The microstructural abnormalities of cingulum was related to patients with mild cognitive impairment: a diffusion kurtosis imaging study.

OBJECTIVE: Our study aimed to investigate the correlations between microstructural changes of cingulum and patients with mild cognitive impairment (MCI) by diffusion kurtosis imaging (DKI) technique. METHOD: A total of 104 patients with cerebral small vessel diseases (cSVD) were retrospectively enrolled in this study. According to Montreal Cognitive Assessment Scale (MoCA) scores, these patients were divided into MCI group (n = 59) and non-MCI group (n = 45). The general clinical data was collected and analyzed. The regions of interests (ROIs) were selected for investigation in cingulum. The values of DKI parameters were measured in each ROI and compared between the two groups, the correlations between DKI parameters and MoCA scores were examined. RESULTS: Compared to non-MCI group, MCI patients had more severe white matter hyperintensities (WMHs) (P = 0.038) and lower MoCA scores (P < 0.01). MCI patients showed significantly decreased fractional anisotropy (FA), axial kurtosis (AK), mean kurtosis (MK), radial kurtosis (RK), and kurtosis fractional anisotropy (KFA) in the left cingulum in the cingulated cortex (CgC) region (all P < 0.0125). In the left CgC region, FA, AK, MK, RK, and KFA were positively correlated with MoCA scores (r = 0.348, 0.409, 0.310, 0.441, 0.422, all P < 0.001). Meanwhile, FA, AK, MK, RK, and KFA were also positively correlated with MoCA scores (r = 0.338, 0.352, 0.289, 0.380, 0.370, all P < 0.001) in the right CgC region. CONCLUSION: DKI technique could be used to explore the microstructural changes of cingulum in MCI patients and DKI-derived parameters might be feasible to evaluate MCI patients.

Air pollution outcomes, land misallocation, and the transmission through urban sprawl.

Air pollution is an inevitable negative environmental externality in the process of industrialization and urbanization in countries around the world. Land misallocation in the process of urbanization and industrialization and the resulting urban sprawl exacerbates the above problems. As a major country in the stage of rapid urbanization and industrialization, China also faces severe air pollution problems. Therefore, this paper will systematically study the impact of land misallocation and urban sprawl on air pollution. We first set up the utility maximization problem of each economic entity in the process of land misallocation in the mathematical model, and form a general equilibrium theory model to analyze the relationship between land misallocation, urban sprawl and air pollution, and then put forward the research hypotheses. We further use the big data of land market transactions of China Land Market Network and LandScan global population data to build the land misallocation index and urban sprawl index respectively, and use an extended mediating effect model to empirically test the hypotheses. The results suggest that the effect of land misallocation on air pollution is significantly positive, and the impact of land misallocation on urban sprawl largely depends on the return rate of land relative to labor (RRIRL). When the RRIRL is relatively low, the impact is weak, or even has a negative effect to some extent. At this time, low transportation costs are conducive to reducing air pollution. On the contrary, when the RRIRL is relatively high, land misallocation has a significant role in promoting urban sprawl. At this time, high traffic costs are conducive to reducing air pollution. In addition, we also find that there is an inverted U-shaped relationship between urban sprawl and air pollution. When the urban sprawl level is low, its impact on air pollution increases with the increase of its level, but once it exceeds a specific node, the impact will decrease. Based on the characteristics of the relationship among land misallocation, urban sprawl and air pollution under different RRIRL, we summarize four environmentally friendly urban development paths. We bring the land bid rent theory and environmental pollution research into a same theoretical model framework, which provides a modeling idea and research perspective with a micro-foundation for subsequent research on land misallocation. We integrate the research conclusions of existing literature and unify them under the research frameworks concerning different RRIRL in the empirical results, which greatly improving their applicability. The four urban development paths summarized in this paper will also provide inspiration for future researchers and policy makers.

Porous Cyclodextrin Polymer Enables Dendrite-Free and Ultra-Long Life Solid-State Zn-I2 Batteries.

