Book Excerpt: \u3cem\u3eThe Guns of Normandy: A Soldier’s Eye View of France\u3c/em\u3e

Editor’s Note: Everyone who studies the land battles of the Second World War knows that artillery was the principle weapon employed by the Allied armies, but the gunners rarely receive the attention they deserve in narratives of the campaign. George Blackburn has written a book, The Guns of Normandy which restores the gunners to their rightful place. CMH is proud to publish two chapters from this book to announce that our Autumn issue will include an excerption from Mr. Blackburn’s forthcoming sequel. Chapter 15 takes up the story on 12 July 1944 as 4th Field Regiment is committed to support 4th Canadian Infantry Brigade west of Caen

Nonlinear Breit-Wheeler pair creation with bremsstrahlung γ\gamma rays

Electron-positron pairs are produced through the Breit-Wheeler process when energetic photons traverse electromagnetic fields of sufficient strength. Here we consider a possible experimental geometry for observation of pair creation in the highly nonlinear regime, in which bremsstrahlung of an ultrarelativistic electron beam in a high-$Z$ target is used to produce $\gamma$ rays that collide with a counterpropagating laser pulse. We show how the target thickness may be chosen to optimize the yield of Breit-Wheeler positrons, and verify our analytical predictions with simulations of the cascade in the material and in the laser pulse. The electron beam energy and laser intensity required are well within the capability of today's high-intensity laser facilities.Comment: 12 pages, 5 figure

Arthur Cotton and Irrigation in Tasmania, 1839-43

Cotton, an officer of the East India Company with experience of irrigation, visited Tasmania for periods totalling three years. His influence was important in gaining acceptance of irrigation as an aid to cereal production and the livestock industry. Details are given of his Tasmanian work, which had particular significance there for its emphasis on water conservation

Chemoprevention with the metabolism modifying drugs dichloroacetate and metformin in the Li-Fraumeni Syndrome model, Trp53+/- mice

BACKGROUND: While genetic testing for familial cancer has excelled, the prevention options for those carrying high risk alleles have not. Altered bioenergetics is now acknowledged as a hallmark of cancer, and several very safe drugs are available that can target this phentoype. Dichloroacetate (DCA) inactivates pyruvate dehydrogenase kinase, resulting in activation of pyruvate dehydrogenase, reduced lactic acid production and increased mitochondrial activity. Metformin, a type 2 diabetes treatment which activates AMPK, thereby inhibiting mTOR, has unambiguously been demonstrated to reduce the risk of many cancer types in diabetics. We have tested these drugs as chemopreventive agents against the mammary tumours that occur in the BALB/c-Trp53+/- mouse spontaneous tumour model. MATERIALS and METHODS Breast cancer cell lines were examined for cell viability after DCA and/or metformin treatment in vitro (neutral red uptake assay). Four groups of female BALB/c-Trp53+/- mice were given distilled water (n=75), DCA (1.5 g/L in drinking water, ~180 mg/ kg/day, n=53), metformin (0.25 g/L in drinking water, ~30 mg/kg/day, n=61) or DCA +metformin (n=51) from 8 weeks of age, and monitored for tumour development over 78 weeks, and Kaplan-Meier survival analysis was performed. RESULTS In vitro, DCA (1-5 mM) and metformin (30-300 uM), alone or combined, significantly inhibited breast cancer cell growth. In vivo, the overall tumour-free survival curves for BALB/c-Trp53+/- mice were not significantly different between treatment groups, suggesting that metformin does not reduce cancer risk in non-diabetics. However, analysis of mammary tumours alone found that DCA reduced the number and increased their latency (28.0% vs 20.8% of mice with mean latency of 55.0 vs 63.8 weeks, untreated vs DCA respectively), whereas metformin had no effect (26.2% of mice, mean latency 54.7 weeks). DCA appeared to eliminate the early onset mammary tumours (latency <52 weeks, p=0.02), while not affecting the occurrence of longer latency tumours. In contrast, the two drug combination had worse outcomes for tumour development, (35.3% of mice, latency 48.8 weeks, p<0.02 compared to DCA alone). Preliminary western blotting results in MDA-MB-468 breast cancer cells found that DCA could block the activation of AMPK by metformin, indicating the potential for drug interactions.Supported by NHMRC Career Development Award, National Breast Cancer Foundation Novel Concept Award, and Cancer Australia

Content Based Retrieval and Navigation of Music

Contents 1 Introduction ................................................... 3 2 Literature Review .............................................. 4 2.1 Navigation ............................................... 4 2.2 Navigation of audio ........................................ 4 2.3 Contentrepresentations ..................................... 5 2.3.1 The musical score ................................... 6 2.3.2 Performance data .................................... 6 2.3.3 Musical pitch contours ................................ 6 2.3.4 Alternative representations ............................ 7 2.3.5 The Fourier transform ................................ 7 2.4 Content based retrieval ..................................... 8 2.4.1 Retrieval of digital audio samples ....................... 8 2.4.2 Query by humming .................................. 8 2.4.3 Lemstrm and Laine ................................. 9 2.4.4 Image matching techni