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Symmetry lies at the heart of two-dimensional (2D) bioelectronics, determining material properties at the fundamental level. Breaking the symmetry allows emergent functionalities and effects. However, symmetry modulation in 2D bioelectronics and the resultant applications have been largely overlooked. Here, we devise an oxidized architectural MXene, referred to as oxidized MXene (OXene), that couples orbit symmetric breaking with inverse symmetric breaking to entitle the optimized interfacial impedance and Schottky-induced piezoelectric effects. The resulting OXene validates applications ranging from microelectrode arrays, gait analysis, active transistor matrix, and wireless signaling transmission, which enables high-fidelity signal transmission and reconfigurable logic gates. Furthermore, OXene interfaces were investigated in both rodent and porcine myocardium, featuring high-quality and spatiotemporally resolved physiological recordings, while accurate differentiated predictions, enabled via various machine learning pipelines. [ABSTRACT FROM AUTHOR]

The dynamics of N-methylpyrrole following excitation at wavelengths in the range 241.5-217.0 nm were studied using a combination of time-resolved photoelectron spectroscopy (TRPES), ab initio quantum dynamics calculations using the multi-layer multi-configurational time-dependent Hartree method, as well as high-level photoionization cross section calculations. Excitation at 241.5 and 236.2 nm results in population of the A2(πσ*) state, in agreement with previous studies. Excitation at 217.0 nm prepares the previously neglected B1(π3py) Rydberg state, followed by prompt internal conversion to the A2(πσ*) state. In contrast with the photoinduced dynamics of pyrrole, the lifetime of the wavepacket in the A2(πσ*) state was found to vary with excitation wavelength, decreasing by one order of magnitude upon tuning from 241.5 nm to 236.2 nm and by more than three orders of magnitude when excited at 217.0 nm. The order of magnitude difference in lifetimes measured at the longer excitation wavelengths is attributed to vibrational excitation in the A2(πσ*) state, facilitating wavepacket motion around the potential barrier in the N-CH3 dissociation coordinate. [ABSTRACT FROM AUTHOR]

The dynamics of pyrrole excited at wavelengths in the range 242-217 nm are studied using a combination of time-resolved photoelectron spectroscopy and wavepacket propagations performed using the multi-configurational time-dependent Hartree method. Excitation close to the origin of pyrrole's electronic spectrum, at 242 and 236 nm, is found to result in an ultrafast decay of the system from the ionization window on a single timescale of less than 20 fs. This behaviour is explained fully by assuming the system to be excited to the A2(πσ*) state, in accord with previous experimental and theoretical studies. Excitation at shorter wavelengths has previously been assumed to result predominantly in population of the bright A1(ππ*) and B2(ππ*) states. We here present time-resolved photoelectron spectra at a pump wavelength of 217 nm alongside detailed quantum dynamics calculations that, together with a recent reinterpretation of pyrrole's electronic spectrum [S. P. Neville and G. A. Worth, J. Chem. Phys. 140, 034317 (2014)], suggest that population of the B1(πσ*) state (hitherto assumed to be optically dark) may occur directly when pyrrole is excited at energies in the near UV part of its electronic spectrum. The B1(πσ*) state is found to decay on a timescale of less than 20 fs by both N-H dissociation and internal conversion to the A2(πσ*) state. [ABSTRACT FROM AUTHOR]

The effect of antisymmetric C-H stretching excitation of CH4 on the dynamics and reactivity of the O(1D) + CH4 → OH + CD3 reaction at the collision energy of 6.10 kcal/mol has been investigated using the crossed-beam and time-sliced velocity map imaging techniques. The antisymmetric C-H stretching mode excited CH4 molecule was prepared by direct infrared excitation. From the measured images of the CH3 products with the infrared laser on and off, the product translational energy and angular distributions were derived for both the ground and vibrationally excited reactions. Experimental results show that the vibrational energy of the antisymmetric stretching excited CH4 reagent is channeled exclusively into the vibrational energy of the OH co-products and, hence, the OH products from the excited-state reaction are about one vibrational quantum hotter than those from the ground-state reaction, and the product angular distributions are barely affected by the vibrational excitation of the CH4 reagent. The reactivity was found to be suppressed by the antisymmetric stretching excitation of CH4 for all observed CH3 vibrational states. The degree of suppression is different for different CH3 vibrational states: the suppression is about 40%-60% for the ground state and the umbrella mode excited CH3 products, while for the CH3 products with one quantum symmetric stretching mode excitation, the suppression is much less pronounced. In consequence, the vibrational state distribution of the CH3 product from the excited-state reaction is considerably different from that of the ground-state reaction. [ABSTRACT FROM AUTHOR]