Zn-I2 batteries have attracted attention due to their low cost, safety, and environmental friendliness. However, their performance is still limited by the irreversible growth of Zn dendrites, hydrogen evolution reactions, corrosion, and shuttle effect of polyiodide. In this work, we have prepared a new porous polymer (CD-Si) by nucleophilic reaction of ß-cyclodextrin with SiCl4 , and CD-Si is applied to the solid polymer electrolyte (denoted PEO/PVDF/CD-Si) to solve above-mentioned problems. Through the anchoring of the CD-Si, a conductive network with dual transmission channels was successfully constructed. Due to the non-covalent anchoring effect, the ionic conductivity of the solid polymer electrolytes (SPE) can reach 1.64×10-3  S cm-1 at 25 °C. The assembled symmetrical batteries can achieve highly reversible dendrite-free galvanizing/stripping (stable cycling for 7500 h at 5 mA cm-2 and 1200 h at 20 mA cm-2 ). The solid-state Zn-I2 battery shows an ultra-long life of over 35,000 cycles at 2 A g-1 . Molecular dynamics simulations are performed to elucidate the working mechanism of CD-Si in the polymer matrix. This work provides a novel strategy towards solid electrolytes for Zn-I2 batteries.

Strain analysis and engineering in halide perovskite photovoltaics.

Halide perovskites are a compelling candidate for the next generation of clean-energy-harvesting technologies owing to their low cost, facile fabrication and outstanding semiconductor properties. However, photovoltaic device efficiencies are still below practical limits and long-term stability challenges hinder their practical application. Current evidence suggests that strain in halide perovskites is a key factor in dictating device efficiency and stability. Here we outline the fundamentals of strain within halide perovskites relevant to photovoltaic applications and rationalize approaches to characterize the phenomenon. We examine recent breakthroughs in eliminating the adverse impacts of strain, enhancing both device efficiencies and operational stabilities. Finally, we discuss further challenges and outline future research directions for placing stress and strain studies at the forefront of halide perovskite research. An extensive understanding of strain in halide perovskites is needed, which would allow effective strain management and drive further enhancements in efficiencies and stabilities of perovskite photovoltaics.

Low-dose antiplatelet therapy survey after intracerebral hemorrhage in China: a retrospective hospital-based study.

Restarting of antiplatelet therapy (AT) for patients with a history of intracerebral hemorrhage (ICH) is still a clinical dilemma in China. We aimed to investigate the association between low-dose AT and the long-term clinical outcome in Chinese ICH patients. A total of 312 patients with a history of ICH were retrospectively enrolled and followed. The ischemic vascular events, recurrent ICH, and all-cause death were reviewed retrospectively. We explored the predictors of ischemic vascular events and recurrent ICH from all patients using Cox proportional hazard regression model. One hundred fifty-one (48.4%) patients were treated with low-dose AT, and the median duration of follow-up was 4.0 years (interquartile range, 2.5-5 years). Compared to 30 (19.8%) of 151 participants who restarted low-dose AT had ischemic vascular events, 51 (31.7%) of 161 participants who did not receive AT showed ischemic vascular events (p=0.025). Eighteen (11.9%) of 151 participants treated with low-dose AT had recurrent ICH and 21 (13.0%) of 161 in non-AT participants (p=0.830). Cox regression analysis also showed that diabetes mellitus was an independent risk factor for ischemic vascular events (p=0.029). Uncontrolled blood pressure (BP) was independently associated with the risk for both ischemic vascular events (p=0.025) and recurrent ICH (p=0.001). Atrial fibrillation (AF) was an independent risk factor for recurrent ICH among patients with a history of ICH (p=0.018). In a Chinese population of patients with predominantly deep, mild to moderate severity ICH, restarting of low-dose AT at a median of 6.2 months was associated with a lower risk of ischemic vascular events without increased risk of recurrent ICH.

Demographic and morphological characteristics associated with rupture status of anterior communicating artery aneurysms.

