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Hydrocarbons, when used as the medium for transition metal catalyzed organic reactions and olefin (co‐)polymerization, are ubiquitous. Environmentally friendly water is highly attractive and long‐sought, but is greatly challenging as coordination‐insertion copolymerization reaction medium of olefin and polar monomers. Unfavorable interactions from both water and polar monomer usually lead to either catalyst deactivation or the formation of low‐molecular‐weight polymers. Herein, we develop well‐behaved neutral phosphinophenolato nickel catalysts, which enable aqueous copolymerization of ethylene and diverse polar monomers to produce significantly high‐molecular‐weight linear polar polyolefins (219–549 kDa, 0.13–1.29 mol %) in a single‐component fashion under mild conditions for the first time. These copolymerization reactions occur better in water than in hydrocarbons such as toluene. The dual characteristics of high molecular weight and the incorporation of a small amount of functional group result in improved surface properties while retain the desirable intrinsic properties of high‐density polyethylene (HDPE). [ABSTRACT FROM AUTHOR]

Hydrocarbons, when used as the medium for transition metal catalyzed organic reactions and olefin (co‐)polymerization, are ubiquitous. Environmentally friendly water is highly attractive and long‐sought, but is greatly challenging as coordination‐insertion copolymerization reaction medium of olefin and polar monomers. Unfavorable interactions from both water and polar monomer usually lead to either catalyst deactivation or the formation of low‐molecular‐weight polymers. Herein, we develop well‐behaved neutral phosphinophenolato nickel catalysts, which enable aqueous copolymerization of ethylene and diverse polar monomers to produce significantly high‐molecular‐weight linear polar polyolefins (219–549 kDa, 0.13–1.29 mol %) in a single‐component fashion under mild conditions for the first time. These copolymerization reactions occur better in water than in hydrocarbons such as toluene. The dual characteristics of high molecular weight and the incorporation of a small amount of functional group result in improved surface properties while retain the desirable intrinsic properties of high‐density polyethylene (HDPE). [ABSTRACT FROM AUTHOR]

Electromagnetic ultrasonic detection technology utilizes the electromagnetic coupling method to generate and receive ultrasonic waves without a couplant, which is suitable for rapid detection. However, the detection can be affected by the spatial distribution of the acoustic field and the polarization direction of the shear wave, which can result in suboptimal detection performance. The acoustic field directivity of the shear wave generated by the butterfly coil electromagnetic acoustic transducer was measured using the transmission method. The data indicate that the acoustic pressure amplitude of the shear wave is maximized along the axis of the acoustic field, thereby meeting the requirements of synthetic aperture focusing technique imaging. We used the reflection method to detect the through-hole defects and investigated the effect of shear wave polarization direction. By comparing the experimental data and imaging results, it can be concluded that higher echo amplitudes are obtained when the polarization direction of the shear wave is perpendicular to the axis of the through-hole defects. Based on the explosive reflection model, the frequency domain phase shift migration (PSM) method converts the time-domain signal to the frequency domain for processing and uses a phase-shift factor for layer-by-layer imaging. We used the PSM method to process the experimental data, which not only produced high-resolution images but also had a high computational speed. [ABSTRACT FROM AUTHOR]

Priming of soil organic matter (SOM) decomposition by microorganisms is a key phenomenon of global carbon (C) cycling. Soil pH is a main factor defining priming effects (PEs) because it (i) controls microbial community composition and activities, including enzyme activities, (ii) defines SOM stabilization and destabilization mechanisms, and (iii) regulates intensities of many biogeochemical processes. In this critical review, we focus on prerequisites and mechanisms of PE depending on pH and assess the global change consequences for PE. The highest PEs were common in soils with pH between 5.5 and 7.5, whereas low molecular weight organic compounds triggered PE mainly in slightly acidic soils. Positive PEs up to 20 times of SOM decomposition before C input were common at pH around 6.5. Negative PEs were common at soil pH below 4.5 or above 7 reflecting a suboptimal environment for microorganisms and specific SOM stabilization mechanisms at low and high pH. Short‐term soil acidification (in rhizosphere, after fertilizer application) affects PE by: mineral‐SOM complexation, SOM oxidation by iron reduction, enzymatic depolymerization, and pH‐dependent changes in nutrient availability. Biological processes of microbial metabolism shift over the short‐term, whereas long‐term microbial community adaptations to slow acidification are common. The nitrogen fertilization induced soil acidification and land use intensification strongly decrease pH and thus boost the PE. Concluding, soil pH is one of the strongest but up to now disregarded factors of PE, defining SOM decomposition through short‐term metabolic adaptation of microbial groups and long‐term shift of microbial communities. [ABSTRACT FROM AUTHOR]

The 1605 M7½ Earthquake is the only earthquake in the history of China that has caused large-scale land subsidence into the sea, with the total area of land subsidence exceeding 100 km2. The disaster has led to the sinking of 72 villages. There is still no clear understanding of the source seismogenic fault of this earthquake. In this work, we conducted a detailed study of the middle segment of the Maniao-Puqian fault (MPF), which is the epicenter area, through geomorphological survey, data collection, shallow seismic exploration, cross-section drilling, and chronological dating. The results showed that the middle segment of the MPF zone is composed of three nearly parallel normal faults with a dextral strike-slip: "Macun-Luodou fault (F2-1), Haixiu-Dongyuan fault (F2-2), and Changliu-Zhuxihe fault (F2-3)". And F2-2 is composed of two secondary faults, namely F2-2′ and F2-2″, with a flower-shaped structure buried under the ground. It is distributed nearly east-west, dipping to the north and has experienced at least five stages of activities since the Miocene. The vertical activity rates of F2-2′ and F2-2″ are ∼2.32 and ∼2.5 mm/a, since the Holocene, respectively. There were eight cycles of transgression and regression since the Miocene. The fault activity resulted in the thickening of the Holocene strata with a slight dip to the south, on the hanging wall, showing V-shaped characteristics. The MPF is likely the source seismogenic fault of the M7½ earthquake that hit Qiongshan in 1605. [ABSTRACT FROM AUTHOR]

Rhizosphere engineering is the targeted manipulation of plants, soil, microorganisms, and agricultural management to shift pools and processes in the rhizosphere for specific aims. Physical, chemical, and biological approaches as well as farming practices allow engineering of the rhizosphere to increase carbon (C) sequestration. Rhizosphere engineering approaches focus on the accumulation and stabilization of C in the soil either directly or indirectly through: (i) raising root-derived C inputs; (ii) increasing the production of microbial biomass and necromass; and (iii) enhancing C stabilization in the soil. Rhizosphere engineering is crucial to manage rhizodeposition, microbial activities, and plant–soil–microbial interactions, and thus soil C sequestration under global change and human impacts. The rhizosphere is the central hotspot of water and nutrient uptake by plants, rhizodeposition, microbial activities, and plant-soil-microbial interactions. The plasticity of plants offers possibilities to engineer the rhizosphere to mitigate climate change. We define rhizosphere engineering as targeted manipulation of plants, soil, microorganisms, and management to shift rhizosphere processes for specific aims [e.g., carbon (C) sequestration]. The rhizosphere components can be engineered by agronomic, physical, chemical, biological, and genomic approaches. These approaches increase plant productivity with a special focus on C inputs belowground, increase microbial necromass production, protect organic compounds and necromass by aggregation, and decrease C losses. Finally, we outline multifunctional options for rhizosphere engineering: how to boost C sequestration, increase soil health, and mitigate global change effects. [ABSTRACT FROM AUTHOR]

