A longitudinal study of abnormalities on MRI and disability from multiple sclerosis

Background: In patients with isolated syndromes that are clinically suggestive of multiple sclerosis, such as optic neuritis or brain-stem or spinal cord syndromes, the presence of lesions as determined by T2-weighted magnetic resonance imaging (MRI) of the brain increases the likelihood that multiple sclerosis will develop. We sought to determine the relation between early lesion volume, changes in volume, and long-term disability. Methods: Seventy-one patients in a serial MRI study of patients with isolated syndromes were reassessed after a mean of 14.1 years. Disability was measured with the use of Kurtzke's Expanded Disability Status Scale (EDSS; possible range, 0 to 10, with a higher score indicating a greater degree of disability). Results: Clinically definite multiple sclerosis developed in 44 of the 50 patients (88 percent) with abnormal results on MRI at presentation and in 4 of 21 patients (19 percent) with normal results on MRI. The median EDSS score at follow-up for those with multiple sclerosis was 3.25 (range, 0 to 10); 31 percent had an EDSS score of 6 or more (including three patients whose deaths were due to multiple sclerosis). The EDSS score at 14 years correlated moderately with lesion volume on MRI at 5 years (r=0.60) and with the increase in lesion volume over the first 5 years (r=0.61). Conclusions: In patients who first present with isolated syndromes suggestive of multiple sclerosis, the increases in the volume of the lesions seen on magnetic resonance imaging of the brain in the first five years correlate with the degree of long-term disability from multiple sclerosis. This relation is only moderate, so the volume of the lesions alone may not be an adequate basis for decisions about the use of disease-modifying treatment

Development of a Responsive Small Spacecraft

The development of a small spacecraft bus is presented. The approach applied seeks to respond to the requirements of potential users as represented by a large data base of payload missions, while minimizing cost. The development results in a general purpose spacecraft design that is responsive to a wide range of mission requirements, and provides a clear definition of capabilities and interfaces to facilitate user mission design

Immunisation against gonadotrophin-releasing hormone (GnRH) reduces agonistic behaviours in male rangeland goats

Rangeland goat bucks were used to evaluate the efficacy of a commercially available anti-gonadotrophin-releasing hormone vaccine, Improvac (Zoetis Australia, West Ryde, NSW, Australia). The hypothesis tested was that immunisation would suppress testosterone secretion by the testis and agonistic behaviour between male goats. We also compared intervals of 2 and 4 weeks between primary and booster immunisations and monitored responses over a 2-month period. The 45 goats were split into three groups (n = 15): one group receiving the vaccination booster on Day 14, one group receiving the vaccination booster on Day 28, and the Control group receiving sterile saline injections. Body mass, body condition score and scrotal circumference were measured fortnightly, and blood was collected at 2-week intervals and analysed for testosterone concentration. Behavioural interaction tests of 2-min duration were also conducted fortnightly. There was a significant decrease in paired testicular circumference (P < 0.05) and testosterone concentration (P < 0.01) in both vaccination groups by the end of the experiment at Day 60, compared with the Control group. Agonistic interactions measured at Day 60 were significantly reduced in both vaccination groups (P < 0.05) compared with the Control group. These results support the efficacy of Improvac in reducing agonistic behaviours in rangeland goat bucks and suggest that the use of the vaccine may assist in reducing social stress and possible injury in groups of confined male goats

Using cascading Bloom filters to improve the memory usage for de Brujin graphs

De Brujin graphs are widely used in bioinformatics for processing next-generation sequencing data. Due to a very large size of NGS datasets, it is essential to represent de Bruijn graphs compactly, and several approaches to this problem have been proposed recently. In this work, we show how to reduce the memory required by the algorithm of [3] that represents de Brujin graphs using Bloom filters. Our method requires 30% to 40% less memory with respect to the method of [3], with insignificant impact to construction time. At the same time, our experiments showed a better query time compared to [3]. This is, to our knowledge, the best practical representation for de Bruijn graphs.Comment: 12 pages, submitte