The aim of this study is to characterize demographic and morphologic characteristics of aneurysms located in the anterior communicating artery (ACoA) and to investigate possible associations between these characteristics and aneurysm rupture. We investigated 112 consecutive patients (72 ruptured and 40 unruptured) with ACoA aneurysms from a single-center database. The effects of demographic and morphologic characteristics on the risk of rupture in ACoA aneurysms were tested using univariate and multivariate logistic regression analyses, respectively. We found that larger size, greater size ratio, larger flow angle, irregular shape, and smoking of the patient were associated with the rupture of ACoA aneurysms based on univariate analysis. Size ratio (OR = 3.890, P = 0.003), irregular shape (OR = 1.068, P = 0.001), flow angle (OR = 1.054, P = 0.001), and current smoking (OR = 4.435, P = 0.009) were the strongest factors related to ruptured ACoA aneurysms based on multivariate logistic regression analysis. The areas under the curves for the flow angle and size ratio were 0.742 (95% CI 0.646-0.838; P = 0.001) and 0.736 (95% CI 0.621-0.796; P = 0.001), respectively. The strongest risk factors for rupture include size ratio, irregular shape, flow angle, and current smoking. These features should be taken into consideration to aid in the prediction of the rupture risk of ACoA aneurysms.

Polar-Group Activated Isospecific Coordination Polymerization of ortho-Methoxystyrene: Effects of Central Metals and Ligands.

Stereoselective polymerization of polar vinyl monomers has been a long-standing challenge because the employed transition-metal catalysts are easily poisoned by polar groups of monomers. In this contribution, a series of ß-diketiminato rare-earth metal complexes 1-5 (L1-5 Ln(CH2 SiMe3 )2 (THF)n , Ln=Gd-Lu, Y, and Sc) were successfully synthesized. In combination with AliBu3 and [Ph3 C][B(C6 F5 )4 ], complexes 1 c(Tb)-1 g(Tm) exhibited high activities and excellent isoselectivities for the polymerization of ortho-methoxystyrene (oMOS), in which, the polar methoxy group of oMOS did not poison but activated the polymerization through σ-π chelation to the active species together with the vinyl group. Moreover, the large Gd-attached precursor 1 b showed a higher activity, albeit with a slightly decreased isoselectivity. The small Sc-attached precursor 1 i was completely inert. Meanwhile, the spatial steric arrangement and the coordination mode of the ß-diketiminato ligand could clearly affect and even block oMOS polymerization. This work sheds new light on the coordination polymerization of polar monomers.

Mechanism and Effect of Polar Styrenes on Scandium-Catalyzed Copolymerization with Ethylene.

Copolymerization of ethylene (E) and polar vinyl monomers remains a problem because E propagation is hindered. Herein, for the first time, we report the copolymerization of E and polar styrenes (SR ) by using an oxophilic scandium catalyst that exhibits higher turnover frequencies than both E and SR homopolymerizations when R is an electron-withdrawing group. This positive comonomer effect was elucidated through computing reaction profiles of E/SF copolymerization at the DFT (B3PW91) level of theory. It reveals that the secondary interaction between Sc3+ and phenyl of the last and penultimate inserted SF units leads to a decrease of the E insertion barrier, because the electron-withdrawing substituent enhances the electrophilicity of Sc3+ by an inductive effect mediated by the secondary interaction. After three consecutive insertions of the E units, the secondary interaction is lost and the SF insertion is kinetically preferred over the E insertion. This process is in line with the NMR spectrum analyses which show that the resultant copolymers mainly contain SR (E)x SR sequences where x≤3.

Rapid Syndiospecific (Co)Polymerization of Fluorostyrene with High Monomer Conversion.

Fluoromonomers are difficult to polymerize through a coordination mechanism owing to the strong chelation between fluorine and catalysts and the electron-deficient double-bond. We report herein the unprecedented polymerization of para-fluorostyrene (pFS) with excellent activity (1.12×107  g molLn-1 h-1 ), distinguished syndioselectivity (rrrr >99 %) and high conversion (98.4 %) using rare-earth-metal catalysts bearing a pyridyl methylene fluorenyl ligand. DFT calculations reveal polar fluorine loses overwhelming coordination priority to the active central metal ion due to the sterically bulky and electron-donating CGC-ligand, thus its power of poisoning the active species is dramatically weakened. Based on this, copolymerization of pFS and styrene (St) has been successfully achieved with high activity and controllable pFS insertion. Conversely, the unlinked half-sandwich rare-earth-metal system shows relatively lower activity, because both the transition-states and intermediates incorporate a µ1 -F chelated pFS.