Five new alkylaluminum complexes with different pyridinyl-substituted imines or cyclohexyl-substituted imines were synthesized and characterized successfully. The aluminum complex [FlCHNCH(CH3)Py]AlMe2(Py = 2-pyridyl) (1) was obtained by reacting 9-[2-pyridyl-CH(CH3)-N＝CH]Fl (Fl = fluorenyl) (L1) and equimolar AlMe3. The reactions of 9-(2-pyridyl-N＝CH)Fl (L2) and 9-[2-N(CH3)2-cyclohexyl-N＝CH]Fl (L3) with equimolar AlMe3 or AlEt3 afforded other alkylaluminum complexes [FlCHNPy]AlMe2(Py = 2-pyridyl) (2), [FlCHNPy]AlEt2 (Py = 2-pyridyl) (3), [FlCHNCyN(CH3)2]AlMe2 (Cy = 2-cyclohexyl) (4) and [FlCHNCyN(CH3)2]AlEt2 (Cy = 2-cyclohexyl) (5). All these complexes (1–5) were characterized using NMR spectroscopy, elemental analysis, and X-ray crystal structure analysis. The catalytic properties of these new alkylaluminum complexes for the hydrophosphonylation of aldimines were examined. Complex 5 showed the best catalytic performance under mild reaction conditions with a low catalyst loading (1 mol%), and 20 different substituents of aldimines were isolated with more than 90% yields. [ABSTRACT FROM AUTHOR]

Hydnum is a well-characterized genus in the family Hydnaceae of Cantharellales and is characterized by spinose hymenophores. In this study, an ITS phylogenetic overview and a multilocus (ITS-nrLSU-tef1) phylogenetic tree of Hydnum were carried out. On the basis of morphological characteristics and phylogenetic results, seven species from China were confirmed, described, illustrated, and compared with similar species, including three new species, i.e., H. longipes, H. microcarpum, and H. sinorepandum, and four known species, i.e., H. cremeoalbum, H. melitosarxm, H. orientalbidum, and H. pinicola were recorded for the first time in China. A key to the species of Hydnum in China was provided. [ABSTRACT FROM AUTHOR]

This article, published in the journal Global Change Biology, discusses the role of energy in microbial processes in soil. The authors address questions raised by another study and highlight the importance of energy for microorganisms in soil. They emphasize that microorganisms primarily use organic carbon as an energy source rather than for biomass production. The article also discusses the concept of microbial energy use efficiency (EUE) and how it can be assessed using the enthalpy of organic compounds. The authors conclude that understanding the energy content of substrates can help calculate the enthalpy changes in soil systems. [Extracted from the article]

Qualitative ratings are increasingly used to assess animal welfare. We investigated the associations between daily caretakers' ratings of individuals' behavioral style, behavior during free time, participation during training sessions, and environmental variables in captive Yangtze finless porpoises, East-Asian finless porpoises, and bottlenose dolphins. Associations between caretakers' ratings and behavior were found, including social swimming, fast swimming, play, interaction with humans, and agonistic and socio-sexual interactions. Ratings were also associated with participation during training sessions and food intake. Social separation, transport to a new pool, high visitors' density, and holding of a sick conspecific were associated with ratings indicating a deteriorated human–animal relationship, a lower interest/fear of the environment, and/or a higher social cohesion depending on the group. Through principal component analyses, new variables that represented both caretakers' ratings and behavior and that could be used for an easier interpretation of the data for welfare monitoring within each group were extracted. Caretaker ratings and behavior should be used as a complement to previously validated indicators to detect changes in welfare state and understand the potential causes of these changes. [ABSTRACT FROM AUTHOR]

Background and Aims: Hepatic ischaemia/reperfusion injury (HIRI) is a pathophysiological process that occurs during the liver resection and transplantation. Reportedly, peroxisome proliferator‐activated receptor β/δ (PPARβ/δ) can ameliorate kidney and myocardial ischaemia/reperfusion injury. However, the effect of PPARβ/δ in HIRI remains unclear. Methods: Mouse hepatic ischaemia/reperfusion (I/R) models were constructed for in vivo study. Primary hepatocytes and Kupffer cells (KCs) isolated from mice and cell anoxia/reoxygenation (A/R) injury model were constructed for in vitro study. Liver injury and inflammation were investigated. Small molecular compounds (GW0742 and GSK0660) and adenoviruses were used to interfere with PPARβ/δ. Results: We found that PPARβ/δ expression was increased in the I/R and A/R models. Overexpression of PPARβ/δ in hepatocytes alleviated A/R‐induced cell apoptosis, while knockdown of PPARβ/δ in hepatocytes aggravated A/R injury. Activation of PPARβ/δ by GW0742 protected against I/R‐induced liver damage, inflammation and cell death, whereas inhibition of PPARβ/δ by GSK0660 had the opposite effects. Consistent results were obtained in mouse I/R models through the tail vein injection of adenovirus‐mediated PPARβ/δ overexpression or knockdown vectors. Furthermore, knockdown and overexpression of PPARβ/δ in KCs aggravated and ameliorated A/R‐induced hepatocyte injury, respectively. Gene ontology and gene set enrichment analysis showed that PPARβ/δ deletion was significantly enriched in the NF–κB pathway. PPARβ/δ inhibited the expression of p‐IKBα and p‐P65 and decreased NF–κB activity. Conclusions: PPARβ/δ exerts anti‐inflammatory and anti‐apoptotic effects on HIRI by inhibiting the NF–κB pathway, and hepatocytes and KCs may play a synergistic role in this phenomenon. Thus, PPARβ/δ is a potential therapeutic target for HIRI. [ABSTRACT FROM AUTHOR]

Carbon use efficiency (CUE) is being intensively applied to quantify carbon (C) cycling processes from microbial cell to global scales. Energy use efficiency (EUE) is at least as important as the CUE because (i) microorganisms use organic C mainly as an energy source and not as elemental C per se, and (ii) microbial growth and maintenance are limited by energy, but not by C as a structural element. We conceptualize and review the importance of EUE by soil microorganisms and focus on (i) the energy content in organic compounds depending on the nominal oxidation state of carbon (NOSC), (ii) approaches to assess EUE, (iii) similarities and differences between CUE and EUE, and (iv) discuss mechanisms responsible for lower EUE compared to CUE. The energy content per C atom (enthalpy of combustion, the total energy stored in a compound) in organic compounds is very closely (R2 = 0.98) positively related to NOSC and increases by 108 kJ mol−1 C per one NOSC unit. For the first time we assessed the NOSC of microbial biomass in soil (−0.52) and calculated the corresponding energy content of −510 kJ mol−1 C. We linked CUE and EUE considering the NOSC of microbial biomass and element compositions of substrates utilized by microorganisms. The mean microbial EUE (0.32–0.35) is 18% lower than CUE (0.41) using glucose as a substrate. This definitely indicates that microbial growth is limited by energy relative to C. Based on the comparison of a broad range of processes of C and energy utilization for cell growth and maintenance, as well as database of experimental CUE from various compounds, we clearly explained five mechanisms and main factors why EUE is lower than CUE. The two main mechanisms behind lower EUE versus CUE are: (i) microbial recycling: C can be microbially recycled, whereas energy is always utilized only once, and (ii) chemical reduction of organic and inorganic compounds: Energy is used for reduction, which is ongoing without C utilization. [ABSTRACT FROM AUTHOR]

