Correction to: 6G and the UN SDGs: Where is the Connection?

Wireless Personal Communications - With the evolution of smart grid system (SGS), many issues associated with traditional grid network, i.e., power system security, monitoring and control, energy...     

Secreted Extracellular Vesicle Molecular Cargo as a Novel Liquid Biopsy Diagnostics of Central Nervous System Diseases

Secreted extracellular vesicles (EVs) are heterogeneous cell-derived membranous granules which carry a large diversity of molecules and participate in intercellular communication by transferring these molecules to target cells by endocytosis. In the last decade, EVs’ role in several pathological conditions, from etiology to disease progression or therapy evasion, has been consolidated, including in central nervous system (CNS)-related disorders. For this review, we performed a systematic search of original works published, reporting the presence of molecular components expressed in the CNS via EVs, which have been purified from plasma, serum or cerebrospinal fluid. Our aim is to provide a list of molecular EV components that have been identified from both nonpathological conditions and the most common CNS-related disorders. We discuss the methods used to isolate and enrich EVs from specific CNS-cells and the relevance of its components in each disease context.     

Analysis of dynamic capabilities for spectrum sharing in the citizens broadband radio service

This paper seeks to identify and analyze the sources of value creation and capture by key stakeholders in the new Citizens Broadband Radio Service (CBRS) three tier spectrum sharing framework introduced by the US President’s Council of Advanced Science & Technology. More flexible and dynamic use of the 3.5 GHz spectrum aims to increase the efficiency of spectrum use in delivering fast growing and converging mobile broadband and media services while paving the way to innovations in technology and business models. In this paper, we focus on key stakeholders’ capability to deal with combined internal and external resources and capabilities in doing business, referred to as dynamic capability. Spectrum sharing, introducing a rapid change in the technology and business environments, requires dynamic capabilities from spectrum offering, spectrum utilization, and spectrum management perspectives. We focus on defining key CBRS functional domains and identifying their key antecedents, elements, and outcomes. The analysis highlights the key role of the regulator in creating a sharing framework with incentives for all the key stakeholders, with different operational and business requirements, and enabling scaling ecosystem. Increased system dynamics in spectrum sharing will introduce a need for big data analytics, near real time network management capabilities and low cost third tier general authorized access radios, leveraging dominant technology ecosystems. This study provides viewpoints for stakeholders about additional ingredients and actions, which may be relevant to promote spectrum sharing in the form of the CBRS. The concept of dynamic capabilities was found useful to analyze the sources of competitive advantage regarding CBRS spectrum sharing.     

Parallelized Bayesian inversion for three-dimensional dental X-ray imaging

Diagnostic and operational tasks based on dental radiology often require three-dimensional (3-D) information that is not available in a single X-ray projection image. Comprehensive 3-D information about tissues can be obtained by computerized tomography (CT) imaging. However, in dental imaging a conventional CT scan may not be available or practical because of high radiation dose, low-resolution or the cost of the CT scanner equipment. In this paper, we consider a novel type of 3-D imaging modality for dental radiology. We consider situations in which projection images of the teeth are taken from a few sparsely distributed projection directions using the dentist's regular (digital) X-ray equipment and the 3-D X-ray attenuation function is reconstructed. A complication in these experiments is that the reconstruction of the 3-D structure based on a few projection images becomes an ill-posed inverse problem. Bayesian inversion is a well suited framework for reconstruction from such incomplete data. In Bayesian inversion, the ill-posed reconstruction problem is formulated in a well-posed probabilistic form in which a priori information is used to compensate for the incomplete information of the projection data. In this paper we propose a Bayesian method for 3-D reconstruction in dental radiology. The method is partially based on Kolehmainen et al. 2003. The prior model for dental structures consist of a weighted /spl lscr//sup 1/ and total variation (TV)-prior together with the positivity prior. The inverse problem is stated as finding the maximum a posteriori (MAP) estimate. To make the 3-D reconstruction computationally feasible, a parallelized version of an optimization algorithm is implemented for a Beowulf cluster computer. The method is tested with projection data from dental specimens and patient data. Tomosynthetic reconstructions are given as reference for the proposed method.     

Empirical comparison of process and economic input-output life cycle assessment in service industries

The study fills a gap in existing literature by comparing process-based and E10-based life cycle assessment (LCA) methods empirically in service industries. Despite the numerous methodological differences, the methods were found mostly to produce the same environmentally significant processes for the case organization: the use of electricity in the premises, the construction of the premises, the business travel by cars, the heating of the premises, and the business flights. However, the process-based LCA could not be used to assess the environmental impacts of purchased services properly. The study also recognized most of the theoretical differences listed in the literature, and found the ones related to the cut-offs in purchased services, the price inhomogeneity, and the industry-atypical electricity production have the greatest influence on results.     

