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Glaucoma is a leading cause of irreversible blindness worldwide. While intraocular pressure (IOP) presents a major risk factor, the underlying pathophysiology still remains largely unclear. The correlation between vascular abnormalities and glaucoma has been deliberated for decades. Evidence for a role played by vascular factors in the pathogenesis of glaucomatous neurodegeneration has already been postulated. In addition, the fact that glaucoma causes both structural and functional changes to retinal blood vessels has been described. This review aims to investigate the published evidence concerning the relationship between vascular abnormalities and glaucoma, and to provide an overview of the "chicken or egg" dilemma in glaucoma. In this study, several biomarkers of glaucoma progression from a vascular perspective, including endothelin-1 (ET-1), nitric oxide, vascular endothelial growth factor (VEGF), and matrix metalloproteinases (MMPs), were identified and subsequently assessed for their potential as pharmacological intervention targets. [ABSTRACT FROM AUTHOR]

An essential aspect of human cognition is supported by a rich reservoir of abstract concepts without tangible external referents (e.g., "honor", "relationship", "direction"). While decades of research showed that the neural organization of conceptual knowledge referring to concrete words respects domains of evolutionary salience and sensorimotor attributes, the organization principles of abstract word meanings are poorly understood. Here, we provide neuropsychological evidence for a domain (sociality) and attribute (emotion) structure in abstract word processing. Testing 34 brain-damaged patients on a word-semantic judgment task, we observed double dissociations between social and nonsocial words and a single dissociation of sparing of emotional (relative to non-emotional) words. The lesion profiles of patients with specific dissociations suggest potential neural correlates positively or negatively associated with each dimension. These results unravel a general domain-attribute architecture of word meanings and highlight the roles of the social domain and the emotional attribute in the non-object semantic space. [ABSTRACT FROM AUTHOR]

Humans primarily rely on language to communicate, on the basis of a shared understanding of the basic building blocks of communication: words. Do we mean the same things when we use the same words? Although cognitive neural research on semantics has revealed the common principles of word-meaning representation, the factors underlying the potential individual variations in word meanings are unknown. Here, we empirically characterized the intersubject consistency of 90 words across 20 adult subjects (10 female) using both behavioral measures (rating-based semantic-relationship patterns) and neuroimaging measures (word-evoked brain activity patterns). Across both the behavioral and neuroimaging experiments, we showed that the magnitude of individual disagreements on word meanings could be modeled on the basis of how much language or sensory experience is associated with a word and that this variation increases with word abstractness. Uncovering the cognitive and neural origins of word-meaning disagreements across individuals has implications for potential mechanisms to modulate such disagreements. [ABSTRACT FROM AUTHOR]

The anterior temporal lobe (ATL) is engaged in various types of semantic dimensions. One consistently reported dimension is social information, with abstract words describing social behaviors inducing stronger activations in the ATL than nonsocial words. One potential factor that has been systematically confounded in this finding is emotional valence, given that abstract social words tend to be associated with emotional feelings. We investigated which factors drove the ATL sensitivity using a 2 (social/nonsocial) × 2 (valenced/neutral) factorial design in an fMRI study with relatively high spatial resolutions. We found that sociality and valence were processed in different ATL regions without significant interactions: The social effect was found in the left anterior superior temporal sulcus (aSTS), whereas the valence effect activated small clusters in the bilateral temporal poles (TP). In the left ATL, the social‐ and valence‐related clusters were distinct from another superior ATL area that exhibited a general "abstractness" effect with little modulation of sociality or valence. These subregions exhibited distinct whole‐brain functional connectivity patterns during the resting state, with the social cluster functionally connected to the default mode network, the valence cluster connected to the adjacent temporal regions and amygdala, and the abstractness cluster connected to a distributed network including a set of language‐related regions. These results of activation profiles and connectivity patterns together indicate that the way in which the left ATL supports semantic processing is highly fine‐grained, with the neural substrate for social semantic effects dissociated from those for emotional valence and abstractness. [ABSTRACT FROM AUTHOR]

