CURRENT ACCOUNT DEFICIT SUSTAINABILITY IN TRANSITION COUNTRIES

The current account balance represents the most important measurement of acountry's economic performance and it is important to keep the current account deficit within sustainable levels. Over the last decade, the importance of asustainable current account deficit has been major concern of policy makers and investors. In this paper, we investigate the sustainability of the current account deficit in transition countries over the period from 1995:01 through 2011:03, using intertemporal solvency model. According to this approach, the existence of aco integrating relationship between exports and imports + (including imports, netinterest payments and net transfer payments) gives that countries do not violate their intertemporal budget constraint. To achieve our objective, the cointegration test which recently developed in the presence of two potentially unknown structural breaks, is carried out. These breaks are taken into account in our analysis by considering that the long run relationship between related series might change andthe shifts can occur in the cointegrating vector. The obtained results suggest that there is evidence of cointegration for selected transition countries, implying sustainability

Investignation of applicability of solid state phantom SP34 for orthovoltage X-Ray

It is now widely used two types of tissue-equivalent phantoms: Solid and water. Water is the "gold standard" in accordance with the recommendations of the IAEA as a medium for measurements of absorbed dose for both photon and electron beams for, as the water has the most similar to human tissue characteristics. However, from a practical standpoint, water phantom is not always convenient to use, because it requires much time for preparation work. The output in such a situation would be to use a solid-state phantom with coefficients that take into account the difference between the electronic and physical material density against distilled water

Activation Energy of Metastable Amorphous Ge2Sb2Te5 from Room Temperature to Melt

Resistivity of metastable amorphous Ge2Sb2Te5 (GST) measured at device level show an exponential decline with temperature matching with the steady-state thin-film resistivity measured at 858 K (melting temperature). This suggests that the free carrier activation mechanisms form a continuum in a large temperature scale (300 K - 858 K) and the metastable amorphous phase can be treated as a super-cooled liquid. The effective activation energy calculated using the resistivity versus temperature data follow a parabolic behavior, with a room temperature value of 333 meV, peaking to ~377 meV at ~465 K and reaching zero at ~930 K, using a reference activation energy of 111 meV (3kBT/2) at melt. Amorphous GST is expected to behave as a p-type semiconductor at Tmelt ~ 858 K and transitions from the semiconducting-liquid phase to the metallic-liquid phase at ~ 930 K at equilibrium. The simultaneous Seebeck (S) and resistivity versus temperature measurements of amorphous-fcc mixed-phase GST thin-films show linear S-T trends that meet S = 0 at 0 K, consistent with degenerate semiconductors, and the dS/dT and room temperature activation energy show a linear correlation. The single-crystal fcc is calculated to have dS/dT = 0.153 {\mu}V/K for an activation energy of zero and a Fermi level 0.16 eV below the valance band edge.Comment: 5 pages, 5 figure

Exploring the role of the “glycan-shield” of human immunodeficiency virus in susceptibility to, and escape from, broadly neutralising antibodies

Philosophiae Doctor - PhDThe HIV-1 envelope (Env) glycoprotein is the primary target of the humoral immune response and a critical vaccine candidate. However, Env is densely glycosylated and thereby substantially protected from neutralisation. Despite the importance of the HIV- 1 Env glycans, limited computational analyses have been employed to analyse these glycans. Here, the Env glycans of two HIV-1 wild-type subtype C isolates are examined, in detail, using computational approaches. These particular strains were used since in vitro data showed that the removal of a single glycan had a substantially different impact on the neutralisation sensitivity of the two strains. Molecular dynamics simulations, and the subsequent analyses, were carried out on the computationally determined, fully glycosylated, Env structures of these two wild-type strains and their N301A mutant counterparts. Detailed comparison of the molecular dynamics simulations demonstrated that unique glycan dynamics and conformations emerged and that, despite shared HXB2 reference sequence positions, the glycans adopted distinct conformations specific to each wild-type model. Furthermore, different changes in conformations were observed for each wild-type model compared to its N301A mutant counterpart and, interestingly, these N301A mutant model-specific glycan conformations were directly associated with the protein residues ultimately found to be exposed, which may explain the varied resistance to neutralising antibodies observed, in vitro, for the two N301A mutant strains

