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1.
Tech Coloproctol ; 28(1): 49, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38653930

RESUMO

BACKGROUND: Presacral tumors are a rare entity typically treated with an open surgical approach. A limited number of minimally invasive resections have been described. The aim of the study is to evaluate the safety and efficacy of roboticresection of presacral tumors. METHODS: This is a retrospective single system analysis, conducted at a quaternary referral academic healthcare system, and included all patients who underwent a robotic excision of a presacral tumor between 2015 and 2023. Outcomes of interest were operative time, estimated blood loss, complications, length of stay, margin status, and recurrence rates. RESULTS: Sixteen patients (11 females and 5 males) were included. The median age of the cohort was 51 years (range 25-69 years). The median operative time was 197 min (range 98-802 min). The median estimated blood loss was 40 ml, ranging from 0 to 1800 ml, with one patient experiencing conversion to open surgery after uncontrolled hemorrhage. Urinary retention was the only postoperative complication that occurred in three patients (19%) and was solved within 30 days in all cases. The median length of stay was one day (range 1-6 days). The median follow-up was 6.7 months (range 1-110 months). All tumors were excised with appropriate margins, but one benign and one malignant tumor recurred (12.5%). Ten tumors were classified as congenital (one was malignant), two were mesenchymal (both malignant), and five were miscellaneous (one malignant). CONCLUSIONS: Robotic resection of select presacral pathology is feasible and safe. Further studies must be conducted to determine complication rates, outcomes, and long-term safety profiles.


Assuntos
Tempo de Internação , Duração da Cirurgia , Procedimentos Cirúrgicos Robóticos , Humanos , Pessoa de Meia-Idade , Feminino , Masculino , Procedimentos Cirúrgicos Robóticos/métodos , Adulto , Idoso , Estudos Retrospectivos , Resultado do Tratamento , Tempo de Internação/estatística & dados numéricos , Margens de Excisão , Perda Sanguínea Cirúrgica/estatística & dados numéricos , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/epidemiologia , Recidiva Local de Neoplasia/cirurgia , Recidiva Local de Neoplasia/epidemiologia , Neoplasias Pélvicas/cirurgia
2.
Phys Rev E ; 109(2-2): 025204, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38491565

RESUMO

In this work we present the design of the first controlled fusion laboratory experiment to reach target gain G>1 N221204 (5 December 2022) [Phys. Rev. Lett. 132, 065102 (2024)10.1103/PhysRevLett.132.065102], performed at the National Ignition Facility, where the fusion energy produced (3.15 MJ) exceeded the amount of laser energy required to drive the target (2.05 MJ). Following the demonstration of ignition according to the Lawson criterion N210808, experiments were impacted by nonideal experimental fielding conditions, such as increased (known) target defects that seeded hydrodynamic instabilities or unintentional low-mode asymmetries from nonuniformities in the target or laser delivery, which led to reduced fusion yields less than 1 MJ. This Letter details design changes, including using an extended higher-energy laser pulse to drive a thicker high-density carbon (also known as diamond) capsule, that led to increased fusion energy output compared to N210808 as well as improved robustness for achieving high fusion energies (greater than 1 MJ) in the presence of significant low-mode asymmetries. For this design, the burnup fraction of the deuterium and tritium (DT) fuel was increased (approximately 4% fuel burnup and a target gain of approximately 1.5 compared to approximately 2% fuel burnup and target gain approximately 0.7 for N210808) as a result of increased total (DT plus capsule) areal density at maximum compression compared to N210808. Radiation-hydrodynamic simulations of this design predicted achieving target gain greater than 1 and also the magnitude of increase in fusion energy produced compared to N210808. The plasma conditions and hotspot power balance (fusion power produced vs input power and power losses) using these simulations are presented. Since the drafting of this manuscript, the results of this paper have been replicated and exceeded (N230729) in this design, together with a higher-quality diamond capsule, setting a new record of approximately 3.88MJ of fusion energy and fusion energy target gain of approximately 1.9.