Background: Evidence has emerged that altered ventricular electrocardiogram profiles are associated with dementia, but the neuropathological mechanisms underlying their associations are poorly understood. Objective: To investigate the interrelationships of ventricular electrocardiogram profiles with dementia and plasma Alzheimer's disease (AD) biomarkers among older adults. Methods: This population-based cross-sectional study included 5,153 participants (age ≥65 years; 57.3% women) living in rural communities in China; of these, 1,281 had data on plasma amyloid-β (Aβ)40, Aβ42, total-tau, and neurofilament light chain (NfL) protein. The QT, QTc, JT, JTc, QRS intervals, and QRS axis were derived from the 10-second electrocardiogram recording. The DSM-IV criteria were followed for clinical diagnosis of dementia, the NIA-AA criteria for AD, and the NINDS-AIREN criteria for vascular dementia (VaD). Data were analyzed using general linear models, multinomial logistic models, and restricted cubic splines. Results: Of the 5,153 participants, 299 (5.8%) were diagnosed with dementia, including 194 with AD and 94 with VaD. Prolonged QT, QTc, JT, and JTc intervals were significantly associated with all-cause dementia, AD, and VaD (p < 0.05). Left QRS axis deviation was significantly associated with all-cause dementia and VaD (p < 0.01). In the subsample of plasma biomarkers (n = 1,281), prolonged QT, JT, and JTc intervals were significantly associated with a lower Aβ42/Aβ40 ratio and higher plasma NfL concentrations (p < 0.05). Conclusion: Alterations in ventricular repolarization and depolarization are independently associated with all-cause dementia, AD, VaD, and AD plasma biomarkers in older adults (age ≥65 years). Ventricular electrocardiogram parameters may be valuable clinical markers for dementia and the underlying AD pathologies and neurodegeneration. [ABSTRACT FROM AUTHOR]

The degradation of plastics has attracted much attention from the global community. Polyethylenes (PEs), as the most abundant synthetic plastics, are most frequently studied. PE is non-degradable and non-polar because of the sole presence of the pure hydrocarbon components. Concurrent incorporation of both in-chain cleavable and functional groups into the PE chain is an effective pathway to overcome the non-degradable and non-polar issue; however, the method for achieving this pathway remains elusive. Here, we report a strictly non-alternating (>99%) terpolymerization of ethylene with CO and fundamental polar monomers via a coordination–insertion mechanism using late transition metal catalysts, which effectively prevents the formation of undesired chelates originating from both co-monomers under a low CO concentration. High-molecular-weight linear PEs with both in-chain isolated keto (>99%) and main-chain functional groups are prepared. The incorporation of key low-content isolated keto groups makes PEs photodegradable while retaining their desirable bulk material properties, and the introduction of polar functional groups considerably improves their surface properties. [ABSTRACT FROM AUTHOR]

Children with ADHD are reported to accompany by various degrees of recognition memory cognitive deficits. We aimed to investigate age-related changes of the amplitude in event-related potential recordings on recognition memory in Chinese children with ADHD and to provide theoretical basis of neuro-electrophysiology for the cognition development of children ERP and behavioral data of 6- to -10-year-old children with ADHD (n = 94) and typically developing controls (TD, n = 96) were collected while the children performed a classical visual study-test paradigm task. Children with ADHD have defects in pictures recognition and showed a significantly smaller P2 component than that of TD children. The development of P2 and P3 component were different between the two groups. Moreover, the TD children showed the frontal old/new effect (N2) taken as a correlate of familiarity at 6 years old, and a parietal old/new effect (P3) taken as a correlate of recollection at 9 years old, while children with ADHD showed a parietal old/new effect (P3) only at 6 years old. Our study provided the novel evidence that recognition memory follow different developmental trajectories at the age of 6–10 between TD and ADHD. [ABSTRACT FROM AUTHOR]

• WWC1 rs17070145 was marginally associated with AD and VaD in older adults. • WWC1 exonic SNPs rs3822660 and rs3822659 are in strong LD with rs17070145. • The strong LD may explain the association of WWC1 rs17070145 C allele with AD. • Stroke may partly explain the association of rs17070145 CC genotype with VaD. We sought to examine the associations of common WWC1 variants with Alzheimer's disease (AD) and vascular dementia (VaD) among rural-dwelling older adults in China. This population-based study used data from the baseline assessments (March –September 2018) of MIND-China. AD and VaD were diagnosed following the international criteria. Of the 5455 participants (age≥60 years, 57.27% women), 182 were diagnosed with AD and 88 with VaD. Logistic regression analysis suggested that WWC1 rs17070145 C allele (vs. T) was associated with multivariable-adjusted odds ratio of 1.23 (95% confidence interval 0.96–1.58) for AD, and that CC genotype (vs. TT) was associated with multivariable-adjusted odds ratio of 2.19(1.10–4.39) for VaD, but the association with VaD became non-significant when further adjusting for stroke history. Furthermore, exonic SNPs rs3822660 and rs3822659 were in strong linkage disequilibrium (LD) with rs17070145 (D' = 0.88). These results suggest that the strong LD between rs17070145 and 2 exonic SNPs may explain the association of WWC1 rs17070145 C allele with AD and that stroke may partly explain the association of WWC1 rs17070145 CC genotype with VaD. [ABSTRACT FROM AUTHOR]

Simple Summary: Glioblastoma is the most prevalent cerebral cancer in adults without proven therapy. Chimeric antigen receptor T cell treatment has demonstrated good clinical success in hematologic cancers. The application of chimeric antigen receptor T cell therapy to solid tumors, such as glioblastoma, is currently the subject of scientific investigation. The creation of chimeric antigen receptor T cells and its iterations are briefly described in this article. Specifically, this study addresses the obstacles and hurdles faced and glioblastoma targets studied in recent years. This review provides the reader with a comprehensive understanding of the current state of chimeric antigen receptor T cell therapy for glioblastoma and a clear understanding of each therapeutic target. Glioblastoma (GBM) is an aggressive primary brain tumor with a poor prognosis following conventional therapeutic interventions. Moreover, the blood–brain barrier (BBB) severely impedes the permeation of chemotherapy drugs, thereby reducing their efficacy. Consequently, it is essential to develop novel GBM treatment methods. A novel kind of pericyte immunotherapy known as chimeric antigen receptor T (CAR-T) cell treatment uses CAR-T cells to target and destroy tumor cells without the aid of the antigen with great specificity and in a manner that is not major histocompatibility complex (MHC)-restricted. It has emerged as one of the most promising therapy techniques with positive clinical outcomes in hematological cancers, particularly leukemia. Due to its efficacy in hematologic cancers, CAR-T cell therapy could potentially treat solid tumors, including GBM. On the other hand, CAR-T cell treatment has not been as therapeutically effective in treating GBM as it has in treating other hematologic malignancies. CAR-T cell treatments for GBM have several challenges. This paper reviewed the use of CAR-T cell therapy in hematologic tumors and the selection of targets, difficulties, and challenges in GBM. [ABSTRACT FROM AUTHOR]

Background: Emerging evidence has linked electrocardiographic parameters with serum adhesion molecules and cognition; however, their interrelationship has not been explored. Objective: We sought to investigate the associations of ventricular depolarization and repolarization intervals with serum adhesion molecules and cognitive function among rural-dwelling older adults. Methods: This population-based study engaged 4,886 dementia-free participants (age ≥60 years, 56.2% women) in the baseline examination (March-September 2018) of MIND-China. Of these, serum intercellular and vascular adhesion molecules (ICAM-1 and VCAM-1) were measured in 1591 persons. We used a neuropsychological test battery to assess cognitive function. Resting heart rate, QT, JT intervals, and QRS duration were assessed with electrocardiogram. Data were analyzed using general linear models adjusting for multiple confounders. Results: Longer JT interval was significantly associated with lower z-scores of global cognition (multivariable-adjusted β= –0.035; 95% confidence interval = –0.055, –0.015), verbal fluency (–0.035; –0.063, –0.007), attention (–0.037; –0.065, –0.010), and executive function (–0.044; –0.072, –0.015), but not with memory function (–0.023; –0.054, 0.009). There were similar association patterns of QT interval with cognitive functions. In the serum biomarker subsample, longer JT and QT intervals remained significantly associated with poorer executive function and higher serum adhesion molecules. We detected statistical interactions of JT interval with adhesion molecules (pinteraction <0.05), such that longer JT interval was significantly associated with a lower executive function z-score only among individuals with higher serum ICAM-1 and VCAM-1. Conclusion: Longer ventricular depolarization and repolarization intervals are associated with worse cognitive function in older adults and vascular endothelial dysfunction may play a part in the associations. [ABSTRACT FROM AUTHOR]

