Two Days of My Six Year War: 9–10 July 1944

Early in July I was called back to Battery H.Q. and briefed on Operation “Charnwood,” after which I went back to the troop and told the sergeants who in turn gave the information to the crews so that everyone knew what was intended and could carry on should he end up as senior man. The gist of the briefing was that an attack was to start by the English on our left at 0700 hours and would proceed south through Buron, Gruchy and Authie just north of Carpiquet airport by mid-morning, after which the Canadian 9th Brigade on the left and the 7th Brigade on the right would move east through their ground and drive to Caen. General FU with whom the division was very familiar and who had a large part in our training in England, was very much in evidence. The English advance was held up and 9th Brigade, according to my notes, moved in and took the villages and 7th Brigade went east to the Abbaye Ardenne and Caen. My recollection of one 48-hour period with the most action of any is as follows

Inter-correlations between laboratory Inter-correlations between laboratory and field-based tests of muscle contractile power

International Journal of Exercise Science 9(5): 635-645, 2016. Muscle contractile properties have previously been distinguished by fiber typing muscle samples obtained from needle biopsy; however due to conflicting evidence regarding sampling bias and the related need for multiple biopsies, it is not certain if these results are a reliable reflection of whole muscle fiber type expression. Inter-correlations between laboratory and field-based measures of muscle contractile power were used to determine which assessments best discriminate between participants of varying sprint performance, and indirectly reveal potential for power vs. endurance exercise performance. Healthy active male (n=32) and female (n=17) participants were recruited from the Central West region of New South Wales. Isometric rate of force development (RFD) and isokinetic torque were assessed at different velocities. A counter movement jump (CMJ) test was implemented to assess concentric and eccentric RFD. A modified Wingate test was used to assess peak power expressed as Watts using a stationary start to the onset of decreased cadence. A 20m sprint was used as a field-based measurement of exercise performance, recording split times at 2m, 10m and 20m, and interval times from 2-10m, 2-20m, and 10-20m. Over 85% (r2=0.851) of 10-20m sprint running performance variance was significantly accounted for by a multiple regression model consisting of peak Watts per kilogram body mass during the modified Wingate (pkWkg), sex, and peak concentric rate of force development (pkcRFDkg). Results indicate a highly significant and predictive relationship between performance measures assessed by the modified Wingate test and sprint running performance in both males and females. Laboratory power tests alone seem sensitive enough to ascertain suitability for power vs. endurance performance potential

Hidden momentum of electrons, nuclei, atoms and molecules

We consider the positions and velocities of electrons and spinning nuclei and demonstrate that these particles harbour hidden momentum when located in an electromagnetic field. This hidden momentum is present in all atoms and molecules, however it is ultimately cancelled by the momentum of the electromagnetic field. We point out that an electron vortex in an electric field might harbour a comparatively large hidden momentum and recognise the phenomenon of 'hidden hidden momentum'

Influence of the rod photoresponse on light adaptation and circadian rhythmicity in the cone ERG

Purpose: In the mammalian retina, rod and cone pathways are fundamentally intertwined, with signals from both converging on cone bipolar cells to reach retinal ganglion cells. Psychophysical and electrophysiological data suggests that, as a consequence, rod signal transduction has a suppressive effect on the activity of cone pathways. It therefore might be assumed that the balance between rod and cone input to cone bipolar cells would be subject to dynamic regulation. There is evidence of light and time-of-day dependent alterations in this parameter. Here we set out to determine the extent to which such changes in rod-cone pathway convergence explain alterations in cone pathway function associated with light adaptation and circadian phase by recording cone electroretinograms (ERGs) in mice deficient in rod phototransduction. Methods: Cone-isolated ERGs elicited by bright flashes superimposed on a rod saturating background light were recorded from wild-type and rod transducin deficient (Gnat1−/−) mice. The process of light adaptation was observed by tracing changes in the ERG waveform over 20 min exposure to the background light in these genotypes, and circadian control by comparing responses at subjective midday and midnight. Results: The cone ERG b-wave exhibited significantly enhanced amplitude and reduced latency (implicit time) in Gnat1−/− mice under all conditions. Light adaptation was associated with a robust increase in b-wave amplitude in Gnat1−/− mice but, in contrast to wild types, almost no change in implicit time. Gnat1−/− mice retained circadian rhythms in the cone ERG with b-wave amplitudes larger and latencies reduced during the subjective day. Conclusions: Rod phototransduction has a strong suppressive effect on the cone ERG. Light adaptation in cone pathways relies in part on reductions in this effect, although mechanisms intrinsic to cone pathways also play an important role. Similarly, while changes in coupling between rod and cone pathways over the course of the day may contribute to circadian regulation of the cone pathway they are not sufficient to explain circadian rhythms in the wild-type cone ERG

