Magnetophoresis of Flexible DNA-based Dumbbell Structures

Controlled movement and manipulation of magnetic micro and nanostructures using magnetic forces can give rise to important applications in biomedecine, diagnostics and immunology. We report controlled magnetophoresis and stretching, in aqueous solution, of a DNA-based dumbbell structure containing magnetic and diamagnetic microspheres. The velocity and stretching of the dumbbell were experimentally measured and correlated with a theoretical model based on the forces acting on individual magnetic beads or the entire dumbbell structures. The results show that precise and predictable manipulation of dumbbell structures is achievable and can potentially be applied to immunomagnetic cell separators.Comment: 4 pages, 3 figures, preprint, to be published in AP

Landau damping of dust acoustic solitary waves in nonthermal plasmas

Dust acoustic (DA) solitary and shock structures have been investigated under the influence of Landau damping in a dusty plasma containing two temperature nonthermal ions. Motivated by the observations of Geotail spacecraft that reported two-temperature ion population in the Earth's magnetosphere, we have investigated the effect of resonant wave-particle interactions on DA nonlinear structures. The KdV equation with an additional Landau damping term is derived and its analytical solution is presented. The solution has the form of a soliton whose amplitude decreases with time. Further, we have illustrated the influence of Landau damping and nonthermality of the ions on DA shock structures by a numerical solution of the Landau damping modified KdV equation. The study of the time evolution of shock waves suggests that an initial shock-like pulse forms an oscillatory shock at later times due to the balance of nonlinearity, dispersion and disspation due to Landau damping. The findings of the present investigation may be useful in understanding the properties of nonlinear structures in the presence of Landau damping in dusty plasmas containing two temperature ions obeying nonthermal distribution such as in the Earth's magnetotail

Neutrino-driven instability of ion acoustic waves in an ultra-relativistic degenerate plasma

The coupling between ion-acoustic waves (IAWs) and a neutrino beam undergoing flavor oscillations in a dense, relativistically degenerate plasma is analyzed. The neutrino-driven streaming instability of the IAWs is investigated with relevance to plasma conditions at the last stage of stellar evolution in a massive supernova progenitor. The influence of neutrino beam parameters such as the energy of the incident neutrino beam and eigen-frequency of the neutrino flavor oscillations on the instability growth rate is obtained numerically. It is observed that the neutrino flavor oscillations significantly affect the neutrino-driven instability of the IAWs. Our results also indicate that the time period for the onset of the streaming neutrino-driven instability is shorter than the typical time period of a core-collapse supernova explosion. The findings of this investigation may shed new light on the understanding of underlying physical mechanism responsible for the core-collapse supernova

Rectal swabs as a viable alternative to faecal sampling for the analysis of gut microbiota functionality and composition

Faecal or biopsy samples are frequently used to analyse the gut microbiota, but issues remain with the provision and collection of such samples. Rectal swabs are widely-utilised in clinical practice and previous data demonstrate their potential role in microbiota analyses; however, studies to date have been heterogenous, and there is a particular lack of data concerning the utility of swabs for the analysis of the microbiota’s functionality and metabolome. We compared paired stool and rectal swab samples from healthy individuals to investigate whether rectal swabs are a reliable proxy for faecal sampling. There were no significant differences in alpha and beta diversity measures between swab and faecal samples, and inter-subject variability was preserved. Additionally, no significant differences were demonstrated in abundance of major annotated phyla. Inferred gut functionality using Tax4Fun2 showed excellent correlation between the two sampling techniques (Pearson’s coefficient r = 0.9217, P  < 0.0001). Proton nuclear magnetic resonance ( 1 H NMR) spectroscopy enabled the detection of 20 metabolites with good correlation between rectal swab and faecal samples for butyrate, succinate and 5-aminovalerate relative abundances, though more variable degrees of association for other identified metabolites. These data support the utility of rectal swabs in both compositional and functional analyses of the gut microbiota

Oesophageal Perforation: A diagnostic and therapeutic challenge in a resource limited setting. A report of three cases

