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There are 46 patients in insulin resistance group (76.7%) developed antiplatelet drug resistance, which was significantly more frequent than patients without insulin resistance (35%, P less then 0.0001). Insulin resistance was an independent risk factor for antiplatelet drug resistance in patients with recent ischemic stroke/TIA after adjusted for confounding factors (Odds Ratio 5.281; 95%CI, 2.15 to 13.01, P less then 0.0001).Conclusions Insulin resistance was an independent predictor for development of antiplatelet drug resistance in patients with recent minor ischemic stroke or TIA. More attention should be paid to recognize these patients and antithrombotic effect should be monitored when antiplatelet drugs were applied to these patients.

Delayed cerebral thrombosis has been described as a potential cause of cerebrovascular complications in patients with bacterial meningitis. We report a case of delayed cerebral thrombosis in a 63-year-old woman admitted for pneumococcal meningitis. Initially, there was a good clinical evolution under treatment with steroids and antibiotics. On day 8 after admission, she was found with a decreased level of consciousness. Her neurological condition gradually worsened. Repeated brain imaging showed extensive ischemic lesions. Despite treatment with high-dose corticosteroids, the patient died.

A literature search was conducted. Data on patient characteristics, diagnosis, treatment and outcome were collected.

To date, 28 cases with delayed cerebral thrombosis following bacterial meningitis have been reported. Streptococcus pneumoniae was the pathogen in 89% of cases. Clinical deterioration occurred in all patients, with a duration varying from 5 to 40days between admission and deterioration. Most common sympal findings and brain imaging, after excluding endocarditis. The underlying etiology remains unknown. When delayed cerebral thrombosis is suspected, high-dose corticosteroids should be started empirically. The prognosis remains poor with high mortality rates.Atmospheric contamination of plant raw material with Polycyclic Aromatic Hydrocarbons (PAHs) helps explain their presence in edible vegetable oils. This study compared PAH contamination of Turkish olive fruits during their growing period on the tree and their respective oils from three different industrial sources (petroleum refinery, thermal power plant and heavy industry site). The method included liquid-liquid extraction solid-phase extraction for cleanup followed by HPLC with fluorescence detector. There were statistically significant differences between the three industrial sources in benzo[a]pyrene content, the sum of light, total PAHs and PAH4 (p˂0.05), but only slight differences in PAH profiles. The highest level of PAH compounds was measured in samples exposed to pollution from the petroleum refinery, nearly twice as high as samples exposed to the thermal power plant which showed the lowest contamination levels. None of the samples analysed exceeded the limits stipulated by current legislation. The transfer ratios of PAH compounds from olives to olive oil were 22.8-73.2%. This indicates that PAHs either diffuse directly from skin to oil within the fruit or transfer during oil extraction.Sleep disturbance in mild cognitive impairment (MCI) is associated with progression to Alzheimer’s disease (AD), more severe AD symptoms, and worse health outcomes. The aim of this review was to examine the relationship between sleep and MCI, and the effectiveness of sleep improvement interventions for older adults with MCI or AD. An integrative review was conducted using four databases, and findings were analyzed using an iterative process. Findings from 24 studies showed that alterations in sleep increased the risk of MCI and that the sleep quality of individuals with MCI or AD was poorer than healthy controls. Changes in brain anatomy were also observed in healthy older adults with sleep disturbances. Examined interventions were shown to be effective in improving sleep. Screening for sleep disturbances in individuals with MCI/AD is crucial to mitigate neurodegenerative or neurobehavioral risks in this population.The stochastic resonance (SR) in a bistable system driven by nonlinear frequency modulation (NLFM) signal and strong noise is studied. Combined with empirical mode decomposition (EMD) and piecewise idea, an adaptive piecewise re-scaled SR method based on the optimal intrinsic mode function (IMF), is proposed to enhance the weak NLFM signal. At first, considering the advantages of EMD for dealing with non-stationary signals, the segmented NLFM signal is processed by EMD. Meanwhile, the cross-correlation coefficient is used as the measure to select the optimal IMF that contains the NLFM signal feature. Then, the spectral amplification gain indicator is proposed to realize the adaptive SR of the optimal IMF of each sub-segment signal and reconstruct the enhanced NLFM signal. Finally, the effectiveness of the proposed method is highlighted with the analysis of the short-time Fourier transform spectrum of the simulation results. As an application example, the proposed method is verified adaptability in bearing fault diagnosis under the speed-varying condition that represents a typical and complicated NLFM signal in mechanical engineering. The research provides a new way for the enhancement of weak non-stationary signals. This article is part of the theme issue ‘Vibrational and stochastic resonance in driven nonlinear systems (part 1)’.Adding noise to a system can ‘improve’ its dynamic behaviour, for example, it can increase its response or signal-to-noise ratio. The corresponding phenomenon, called stochastic resonance, has found numerous applications in physics, neuroscience, biology, medicine and mechanics. Replacing stochastic excitations with high-frequency ones was