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Bipolar electrochemistry (BE) combined with electrochemiluminescence (ECL) has gained considerable attention as a versatile and powerful analytical technique operating in a wireless manner. However, only co‐reactant ECL has been reported so far when using a BE setup. In this work, the generation of annihilation ECL at the anodic extremity of a bipolar electrode (BPE) is demonstrated in two different spatial arrangements of the electrodes. The reported approach is based on a synergetic effect between the asymmetric electroactivity induced across the BPE, which produces different redox states of [Ru(bpy)3]2+, and the electro‐migration mechanism of the formed ionic species, allowing the localization and concentration of the ECL emission. The presented approach demonstrating annihilation ECL via BE, paves the way for the design of easy and straightforward light‐emitting platforms for multiple applications. [ABSTRACT FROM AUTHOR]

Purpose: To demonstrate the feasibility of zigzag sampling for 3D rapid hyperpolarized 129Xe ventilation MRI in human. Methods: Zigzag sampling in one direction was combined with gradient‐recalled echo sequence (GRE‐zigzag‐Y) to acquire hyperpolarized 129Xe ventilation images. Image quality was compared with a balanced SSFP (bSSFP) sequence with the same spatial resolution for 12 healthy volunteers (HVs). For another 8 HVs and 9 discharged coronavirus disease 2019 subjects, isotropic resolution 129Xe ventilation images were acquired using zigzag sampling in two directions through GRE‐zigzag‐YZ. 129Xe ventilation defect percent (VDP) was quantified for GRE‐zigzag‐YZ and bSSFP acquisitions. Relationships and agreement between these VDP measurements were evaluated using Pearson correlation coefficient (r) and Bland–Altman analysis. Results: For 12 HVs, GRE‐zigzag‐Y and bSSFP required 2.2 s and 10.5 s, respectively, to acquire 129Xe images with a spatial resolution of 3.96 × 3.96 × 10.5 mm3. Structural similarity index, mean absolute error, and Dice similarity coefficient between the two sets of images and ventilated lung regions were 0.85 ± 0.03, 0.0015 ± 0.0001, and 0.91 ± 0.02, respectively. For another 8 HVs and 9 coronavirus disease 2019 subjects, 129Xe images with a nominal spatial resolution of 2.5 × 2.5 × 2.5 mm3 were acquired within 5.5 s per subject using GRE‐zigzag‐YZ. VDP provided by GRE‐zigzag‐YZ was strongly correlated (R2 = 0.93, p < 0.0001) with that generated by bSSFP with minimal biases (bias = −0.005%, 95% limit‐of‐agreement = [−0.414%, 0.424%]). Conclusion: Zigzag sampling combined with GRE sequence provides a way for rapid 129Xe ventilation imaging. [ABSTRACT FROM AUTHOR]

Prognosticating acute lung injury (ALI) is challenging, in part because of a lack of sensitive biomarkers. Hyperpolarized gas magnetic resonance (MR) has unique advantages in pulmonary function measurement and can provide promising biomarkers for the assessment of lung injuries. Herein, we employ hyperpolarized 129Xe MRI and generate a number of imaging biomarkers to detect the pulmonary physiological and morphological changes during the progression of ALI in an animal model. We find the measured ratio of 129Xe in red blood cells to interstitial tissue/plasma (RBC/TP) is significantly lower in the ALI group on the second (0.32 ± 0.03, p = 0.004), seventh (0.23 ± 0.03, p < 0.001), and 14th (0.29 ± 0.04, p = 0.001) day after lipopolysaccharide treatment compared with that in the control group (0.41 ± 0.04). In addition, significant differences are also observed for RBC/TP measurements between the second and seventh day (p = 0.001) and between the seventh and 14th day (p = 0.018) in the ALI group after treatment. Besides RBC/TP, significant differences are also observed in the measured exchange time constant (T) on the second (p = 0.038) and seventh day (p = 0.009) and in the measured apparent diffusion coefficient (ADC) and alveolar surface‐to‐volume ratio (SVR) on the 14th day (ADC: p = 0.009 and SVR: p = 0.019) after treatment in the ALI group compared with that in the control group. These findings indicate that the parameters measured with 129Xe MR can detect the dynamic changes in pulmonary structure and function in an ALI animal model. [ABSTRACT FROM AUTHOR]

Xiazhuang uranium ore field, located in the southern part of the Nanling Metallogenic Belt, is considered one of the largest granite‐related U regions in South China. In this paper, we contribute new apatite fission track data and thermal history modeling to constrain the exhumation history and evaluate preservation potential of the Xiazhuang Uranium ore field. Nine Triassic outcrop granite samples collected from different locations of Xiazhuang Uranium ore field yield AFT ages ranging from 43 to 24 Ma with similar mean confined fission track lengths ranging from 11.8 ± 2.0 to 12.9 ± 1.9 μm and Dpar values between 1.01 and 1.51 μm. The robustness time‐temperature reconstructions of samples from the hanging wall of Huangpi fault show that the Xiazhuang Uranium ore field experienced a time of monotonous and slow cooling starting from middle Paleocene to middle Miocene (∼60–10 Ma), followed by relatively rapid exhumation in the late Miocene (∼10–5 Ma) and nearly thermal stability in the Pliocene–Quaternary (∼5–0 Ma). The amount of exhumation after U mineralization since the Middle Paleogene was estimated as ∼4.3 ± 1.8 km according to the integrated thermal history model. Previous studies indicate that the ore‐forming ages of U deposits in the Xiazhuang ore field are mainly before Middle Paleocene and the mineralization depths are more than 4.4 ± 1.2 km. Therefore, the exhumation history since middle Paleocene plays important roles in the preservation of the Xiazhuang Uranium ore field. [ABSTRACT FROM AUTHOR]

The current field of human‐machine interaction (HMI) and electronic skin (e‐skin) is confronting challenges associated with energy supply, sensitivity, and biocompatibility. Traditional HMI systems, though rich in features, are constrained in their applications in the medical and wearable technology sectors due to their rigid structure and reliance on third‐party power inputs. Triboelectric nanogenerators (TENGs) based on natural materials are emerging as a focal point of research in this domain, attributed to their self‐powering capabilities, flexibility, and biocompatibility. These natural material‐based TENGs emulate the mechanical and biological characteristics of human skin, adapt to various body shapes and movements, and offer an efficient and reliable solution for the precise detection and analysis of complex, subtle physiological signals, thereby fostering innovations in wearable devices and robotic technology. This article provides a comprehensive review of recent advancements in natural material‐based TENGs, detailing the materials employed, including proteins, chitosan, and cellulose. It encapsulates their applications in the realms of electronic skin and HMI. Finally, the challenges confronted by natural material‐based TENGs are outlined and future trajectories for development in this burgeoning field are projected. [ABSTRACT FROM AUTHOR]

