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We convert a GeV laser-plasma electron accelerator into a compact femtosecond-pulsed $\gamma$-ray source by inserting a $100 \mu$m-thick glass plate $\sim3$ cm after the accelerator exit. With near-unity reliability, and requiring only crude alignment, this glass plasma mirror retro-reflected spent drive laser pulses (photon energy $\hbar\omega_L = 1.17$ eV) with $>50\%$ efficiency back onto trailing electrons (peak Lorentz factor $1000 < \gamma_e < 4400$), creating an optical undulator that generated $\sim10^8 \gamma$-ray photons with sub-mrad divergence, estimated peak brilliance $\sim10^{21}$ photons/s/mm$^2$/mrad$^2$/$0.1\%$ bandwidth and negligible bremsstrahlung background. The $\gamma$-ray photon energy $E_\gamma = 4\gamma_e^2 \hbar\omega_L$, inferred from the measured $\gamma_e$ on each shot, peaked from 5 to 85 MeV, spanning a range otherwise available with comparable brilliance only from large-scale GeV-linac-based high-intensity $\gamma$-ray sources.

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BACKGROUND: This study evaluated the incidence of rebleeding and death at 6 weeks after a first episode of acute variceal haemorrhage (AVH) treated by emergency endoscopic sclerotherapy in a large cohort of alcoholic cirrhotic patients. METHODS: From January 1984 to December 2006, 310 alcoholic cirrhotic patients (242 men, 68 women; mean age 51.7 years) with AVH underwent 786 endoscopic variceal injection treatments (342 emergency, 444 elective) during 919 endoscopy sessions in the first 6 weeks after the first variceal bleed. Endoscopic control of initial bleeding, variceal rebleeding and survival at 6 weeks were recorded. RESULTS: Endoscopic intervention controlled AVH in 304 of 310 patients (98.1%). Seventy-five patients (24.2%) rebled, 38 (12.3%) within 5 days and 37 (11.9%) within 6 weeks. No patient scored as Child-Pugh A died. Seventy-seven (24.8%) Child-Pugh B and C patients died, 29 (9.3%) within 5 days and 48 (15.4%) between 6 and 42 days. Mortality increased exponentially as the Child-Pugh score increased, reaching 80% when the score exceeded 13. CONCLUSION: Despite initial control of variceal haemorrhage, 1 in 4 patients (24.2%) rebled within 6 weeks. Survival at 6 weeks was 75.2% and was influenced by the severity of liver failure, with most deaths occurring in Child-Pugh grade C patients.