shown to be a viable approach to analysing several linear and nonlinear dynamic systems. For these systems, the influence of the stochastic and high-frequency excitations appears to be qualitatively similar. The present paper concerns the discussion of the applicability of this ‘deterministic’ approach to stochastic systems. First, the conventional nonlinear bi-stable system is briefly revisited. Then dynamical systems with multiplicative noise are considered and the validity of replacing stochastic excitations with deterministic ones for such systems is discussed. Finally, we study oscillatory systems with nonlinear damping and analyse the effects of stochastic and deterministic excitations on such systems. This article is part of the theme issue ‘Vibrational and stochastic resonance in driven nonlinear systems (part 1)’.Vibrational resonance (VR) intentionally applies high-frequency periodic vibrations to a nonlinear system, in order to obtain enhanced efficiency for a number of information processing tasks. Note that VR is analogous to stochastic resonance where enhanced processing is sought via purposeful addition of a random noise instead of deterministic high-frequency vibrations. Comparatively, due to its ease of implementation, VR provides a valuable approach for nonlinear signal processing, through detailed modalities that are still under investigation. In this paper, VR is investigated in arrays of nonlinear processing devices, where a range of high-frequency sinusoidal vibrations of the same amplitude at different frequencies are injected and shown capable of enhancing the efficiency for estimating unknown signal parameters or for detecting weak signals in noise. In addition, it is observed that high-frequency vibrations with differing frequencies can be considered, at the sampling times, as independent random variables. This property allows us here to develop a probabilistic analysis-much like in stochastic resonance-and to obtain a theoretical basis for the VR effect and its optimization for signal processing. These results provide additional insight for controlling the capabilities of VR for nonlinear signal processing. This article is part of the theme issue ‘Vibrational and stochastic resonance in driven nonlinear systems (part 1)’.Nonlinear systems are abundant in nature. Their dynamics have been investigated very extensively, motivated partly by their multidisciplinary applicability, ranging from all branches of physical and mathematical sciences through engineering to the life sciences and medicine. When driven by external forces, nonlinear systems can exhibit a plethora of interesting and important properties-one of the most prominent being that of resonance. In the presence of a second, higher frequency, driving force, whether stochastic or deterministic/periodic, a resonance phenomenon arises that can generally be termed stochastic resonance or vibrational resonance. Operating a system in or out of resonance promises applications in several advanced technologies, such as the creation of novel materials at the nano, micro and macroscales including, but not limited to, materials having photonic band gaps, quantum control of atoms and molecules as well as miniature condensed matter systems. Motivated in part by these potential applications, this 2-part Theme Issue provides a concrete up-to-date overview of vibrational and stochastic resonances in driven nonlinear systems. It assembles state-of-the-art, original contributions on such induced resonances-addressing their analysis, occurrence and applications from either the theoretical, numerical or experimental perspectives, or through combinations of these. This article is part of the theme issue ‘Vibrational and stochastic resonance in driven nonlinear systems (part 1)’.The vibrational resonance (VR) phenomenon has received a great deal of research attention over the two decades since its introduction. The wide range of theoretical and experimental results obtained has, however, been confined to VR in systems with constant mass. We now extend the VR formalism to encompass systems with position-dependent mass (PDM). We consider a generalized classical counterpart of the quantum mechanical nonlinear oscillator with PDM. Selleck BTK inhibitor By developing a theoretical framework for determining the response amplitude of PDM systems, we examine and analyse their VR phenomenona, obtain conditions for the occurrence of resonances, show that the role played by PDM can be both inductive and contributory, and suggest that PDM effects could usefully be explored to maximize the efficiency of devices being operated in VR modes. Our analysis suggests new directions for the investigation of VR in a general class of PDM systems. This article is part of the theme issue ‘Vibrational and stochastic resonance in driven nonlinear systems (part 1)’.A two-state system driven by two inputs has been found to consistently produce a response mirroring a logic function of the two inputs, in an optimal window of moderate noise. This phenomenon is called logical stochastic resonance (LSR). We extend the conventional LSR paradigm to implement higher-level logic architecture or typical digital electronic structures via carefully crafted coupling schemes. Further, we examine the intriguing possibility of obtaining reliable logic outputs from a noise-free bistable system, subject only to periodic forcing, and show that this system also yields a phenomenon analogous to LSR, termed Logical Vibrational Resonance (LVR), in an appropriate window of frequency and amplitude of the periodic forcing. Lastly, this approach is extended to realize morphable logic gates through the Logical Coherence Resonance (LCR) in excitable systems under the influence of noise. The results are verified with suitable circuit experiments, demonstrating the robustness of the LSR, LVR and LCR phenomena.