Plant domestication, the brave old world of genetic modification

The genetic improvement of crop plants via the newer techniques of biotechnology to produce \u201cgenetically modified\u201d crops is a significant driver of progress in agriculture. However, progress has not been unimpeded: various controversies swirl around the benefits, uniqueness, supposed risks and other aspects of \u201cGMOs\u201d, or genetically modified organisms\u2014which, as we explain, is a meaningless \u201ccategory\u201d\u2014and the foods derived from them. In order to resolve the conundrums posed by those issues, it is important to understand the pedigree of genetic modification, which had its inceptionin the domestication of plants. In this chapter, we briefly introduce the crucial determinants of the \u201cdomestication syndrome\u201d for cereals and legumes\u2014that is, loss of seed shattering and reduced seed dormancy\u2014and how it evolved through the ages into contemporary \u201cgenetic modification\u201d. We argue that the application of genetic engineering to crops within a few years brought a wave of improved domestication traits. Moreover, contrary to most of the early domestication traits, some of these novel traits are advantageous to the crop and not just to humans. The other chapters in this volume discuss current developments in technology, the promise of modern molecular genetic engineering, and the legal and regulatory landscape

Intrinsic decoherence and classical-quantum correspondence in two coupled delta-kicked rotors

We show that classical-quantum correspondence of center of mass motion in two coupled delta-kicked rotors can be obtained from intrinsic decoherence of the system itself which occurs due to the entanglement of the center of mass motion to the internal degree of freedom without coupling to external environment

Decoherence from a Chaotic Environment: An Upside Down "Oscillator" as a Model

Chaotic evolutions exhibit exponential sensitivity to initial conditions. This suggests that even very small perturbations resulting from weak coupling of a quantum chaotic environment to the position of a system whose state is a non-local superposition will lead to rapid decoherence. However, it is also known that quantum counterparts of classically chaotic systems lose exponential sensitivity to initial conditions, so this expectation of enhanced decoherence is by no means obvious. We analyze decoherence due to a "toy" quantum environment that is analytically solvable, yet displays the crucial phenomenon of exponential sensitivity to perturbations. We show that such an environment, with a single degree of freedom, can be far more effective at destroying quantum coherence than a heat bath with infinitely many degrees of freedom. This also means that the standard "quantum Brownian motion" model for a decohering environment may not be as universally applicable as it once was conjectured to be.Comment: RevTeX, 29 pages, 5 EPS figures. Substantially rewritten analysis, improved figures, additional references, and errors fixed. Final version (to appear in PRA

Remote identification of sheep with flystrike using behavioural observations

Flystrike is a major problem affecting sheep in Australia. Identification of &amp;lsquo;flystruck&amp;rsquo; individuals is crucial for treatment; but requires labour-intensive physical examination. As the industry moves toward more low-input systems; there is a need for remote methods to identify flystruck individuals. The aim of this study was to investigate the behaviour of sheep with breech flystrike within a paddock setting. Video footage of sixteen Merino sheep; eight later confirmed with flystrike and eight without; was collected as they moved freely within the paddock with conspecifics. Quantitative behavioural measurements and a qualitative behavioural assessment (QBA) were conducted and compared to their breech conditions (i.e., faecal/urine staining; flystrike severity). Both qualitative and quantitative assessments indicated behavioural differences between flystruck and non-flystruck animals. Flystruck sheep had a behavioural profile characterised by restless behaviour; abnormal postures and reduced grazing time (&lt;i&gt;p&lt;/i&gt; &amp;lt; 0.05). Furthermore; flystruck sheep were scored to have a more &amp;lsquo;exhausted/irritated&amp;rsquo; demeanour using QBA (&lt;i&gt;p&lt;/i&gt; &amp;lt; 0.05). The behavioural responses also corresponded to the flystrike severity scores and condition of the breech area. We conclude that remotely assessed behaviour of flystruck sheep diverges markedly from non-flystruck sheep; and thus could be a low-input method for identifying and treating affected animals

A Comparative Study of the Formation of Aromatics in Rich Methane Flames Doped by Unsaturated Compounds

For a better modeling of the importance of the different channels leading to the first aromatic ring, we have compared the structures of laminar rich premixed methane flames doped with several unsaturated hydrocarbons: allene and propyne, because they are precursors of propargyl radicals which are well known as having an important role in forming benzene, 1,3-butadiene to put in evidence a possible production of benzene due to reactions of C4 compounds, and, finally, cyclopentene which is a source of cyclopentadienylmethylene radicals which in turn are expected to easily isomerizes to give benzene. These flames have been stabilized on a burner at a pressure of 6.7 kPa (50 Torr) using argon as dilutant, for equivalence ratios (?) from 1.55 to 1.79. A unique mechanism, including the formation and decomposition of benzene and toluene, has been used to model the oxidation of allene, propyne, 1,3 butadiene and cyclopentene. The main reaction pathways of aromatics formation have been derived from reaction rate and sensitivity analyses and have been compared for the three types of additives. These combined analyses and comparisons can only been performed when a unique mechanism is available for all the studied additives