Cosmic rays may be linked to the formation of volatiles necessary for
prebiotic chemistry. We explore the effect of cosmic rays in a
hydrogen-dominated atmosphere, as a proof-of-concept that ion-neutral chemistry
may be important for modelling hydrogen-dominated atmospheres. In order to
accomplish this, we utilize Monte Carlo cosmic ray transport models with
particle energies of $10^6$ eV $< E < 10^{12}$ eV in order to investigate the
cosmic ray enhancement of free electrons in substellar atmospheres. Ion-neutral
chemistry is then applied to a Drift-Phoenix model of a free-floating giant gas
planet. Our results suggest that the activation of ion-neutral chemistry in the
upper atmosphere significantly enhances formation rates for various species,
and we find that C$_2$H$_2$, C$_2$H$_4$, NH$_3$, C$_6$H$_6$ and possibly
C$_{10}$H are enhanced in the upper atmospheres because of cosmic rays. Our
results suggest a potential connection between cosmic ray chemistry and the
hazes observed in the upper atmospheres of various extrasolar planets.
Chemi-ionization reactions are briefly discussed, as they may enhance the
degree of ionization in the cloud layer.Comment: 22 pages, 4 figures. Accepted to the International Journal of
  Astrobiolog

C. Bilger

Ch. Helling

Miller

P. B. Rimmer

Rimmer

Skilling

English

arXiv

Granulocyte colony stimulating factor (G-CSF) was given to 17 patients with advanced breast and ovarian cancer in order to increase the intensity and effectiveness of chemotherapy. Treatment with doxorubicin, at doses of 75 mg m-2 (n = 4 patients), 100 mg m-2 (n = 5), 125 mg m-2 (n = 6) and 150 mg m-2 (n = 2), was followed by infusion of G-CSF for 11 days. G-CSF administration resulted in a return of the absolute neutrophil count to normal or above normal levels within 12-14 days at all dose levels of doxorubicin used and allowed the administration of up to three cycles of high dose chemotherapy at 14 day intervals. An absolute neutrophil count greater than 2.5 x 10(9)l-1 was not reached until day 19-21 after 75 mg m-2 of doxorubicin given without G-CSF. At doses of doxorubicin of 125 mg m-2 and 150 mg m-2 all tumours regressed rapidly, although there was marked epithelial toxicity. The overall response rate in patients with advanced breast cancer was 80% with a median time to progression of 6 months. Two months after doxorubicin-G-CSF therapy there was a pronounced improvement of symptoms compared with before treatment. Thus the effectiveness of chemotherapy may be enhanced and treatment duration shortened by the use of G-CSF infusions. Further studies of this promising approach are warranted.</p

Bronchud, M H

Howell, A

Crowther, D

Hopwood, P

Souza, L

Dexter, T M

The University of Manchester - Institutional Repository

The use of granulocyte colony-stimulating factor to increase the intensity of treatment with doxorubicin in patients with advanced breast and ovarian cancer

The authors highlight financial support of the European Community under the FP7 by an ERC starting grant.Cosmic rays may be linked to the formation of volatiles necessary for prebiotic chemistry. We explore the effect of cosmic rays in a hydrogen-dominated atmosphere, as a proof-of-concept that ion–neutral chemistry may be important for modelling hydrogen-dominated atmospheres. In order to accomplish this, we utilize Monte Carlo cosmic ray transport models with particle energies of 106 eV<E<1012 eV in order to investigate the cosmic-ray enhancement of free electrons in substellar atmospheres. Ion–neutral chemistry is then applied to a Drift–Phoenix model of a free-floating giant gas planet. Our results suggest that the activation of ion–neutral chemistry in the upper atmosphere significantly enhances formation rates for various species, and we find that C2H2, C2H4, NH3, C6H6 and possibly C10H are enhanced in the upper atmospheres because of cosmic rays. Our results suggest a potential connection between cosmic-ray chemistry and the hazes observed in the upper atmospheres of various extrasolar planets. Chemi-ionization reactions are briefly discussed, as they may enhance the degree of ionization in the cloud layer.Peer reviewe

Rimmer, P.B.

Helling, C.

Bilger, C.

St Andrews Research Repository

International Journal of Astrobiology

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The influence of galactic cosmic rays on ion-neutral hydrocarbon chemistry in the upper atmospheres of free-floating exoplanets

MH Bronchud

A Howell

D Crowther

P Hopwood

L Souza

TM Dexter

Crossref

British Journal of Cancer

AbstractCosmic rays may be linked to the formation of volatiles necessary for prebiotic chemistry. We explore the effect of cosmic rays in a hydrogen-dominated atmosphere, as a proof-of-concept that ion–neutral chemistry may be important for modelling hydrogen-dominated atmospheres. In order to accomplish this, we utilize Monte Carlo cosmic ray transport models with particle energies of 106 eV&lt;E&lt;1012 eV in order to investigate the cosmic-ray enhancement of free electrons in substellar atmospheres. Ion–neutral chemistry is then applied to a Drift–Phoenix model of a free-floating giant gas planet. Our results suggest that the activation of ion–neutral chemistry in the upper atmosphere significantly enhances formation rates for various species, and we find that C2H2, C2H4, NH3, C6H6 and possibly C10H are enhanced in the upper atmospheres because of cosmic rays. Our results suggest a potential connection between cosmic-ray chemistry and the hazes observed in the upper atmospheres of various extrasolar planets. Chemi-ionization reactions are briefly discussed, as they may enhance the degree of ionization in the cloud layer.</jats:p

The influence of galactic cosmic rays on ion–neutral hydrocarbon chemistry in the upper atmospheres of free-floating exoplanets

The Influence of Galactic Cosmic Rays on Ion-Neutral Hydrocarbon
  Chemistry in the Upper Atmospheres of Free-Floating Exoplanets

The Influence of Galactic Cosmic Rays on Ion-Neutral Hydrocarbon Chemistry in the Upper Atmospheres of Free-Floating Exoplanets

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