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Passband balanced steady state free precession (b-SSFP) fMRI employs the flat portion of the SSFP off-resonance response to obtain microscopic susceptibility changes elicited by changes in blood oxygenation following enhancement in neuronal activity. This technique can reduce geometric distortion and signal dropout while maintaining rapid acquisition and high signal-to-noise ratio (SNR) compared with traditional fMRI techniques. In the study, we developed a novel multi-phase passband b-SSFP fMRI technique that can achieve a spatial resolution of a few mm3 and a high temporal sampling rate of 50ms per slice at 7Tesla. This technique was further applied for an event-related (ER) fMRI paradigm. As a comparison, gradient-echo echo-planar imaging (GE-EPI) with similar spatial resolution and temporal sampling rate was carried out for the same ER-fMRI experiment. Experiments with visual cortex stimulation were carried out at 7Tesla to demonstrate whether the multi-phase b-SSFP technique and GE-EPI are able to differentiate temporal delays in hemodynamic response function (HRF) separated by 100ms in stimulus onset. Consistent with ERP results, the upslope of the HRF of both techniques can differentiate 100ms delay in stimulus onset, with the former showing a lower level of intersubject variability. The present study demonstrated that the multi-phase passband b-SSFP fMRI technique can be applied for resolving neuronal events on the order of 100ms at ultrahigh magnetic fields.

Abstract Satellite Based Augmentation System (SBAS) provides the corrections and integrity information to users, but as its signal format is opened to the public and Global Navigation Satellite System (GNSS) spoofing technology becomes more realistic, more feasible and cheaper. It's foreseeable that there will be risks of spoofing threats against SBAS in the future. SBAS signal authentication technology provides a system-level solution to spoofing threats by adding special markers to SBAS signals so that receivers can verify whether the SBAS signals are from the on-orbit Geostationary Earth Orbit (GEO) satellites or whether the signal information has been forged and tampered with. First, this article introduces the existing anti-spoofing methods that can be applied to SBAS, especially the Elliptic Curve Digital Signature Algorithm (ECDSA) and Timed Efficient Stream Loss-Tolerant Authentication (TESLA) protocols. Then it discusses four possible solutions in a combination with the existing SBAS Interface Control Document (ICD). Two main Key Performance Indicators (KPIs), Time Between Authentication (TBA) and Authentication Latency (AL), obtained in the four main scenarios are compared. By analyzing the EGNOS Authentication Security Testbed (EAST) test simulation results of European Geostationary Navigation Overlay Service (EGNOS) in Europe, the impact of SBAS after joining the authentication service is obtained.

The Tesla valve (TV), a valvular conduit invented by Nicola Tesla over a century ago, has recently acquired significant attention and application in various fields because of the growing interest in microfluidics and nanofluidics. The unique architecture of TV characterized by an asymmetrical design and an arc-shaped channel has long been an intriguing yet underrated design for building a passive component in a microfluidic system. While previously regarded as a technology without significant use, TV structures have been implemented in thermal manipulation fluidics, micromixers and micropumps, benefitting the advancement of urgently demanding technology in various areas, such as in biomedical diagnostics through wearable electronics and medical instruments, lab on a chip, chemosensors and in application toward sustainable technology manifested in fuel cell devices. This article presents the first comprehensive review of TV structures in the literature, which has seen significant growth in the last two years. The review discusses typical TV structures, including single-stage TV (STV), multistage TV (MSTV), and TV derivatives (TVD), along with their characteristics and potential applications. The designs of these structures vary based on their intended applications, but all are constructed based on the fundamental principle of the TV structure. Finally, future trends and potential applications of TV structures are summarized and discussed. This topical review provides a valuable reference for students, early-career scientists, and practitioners in fluidic devices, particularly those interested in using TV structures as passive components.

The article presents the discussion on computer-science papers emerging in proving valuable, interesting and informative for potential applications of AI in architecture. Topics include inquiry into the problem of designing architecture showing creativity, intuition, and sensibility; and opening up the possibility of style transfer such as transferring the stripes of a zebra onto a horse or reading an image through a neural network .