The concept of molecular design, integrating diagnostic and therapeutic functions, aligns with the general trend of modern medical advancement. Herein, we rationally designed the smart molecule ER‐ZS for endoplasmic reticulum (ER)‐targeted diagnosis and treatment in cell and animal models by combining hemicyanine dyes with ER‐targeted functional groups (p‐toluenesulfonamide). Owing to its ability to target the ER with a highly specific response to viscosity, ER‐ZS demonstrated substantial fluorescence turn‐on only after binding to the ER, independent of other physiological environments. In addition, ER‐ZS, being a small molecule, allows for the diagnosis of nonalcoholic fatty liver disease (NAFLD) via liver imaging based on high ER stress. Importantly, ER‐ZS is a type I photosensitizer, producing O2⋅− and ⋅OH under light irradiation. Thus, after irradiating for a certain period, the photodynamic therapy inflicted severe oxidative damage to the ER of tumor cells in hypoxic (2 % O2) conditions and activated the unique pyroptosis pathway, demonstrating excellent antitumor capacity in xenograft tumor models. Hence, the proposed strategy will likely shed new light on integrating molecular optics for NAFLD diagnosis and cancer therapy. [ABSTRACT FROM AUTHOR]

Activatable fluorescent and chemiluminescent dyes with near‐infrared emission have indispensable roles in the fields of bioimaging, molecular prodrugs, and phototheranostic agents. As one of the most popular fluorophore scaffolds, the dicyanomethylene‐4H‐pyran scaffold has been applied to fabricate a large number of versatile activatable optical dyes for analytes detection and diseases diagnosis and treatment by virtue of its high photostability, large Stokes shift, considerable two‐photon absorption cross‐section, and structural modifiability. This review discusses the molecular design strategies, recognition mechanisms, and both in vitro and in vivo bio‐applications (especially for diagnosis and therapy of tumors) of activatable dicyanomethylene‐4H‐pyran dyes. The final section describes the current shortcomings and future development prospects of this topic. [ABSTRACT FROM AUTHOR]

Background and Aims: The National Standardized Training for Resident Doctors (STRD) in mainland China encounters many challenges in its implementation. To investigate whether outpatients are willing to undergo indirect ophthalmoscopy examination conducted by ophthalmology residents in the ophthalmology STRD program in China. Methods: This study conducted a cross‐sectional survey at the Eye Hospital of Wenzhou Medical University between September 2021 and September 2023. A cohort of 300 initial outpatients requiring indirect ophthalmoscopy examinations were enlisted from the outpatient department. Based on whether the patients are willing to undergo an indirect ophthalmoscopy examination by resident doctors, patients were divided into two groups: Group 1 (willing) and Group 2 (unwilling), and their questionnaire responses were comparatively analyzed. Results: A total of 261/300 (87%) valid questionnaires were returned in the survey, which included 149 males and 112 females. No notable gender difference (p = 0.400) or disparity in medical expense categories (p = 0.786) was observed between the two groups. However, variables such as outpatient marital status (p = 0.002), the presence of training faculty during fundus examinations with residents and outpatients (p < 0.001), the demeanor of training residents toward patients (p < 0.001), and the quality of doctor–patient communication (p < 0.001) significantly varied between the groups. Conclusion: The level of outpatients' cooperation with ophthalmology residents during fundus examinations in the Chinese ophthalmology STRD program was observed to be low. Enhancing the presence of training faculty during examinations and enhancing the communication skills of training residents could significantly improve this situation. [ABSTRACT FROM AUTHOR]

The viscosity within cells is a crucial microenvironmental factor, and sulfur dioxide (SO2) has essential functions in regulating cellular apoptosis and inflammation. Some evidence has been confirmed that changes in viscosity and overexposure of SO2 within the cell may cause detrimental effects including, but not limited to, respiratory and cardiovascular illnesses, inflammation, fatty liver, and various types of cancer. Therefore, precise monitoring of SO2 and viscosity in biological entities holds immense practical importance. Therefore, in this research, we developed a versatile fluorescent TCF‐Cou that enables the dual detection of SO2 and viscosity in the living system. Probe TCF‐Cou possessed a response to viscosity and SO2 through red and green emissions. The alteration of SO2 and viscosity levels in live cells and zebrafish were also monitored using probe TCF‐Cou. We hope that this fluorescent probe could be a potential tool for revealing the related pathological and physiological processes through monitoring the changes in SO2 and viscosity. [ABSTRACT FROM AUTHOR]

Background: Hyperpolarized (HP) gas MRI enables the clear visualization of lung structure and function. Clinically relevant biomarkers, such as ventilated defect percentage (VDP) derived from this modality can quantify lung ventilation function. However, long imaging time leads to image quality degradation and causes discomfort to the patients. Although accelerating MRI by undersampling k‐space data is available, accurate reconstruction and segmentation of lung images are quite challenging at high acceleration factors. Purpose: To simultaneously improve the performance of reconstruction and segmentation of pulmonary gas MRI at high acceleration factors by effectively utilizing the complementary information in different tasks. Methods: A complementation‐reinforced network is proposed, which takes the undersampled images as input and outputs both the reconstructed images and the segmentation results of lung ventilation defects. The proposed network comprises a reconstruction branch and a segmentation branch. To effectively exploit the complementary information, several strategies are designed in the proposed network. Firstly, both branches adopt the encoder‐decoder architecture, and their encoders are designed to share convolutional weights for facilitating knowledge transfer. Secondly, a designed feature‐selecting block discriminately feeds shared features into decoders of both branches, which can adaptively pick suitable features for each task. Thirdly, the segmentation branch incorporates the lung mask obtained from the reconstructed images to enhance the accuracy of the segmentation results. Lastly, the proposed network is optimized by a tailored loss function that efficiently combines and balances these two tasks, in order to achieve mutual benefits. Results: Experimental results on the pulmonary HP 129Xe MRI dataset (including 43 healthy subjects and 42 patients) show that the proposed network outperforms state‐of‐the‐art methods at high acceleration factors (4, 5, and 6). The peak signal‐to‐noise ratio (PSNR), structural similarity (SSIM), and Dice score of the proposed network are enhanced to 30.89, 0.875, and 0.892, respectively. Additionally, the VDP obtained from the proposed network has good correlations with that obtained from fully sampled images (r = 0.984). At the highest acceleration factor of 6, the proposed network promotes PSNR, SSIM, and Dice score by 7.79%, 5.39%, and 9.52%, respectively, in comparison to the single‐task models. Conclusion: The proposed method effectively enhances the reconstruction and segmentation performance at high acceleration factors up to 6. It facilitates fast and high‐quality lung imaging and segmentation, and provides valuable support in the clinical diagnosis of lung diseases. [ABSTRACT FROM AUTHOR]