Object conceptual processing has been localized to distributed cortical regions that represent specific attributes. A challenging question is how object semantic space is formed. We tested a novel framework of representing semantic space in the pattern of white matter (WM) connections by extending the representational similarity analysis (RSA) to structural lesion pattern and behavioral data in 80 brain-damaged patients. For each WM connection, a neural representational dissimilarity matrix (RDM) was computed by first building machine-learning models with the voxel-wise WM lesion patterns as features to predict naming performance of a particular item and then computing the correlation between the predicted naming score and the actual naming score of another item in the testing patients. This correlation was used to build the neural RDM based on the assumption that if the connection pattern contains certain aspects of information shared by the naming processes of these two items, models trained with one item should also predict naming accuracy of the other. Correlating the neural RDM with various cognitive RDMs revealed that neural patterns in several WM connections that connect left occipital/middle temporal regions and anterior temporal regions associated with the object semantic space. Such associations were not attributable to modality-specific attributes (shape, manipulation, color, and motion), to peripheral picture-naming processes (picture visual similarity, phonological similarity), to broad semantic categories, or to the properties of the cortical regions that they connected, which tended to represent multiple modality-specific attributes. That is, the semantic space could be represented through WM connection patterns across cortical regions representing modality-specific attributes. [ABSTRACT FROM AUTHOR]

The representation of object categories is a classical question in cognitive neuroscience and compelling evidence has identified specific brain regions showing preferential activation to categories of evolutionary significance. However, the potential contributions to category processing by tuning the connectivity patterns are largely unknown. Adopting a continuous multicategory paradigm, we obtained whole-brain functional connectivity (FC) patterns of each of four categories (faces, scenes, animals and tools) in healthy human adults and applied multivariate connectivity pattern classification analyses. We found that the whole-brain FC patterns made high-accuracy predictions of which category was being viewed. The decoding was successful even after the contributions of regions showing classical category-selective activations were excluded. We further identified the discriminative network for each category, which span way beyond the classical category-selective regions. Together, these results reveal novel mechanisms about how categorical information is represented in large-scale FC patterns, with general implications for the interactive nature of distributed brain areas underlying high-level cognition. Hum Brain Mapp 37:3685-3697, 2016. © 2016 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Near infrared (NIR) fluorescence imaging guided photodynamic therapy (PDT) is a technique which has been developed in many clinical trials due to its advantage of real-time optical monitoring, specific spatiotemporal selectivity, and minimal invasiveness. For this, photosensitizers with NIR fluorescence emission and high 1O2 generation quantum yield are highly desirable. Herein, we designed and synthesized a "donor–acceptor" (D-A) structured semiconductor polymer (SP), which was then wrapped with an amphiphilic compound (Pluronic ® F127) to prepare water-soluble nanoparticles (F-SP NPs). The obtained F-SP NPs exhibit good water solubility, excellent particle size stability, strong absorbance at deep red region, and strong NIR fluorescent emission characteristics. The maximal mass extinction coefficient and fluorescence quantum yield of these F-SPs were calculated to be 21.7 L/(g ⋅ cm) and 6.5%, respectively. Moreover, the 1O2 quantum yield of 89% for F-SP NPs has been achieved under 635 nm laser irradiation, which is higher than Methylene Blue, Ce6, and PpIX. The outstanding properties of these F-SP NPs originate from their unique D-A molecular characteristic. This work should help guide the design of novel semiconductor polymer for NIR fluorescent imaging guided PDT applications. [ABSTRACT FROM AUTHOR]