Polar-functionalized polyolefins are high-value materials with improved properties. However, their feedstocks generally come from non-renewable fossil products; thus, it requires the development of renewable bio-based monomers to produce functionalized polyolefins. In this contribution, via the Pd-catalyzed telomerization of 1,3-butadiene and three types of bio-based alcohols (furfuryl alcohol, tetrahydrofurfuryl alcohol, and solketal), 2,7-octadienyl ether monomers including OC8-FUR, OC8-THF, and OC8-SOL were synthesized and characterized, respectively. The copolymerization of these monomers with ethylene catalyzed by phosphine–sulfonate palladium catalysts was further investigated. Microstructures of the resultant copolymers were analyzed by NMR and ATR-IR spectroscopy, revealing linear structures with incorporations of difunctionalized side chains bearing both allyl ether units and polar cyclic groups. Mechanical property studies exhibited better strain-at-break of these copolymers compared to the non-polar polyethylene, among which the copolymer E-FUR with the incorporation of 0.3 mol% displayed the highest strain-at-break and stress-at-break values of 940% and 35.9 MPa, respectively. [ABSTRACT FROM AUTHOR]

In this article presents a trajectory planning approach toward safe and smooth robot motion in dynamic environments. We develop a hierarchical planning framework with a global planner generating the shortest path between the robot and the navigation target. Specially, a virtual target (VT) is set to run on the global path with a designed velocity. At the local level, the robot chases the VT and tracks the global path when traveling through the dynamic environment. We employ the model predictive control (MPC) framework for the local path generation. In particular, the prediction horizon of the MPC is adaptively changed concerning the distance between the robot and the VT. It implicitly reflects the crowdedness of the environment, which helps reduce the environmental uncertainty. Besides, we develop an event-triggered mechanism that executes the local plan aperiodically to release the computational burden. Based on the local chasing and tracking performance, we develop a global path replanning scheme in response to the untraversable area emerging in the dense environment. The developed framework is validated through extensive experiments in dynamic environments, demonstrating that the robot can reach the target faster and showcase a safer and smoother trajectory in the navigation. [ABSTRACT FROM AUTHOR]

At present, the frontier-based exploration has been one of the mainstream methods in autonomous robot exploration. Among the frontier-based algorithms, the method of searching frontiers based on rapidly exploring random trees consumes less computing resources with higher efficiency and performs well in full-perceptual scenarios. However, in the partially perceptual cases, namely when the environmental structure is beyond the perception range of robot sensors, the robot often lingers in a restricted area, and the exploration efficiency is reduced. In this article, we propose a decision-making method for robot exploration by integrating the estimated path information gain and the frontier information. The proposed method includes the topological structure information of the environment on the path to the candidate frontier in the frontier selection process, guiding the robot to select a frontier with rich environmental information to reduce perceptual uncertainty. Experiments are carried out in different environments with the state-of-the-art RRT-exploration method as a reference. Experimental results show that with the proposed strategy, the efficiency of robot exploration has been improved obviously. [ABSTRACT FROM AUTHOR]

• This study was the first to link the causal relationship among uric acid, T2DM, and ischemic stroke with its subtypes using Mendelian randomization. • The causal relationship between uric acid and ischemic stroke, especially LAS and SVS, was elucidated by Two-sample Mendelian randomization. • Two-step mediation analysis revealing that the impact of uric acid on LAS and SVS risk was partly mediated through T2DM. This study conducts a systematic investigation into the causal relationships between plasma uric acid levels and subtypes of ischemic stroke (IS), as well as the extent to which Type 2 diabetes mellitus (T2DM) mediates this relationship. There is a known association between Uric acid and IS but whether they have a causal relationship remains unclear. This study aims to determine whether a genetic predisposition to uric acid is causally linked to IS, including three subtypes, and to determine the mediating role of T2DM. Bidirectional Mendelian randomization (MR) analyses was initially used to explore the causal relationship between uric acid and three subtypes of IS. Two-step MR methods were then used to investigate the role of T2DM in mediating the effect of uric acid and IS with its subtypes. A primary analysis showed uric acid had a markedly causal association with IS (IVW, OR 1.23; 95 % CI, 1.13 − 1.34; p = 6.39 × 10-9), and two subtypes of IS, Large-vessel atherosclerotic stroke LAS (IVW, OR 1.25; 95 % CI, 1.03 − 1.53; p = 0.026) and small vessel stroke (SVS) (IVW, OR 1.20; 95 % CI, 1.00 − 1.43; p = 0.049), but not with cardioembolic stroke (CES)(IVW, OR 1.00; 95 % CI, 0.87 − 1.15; p = 0.993). Two-step MR results showed that T2DM mediated the association between uric acid and LAS and SVS, accounting for 13.85 % (p = 0.025) and 13.57 % (p = 0.028), respectively. The study suggests that genetic predisposition to uric acid is linked to a greater risk of IS, especially LAS and SVS. T2DM might mediate a significant proportion of the associations between uric acid and LAS as well as SVS. [ABSTRACT FROM AUTHOR]

In environmental monitoring programs, mobile robots have been widely deployed for remote sensing, with the end objective of monitoring and mapping out environmental fields. Complex characteristics and correlations in natural phenomena make it challenging to establish a reliable framework for mobile sensing and field mapping. Furthermore, constraints of onboard resources will limit the ability of mobile robots to cover a large area. This article focuses on the active sensing problem in environmental field mapping and particularly exploits the use of intrinsic interactions among multivariate spatiotemporal data. A novel deep neural network of a hybrid CNN-RNN model is employed to learn the monitored multivariate spatiotemporal field. Specifically, a set of attention mechanisms is designed and embedded in the network, which is able to adaptively capture parameterwise dependencies among the monitored heterogeneous parameters and spatial correlations in geolocations of a surveyed field. The weights of inferred attention facilitate explicit interpretation of the driving parameters and geolocations. Some subregions of interest in the surveyed field are specified by their spatial attention distribution and are actively sensed by following the proposed coverage path planner. Experiments are carried out using a real-world dataset with multisource environmental imagery from a remote sensing program. Experimental results are obtained, which demonstrate the superior mapping performance of the proposed systematical methodology compared to baseline methods. Furthermore, the proposed model is able to quantitatively reveal the driving monitored parameters and geolocations in a regression process. Note to Practitioners—This article was motivated by the need for a practical and systematic approach for reconstruction and planning to execute robotic active sensing (AS) in environmental field mapping. Field robotic applications are not maneuverable in comparison with indoor scenarios due to severe conflict between the need for long execution endurance in the field and the very limited onboard resources. Traditional AS planners normally use statistical model-based informative metrics, which may lead to model misspecification in real-world phenomena. The developed framework in this article yields a novel attention-driven metric to guide AS and mapping. It relies on an attention-based hybrid neural network that reveals the driving variables in terms of the heterogeneities and complexities in a natural environment. The high-priority regions are maximized in a coverage path depending on the inferred spatial attention distribution while maintaining the travel cost of the sensing robots within an available energy budget. Experiments using a remote sensing dataset validate the reliable performance of the proposed framework, in environmental field mapping. [ABSTRACT FROM AUTHOR]