Excited‐state intramolecular proton transfer (ESIPT)‐based solid luminescent materials with multiple hydrogen bond acceptors (HBAs) remain unexplored. Herein, we introduced a family of Janus‐type ESIPT chromophores featuring distinctive hydrogen bond (H‐bond) selectivity between competitive HBAs in a single molecule. Our investigations showed that the central hydroxyl group preferentially forms intramolecular H‐bonds with imines in imine‐modified 2‐hydroxyphenyl benzothiazole (HBT) chromophores but tethers the benzothiazole moiety in hydrazone‐modified HBT chromophores. Imine‐derived HBTs generally exhibit higher fluorescence efficiency, while hydrazone‐derived HBTs show a reduced overlap between the absorption and fluorescence bands. Quantum chemical calculations unveiled the molecular origins of the biased intramolecular H‐bonds and their impact on the ESIPT process. This Janus‐type ESIPT chromophore skeleton provides new opportunities for the design of solid luminescent materials. [ABSTRACT FROM AUTHOR]

With the intensification of global environmental issues, corporate environmental information disclosure has received increasing attention. Different cultural and policy backgrounds have led to very different styles of corporate environmental information disclosure behavior. Whether Confucianism, the dominant culture that has influenced China for thousands of years, contributes to corporate environmental information disclosure deserves to be studied. Based on data from 3180 Chinese listed firms, this study confirms the positive effect of Confucian culture on environmental information disclosure. Meanwhile, Taoist culture and environmental regulation can positively moderate this effect. In addition, heterogeneity analysis unveils that Confucian culture plays a greater role in corporate environmental information disclosure for state‐owned firms and firms in highly polluting industries, while this role is weakened for firms with a high proportion of female executives and executives with foreign experience. This study links culture and environmental information disclosure, which helps to arouse the attention of whole society to utilize excellent traditional culture and helps the government to formulate effective environmental regulation policies. [ABSTRACT FROM AUTHOR]

Membrane curvature reflects physical forces operating on the lipid membrane, which plays important roles in cellular processes. Here, we design a mechanosensitive DNA (MSD) nanomachine that mimics natural mechanosensitive PIEZO channels to convert the membrane tension changes of lipid vesicles with different sizes into fluorescence signals in real time. The MSD nanomachine consists of an archetypical six‐helix‐bundle DNA nanopore, cholesterol‐based membrane anchors, and a solvatochromic fluorophore, spiropyran (SP). We find that the DNA nanopore effectively amplifies subtle variations of the membrane tension, which effectively induces the isomerization of weakly emissive SP into highly emissive merocyanine isomers for visualizing membrane tension changes. By measuring the membrane tension via the fluorescence of MSD nanomachine, we establish the correlation between the membrane tension and the curvature that follows the Young‐Laplace equation. This DNA nanotechnology‐enabled strategy opens new routes to studying membrane mechanics in physiological and pathological settings. [ABSTRACT FROM AUTHOR]

Cancer immunotherapy has been a revolutionary cancer treatment modality because it can not only eliminate primary tumors but also prevent metastases and recurrent tumors. Immunogenic cell death (ICD) induced by various treatment modalities, including chemotherapy, phototherapy, and radiotherapy, converts dead cancer cells into therapeutic vaccines, eliciting a systemic antigen‐specific antitumor. However, the outcome effect of cancer immunotherapy induced by ICD has been limited due to the low accumulation efficiency of ICD inducers in the tumor site and concomitant damage to normal tissues. The boom in smart nanomaterials is conducive to overcoming these hurdles owing to their virtues of good stability, targeted lesion site, high bioavailability, on‐demand release, and good biocompatibility. Herein, the design of targeted nanomaterials, various ICD inducers, and the applications of nanomaterials responsive to different stimuli, including pH, enzymes, reactive oxygen species, or dual responses are summarized. Furthermore, the prospect and challenges are briefly outlined to provide reference and inspiration for designing novel smart nanomaterials for immunotherapy induced by ICD. [ABSTRACT FROM AUTHOR]

How to inspire firms to conduct green innovation is still an under‐explored question. This study finds that the green concerns of minority shareholders can significantly promote firms to conduct green innovation. Mechanism tests reveal that green concerns promote firm green innovation by increasing media attention and reducing financing constraints. Further research shows that the positive effect of green concerns of minority shareholders on green innovation is more significant for companies with high competition, more effective internal controls, and high public involvement at the location. Based on the findings, policy implications of promoting corporate green innovation are discussed. [ABSTRACT FROM AUTHOR]

Engineering the morphology of naturally abundant transition metal sulfides is an effective strategy to improve their electrocatalytic activity. In this work, lumpy-, coral-, and flower-like Fe0.95S1.05 catalysts were successfully prepared using a one-pot solvothermal method through the decomposition of iron thiolato carbonyl complexes (Fe2S2(CO)6) in different solvents. Then, the structural and morphological characteristics of the nanomaterials were comprehensively investigated by a series of state-of-the-art techniques. The results showed that the formed flower-like Fe0.95S1.05 nanosheets had a high surface area of 63.7 m2 g−1 and a low contact angle of 15.4°, and a greater number of d orbitals of Fe2+ and Fe3+ overlapped on the surface. Correspondingly, this catalyst exhibited enhanced oxygen evolution reaction and hydrogen evolution reaction activities with a current density of 10 mA cm−2 at overpotentials of 280 and 345 mV, respectively, and these values were lower than those of lumpy- and coral-like Fe0.95S1.05. When flower-like Fe0.95S1.05 was assembled as the anode and cathode catalysts, overall water splitting efficiency was achieved at 1.68 V at 10 mA cm−2. This study provides a simple and low-cost approach for preparing efficient pyrrhotite FeS-based electrocatalysts for water splitting. [ABSTRACT FROM AUTHOR]