Stereoselective Copolymerization of Unprotected Polar and Nonpolar Styrenes by an Yttrium Precursor: Control of Polar-Group Distribution and Mechanism.

Styrene underwent unprecedented coordination-insertion copolymerization with naked polar monomers (ortho-/meta-/para-methoxystyrene) in the presence of a pyridyl methylene fluorenyl yttrium catalyst. High activity (1.26×106  g molY-1 h-1 ) and excellent syndioselectivity were observed, and high-molecular-weight copolymers (24.6×104  g mol-1 ) were obtained. The insertion rate of the polar monomers could be adjusted in the full range of 0-100 % simply by changing the loading of the polar styrene monomer. Strikingly, the copolymers had tapered, gradient, and even random sequence distributions, depending on the position of the polar methoxy group on the phenyl ring and thus on its mode of coordination to the active metal center, as shown by tracking the polymerization process and DFT calculations.

Highly isoselective coordination polymerization of ortho-methoxystyrene with ß-diketiminato rare-earth-metal precursors.

Stereoselective coordination/insertion polymerization of the polar ortho-methoxystyrene has been achieved for the first time by using the cationic ß-diketiminato rare-earth-metal species. High activity and excellent isoselectivity (mmmm>99 %) were acheived. The unmasked Lewis-basic methoxy group does not poison the Lewis-acidic metal center, but instead activates the polymerization through σ-π chelation to the active species together with the vinyl group, thus lower the coordination and activation energies as compared with those of styrene derivatives lacking the methoxy group.

Lutetium-methanediide-alkyl complexes: synthesis and chemistry.

The first four-coordinate methanediide/alkyl lutetium complex (BODDI)Lu2 (CH2 SiMe3 )2 (µ2 -CHSiMe3 )(THF)2 (BODDI=ArNC(Me)CHCOCHC(Me)NAr, Ar=2,6-iPr2 C6 H3 ) (1) was synthesized by a thermolysis methodology through α-H abstraction from a Lu-CH2 SiMe3 group. Complex 1 reacted with equimolar 2,6-iPrC6 H3 NH2 and Ph2 C+O to give the corresponding lutetium bridging imido and oxo complexes (BODDI)Lu2 (CH2 SiMe3 )2 (µ2 -N-2,6-iPr2 C6 H3 )(THF)2 (2) and (BODDI)Lu2 (CH2 SiMe3 )2 (µ2 -O)(THF)2 (3). Treatment of 3 with Ph2 C=O (4 equiv) caused a rare insertion of Lu-µ2 -O bond into theC=O group to afford a diphenylmethyl diolate complex 4. Reaction of 1 with PhN=C=O (2 equiv) led to the migration of SiMe3 to the amido nitrogen atom to give complex (BODDI)Lu2 (CH2 SiMe3 )2 -µ-{PhNC(O)CHC(O)NPh(SiMe3 )-κ(3) N,O,O}(THF) (5). Reaction of 1 withtBuN=C formed an unprecedented product (BODDI)Lu2 (CH2 SiMe3 ){µ2 -[η(2) :η(2) -tBuN=C(=CH2 )SiMe2 CHC=NtBu-κ(1) N]}(tBuN=C)2 (6) through a cascade reaction of N=C bond insertion, sequential cyclometalative γ-(sp(3) )-H activation, C=C bond formation, and rearrangement of the newly formed carbene intermediate. The possible mechanistic pathways between 1, PhN=C=O, and tBuN=C were elucidated by DFT calculations.

Transient receptor potential channel TRPM4 favors oxidized low-density lipoprotein-induced coronary endothelial cell dysfunction via a mechanism involving ferroptosis.