Research in the areas of inflammation and mitochondrial stress in ischemic stroke is rapidly expanding, but a comprehensive overview that integrates bibliometric trends with an in-depth review of molecular mechanisms is lacking. To map the evolving landscape of research using bibliometric analysis and to detail the molecular mechanisms that underpin these trends, emphasizing their implications in ischemic stroke. We conducted a bibliometric analysis to identify key trends, top contributors, and focal research themes. In addition, we review recent research advances in mitochondrial stress and inflammation in ischemic stroke to gain a detailed understanding of the pathophysiological processes involved. Our integrative approach not only highlights the growing research interest and collaborations but also provides a detailed exploration of the molecular mechanisms that are central to the pathology of ischemic stroke. This synthesis offers valuable insights for researchers and paves the way for targeted therapeutic interventions. [ABSTRACT FROM AUTHOR]

Alternate wetting-drying (AWD) in rice cultivation controls soil redox conditions and consequently nutrient solubility. Under low redox potential, ferric iron reduction leads to bound phosphate (Fe(III)–P) dissolution, but lack of oxygen retards organic phosphorus (P org) mineralization. Microorganisms accelerate P org mineralization as the redox potential increases during drying, but it is not known which P source will be preferentially taken up by microorganisms and plants. Using double 32/33P labeling, we traced for the first time the P released from inorganic (32P) and organic (33P) sources into microbial biomass P (MBP), phospholipids, and plants under continuous flooding (CF) and AWD. The CF rapidly induced reducing conditions that increased Fe–P dissolution and thus P availability. The AWD had no preference for 32P and 33P incorporation into plants. However, the ratios of 32P in roots to 32P in MBP or to 32P in phospholipids in rooted soil were 4–9 times higher than the respective ratios of 33P. Moreover, the ratios of 33P in roots to 33P in MBP or to 33P in phospholipids were always <0.6. Thus, plants and microorganisms were more competitive for P from Fe–P and from P org , respectively. The AWD increased 32P and 33P incorporation into phospholipids in rooted soil by 53–56% as compared to CF. Also, the ratio of 32P in phospholipids to 32P in MBP was 1.4–2.2 times higher under AWD than under CF. Thus, AWD stimulated microorganisms to allocate more P for cell membrane synthesis as compared to CF. Plants were similarly effective to take up P from inorganic and organic sources. Increased root biomass stimulated arbuscular mycorrhizal symbiosis (represented by 16:1ω5c) and thus 33P recovery in roots under AWD. In turn, the acceleration of microbial P turnover and the microbe-specific preference for P org highlight the importance of arbuscular mycorrhiza for plant P uptake under fluctuating water conditions. [Display omitted] • Continuous flooding increased reductive dissolution of Fe–P and thus P availability. • Microbes allocated more P for cell membrane synthesis under alternate wetting-drying. • Microorganisms in a maintenance state allocated more P for cell compound synthesis. • Rice plants were similarly effective to take up P from inorganic and organic sources. [ABSTRACT FROM AUTHOR]

Security in rice production requires solving challenges of water scarcity and phosphorus (P) limitations. Reductive dissolution of ferric (III) iron bound phosphate (Fe–P) and organic P (P org) mineralization are two understudied P sources for rice plants and microorganisms. Using the new water-saving alternate wetting-drying irrigation should increase P org mineralization but decrease the Fe–P dissolution and thereby shift the plant and microbial preferences for P sources. Rice biomass increased two-fold under alternate wetting-drying compared to continuous flooding, but the P use efficiency of plants was independent of water regimes. Plants were more competitive for P from Fe–P by Fe(III) reduction, whereas microorganisms preferred straw-derived P (enzymatic hydrolyzation). The high contribution (∼20 %) of P from straw to the P nutrition of rice plants and microorganisms raises the significance of P org mineralization, e.g. from organic fertilizers. This makes the application of organic P fertilizers highly beneficial to increase rice productivity. Plants took up 62 % more soil-derived P under alternate wetting-drying than under continuous flooding. Accordingly, alternate wetting-drying is a more efficient management to increase the use of soil legacy P and reduce the use of mineral fertilizers compared to continuous flooding. • Continuous flooding increased P availability in soil solution. • Alternate drying-wetting was beneficial for increased use of soil-derived P sources. • Phosphorus uptake efficiency of plants was independent of water regimes. • Microorganisms preferred straw-derived P through enzymatic hydrolyzation over Fe–P. • Rice plants outcompeted microorganisms for P from Fe–P by Fe(III) reduction. [ABSTRACT FROM AUTHOR]

Phytoremediation is an environmentally friendly, economical, and sustainable technique for restoring farmland. It can remove heavy metals and organic pollutants from the soil through the implementation of hyperaccumulator plants. In recent years, it has garnered significant interest from academic and industrial sectors. This article screened 368 research papers from the Web of Science core collection database related to farmland phytoremediation and conducted a bibliometric analysis of the domain based on CiteSpace. The paper intuitively demonstrates the most influential countries, the most productive institutions, the most contributing groups of authors, and the primary sources of farmland phytoremediation research domain. The findings additionally indicate that the research hotspots include: (1) mechanisms and principles of phytoremediation, (2) the improvement of restoration efficiency, (3) the economic, ecological, and sustainable development of phytoremediation. The exploration of plants with potential to accumulate heavy metals and produce large amounts of biomass is the research frontier within the field of farmland phytoremediation. Additionally, this bibliometric analysis can help scholars willing to work in this research field by concisely understanding the overall research field and frontiers. With the continuous improvement of phytoremediation and its combination with other remediation technologies, the future of farmland remediation will have a promising prospect. • Papers of farmland phytoremediation in the past three decades were comprehensively and systematically bibliometric analyzed. • Internal connection of farmland phytoremediation was elaborated from various aspects. • Research hotspots and frontiers of farmland phytoremediation were clarified through keyword cluster analysis. [ABSTRACT FROM AUTHOR]

Background: The objective of the study is to determine the safety and efficiency of the modified laparoscopic percutaneous extraperitoneal closure (LPEC) to treat pediatric patients with inguinal hernia or hydrocele. Methods: From January 2014 to July 2018, the patients with inguinal hernia or hydrocele who were operated on using modified LPEC were included. We modified LPEC with a sledge-shaped needle and reinforcement flag. By means of medial umbilical fold, the reinforcement surgery should be performed on the patients with huge internal rings (diameter >1.5 cm). Operative time, complication rate, incidence of reinforcement, and contralateral patent processus vaginalis were described between inguinal hernia and hydrocele. Results: In this study, 764 patients with inguinal hernia and 435 patients with hydrocele were successfully performed by the modified LPEC. The 383 (50.1%) patients with inguinal hernia and 266 (61.1%) patients with hydrocele were identified with a contralateral patency of internal ring and underwent simultaneous prophylactic surgery. During surgical procedures, the medial umbilical fold reinforcement (inguinal hernia/hydrocele = 50/1) was performed on 51 patients. Hernia recurrence occurred in 2 cases. All patients had a good cosmetic appearance without additional dissection. Conclusion: Modified LPEC using a sledge-shaped needle and applying the medial umbilical fold reinforcement is a safe and effective surgical procedure. [ABSTRACT FROM AUTHOR]

