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The Double Asteroid Redirection Test (DART) had an impact with Dimorphos (a satellite of the asteroid Didymos) on 26 September 20221. Ground-based observations showed that the Didymos system brightened by a factor of 8.3 after the impact because of ejecta, returning to the pre-impact brightness 23.7 days afterwards2. Hubble Space Telescope observations made from 15 minutes after impact to 18.5 days after, with a spatial resolution of 2.1 kilometres per pixel, showed a complex evolution of the ejecta3, consistent with other asteroid impact events. The momentum enhancement factor, determined using the measured binary period change4, ranges between 2.2 and 4.9, depending on the assumptions about the mass and density of Dimorphos5. Here we report observations from the LUKE and LEIA instruments on the LICIACube cube satellite, which was deployed 15 days in advance of the impact of DART. Data were taken from 71 seconds before the impact until 320 seconds afterwards. The ejecta plume was a cone with an aperture angle of 140 ± 4 degrees. The inner region of the plume was blue, becoming redder with increasing distance from Dimorphos. The ejecta plume exhibited a complex and inhomogeneous structure, characterized by filaments, dust grains and single or clustered boulders. The ejecta velocities ranged from a few tens of metres per second to about 500 metres per second.
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BACKGROUND: Hyperthermic intraperitoneal chemotherapy (HIPEC) is advised as a treatment option for epithelial ovarian cancer (EOC) with peritoneal carcinomatosis. This study was designed to define the pharmacokinetics of cisplatin (CDDP) and paclitaxel (PTX) administered together during HIPEC. METHODS: Thirteen women with EOC underwent cytoreductive surgery (CRS) and HIPEC, with CDDP and PTX. Blood, peritoneal perfusate and tissue samples were harvested to determine drug exposure by high-performance liquid chromatography and matrix-assisted laser desorption ionization imaging mass spectrometry (IMS). RESULTS: The mean maximum concentrations of CDDP and PTX in perfusate were, respectively, 24.8±10.4 µg ml(-1) and 69.8±14.3 µg ml(-1); in plasma were 1.87±0.4 µg ml(-1) and 0.055±0.009 µg ml(-1). The mean concentrations of CDDP and PTX in peritoneum at the end of HIPEC were 23.3±8.0 µg g(-1) and 30.1±18.3 µg(-1)g(-1), respectively. The penetration of PTX into the peritoneal wall, determined by IMS, was about 0.5 mm. Grade 3-4 surgical complications were recorded in four patients, five patients presented grade 3 and two patients presented grade 4 hematological complications. CONCLUSIONS: HIPEC with CDDP and PTX after CRS is feasible with acceptable morbidity and has a favorable pharmacokinetic profile: high drug concentrations are achieved in peritoneal tissue with low systemic exposure. Larger studies are needed to demonstrate its efficacy in patients with microscopic postsurgical residual tumours in the peritoneal cavity.
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Protocolos de Quimioterapia Combinada Antineoplásica/farmacocinética , Carcinoma/tratamento farmacológico , Neoplasias Epiteliais e Glandulares/tratamento farmacológico , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Peritoneais/tratamento farmacológico , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Área Sob a Curva , Carcinoma/secundário , Cisplatino/administração & dosagem , Feminino , Humanos , Hipertermia Induzida , Infusões Parenterais , Masculino , Pessoa de Meia-Idade , Neoplasias Epiteliais e Glandulares/secundário , Neoplasias Ovarianas/patologia , Paclitaxel/administração & dosagem , Neoplasias Peritoneais/secundário , Peritônio/metabolismoRESUMO
Binary homopolymer blends of two hydroxyl-terminated polystyrene (PS-OH) and polymethylmethacrylate (PMMA-OH) homopolymers (Mn â¼ 16000 g mol(-1)) were grafted on SiO2 substrates by high-temperature (T > 150 °C), short-time (t < 600 s) thermal treatments. The resulting brush layer was tested to screen preferential interactions of the SiO2 substrate with the different symmetric and asymmetric PS-b-PMMA block copolymers deposited on top of the grafted molecules. By properly adjusting the blend composition and the processing parameters, an efficient surface neutralization path was identified, enabling the formation, in the block copolymer film, of homogeneous textures of lamellae or cylinders perpendicularly oriented with respect to the substrate. A critical interplay between the phase segregation of the homopolymer blends and their grafting process on the SiO2 was observed. In fact, the polar SiO2 is preferential for the PMMA-rich phase that forms a homogeneous layer on the substrate, while the PS-rich phase is located at the polymer-air interface. During the thermal treatment, phase segregation and grafting proceed simultaneously. Complete wetting of the PS rich phase on the PMMA rich phase leads to the formation of a PS/PMMA bilayer. In this case, the progressive diffusion of PS chains toward the polymer-SiO2 interface during the thermal treatment allows tuning of the brush layer composition.