Discrete Element Modeling of Cone Penetration in JSC-1A Lunar Regolith Simulant

NASA plans to return back to the Moon for a long term presence and use of the Moon as a launch station for further space exploration to other planets. This scenario increases the importance of determining the geotechnical properties of the lunar surface. However, due to the limited availability of lunar regolith and its high scientific value, a simulant material which closely matches the composition and grain size distribution and other characteristics of the lunar regolith has become an indispensable need to benefit in hardware development as well as estimating lunar regolith properties. Therefore, JSC-1A lunar regolith simulant, which was produced by Orbitec Company under the guidance of NASA, was provided for researchers to investigate soil parameters. Previous studies about JSC-1A utilized from conventional laboratory experiments. This thesis aims to examine the behavior of JSC-1A and auxiliary Ottawa sand against cone penetration testing (CPT). CPT is a fast and reliable method to characterize soil properties. Experimental work is augmented with numerical simulation to take advantage of powerful capabilities of discrete element method (DEM). Experimental work is mainly composed of two sets of tests. Firstly, CPT is conducted on JSC-1A in the field using a CPT truck and soil classification and internal friction angle analyses were estimated based on the test results. However, the limited data and high boundary effects on the container made a strong case to provide reliable reference for DEM simulations. Therefore, miniature CPT experiments were conducted for JSC-1A and Ottawa sand with distinctive densities using two size cylindrical containers. Ottawa sand which is a uniform silica sand is also included in the analysis to obtain supplementary data. Finally, DEM in 3D was used to model the response of two soils to cone penetration. Microscale changes such as contact force, displacement, velocity and stress variation of individual soil particles were monitored throughout the simulation process. In conclusion, CPT results show that each soil exhibits a characteristic response to cone penetration under different conditions. Its response is affected by various parameters such as soil density, boundary conditions, homogeneity, grain size and shape. It was found that boundary condition influence the results significantly. DEM results have a good agreement with laboratory experiments except the fluctuations in simulation data. The penetration of the cone produces a considerable variation in velocity and displacement field. Contact forces and deformation pattern of the granular material are mainly governed by the relative position of particles to the penetrometer

Motivation and incentives of rural maternal and neonatal health care providers: a comparison of qualitative findings from Burkina Faso, Ghana and Tanzania.

In Burkina Faso, Ghana and Tanzania strong efforts are being made to improve the quality of maternal and neonatal health (MNH) care. However, progress is impeded by challenges, especially in the area of human resources. All three countries are striving not only to scale up the number of available health staff, but also to improve performance by raising skill levels and enhancing provider motivation. In-depth interviews were used to explore MNH provider views about motivation and incentives at primary care level in rural Burkina Faso, Ghana and Tanzania. Interviews were held with 25 MNH providers, 8 facility and district managers, and 2 policy-makers in each country. Across the three countries some differences were found in the reasons why people became health workers. Commitment to remaining a health worker was generally high. The readiness to remain at a rural facility was far less, although in all settings there were some providers that were willing to stay. In Burkina Faso it appeared to be particularly difficult to recruit female MNH providers to rural areas. There were indications that MNH providers in all the settings sometimes failed to treat their patients well. This was shown to be interlinked with differences in how the term 'motivation' was understood, and in the views held about remuneration and the status of rural health work. Job satisfaction was shown to be quite high, and was particularly linked to community appreciation. With some important exceptions, there was a strong level of agreement regarding the financial and non-financial incentives that were suggested by these providers, but there were clear country preferences as to whether incentives should be for individuals or teams. Understandings of the terms and concepts pertaining to motivation differed between the three countries. The findings from Burkina Faso underline the importance of gender-sensitive health workforce planning. The training that all levels of MNH providers receive in professional ethics, and the way this is reinforced in practice require closer attention. The differences in the findings across the three settings underscore the importance of in-depth country-level research to tailor the development of incentives schemes

Iteration-Dependent Scaled Min-Sum Decoding for Low-Complexity Key Reconciliation in CV-QKD

We introduce an iteration-dependent scaled min-sum decoding for low-rate LDPC codes in CV-QKD, achieving near-sum product algorithm performance with reduced complexity, and facilitating CV-QKD hardware implementation.Comment: Accepted and to be presented at the Optical Fiber Communication Conference (OFC) 202

Embolisation for pulmonary arteriovenous malformation (Review)

Background: Pulmonary arteriovenous malformations are abnormal direct connections between the pulmonary artery and pulmonary vein which result in a right-to-left shunt. They are associated with substantial morbidity and mortality mainly from the effects of paradoxical emboli. Potential complications include stroke, cerebral abscess, pulmonary haemorrhage and hypoxaemia. Embolisation is an endovascular intervention based on the occlusion of the feeding arteries the pulmonary arteriovenous malformations thus eliminating the abnormal right-to-left-shunting. Objectives: To determine the efficacy and safety of embolisation in patients with pulmonary arteriovenous malformations including a comparison with surgical resection and different embolisation devices. Search methods: We searched the Cystic Fibrosis and Genetic Disorders Group's Trials Register; date of last search: 31 March 2014. We also searched the following databases: the Australian New Zealand Clinical Trials Registry; ClinicalTrials.gov; International Standard Randomised Controlled Trial Number Register; International Clinical Trials Registry Platform Search Portal (last searched 1 July 2014). We checked cross-references and searched references from review articles. Selection criteria: Trials in which individuals with pulmonary arteriovenous malformations were randomly allocated to embolisation compared to no treatment, surgical resection or embolisation using a different embolisation device. Data collection and analysis: Studies identified for potential inclusion were independently assessed for eligibility by two authors, with excluded studies further checked by a third author. No trials were identified for inclusion in the review and hence no analysis was performed. Main results: There were no randomised controlled trials included in the review; one ongoing trial has been identified which may be eligible for inclusion in the future. Authors' conclusions: There is no evidence from randomised controlled trials for embolisation of pulmonary arteriovenous malformations. However, randomised controlled trials are not always feasible on ethical grounds. Accumulated data from observational studies suggest that embolisation reduces morbidity. A standardised approach to reporting with long-term follow-up through registry studies can help to strengthen the evidence for embolisation in the absence of randomised controlled trials