Accelerating the repair of damaged endothelium can effectively inhibit the progression of atherosclerosis (AS). Transient receptor potential channel TRPM4 is a non-selective cation channel activated by internal Ca2+, which is expressed in endothelial cells. This study aimed to reveal the potential role of TRPM4 in AS along with the mechanism. Human coronary artery endothelial cells (HCAECs) induced by ox-LDL was regarded as an in vitro model. The impacts of TRPM4 knockdown on cellular inflammation response, oxidative stress, normal endothelial function and lipid peroxidation were evaluated. Given that ferroptosis promotes AS progression, the effects of TRPM4 on intracellular iron ions and ferroptosis-related proteins was determined. Afterwards, HCAECs were treated with ferroptosis inducer erastin, and the influence of ferroptosis in the cellular model was revealed. TRPM4 was elevated in response to ox-LDL treatment in HCAECs. TRPM4 knockdown reduced the inflammation response, oxidative stress and lipid peroxidation caused by ox-LDL, and maintained the normal function of HCAECs. Erastin treatment destroyed the impacts of TRPM4 knockdown that are beneficial for cells to resist ox-LDL, showing the enhancement of the above adverse factors. Together, this study found that TRPM4 knockdown reduced ox-LDL-induced inflammation, oxidative stress, and dysfunction in HCAECs, possibly via a mechanism involving Fe2+ and ferroptosis-related proteins.

Cerebral Small Vessel Disease Burden in Patients with Transient Global Amnesia and its Relationship with Recurrence.

OBJECTIVE: Cerebral Small Vessel Disease (CSVD) has not been systematically studied in patients with Transient Global Amnesia (TGA). We aimed to investigate the CSVD burden in patients with TGA and its relationship with TGA recurrence. METHODS: We retrospectively examined 69 patients diagnosed with TGA in a single center between January 2015 and November 2023. The overall CSVD burden and single CSVD imaging markers, including enlarged perivascular spaces in the hippocampus (H-EPVS), were measured in each patient and compared with those in 69 age- and sex-matched healthy controls. Multivariate logistic regression was performed to determine independent predictors of recurrence. RESULTS: Of the 69 included patients, 40 (58%) were female, and the median age was 67 years (range 42-83 years). Twenty-one patients (30.4%) showed dot-like hippocampal hyperintensities on diffusion-weighted imaging (DWI). The mean follow-up was 51 months. Sixteen patients (23.2%) experienced TGA recurrence. The burden of overall CSVD, lacunes, WMH, EPVS, and extensive H-EPVS was higher in TGA patients than in controls. TGA patients who experienced recurrence had a heavier overall CSVD burden, lower frequency of hippocampal DWI hyperintensities, and longer follow-up duration than those who had with single episode. In the multivariate analysis, only follow-up duration was an independent predictor of TGA recurrence. CONCLUSION: The overall CSVD burden and extensive H-EPVS burden were higher in patients with TGA than healthy controls. Follow-up duration but not overall CSVD burden may predict TGA recurrence.

High-performance bifacial perovskite solar cells enabled by single-walled carbon nanotubes.

Bifacial perovskite solar cells have shown great promise for increasing power output by capturing light from both sides. However, the suboptimal optical transmittance of back metal electrodes together with the complex fabrication process associated with front transparent conducting oxides have hindered the development of efficient bifacial PSCs. Here, we present a novel approach for bifacial perovskite devices using single-walled carbon nanotubes as both front and back electrodes. single-walled carbon nanotubes offer high transparency, conductivity, and stability, enabling bifacial PSCs with a bifaciality factor of over 98% and a power generation density of over 36%. We also fabricate flexible, all-carbon-electrode-based devices with a high power-per-weight value of 73.75 W g-1 and excellent mechanical durability. Furthermore, we show that our bifacial devices have a much lower material cost than conventional monofacial PSCs. Our work demonstrates the potential of SWCNT electrodes for efficient, stable, and low-cost bifacial perovskite photovoltaics.

How do housing prices affect innovation and entrepreneurship? Evidence from China.

This paper analyzes how housing prices affect innovation and entrepreneurship. We construct a city-level panel dataset including 281 cities between 2009 and 2019 by merging housing price data from China Statistical Yearbook for Regional Economy with innovation and entrepreneurship data from Peking University Open Research Data Platform. Our results suggest that housing prices are positively associated with the vitality of innovation and entrepreneurship (VIE). The results remain consistent with a series of robustness checks. We also find that rising house prices promote VIE through the wealth effect and the siphon effect. Spatial effect analysis further shows that housing prices not only positively affect the VIE of local cities, but also positively affect the VIE of neighboring cities. These findings imply the necessity of curbing the excessive rise of housing prices and decoupling public services and benefits related to homeownership.