Vegetation restoration is one of the effective measures to deal with land degradation, and shrubs, as the pioneer plants, can improve soil conditions and accelerate the recovery of desertification. In recent decades, single‐scan (SS) and multiple‐scan (MS) modes have been widely used for forest inventories by terrestrial laser scanner (TLS) but TLS‐based shrub observation, and data quality uncertainties are less studied, especially in eco‐fragile regions with high survey costs and harsh environmental conditions. In this study, two shrub sample plots with different topographic characteristics were selected as the study area in the southern Qinghai‐Tibetan Plateau. We compared the basic phenotypic parameters (BPPs) under SS and MS mode, including number (N), height (H) and crown width (CW), to evaluate the potential of SS mode in extracting vegetation attributes. Through the distribution of shrub information loss rate (L) with distance and shrub height, the limitations of SS mode in obtaining data were discussed. By combining the topographic features of scanning spots, topographic relief (T) and L, we provided reasonable opinions on TLS collection mode, setting of scanning spots, and other operational aspects. The results indicated that: (1) SS mode has good applicability in shrub observation under different terrain characteristics. (2) The height distribution of the shrub is the main factor affecting the quality of data collection, and the information loss bias caused by distance should be considered only in the shrub plots with uniform height distribution. (3) T has an impact on shrub growth but has no effect on the quality of data acquisition (no significant correlation between T and L). These findings will provide technical support for TLS data collection on ecological restoration of degraded grassland dunes. [ABSTRACT FROM AUTHOR]

Noninvasive treatments for terminal cancer patients constitute a new trend in tumor treatment. Therefore, phototherapy, including photodynamic therapy (PDT) and photothermal therapy (PTT), has attracted considerable interest. Light and a photosensitizer (PS) are employed in both treatment methods. For PDT, the PS generates reactive oxygen species (ROS) when exposed to light, whereas for PTT, the PS generates heat. In this regard, the systematic design of new PSs has become an active area of phototherapy research in an effort to solve the problems associated with conventional PSs. In the past decade, activatable and heavy‐atom‐free PSs have become significant research areas. Therefore, we discuss our recent contributions to the PDT and PTT in this account. [ABSTRACT FROM AUTHOR]

Purpose. To investigate the relationship between aqueous humor cytokines and structural characteristics based on optical coherence tomography (OCT) in patients with diabetic macular edema (DME). Methods. Forty eyes of 28 patients with DME diagnosed in the Affiliated Eye Hospital of Wenzhou Medical University at Hangzhou were included. All patients collected aqueous humor during anti-VEGF treatment, and the IL-6, IL-8, IL-10, VEGF, VCAM-1, ICAM-1, TGF-β1, FGF, and MCP-1 concentrations were detected. OCT examination was performed before anti-VEGF treatment and 1 month after anti-VEGF operation. Central macular thickness (CMT), macular volume (MV), choroidal thickness (CT), and the number of hyperreflective foci (HRF) were obtained for analysis. Each eye was determined whether there is subretinal effusion (SRD), cystoid macular edema (CME), and diffuse retinal thickening (DRT). Results. The levels of IL-6 and FGF in DME patients with SRD were significantly higher than those without SRD (all P < 0.05). The level of VEGF in DME patients with CME was significantly higher than that in DME patients without CME (P = 0.005); IL-6, TGF-β1, and MCP-1 were significantly higher in DME patients with DRT than that without DRT (all P < 0.05). There was no significant correlation between aqueous humor cytokines and retinal thickness and retinal volume. However, the thinner the CT, the higher the level of aqueous humor cytokines IL-6 (r = −0.313, P = 0.049) and FGF (r = −0.361, P = 0.022). A multivariate linear regression analysis showed that IL-6 was significantly correlated with CT (P = 0.002) and SRD (P = 0.017), FGF was also significantly correlated with CT (P = 0.002) and SRD (P = 0.005), and TGF-β1 was correlated with triglycerides (P = 0.030) and HRF (P = 0.021). Conclusion. DME patients with significant macular cystoid edema changes may be related to high VEGF concentrations and thin CT; meanwhile, the presence of SRD or a high number of HRF on OCT macular scans in DME patients may indicate high levels of intraocular inflammatory factors. Thus, OCT morphology characteristics to some extent reflect intraocular inflammatory factors and VEGF levels and may guide treatment alternatives. [ABSTRACT FROM AUTHOR]

Polybenzoxazines have a variety of advantages over most polymers, but the brittle feature limits the range of their applications. The most effective way for benzoxazine toughing is to copolymerize them with a well‐designed benzoxazine monomer able to contribute self‐plasticizing action. Here, a new bio‐based benzoxazine was synthesized from diphenolic acid (DPA), the sustainable candidate of bisphenol A. By introducing three aliphatic chains into DPA, the special benzoxazine able to provide remarkable toughness effect is obtained. For the synthesis, DPA is amidated using lauryl amine to diphenolic lauramide (DLA) first, then convert to a benzoxazine (DLA‐la) by Mannich‐like reaction with lauryl amine and paraformaldehyde. A commercial benzoxazine, bis(4‐(2H‐benzo[e][1,3]oxazin‐3(4H)‐yl)phenyl)methane (PH‐ddm), is employed as the toughing object to test the possibility of using DLA‐la would offer a significant toughing effect. Experimental results show that DLA‐la/PH‐ddm blending would result in a perfect resin without phase separation, which exhibits an improved elongation at break higher by 70.5% than the bulk PH‐ddm resin, while keeps tensile strength at 44.69 MPa. As the proposed toughing principle could be applied to a variety of commercially available benzoxazines, this research broadly contributes toward the development of benzoxazine industries. [ABSTRACT FROM AUTHOR]

Novel interactions between introduced oaks and their natural enemies across different continents provide an opportunity to test the enemy release hypothesis (ERH) at local and global scales. Based on the ERH, we assessed the impacts of native seed‐feeding insects on introduced and native oaks within and among continents. We combined a common‐garden experiment in China and biogeographic literature surveys to measure seed predation by insects and the proportion of acorn embryos surviving after insect infestation among 4 oak species with different geographical origins: Quercus mongolica origin from China, Q. robur and Q. petraea from Europe, and Q. rubra from North America. Mostly supporting the ERH, oaks in introduced continents escaped seed predation compared to those in native continents and compared to other native oaks in introduced continents. Common‐garden comparisons showed that total acorn infestation rate of introduced Q. rubra (section Lobatae) was considerably lower than that of native oaks (section Quercus) in China and Europe, likely because of the differences in seed traits associated with different oak sections. Literature surveys showed that seed predation of introduced oaks was lower in the introduced continent than in the native continent. Embryo survival was higher in introduced Q. rubra than native oaks in China and Poland. However, insect seed predation of recently introduced Q. rubra in China was similar to that in Europe, which is not consistent with the ERH. Our results suggest that reduced acorn attack by native insects and higher embryo survival after acorn damage could increase the establishment success or invasion risk of introduced oaks in non‐native continents. [ABSTRACT FROM AUTHOR]