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Spacecraft observations revealed that rocks on carbonaceous asteroids, which constitute the most numerous class by composition, can develop millimeter-to-meter-scale fractures due to thermal stresses. However, signatures of this process on the second-most populous group of asteroids, the S-complex, have been poorly constrained. Here, we report observations of boulders' fractures on Dimorphos, which is the moonlet of the S-complex asteroid (65803) Didymos, the target of NASA's Double Asteroid Redirection Test (DART) planetary defense mission. We show that the size-frequency distribution and orientation of the mapped fractures are consistent with formation through thermal fatigue. The fractures' preferential orientation supports that these have originated in situ on Dimorphos boulders and not on Didymos boulders later transferred to Dimorphos. Based on our model of the fracture propagation, we propose that thermal fatigue on rocks exposed on the surface of S-type asteroids can form shallow, horizontally propagating fractures in much shorter timescales (100 kyr) than in the direction normal to the boulder surface (order of Myrs). The presence of boulder fields affected by thermal fracturing on near-Earth asteroid surfaces may contribute to an enhancement in the ejected mass and momentum from kinetic impactors when deflecting asteroids.
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Self-assembling block copolymers generate nanostructured patterns which are useful for a wide range of applications. In this paper we demonstrate the capability to control the morphology of the self-assembling process of PS-b-PMMA diblock copolymer thin films on unpatterned surfaces by means of fast thermal treatment performed in a rapid thermal processing machine. The methodology involves the use of radiation sources in order to rapidly drive the polymeric film above the glass transition temperature. Highly ordered patterns were obtained for perpendicular-oriented cylindrical and lamellar PS-b-PMMA block copolymers in less than 60 s. This approach offers the unprecedented opportunity to investigate in detail the kinetics of the block copolymer self-assembly during the early stages of the process, providing a much deeper understanding of the chemical and physical phenomena governing these processes.
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PURPOSE: The incidence of inguinal hernia is higher in elderly because of aging-related diseases like prostatism, bronchitis, collagen laxity. A conservative management is common in elderly to reduce surgery-related risks, however watchful waiting can expose to obstruction and strangulation. The aim of the present study was to assess the impact of emergency surgery in a large series of elderly with complicated groin hernia and to identify the independent risk factors for postoperative morbidity and mortality. The predictive performance of prognostic risk scores has been also assessed. METHODS: This is a prospective observational study carried out between January 2017 and June 2018 in elderly patients who underwent emergency surgery for complicated hernia in 38 Italian hospitals. Pre-operative, surgical and postoperative data were recorded for each patient. ASA score, Charlson's comorbidity index, P-POSSUM and CR-POSSUM were assessed. RESULTS: 259 patients were recruited, mean age was 80 years. A direct repair without mesh was performed in 62 (23.9%) patients. Explorative laparotomy was performed in 56 (21.6%) patients and bowel resection was necessary in 44 (17%). Mortality occurred in seven (2.8%) patients. Fifty-five (21.2%) patients developed complications, 12 of whom had a major one. At univariate and multivariate analyses, Charlson's comorbidity index ≥ 6, altered mental status, and need for laparotomy were associated with major complications and mortality CONCLUSION: Emergency surgery for complicated hernia is burdened by high morbidity and mortality in elderly patients. Preoperative comorbidity played a pivotal role in predicting complications and mortality and therefore Charlson's comorbidity index could be adopted to select patients for elective operation.
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Hérnia Femoral , Hérnia Inguinal , Idoso , Idoso de 80 Anos ou mais , Hérnia Femoral/cirurgia , Hérnia Inguinal/complicações , Herniorrafia/efeitos adversos , Humanos , Morbidade , Análise Multivariada , Complicações Pós-Operatórias/etiologia , Sistema de Registros , Estudos RetrospectivosRESUMO
INTRODUCTION: Centralization of trauma patients has become the standard of care. Unfortunately, overtriage can overcome the capability of Trauma Centres. This study aims to analyse the association of different mechanisms of injury with severe or major trauma defined as Injury Severity Score (ISS) greater than 15 and an estimation of overtriage upon our Trauma Centre. METHODS: A retrospective review of our prospective database was undertaken from March 2014 to August 2016. Univariate and multivariable logistic regression models were used to estimate the association between covariates (gender, age, and mechanisms of injury) and the risk of major trauma. RESULTS: The trauma team (TT) treated 1575 patients: among the 1359 (86%) were triaged only because of dynamics or mechanism of trauma. Overtriage according to an ISS < 15, was 74.6% on all trauma team activation (TTA) and 83.2% among the TTA prompted by the mechanism of injury. Patients aged 56-70 years had an 87% higher risk of having a major trauma than younger patients (OR 1.87, 95% CI 1.29-2.71) while for patients aged more than 71 years OR was 3.45, 95% CI 2.31-5.15. Car head-on collision (OR 2.50, 95% CI 1.27-4.92), intentional falls (OR 5.61, 95% CI 2.43-12.97), motorbike crash (OR 1.67, 95% CI 1.06-2.65) and pedestrian impact (OR 2.68, 95% CI 1.51-4.74) were significantly associated with a higher risk of major trauma in a multivariate analysis. CONCLUSIONS: Significant association with major trauma was demonstrated in the multivariate analysis of different mechanisms of trauma in patients triaged only for dynamics. A revision of our field triage protocol with a prospective validation is needed to improve overtriage that is above the suggested limits.