3.
Nature ; 618(7964): 252-256, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37286648

RESUMO

The fast solar wind that fills the heliosphere originates from deep within regions of open magnetic field on the Sun called 'coronal holes'. The energy source responsible for accelerating the plasma is widely debated; however, there is evidence that it is ultimately magnetic in nature, with candidate mechanisms including wave heating1,2 and interchange reconnection3-5. The coronal magnetic field near the solar surface is structured on scales associated with 'supergranulation' convection cells, whereby descending flows create intense fields. The energy density in these 'network' magnetic field bundles is a candidate energy source for the wind. Here we report measurements of fast solar wind streams from the Parker Solar Probe (PSP) spacecraft6 that provide strong evidence for the interchange reconnection mechanism. We show that the supergranulation structure at the coronal base remains imprinted in the near-Sun solar wind, resulting in asymmetric patches of magnetic 'switchbacks'7,8 and bursty wind streams with power-law-like energetic ion spectra to beyond 100 keV. Computer simulations of interchange reconnection support key features of the observations, including the ion spectra. Important characteristics of interchange reconnection in the low corona are inferred from the data, including that the reconnection is collisionless and that the energy release rate is sufficient to power the fast wind. In this scenario, magnetic reconnection is continuous and the wind is driven by both the resulting plasma pressure and the radial Alfvénic flow bursts.

4.
BMC Med Res Methodol ; 22(1): 292, 2022 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-36357847

RESUMO

BACKGROUND: To report our recommended methodology for extracting and then confirming research uncertainties - areas where research has failed to answer a research question - derived from previously published literature during a broad scope Priority Setting Partnership (PSP) with the James Lind Alliance (JLA). METHODS: This process was completed in the UK as part of the PSP for "Common Conditions Affecting the Hand and Wrist", comprising of health professionals, patients and carers and reports the data (uncertainty) extraction phase of this. The PSP followed the robust methodology dictated by the JLA and sought to identify knowledge gaps, termed "uncertainties" by the JLA. Published Cochrane Systematic Reviews, Guidelines and Protocols, NICE (National Institute for Health and Care Excellence) Guidelines, and SIGN (Scottish Intercollegiate Guidelines Network) Guidelines were screened for documented "uncertainties". A robust method of screening, internally verifying and then checking uncertainties was adopted. This included independent screening and data extraction by multiple researchers and use of a PRISMA flowchart, alongside steering group consensus processes. Selection of research uncertainties was guided by the scope of the Common Conditions Affecting the Hand and Wrist PSP which focused on "common" hand conditions routinely treated by hand specialists, including hand surgeons and hand therapists limited to identifying questions concerning the results of intervention, and not the basic science or epidemiology behind disease. RESULTS: Of the 2358 records identified (after removal of duplicates) which entered the screening process, 186 records were presented to the PSP steering group for eligibility assessment; 79 were deemed within scope and included for the purpose of research uncertainty extraction (45 full Cochrane Reviews, 18 Cochrane Review protocols, 16 Guidelines). These yielded 89 research uncertainties, which were compared to the stakeholder survey, and added to the longlist where necessary; before derived uncertainties were checked against non-Cochrane published systematic reviews. CONCLUSIONS: In carrying out this work, beyond reporting on output of the Common Conditions Affecting the Hand and Wrist PSP, we detail the methodology and processes we hope can inform and facilitate the work of future PSPs and other evidence reviews, especially those with a broader scope beyond a single disease or condition.


Assuntos
Pesquisa Biomédica , Prioridades em Saúde , Humanos , Pesquisadores , Inquéritos e Questionários , Incerteza , Punho
5.
Geophys Res Lett ; 49(9): e2021GL096986, 2022 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-35864893

RESUMO

We report observations of reconnection exhausts in the Heliospheric Current Sheet (HCS) during Parker Solar Probe Encounters 08 and 07, at 16 R s and 20 R s , respectively. Heliospheric current sheet (HCS) reconnection accelerated protons to almost twice the solar wind speed and increased the proton core energy by a factor of ∼3, due to the Alfvén speed being comparable to the solar wind flow speed at these near-Sun distances. Furthermore, protons were energized to super-thermal energies. During E08, energized protons were found to have leaked out of the exhaust along separatrix field lines, appearing as field-aligned energetic proton beams in a broad region outside the HCS. Concurrent dropouts of strahl electrons, indicating disconnection from the Sun, provide further evidence for the HCS being the source of the beams. Around the HCS in E07, there were also proton beams but without electron strahl dropouts, indicating that their origin was not the local HCS reconnection exhaust.