Purpose: Radiation‐induced lung injury (RILI) is a common side effect in patients with non‐small cell lung cancer (NSCLC) treated with radiotherapy. Minimizing irradiation into highly functional areas of the lung may reduce the occurrence of RILI. The aim of this study is to evaluate the feasibility and utility of hyperpolarized xenon‐129 magnetic resonance imaging (MRI), an imaging tool for evaluation of the pulmonary function, to guide radiotherapy planning. Methods: Ten locally advanced NSCLC patients were recruited. Each patient underwent a simulation computed tomography (CT) scan and hyperpolarized xenon‐129 MRI, then received 64 Gyin 32 fractions for radiotherapy. Clinical contours were drawn on CT. Lung regions with good ventilation were contoured based on the MRI. Two intensity‐modulated radiation therapy plans were made for each patient: an anatomic plan (Plan‐A) based on CT alone and a function‐based plan (Plan‐F) based on CT and MRI results. Compared to Plan‐A, Plan‐F was generated with two additional steps: (1) beam angles were carefully chosen to minimize direct radiation entering well‐ventilated areas, and (2) additional optimization criteria were applied to well‐ventilated areas to minimize dose exposure. V20Gy, V10Gy, V5Gy, and the mean dose in the lung were compared between the two plans. Results: Plan‐A and Plan‐F were both clinically acceptable and met similar target coverage and organ‐at‐risk constraints (p > 0.05) except for the ventilated lungs. Compared with Plan‐A, V5Gy (Plan‐A: 30.7 ± 11.0%, Plan‐F: 27.2 ± 9.3%), V10Gy (Plan‐A: 22.0 ± 8.6%, Plan‐F: 19.3 ± 7.0%), and V20Gy (Plan‐A: 12.5 ± 5.6%, Plan‐F: 11.0 ± 4.1%) for well‐ventilated lung areas were significantly reduced in Plan‐F (p < 0.05). Conclusion: In this pilot study, function‐based radiotherapy planning using hyperpolarized xenon‐129 MRI is demonstrated to be feasible in 10 patients with NSCLC with the potential to reduce radiation exposure in well‐ventilated areas of the lung defined by hyperpolarized xenon‐129 MRI. [ABSTRACT FROM AUTHOR]

The intestinal microbiota play a vital role in the growth and health of the host. Probiotics could influence the homeostasis of intestinal microbiota, but the relationship between species and ecosystem stability is poorly understood. Here, four diets with different doses of Bacillus cereus (control, 0 cfu/kg; BL7, 107 cfu/kg; BL9, 109 cfu/kg; and BL11, 1011 cfu/kg) were designed to investigate the intestinal microbiota in Paramisgurnus dabryanus. The growth experiment demonstrated that the growth performance and the indices of Chao1, phylogenetic diversity, Simpson and Shannon improved significantly after loaches were fed a BL11 diet. The dominant composition of intestinal microbiota at phylum, class and genus levels did not change in loach after feeding different diets. Categories of bacterial taxa revealed that rare taxa and conditionally rare taxa were the dominant bacterial taxa in intestinal microbiota of loach. B. cereus supplemented with 1011 cfu/kg promoted the stability of the ecological network of intestinal microbiota by reinforcing the cooperation of interspecific interactions, promoting operational taxonomic units to shape larger submodules and increasing module hubs species and connectors species. Results of functional prediction revealed that a total of 5692 functions were shared among the four groups, which accounted for 91.7% of overall functions. To sum up, dietary supplementation with B. cereus had no significant influences on the composition and bacterial taxa of intestinal microbiota and the composition of bacterial functions. A dose of B. cereus appropriate to the diet could improve the growth performance and promote the homeostasis of intestinal microbiota in loach. [ABSTRACT FROM AUTHOR]

Altered intestinal microbial composition promotes intestinal barrier dysfunction and triggers the initiation and recurrence of inflammatory bowel disease (IBD). Current treatments for IBD are focused on control of inflammation rather than on maintaining intestinal epithelial barrier function. Here, we show that the internalization of Gram‐negative bacterial outer membrane vesicles (OMVs) in human intestinal epithelial cells promotes recruitment of caspase‐5 and PIKfyve to early endosomal membranes via sorting nexin 10 (SNX10), resulting in LPS release from OMVs into the cytosol. Caspase‐5 activated by cytosolic LPS leads to Lyn phosphorylation, which in turn promotes nuclear translocalization of Snail/Slug, downregulation of E‐cadherin expression, and intestinal barrier dysfunction. SNX10 deletion or treatment with DC‐SX029, a novel SNX10 inhibitor, rescues OMV‐induced intestinal barrier dysfunction and ameliorates colitis in mice by blocking cytosolic LPS release, caspase‐5 activation, and downstream signaling. Our results show that targeting SNX10 may be a new therapeutic approach for restoring intestinal epithelial barrier function and promising strategy for IBD treatment. SYNOPSIS: Sorting nexin 10 (SNX10) mediates Gram‐negative bacteria‐induced intestinal epithelial barrier dysfunction via the PIKfyve‐caspase‐5‐Lyn‐Snail/Slug‐E‐cadherin signaling axis. Deletion or chemical inhibition of SNX10 restores intestinal epithelial barrier function in murine colitis models. SNX10 acts as an adaptor protein to assemble a complex containing PIKfyve, caspase‐5 and Lyn for LPS release, sensing and signaling transduction.SNX10 promotes caspase‐5 activation and Lyn phosphorylation to regulate nuclear trans‐localization of Snail/Slug leading to downregulation of E‐cadherin expression and impaired intestinal epithelial barrier function.SNX10 deletion or DC‐SX029 treatment maintains intestinal epithelial barrier function and ameliorate colitis in mice. [ABSTRACT FROM AUTHOR]

Near‐infrared (NIR) activatable fluorescent probes have been considered to be the effective edge tools for the investigation of cell biology and disease diagnosis because of their outstanding advantages. Related genes involved in tumor genesis and progression regulate the overexpression of certain enzymes. Owing to the distinctive characteristics of quick reaction time and favorable pharmacokinetics, enzyme‐reactive NIR optical probes have shown great potential in the diagnosis of tumorigenesis and in image‐guided intraoperative surgeries with high signal‐to‐noise ratios. In this review, we mainly summarize the latest advancements in enzyme‐reactive NIR fluorescent probes from design strategy to biomedical application. Specifically, some challenges and prospects in this field are presented at the end of the review, which will be beneficial to innovatively construct new multifunctional fluorescent probes and actively promote their clinical transformation in the future. [ABSTRACT FROM AUTHOR]

