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This article presents a multichannel EEG/BIOZ acquisition application specific integrated circuit (ASIC) with 4 EEG channels and a BIOZ channel, a switch resistor low-pass filter (SR-LPF). Each EEG channel includes a frontend, and a 4-channel multiplexed analog-to-digital converter (ADC), while the BIOZ channel features a pseudo sine current generator and a pair of readout paths with multiplexed SR-LPF and ADC. The ASIC is designed for size and power minimization, utilizing a 3-step ADC with a novel signal-dependent low power strategy. The proposed ADC operates at a sampling rate of 1600 S/s with a resolution of 15.2 bits, occupying only 0.093 mm2. With the help of the proposed signal-dependent low-power strategy, the ADC's power dissipation drops from 32.2 μW to 26.4 μW, resulting in an 18% efficiency improvement without performance degradation. Moreover, the EEG channels deliver excellent noise performance with a NEF of 7.56 and 27.8 nV/√Hz at the expense of 0.16 mm2 per channel. In BIOZ measurement, a 5-bit programmable current source is used to generate pseudo sine injection current ranging from 0 to 22 μApp, and the detection sensitivity reaches 2.4 mΩ/√Hz. Finally, the presented multichannel EEG/BIOZ acquisition ASIC has a compact active area of 1.5 mm2 in an 180nm CMOS technology.

This article presents a wirelessly powered closed-loop neuromodulation system, containing both implantable and wearable parts. The implantable part is an implantable neuromodulator tag that contains a customized application specific integrated circuit (ASIC) for neurostimulation and recording, an off-the-shelf near-field communication (NFC) proximity integrated circuit card (PICC) chip, and one coupling coil for communication and power transferring. There is a wireless monitoring device, an NFC reader, electroencephalogram (EEG) electrodes, and near-infrared spectrum (NIRS) modules in wearable part. Intracranial neural recorder and wearable EEG/NIRS modules are able to provide multimodal biological information, such as local field potentials (LFPs), EEG, and cerebral tissue oxygen saturation (StO $_{{2}}{)}$ for algorithms to propose a more precise closed-loop stimulation strategy for better treatment effect. The ASIC chip is fabricated in a 0.18- $\mu \text{m}$ CMOS technology. The stimulator has a limited size of 0.027 mm2. Its stimulation current ranges from 0 to 0.6 mA with a bandwidth of 10 Hz–8 kHz, which is able to support precise neuromodulation. The recording channel features a bandwidth of 0.5–100 Hz with a noise floor of $0.93 \mu \text{V}_{\text {rms}}$ . The entire neuromodulator tag has a small footprint of $20\times 24\times1.4$ mm, and its weight is only 0.25 g.

ABSTRACTPurposesThe purpose of this meta-analysis is to systematically compare the safety, efficacy, and predictability of small incision lenticule extraction (SMILE) and laser in situ keratomileusis (LASIK).MethodsThis study covered the data searched from the PubMed, the EMBASE and the Cochrane Library. The Cochrane Handbook was also referred to as evaluating the quality of the included studies. In addition, this meta-analysis was performed using Revman 5.4 software.ResultsA total of 11 randomized controlled trails (RCTs) were included. The proportion of eyes with refraction within ±0.5D was higher in LASIK group compared with SMILE group (RR, 0.91; 95% CI, 0.83 to 0.99; p= .04). The spherical aberration (SA) was smaller in SMILE group compared with LASIK group (RR, −0.12; 95% CI, −0.23 to −0.01; p= .04). There were no significant differences between two groups with regard to final mean refractive spherical equivalent (SE) (MD, −0.04; 95% CI, −0.12 to 0.03; p = .22), proportion of eyes losing one or more lines of corrected distance visual acuity (CDVA) (RR, 1.14; 95% CI, 0.58 to 2.27; p = .70), proportion of eyes with uncorrected distance visual acuity (UCVA) of 20/20 or better (RR, 0.99; 95% CI, 0.94 to 1.05; p = .71), postoperative mean logMAR UCVA (MD, 0.01; 95% CI, −0.00 to 0.03; p = .13), postoperative refraction within ±1.0D (RR, 1.00; 95% CI, 0.98 to 1.02; p = .60), postoperative astigmatism within ±0.25, 0.5 and 1.0D (RR, 0.80, 0.99, 1.00; 95% CI, 0.35 to 1.83, 0.94 to 1.05, 0.98 to 1.02; p = .60, 0.86, 0.87), postoperative higher order aberrations (HOAs) (RR, 0.00; 95% CI, −0.16 to 0.16; p = .99).ConclusionFor predictability, LASIK was superior to SMILE. There were comparably safety and efficacy for the correction of myopia and myopic astigmatism in SMILE and LASIK. SA was smaller after SMILE than after LASIK.

Enhancers and super-enhancers exert indispensable roles in maintaining cell identity through spatiotemporally regulating gene transcription. Meanwhile, active enhancers and super-enhancers also produce transcripts termed enhancer RNAs (eRNAs) from their DNA elements. Although enhancers have been identified for more than 30 years, widespread transcription from enhancers are just discovered by genome-wide sequencing and considered as the key to understand longstanding questions in gene transcription. RNA-transcribed enhancers are marked by histone modifications such as H3K4m1/2 and H3K27Ac, and enriched with transcription regulatory factors such as LDTFs, P300, CBP, BRD4 and MED1. Those regulatory factors might constitute a Mega-Trans-like complex to potently activate enhancers. Compared to mRNAs, eRNAs are quite unstable and play roles at local. Functionally, it has been shown that eRNAs promote formation of enhancer-promoter loops. Several studies also demonstrated that eRNAs help the binding of RNA polymerase II (RNAPII) or transition of paused RNAPII by de-association of the negative elongation factor (NELF) complex. Nevertheless, these proposed mechanisms are not universally accepted and still under controversy. Here, we comprehensively summarize the reported findings and make perspectives for future exploration. We also believe that super-enhancer derived RNAs (seRNAs) might be informative to understand the nature of super-enhancers.