7.
Phys Rev Lett ; 127(25): 255101, 2021 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-35029449

RESUMO

The high temperatures and strong magnetic fields of the solar corona form streams of solar wind that expand through the Solar System into interstellar space. At 09:33 UT on 28 April 2021 Parker Solar Probe entered the magnetized atmosphere of the Sun 13 million km above the photosphere, crossing below the Alfvén critical surface for five hours into plasma in casual contact with the Sun with an Alfvén Mach number of 0.79 and magnetic pressure dominating both ion and electron pressure. The spectrum of turbulence below the Alfvén critical surface is reported. Magnetic mapping suggests the region was a steady flow emerging on rapidly expanding coronal magnetic field lines lying above a pseudostreamer. The sub-Alfvénic nature of the flow may be due to suppressed magnetic reconnection at the base of the pseudostreamer, as evidenced by unusually low densities in this region and the magnetic mapping.

8.
Geophys Res Lett ; 47(20): e2020GL090115, 2020 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-33380758

RESUMO

The solar wind is slowed, deflected, and heated as it encounters Venus's induced magnetosphere. The importance of kinetic plasma processes to these interactions has not been examined in detail, due to a lack of constraining observations. In this study, kinetic-scale electric field structures are identified in the Venusian magnetosheath, including plasma double layers. The double layers may be driven by currents or mixing of inhomogeneous plasmas near the edge of the magnetosheath. Estimated double-layer spatial scales are consistent with those reported at Earth. Estimated potential drops are similar to electron temperature gradients across the bow shock. Many double layers are found in few high cadence data captures, suggesting that their amplitudes are high relative to other magnetosheath plasma waves. These are the first direct observations of plasma double layers beyond near-Earth space, supporting the idea that kinetic plasma processes are active in many space plasma environments.

9.
Leukemia ; 34(10): 2749-2753, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32594098

RESUMO

Our group previously demonstrated that M-protein light chain (LC) glycosylation can be detected on routine MASS-FIX testing. Glycosylation is increased in patients with immunoglobulin LC amyloidosis (AL) and rarely changes over the course of a patient's lifetime. To determine the rates of progression to AL and other plasma cell disorders (PCDs), we used residual serum samples from the Olmsted monoclonal gammopathy of undetermined significance (MGUS) screening cohort. Four-hundred and fourteen patients with known MGUS were tested by MASS-FIX, and 25 (6%) were found to have glycosylated LCs. With a median follow-up of surviving patients of 22.2 years, the 20-year progression rates to a malignant PCD were 67% (95% CI 29%, 84%) and 13% (95% CI 9%, 18%) for patients with and without glycosylated LCs, respectively. The risk of progression was independent of Mayo MGUS risk score. The respective rates of progression to AL at 20 years were 21% (95% CI 0.0%, 38%) and 3% (95% CI 0.6%, 5.5%). In summary, monoclonal LC glycosylation is a potent risk factor for progression to AL, myeloma, and other PCDs, an observation which could lead to earlier diagnoses and potentially reduced morbidity and mortality.


Assuntos
Biomarcadores , Cadeias Leves de Imunoglobulina/metabolismo , Gamopatia Monoclonal de Significância Indeterminada/diagnóstico , Gamopatia Monoclonal de Significância Indeterminada/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Progressão da Doença , Feminino , Glicosilação , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Gamopatia Monoclonal de Significância Indeterminada/sangue , Proteínas do Mieloma/metabolismo , Prognóstico
11.
Br J Surg ; 107(5): 560-566, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31976558

RESUMO

BACKGROUND: The aim of this study was to review risk factors for conversion in a cohort of patients with rectal cancer undergoing minimally invasive abdominal surgery. METHODS: A retrospective analysis was performed of consecutive patients operated on from February 2005 to April 2018. Adult patients undergoing low anterior resection or abdominoperineal resection for primary rectal adenocarcinoma by a minimally invasive approach were included. Exclusion criteria were lack of research authorization, stage IV or recurrent rectal cancer, and emergency surgery. Risk factors for conversion were investigated using logistic regression. A subgroup analysis of obese patients (BMI 30 kg/m2 or more) was performed. RESULTS: A total of 600 patients were included in the analysis. The overall conversion rate was 9·2 per cent. Multivariable analysis showed a 72 per cent lower risk of conversion when patients had robotic surgery (odds ratio (OR) 0·28, 95 per cent c.i. 0·15 to 0·52). Obese patients experienced a threefold higher risk of conversion compared with non-obese patients (47 versus 24·4 per cent respectively; P < 0·001). Robotic surgery was associated with a reduced risk of conversion in obese patients (OR 0·22, 0·07 to 0·71). CONCLUSION: Robotic surgery was associated with a lower risk of conversion in patients undergoing minimally invasive rectal cancer surgery, in both obese and non-obese patients.