• Meta-analytic approach described the functional preference profiles in the ATL subregions. • We identified four functional subregions in the anterior temporal lobe (ATL). • We proposed sensory, language and socioemotion as the three dimensions that jointly depict the ATL functional specialization. The anterior temporal lobe (ATL) is involved in a wide range of cognitive processes but its functional specialization remains unclear. In this review, we synthesize evidence from cytoarchitecture, anatomical and functional connectivity, and functional activation to elucidate how subregions in the ATL contribute to various cognitive processes. Two complementary meta-analyses were conducted. We first constructed a comprehensive functional preference profile for all subregions through large-scale neuroimaging meta-analysis, and then employed a coordinate-based activation likelihood estimation analysis to examine such functional preferences by input types. We identified two subregions in the dorsal aspect of the ATL (i.e., superior dorsal, inferior dorsal) and two other subregions (lateral, ventromedial) in the ventral aspect of the ATL, all have distinct anatomical and functional preferences. We proposed sensory, language, and socioemotion as the three dimensions that jointly capture the cognitive components cutting across the four ATL subregions: the superior dorsal ATL was associated with auditory sensory, language (phonological production aspects), and emotion; the inferior dorsal ATL with auditory sensory and language (phonological perception and production aspects); the lateral ATL with visual sensory, language (semantic and episodic aspects), and social processing; and the ventromedial ATL with visual sensory, episodic memory, and emotion. The various functions associated with the ATL can be clustered into subregions, which provides sourceful basis for testing hypothesis-driven cognitive framework. [ABSTRACT FROM AUTHOR]

[Display omitted] • Molten-salt strategy is developed to introduce axial O ligand into PdN 4 sites. • Axial O ligand can activate the reaction activity and specificity of PdN 4 SACs. • O-PdN 4 -NGS displays remarkable 4e- ORR catalytic activity and selectivity. • Zn-air battery based on O-PdN 4 -NGS delivers superior stability compared to Pt/C. The absence of Pd ensemble sites and weak affinity for O-intermediates in tetracoordinate planar PdN 4 sites inhibit O-O bond dissociation and restrict 4e- oxygen reduction reaction (ORR) pathway. Optimizing the adsorption energy between O-intermediates and PdN 4 sites is a rational approach for selectively promoting 4e- ORR electrocatalysis. Herein, we propose a molten-salt strategy for introducing axial oxygen ligand into the PdN 4 sites to manipulate the electronic structure and create catalytic O-PdN 4 sites (one subsurface axial Pd-O configuration on PdN 4 plane) on N-doped graphene nanosheets (O-PdN 4 -NGS). Density functional theory calculations revealed that the axial Pd-O coordination can induce charge redistribution, downshift the d-band center of Pd and enhance the adsorption affinity of PdN 4 site for O-intermediates, thereby leading to superior electrocatalysis activity and selectivity for 4e- ORR process compared to conventional PdN 4 sites in 0.1 M KOH (with a positive half-wave potential E 1/2 of 0.90 V vs RHE). Moreover, zinc-air battery featuring with O-PdN 4 sites delivers a peak power density of 178 mW cm−2 at 227.5 mA cm−2 and stable long-term cycling performance, effectively showcasing the advantages of the axial O ligand modification in practical application. This work provides a constructive strategy to activate the reaction activity and specificity of PdN 4 single-atom sites by precisely-tuning the local coordination environment of Pd. [ABSTRACT FROM AUTHOR]

Atomically dispersed main group element single‐atom catalysts (SACs) have recently attracted increasing attention in electrocatalysis. However, their performances in acidic oxygen reduction reaction (ORR) remain unsatisfactory owing to the suboptimal coordination environment, limited mass transfer, and active site exposure. Herein, a series of p‐block Sn SACs with hierarchical pore structures are prepared by a dual melting salt‐mediated soft template method. By deliberately regulating the pore structures, highly exposed Sn active sites with N/O coordination are obtained, which endow SnN3O‐50 with exceptional ORR performances, especially in acidic medium. The half‐wave potential of SnN3O‐50 is up to 0.816 V, with a loss of only 15 mV after 10 000 potential cycles. Furthermore, the peak power densities of the fuel cell and zinc–air battery assembled using SnN3O‐50 as cathodes reach 502 and 173.5 mW cm−2, respectively, demonstrating great potential for practical applications. Density functional theory (DFT) calculations reveal that the N/O coordination of Sn induces localization of 5p electrons, which leads to strong coupling with the p orbit of O2. Meanwhile, the presence of defects synergistically regulates the adsorption of reaction intermediates, thereby optimizing the free energy of the four successive ORR steps. [ABSTRACT FROM AUTHOR]

