415 research outputs found
Improving the efficiency of thermal covert channels in multi-/many-core systems
No full textIn many-core chips seen in mobile computing, data center, AI, and elsewhere, thermal covert channels could be established to transmit data (e.g., passwords), supposedly to be kept secret and private. Effectiveness of a thermal covert channel, measured by its transmission rate and bit error rate (BER), is so much dependent on the thermal noise/interference imposed on the channel. In this paper, we present a few techniques to improve the capacity of thermal covert channel by overcoming the thermal interference. In particular, data in a thermal covert channel are encoded and represented following a new thermal signaling scheme where logic value, 0 or 1, modules the thermal signals duty cycle. Next, we show in this study that proper selection of transmission frequency can significantly minimize thermal interference. In addition, we propose a robust end-to-end communication protocol for reliable communications. Our experiments have confirmed that, compared to an existing thermal covert channel attack [1] [2], a thermal covert channel enhanced with all the improvements proposed in this study is seeing significant BER reduction (by as much as 75%), and transmission rate boost (by more than threefold). Building such a strong thermal covert channel is the key step towards developing robust defense and countermeasures against information leaking over thermal covert channel.</p
Parteitage, Parteiführer und Führungswechsel in der KP Chinas
Get PDFVor gut 13 Jahren, im Juni 1989, übernahm Jiang Ze- min die Führung der KP Chinas - er ist damit schon jetzt der Politiker mit der zweitlängsten Amtszeit in der 81-jährigen Parteigeschichte, nur Mao Zedong hat länger regiert. Dies ist besonders bemerkenswert, wenn man berücksichtigt, dass allein in den zehn Jahren vor Jiangs Ernennung drei Vorgänger (Hua Guofeng, Hu Yaobang und Zhao Ziyang) gestürzt worden waren; Jiang ist auch der erste Parteichef seit Mao, der mehr als einen Parteitag im Amt überlebt hat
La signification politique du procès de Pékin
No full textPeking's Trial, by Wojtek Zafanolli
The political system that judged Jiang Qing, Mao Zedong's widow, and her three co-conspirators was not politically detached. Western countries failed to understand the reasons for this show-case trial that dominated the public's attention for more than two months. According to the author of this article, this trial must be considered in the light of the demaoization process launched more than two and a half years ago, the latest episode being the eviction of Hua Guofeng from the chairmanship of the party.Le procès de Pékin, par Wojtek Zafanolli
La justice qui a jugé Jiang Qing, la veuve de Mao Zedong, et ses trois co-inculpés de la "bande des quatre" était loin d'être sereine. Mais les motifs de cette savante mise en scène, qui a retenu l'attention de l'opinion publique mondiale pendant plus de deux mois, ont été très peu compris en Occident. L'auteur de cet article montre que ce procès doit être envisagé comme une étape du processus de démaoïsation entamé depuis plus de deux ans et demi et dont la dernière péripétie a été l'éviction de Hua Guofeng de son poste de président du parti.Zafanolli Wojtek. La signification politique du procès de Pékin. In: Politique étrangère, n°1 - 1981 - 46ᵉannée. pp. 163-170
Retina stimulation with low-frequency ultrasound in vivo
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PURPOSE: More and more researches are exploring the neuromodulation effect of ultrasound (US) on the central nervous system (e.g. brain and retina) and the peripheral nervous system (such as skin). US stimulation has been regarded as a new noninvasive neurostimulation approach by many researchers. Our previous studies had shown that the temporal response patterns of RGCs could be modulated by US in vitro. In this article, we studied US stimulation to the retina in vivo. This study attempted to use low-frequency (2.25 MHz) focused US to stimulate the rat eyes and investigate the effect on the primary visual cortex.
METHODS: Experiments were conducted on adult male and female Sprague Dawley rats (250–300 g). A 2.25 MHz focused US transducer (D = 0.75 in., SF = 2.0 in., Olympus, Waltham, MA, USA) was used to stimulate the rat eyes in vivo. Rats were anaesthetized with urethane (5 ml/kg, 20% aqueous solution, intraperitoneally; Sigma-Aldrich, Munich, Germany). Next, the rat was laid prone on an automatic heating pad (69002, RWD Life Science Co.) at 37℃ and with its head gently immobilized using a stereotaxic frame (68028, RWD Life Science Co.). The skin on the head was swabbed with iodine and then a local anesthetic (lidocaine hydrochloride, Lidocaine 0.5%, 1mL) was injected subcutaneously along the incision line. The skull was exposed and trephined in an area (4x4 mm2) overlaying the monocular visual cortex: 6.0 mm posterior to bregma, and 3.0 mm lateral from the midline, the depth of multi-electrode arrays implantation were 300-500µm below the pia surface. US stimulation was modulated in the pulsed mode, which parameters included: pulse repetition frequency (PRF) = 1 kHz, tone burst duration (TBD) = 0.5 ms, sonication duration (SD) = 300 ms, and inter-stimulus interval (ISI) = 3 s. In each experiment, 40 trials (stimulus trains) were delivered, and there were 2-min intervals between each experiment. The neural activities from the primary visual cortex was amplified, filtered and digitized by Cerebus 64-Channel system (Animal Use).