ANTECEDENTES: El objetivo del estudio era revisar los factores de riesgo para la conversión en una cohorte de pacientes con cáncer de recto sometidos a cirugía abdominal mínimamente invasiva. MÉTODOS: Se realizó un análisis retrospectivo de pacientes consecutivos operados desde febrero de 2005 hasta abril de 2018. Se incluyeron pacientes adultos sometidos a resección anterior baja o resección abdominoperineal por adenocarcinoma primario de recto mediante abordaje mínimamente invasivo. Los criterios de exclusión fueron falta del consentimiento informado, cáncer de recto en estadio IV o recidivado y cirugía urgente. Los factores de riesgo para la conversión se determinaron mediante regresión logística. Se realizó un análisis de subgrupo en pacientes obesos (índice de masa corporal, IMC ≥ 30 kg/m2 ). RESULTADOS: Se incluyeron en el análisis un total de 600 pacientes. La tasa global de conversión fue del 9,2%. El modelo multivariado mostró un riesgo 72% menor de conversión cuando los pacientes fueron tratados mediante cirugía robótica (razón de oportunidades, odds ratio, OR 0,28, i.c. del 95% 0,15-0,52). Los pacientes obesos presentaron un riesgo de conversión tres veces mayor en comparación con los pacientes no obesos (47,3% versus 24,5%, P < 0,001). La cirugía robótica se asoció con una menor probabilidad de conversión en los pacientes obesos (OR 0,22; i.c. del 95% 0,07-0,71). CONCLUSIÓN: La cirugía robótica se asoció con un menor riesgo de conversión en pacientes sometidos a cirugía mínimamente invasiva de cáncer de recto, tanto en pacientes obesos como no obesos.


Assuntos
Adenocarcinoma/cirurgia , Conversão para Cirurgia Aberta , Laparoscopia/efeitos adversos , Neoplasias Retais/cirurgia , Procedimentos Cirúrgicos Robóticos/efeitos adversos , Adenocarcinoma/complicações , Adenocarcinoma/patologia , Adulto , Idoso , Índice de Massa Corporal , Feminino , Humanos , Complicações Intraoperatórias , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Obesidade/complicações , Neoplasias Retais/complicações , Neoplasias Retais/patologia , Reoperação , Estudos Retrospectivos , Fatores de Risco , Fatores Sexuais
12.
Br J Surg ; 107(5): 546-551, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31912500

RESUMO

BACKGROUND: This study aimed to identify patients eligible for a 48-h stay after colorectal resection, to provide guidance for early discharge planning. METHODS: A bi-institutional retrospective cohort study was undertaken of consecutive patients undergoing major elective colorectal resection for benign or malignant pathology within a comprehensive enhanced recovery pathway between 2011 and 2017. Overall and severe (Clavien-Dindo grade IIIb or above) postoperative complication and readmission rates were compared between patients who were discharged within 48 h and those who had hospital stay of 48 h or more. Multinominal logistic regression analysis was performed to ascertain significant factors associated with a short hospital stay (less than 48 h). RESULTS: In total, 686 of 5122 patients (13·4 per cent) were discharged within 48 h. Independent factors favouring a short hospital stay were age below 60 years (odds ratio (OR) 1·34; P = 0·002), ASA grade less than III (OR 1·42; P = 0·003), restrictive fluid management (less than 3000 ml on day of surgery: OR 1·46; P < 0·001), duration of surgery less than 180 min (OR 1·89; P < 0·001), minimally invasive approach (OR 1·92; P < 0·001) and wound contamination grade below III (OR 4·50; P < 0·001), whereas cancer diagnosis (OR 0·55; P < 0·001) and malnutrition (BMI below 18 kg/m2 : OR 0·42; P = 0·008) decreased the likelihood of early discharge. Patients with a 48-h stay had fewer overall (10·8 per cent versus 30·6 per cent in those with a longer stay; P < 0·001) and fewer severe (2·6 versus 10·2 per cent respectively; P < 0·001) complications, and a lower readmission rate (9·0 versus 11·8 per cent; P = 0·035). CONCLUSION: Early discharge of selected patients is safe and does not increase postoperative morbidity or readmission rates. In these patients, outpatient colorectal surgery should be feasible on a large scale with logistical optimization.