A 10-micron Search for Inner-Truncated Disks Among Pre-Main-Sequence Stars With Photometric Rotation Periods

We use mid-IR (primarily 10 $\mu$m) photometry as a diagnostic for the presence of disks with inner cavities among 32 pre-main sequence stars in Orion and Taurus-Auriga for which rotation periods are known and which do not show evidence for inner disks at near-IR wavelengths. Disks with inner cavities are predicted by magnetic disk-locking models that seek to explain the regulation of angular momentum in T Tauri stars. Only three stars in our sample show evidence for excess mid-IR emission. While these three stars may possess truncated disks consistent with magnetic disk-locking models, the remaining 29 stars in our sample do not. Apparently, stars lacking near-IR excesses in general do not possess truncated disks to which they are magnetically coupled. We discuss the implications of this result for the hypothesis of disk-regulated angular momentum. Evidently, young stars can exist as slow rotators without the aid of present disk-locking, and there exist very young stars already rotating near breakup velocity whose subsequent angular momentum evolution will not be regulated by disks. Moreover, we question whether disks, when present, truncate in the manner required by disk-locking scenarios. Finally, we discuss the need for rotational evolution models to take full account of the large dispersion of rotation rates present at 1 Myr, which may allow the models to explain the rotational evolution of low-mass pre-main sequence stars in a way that does not depend upon braking by disks.Comment: 20 pages, 4 figure

Toxicity of cancer therapy: what the cardiologist needs to know about angiogenesis inhibitors

Clinical outcomes for patients with a wide range of malignancies have improved substantially over the last two decades. Tyrosine kinase inhibitors (TKIs) are potent signalling cascade inhibitors and have been responsible for significant advances in cancer therapy. By inhibiting vascular endothelial growth factor receptor (VEGFR)-mediated tumour blood vessel growth, VEGFR-TKIs have become a mainstay of treatment for a number of solid malignancies. However, the incidence of VEGFR-TKI-associated cardiovascular toxicity is substantial and previously under-recognised. Almost all patients have an acute rise in blood pressure, and the majority develop hypertension. They are associated with the development of left ventricular systolic dysfunction (LVSD), heart failure and myocardial ischaemia and can have effects on myocardial repolarisation. Attention should be given to rigorous baseline assessment of patients prior to commencing VEGFR-TKIs, with careful consideration of baseline cardiovascular risk factors. Baseline blood pressure measurement, ECG and cardiac imaging should be performed routinely. Hypertension management currently follows national guidelines, but there may be a future role forendothelin-1 antagonism in the prevention or treatment of VEGFR-TKI-associated hypertension. VEGFR-TKI-associated LVSD appears to be independent of dose and is reversible. Patients who develop LVSD and heart failure should be managed with conventional heart failure therapies, but the role of prophylactic therapy is yet to be defined. Serial monitoring of left ventricular function and QT interval require better standardisation and coordinated care. Management of these complex patients requires collaborative, cardio-oncology care to allow the true therapeutic potential from cancer treatment while minimising competing cardiovascular effects