What effects the stand age has on the soil microbial structure and composition remains unclear. The topsoil (0–20 cm) of 3- (YF), 12- (MAF), and 38-year-old (MF) Chinese fir plantations were selected as research objects. We found that the phospholipid fatty acid (PLFA) concentration and OTUs of bacteria and fungi exhibited an uptrend as the stand age increased. Among dominant bacterial and fungal phyla, the relative abundance of Actinobacteria in YF was significantly higher than that in MF and MAF and the relative abundance of Basidiomycota in MF was significantly higher than that in MAF and YF. Interestingly, the relative abundance of three predominant fungal phyla Ascomycota, Basidiomycota, and Zygomycota in MAF were lower than those in MF and YF. The significant difference in the relative abundance of some bacterial phyla (e.g., Ignavibacteriae, Latescibacteria, Nitrospirae, and Tectomicrobia) was also found with stand age, and organic matter, pH, available P, available N, and available K were the main factors for the variances in the biomass and structure of soil microbial communities. These findings showed that considering the shift in the structure and composition of microbial communities might improve our understanding of soil fertility maintenance and sustainable management of these plantations. [ABSTRACT FROM AUTHOR]

Polymers are used widely in various kinds of drilling fluid to maintain the proper rheological properties. However, most of them are not available for high-temperature or salt solutions due to poor temperature and salt resistance. To ameliorate the temperature and salt resistance of polymer used in the solid-free water-based drilling fluid, a novel polymer with a kind of "Mesh-Lock" reinforced network cross structure, named PLY-F [main monomer acrylic acid (AA), acrylamide (AM), functional monomers 2-acrylamide-2-methylpropanesulfonic acid (AMPS) N-vinylpyrrolidone (NVP) and C16DMAAC] were prepared through free radical polymerization of an aqueous solution of organic cross-linking agent pentaerythritol triallyl ether (PTE) as a cross-linking system, Potassium persulfate (KPS) and sodium bisulfite as the initiator for the first time. The surface morphology, crosslinking architecture and temperature and salt resistance of the PLY-F were fully characterized with several means including SEM, FT-IR, 13CNMR, dynamic rheology, and long-term thermal stability. The SEM observation indicated that the PLY-F exhibits a regular "Mesh-Lock" reinforced network cross structure. FT-IR, 13CNMR analysis indicated that the characteristic functional groups of each monomer such as AM, AA, AMPS and NVP were all together in the polymer. The results show that the apparent viscosity retention rate of the PLY-F in the potassium formate solution (with a density of 1.3 g/cm3) was more than 80% after heat rolling for 72 h at 200 °C and the plastic viscosity retention rate reached 90.3%. Moreover, the salt resistance of the polymer can reach the density of 1.4 g/cm3 (potassium formate solution) under 200 °C and the temperature resistance can reach 220 °C under the density of 1.3 g/cm3 (potassium formate solution). Besides, the PLY-F still has good rheological properties in other saturated solutions (NaCl, HCOONa) under 210 °C. [ABSTRACT FROM AUTHOR]

Via a short 3-step pathway, neutral phenoxy-imine nickel catalysts are synthesized which promote ethylene polymerization to afford linear UHMWPE in a living manner. [Display omitted] • Low-cost and facile three-step synthetic pathway for neutral nickel catalysts. • Capability of catalyzing ethylene polymerization in a living manner. • Production of ultrahigh molecular weight polyethylene. • Enabling copolymerization of ethylene and polar monomer. It is of great importance and is highly desired in the olefin polymerization catalysis that a simple catalyst derived from cheap starting materials and short synthetic pathways exhibits superior catalytic property towards a polymerization reaction. In this contribution, starting from commercially available and cheap materials, by using a short and simple three-step reaction route we report a readily available neutral phenoxy-imine nickel catalyst, which significantly enables the formation of linear ultrahigh molecular weight polyethylene (~5 brs/1000C, M n = 1531 kDa) in a living polymerization (PDI = 1.08–1.11). An enhancement of 77 times on the polymer molecular weight occurs compared to the classical 2,6-diisopropyl substituted phenoxy-imine nickel catalyst. This avoids a tedious synthetic procedure and the use of an excess aluminum reagent as the activator and the scavenger. [ABSTRACT FROM AUTHOR]

In this article, a novel informative path planning (IPP) framework is proposed for efficient robotic object search. We innovatively reformulate the object search into an IPP problem, which takes account of the knowledge of possible target object locations. To model the target object distribution knowledge, the semantic information of the focused environment is utilized to obtain the probabilities of finding the target object at possible locations. Then, the probability distribution is modeled by Gaussian mixture model (GMM) to generate an information map. Based on the map, a sampling-based IPP method is proposed to minimize the object search cost. It is worth noting that the object search path is planned with a tree structure and evaluated by a utility function that concerns both search information gain and path cost. Moreover, to improve the quality of the search path, a novel informative sampling strategy and a rewire mechanism are conceived. The performance of the proposed object search framework is fully evaluated through both simulation experiments and real-world tests with a mobile robot platform. Results demonstrated that our method can find the target object efficiently and robustly with shorter path length than three comparative methods in the literature and the mobile robot shows human-like behavior when searching for the target object. [ABSTRACT FROM AUTHOR]

A fundamental challenge in video inpainting is the difficulty of generating video contents with fine details, while keeping spatio-temporal coherence in the missing region. Recent studies focus on synthesizing temporally smooth pixels by exploiting the flow information, while ignoring maintaining the semantic structural coherence between frames. This makes them suffer from over-smoothing and blurry contours, which significantly reduce the visual quality of inpainting results. To address this issue, we present a novel structure-guided video inpainting approach that enhances temporal structure coherence to improve video inpainting results. In contrast to directly synthesizing the missing pixel colors, we first complete edges in the missing regions to depict scene structures and object shapes via an edge inpainting network with 3D convolutions. Then, we replenish textures using a coarse-to-fine synthesis network with a structure attention module (SAM), under the guidance of the synthesized edges. Specifically, our SAM is designed to model the semantic correlation between video textures and structural edges to generate more realistic content. Besides, motion flows between neighboring frames are employed to enhance temporal consistency for self-supervision during training the edge inpainting and texture inpainting modules. Consequently, the inpainting results using our approach are visually pleasing with fine details and temporal coherence. Experiments on the YouTubeVOS, DAVIS, and 300VW datasets show that our method obtains state-of-the-art performance under diverse video inpainting settings. [ABSTRACT FROM AUTHOR]

Objectives: Dysfunction of autophagy results in accumulation of depolarized mitochondria and breakdown of self‐renewal and pluripotency in ESCs. However, the regulators that control how mitochondria are degraded by autophagy for pluripotency regulation remains largely unknown. This study aims to dissect the molecular mechanisms that regulate mitochondrial homeostasis for pluripotency regulation in mouse ESCs. Materials and methods: Parkin+/+ and parkin−/− ESCs were established from E3.5 blastocysts of parkin+/− x parkin+/− mating mice. The pink1−/−, optn−/− and ndp52−/− ESCs were generated by CRISPR‐Cas9. shRNAs were used for function loss assay of target genes. Mito‐Keima, ROS and ATP detection were used to investigate the mitophagy and mitochondrial function. Western blot, Q‐PCR, AP staining and teratoma formation assay were performed to evaluate the PSC stemness. Results: PINK1 or OPTN depletion impairs the degradation of dysfunctional mitochondria during reprogramming, and reduces the reprogramming efficiency and quality. In ESCs, PINK1 or OPTN deficiency leads to accumulation of dysfunctional mitochondria and compromised pluripotency. The defective mitochondrial homeostasis and pluripotency in pink1−/− ESCs can be compensated by gain expression of phosphomimetic Ubiquitin (Ub‐S65D) together with WT or a constitutively active phosphomimetic OPTN mutant (S187D, S476D, S517D), rather than constitutively inactive OPTN (S187A, S476A, S517A) or a Ub‐binding dead OPTN mutant (D477N). Conclusions: The mitophagy receptor OPTN guards ESC mitochondrial homeostasis and pluripotency by scavenging damaged mitochondria through TBK1‐activated OPTN binding of PINK1‐phosphorylated Ubiquitin. [ABSTRACT FROM AUTHOR]

