Risk factors for admission and the role of respiratory syncytial virus-specific cytotoxic T-lymphocyte responses in children with acute bronchiolitis

Background. Risk factors for admission of children with acute bronchiolitis have remained controversial. Technological advances in the measurements of cytotoxic T-lymphocyte (CTL) activity, enable respiratory syncytial virus (RSV)-specific CTL activity to be studied in infants with bronchiolitis for the first time. We evaluated risk factors for admission of children with acute bronchiolitis and determined the role of CTL responses in those infected with RSV.Method. Children between 3 and 24 months of age presenting with bronchiolitis to the paediatric outpatient department at King Edward VIII Hospital, Durban, over a 1-year period were enrolled. Management included clinical evaluation, nasopharyngeal aspiration, standard treatment and hospitalisation if indicated. Secretions were tested with monoclonal antibodies for RSV and pooled respiratory viruses; shell vial cultures were also established. Permission was requested from parents of RSV-infected subjects for blood draws for specific cytotoxic T-cell assays and CD4/CD8 cells on admission and repeat CTL on day 7.Results. Viruses were identified in 55 of the 114 subjects studied (48.2%). RSV was seen in 41 cases (74.5%). Twenty three infants (20.2%) required admission. Risk factors associated with inpatient admissions on univariate analysis included younger mean age (7.6 months v. 10.1 months), overcrowding (p < 0.01) and indoor exposure to products of combustion of cooking fuels (p = 0.05). Only the former two were significant on multivariate analysis. RSV-specific CTL responses were obtained in 21 children (51.2%). Responses were either very weak (N = 7) or negative (N = 14) on day 0 and did not alter significantly on day 7. The mean CD4/CD8 ratios in this group were 2.27:1. The highest frequency of CTL was directed against the proteins 'M4/5/6', with counts ranging from 100 to 400 spot forming cells (sfc)/million.Conclusion. Measures to address risk factors identified in this study may decrease the need for hospitalisation from bronchiolitis. The lack of RSV-specific CTL responses in peripheral blood of immunocompetent RSV-infected children suggest an alternative method of induction of immunity or compartmentalisation of immune cells

Linear Temperature Variation of the Penetration Depth in YBCO Thin Films

We have measured the penetration depth $\lambda(T)$ on $\rm YBa_{2}Cu_{3}O_{7}$ thin films from transmission at 120, 330 and 510~GHz, between 5 and 50~K. Our data yield simultaneously the absolute value and the temperature dependence of $\lambda(T)$. In high quality films $\lambda(T)$ exhibits the same linear temperature dependence as single crystals, showing its intrinsic nature, and $\lambda(0)=1750\,{\rm \AA}$. In a lower quality one, the more usual $T^2$ dependence is found, and $\lambda(0)=3600\,{\rm \AA}$. This suggests that the $T^2$ variation is of extrinsic origin. Our results put the $d$-wave like interpretation in a much better position.Comment: 12 pages, revtex, 4 uuencoded figure

Path Tracking Control for Autonomous Driving Applications

Autonomous or self-driving vehicles are becoming a consolidate reality that involves both industrial and academic elds also for its impact in social and governmental communities, well far from automotive engineering. The intent of the present paper is to design an automatic steering control for an autonomous vehicle equipped with steer-by-wire and drive-by-wire technologies. The steering action is calculated to let the vehicle follow a reference path which is stored in a Digital Map properly built to be available in real-time. A Proportional + Derivative (PD) control strategy is deigned based on the Parameter State Approach (PSA) and it is coupled with a Feedforward (FF) term for improving the path tracking control in cornering maneuvers. Some experimental results are shown to demonstrates the ecacy of the controller presented

Potentials of Green Coding -- Findings and Recommendations for Industry, Education and Science -- Extended Paper

