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"Liu, Hao"
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In a future where the world is roughly divided into two factions, the Pacific League of Nations and the Atlantic Division of Nations, tensions are high as each side waits for the other to make a move. But neither side is prepared for a powerful third party that has apparently been an influential presence on Earth for thousands of years, and just might be making a reappearance very soon. With the realization that a highly intelligent alien race has been trying to send them messages, three rising scientists within the Pacific League of Nations form an uneasy alliance. Fueled by a curiosity to have their questions answered and a fear that other factions within their rival Atlantic Division of Nations would opt for a more aggressive and potentially disastrous military response, the three race to secure first contact with this extraterrestrial life they aren't quite convinced is a threat. Bolstered by recent evidence of alien visitations in the distant past, the three scientific minds must solve puzzles rooted within human antiquity, face off with their personal demons, and discover truths of the universe.
Book
Unifying the order and disorder dynamics in photoexcited VO2
Photoinduced phase transition (PIPT) is always treated as a coherent process, but ultrafast disordering in PIPT is observed in recent experiments. Utilizing the real-time time-dependent density functional theory method, here we track the motion of individual vanadium (V) ions during PIPT in VO₂ and uncover that their coherent or disordered dynamics can be manipulated by tuning the laser fluence. We find that the photoexcited holes generate a force on each V–V dimer to drive their collective coherent motion, in competing with the thermal-induced vibrations. If the laser fluence is so weak that the photoexcited hole density is too low to drive the phase transition alone, the PIPT is a disordered process due to the interference of thermal phonons. We also reveal that the photoexcited holes populated by the V–V dimerized bonding states will become saturated if the laser fluence is too strong, limiting the timescale of photoinduced phase transition.
Journal Article
Partially sintered copper‒ceria as excellent catalyst for the high-temperature reverse water gas shift reaction
For high-temperature catalytic reaction, it is of significant importance and challenge to construct stable active sites in catalysts. Herein, we report the construction of sufficient and stable copper clusters in the copper‒ceria catalyst with high Cu loading (15 wt.%) for the high-temperature reverse water gas shift (RWGS) reaction. Under very harsh working conditions, the ceria nanorods suffered a partial sintering, on which the 2D and 3D copper clusters were formed. This partially sintered catalyst exhibits unmatched activity and excellent durability at high temperature. The interaction between the copper and ceria ensures the copper clusters stably anchored on the surface of ceria. Abundant in situ generated and consumed surface oxygen vacancies form synergistic effect with adjacent copper clusters to promote the reaction process. This work investigates the structure-function relation of the catalyst with sintered and inhomogeneous structure and explores the potential application of the sintered catalyst in C1 chemistry.
Constructing stable active sites in catalysts for high temperature catalytic reactions remains challenging. Here, the authors manage to make stable copper clusters in the copper‒ceria catalyst with high Cu loading (15 wt.%) for the high-temperature reverse water gas shift reaction.
Journal Article
Adversarial Attacks and Defenses in Images, Graphs and Text: A Review
Deep neural networks (DNN) have achieved unprecedented success in numerous machine learning tasks in various domains. However, the existence of adversarial examples raises our concerns in adopting deep learning to safety-critical applications. As a result, we have witnessed increasing interests in studying attack and defense mechanisms for DNN models on different data types, such as images, graphs and text. Thus, it is necessary to provide a systematic and comprehensive overview of the main threats of attacks and the success of corresponding countermeasures. In this survey, we review the state of the art algorithms for generating adversarial examples and the countermeasures against adversarial examples, for three most popular data types, including images, graphs and text.
Journal Article
Fuzzy logic based evaluation of environmental perception and vitality of public space in old residential area
This study proposes a novel FL-based framework for evaluating the vitality of public spaces in old residential areas. Unlike existing models, which often rely on rigid quantitative metrics or overly generalized spatial assessments, our approach integrates environmental perception with spatial vitality using a multi-criteria FL decision-making model. The model introduces a systematic way to capture both physical and social dimensions of public spaces, including spatial form, accessibility, facility layout, visual openness, and greenery. These are translated into evaluative rules through FL, allowing for nuanced assessments of underutilized or aging urban spaces. Current urban studies often mention vitality and perception but lack formalized methods for measuring them in historical contexts. Our research fills this theoretical gap by offering a structured, adaptable model that incorporates local geographic and social variables. Through empirical analysis and expert validation, the model demonstrates strong alignment with observed urban patterns and design outcomes. This study contributes to the field of urbanism by offering a scalable and transferable methodology for revitalizing legacy neighborhoods, guiding both policy and design toward more livable, inclusive urban environments.