ANTECEDENTES: Este estudio tuvo como objetivo identificar pacientes candidatos para una estancia hospitalaria de 48 horas tras resecciones colónicas, con el fin de proporcionar una guía de planificación del alta precoz. MÉTODOS: Estudio de cohortes retrospectivo de pacientes consecutivos sometidos a resección colorrectal electiva mayor por patología benigna o maligna en el marco de un programa integral de recuperación intensificada (enhanced recovery pathway, ERP), de dos hospitales entre 2011 y 2017. Se compararon las tasas de complicaciones postoperatorias globales y graves (Clavien ≥ IIIb) y de reingresos entre dos grupos (< 48 horas versus ≥ 48 horas de estancia hospitalaria). Se llevó a cabo una regresión logística multinominal de factores significativos (P < 0,05) asociados con una estancia corta (< 48 horas). RESULTADOS: En total, 686/5.122 pacientes (13,4%) fueron dados de alta dentro de las primeras 48 horas. Los factores independientes que propiciaron una estancia corta fueron la edad < 60 años (razón de oportunidades, odds ratio, OR 1,34, P = 0,002), puntuación < 3 de la American Society of Anesthesiologists (ASA) (OR 1,42, P = 0,003), manejo restrictivo del aporte de líquidos (< 3000 mL en el día de la cirugía: OR 1,46, P < 0,001), duración de la cirugía < 180 minutos (OR 1,89, P < 0,001), abordaje mínimamente invasivo (OR 1,92, P < 0,001) and tipo de herida clase < 3 (OR 4,5, P < 0,001), mientras que el diagnóstico de cáncer (OR 0,55, P < 0,001) y la malnutrición (IMC < 18 kg/m2 : OR 0,42, P = 0,008) disminuyeron la probabilidad de alta precoz. Los pacientes con una estancia de 48 horas tuvieron menos complicaciones globales (10,8% versus 30,6%, P < 0,001), menos complicaciones graves (2,6% versus 10,2%, P < 0,001) y una menor tasa de reingresos (9% versus 11,8%, P = 0,035). CONCLUSIÓN: El alta precoz en pacientes seleccionados es segura y no aumenta las tasas de morbilidad postoperatoria o de reingresos. En estos pacientes, la cirugía colorrectal ambulatoria debería ser viable a gran escala con una optimización de la logística.


Assuntos
Doenças do Colo/cirurgia , Procedimentos Cirúrgicos do Sistema Digestório , Procedimentos Cirúrgicos Eletivos , Tempo de Internação , Alta do Paciente , Doenças Retais/cirurgia , Fatores Etários , Idoso , Neoplasias Colorretais/complicações , Neoplasias Colorretais/patologia , Neoplasias Colorretais/cirurgia , Procedimentos Cirúrgicos do Sistema Digestório/efeitos adversos , Procedimentos Cirúrgicos Eletivos/efeitos adversos , Feminino , Hidratação , Humanos , Masculino , Desnutrição/complicações , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Minimamente Invasivos/efeitos adversos , Gradação de Tumores , Duração da Cirurgia , Análise de Regressão , Estudos Retrospectivos , Infecção da Ferida Cirúrgica
13.
Hernia ; 24(2): 273-278, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31049717

RESUMO

PURPOSE: Though perineal hernias remain rare, the incidence is reportedly rising. Secondary to the historical rarity, optimal method of repair and outcomes after repair remain poorly understood. Therefore, we reviewed the past 25 years of our institutional experience with perineal hernia repair. METHODS: A retrospective review of an institution-maintained database was conducted from January 1, 1994 to January 31, 2018 for patients undergoing perineal hernia repair. Data were collected on patient characteristics, operative technique, and post-operative outcomes. RESULTS: Twenty-one patients (n = 12 male) underwent perineal hernia repair in the study period with two-thirds of the operations occurring in the most recent 7 years (since January 1, 2011). The median time to repair was 13 months (range 2-127) after index operation. The approach was transabdominal in nine, perineal in nine, and combined in three. Mesh, a tissue flap, or a combination of these was used in 19 of the cases and 6 additional abdominal wall hernias were repaired concurrently. Post-operative complications consisted of superficial surgical-site infection (n = 2), infected seroma (n = 1), and a missed enterotomy (n = 1). Follow-up ranged from 0 to 112 months (median 2 months) and only one recurrence was noted. CONCLUSION: Presentation for repair of perineal hernia has increased at our instituion over the past 2 decades. Outcomes did not differ between the three repair approaches and the choice of mesh or tissue-based repair. Surgeons should base these decisions on hernia complexity and local tissue conditions.