Selective fluorescence imaging of biomarkers in vivo and in situ for evaluating orthotopic hepatocellular carcinoma (HCC) chemotherapy remains a great challenge due to current imaging agents suffering from the potential interferences of other hydrolases. Herein, we observed that carbamate unit showed a high selectivity toward the HCC‐related biomarker carboxylesterase (CE) for evaluation of treatment. A near‐infrared two‐photon fluorescent probe was developed to not only specially image CE activity in vivo and in situ but also target orthotopic liver tumor after systemic administration. The in vivo signals of the probe correlate well with tumor apoptosis, making it possible to evaluate the status of treatment. The probe enables the imaging of CE activity in situ with a high‐resolution three‐dimensional view for the first time. This study may promote advances in optical imaging approaches for precise imaging‐guided diagnosis of HCC in situ and its evaluation of treatment. [ABSTRACT FROM AUTHOR]

Nowadays, photocatalytic technology is considered as one of the most efficient methods to solve the problem of the global energy shortage and the pollution of the environment. Among these outstanding photocatalysts, metal sulfide‐based semiconductors have attracted wide attention because of their good chemical stability, simple synthesis method, and relatively narrow bandgaps. ZnIn2S4 (ZIS), as a layered structure ternary metal chalcogenide and a rising material star, has made exciting breakthroughs in the past decades. Recently, studies have shown that a rich variety of ZIS composite nanostructures are developed. This review summarizes the recent advances and development in the design and improvement of ZIS and ZIS‐based photocatalysts in full‐spectrum photocatalytic applications. Furthermore, the applications of ZIS‐based photocatalysts are discussed, such as in photocatalytic hydrogen production, CO2 reduction, degradation of pollutants, and photocatalytic selective organic transformations under ultraviolett (UV), visible (Vis), and near‐infrared (NIR) light irradiation. In the end, a brief summary and perspectives on the challenges and future directions in the area of ZIS and ZIS‐based photocatalysts are also provided. [ABSTRACT FROM AUTHOR]

The creation of microwells on an electrode surface has been used to improve the electrode performance. Herein, we report the fabrication of a microwell bipolar electrode array (MBEA) by selectively etching a fiber core and coating a thin gold layer on one pole of optical fiber bundle. The remote electrochemiluminescence (ECL) sensing platform is developed with the combination of the MBEA and ECL, such that light emission is generated at the distal face of the optical fiber bundle and detected at its proximal face. The resulting microwells in the MBEA can enhance the ECL generation, and produce a bell‐like ECL emission, for which higher light intensity is measured in the center of the fiber core than around its periphery. Then, it is revealed in theoretical simulations that the parabolic‐shaped bottom in the microwell induces the strong overlapped diffusion fields in its center and promotes the generation of ECL there. Finally, the application of MBEA is demonstrated in the detection of nicotinamide adenine dinucleotide (NADH). [ABSTRACT FROM AUTHOR]

The Tibetan Plateau, a vulnerable eco‐region undergoing global change, is hard to revegetate where land has become desertified due to the harsh habitat conditions. Sophora moorcroftiana shrubs, which are widely distributed in the middle reaches of the Yarlung Zangbo River basin of Tibet, China, have been naturally restored on desertified land during the last few decades. However, the influences of micro‐topography on the distribution and structure of the S. moorcroftiana population have been rarely reported. Here, we first describe the spatial variation of S. moorcroftiana population on a restored alluvial fan, and then explore the effects of micro‐topography on the restored S. moorcroftiana population, through a series of field surveys combined with the data collected by terrestrial laser scanning. The results indicate that the dominant age structure was adult shrubs (30–60 cm). Although the topographic effect had no significant impacts on soil organic matter and some other structural traits, which remained stable on the restored alluvial fan, it changed population density, plant growth, and distribution. The habitat conditions on the southwest aspect wapproximately 20°–25° slope with altitudes ranging between 3,593–3,643 m, conditions that mostly favouring the distribution of the shrub population. The micro‐topography played an important role in species distribution and growth of the S. moorcroftiana population. Our findings could help to understand the effect of micro‐topography on plant population structure and distribution for ecological restoration of desertified land in the Southern Tibetan Plateau. [ABSTRACT FROM AUTHOR]

A 42‐day feeding trial was conducted to investigate the effects of supplementation with various additives from Bacillus cereus A4 (fermentation supernatant, FS; live cells, BC; spores, BS; and cell‐free extract, CE) on the growth performance, intestinal morphology, digestive enzyme activities, immune responses and disease resistance of Litopenaeus vannamei (initial weight approximately 2.34 g). The results indicated that the growth performance of shrimp in BC, BS and CE groups improved significantly and no significant difference was observed between the control and FS groups. The villus height of the shrimp mid‐intestine in the FS, BC, BS and CE groups improved significantly compared with the control, and the maximum intestinal wall thickness was observed in BS group. Compared to the control, the activities of amylase, trypsin, lipase, acid phosphatase (ACP), alkaline phosphatase (AKP), superoxide dismutase, lysozyme and total nitric oxide synthase and the relative expression levels of Immune deficiency (Imd), Toll and Relish genes in shrimp of BC, BS and CE groups enhanced significantly. The activities of amylase, trypsin, ACP, AKP and the relative expression levels of Imd, Toll and Relish genes in shrimp of BC and BS groups were significantly higher than those of other groups. In the challenge test against Vibrio parahaemolyticus, the cumulative mortality of shrimp in BC and BS groups was significantly lower compared with that of other groups. Thus, the live cells and spores of B. cereus A4 provided superior probiotic benefits to L. vannamei, including improvements in growth, intestinal morphology, digestive enzyme activities, disease resistance and immune responses. [ABSTRACT FROM AUTHOR]

The efficiency of ecosystem restoration of degraded land is typically assessed using vegetation structure parameters (VSP). However, the field measurement of VSP, particularly in the Qinghai–Tibet Plateau (QTP), which is a problematic area for ecological restoration because of its harsh environment, is generally time‐consuming and labour intensive. Therefore, new methods for VSP measurement should be developed. In this study, VSP were quantified at the individual scale, including their number, height, and crown width. Furthermore, the quadrat scale, such as vegetation coverage (VC) and leaf area index (LAI) on a restored sandy plot (100 m × 100 m) in the middle reaches of the Yarlung Zangbo River basin, is quantified using terrestrial laser scanning. Thereafter, the TLS‐derived VSP are validated by field measurements. To extract the VSP of low‐height vegetation (shrubs) at the individual scale, three approaches are tested: the manual measurement of VSP from TLS data, individual vegetation segmentation (IVS) without specific root locations, and IVS with specific root locations. The results indicate that the VSP of shrubs can be manually derived from the TLS data and are consistent with field measurements. By specifying the root locations before performing the IVS, the identification rate of the number of shrubs can be improved significantly from 40.3% to 100%. The height extracted by the IVS corresponds better with the manual measurement (R2 > 0.99) than with the crown width (R2 < 0.65). At the quadrat scale, the optimal resolution is analyzed to extract the VC. The analysis suggests that the optimal resolution for extracting the VC based on the canopy height model is in the 1‐2 cm range. In extracting the LAI using the voxel‐based method, it is discovered that the appropriate voxel size is linearly dependent on the mean point spacing (y = 2.143x, R2= 0.826). This study provides useful guidance for monitoring the effectiveness of ecological conservation and restoration on the QTP. [ABSTRACT FROM AUTHOR]

