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1.
Opt Lett ; 42(18): 3530-3533, 2017 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-28914893

RESUMO

Applications using multi-PW lasers necessitate high temporal pulse quality with a tremendous contrast ratio (CR). The first crucial prerequisite to achieve multi-PW peak power is the generation of ultrashort pulses with good spectral phase quality. Second, to avoid any deleterious pre-ionization effect on targets, nanosecond contrast better than 1012 is also targeted. In the framework of the Apollon 10 PW French laser program, we present a high-contrast 10 fs front-end design study to inject highly energetic Ti:sapphire PW lasers. The CR has been measured and analyzed in different time ranges highlighting the different major contributions for each scale.

2.
Ann Oncol ; 26(1): 89-94, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25355723

RESUMO

BACKGROUND: To improve the therapeutic index of whole-brain radiation therapy (WBRT) in the treatment of brain metastases (BM) from breast cancer, we investigated the efficacy and safety of WBRT combined with temozolomide (TMZ) in this population. PATIENTS AND METHODS: This phase II multicenter prospective randomized study included patients with newly diagnosed intraparenchymal BMs from breast cancer, unsuitable for surgery or radiosurgery. All patients received conformal WBRT (3 Gy × 10-30 Gy), with or without concomitant TMZ administered at a dosage of 75 mg/m(2)/day during the irradiation period. The primary end point was objective response rate (ORR) 6 weeks after the end of treatment, defined as a partial or complete response on systematic brain MRI (modified WHO criteria). Secondary end points were progression-free survival (PFS) and overall survival (OS), neurologic symptoms, and tolerability. RESULTS: Between February 2008 and November 2010, 100 patients were enrolled in the study (50 in the WBRT + TMZ arm, 50 in the WBRT arm). Median age was 55 years (29-79). Median follow-up was 9.4 months [1.0-68.1]. ORRs at 6 weeks were 36% in the WBRT arm and 30% in the WBRT + TMZ arm (NS). In the WBRT arm, median PFS was 7.4 months and median OS was 11.1 months. In the WBRT + TMZ arm, median PFS was 6.9 months and median OS was 9.4 months. Treatment was well tolerated in this arm: the most common ≥grade 2 acute toxicity was reversible lymphopenia. CONCLUSION: WBRT combined with TMZ did not significantly improve local control and survival in patients with BMs from breast cancer. CLINICALTRIALS.GOV: NCT00875355.


Assuntos
Antineoplásicos Alquilantes/uso terapêutico , Neoplasias Encefálicas/radioterapia , Neoplasias da Mama/patologia , Dacarbazina/análogos & derivados , Adulto , Idoso , Neoplasias Encefálicas/secundário , Terapia Combinada , Irradiação Craniana , Dacarbazina/uso terapêutico , Intervalo Livre de Doença , Feminino , Humanos , Pessoa de Meia-Idade , Estudos Prospectivos , Temozolomida
3.
Proc Biol Sci ; 267(1442): 445-52, 2000 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-10737400

RESUMO

Bright coloration and complex visual displays are frequent and well described in many lizard families. Reflectance spectrometry which extends into the ultraviolet (UV) allows measurement of such coloration independent of our visual system. We examined the role of colour in signalling and mate choice in the agamid lizard Ctenophorus ornatus. We found that throat reflectance strongly contrasted against the granite background of the lizards' habitat. The throat may act as a signal via the head-bobbing and push-up displays of C. ornatus. Dorsal coloration provided camouflage against the granite background, particularly in females. C. ornatus was sexually dichromatic for all traits examined including throat UV reflectance which is beyond human visual perception. Female throats were highly variable in spectral reflectance and males preferred females with higher throat chroma between 370 and 400 nm. However, female throat UV chroma is strongly correlated to both throat brightness and chest UV chroma and males may choose females on a combination of these colour variables. There was no evidence that female throat or chest coloration was an indicator of female quality. However, female brightness significantly predicted a female's laying date and, thus, may signal receptivity. One function of visual display in this species appears to be intersexual signalling, resulting in male choice of females.


Assuntos
Comportamento de Escolha , Cor , Lagartos/fisiologia , Comportamento Sexual Animal/fisiologia , Raios Ultravioleta , Animais , Feminino , Masculino
4.
Mol Ecol ; 10(1): 193-203, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11251798

RESUMO

It is now evident that the genetic mating system can be very different to the observed mating system. However, it is less well known what makes particular individuals more (or less) successful than expected from the observed system. In this study the observed territorial structure of a field population of the agamid lizard, Ctenophorus ornatus, was compared with the mating system as evidenced by microsatellite parentage assignment. This study also investigated whether any male traits predicted reproductive success. Sixty-five per cent of clutches were sired at least partially by a male other than the main territory-holding male and 35% of clutches were sired by a male with no overlap of the female's territory. Multiple paternity was moderately frequent at 25% of clutches. Male chest patch size predicted territory size and the number of females in the territory, but did not predict reproductive success. Instead, male head depth and body size were independently related to the number of offspring sired. As male head depth also predicted the number of females in a territory, these males are likely to be gaining increased reproductive success as a consequence of the higher number of females in their territories. Larger body size males, however, did not have a greater number of females in their territory and instead had more extra-territorial copulations. Whether these extra-territorial copulations are due to female choice or success in male competition is unknown.


Assuntos
Genética Populacional , Lagartos/genética , Repetições de Microssatélites , Comportamento Sexual Animal , Animais , Feminino , Lagartos/fisiologia , Masculino , Análise de Regressão , Caracteres Sexuais , Territorialidade
5.
J Evol Biol ; 17(6): 1377-88, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15525422

RESUMO

The conditional evolutionarily stable strategy (ESS) with status-dependent tactics is the most commonly invoked ESS for alternative reproductive tactics within the sexes. Support for this model has recently been criticized as apparent rather than real. We address key predictions of the status-dependent ESS in three populations of the male dimorphic mite Sancassania berlesei. In S. berlesei'fighter' males are characterized by a thickened pair of legs used for killing rivals; 'scramblers' are benign. Most males in each population could be manipulated to become fighters by decreasing density, fulfilling the prediction that males make a 'decision'. There was evidence of genetic covariance between sire status and offspring morph, but also a strong effect of sire morph on offspring morph ratio. This was consistent with considerable genetic variation for the status-dependent switch point as a breeding experiment found no support for single-locus inheritance. We also found evidence that switch points evolve independently of distributions of status. This study supports the current status-dependent ESS model.


Assuntos
Acaridae/genética , Acaridae/fisiologia , Evolução Biológica , Modelos Genéticos , Fenótipo , Acaridae/anatomia & histologia , Análise de Variância , Animais , Peso Corporal , Larva/anatomia & histologia , Larva/fisiologia , Modelos Lineares , Modelos Logísticos , Masculino , Densidade Demográfica , Escócia , Comportamento Sexual Animal/fisiologia
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