Assuntos
Herniorrafia/estatística & dados numéricos , Períneo/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Hérnia Abdominal/cirurgia , Herniorrafia/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Recidiva , Estudos Retrospectivos , Retalhos Cirúrgicos , Telas Cirúrgicas
14.
Nature ; 576(7786): 228-231, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31802006

RESUMO

The prediction of a supersonic solar wind1 was first confirmed by spacecraft near Earth2,3 and later by spacecraft at heliocentric distances as small as 62 solar radii4. These missions showed that plasma accelerates as it emerges from the corona, aided by unidentified processes that transport energy outwards from the Sun before depositing it in the wind. Alfvénic fluctuations are a promising candidate for such a process because they are seen in the corona and solar wind and contain considerable energy5-7. Magnetic tension forces the corona to co-rotate with the Sun, but any residual rotation far from the Sun reported until now has been much smaller than the amplitude of waves and deflections from interacting wind streams8. Here we report observations of solar-wind plasma at heliocentric distances of about 35 solar radii9-11, well within the distance at which stream interactions become important. We find that Alfvén waves organize into structured velocity spikes with duration of up to minutes, which are associated with propagating S-like bends in the magnetic-field lines. We detect an increasing rotational component to the flow velocity of the solar wind around the Sun, peaking at 35 to 50 kilometres per second-considerably above the amplitude of the waves. These flows exceed classical velocity predictions of a few kilometres per second, challenging models of circulation in the corona and calling into question our understanding of how stars lose angular momentum and spin down as they age12-14.

15.
Nature ; 576(7786): 237-242, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31802007

RESUMO

During the solar minimum, when the Sun is at its least active, the solar wind1,2 is observed at high latitudes as a predominantly fast (more than 500 kilometres per second), highly Alfvénic rarefied stream of plasma originating from deep within coronal holes. Closer to the ecliptic plane, the solar wind is interspersed with a more variable slow wind3 of less than 500 kilometres per second. The precise origins of the slow wind streams are less certain4; theories and observations suggest that they may originate at the tips of helmet streamers5,6, from interchange reconnection near coronal hole boundaries7,8, or within coronal holes with highly diverging magnetic fields9,10. The heating mechanism required to drive the solar wind is also unresolved, although candidate mechanisms include Alfvén-wave turbulence11,12, heating by reconnection in nanoflares13, ion cyclotron wave heating14 and acceleration by thermal gradients1. At a distance of one astronomical unit, the wind is mixed and evolved, and therefore much of the diagnostic structure of these sources and processes has been lost. Here we present observations from the Parker Solar Probe15 at 36 to 54 solar radii that show evidence of slow Alfvénic solar wind emerging from a small equatorial coronal hole. The measured magnetic field exhibits patches of large, intermittent reversals that are associated with jets of plasma and enhanced Poynting flux and that are interspersed in a smoother and less turbulent flow with a near-radial magnetic field. Furthermore, plasma-wave measurements suggest the existence of electron and ion velocity-space micro-instabilities10,16 that are associated with plasma heating and thermalization processes. Our measurements suggest that there is an impulsive mechanism associated with solar-wind energization and that micro-instabilities play a part in heating, and we provide evidence that low-latitude coronal holes are a key source of the slow solar wind.

16.
Br J Surg ; 106(7): 950-951, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31162660
17.
Tech Coloproctol ; 23(3): 259-266, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30941619