Introduction: Effective pain control after video-assisted thoracic surgery (VATS) is critical because of the correlation between postoperative pain and recovery after surgery. Due to the limitations of traditional analgesic modalities, in this study, we present a method of placing a paravertebral catheter (PVC) or an intercostal catheter (ICC) in the sub-pleural space, followed by continuous ropivacaine injection by an infusion pump after surgery. Aim: To investigate the impact of continuous paravertebral nerve block and intercostal nerve block on postoperative pain control in patients who underwent two-port thoracic surgery. Material and methods: A total of 269 patients underwent various types of two-port VATS at Hwa Mei Hospital. Among them, we retrospectively compared paravertebral block versus intercostal nerve block to intravenous patient- controlled analgesia after VATS. Data regarding postoperative pain score on postoperative day 0, 1, 2, 3, and discharge day pain score, tramadol requirements, drainage duration, postoperative hospital stay, postoperative complications, and chronic pain 3 months after surgery were collected and analyzed. Results: Compared with the control group, patients who received a continuous nerve block, including the PVC group and ICC group, had a lower postoperative pain score (p < 0.001), shorter drainage duration (4.63 ±2.84 to 5.61 ±2.66 days, p = 0.004), reduced postoperative hospital stay (6.04 ±3.01 to 7.69 ±3.26 days, p < 0.001), and a reduced frequency of tramadol (0.95 ±1.27 1.79 ±2.13 times, p < 0.001). Additionally, there was no significant difference in chronic pain between groups. Conclusions: In our study, PVC and ICC appeared to be safe and effective analgesic techniques to reduce postoperative pain, thus shortening the duration of postoperative hospital stay and improving the satisfaction of patients. [ABSTRACT FROM AUTHOR]

Infrared spectroscopic study of neutral water clusters is crucial to understanding of the hydrogen-bonding networks in liquid water and ice. Here we report infrared spectra of size-selected neutral water clusters, (H2O)n (n = 3−6), in the OH stretching vibration region, based on threshold photoionization using a tunable vacuum ultraviolet free-electron laser. Distinct OH stretch vibrational fundamentals observed in the 3,500−3,600-cm−1 region of (H2O)5 provide unique spectral signatures for the formation of a noncyclic pentamer, which coexists with the global-minimum cyclic structure previously identified in the gas phase. The main features of infrared spectra of the pentamer and hexamer, (H2O)n (n = 5 and 6), span the entire OH stretching band of liquid water, suggesting that they start to exhibit the richness and diversity of hydrogen-bonding networks in bulk water. [ABSTRACT FROM AUTHOR]

It has long been predicted that oscillatory behavior exists in reactivity as a function of collision energy for heavy–light–heavy (HLH) chemical reactions in which a light atom is transferred between two heavy atoms or groups of atoms, but direct observation of such a behavior in bimolecular reactions remains a challenge. Here we report a joint theoretical and crossed-molecular-beam study on the Cl + CH4 → HCl + CH3 reaction. A distinctive peak at a collision energy of 0.15 eV for the CH3(v = 0) product was experimentally detected in the backward scattering direction. Detailed quantumdynamics calculations on a highly accurate potential energy surface revealed that this feature originates from the reactivity oscillation in this HLH polyatomic reaction. We anticipate that such reactivity oscillations exist in many HLH reactions involving polyatomic reagents. [ABSTRACT FROM AUTHOR]

Both laser-induced fluorescence and cavity ring-down spectral observations were made in the Schumann-Runge band system of oxygen, using a novel-type ultranarrow deep-UV pulsed laser source. From measurements on the very weak (0,0) band pressure broadening, pressure shift, and predissociation line-broadening parameters were determined for the B 3Σu-, v=0,Fi fine-structure components for various rotational levels in O2. The information content from these studies was combined with that of entirely independent measurements probing the much stronger (0,10), (0,19), and (0,20) Schumann-Runge bands involving preparation of vibrationally excited O2 molecules via photolysis of ozone. The investigations result in a consistent set of predissociation widths for the B 3Σu-, v=0 state of oxygen. [ABSTRACT FROM AUTHOR]