Synthesis and Thermoreversible Gelation of Coil-Rod Copolymers with a Dendritic Polyethylene Core and Multiple Helical Poly(γ-benzyl-L-glutamate) Arms.

Coil-rod copolymers with a dendritic polyethylene (DPE) core and multiple helical poly(γ-benzyl-L-glutamate) (PBLG) arms (DPE-(PBLG)n) were prepared by palladium-catalyzed copolymerization in tandem with ring-opening polymerization (ROP). Macroinitiator (DPE-(NH2)11) was firstly prepared by the group transformation of DPE-(OH)11 generated from palladium-catalyzed copolymerization of ethylene and acrylate comonomer. Coil-helical DPE-(PBLG)11 copolymers were prepared by ROP of γ-benzyl-L-glutamate-N-carboxyanhydride (BLG-NCA). These DPE-(PBLG)11 copolymers could form thermoreversible gels in toluene solvent, and the dendritic topology of the DPE core increased the critical gelation concentrations. The self-assembled nanostructure of gels was fully characterized by transmission electron microscopy (TEM), atomic force microscopy (AFM), small-angle X-ray scattering (SAXS), and wide-angle X-ray diffraction (WAXD), and the morphology of the fibrous structure was a twisted flat ribbon through a self-assembled nanoribbon mechanism. The self-assembled fibers formed by DPE-(PBLG45)11 are more heterogeneous and ramified than previously observed fibers formed by PBLG homopolymer and block copolymers.

Tailoring the pore chemistry in porous aromatic frameworks for selective separation of acetylene from ethylene.

The separation of acetylene from ethylene is a crucial process in the petrochemical industry, because even traces of acetylene impurities can poison the catalysts of ethylene polymerization. Herein, we synthesize a new family of 3D porous aromatic frameworks (PAFs), non-functionalized PAF-28, carbene-functionalized PAF-28 (cPAF-28) and imidazolium-functionalized PAF-28 (iPAF-28), via Sonogashira coupling reactions. These PAFs show high porosity and good thermal stability. Both cPAF-28 and iPAF-28 are proved to be good candidates for C2H2 adsorption, demonstrated by C2H2/C2H4 selectivity of 12.2 and 15.4, and C2H2 capacity of 48 cm3 g-1 and 57 cm3 g-1, which are significantly higher than those of non-functionalized PAF-28 (1.8, 37 cm3 g-1). Furthermore, the cPAF-28 and iPAF-28 display good breakthrough performance and remarkable recyclability for the separation of the C2H2/C2H4 gas mixture. In addition, the C2H2/C2H4 adsorption sites are revealed by DFT calculations. This work sheds a new light on gas molecular recognition by tailoring the pore chemistry of PAFs.

[Oncolytic vaccinia virus expressing CD40L (CD40L-VV) inhibits colorectal cancer cell growth and enhances anti-tumor activity of T cells in tumor-bearing mice].

Objective To explore the anti-tumor activity of oncolytic vaccinia virus expressing CD40L (CD40L-VV) against colorectal cancer. Methods The CD40L-VV was obtained by integrating the sequence of CD40L into the skeleton of oncolytic vaccinia virus(VV). The tumor cells were infected with VV and CD40L-VV to verify their oncolytic activity and the expression of CD40L in vitro. After the tumor model of colorectal cancer was treated with VV and CD40L-VV, the tumor growth was monitored, and the phenotype of tumor infiltrating T cells was analyzed by flow cytometry. The anti-tumor activity of recombinant oncolytic VV was also reflected by detecting the production of cytokine and the proliferation activity of tumor infiltrating T cells. Results Microscopic observation and Western blot assay showed that CD40L-VV could effectively infect tumor cells and express CD40L. Cell viability assay showed that VV and CD40L-VV had dose-dependent lytic ability against tumor cells. The results of tumor transplantation in vivo showed that CD40L-VV had stronger ability to inhibiting tumor growth than VV. Flow cytometry showed that tumor infiltrating T cells in the CD40L-VV group had stronger cytokine secretion ability, stronger proliferative activity and more memory cell phenotypes than those in the VV group. Conclusion CD40L-VV can significantly inhibit the growth of colorectal cancer cells and enhance the anti-tumor activity of T cells in vivo.