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1.
Eur Phys J E Soft Matter ; 44(4): 52, 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33856559

RESUMO

Artists, using empirical knowledge, manage to generate and play with giant soap films and bubbles. Until now, scientific studies of soap films generated at a controlled velocity and without any feeding from the top, studied films of a few square centimeters. The present work aims to present a new setup to generate and characterize giant soap films (2 m [Formula: see text] 0.7 m). Our setup is enclosed in a humidity-controlled box of 2.2 m high, 1 m long, and 0.75 m large. Soap films are entrained by a fishing line withdrawn out of a bubbling solution at various velocities. We measure the maximum height of the generated soap films, as well as their lifetime, thanks to automatic detection. This is allowed by light-sensitive resistors collecting the light reflected on the soap films and ensures robust statistical measurements. In the meantime, thickness measurements are performed with a UV-VIS-spectrometer, allowing us to map the soap film's thickness over time.

2.
Turk J Gastroenterol ; 31(10): 695-705, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-33169707

RESUMO

BACKGROUND/AIMS: The Bretagne-Pays de la Loire cancer observatory, an oncology network created by the French Ministry of Health, is specifically dedicated to assess the use of new targeted anticancer therapies in routine practice. In line with the French National Cancer III program, our cancer network set up a real-life cohort, which is independent of the pharmaceutical industry, for patients with colorectal cancer to monitor patient safety and quality of care and promote pharmacovigilance. MATERIALS AND METHODS: Panitumumab monotherapy was assessed in 243 patients with wild-type Kirsten rat sarcoma who were treated for metastatic colorectal cancer (mCRC) between July 2008 and December 2010 after prior chemotherapy using oxaliplatine and irinotecan. This was a post-European medicine agency marketing (EMA-M) study Results: This study shed light on the best practices, strategic adaptations, clinical results (treatment objective responses, 13%; progression free survival, 2.99 months [2.73-3.15]; and overall survival, 6.8 months [5.49-8.38]) as well as expected or unexpected (grade 3 or 4: 11.5%) secondary effects in the phase IV panitumumab treatment of mCRC. CONCLUSION: Our results are similar to those by Amado whose phase III study led to obtaining EMA-M for panitumumab and tend to confirm the antitumor activity of this antiepidermal growth factor receptor antibody in the treatment of mCRC. In addition, our results opened avenues to further assessment of panitumumab use as monotherapy as well as its benefit-risk ratio while taking into account the patients' general and clinical characteristics. In 2012, the French National Authority for Health appended these data to the panitumumab transparency committee report.


Assuntos
Antineoplásicos Imunológicos/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico , Panitumumabe/uso terapêutico , Vigilância de Produtos Comercializados , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Colorretais/genética , Feminino , França , Geriatria , Humanos , Masculino , Oncologia , Pessoa de Meia-Idade , Intervalo Livre de Progressão , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Resultado do Tratamento
3.
Sci Rep ; 9(1): 1698, 2019 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-30737460

RESUMO

Recent paleoclimatic studies suggest that changes in the tropical rainbelt across the Atlantic Ocean during the past two millennia are linked to a latitudinal shift of the Intertropical Convergence Zone (ITCZ) driven by the Northern Hemisphere (NH) climate. However, little is known regarding other potential drivers that can affect tropical Atlantic rainfall, mainly due to the scarcity of adequate and high-resolution records. In this study, we fill this gap by reconstructing precipitation changes in Northeastern Brazil during the last 2,300 years from a high-resolution lake record of hydrogen isotope compositions of plant waxes. We find that regional precipitation along the coastal area of South America was not solely governed by north-south displacements of the ITCZ due to changes in NH climate, but also by the contraction and expansion of the tropical rainbelt due to variations in sea surface temperature and southeast trade winds in the tropical South Atlantic Basin.