An effective shielding of both apical positions of a neutral NiII active site is achieved by dibenzosuberyl groups, both attached via the same donors' N‐aryl group in a Cs‐type arrangement. The key aniline building block is accessible in a single step from commercially available dibenzosuberol. This shielding approach suppresses chain transfer and branch formation to such an extent that ultrahigh molecular weight polyethylenes (5×106 g mol−1) are accessible, with a strictly linear microstructure (<0.1 branches/1000C). Key features of this highly active (4.3×105 turnovers h−1) catalyst are an exceptionally facile preparation, thermal robustness (up to 90 °C polymerization temperature), ability for living polymerization and compatibility with THF as a polar reaction medium. [ABSTRACT FROM AUTHOR]

An effective shielding of both apical positions of a neutral NiII active site is achieved by dibenzosuberyl groups, both attached via the same donors' N‐aryl group in a Cs‐type arrangement. The key aniline building block is accessible in a single step from commercially available dibenzosuberol. This shielding approach suppresses chain transfer and branch formation to such an extent that ultrahigh molecular weight polyethylenes (5×106 g mol−1) are accessible, with a strictly linear microstructure (<0.1 branches/1000C). Key features of this highly active (4.3×105 turnovers h−1) catalyst are an exceptionally facile preparation, thermal robustness (up to 90 °C polymerization temperature), ability for living polymerization and compatibility with THF as a polar reaction medium. [ABSTRACT FROM AUTHOR]

Targeting energy metabolism holds the potential to effectively treat a variety of malignant diseases, and peroxisome proliferator-activated receptor gamma coactivator 1 alpha (PGC1α) is a key regulator of energy metabolism. However, PGC1α′s role in cancer, especially in hepatocellular carcinoma (HCC) remains largely unknown. In the present study, we reported that PGC1α was significantly downregulated in HCC cell lines and specimens. Moreover, reduced expression of PGC1α in tumor cells was correlated with poor prognosis. PGC1α overexpression substantially inhibited cell proliferation and induced apoptosis in vitro and in vivo. On the contrary, the knockdown of PGC1α produced the opposite effect. The mechanism was at least partially due to the upregulation of mitochondrial pyruvate carrier 1 (MPC1) caused by PGC1α, which promoted mitochondrial biogenesis by binding to nuclear respiratory factor 1 (NRF1). Consequently, the production of cellular reactive oxygen species (ROS) caused by mitochondrial oxidation was elevated above a critical threshold for survival. Furthermore, we found that PGC1α could enhance the antitumor activity of sorafenib and doxorubicin in HCC through ROS accumulation-mediated cell death. These results indicate that PGC1α/NRF1-MPC1 axis is involved in HCC progression and could be a promising target for HCC treatment. Image 1 • Low expression of PGC1α and MPC1 was associated with the poor prognosis of HCC. • PGC1α and MPC1 could inhibit HCC cell proliferation and induce apoptosis. • PGC1α/NRF1-MPC1 axis activates mitochondrial biogenesis and drives ROS production. • PGC1α/NRF1-MPC1 axis attenuates HCC progression. • PGC1α could enhance the sensitivity to sorafenib/doxorubicin treatment in HCC. [ABSTRACT FROM AUTHOR]

Autonomous 3-D exploration with unmanned aerial vehicles (UAVs) is increasingly prevalent for environment monitoring without human intervention. In this article, we present a systematic solution toward efficient UAV exploration in 3-D environments. Innovatively, a road map is incrementally built and maintained along with the exploration process, which explicitly exhibits the topological structure of the 3-D environment. By simplifying the environment, the road map can efficiently provide the information gain and the cost-to-go for a candidate region to be explored, which are two quantities for next-best-view (NBV) evaluation, thus prompting the efficiency for NBV determination. In addition, with reference to the global plan queried on the road map, we propose a local planner based on the potential field method that drives the robot to the information-rich area during the navigation process, which further improves the exploration efficiency. The proposed framework and its composed modules are verified in various 3-D environments, which exhibit their distinctive features in NBV selection and better performance in improving the exploration efficiency than other methods. [ABSTRACT FROM AUTHOR]

Branched polyolefin microstructures resulting from so‐called "chain walking" are a fascinating feature of late transition metal catalysts; however, to date it has not been demonstrated how desirable branched polyolefin microstructures can be generated thereby. We demonstrate how highly branched polyethylenes with methyl branches (220 Me/1000 C) exclusively and very high molecular weights (ca. 106 g mol−1), reaching the branch density and microstructure of commercial ethylene–propylene elastomers, can be generated from ethylene alone. At the same time, polar groups on the main chain can be generated by in‐chain incorporation of methyl acrylate. Key to this strategy is a novel rigid environment in an α‐diimine PdII catalyst with a steric constraint that allows for excessive chain walking and branching, but restricts branch formation to methyl branches, hinders chain transfer to afford a living polymerization, and inverts the regioselectivity of acrylate insertion to a 1,2‐mode. [ABSTRACT FROM AUTHOR]

Branched polyolefin microstructures resulting from so‐called "chain walking" are a fascinating feature of late transition metal catalysts; however, to date it has not been demonstrated how desirable branched polyolefin microstructures can be generated thereby. We demonstrate how highly branched polyethylenes with methyl branches (220 Me/1000 C) exclusively and very high molecular weights (ca. 106 g mol−1), reaching the branch density and microstructure of commercial ethylene–propylene elastomers, can be generated from ethylene alone. At the same time, polar groups on the main chain can be generated by in‐chain incorporation of methyl acrylate. Key to this strategy is a novel rigid environment in an α‐diimine PdII catalyst with a steric constraint that allows for excessive chain walking and branching, but restricts branch formation to methyl branches, hinders chain transfer to afford a living polymerization, and inverts the regioselectivity of acrylate insertion to a 1,2‐mode. [ABSTRACT FROM AUTHOR]

In order to make an accurate prediction of vehicle trajectory in a dynamic environment, a Unidirectional and Bidirectional LSTM (UB-LSTM) vehicle trajectory prediction model combined with behavior recognition is proposed, and then an acceleration trajectory optimization algorithm is proposed. Firstly, the interactive information with the surrounding vehicles is obtained by calculation, then the vehicle behavior recognition model is established by using LSTM, and the vehicle information is input into the behavior recognition model to identify vehicle behavior. Then, the trajectory prediction model is established based on Unidirectional and Bidirectional LSTM, and the identified vehicle behavior and the input information of the behavior recognition model are input into the trajectory prediction model to predict the horizontal and vertical speed and coordinates of the vehicle in the next 3 seconds. Experiments are carried out with NGSIM data sets, and the experimental results show that the mean square error (MSE) between the predicted trajectory and the actual trajectory obtained by this method is 0.124, which is 97.2% lower than that of the method that does not consider vehicle behavior and directly predicts the trajectory. The test loss is 0.000497, which is 95.68% lower than that without considering vehicle behavior. The predicted trajectory is obviously optimized, closer to the actual trajectory, and the performance is more stable. [ABSTRACT FROM AUTHOR]