Oesophageal perforation is a condition associated with a high mortality. Its management is still controversial with operative treatment being favoured but a shift to conservative management is occurring. Very little exists in medical literature about its management in Sub-Saharan Africa, where the paucity of thoracic surgeons is compounded by limited diagnostic and therapeutic facilities. We report three cases of oesophageal perforation which were all treated conservatively with tube thoracostomy, nil by mouth with feeding gastrostomy, intravenous antibiotics and chest physiotherapy. Two patients achieved oesophageal healing but one died due to severe septicaemia. In a resource restricted setting, conservative management which includes enteral nutrition by feeding gastrostomy, tube thoracostomy to drain inter pleural contaminants, intravenous antibiotics and chest physiotherapy is a safe and effective treatment for oesophageal perforations

Integrated functional visualization of eukaryotic genomes

BACKGROUND: Increasing amounts of data from large scale whole genome analysis efforts demands convenient tools for manipulation, visualization and investigation. Whole genome plots offer an intuitive window to the analysis. We describe two applications that enable users to easily plot and explore whole genome data from their own or other researchers' experiments. RESULTS: STRIPE and GFFtool (General Feature Format Tool) are softwares designed to support integration, visualization and exploration of whole genome data from eukaryotic genomes. STRIPE, in addition to providing a highly customizable and interactive data plot, provides access to numerous well-selected databases with updated information on all genes of a genome. GFFtool provides a user-friendly solution to integrating experimental data with the genomic information available in public databases. They also obviate the need for users to maintain large annotation resources, as they link to well-known resources using standard gene and protein identifiers. CONCLUSION: The programs provide the user with broad genomic overviews of data distribution, fast access to data of interest, and the ability to navigate speedily from one resource to another, and gain a better understanding of result of whole genome analysis experiments

Metastatic gastric cancer presenting with shoulder-hand syndrome: a case report

<p>Abstract</p> <p>Introduction</p> <p>Shoulder-hand syndrome is a relatively rare clinical entity classified as a complex regional pain syndrome type 1 and consisting essentially of a painful 'frozen shoulder' with disability, swelling, vasomotor or dystrophic changes in the homolateral hand. The pathophysiology is not completely clear but a predominant 'sympathetic' factor affecting the neural and vascular supply to the affected parts seems to be involved. Shoulder-hand syndrome has been related to many surgical, orthopedic, neurological and medical conditions; it is more often seen after myocardial infarction, hemiplegia and painful conditions of neck and shoulder, such as trauma, tumors, cervical discogenic or intraforaminal diseases and shoulder calcific tendinopathy, but has also been associated with herpetic infections, brain and lung tumors, thoracoplasty and drugs including phenobarbitone and isoniazid. The diagnosis of shoulder-hand syndrome is primarily clinical, but imaging studies, particularly bone scintigraphy, may be useful to exclude other disorders.</p> <p>Case presentation</p> <p>We report the case of a 67-year-old woman who presented with shoulder-hand syndrome as the initial manifestation of gastric cancer which had metastasized to bone.</p> <p>Conclusion</p> <p>Wider investigations are advisable in patients with atypical shoulder-hand syndrome. To the best of the authors' knowledge this is the first case of shoulder-hand syndrome associated with metastatic gastric cancer.</p

Population policies and education: exploring the contradictions of neo-liberal globalisation

The world is increasingly characterised by profound income, health and social inequalities (Appadurai, 2000). In recent decades development initiatives aimed at reducing these inequalities have been situated in a context of increasing globalisation with a dominant neo-liberal economic orthodoxy. This paper argues that neo-liberal globalisation contains inherent contradictions regarding choice and uniformity. This is illustrated in this paper through an exploration of the impact of neo-liberal globalisation on population policies and programmes. The dominant neo-liberal economic ideology that has influenced development over the last few decades has often led to alternative global visions being overlooked. Many current population and development debates are characterised by polarised arguments with strongly opposing aims and views. This raises the challenge of finding alternatives situated in more middle ground that both identify and promote the socially positive elements of neo-liberalism and state intervention, but also to limit their worst excesses within the population field and more broadly. This paper concludes with a discussion outling the positive nature of middle ground and other possible alternatives