External search for knowledge and foresight have become strategically important activities for firms in an increasingly uncertain and complex business environment. Novel methods to monitor development are therefore essential for both firms and scholars. This article illustrates how firms can apply one such novel method called Social Media Analytics, a multiplatform approach incorporating multiple external sources drawn from Web 2.0, that enable external search for knowledge but simultaneously avoid information overload. To illustrate the potential of the method, this article draws upon a dataset spanning 36 months from August 2016 to August 2019 and 100 283 publicly posted user-generated contents concerning Tesla to analyze their autopilot and the controversies surrounding autonomous driving. The results show that indications of the regulatory scrutiny Tesla's driverless technology faced in 2019 could be seen in the data across several platforms at an early point and that these signals became stronger over time, especially on blogs and Facebook which exhibited strong indications of future regulatory scrutiny in contrast to Twitter and Instagram. Our results underscore the potential of the Social Media Analytics for external search for knowledge and open foresight that enable firms to tune in to weak signals and scan the periphery. [ABSTRACT FROM AUTHOR]

ObjectivesOur aim was to evaluate differences in metabolite levels between unmedicated patients with major depressive disorder (MDD) and healthy controls, to assess changes in metabolites in patients after they completed an 8-week course of mindfulness-based cognitive therapy (MBCT), and to exam the correlation between metabolites and depression severity.Materials and methodsSixteen patients with MDD and ten age- and gender-matched healthy controls were studied using 3D short echo-time (20 ms) magnetic resonance spectroscopic imaging (MRSI) at 7 Tesla. Relative metabolite ratios were estimated in five regions of interest corresponding to insula, anterior cingulate cortex (ACC), caudate, putamen, and thalamus.ResultsIn all cases, MBCT reduced severity of depression. The ratio of total choline-containing compounds/total creatine (tCr) in the right caudate was significantly increased compared to that in healthy controls, while ratios of N-acetyl aspartate (NAA)/tCr in the left ACC, myo-inositol/tCr in the right insula, and glutathione/tCr in the left putamen were significantly decreased. At baseline, the severity of depression was negatively correlated with my-inositol/tCr in the left insula and putamen. The improvement in depression severity was significantly associated with changes in NAA/tCr in the left ACC.ConclusionsThis study has successfully evaluated regional differences in metabolites for patients with MDD who received MBCT treatment and in controls using 7 Tesla MRSI.

The images of the Serbian-American scientist Nikola Tesla (1856–1943) often emerge in the analytic fields in Serbia, especially when they become paralyzed with feelings of hopelessness, despair and injustice. Tesla as a figure from the social unconscious becomes a sort of a 'helper' in the process of transformation of the field towards more hope and faith. This is not only due to Tesla images being used as metaphors, but also catalysing interactions in and between the fields, helping the transition from states of paralysis with annihilation anxieties towards livelier ones. Pichon Riviere's concepts of the spiral dialectics in transformation of the malignant repetitive circles into more benign is used for revealing changes of the most difficult – the bizarre 'black holes' in the fields. Vignettes from clinical group analysis and psychosocial work of the Reflective Citizens are presented as illustrations. Putting 'social creativity' and the 'paradigm of complexity' to work in dealing with social trauma in the Balkans is described -different fields inter-link to give meaning across different paradigms. [ABSTRACT FROM AUTHOR]

The term 'stock market' refers to a collection of global exchanges where the buying, selling, and issuance of shares for publicly held companies takes place. Market volatility is a measure of the variance of returns of shares listed on the stock market over a given period. High volatility is associated with high risk and unpredictability, and high volatility can be the product of economic factors, economic news, interest rate changes, and fiscal policy. One type of economic news comes from public figures that have the power to change market sentiment with their influence, as was seen with the Twitter account of United States President Donald Trump. Many of Trump's tweets were simply humorous or banal, corresponding to little impact on the behavior of financial markets. Trump's tweets were a common point of contention in political discourse and raised the question of whether a sitting president should have unrestricted access to social media, especially if their social media posts could influence market trends. With the weight that a president's word can carry, unregulated Twitter posts could have potential consequences on market volatility through influencing sentiment towards a company mentioned in the tweet (the 'targeted company'). This study aims to determine whether Trump's tweets had any lasting impact on the volatility of a targeted company's stock price. To determine this, a difference-in-difference (DD) model is implemented to compare the volatility of stock price between a targeted company and other non-targeted companies within the same sector. Additionally, a Fisher's Test for Independence is used to determine whether an increase in volatility of a targeted company's stock price and a Trump tweet were independent events. The results of the DD model did not find any evidence to disprove the relationship between Trump's tweets and the volatility of the targeted company's stock price. Furthermore, the results of the Fisher's Test indicate that Trump's tweets and the volatility of a targeted company's stock price are not independent events. This study concludes that Trump's tweets may have had an effect on a targeted company's stock price, but these effects were transient and caused no long-term change in stock prices. [ABSTRACT FROM AUTHOR]