Water activity in dry foods containing live probiotic bacteria should be carefully considered: a case study with Lactobacillus rhamnosus GG in flaxseed

This study evaluated the effect of water activity on the long-term storage stability of the probiotic Lactobacillus rhamnosus GG (LGG) in a dry food matrix. Viability of LGG was further studied in a crushed flaxseed matrix - a new possible product matrix to deliver probiotics - as well as in reference matrices as maltodextrin. Three different water activities (a(w)=0.11, 0.22 and 0.43) were used, and preparations were stored at room temperature for up to 14months. The viability of LGG was less dependent on the matrix used, but strongly dependent on the water activity. Viability in flaxseed was lost rapidly with a(w) 0.43: with a(w) 0.22 the reduction was 2.4 log(10) units and with a(w) 0.11 the reduction of viability was only 0.29 log(10) units during the entire storage time. Taken together, regulating water activity to a low value may offer possibilities for extending the shelf life of dry probiotic products.     

Seasonal Regulation of Metabolism: The Effect of Wintertime Fasting and Autumnal Fattening on Key Central Regulators of Metabolism and the Metabolic Profile of the Raccoon Dog (Nyctereutes Procyonoides)

Investigations into the mechanisms regulating obesity are frantic and novel translational approaches are needed. The raccoon dog (Nyctereutes procyonoides) is a canid species representing a promising model to study metabolic regulation in a species undergoing cycles of seasonal obesity and fasting. To understand the molecular mechanisms of metabolic regulation in seasonal adaptation, we analyzed key central nervous system and peripheral signals regulating food intake and metabolism from raccoon dogs after autumnal fattening and winter fasting. Expressions of neuropeptide Y (NPY), orexin-2 receptor (OX2R), pro-opiomelanocortin (POMC) and leptin receptor (ObRb) were analyzed as examples of orexigenic and anorexigenic signals using qRT-PCR from raccoon dog hypothalamus samples. Plasma metabolic profiles were measured with ¹H NMR-spectroscopy and LC-MS. Circulating hormones and cytokines were determined with canine specific antibody assays. Surprisingly, NPY and POMC were not affected by the winter fasting nor autumn fattening and the metabolic profiles showed a remarkable equilibrium, indicating conserved homeostasis. However, OX2R and ObRb expression changes suggested seasonal regulation. Circulating cytokine levels were not increased, demonstrating that the autumn fattening did not induce subacute inflammation. Thus, the raccoon dog developed seasonal regulatory mechanisms to accommodate the autumnal fattening and prolonged fasting making the species unique in coping with the extreme environmental challenges.     

Common cause failure analysis of cyber–physical systems situated in constructed environments

While cyber–physical system sciences are developing methods for studying reliability that span domains such as mechanics, electronics and control, there remains a lack of methods for investigating the impact of the environment on the system. External conditions such as flooding, fire or toxic gas may damage equipment and failing to foresee such possibilities will result in invalid worst-case estimates of the safety and reliability of the system. Even if single component failures are anticipated, abnormal environmental conditions may result in common cause failures that cripple the system. This paper proposes a framework for modeling interactions between a cyber–physical system and its environment. The framework is limited to environments consisting of spaces with clear physical boundaries, such as power plants, buildings, mines and urban underground infrastructures. The purpose of the framework is to support simulation-based risk analysis of an initiating event such as an equipment failure or flooding. The functional failure identification and propagation (FFIP) framework is extended for this purpose, so that the simulation is able to detect component failures arising from abnormal environmental conditions and vice versa: Flooding could be caused by a failure in a pipe or valve component. As abnormal flow states propagate through the system and its environment, the goal of the simulation is to identify the system-wide cumulative effect of the initiating event and any related common cause failure scenario. FFIP determines this effect in terms of degradation or loss of the functionality of the system. The method is demonstrated with a nuclear reactor’s redundant coolant supply system.     

Singularity extraction technique for integral equation methods with higher order basis functions on plane triangles and tetrahedra

A numerical solution of integral equations typically requires calculation of integrals with singular kernels. The integration of singular terms can be considered either by purely numerical techniques, e.g. Duffy's method, polar co‐ordinate transformation, or by singularity extraction. In the latter method the extracted singular integral is calculated in closed form and the remaining integral is calculated numerically. This method has been well established for linear and constant shape functions. In this paper we extend the method for polynomial shape functions of arbitrary order. We present recursive formulas by which we can extract any number of terms from the singular kernel defined by the fundamental solution of the Helmholtz equation, or its gradient, and integrate the extracted terms times a polynomial shape function in closed form over plane triangles or tetrahedra. The presented formulas generalize the singularity extraction technique for surface and volume integral equation methods with high‐order basis functions. Numerical experiments show that the developed method leads to a more accurate and robust integration scheme, and in many cases also a faster method than, for example, Duffy's transformation. Copyright © 2003 John Wiley & Sons, Ltd.     

Millimeter-Wave over Fiber Systems Using Hybrid OCDM/WDM Transmission

In this paper, we propose and simulate 2 OCDM × 4 WDM transmission system for a millimeter-wave (60 GHz) over fiber system to be used in broadband wireless access networks (BWANs). The general system setup is devised and the necessary building blocks identified. Results gathered (for a 155 Mbit/s per user system) under worst case parameter specifications and settings suggest indicate that system performance is severely limited by optical multiuser interference (OMUI) penalties. Several methods to reduce the OMUI limitations are described. These methods should ensure that this transmission scheme possible wavelength-reuse option for future MMW BWANs.