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Acidentes por Quedas , Acidentes de Trânsito , Serviços Centralizados no Hospital , Centros de Traumatologia , Triagem , Ferimentos e Lesões/terapia , Adolescente , Adulto , Idoso , Serviços Médicos de Emergência , Feminino , Humanos , Escala de Gravidade do Ferimento , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Razão de Chances , Pedestres , Estudos Retrospectivos , Tentativa de Suicídio , Adulto JovemRESUMO
[This corrects the article DOI: 10.1186/s13017-017-0141-6.].
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INTRODUCTION: The most common cause of tumour progression in advanced gastric cancer is peritoneal carcinosis (PC). The necessity to increase the survival in advanced diseases suggested to deliver the chemotherapy directly in the peritoneal cavity also in Cy+/PC- and to experiment the effect of massive peritoneal lavage to wash out the tumour cells. The aim of this study is to investigate the gain in term of survival and peritoneal recurrence rate of the intraperitoneal chemotherapy and/or peritoneal lavage in patients with Cy+/PC-. MATERIAL AND METHODS: A systematic review with meta-analysis of trials about the effect of intraperitoneal chemotherapy (IPC) and/or peritoneal lavage (PL) on positive cytology in gastric cancer without carcinosis. RESULTS: Three trials have been included (164 patients: 76 received surgery alone, 51 surgery + IPC and 37 surgery + IPC + PL). Two- and five-years survival is increased by IPC (RR = 1.62, RR = 3.10). 2 and 5 years survival is further increased by IPC + PL (RR = 2.33, RR = 6.19). Peritoneal recurrence is reduced by IPC (OR = 0.45) and by IPC + PL (OR = 0.13). CONCLUSIONS: Two- and five-years overall survival in patients with free cancer cells without carcinosis is incremented by intraperitoneal chemotherapy. Peritoneal lavage further increases these survival rates and also it further decreases the peritoneal recurrence rate.
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Antineoplásicos/uso terapêutico , Carcinoma/terapia , Lavagem Peritoneal/métodos , Neoplasias Peritoneais/terapia , Neoplasias Gástricas/terapia , Carcinoma/secundário , Humanos , Infusões Parenterais , Cavidade Peritoneal , Neoplasias Peritoneais/secundário , Prognóstico , Neoplasias Gástricas/patologia , Taxa de Sobrevida , Irrigação Terapêutica/métodosRESUMO
Acute calculus cholecystitis is a very common disease with several area of uncertainty. The World Society of Emergency Surgery developed extensive guidelines in order to cover grey areas. The diagnostic criteria, the antimicrobial therapy, the evaluation of associated common bile duct stones, the identification of "high risk" patients, the surgical timing, the type of surgery, and the alternatives to surgery are discussed. Moreover the algorithm is proposed: as soon as diagnosis is made and after the evaluation of choledocholitiasis risk, laparoscopic cholecystectomy should be offered to all patients exception of those with high risk of morbidity or mortality. These Guidelines must be considered as an adjunctive tool for decision but they are not substitute of the clinical judgement for the individual patient.
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[This corrects the article DOI: 10.1186/s13017-016-0082-5.].
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INTRODUCTION: Systemic response to cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) causes the activation of endocrine, metabolic, hemodynamic and inflammatory processes. The aim of this work is to describe and analyze the time course of the inflammatory markers concentration during CRS+HIPEC in plasma and peritoneal fluids and the association with hemodynamic and metabolic parameters. MATERIAL AND METHODS: Pre-, Intra- and Post-operative data were collected. Tumor necrosis factor (TNF), interleukine 6, procalcitonine (PCT), cancer antigen 125 (CA-125) in blood and in peritoneal fluids were evaluated. RESULTS: Thirty-eight patients included, 29 (76.3%) female. Mean/median PCI: 9.2/5. Primary malignancy: 5 colo-rectal (13.2%), 5 gastric (13.2%), 23 ovarian (60.5%) and 5 others (13.2%). CCR 0-1 reached in all patients. Cardiac Index, Heart rate and Central Venous Pressure, increased during the procedure while Stroke Volume Variation showed a decrease. Mean Arterial Pressure and Superior Vena Cava Oxygenation were stable through the whole procedure. TNF and CA-125 were steady during the whole procedure; IL-6 had a relevant increase from baseline to start of perfusion (p<0.01); PCT had a steady increase at every time point. Peritoneal sampling showed a statistically significant increase (p<0.01) between start and end of the perfusion phase for all markers but TNF. Serum and peritoneal marker concentration were similar for TNF, PCT and CA-125. IL-6 showed a sharp difference. CONCLUSION: The most significant variations are those of IL-6 and PCT. The cytokines level parallel the hemodynamic derangements. Treatment during HIPEC should mimic the established treatment during sepsis and septic shock.