Recent molecular-beam experiments have probed the dynamics of the Rydberg-atom reaction, H(n)+D2→HD+D(n) at low collision energies. It was discovered that the rotationally resolved product distribution was remarkably similar to a much more limited data set obtained at a single scattering angle for the ion-molecule reaction H++D2→D++HD. The equivalence of these two problems would be consistent with the Fermi-independent-collider model (electron acting as a spectator) and would provide an important new avenue for the study of ion-molecule reactions. In this work, we employ a classical trajectory calculation on the ion-molecule reaction to facilitate a more extensive comparison between the two systems. The trajectory simulations tend to confirm the equivalence of the ion+molecule dynamics to that for the Rydberg-atom+molecule system. The theory reproduces the close relationship of the two experimental observations made previously. However, some differences between the Rydberg-atom experiments and the trajectory simulations are seen when comparisons are made to a broader data set. In particular, the angular distribution of the differential cross section exhibits more asymmetry in the experiment than in the theory. The potential breakdown of the classical model is discussed. The role of the “spectator” Rydberg electron is addressed and several crucial issues for future theoretical work are brought out. [ABSTRACT FROM AUTHOR]

Patients with Parkinson's disease (PD) generally have a higher proportion of suffering from mild cognitive impairment (MCI) than normal aged adults. This study aimed to identify the specific neuroanatomical alterations in early, drug-naive PD with MCI (PD-MCI) by comparing to those PD with normal cognition (PDNC) and healthy controls (HCs), which could help to elucidate the underlying neuropathology and facilitate the development of early therapeutic strategies for treating this disease. Structural MRI data of 237 early, drug-naive non-demented PD patients (classified as 61 PD-MCI and 176 PD-NC) and 69 HCs were included from Parkinson's Progression Markers Initiative (PPMI) database after data quality control. Within these data, a subset of 61 HCs and a subset of 61 PD-NC who were matched to the 61 PD-MCI group for age, gender, and education-level were selected to further eliminate the sample size effect. The gray matter (GM) volume changes between groups were analyzed using voxel-based morphometry (VBM). Furthermore, correlations between GM volume alterations and neuropsychological performances and non-cognitive assessments (including olfactory performance) were further examined. Compared to HC, patients with PD-NC and PD-MCI commonly exhibited atrophies in the bilateral amygdala (AM) and the left primary motor cortex (M1). Patients with PD-MCI exclusively exhibited atrophy in the right entorhinal cortex (ENT) compared to PD-NC. Significantly negative correlations were found between GM loss in the bilateral AM and olfactory performance in all PD patients, and between ENT loss and memory performance in PD-MCI. The findings suggest that the right ENT atrophy may subserve as a biomarker in early, drug-naive PD-MCI, which shed light on the neural underpinnings of the disease and provide new evidence on differentiating the neuroanatomical states between PD-MCI and PD-NC. [ABSTRACT FROM AUTHOR]

Hydroxyl radicals (OH) play a central role in the interstellar medium. Here, we observe highly rotationally excited OH radicals with energies above the bond dissociation energy, termed OH “super rotors”, from the vacuum ultraviolet photodissociation of water. The most highly excited OH(X) super rotors identified at 115.2 nm photolysis have an internal energy of 4.86 eV. A striking enhancement in the yield of vibrationally-excited OH super rotors is detected when exciting the bending vibration of the water molecule. Theoretical analysis shows that bending excitation enhances the probability of non-adiabatic coupling between the ~B and ~X states of water at collinear O–H–H geometries following fast internal conversion from the initially excited ~D state. The present study illustrates a route to produce extremely rotationally excited OH(X) radicals from vacuum ultraviolet water photolysis, which may be related to the production of the highly rotationally excited OH(X) radicals observed in the interstellar medium. [ABSTRACT FROM AUTHOR]

Function transformation is a common approach to improve accuracy of the grey forecasting model. Discrete GM(1,1) model (DGM(1,1)) is an important member of the family of grey system models. To improve the fitting accuracy of an oscillating sequence, the variable speed translational operator-based DGM(1,1) model was built and the fitting accuracy was compared with those of other methods in this study. Furthermore, to determine how variable speed transitional operator affect predictive accuracy of the DGM(1,1) model, the empirical analysis of property for variable speed translational operator was conducted. The results demonstrated that the proposed variable speed transitional operator to reduce second-order step-wise variance and second-order stepwise ratio deviation were effective in improving accuracy of DGM(1,1) model for the oscillating sequence. It will supplement the criterion of function transformation and widen the application range of the grey forecasting model. [ABSTRACT FROM AUTHOR]