Progressing digitalization and increasing demand and use of software cause rises in energy- and resource consumption from information and communication technologies (ICT). This raises the issue of sustainability in ICT, which increasingly includes the sustainability of the software products themselves and the art of creating sustainable software. To this end, we conducted an analysis to gather and present existing literature on three research questions relating to the production of ecologically sustainable software ("Green Coding") and to provide orientation for stakeholders approaching the subject. We compile the approaches to Green Coding and Green Software Engineering (GSE) that have been published since 2010. Furthermore, we considered ways to integrate the findings into existing industrial processes and higher education curricula to influence future development in an environmentally friendly way.Comment: This document is the extended version of the literature report published at the German Informatik Conference titled "Potentials of Green Coding - Findings and Recommendations for Industry, Education and Science". This document has since been updated and expanded to include relevant source

Negative longitudinal magnetoresistance from anomalous N=0 Landau level in topological materials

Negative longitudinal magnetoresistance (NLMR) is shown to occur in topological materials in the extreme quantum limit, when a magnetic field is applied parallel to the excitation current. We perform pulsed and DC field measurements on Pb1-xSnxSe epilayers where the topological state can be chemically tuned. The NLMR is observed in the topological state, but is suppressed and becomes positive when the system becomes trivial. In a topological material, the lowest N=0 conduction Landau level disperses down in energy as a function of increasing magnetic field, while the N=0 valence Landau level disperses upwards. This anomalous behavior is shown to be responsible for the observed NLMR. Our work provides an explanation of the outstanding question of NLMR in topological insulators and establishes this effect as a possible hallmark of bulk conduction in topological matter.Comment: Accepted in Physical Review Letter

Electron and hole states in quantum-dot quantum wells within a spherical 8-band model

In order to study heterostructures composed both of materials with strongly different parameters and of materials with narrow band gaps, we have developed an approach, which combines the spherical 8-band effective-mass Hamiltonian and the Burt's envelope function representation. Using this method, electron and hole states are calculated in CdS/HgS/CdS/H_2O and CdTe/HgTe/CdTe/H_2O quantum-dot quantum-well heterostructures. Radial components of the wave functions of the lowest S and P electron and hole states in typical quantum-dot quantum wells (QDQWs) are presented as a function of radius. The 6-band-hole components of the radial wave functions of an electron in the 8-band model have amplitudes comparable with the amplitude of the corresponding 2-band-electron component. This is a consequence of the coupling between the conduction and valence bands, which gives a strong nonparabolicity of the conduction band. At the same time, the 2-band-electron component of the radial wave functions of a hole in the 8-band model is small compared with the amplitudes of the corresponding 6-band-hole components. It is shown that in the CdS/HgS/CdS/H_2O QDQW holes in the lowest states are strongly localized in the well region (HgS). On the contrary, electrons in this QDQW and both electron and holes in the CdTe/HgTe/CdTe/H_2O QDQW are distributed through the entire dot. The importance of the developed theory for QDQWs is proven by the fact that in contrast to our rigorous 8-band model, there appear spurious states within the commonly used symmetrized 8-band model.Comment: 15 pages, 5 figures, E-mail addresses: [email protected], [email protected]

Development and evaluation of a reference measurement model for assessing the resource and energy efficiency of software products and components—Green Software Measurement Model (GSMM)

In the past decade, research on measuring and assessing the environmental impact of software has gained significant momentum in science and industry. However, due to the large number of research groups, measurement setups, procedure models, tools, and general novelty of the research area, a comprehensive research framework has yet to be created. The literature documents several approaches from researchers and practitioners who have developed individual methods and models, along with more general ideas like the integration of software sustainability in the context of the UN Sustainable Development Goals, or science communication approaches to make the resource cost of software transparent to society. However, a reference measurement model for the energy and resource consumption of software is still missing. In this article, we jointly develop the Green Software Measurement Model (GSMM), in which we bring together the core ideas of the measurement models, setups, and methods of over 10 research groups in four countries who have done pioneering work in assessing the environmental impact of software. We briefly describe the different methods and models used by these research groups, derive the components of the GSMM from them, and then we discuss and evaluate the resulting reference model. By categorizing the existing measurement models and procedures and by providing guidelines for assimilating and tailoring existing methods, we expect this work to aid new researchers and practitioners who want to conduct measurements for their individual use cases