Journal Article
Realizing efficient blue and deep-blue delayed fluorescence materials with record-beating electroluminescence efficiencies of 43.4
As promising luminescent materials for organic light-emitting diodes (OLEDs), thermally activated delayed fluorescence materials are booming vigorously in recent years, but robust blue ones still remain challenging. Herein, we report three highly efficient blue and deep-blue delayed fluorescence materials comprised of a weak electron acceptor chromeno[3,2-c]carbazol-8(5H)-one with a rigid polycyclic structure and a weak electron donor spiro[acridine-9,9’-xanthene]. They hold distinguished merits of excellent photoluminescence quantum yields (99%), ultrahigh horizontal transition dipole ratios (93.6%), and fast radiative transition and reverse intersystem crossing, which furnish superb blue and deep-blue electroluminescence with Commission Internationale de I’Eclairage coordinates (CIE
x,y
) of (0.14, 0.18) and (0.14, 0.15) and record-beating external quantum efficiencies (
η
ext
s) of 43.4% and 41.3%, respectively. Their efficiency roll-offs are successfully reduced by suppressing triplet-triplet and singlet-singlet annihilations. Moreover, high-performance deep-blue and green hyperfluorescence OLEDs are achieved by utilizing these materials as sensitizers for multi-resonance delayed fluorescence dopants, providing state-of-the-art
η
ext
s of 32.5% (CIE
x,y
= 0.14, 0.10) and 37.6% (CIE
x,y
= 0.32, 0.64), respectively, as well as greatly advanced operational lifetimes. These splendid results can surely inspire the development of blue and deep-blue luminescent materials and devices.
Thermally activated delayed fluorescence materials are important for the development of OLED materials but the development of robust blue emitting materials remains challenging. Here, the authors report three highly efficient blue and deepblue delayed fluorescence materials demonstrating excellent electroluminescence performance.
Journal Article
N-soliton, Hth-order breather, hybrid and multi-pole solutions for a generalized variable-coefficient Gardner equation with an external force in a plasma or fluid
In this paper, we investigate a generalized variable-coefficient Gardner equation with an external force in a plasma or fluid. Via the Hirota method, we obtain certain bilinear forms and N-soliton solutions, where N is a positive integer. We also derive the Hth-order breather and hybrid solutions through the complex conjugated transformations, where H is a positive integer. Moreover, multi-pole solutions are constructed with the limit method. Multi-soliton, breather-breather, soliton-breather and multi-pole interactions are studied. Influences of the external force and variable coefficients on the solutions are discussed analytically and graphically. For those nonlinear waves: (i) the external force affects the backgrounds and velocities; (ii) the damping coefficient affects the amplitudes, widths and velocities; (iii) the dispersive and dissipative coefficients affect the characteristic lines and velocities.
Journal Article
Association of ocular diseases with schizophrenia, bipolar disorder, and major depressive disorder: a retrospective case-control, population-based study
Background
Psychiatric disorders and ocular neurovascular diseases may share a similar pathophysiological route of vascular structures or neurological changes. The aim of this study is to investigate the association between ocular neurovascular diseases and the risk of major psychiatric disorders.
Methods
This was a retrospective case–control, population-based study including patients aged ≥20 and were diagnosed between 1997 and 2013. Ocular neurovascular diseases diagnosed between 1997 and 2006 and newly diagnosed psychiatric disorders including bipolar disorder (BD), major depressive disorder (MDD), and schizophrenia between 2007 and 2013 were registered. Patients were propensity-score matched with control groups without psychiatric disorders in each cohort based on selected covariates.