For centuries, outside business organizations have sought to enter into business relationships with indigenous populations, often benefitting both parties. However, the power imbalance that foreign settlers had over indigenous peoples often led to exploitative relationships whereby the indigenous people were marginalized and at times treated inhumanely. While the nature of trade and relationships has changed over time, the special status that native tribes enjoy in U.S.A. continues to attract attention from business enterprises. In the past few years, various organizations have found it advantageous to their business interests to engage in transactions with Native American tribes. Three specific examples are described: Allergan transferred patent rights to a tribe to circumvent a U.S. patent review panel; Tesla opened a store and service center on native land in New Mexico to get around the state's dealership laws; and Lume Cannabis Co. opened retail stores on native lands in Michigan near communities that had decided to not license recreational cannabis stores. All three examples raise questions over the ethics of buying access to native sovereignty. Students are asked to apply ethical theories to try and identify what distinguishes ethical and unethical transactions. [ABSTRACT FROM AUTHOR]

The purpose of this article is to disclose the content of vertical integration strategies using Tesla as an example. In the theoretical part, the typology of integrated growth strategies is considered, and the feasibility of their application is substantiated. The practical part presents the experience of using such strategies with the Tesla electric vehicle manufacturer in the turbulent environment of the company.

For the past years, cryptocurrencies have been a hot and controversial topic that has captured the attention of the whole tech world. Even if right now the portfolio of digital assets is considerable in size, the first cryptocurrency, Bitcoin, exploited its pioneer advantage and managed to remain at the center of attention both for the media and investors. During 2020, one of the most chaotic years, Bitcoin boomed in November 2020 almost doubling since the end of 2019. This boom is the result of a combination of factors, such as the fear of missing out translated into a chain reaction of public and private companies to consider Bitcoin a safe reserve asset, a hedging method against inflation, which represents a substitute for traditional hedging instruments, the infrastructure developed around it over the years, and lastly the hype created by influential figures through news and social media platforms. There have been many public figures that exhibited interest in cryptocurrencies through platforms such as Twitter, for instance Elon Musk, Bill Gates, Kanye West, Hugh Laurie, Mike Tyson and Gwyneth Paltrow are just some in a long list of celebrities that backed Bitcoin. This paper aims to analyze the impact that twitter posts have upon the evolution of Bitcoin, coupled with Tesla's investment and recent statement of introducing Bitcoin as a method of payment in the near future. Our research tries to determine if the news and social media posts, such as tweets have an influence upon Bitcoin's volatility and fluctuations. [ABSTRACT FROM AUTHOR]

BackgroundTo validate six-echo, chemical-shift based MRI with T2 * correction for the quantification of bone marrow fat content in the presence of trabecular bone.MethodsTen bone phantoms were made using trabecular bone cores extracted from the distal femur and proximal tibia of 20 human cadaveric knees. Bone marrow was removed from the cores and the marrow spaces were filled with water-fat gelatin to mimic bone marrow of known fat fractions. A chemical-shift based water-fat separation method with T2 * correction was used to generate fat fraction maps. The proton density fat fractions (PDFF) between marrow regions with and without bone were compared with the reference standard of known fat fraction using the squared Pearson correlation coefficient and unpaired t-test.ResultsStrong correlations were found between the known fat fraction and measured PDFF in marrow without trabecular bone (R(2) = 0.99; slope = 0.99, intercept = 0.94) as well as in marrow with trabecular bone (R(2) = 0.97; slope = 1.0, intercept = -3.58). Measured PDFF between regions with and without bone were not significantly different (P = 0.5). However, PDFF was systematically underestimated by -3.2% fat fraction in regions containing trabecular bone.ConclusionOur implementation of a six-echo chemical-shift based MRI pulse sequence with T2 * correction provided an accurate means of determining fat content in bone marrow in the presence of trabecular bone.