Dynamic causal modeling (DCM) is a recently developed approach for effective connectivity measurement in the brain. It has attracted considerable attention in recent years and quite widespread used to investigate brain connectivity in response to different tasks as well as auditory, visual, and somatosensory stimulation. This method uses complex algorithms, and currently the only implementation available is the Statistical Parametric Mapping (SPM8) toolbox with functionality for use on EEG and fMRI. The objective of the current work is to test the robustness of the toolbox when applied to EEG, by comparing results obtained from various versions of the software and operating systems when using identical datasets. Contrary to expectations, it was found that estimated connectivities were not consistent between different operating systems, the version of SPM8, or the version of MATLAB being used. The exact cause of this problem is not clear, but may relate to the high number of parameters in the model. Caution is thus recommended when interpreting the results of DCM estimated with the SPM8 software.

We describe here the development of multifunctional nanocarriers, based on amine-functionalized biodegradable polyacrylamide nanoparticles (NPs), for cancer theranostics, including active tumor targeting, fluorescence imaging, and photodynamic therapy. The structural design involves adding primary amino groups and biodegradable cross-linkers during the NP polymerization, while incorporating photodynamic and fluorescent imaging agents into the NP matrix, and conjugating PEG and tumor-targeting ligands onto the surface of the NPs. The as-synthesized NPs are spherical, with an average diameter of 44 nm. An accelerated biodegradation study, using sodium hydroxide or porcine liver esterase, indicated a hydrogel polymer matrix chain collapse within several days. By using gel permeation chromatography, small molecules were detected, after the degradation. In vitrotargeting studies on human breast cancer cells indicate that the targeted NPs can be transported efficiently into tumor cells. Incubating the multifunctional nanocarriers into cancer cells enabled strong fluorescence imaging. Irradiation of the photosensitizing drug, incorporated within the NPs, with light of a suitable wavelength, causes significant but selective damage to the impregnated tumor cells, but only inside the illuminated areas. Overall, the potential of polymeric-based NPs as biodegradable, multifunctional nanocarriers, for cancer theranostics, is demonstrated here.

Deep brain stimulation applied to the periaqueductal grey matter (PAG) of the midbrain in humans has been shown to increase or decrease arterial blood pressure during rest and to resist the postural fall on standing. The mechanism by which this effect is elicited is unknown. We hypothesize that PAG stimulation modulates performance of the autonomic nervous system.

Fuel cells having proton conducting membranes comprising doped barium cerate ceramic BaCe0.85Y0.15O3-(BCY15) as electrolyte and platinum as both anode and cathode electrodes performed well for conversion of ethane to ethylene at 650 and 700 °C. No deterioration in performance occurred during 20 days of operation at 700 °C. The electrolyte was stable, and the membrane remained a single perovskite phase after long-term testing. Current density at maximum power density increased with temperature from 650 to 700 °C at ethane flow rates of 100−200 mL/min. A better seal and consequently a better performance were obtained when the sealant was under compression, achieved by operating the cell in vertical attitude. Power density of 120 mW/cm2was attained at current densities in the range 300−650 mA/cm2at 700 °C and ethane flow rate 100 mL/min. There was good agreement between current and change in gaseous composition across the anode. The protonic current arose in two ways:  by conversion of hydrogen arising from dehydrogenation of ethane, and by electrochemical conversion of ethane. At 650 °C the former is the major reaction path, while at 700 °C the latter is the major path.

Objectives. To determine whether deep brain stimulation is an effective treatment for neuropathic pain of varied etiology.

The periaqueductal grey matter is known to play a role in cardiovascular control in animals. Cardiovascular responses to electrical stimulation of the periventricularperiaqueductal grey matter were measured in 15 awake human study participants following implantation of deep brain stimulating electrodes for treatment of chronic pain. We found that stimulation of the ventral periventricularperiaqueductal grey matter caused a mean reduction in systolic blood pressure of 14.2±3.6 mmHg in seven patients and stimulation of the dorsal periventricularperiaqueductal grey matter caused a mean increase of 16.7±5.9 mmHg in six patients. A comparison between ventral and dorsal electrodes demonstrated significant differences (P<0.05). These changes were accompanied by analogous changes in diastolic blood pressure, pulse pressure, maximum dPdtbut not in the time interval between each R wave on the electrocardiogram.

Phantom limb pain (PLP) is a type of neuropathic pain syndrome that has evoked much interest in scientific and clinical fields. The condition is often intractable and severely debilitating. Though there are anecdotal reports in the literature of successful management of individual cases with brain and spinal cord stimulation, it has not been possible to develop a system of management that is consistently successful, mainly due to the paucity of basic neurophysiological data about PLP and its pathways in the central nervous system (CNS). Functional imaging offers a way of collecting information about the basic mechanisms and pathways of PLP from patients without the excessive risk of more invasive penetrating electrode studies or the questionable reliability of animal data. There have been very few studies that have looked at the direct effect of CNS stimulation on regional brain activation and correlation with the pain state. We describe two cases of PLP that have been satisfactorily treated with CNS stimulation (motor cortex and then periventricular gray in one and spinal cord in the other) and have been subjected to single photon emission computed tomography (SPECT) studies when in pain and then during stimulation with recorded pain relief. We found that regardless of the site of stimulation in the CNS, pain relief is associated with blood flow changes in similar areas of the brain, mainly the parietal and cingulate cortex and also in the thalamic nuclei and the central gray matter. Further studies of this kind should reveal more about the complex mechanisms of PLP and other forms of neuropathic pain.