The present study explored the relationship between visual dorsal stream and Chinese reading by resting-state fMRI technique. We collected the resting-state brain activities and reading skills of Chinese-speaking adult readers. The results showed that the values of amplitude of low frequency fluctuation (ALFF) in right posterior parietal cortex (PPC) and left visual middle temporal area (MT) (two regions of dorsal stream) were significantly correlated with rapid naming (RAN) speed, and the ALFF values of right PPC were correlated with orthographic awareness (OA). Further resting-state functional connectivity (RSFC) analysis revealed that RAN speed was related to RSFCs between dorsal stream areas and reading areas (e.g., left fusiform gyrus, bilateral middle occipital gyrus). OA was correlated with RSFCs between right PPC and left middle occipital gyrus. It suggested that spontaneous activities of visual dorsal stream, as well as connection between it and reading-related areas, were highly associated with Chinese reading skills. [ABSTRACT FROM AUTHOR]

The device based on PM6:Y6-eC6-HD achievesan outstandingpower conversion efficiency(PCE) of 16.00% with a high fill factor (FF) of 77.32%. [Display omitted] • The device based on PM6:Y6-eC6-HD afforded a PCE of 16.00% and a high FF of 77.32%. • Y6-eC6-HD possessed a high solubility and could be dissolved in green solvent. • Side chain engineering could improve the device performance, especially the FF. In recent years, the development of non-fullerene acceptor (NFA) has rapidly improved the power conversion efficiency (PCE) of organic solar cells (OSCs). However, there are still many factors restricting the further improvement of PCE, and the low fill factor (FF) value is one of the main reasons. Therefore, it is of great importance to increase FF through designing organic semiconducting materials. In this paper, Y6-eC6-HD is obtained by modifying two kinds of alkyl chains of Y6, because the regulation of the side alkyl chains as one of the effective methods can get proper film morphology which is beneficial for balanced charge transfer and improved FF. Subsequently, the device based on PM6:Y6-eC6-HD can achieve an outstanding PCE of 16.00% with a high FF of 77.32%. Such a high fill factor is higher than that of the most of Y-series molecules. These results indicate that adjusting the side alkyl chains of NFAs is a promising method to enhance the FF and therefore improving the PCE of OSCs. [ABSTRACT FROM AUTHOR]

Here, we describe a fluorination strategy for semiconducting polymers for the development of highly bright second near‐infrared region (NIR‐II) probes. Tetrafluorination yielded a fluorescence QY of 3.2 % for the polymer dots (Pdots), over a 3‐fold enhancement compared to non‐fluorinated counterparts. The fluorescence enhancement was attributable to a nanoscale fluorous effect in the Pdots that maintained the molecular planarity and minimized the structure distortion between the excited state and ground state, thus reducing the nonradiative relaxations. By performing through‐skull and through‐scalp imaging of the brain vasculature of live mice, we quantitatively analyzed the vascular morphology of transgenic brain tumors in terms of the vessel lengths, vessel branches, and vessel symmetry, which showed statistically significant differences from the wild type animals. The bright NIR‐II Pdots obtained through fluorination chemistry provide insightful information for precise diagnosis of the malignancy of the brain tumor. [ABSTRACT FROM AUTHOR]