The outcome predictors of intra‐aortic balloon pump (IABP) in patients who undergo mitral valve surgery remain unknown. This study aimed to retrospectively review valvular surgery in patients who received an IABP to identify the predictors of failure of IABP support and anticipate the necessary therapy. This retrospective observational study recruited a total of 157 consecutive patients who underwent open‐heart mitral valve surgery with IABP implantation intraoperatively or postoperatively. Univariate and multivariate logistic regression analyses were performed to identify the risk factors attributed to 30‐day mortality. Follow‐up data of survivors were collected to investigate the effect of IABP support to evaluate long‐term outcomes. The overall 30‐day mortality was 35.7% (56 patients). The following factors that contributed to 30‐day mortality included sepsis (P <.001, OR: 5.627, 95%CI: 2.422‐11.683); IABP implantation postoperatively rather than intraoperatively (P =.001, OR: 6.395, 95%CI: 2.085‐19.511); right heart failure (P =.042, OR: 3.419, 95%CI: 1.225‐12.257); and lack of subvalvular apparatus preservation (P =.033, OR: 3.710, 95%CI: 1.094‐13.167). Furthermore, follow‐up data of these patients showed an estimation of 5‐year and 10‐year survival rates of 58.9% and 35.7%, respectively. Patients with intraoperative IABP demonstrated better long‐term survival outcomes when compared to those with postoperative IABP (χ2 = 4.291, P =.038). In summary, this study distinguished the preoperative predictors of 30‐day mortality of IABP‐support in mitral valve surgery patients. These results indicated that early intervention with IABP should be taken into consideration in case of hemodynamic instability in critically ill patients undergoing mitral valve surgery. [ABSTRACT FROM AUTHOR]

As the analogues of classical α-diimine nickel catalysts, pyridine-imine nickel catalysts are of great interest for olefin polymerization to produce low molecular weight and branched polyethylenes. In this contribution, pyridine-imine nickel complexes Ni1–Ni4 bearing dibenzhydryl- and pentiptycenyl-N-aryl substituents and H- and Me-imine backbones were synthesized and systematically studied for ethylene polymerization. X-ray diffraction studies revealed that Ni1, Ni2 and Ni4 adopted a monoligated/binuclear structure, while Ni3 was found to adopt a monoligated/mononuclear structure, which differed from the bisligated/mononuclear mode reported previously. Upon activation with aluminum reagents such as Et2AlCl, MAO or MMAO, all these nickel complexes displayed very high activities (up to 14 530 kg mol−1 h−1) for ethylene polymerization. Branched (12–69/1000C) polyethylenes with low molecular weights (Mw: 0.7–22.1 kDa) were obtained with internal double bonds as the predominant unsaturated groups. The influences of the catalyst structure, type and amount of cocatalyst, time, temperature, pressure, and polar additive on the catalytic performances were thoroughly investigated. [ABSTRACT FROM AUTHOR]

Visual localization has been well studied in recent decades and applied in many fields as a fundamental capability in robotics. However, the success of the state of the arts usually builds on the assumption that the environment is static. In dynamic scenarios where moving objects are present, the performance of the existing visual localization systems degrades a lot due to the disturbance of the dynamic factors. To address this problem, we propose a novel sparse motion removal (SMR) model that detects the dynamic and static regions for an input frame based on a Bayesian framework. The similarity between the consecutive frames and the difference between the current frame and the reference frame are both considered to reduce the detection uncertainty. After the detection process is finished, the dynamic regions are eliminated while the static ones are fed into a feature-based visual simultaneous localization and mapping (SLAM) system for further visual localization. To verify the proposed method, both qualitative and quantitative experiments are performed and the experimental results have demonstrated that the proposed model can significantly improve the accuracy and robustness for visual localization in dynamic environments. [ABSTRACT FROM AUTHOR]

In this paper, we propose a novel path planning framework for autonomous exploration in unknown environments using a mobile robot. A graph structure is incrementally constructed along with the exploration process. The structure is the road map that represents the topology of the explored environment. To construct the road map, we design a sampling strategy to get random points in the explored environment uniformly. A global path from the current location of the robot to the target area can be found on this road map efficiently. We utilize a lazy collision checking method that only checks the feasibility of the generated global path to improve the planning efficiency. The feasible global path is further optimized with our proposed trajectory optimization method considering the motion constraints of the robot. This mechanism can facilitate the path cost evaluation for the next best view selection. In order to select the next best target region, we propose a utility function that takes into account both the path cost and the information gain of a candidate target region. Moreover, we present a target reselection mechanism to evaluate the target region and reduce the extra path cost. The efficiency and effectiveness of our approach are demonstrated using a mobile robot in both simulation and real experimental studies. Note to Practitioners—This paper is motivated by the efficient exploration problem, which plays a key role in various areas such as the information gathering and environment monitoring. In these applications, the mission length and executing time are often restricted by the battery capacity of the robot. In this paper, an efficient path planning framework is introduced to reduce the path length and exploration time. The robot keeps a road map of the environment to facilitate the path planning. The proposed target selection mechanism helps the robot determine the next best target to explore. Furthermore, the proposed trajectory optimization algorithm helps in reducing the path cost. Overall, this framework enables efficiently and autonomously exploration with a novel path planning framework. [ABSTRACT FROM AUTHOR]

DNA walking machines opened new avenues for the biosensing and demonstrated great success in the past few years. Since DNA machines are mainly nonequilibrium systems driven by dynamic interactions, the matrix effects on DNA machines is a bottleneck and more intricate than common DNA‐mediated assays, especially for complicated physiological samples. Herein, to realize an accurate and reliable quantitative machine, a ratiometric DNA walking machine was developed in human serums and cell lysates based on the elemental isotope ratio measurement. The target DNA‐triggered walking machine converted and amplified biological signals into mass spectrometric signal ratios (197Au/115In) via a burnt‐bridge mechanism. Under the optimized conditions, the limit of detection (LOD, 3σ) was 8 fM for target DNA, with a dynamic linear range of 0.05–0.7 pM. The ratiometric DNA walking machine was directly applied in human serum samples with satisfactory recoveries of 94 to 105 %, demonstrating an excellent stability and a high accuracy. Combining the aptamer‐based specific recognition, the proposed DNA machine is expected to be a versatile platform for other targets, such as small biomolecules and proteins. [ABSTRACT FROM AUTHOR]

Adenosine triphosphate is a major vector of chemical energy in living organisms, but its detection is sometimes hindered by complicated physiological sample matrixes. In this work, we demonstrated a ratiometric bioassay for the accurate and sensitive detection of ATP by measuring the 197Au/115In signal ratio of a mass spectrometric core–satellite structure. Validation of the proposed bioassay was successfully demonstrated in cell lysates and human serum samples. [ABSTRACT FROM AUTHOR]

Safe and socially compliant navigation in a crowded environment is essential for social robots. Numerous research efforts have shown the advantages of deep reinforcement learning techniques in training efficient policies, while most of them ignore fast-moving pedestrians in the crowd. In this paper, we present a novel design of safety measure, named Risk-Area, considering collision theory and motion characteristics of different robots and humans. The geometry of Risk-Area is formed based on the real-time relative positions and velocities of the agents in the environment. Our approach perceives risk in the environment and encourages the robot to take safe and socially compliant navigation behaviors. The proposed method is verified with three existing well-known deep reinforcement learning models in densely populated environments. Experiment results demonstrate that our approach combined with the reinforcement learning techniques can efficiently perceive risk in the environment and navigate the robot with high safety in the crowds with fast-moving pedestrians. [ABSTRACT FROM AUTHOR]

This paper presents the derivation of closed-form expressions for the interpretation of piezocone tests in clay on the basis of an undrained cavity expansion solution. The cavity expansion solution employs the modified Unified Hardening model to describe the undrained behaviour of normally- and over-consolidated clays upon shearing. The derived expressions correlate the measured tip resistance and pore pressure with the undrained shear strength and the over-consolidation ratio, using a cone factor that, unlike empirical formulas, is calculated directly from the constitutive model parameters and the cone geometry. The cavity expansion solution is validated via comparison of its results against published studies, and accordingly the accuracy of the proposed expressions is benchmarked against field data. We show that, despite the simplifications introduced in the derivation, the calibrated expressions are capable of reproducing the field data with reasonable accuracy. [ABSTRACT FROM AUTHOR]