Estimating plasma volume in neonatal Holstein calves fed one or two feedings of a lacteal-based colostrum replacer using Evans blue dye and hematocrit values at various time points.

Twenty-eight Holstein calves were blocked by birth date and randomly assigned to one of two treatments to investigate the effect of colostrum replacer (CR) feeding regimen on plasma volume (PV). Treatments were: 1) one feeding of CR (C1; 3L of reconstituted CR 675 g of powder providing 184.5 g of IgG at birth) or 2) two feedings of CR (C2; 2L of reconstituted CR at birth and 1 L of reconstituted CR at six h). By 6 h of age, all calves had received 3L of CR providing 184.5 g of IgG. Plasma volume was estimated at six, 12, 18, and 24 h after birth using Evans blue dye (EBD). No treatment effects were noted at any time points (P \u3e 0.05). Mean PV for all calves regardless of treatment at six, 12, 18, and 24 h were 78.6, 89.2, 83.9, and 90.7 mL kg-1 of BW, respectively. Plasma volume was correlated with hematocrit (HCT), initial HCT, and treatment. Hematocrit was correlated with PV, initial HCT, and body weight. Hematocrit for six, 12, 18 and 24 h after birth can be predicted with an initial precolostral HCT determination

Decoherence of matter waves by thermal emission of radiation

Emergent quantum technologies have led to increasing interest in decoherence - the processes that limit the appearance of quantum effects and turn them into classical phenomena. One important cause of decoherence is the interaction of a quantum system with its environment, which 'entangles' the two and distributes the quantum coherence over so many degrees of freedom as to render it unobservable. Decoherence theory has been complemented by experiments using matter waves coupled to external photons or molecules, and by investigations using coherent photon states, trapped ions and electron interferometers. Large molecules are particularly suitable for the investigation of the quantum-classical transition because they can store much energy in numerous internal degrees of freedom; the internal energy can be converted into thermal radiation and thus induce decoherence. Here we report matter wave interferometer experiments in which C70 molecules lose their quantum behaviour by thermal emission of radiation. We find good quantitative agreement between our experimental observations and microscopic decoherence theory. Decoherence by emission of thermal radiation is a general mechanism that should be relevant to all macroscopic bodies.Comment: 5 pages, 4 figure

Chirped pulse Raman amplification in warm plasma: towards controlling saturation

Stimulated Raman backscattering in plasma is potentially an efficient method of amplifying laser pulses to reach exawatt powers because plasma is fully broken down and withstands extremely high electric fields. Plasma also has unique nonlinear optical properties that allow simultaneous compression of optical pulses to ultra-short durations. However, current measured efficiencies are limited to several percent. Here we investigate Raman amplification of short duration seed pulses with different chirp rates using a chirped pump pulse in a preformed plasma waveguide. We identify electron trapping and wavebreaking as the main saturation mechanisms, which lead to spectral broadening and gain saturation when the seed reaches several millijoules for durations of 10's - 100's fs for 250 ps, 800 nm chirped pump pulses. We show that this prevents access to the nonlinear regime and limits the efficiency, and interpret the experimental results using slowly-varying-amplitude, current-averaged particle-in-cell simulations. We also propose methods for achieving higher efficiencies.close0

Historical Accuracy in German Lyric Diction: A Study in Era-Appropriate Pronunciation of German in Classical Literature

In the performance of classical music, great pains are taken to retain the original practices produced by each era. A string quartet might tune their strings differently to produce an authentic Baroque sound, or a soprano might study to find a correct form of ornamentation for a Classical-era aria. As scholars\u27 knowledge of musicology deepens, musicians have greater opportunity to improve authenticity in performance and give modem audiences a glimpse into the past. It is the intent of this culminating paper to take this idea of historical accuracy and apply it to a field in which it has been neglected: German diction

Targeted knock-down of miR21 primary transcripts using snoMEN vectors induces apoptosis in human cancer cell lines

We have previously reported an antisense technology, 'snoMEN vectors', for targeted knock-down of protein coding mRNAs using human snoRNAs manipulated to contain short regions of sequence complementarity with the mRNA target. Here we characterise the use of snoMEN vectors to target the knock-down of micro RNA primary transcripts. We document the specific knock-down of miR21 in HeLa cells using plasmid vectors expressing miR21-targeted snoMEN RNAs and show this induces apoptosis. Knock-down is dependent on the presence of complementary sequences in the snoMEN vector and the induction of apoptosis can be suppressed by over-expression of miR21. Furthermore, we have also developed lentiviral vectors for delivery of snoMEN RNAs and show this increases the efficiency of vector transduction in many human cell lines that are difficult to transfect with plasmid vectors. Transduction of lentiviral vectors expressing snoMEN targeted to pri-miR21 induces apoptosis in human lung adenocarcinoma cells, which express high levels of miR21, but not in human primary cells. We show that snoMEN-mediated suppression of miRNA expression is prevented by siRNA knock-down of Ago2, but not by knock-down of Ago1 or Upf1. snoMEN RNAs colocalise with Ago2 in cell nuclei and nucleoli and can be co-immunoprecipitated from nuclear extracts by antibodies specific for Ago2

Antenatal breast expression in women with diabetes: outcomes from a retrospective cohort study