Here, we describe a fluorination strategy for semiconducting polymers for the development of highly bright second near‐infrared region (NIR‐II) probes. Tetrafluorination yielded a fluorescence QY of 3.2 % for the polymer dots (Pdots), over a 3‐fold enhancement compared to non‐fluorinated counterparts. The fluorescence enhancement was attributable to a nanoscale fluorous effect in the Pdots that maintained the molecular planarity and minimized the structure distortion between the excited state and ground state, thus reducing the nonradiative relaxations. By performing through‐skull and through‐scalp imaging of the brain vasculature of live mice, we quantitatively analyzed the vascular morphology of transgenic brain tumors in terms of the vessel lengths, vessel branches, and vessel symmetry, which showed statistically significant differences from the wild type animals. The bright NIR‐II Pdots obtained through fluorination chemistry provide insightful information for precise diagnosis of the malignancy of the brain tumor. [ABSTRACT FROM AUTHOR]

In order to reveal the solidification behavior of Cr in the cement clinker mineral phase, 29Si magic-angle spinning nuclear magnetic resonance, X-ray diffraction, and scanning electron microscopy with energy-dispersive X-ray spectroscopy techniques were used to analyze the morphology and composition of the cement clinker mineral phase doped with Cr. The results showed that the addition of Cr did not change the chemical environment of 29Si in the clinker mineral phase, and it was still an isolated silicon–oxygen tetrahedron. Cr affected the orientation of the silicon–oxygen tetrahedron and the coordination number of calcium, leading to the formation of defects in the crystal structure of the clinker mineral phase, by replacing Ca2+ into the mineral phase lattice to form a new mineral phase Ca3Cr2(SiO4)3. Cr acted as a stabilizer for the formation of β-C2S in the clinker calcination. As the amount of Cr increased, the relative content of C3S decreased and the relative content of C2S increased. Further, Cr easily dissolved in C2S, while it was not found in C3S. This study is conducive to further research on the mechanism of heavy metal solidification in cement clinker. Furthermore, it is important to evaluate the environmental risk of heavy metals in the process of sludge disposal through cement kiln and promote the utilization of sludge resources and the sustainable development of the cement industry. [ABSTRACT FROM AUTHOR]

Purpose: To study the retinal and choroidal microvascular parameters in children with nephrotic syndrome (NS). Methods: This is a cross-sectional study. Optical coherence tomography angiography was used to evaluate the changes of retinal and choroidal microvessels in patients with NS. Thirty NS children and 20 normal controls were included in this study. The macular vessel density (VD) of the superficial capillary plexus (SCP), deep capillary plexus (DCP), choroid capillary plexus (CCP), and foveal avascular zone (FAZ) area of the SCP and DCP was quantitatively calculated. Clinical data including serum protein, blood lipid, uric acid, urea, serum creatinine, urinary protein concentration, urinary creatinine, 24-h urine volume, 24-h urinary total protein, 24-h creatinine clearance rate, and urinary albumin to creatinine ratio were collected. Results: The VDs of the DCP and CCP in children with NS were significantly lower than those in controls (59.35 ± 2.45 vs. 61.15 ± 1.53, p = 0.002, 66.34 ± 1.43 vs. 67.16 ± 1.23, p = 0.042, respectively). The VD of the SCP in children with NS had a tendency to decrease compared with that in controls, but there were no significant differences. There were also no significant differences in FAZ area between the two groups. The VD of the SCP was positively correlated with serum total protein (ρ = 0.446, p = 0.014), serum albumin (ρ = 0.431, p = 0.017), and 24-h urine volume (ρ = 0.389, p = 0.034) but negatively correlated with triglyceride (ρ = − 0.450, p = 0.013), low-density lipoprotein cholesterol (ρ = −0.432, p = 0.017), urinary protein concentration (ρ = − 0.606, p < 0.001), and 24-h urinary total protein (ρ = − 0.517, p = 0.004). The VDs of the SCP, DCP, and CCP were negatively correlated with the urinary albumin to creatinine ratio (ρ = − 0.473, p = 0.008, ρ = − 0.438, p = 0.015, ρ = −0.467, p = 0.009, respectively). Conclusions: Retinal and choroidal VDs were decreased in children with NS and paralleled the severity of kidney disease. Optical coherence tomography angiography can be used as a noninvasive method for evaluating renal injury in patients with NS. [ABSTRACT FROM AUTHOR]