Many studies have demonstrated that intrinsic self‐healing polyelectrolyte coatings can be fabricated by exponentially growing Layer‐by‐Layer (LbL) assembled polyelectrolyte multilayers. However, due to the lack of controlled self‐healing evaluation methods, the researches on self‐healing properties have remained at some simple qualitative characterization. In our study, a self‐healing branched polyethylenimine (bPEI)/poly(acrylic acid) (PAA) films is successfully prepared by LbL and a new systematical self‐healing evaluation method is developed. The cuts with controllable depth, width, and period can be easily fabricated on bPEI/PAA films through the colloidal lithography and photolithography. Colloidal lithography, as a facile, low‐cost, and versatile unconventional technique, can realize precise and repetitive fabrication of cuts at the same sample and in the same area, which will be beneficial to the systematic study and evaluate self‐healing behavior. The self‐healing behaviors on the different cuts are observed by scanning electron microscope (SEM). The SEM results reveal that bPEI/PAA film could realize damage/healing process for multiple times at the same sample and in the same area. In addition, the self‐healing abilities of the LbL films are related to the damage number, depth, and width of cuts. With the increase of damage number, depth, and width of cuts, the loss of polyelectrolyte was also increased, which lead to the flow of remaining polyelectrolytes were not enough to heal the cuts. This work provides a new route to systematically characterize the self‐healing ability of bPEI/PAA films as well as other polyelectrolyte films. [ABSTRACT FROM AUTHOR]

Purpose: To demonstrate the feasibility of 129Xe MR in evaluating the pulmonary physiological changes caused by PM2.5 in animal models. Methods: Six rats were treated with PM2.5 solution (16.2 mg/kg) by intratracheal instillation twice a week for 4 weeks, and another six rats treated with normal saline served as the control cohort. Pulmonary function tests, hyperpolarized 129Xe multi‐b diffusion‐weighted imaging, and chemical shift saturation recovery MR spectroscopy were performed on all rats, and the pulmonary structure and functional parameters were obtained from hyperpolarized 129Xe MR data. Additionally, histological analysis was performed on all rats to evaluate alveolar septal thickness. Statistical analysis of all the obtained parameters was performed using unpaired 2‐tailed t tests. Results: Compared with the control group, the measured exchange time constant increased from 11.74 ± 2.39 to 14.00 ± 2.84 ms (P <.05), and the septal wall thickness increased from 6.17 ± 0.48 to 6.74 ± 0.52 μm (P <.05) in the PM2.5 cohort by 129Xe MR spectroscopy, which correlated well with that obtained using quantitative histology (increased from 5.52 ± 0.32 to 6.20 ± 0.36 μm). Additionally, the mean TP/GAS ratio increased from 0.828 ± 0.115 to 1.019 ± 0.140 in the PM2.5 cohort (P =.021). Conclusions: Hyperpolarized 129Xe MR could quantify the changes in gas exchange physiology caused by PM2.5, indicating that the technique has the potential to be a useful tool for evaluation of pulmonary injury caused by air pollution in the future. [ABSTRACT FROM AUTHOR]

Monitoring fluctuations in enzyme overexpression facilitates early tumor detection and excision. An AIEgen probe (DQM‐ALP) for the imaging of alkaline phosphatase (ALP) activity was synthesized. The probe consists of a quinoline‐malononitrile (QM) core decorated with hydrophilic phosphate groups as ALP‐recognition units. The rapid liberation of DQM‐OH aggregates in the presence of ALP resulted in aggregation‐induced fluorescence. The up‐regulation of ALP expression in tumor cells was imaged using DQM‐ALP. The probe permeated into 3D cervical and liver tumor spheroids for imaging spatially heterogeneous ALP activity with high spatial resolution on a two‐photon microscopy platform, providing the fluorescence‐guided recognition of sub‐millimeter tumorigenesis. DQM‐ALP enabled differentiation between tumor and normal tissue ex vivo and in vivo, suggesting that the probe may serve as a powerful tool to assist surgeons during tumor resection. [ABSTRACT FROM AUTHOR]

High dielectric constant is highly desirable in capacitors and memory devices. In this work, oleic acid (OA)‐capped BaTiO3 nanocrystals were synthesized by a two‐phase approach. Polyimide (PI)/BaTiO3‐nanocrystal composite thin films with high dielectric constant have been successfully fabricated. The morphologies and dielectric properties of the hybrid films were exploited. The results showed that BaTiO3 nanocrystals can be uniformly dispersed in the PI thin films owing to the surface modification of OA‐capped BaTiO3 nanocrystals. It was found that the dielectric constant of composite film varies with the volume fraction of BaTiO3 nanocrystals and sintering temperatures and reaches a maximum value of 44.1, which is around 13 times higher than that of pristine PI thin film (3.2). These results demonstrated that PI/BaTiO3‐nanocrystal composite films have considerable application potential in microelectronic fields. [ABSTRACT FROM AUTHOR]

Purpose: To fast and accurately reconstruct human lung gas MRI from highly undersampled k‐space using deep learning. Methods: The scheme was comprised of coarse‐to‐fine nets (C‐net and F‐net). Zero‐filling images from retrospectively undersampled k‐space at an acceleration factor of 4 were used as input for C‐net, and then output intermediate results which were fed into F‐net. During training, a L2 loss function was adopted in C‐net, while a function that united L2 loss with proton prior knowledge was used in F‐net. The 871 hyperpolarized 129Xe pulmonary ventilation images from 72 volunteers were randomly arranged as training (90%) and testing (10%) data. Ventilation defect percentage comparisons were implemented using a paired 2‐tailed Student's t‐test and correlation analysis. Furthermore, prospective acquisitions were demonstrated in 5 healthy subjects and 5 asymptomatic smokers. Results: Each image with size of 96 × 84 could be reconstructed within 31 ms (mean absolute error was 4.35% and structural similarity was 0.7558). Compared with conventional compressed sensing MRI, the mean absolute error decreased by 17.92%, but the structural similarity increased by 6.33%. For ventilation defect percentage, there were no significant differences between the fully sampled and reconstructed images through the proposed algorithm (P = 0.932), but had significant correlations (r = 0.975; P < 0.001). The prospectively undersampled results validated a good agreement with fully sampled images, with no significant differences in ventilation defect percentage but significantly higher signal‐to‐noise ratio values. Conclusion: The proposed algorithm outperformed classical undersampling methods, paving the way for future use of deep learning in real‐time and accurate reconstruction of gas MRI. [ABSTRACT FROM AUTHOR]