Background: Women with diabetes are sometimes advised to express breast milk antenatally to prepare for breastfeeding and to store colostrum for infant feeding in preventing or treating hypoglycaemia after the birth. The acceptability, risks and benefits of this practice have not been evaluated. This was aimed to investigate the pattern of antenatal breast expression uptake and its relationship with birth outcomes in women with diabetes. Methods: This was part of a two year retrospective cohort study of pregnant women with diabetes (type 1, 2 and gestational diabetes) who gave birth during 2001–2003 in Derby Hospitals NHS Foundation Trust (n = 94). The information on the practice of antenatal breastfeeding expression and birth outcomes was collected via self-administered questionnaires and by examining maternity records. Results: Thirty-seven percent of women (35/94) recalled that they were advised to express antenatally and 17% did (16/94). The mean gestational age at birth for women who hand-expressed was lower than that for those who did not (mean difference (MD) (95% confidence intervals (CI)): -1.2 (−2.4 to 0.04), p = 0.06). A higher proportion of babies from the antenatal expression group were admitted to special care baby units (SCBU) (MD (95% CI): 21% (−3.9 to 46.3). Conclusions: Less than half the women who stated that they were advised to express, did so. There seems to be an indication that antenatal breast milk expression and lower gestational age at birth are associated. The trend of a higher rate of SCBU admission for babies from the breast milk expression group compared to those who did not express antenatally is of concern. An appropriately-powered randomised controlled trial is needed to determine the safety of this practice and its acceptability to women and health professionals before it can be recommended for implementation in practice. Keywords: Diabetes, Antenatal, Breast milk expression, Retrospective, Gestational age, Cohort, Gestation</p

A Vast Thin Plane of Co-rotating Dwarf Galaxies Orbiting the Andromeda Galaxy

Dwarf satellite galaxies are thought to be the remnants of the population of primordial structures that coalesced to form giant galaxies like the Milky Way. An early analysis noted that dwarf galaxies may not be isotropically distributed around our Galaxy, as several are correlated with streams of HI emission, and possibly form co-planar groups. These suspicions are supported by recent analyses, and it has been claimed that the apparently planar distribution of satellites is not predicted within standard cosmology, and cannot simply represent a memory of past coherent accretion. However, other studies dispute this conclusion. Here we report the existence (99.998% significance) of a planar sub-group of satellites in the Andromeda galaxy, comprising approximately 50% of the population. The structure is vast: at least 400 kpc in diameter, but also extremely thin, with a perpendicular scatter <14.1 kpc (99% confidence). Radial velocity measurements reveal that the satellites in this structure have the same sense of rotation about their host. This finding shows conclusively that substantial numbers of dwarf satellite galaxies share the same dynamical orbital properties and direction of angular momentum, a new insight for our understanding of the origin of these most dark matter dominated of galaxies. Intriguingly, the plane we identify is approximately aligned with the pole of the Milky Way's disk and is co-planar with the Milky Way to Andromeda position vector. The existence of such extensive coherent kinematic structures within the halos of massive galaxies is a fact that must be explained within the framework of galaxy formation and cosmology.Comment: Published in the 3rd Jan 2013 issue of Nature. 19 pages, 4 figures, 1 three-dimensional interactive figure. To view and manipulate the 3-D figure, an Adobe Reader browser plug-in is required; alternatively save to disk and view with Adobe Reade

Coherent spinor dynamics in a spin-1 Bose condensate

Collisions in a thermal gas are perceived as random or incoherent as a consequence of the large numbers of initial and final quantum states accessible to the system. In a quantum gas, e.g. a Bose-Einstein condensate or a degenerate Fermi gas, the phase space accessible to low energy collisions is so restricted that collisions be-come coherent and reversible. Here, we report the observation of coherent spin-changing collisions in a gas of spin-1 bosons. Starting with condensates occupying two spin states, a condensate in the third spin state is coherently and reversibly created by atomic collisions. The observed dynamics are analogous to Josephson oscillations in weakly connected superconductors and represent a type of matter-wave four-wave mixing. The spin-dependent scattering length is determined from these oscillations to be -1.45(18) Bohr. Finally, we demonstrate coherent control of the evolution of the system by applying differential phase shifts to the spin states using magnetic fields.Comment: 19 pages, 3 figure

Sustainable deltas in the Anthropocene

What are the possible trajectories of delta development over the coming decades? Trajectories will be determined by the interactions of biophysical trends such as changing sediment supplies, subsidence due to compaction of sediment and climate change, along with key socio-economic trends of migration and urbanisation, agricultural intensification, demographic transition, economic growth and structural change of the economy. Knowledge and understanding of plausible trajectories can inform management choices for deltas in the Anthropocene, including new policy perspectives and innovative adaptation. The emergence of visionary delta management plans in some large deltas, such as the Bangladesh Delta Plan 2100, is an important and necessary component. This chapter synthesises the state of knowledge and highlights key elements of science that will inform decisions on future management of deltas.<br/

Can a falling tree make a noise in two forests at the same time?

It is a commonplace to claim that quantum mechanics supports the old idea that a tree falling in a forest makes no sound unless there is a listener present. In fact, this conclusion is far from obvious. Furthermore, if a tunnelling particle is observed in the barrier region, it collapses to a state in which it is no longer tunnelling. Does this imply that while tunnelling, the particle can not have any physical effects? I argue that this is not the case, and moreover, speculate that it may be possible for a particle to have effects on two spacelike separate apparatuses simultaneously. I discuss the measurable consequences of such a feat, and speculate about possible statistical tests which could distinguish this view of quantum mechanics from a ``corpuscular'' one. Brief remarks are made about an experiment underway at Toronto to investigate these issues.Comment: 9 pp, Latex, 3 figs, to appear in Proc. Obsc. Unr. Conf.; Fig 2 postscript repaired on 26.10.9