In this article, we introduce Wireless 2.0, the future generation of wireless communication networks, in which the radio environment becomes controllable and intelligent by leveraging the emerging technologies of reconfigurable metasurfaces (RMSs) and artificial intelligence (AI). In particular, we emphasize AI-based computational methods and commence with an overview of the concept of intelligent radio environments (IREs) based on RMSs. Then, we elaborate on data management aspects, the requirements of supervised learning by examples, and the paradigm of reinforcement learning to learn by acting. Finally, we highlight numerous open challenges and research directions.

Twenty years after Povinelli’s “Folk Physics for Apes”, this paper assesses how researchers have made claims about animal physical cognition, and the statistical inferences that have been used to support them. These data are relevant in light of the current replicability issues facing science. We surveyed 116 published experiments from 63 papers on physical cognition, which included data from 43 different species of animals. Across these experiments most sample sizes were small, with often fewer than 10 animals being tested. However, in contrast to related psychological disciplines, we found that only 62% of our sample of physical cognition research made positive claims. This suggests that animal physical cognition does not have a strong publication bias towards positive results. Furthermore, we found evidence that researchers are making many true statistical inferences at the individual level, i.e. whether individual animals pass certain tests of physical cognition or not. In contrast, the strength of evidence of statistical effects at the group level was weaker and consistent with many effect sizes being overestimated. Overall, our analysis provides a cautiously optimistic analysis of reliability and bias in animal physical cognition research, however it is nevertheless likely that a non-negligible proportion of results will be difficult to replicate.

Brain derived neurotrophic factor (BDNF) has been implicated in the pathophysiology of schizophrenia. As BDNF regulates axonal and dendritic growth, altered BDNF levels in schizophrenia patients might underlie changes in structural connectivity that have been identified by magnetic resonance imaging (MRI). We investigated a possible correlation between BDNF serum levels, fiber tract architecture, and regional grey matter volumes in 19 schizophrenia patients and a gender- and age-matched control group. Two patients had to be excluded due to abnormalities in their MRI scans. Serum samples were obtained to determine BDNF levels, and T1- as well as diffusion-weighted sequences were acquired. We, then, investigated correlations between BDNF serum levels with neuroimaging parameters, using Voxel-based Morphometry (VBM) and Tract-based Spatial Statistics (TBSS). We found a significant negative correlation between BDNF serum levels and FA values in the right inferior fronto-occipital fasciculus and the right superior longitudinal fasciculus. These regions also showed a decrease in AD values in schizophrenia patients. Grey matter volumes were reduced in patients but there was no correlation between regional grey matter volumes and BDNF. The right superior longitudinal fasciculus has been repeatedly identified to exhibit microstructural changes in schizophrenia patients. Our findings of a negative correlation between BDNF and FA values in patients might indicate that BDNF is upregulated to compensate decreased structural connectivity as it induces neural plasticity and shows increased levels in damaged tissue. These findings of our pilot study are encouraging leads for future research in larger samples.

Over the past few years, the interest of material scientists for metal and metal oxide nanoparticles (NPs) is increasing dramatically because of their unique physicochemical characteristics such as catalytic activity and optical, electronic, antibacterial, and magnetic properties which depend on their size, shape, and chemical surroundings. Recently, several new routes of synthesis of lead monoxide (PbO) nanoparticles have been used, such as chemical synthesis, calcination, sol-gel pyrolysis, anodic oxidation, solvothermal method, thermal decomposition, chemical deposition, laser ablation, and green methods. Essentially, for the structural characterization of lead oxide nanoparticles, several spectroscopic, microscopic, and thermogravimetric methods of analysis are used. Lead oxide has been widely utilized in batteries, gas sensors, pigments, ceramics, and glass industry. Furthermore, lead oxide nanoparticles are graded as toxic and dangerous for the human health and environment. Therefore, there is an urgent need to develop new approaches and standardized test procedures to study the potential hazardous effect of nanoparticles on the human health and environment. The aim of this chapter is to provide an overview of the recent trends in synthesis of lead oxide nanoparticles, their characterization, possible applications, and toxicity.

In September 2019, Marina Abramović's exhibition, The Cleaner, billed as her “European retrospective,” opened in Belgrade. The funding for the exhibit was secured through a direct intervention that came from Serbian prime minister Ana Brnabić. The Cleaner quickly became the center of a vigorous political debate, which exposed hypocrisies of the regime of illiberal democracy currently in power in Serbia.

The role of robots in society keeps expanding and diversifying, bringing with it a host of issues surrounding the relationship between robots and humans. This introduction to human–robot interaction (HRI) by leading researchers in this developing field is the first to provide a broad overview of the multidisciplinary topics central to modern HRI research. Written for students and researchers from robotics, artificial intelligence, psychology, sociology, and design, it presents the basics of how robots work, how to design them, and how to evaluate their performance. Self-contained chapters discuss a wide range of topics, including speech and language, nonverbal communication, and processing emotions, plus an array of applications and the ethical issues surrounding them. This revised and expanded second edition includes a new chapter on how people perceive robots, coverage of recent developments in robotic hardware, software, and artificial intelligence, and exercises for readers to test their knowledge.

The main reason for the selection of single-carrier frequency division multiple access (SC-FDMA) modulation technique in mobile high data rate communications lays in its low value of peak-to-average power ratio (PAPR). If spatial modulation, a multiple-input multiple-output technique that achieves bitrate increase, is applied to the SC-FDMA system in its conventional form, the PAPR level is increased. Hence, based on previously mentioned, in this paper, we provide the general design criteria for low PAPR spatial modulation (LPSM) implemented in SC-FDMA systems with multiple transmit antennas. The straightforward generalization of LPSM is derived and it is shown that it requires the number of transmit antennas to be doubled in order to add another bit in the spatial component. Based on that, the alternative generalized technique with higher number of spatial bits is proposed. As these techniques present single-stream generalizations, the approach with multiple-streams is proposed as well. After PAPR and performance comparisons, it is concluded that single-stream techniques outperform multiple-stream techniques in the cases of low overall data rate, whereas multiple-stream approach is better in high overall data rate scenarios. All proposed techniques maintain low PAPR level on all transmit antennas.

The main reason for the selection of single-carrier frequency division multiple access (SC-FDMA) modulation technique in mobile high data rate communications lays in its low value of peak-to-average power ratio (PAPR). If spatial modulation, a multiple-input multiple-output technique that achieves bitrate increase, is applied to the SC-FDMA system in its conventional form, the PAPR level is increased. Hence, based on previously mentioned, in this paper, we provide the general design criteria for low PAPR spatial modulation (LPSM) implemented in SC-FDMA systems with multiple transmit antennas. The straightforward generalization of LPSM is derived and it is shown that it requires the number of transmit antennas to be doubled in order to add another bit in the spatial component. Based on that, the alternative generalized technique with higher number of spatial bits is proposed. As these techniques present single-stream generalizations, the approach with multiple-streams is proposed as well. After PAPR and performance comparisons, it is concluded that single-stream techniques outperform multiple-stream techniques in the cases of low overall data rate, whereas multiple-stream approach is better in high overall data rate scenarios. All proposed techniques maintain low PAPR level on all transmit antennas.