and that they are not happening today. We conclude that plate tectonic-like behavior on Europa occurs episodically, in limited regions, with less than 100 km of lateral motion accommodated along any particular boundary before plate motions cease. Europa may represent a world perched on the theoretical boundary between stagnant and mobile lid convective behavior, or it may represent an additional example of the wide variations in possible planetary convective regimes. Differences in observed strike-slip sense and plate rotation directions between the northern and southern hemispheres raise the question of whether tidal forces may influence plate motions.

19.
J Geophys Res Planets ; 127(6): e2021JE007096, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35865672

RESUMO

Gale crater, the field site for NASA's Mars Science Laboratory Curiosity rover, contains a diverse and extensive record of aeolian deposition and erosion. This study focuses on a series of regularly spaced, curvilinear, and sometimes branching bedrock ridges that occur within the Glen Torridon region on the lower northwest flank of Aeolis Mons, the central mound within Gale crater. During Curiosity's exploration of Glen Torridon between sols ∼2300-3080, the rover drove through this field of ridges, providing the opportunity for in situ observation of these features. This study uses orbiter and rover data to characterize ridge morphology, spatial distribution, compositional and material properties, and association with other aeolian features in the area. Based on these observations, we find that the Glen Torridon ridges are consistent with an origin as wind-eroded bedrock ridges, carved during the exhumation of Mount Sharp. Erosional features like the Glen Torridon ridges observed elsewhere on Mars, termed periodic bedrock ridges (PBRs), have been interpreted to form transverse to the dominant wind direction. The size and morphology of the Glen Torridon PBRs are consistent with transverse formative winds, but the orientation of nearby aeolian bedforms and bedrock erosional features raise the possibility of PBR formation by a net northeasterly wind regime. Although several formation models for the Glen Torridon PBRs are still under consideration, and questions persist about the nature of PBR-forming paleowinds, the presence of PBRs at this site provides important constraints on the depositional and erosional history of Gale crater.

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