4.
Sci Rep ; 7(1): 13626, 2017 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-29051588

RESUMO

The early 2000s accelerated ice-mass loss from large outlet glaciers in W and SE Greenland has been linked to warming of the subpolar North Atlantic. To investigate the uniqueness of this event, we extend the record of glacier and ocean changes back 1700 years by analyzing a sediment core from Sermilik Fjord near Helheim Glacier in SE Greenland. We show that multidecadal to centennial increases in alkenone-inferred Atlantic Water SSTs on the shelf occurred at times of reduced solar activity during the Little Ice Age, when the subpolar gyre weakened and shifted westward promoted by atmospheric blocking events. Helheim Glacier responded to many of these episodes with increased calving, but despite earlier multidecadal warming episodes matching the 20th century high SSTs in magnitude, the glacier behaved differently during the 20th century. We suggest the presence of a floating ice tongue since at least 300 AD lasting until 1900 AD followed by elevated 20th century glacier calving due to the loss of the tongue. We attribute this regime shift to 20th century unprecedented low sea-ice occurrence in the East Greenland Current and conclude that properties of this current are important for the stability of the present ice tongues in NE Greenland.

5.
NPJ Microgravity ; 1: 15004, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-28725710

RESUMO

Antifoams are widely used to control or to avoid foam production. In order to work, antifoam particles need to break foam films efficiently, which many antifoams do very well. However, once they have broken a film, to continue to be effective they need to be transported to the next film. We show, for the first time, that buoyancy has an important part in the transport of the antifoam particles. In microgravity, where buoyancy and gravitational drainage are strongly slowed down, diffusion leads to poor antifoam performance. The foam is stable for the duration of the experiment, whereas on Earth the foam starts to disappear immediately. Indeed, microgravity renders highly efficient antifoam practically useless.

6.
Lancet Oncol ; 15(2): 184-90, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24440473

RESUMO

BACKGROUND: EORTC trial 22921 examined the addition of preoperative or postoperative chemotherapy to preoperative radiotherapy in patients with rectal cancer. After a median follow-up of 5 years, chemotherapy-irrespective of timing-significantly improved local control. Adjuvant chemotherapy did not improve survival, but the Kaplan-Meier curves diverged, suggesting possible delayed benefit. Here, we report the updated long-term results. METHODS: We randomly assigned patients with clinical stage T3 or T4 resectable rectal cancer to receive preoperative radiotherapy with or without concomitant chemotherapy before surgery followed by either adjuvant chemotherapy or surveillance. Randomisation was done using minimisation with factors of institution, sex, T stage, and distance from the tumour to the anal verge. Study coordinators, clinicians, and patients were aware of assignment. Radiotherapy consisted of 45 Gy to the posterior pelvis in 25 fractions of 1·8 Gy over 5 weeks. Each course of chemotherapy consisted of fluorouracil (350 mg/m(2) per day intravenous bolus) and folinic acid (leucovorin; 20 mg/m(2) per day intravenous bolus). For preoperative chemotherapy, two courses were given (during weeks 1 and 5 of radiotherapy). Adjuvant chemotherapy was given in four cycles, every 3 weeks. The primary endpoint was overall survival. This analysis was done by intention to treat. The trial is registered with ClinicalTrials.gov, number NCT00002523. FINDINGS: 1011 patients were randomly assigned to treatment between April, 1993, and March, 2003 (252 to preoperative radiotherapy and 253 to each of the other three groups). After a median follow-up of 10·4 years (IQR 7·8-13·1), 10-year overall survival was 49·4% (95% CI 44·6-54·1) for the preoperative radiotherapy group and 50·7% (45·9-55·2) for the preoperative radiotherapy and chemotherapy group (HR 0·99, 95% CI 0·83-1·18; p=0·91). 10-year overall survival was 51·8% (95% CI 47·0-56·4) for the adjuvant chemotherapy group and 48·4% (43·6-53·0) for the surveillance group (HR 0·91, 95% CI 0·77-1·09, p=0·32). 10-year disease-free survival was 44·2% (95% CI 39·5-48·8) for the preoperative radiotherapy group and 46·4% (41·7-50·9) for the preoperative radiotherapy and chemotherapy group (HR 0·93, 95% CI 0·79-1·10; p=0·38). 10-year disease-free survival was 47·0% (95% CI 42·2-51·6) for the adjuvant chemotherapy group and 43·7% (39·1-48·2) for the surveillance group (HR 0·91, 95% CI 0·77-1·08, p=0·29). At 10 years, cumulative incidence of local relapse was 22·4% (95% CI 17·1-27·6) with radiotherapy alone, 11·8% (7·8-15·8) with neoadjuvant radiotherapy and chemotherapy, 14·5% (10·1-18·9) with radiotherapy and adjuvant chemotherapy and 11·7% (7·7-15·6) with both adjuvant and neoadjuvant chemotherapy (p=0·0017). There was no difference in cumulative incidence of distant metastases (p=0·52). The frequency of long-term side-effects did not differ between the four groups (p=0·22). INTERPRETATION: Adjuvant fluorouracil-based chemotherapy after preoperative radiotherapy (with or without chemotherapy) does not affect disease-free survival or overall survival. Our trial does not support the current practice of adjuvant chemotherapy after preoperative radiotherapy with or without chemotherapy. New treatment strategies incorporating neoadjuvant chemotherapy are required. FUNDING: EORTC, US National Cancer Institute, Programme Hospitalier de Recherche Clinique, Ligue contre le Cancer Comité du Doubs.