RESUMO

BACKGROUND: Minimally invasive approaches have become the standard of care for ileal pouch-anal anastomoses (IPAA). There are few reports comparing outcomes following a laparoscopic versus robotic approach. Our aim was to determine if there were any differences in the 30-day postoperative outcomes following IPAA performed laparoscopically versus robotically. METHODS: A retrospective chart review of all laparoscopic and robotic IPAA performed between January 1, 2015 and June 30, 2018 was carried out. Patients included were adult patients who underwent a proctectomy and IPAA utilizing either a laparoscopic or robotic approach. Data collected included patient demographics, operative variables, and 30-day postoperative outcomes. RESULTS: A total of 132 patients had a minimally invasive IPAA; 58 were performed laparoscopically and 74 robotically. Less than half the patients were female (n = 55; 41.7%) with a median age of 37 years (range 18-68 years). The majority of patients had a diagnosis of ulcerative colitis (n = 103; 78.0%) with medically refractory disease (n = 87; 65.9%). A greater proportion of patients in the laparoscopic cohort had a prolonged length of stay (n = 27; 46.6% versus n = 18; 24.3%; p < 0.001) and a two-stage approach (n = 56; 96.6% versus n = 37; 50%; p < 0.001), but there were no differences in the rates between the laparoscopic versus robotic cohorts of superficial surgical site infection (6.9% versus 6.8%; p = 0.99), peripouch abscess (15.5% versus 6.8%; p = 0.11), anastomotic leak (6.9% versus 2.7%; p = 0.21), pelvic abscess (15.5% versus 6.8%; p = 0.11), and pelvic sepsis (15.5% versus 6.8%; p = 0.11), readmission (24.1% versus 17.6%; p = 0.35) or reoperation (6.9% versus 5.4%; p = 0.72). On multivariable analysis, only male sex remained predictive of prolonged length of stay, and a robotic approach trended toward a decreased rate of prolonged length of stay. CONCLUSIONS: Laparoscopic and robotic IPAA have equivalent postoperative morbidity underscoring the safety of the continued expansion of the robotic platform for pouch surgery.


Assuntos
Colite Ulcerativa/cirurgia , Laparoscopia/estatística & dados numéricos , Complicações Pós-Operatórias/epidemiologia , Proctocolectomia Restauradora/métodos , Procedimentos Cirúrgicos Robóticos/estatística & dados numéricos , Adolescente , Adulto , Idoso , Feminino , Humanos , Laparoscopia/métodos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/etiologia , Estudos Retrospectivos , Procedimentos Cirúrgicos Robóticos/métodos , Resultado do Tratamento , Adulto Jovem
18.
Br J Surg ; 106(6): 692-699, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30919948

RESUMO

BACKGROUND: Transverse abdominis plane (TAP) block is considered an effective alternative to neuraxial analgesia for abdominal surgery. However, limited evidence supports its use over traditional analgesic modalities in colorectal surgery. This study compared the analgesic efficacy of liposomal bupivacaine TAP block with intrathecal (IT) opioid administration in a multicentre RCT. METHODS: Patients undergoing elective small bowel or colorectal resection were randomized to receive TAP block or a single injection of IT analgesia with hydromorphone. Patients were assessed at 4, 8, 16, 24 and 48 h after surgery. Primary outcomes were mean pain scores and morphine milligram equivalents (MMEs) administered within 48 h after surgery. Secondary outcomes included duration of hospital stay, incidence of postoperative ileus and use of intravenous patient-controlled analgesia. RESULTS: In total, 209 patients were recruited and 200 completed the trial (TAP 102, IT 98). The TAP group had a 1·6-point greater mean pain score than the IT group at 4 h after surgery, and this difference lasted for 16 h after operation. The TAP group received more MMEs within the first 24 h after surgery than the IT group (median difference in MMEs 10·0, 95 per cent c.i. 3·0 to 20·5). There were no differences in MME use at 24 and 48 h, or with respect to secondary outcomes. CONCLUSION: IT opioid administration provided better immediate postoperative pain control than TAP block. Both modalities resulted in low pain scores in patients undergoing elective colorectal surgery and should be considered in multimodal postoperative analgesic plans. Registration number: NCT02356198 ( http://www.clinicaltrials.gov).


Assuntos
Músculos Abdominais/inervação , Analgésicos Opioides/administração & dosagem , Anestésicos Locais/administração & dosagem , Bupivacaína/administração & dosagem , Hidromorfona/administração & dosagem , Bloqueio Nervoso/métodos , Dor Pós-Operatória/prevenção & controle , Idoso , Analgesia Controlada pelo Paciente , Analgésicos Opioides/uso terapêutico , Anestésicos Locais/uso terapêutico , Bupivacaína/uso terapêutico , Cirurgia Colorretal , Procedimentos Cirúrgicos Eletivos , Feminino , Humanos , Hidromorfona/uso terapêutico , Injeções Espinhais , Lipossomos , Masculino , Pessoa de Meia-Idade , Morfina/uso terapêutico , Medição da Dor , Dor Pós-Operatória/diagnóstico , Dor Pós-Operatória/tratamento farmacológico , Estudos Prospectivos , Resultado do Tratamento
19.
Space Sci Rev ; 215(1): 9, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30880847