Results
A total of one million sampled patients in the database were categorized based on their diagnoses; 2243 (37.4% men) were categorized into the BD group, 10,110 (35.2% men) into the MDD group, and 1623 (43.1% men) into the schizophrenia group. In the BD group, all glaucoma (OR 1.49, [1.18–1.89]), open-angle glaucoma (OR 2.08, [1.34–3.24]), and closed-angle glaucoma (OR 2.12, [1.36–3.33]) showed statistical significance of risk. In the MDD group, age-related macular degeneration (OR 1.33, [1.13–1.57]), all glaucoma (OR 1.24, [1.11–1.37]), open-angle glaucoma (OR 1.47, [1.21–1.80]), and dry eye syndrome (OR 1.22, [1.13–1.31]) were associated with a significantly higher risk. In the schizophrenia group, only all glaucoma (OR 1.47, [1.02–2.11]), glaucoma suspect (OR 1.88, [1.01–3.49]), and open-angle glaucoma (OR 2.19, [1.13–4.26]) showed statistical significance.
Conclusions
In this population-based study, ocular neurovascular diseases, especially glaucoma, were associated with increased risks of BD, MDD, and schizophrenia.
Journal Article
Enhancing the bioconversion of phytosterols to steroidal intermediates by the deficiency of kasB in the cell wall synthesis of Mycobacterium neoaurum
Background
The bioconversion of phytosterols into high value-added steroidal intermediates, including the 9
α
-hydroxy-4-androstene-3,17-dione (9-OHAD) and 22-hydroxy-23,24-bisnorchol-4-ene-3-one (4-HBC), is the cornerstone in steroid pharmaceutical industry. However, the low transportation efficiency of hydrophobic substrates into mycobacterial cells severely limits the transformation. In this study, a robust and stable modification of the cell wall in
M. neoaurum
strain strikingly enhanced the cell permeability for the high production of steroids.
Results
The deletion of the nonessential
kasB
, encoding a β-ketoacyl-acyl carrier protein synthase, led to a disturbed proportion of mycolic acids (MAs), which is one of the most important components in the cell wall of
Mycobacterium neoaurum
ATCC 25795. The determination of cell permeability displayed about two times improvement in the
kasB
-deficient strain than that of the wild type
M. neoaurum
. Thus, the deficiency of
kasB
in the 9-OHAD-producing strain resulted in a significant increase of 137.7% in the yield of 9
α
-hydroxy-4-androstene-3,17-dione (9-OHAD). Ultimately, the 9-OHAD productivity in an industrial used resting cell system was reached 0.1135 g/L/h (10.9 g/L 9-OHAD from 20 g/L phytosterol) and the conversion time was shortened by 33%. In addition, a similar self-enhancement effect (34.5%) was realized in the 22-hydroxy-23,24-bisnorchol-4-ene-3-one (4-HBC) producing strain.
Conclusions
The modification of
kasB
resulted in a meaningful change in the cell wall mycolic acids. Deletion of the
kasB
gene remarkably improved the cell permeability, leading to a self-enhancement of the steroidal intermediate conversion. The results showed a high efficiency and feasibility of this construction strategy.
Journal Article
Research and Prevention of Harmful Gases in Special Structures of Urban Deep Drainage Systems
Wastewater remaining in pipes for extended periods can create anaerobic environments, fostering the growth of anaerobic bacteria and producing harmful gases such as methane and hydrogen sulfide. Additionally, certain structures within drainage systems, such as drop shafts and vertical shafts, induce turbulent flow, causing the release of dissolved harmful gases, which pose significant risks to public health and urban infrastructure. This study focused on the investigation and analysis of vertical shafts with helical tray structures in drainage systems. Using ANSYS 2021 R2 software, simulations of the shafts were conducted by employing the standard k-ε turbulence model and Eulerian multiphase flow method to simulate the shaft’s operation and obtain various parameters of hydrogen sulfide release. Concurrently, a scale model constructed in the laboratory was used to study and analyze the release of hydrogen sulfide gas dissolved in water from this type of structure. Combining the simulation and laboratory experiments, the hydrogen sulfide gas release rate from water in this structure was 0.05–0.4%. This research provides a reference for the study and control of hydrogen sulfide gas release.
Journal Article