Purpose: Automatic brain image labeling is highly demanded in the field of medical image analysis. Multiatlas-based approaches are widely used due to their simplicity and robustness in applications. Also, random forest technique is recognized as an efficient method for labeling, although there are several existing limitations. In this paper, the authors intend to address those limitations by proposing a novel framework based on the hierarchical learning of atlas forests. Methods: Their proposed framework aims to train a hierarchy of forests to better correlate voxels in the MR images with their corresponding labels. There are two specific novel strategies for improving brain image labeling. First, different from the conventional ways of using a single level of random forests for brain labeling, the authors design a hierarchical structure to incorporate multiple levels of forests. In particular, each atlas forest in the bottom level is trained in accordance with each individual atlas, and then the bottom-level forests are clustered based on their capabilities in labeling. For each clustered group, the authors retrain a new representative forest in the higher level by using all atlases associated with the lower-level atlas forests in the current group, as well as the tentative label maps yielded from the lower level. This clustering and retraining procedure is conducted iteratively to yield a hierarchical structure of forests. Second, in the testing stage, the authors also present a novel atlas forest selection method to determine an optimal set of atlas forests from the constructed hierarchical structure (by disabling those nonoptimal forests) for accurately labeling the test image. Results: For validating their proposed framework, the authors evaluate it on the public datasets, including Alzheimer's disease neuroimaging initiative, Internet brain segmentation repository, and LONI LPBA40. The authors compare the results with the conventional approaches. The experiments show that the use of the two novel strategies can significantly improve the labeling performance. Note that when more levels are constructed in the hierarchy, the labeling performance can be further improved, but more computational time will be also required. Conclusions: The authors have proposed a novel multiatlas-based framework for automatic and accurate labeling of brain anatomies, which can achieve accurate labeling results for MR brain images. [ABSTRACT FROM AUTHOR]

We analyze simple dynamical network models which describe the limited capacity of nodes to process the input information. For a proper range of their parameters, the information flow pattern in these models is characterized by exponential distribution of the incoming information and a fat-tailed distribution of the outgoing information, as a signature of the law of diminishing marginal returns. We apply this analysis to effective connectivity networks from human EEG signals, obtained by Granger Causality, which has recently been given an interpretation in the framework of information theory. From the distributions of the incoming versus the outgoing values of the information flow it is evident that the incoming information is exponentially distributed whilst the outgoing information shows a fat tail. This suggests that overall brain effective connectivity networks may also be considered in the light of the law of diminishing marginal returns. Interestingly, this pattern is reproduced locally but with a clear modulation: a topographic analysis has also been made considering the distribution of incoming and outgoing values at each electrode, suggesting a functional role for this phenomenon. [ABSTRACT FROM AUTHOR]

The non-resonant dynamic Stark effect is a powerful and general way of manipulating ultrafast processes in atoms, molecules, and solids with exquisite precision. We discuss the physics behind this effect, and demonstrate its efficacy as a method of control in a variety of systems. These applications range from the control of molecular rotational dynamics to the manipulation of chemical reaction dynamics, and from the suppression of vacuum fluctuation effects in coherent preparation of matter, to the dynamic generation of bandwidth for storage of broadband quantum states of light. [ABSTRACT FROM AUTHOR]

Background: Studies for infants are usually hindered by the insufficient image contrast, especially for neonates. Prior knowledge, in the form of atlas, can provide additional guidance for the data processing such as spatial normalization, label propagation, and tissue segmentation. Although it is highly desired, there is currently no such infant atlas which caters for all these applications. The reason may be largely due to the dramatic early brain development, image processing difficulties, and the need of a large sample size. Methodology: To this end, after several years of subject recruitment and data acquisition, we have collected a unique longitudinal dataset, involving 95 normal infants (56 males and 39 females) with MRI scanned at 3 ages, i.e., neonate, 1-year-old, and 2-year-old. State-of-the-art MR image segmentation and registration techniques were employed, to construct which include the templates (grayscale average images), tissue probability maps (TPMs), and brain parcellation maps (i.e., meaningful anatomical regions of interest) for each age group. In addition, the longitudinal correspondences between agespecific atlases were also obtained. Experiments of typical infant applications validated that the proposed atlas outperformed other atlases and is hence very useful for infant-related studies. Conclusions: We expect that the proposed infant 0-1-2 brain atlases would be significantly conducive to structural and functional studies of the infant brains. These atlases are publicly available in our website, http://bric.unc.edu/ideagroup/ free-softwares/. [ABSTRACT FROM AUTHOR]