RESUMO

With the advent of the Heliophysics/Geospace System Observatory (H/GSO), a complement of multi-spacecraft missions and ground-based observatories to study the space environment, data retrieval, analysis, and visualization of space physics data can be daunting. The Space Physics Environment Data Analysis System (SPEDAS), a grass-roots software development platform (www.spedas.org), is now officially supported by NASA Heliophysics as part of its data environment infrastructure. It serves more than a dozen space missions and ground observatories and can integrate the full complement of past and upcoming space physics missions with minimal resources, following clear, simple, and well-proven guidelines. Free, modular and configurable to the needs of individual missions, it works in both command-line (ideal for experienced users) and Graphical User Interface (GUI) mode (reducing the learning curve for first-time users). Both options have "crib-sheets," user-command sequences in ASCII format that can facilitate record-and-repeat actions, especially for complex operations and plotting. Crib-sheets enhance scientific interactions, as users can move rapidly and accurately from exchanges of technical information on data processing to efficient discussions regarding data interpretation and science. SPEDAS can readily query and ingest all International Solar Terrestrial Physics (ISTP)-compatible products from the Space Physics Data Facility (SPDF), enabling access to a vast collection of historic and current mission data. The planned incorporation of Heliophysics Application Programmer's Interface (HAPI) standards will facilitate data ingestion from distributed datasets that adhere to these standards. Although SPEDAS is currently Interactive Data Language (IDL)-based (and interfaces to Java-based tools such as Autoplot), efforts are under-way to expand it further to work with python (first as an interface tool and potentially even receiving an under-the-hood replacement). We review the SPEDAS development history, goals, and current implementation. We explain its "modes of use" with examples geared for users and outline its technical implementation and requirements with software developers in mind. We also describe SPEDAS personnel and software management, interfaces with other organizations, resources and support structure available to the community, and future development plans. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s11214-018-0576-4) contains supplementary material, which is available to authorized users.

20.
Br J Surg ; 106(7): 922-929, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30861099

RESUMO

BACKGROUND: Oncological outcomes of locally advanced rectal cancer depend on the quality of surgical and oncological management. Enhanced recovery pathways (ERPs) have yet to be assessed for their oncological impact when used in combination with minimally invasive surgery. This study assessed outcomes with or without an ERP in patients with rectal cancer. METHODS: This was a retrospective analysis of all consecutive adult patients who underwent elective minimally invasive surgery for primary rectal adenocarcinoma with curative intent between February 2005 and April 2018. Both laparoscopic and robotic procedures were included. Short-term morbidity and overall survival were compared between patients treated according to the institutional ERP and those who received conventional care. RESULTS: A total of 600 patients underwent minimally invasive surgery, of whom 320 (53·3 per cent) were treated according to the ERP and 280 (46·7 per cent) received conventional care. ERP was associated with less overall morbidity (34·7 versus 54·3 per cent; P < 0·001). Patients in the ERP group had improved overall survival on univariable (91·4 versus 81·7 per cent at 5 years; hazard ratio (HR) 0·53, 95 per cent c.i. 0·28 to 0·99) but not multivariable (HR 0·78, 0·41 to 1·50) analysis. Multivariable analysis revealed age (HR 1·46, 1·17 to 1·82), male sex (HR 1·98, 1·05 to 3·70) and complications (HR 2·23, 1·30 to 3·83) as independent risk factors for compromised overall survival. Disease-free survival was comparable for patients who had ERP or conventional treatment (80·5 versus 84·6 per cent at 5 years respectively; P = 0·272). CONCLUSION: Treatment within an ERP was associated with a lower morbidity risk that may have had a subtle impact on overall but not disease-specific survival.


Assuntos
Adenocarcinoma/cirurgia , Procedimentos Cirúrgicos Eletivos , Laparoscopia , Assistência Perioperatória/métodos , Protectomia , Neoplasias Retais/cirurgia , Procedimentos Cirúrgicos Robóticos , Adenocarcinoma/mortalidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Procedimentos Cirúrgicos Eletivos/métodos , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/prevenção & controle , Protectomia/métodos , Neoplasias Retais/mortalidade , Estudos Retrospectivos , Análise de Sobrevida , Resultado do Tratamento
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