RESULTS: As shown in Fig. 1a, the low-frequency focused US (2.25 MHz) transducer was used to stimulate the rat left eye and a 4x4 multi-electrode array was used to record neural activities from the right primary visual cortex. Some preliminary experimental results showed that the local field potentials and the single neuron spikes recorded from the primary visual cortex were both changed by US stimulation. Fig. 1b showed the responses of local field potentials that were recorded by 13 electrodes to US stimulation. The average latency of these responses was about 250 ms, which was consistent with the previous study. The peri-stimulus time histogram (PSTH) of a single spiking unit that was sorted by Offline Sorter showed that the neuron responded to US stimulation at the offset Fig. 1c.
CONCLUSIONS: Such influence on the neural activities in brain demonstrated that the low-frequency focused US was capable of stimulating retinas in vivo, which might become a novel therapy tool for ophthalmic diseases.
Figure 1. US influenced on the neural activities of visual cortex. (a) The experimental paradigm. US stimulation to the rat left eye and multi-electrode arrays recording from the right primary visual cortex. (b) The local field potentials responded to US stimulation. X-axis is time (ms) and Y-axis is recording channels. (c) The PSTH of a single spiking unit that was sorted by Offline Sorter. X-axis is time (ms) and Y-axis is firing rate (Hz) .</p
Retinal Ganglion Cell Responses to Low-frequency Focused Ultrasound Stimulation
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PURPOSE: Acoustic retinal prosthesis has been put forward using high-frequency US with non-invasive and high-resolution advantages. But its application is limited by the difficulties in fabrication, energy consumption and acoustic attenuation. In the present study, low-frequency focused ultrasound stimulation (LFUS) had been demonstrated to activate retinal ganglion cells (RGCs) in rat retinas. The neurophysiological properties of RGC responses to LFUS were also investigated.
METHODS: A 2.25 MHz focused ultrasound transducer (D=0.75 in., SF=2.0 in.) was used to stimulate the rat retina which was cultured in a multi-electrode array system (MEA2100, MCS , Fig. 1). The acoustic property was evaluated by hydrophone (UMS3, Precision acoustics). Ultrasound (US) stimulation was modulated at pulsed mode. Light stimulation was modulated in the same mode to give an uniform field flashes. The electrophysiological data collected from MEA was detected for neural spikes and sorted by Plexon Offline Sorter. Only channels recording single-cell activities were adopted for subsequent analysis. Peri-stimulus time histograms and raster plots were plotted for each RGC using Spike 2.
RESULTS: In total, 116 retinal ganglion cells (RGCs) from 7 retinas were sorted and classified into four types according to light responses. The firing activity of 114 RGCs were modulated by repeated US stimulation. This suggested that low-frequency focused ultrasound stimulation (LFUS) could activate RGCs. The US responses didn’t correspond to the standard light responses and varied greatly between cell types. Besides, dual-peak responses to US stimulation were observed which were not reported previously. The temporal response properties of RGCs, including latency, firing rate, and response type, could be modulated by changing acoustic intensity.
CONCLUSIONS: These findings might imply a temporal neuromodulation effect of LFUS and provided an important foundation for the development of acoustic retinal prosthesis.</p
Identification of Immune Gene Signature Associated with T Cells and Natural Killer Cells in Type 1 Diabetes [Corrigendum]
Get PDFWang N, Wang G, Feng X, Yang T. Diabetes Metab Syndr Obes. 2024;17:2983—2996.
The authors have advised the affiliation callouts in the author list on page 2983 are incorrect. The correct author callouts should read as follows:
Na Wang1, Guofeng Wang1,2, Xiuli Feng1, Teng Yang
Corrigendum to 'A phosphorus/silicon-based, hyperbranched polymer for high-performance, fire-safe, transparent epoxy resins' [Polymer Degradation and Stability, 203 (2022) 110065]
No full textThe authors regret that the affiliation of Prof. Zhitian Liu in current manuscript is incorrect. The affiliation of Prof. Zhitian Liu is not ‘Center for Future Materials, University of Southern Queensland, Toowoomba 4350, Australia’, and his affilication is ‘Hubei Engineering Technology Research Center of Optoelectronic and New Energy Materials, School of Materials Science & Engineering, Wuhan Institute of Technology, Wuhan 430205, PR China’. Hence, the author and affilication list should be as follows. Qiu Shia, Siqi Huob, Cheng Wanga, Guofeng Yea, Lingfeng Yua, Zhengping Fangb, Hao Wangc, Zhitian Liua a Hubei Engineering Technology Research Center of Optoelectronic and New Energy Materials, School of Materials Science & Engineering, Wuhan Institute of Technology, Wuhan 430205, PR China b Laboratory of Polymer Materials and Engineering, NingboTech University, Ningbo 315100, PR China c Center for Future Materials, University of Southern Queensland, Toowoomba 4350, Australia The authors would like to apologise for any inconvenience caused
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