Crossed molecular beam experiments and accurate quantum scattering calculations have been carried out for the polyatomic H + CD4 → HD + CD3 reaction. Unprecedented agreement has been achieved between theory and experiments on the energy dependence of the integral cross section in a wide collision energy region that first rises and then falls considerably as the collision energy increases far over the reaction barrier for this simple hydrogen abstraction reaction. Detailed theoretical analysis shows that at collision energies far above the barrier the incoming H-atom moves soquickly that the heavier D-atom on CD4 cannot concertedly follow it to form the HD product, resulting in the decline of reactivity with the increase of collision energy. We propose that this is also the very mechanism, operating in many abstraction reactions, which causes the differential cross section in the backward direction to decrease substantially or even vanish at collision energies far above the barrier height. [ABSTRACT FROM AUTHOR]

We propose a novel diffusion tensor imaging (DTI) registration algorithm, called fast tensor image morphing for elastic registration (F-TIMER). F-TIMER leverages multiscale tensor regional distributions and local boundaries for hierarchically driving deformable matching of tensor image volumes. Registration is achieved by utilizing a set of automatically determined structural landmarks, via solving a soft correspondence problem. Based on the estimated correspondences, thin-plate splines are employed to generate a smooth, topology preserving, and dense transformation, and to avoid arbitrary mapping of nonlandmark voxels. To mitigate the problem of local minima, which is common in the estimation of high dimensional transformations, we employ a hierarchical strategy where a small subset of voxels with more distinctive attribute vectors are first deployed as landmarks to estimate a relatively robust low-degrees-of-freedom transformation. As the registration progresses, an increasing number of voxels are permitted to participate in refining the correspondence matching. A scheme as such allows less conservative progression of the correspondence matching towards the optimal solution, and hence results in a faster matching speed. Compared with its predecessor TIMER, which has been shown to outperform state-of-the-art algorithms, experimental results indicate that F-TIMER is capable of achieving comparable accuracy at only a fraction of the computation cost. [ABSTRACT FROM AUTHOR]

The first fully allowed spectroscopic transition in O2 is the [image omitted] transition comprising the well-known Schumann-Runge bands and continuum. We report a velocity-map imaging study in which the O(1D) angular momentum polarisation and O(3P) spin-orbit branching ratios arising from this process have been measured. We show that direct 157 nm excitation into the Schumann-Runge continuum leads to extremely strong angular momentum polarisation in the O(1D) product. Comparison with previous studies indicates that this is a general feature of dissociation via the B state. The fine structure branching ratios in the co-fragment O(3PJ=2,1,0) were measured to be 88.5 ± 1.6 : 9.7 ± 1.4 : 1.9 ± 0.4. Based on a consideration of the Massey parameter for the system, the data were modelled using theoretical calculations based on adiabatic and diabatic models of the dissociation. While both models were able to describe some aspects of the dissociation accurately, neither was able to predict both the fine structure branching ratios of the O(3P) products and the O(1D2) alignment. We have also investigated O(1D2) alignment arising from 203.8 and 205.5 nm photodissociation via the [image omitted] state of O2 vibrationally excited to v=6-11. As in the 157 nm photodissciation of vibrationally ground state O2, strong polarisation of the O(1D2) photofragments is observed. [ABSTRACT FROM AUTHOR]

This paper presents a learning-based method for deformable registration of magnetic resonance (MR) brain images. There are two novelties in the proposed registration method. First, a set of best-scale geometric features are selected for each point in the brain, in order to facilitate correspondence detection during the registration procedure. This is achieved by optimizing an energy function that requires each point to have its best-scale geometric features consistent over the corresponding points in the training samples, and at the same time distinctive from those of nearby points in the neighborhood. Second, the active points used to drive the brain registration are hierarchically selected during the registration procedure, based on their saliency and consistency measures. That is, the image points with salient and consistent features (across different individuals) are considered for the initial registration of two images, while other less salient and consistent points join the registration procedure later. By incorporating these two novel strategies into the framework of the HAMMER registration algorithm, the registration accuracy has been improved according to the results on simulated brain data, and also visible improvement is observed particularly in the cortical regions of real brain data. [ABSTRACT FROM AUTHOR]

The low velocity impact responses of shape memory alloy (SMA) reinforced composite beams were analyzed by employing the finite element method. The finite element dynamic equation was solved by the Neumark direct integration method, the impact contact force was determined using the Hertzian contact law, and the influence of SMA fibers on stiffness matrix is studied. Numerical results show that the SMA fibers can effectively improve the low velocity impact response property of composite beam. [ABSTRACT FROM AUTHOR]