Assuntos
Adenocarcinoma/terapia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Quimiorradioterapia Adjuvante , Procedimentos Cirúrgicos do Sistema Digestório , Terapia Neoadjuvante , Neoplasias Retais/terapia , Adenocarcinoma/mortalidade , Adenocarcinoma/patologia , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Quimiorradioterapia Adjuvante/efeitos adversos , Quimiorradioterapia Adjuvante/mortalidade , Quimioterapia Adjuvante , Procedimentos Cirúrgicos do Sistema Digestório/efeitos adversos , Procedimentos Cirúrgicos do Sistema Digestório/mortalidade , Progressão da Doença , Intervalo Livre de Doença , Europa (Continente) , Feminino , Fluoruracila/administração & dosagem , Humanos , Análise de Intenção de Tratamento , Israel , Estimativa de Kaplan-Meier , Leucovorina/administração & dosagem , Masculino , Pessoa de Meia-Idade , Terapia Neoadjuvante/efeitos adversos , Terapia Neoadjuvante/mortalidade , Estadiamento de Neoplasias , Modelos de Riscos Proporcionais , Neoplasias Retais/mortalidade , Neoplasias Retais/patologia , Fatores de Risco , Taxa de Sobrevida , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
7.
PLoS One ; 8(2): e56504, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23418580

RESUMO

The structure, functioning and dynamics of polar marine ecosystems are strongly influenced by the extent of sea ice. Ice algae and pelagic phytoplankton represent the primary sources of nutrition for higher trophic-level organisms in seasonally ice-covered areas, but their relative contributions to polar marine consumers remain largely unexplored. Here, we investigated the potential of diatom-specific lipid markers and highly branched isoprenoids (HBIs) for estimating the importance of these two carbon pools in an Antarctic pelagic ecosystem. Using GC-MS analysis, we studied HBI biomarkers in key marine species over three years in Adélie Land, Antarctica: euphausiids (ice krill Euphausia crystallorophias and Antarctic krill E. superba), fish (bald notothens Pagothenia borchgrevinki and Antarctic silverfish Pleuragramma antarcticum) and seabirds (Adélie penguins Pygoscelis adeliae, snow petrels Pagodroma nivea and cape petrels Daption capense). This study provides the first evidence of the incorporation of HBI lipids in Antarctic pelagic consumers. Specifically, a di-unsaturated HBI (diene) of sea ice origin was more abundant in ice-associated species than in pelagic species, whereas a tri-unsaturated HBI (triene) of phytoplanktonic origin was more abundant in pelagic species than in ice-associated species. Moreover, the relative abundances of diene and triene in seabird tissues and eggs were higher during a year of good sea ice conditions than in a year of poor ice conditions. In turn, the higher contribution of ice algal derived organic matter to the diet of seabirds was related to earlier breeding and higher breeding success. HBI biomarkers are a promising tool for estimating the contribution of organic matter derived from ice algae in pelagic consumers from Antarctica.


Assuntos
Biomarcadores/análise , Diatomáceas/química , Cadeia Alimentar , Terpenos/análise , Animais , Regiões Antárticas , Aves/metabolismo , Ecossistema , Euphausiacea/química , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Geografia , Camada de Gelo , Masculino , Biologia Marinha , Perciformes/metabolismo , Fitoplâncton/química , Spheniscidae/metabolismo , Terpenos/química
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