A novel marine origin Bacillus subtilis strain H1 isolated from a shrimp culture pond effectively removed NH4+‐N, NO2-‐N and NO3-‐N, with a maximum ammonium, nitrite and nitrate removal rate of 2.35 mg NH4+‐N L−1 hr−1 per OD, 9.64 mg NO2-‐N L−1 hr−1 per OD and 0.75 mg NO3-‐N L−1 hr−1 respectively. The gas chromatography–isotope ratio mass spectrometry results indicated that N2O was emitted when 15NH4Cl, Na15NO2 or Na15NO3 was used. Additionally, N2 was also produced when Na15NO2 was used. Single‐factor experiments suggested that the optimal conditions for NH4+‐N and NO2-‐N removal were glucose as a carbon source, C/N 15, initial pH 7.5, 30 g/L NaCl, 28°C and a shaking speed of 160 rpm. Orthogonal tests showed that the optimal conditions for NH4+‐N removal were C/N 15, pH 9, 10 g/L NaCl and shaking speed 160 rpm when ammonium chloride was used as the substrate. The optimal conditions for NO2-‐N removal were C/N 10, pH 6, 10 g/L NaCl and a shaking speed of 160 rpm when sodium nitrite was used as the substrate. In summary, B. subtilis strain H1 had highly efficient aerobic nitrifying–denitrifying ability and high adaptability, suggesting that it is potentially valuable to marine aquaculture. [ABSTRACT FROM AUTHOR]

We investigated the magnetic and ferroelectric properties of orthochromite SmCrO3 by using density functional theory simulations. The atom coordinates of both Pbnm and Pna21 were calculated, and Pna21 was found to be the ground state structure. The spontaneous polarization in Pna21 structure is sensitive to delicate structure change which is induced by different antiferromagnetic order, and its direction is along the c axis. The spin structure of Pbnm was analyzed and it was found to not support ferroelectricity. The results revealed the origin of ferroelectricity of multiferroic SmCrO3 and explained the magnetoelectric effect. [ABSTRACT FROM AUTHOR]

Abstract: The reaction between a Ni−Y2O3‐stabilized ZrO2 (Ni‐YSZ) cermet anode and La5.4WO12−δ (LW) during cell fabrication is utilized to reduce carbon deposition in solid oxide fuel cells operated on methane fuel. The effect of the phase reactions on the microstructure, electrical conductivity, chemical interactions, and coking resistance of the anodes are systematically investigated. NixWy and La‐doped YSZ are formed by phase reactions and the synergistic effect between them increases the coking resistance dramatically. 2 wt % is demonstrated to be the optimal amount of LW to modify Ni‐YSZ to achieve best coking resistance. The cell with Ni‐YSZ‐2 wt % LW anode demonstrates a superior peak power density of 943 mW cm−2 at 800 °C with humidified methane as fuel, which is 10 % higher than that of Ni‐YSZ (859 mW cm−2). Furthermore, the cell is stable for 200 h in methane fuel with no clear performance degradation while the cell with unmodified anode fails after 0.5 h's operation. In summary, we provide a new way to rationally design Ni‐based cermet anode with high electrocatalytic activity and excellent coking resistance. [ABSTRACT FROM AUTHOR]

Hyperpolarized 129Xe gas MR has been a powerful tool for evaluating pulmonary structure and function due to the extremely high enhancement in spin polarization, the good solubility in the pulmonary parenchyma, and the excellent chemical sensitivity to its surrounding environment. Generally, the quantitative structural and functional information of the lung are evaluated using hyperpolarized 129Xe by employing the techniques of chemical shift saturation recovery (CSSR) and xenon polarization transfer contrast (XTC). Hyperpolarized 129Xe chemical exchange saturation transfer (Hyper‐CEST) is another method for quantifying the exchange information of hyperpolarized 129Xe by using the exchange of xenon signals according to its different chemical shifts, and it has been widely used in biosensor studies in vitro. However, the feasibility of using hyperpolarized 129Xe CEST to quantify the pulmonary gas exchange function in vivo is still unclear. In this study, the technique of CEST was used to quantitatively evaluate the gas exchange in the lung globally and regionally via hyperpolarized 129Xe MRS and MRI, respectively. A new parameter, the pulmonary apparent gas exchange time constant (Tapp), was defined, and it increased from 0.63 s to 0.95 s in chronic obstructive pulmonary disease (COPD) rats (induced by cigarette smoke and lipopolysaccharide exposure) versus the controls with a significant difference (P = 0.001). Additionally, the spatial distribution maps of Tapp in COPD rats' pulmonary parenchyma showed a regionally obvious increase compared with healthy rats. These results indicated that hyperpolarized 129Xe CEST MR was an effective method for globally and regionally quantifying the pulmonary gas exchange function, which would be helpful in diagnosing lung diseases that are related to gas exchange, such as COPD. [ABSTRACT FROM AUTHOR]

During the measurement of hyperpolarized 129Xe magnetic resonance imaging (MRI), the diffusion-weighted imaging (DWI) technique provides valuable information for the assessment of lung morphometry at the alveolar level, whereas the chemical shift saturation recovery (CSSR) technique can evaluate the gas exchange function of the lungs. To date, the two techniques have only been performed during separate breaths. However, the request for multiple breaths increases the cost and scanning time, limiting clinical application. Moreover, acquisition during separate breath-holds will increase the measurement error, because of the inconsistent physiological status of the lungs. Here, we present a new method, referred to as diffusion-weighted chemical shift saturation recovery (DWCSSR), in order to perform both DWI and CSSR within a single breath-hold. Compared with sequential single-breath schemes (namely the 'CSSR + DWI' scheme and the 'DWI + CSSR' scheme), the DWCSSR scheme is able to significantly shorten the breath-hold time, as well as to obtain high signal-to-noise ratio (SNR) signals in both DWI and CSSR data. This scheme enables comprehensive information on lung morphometry and function to be obtained within a single breath-hold. In vivo experimental results demonstrate that DWCSSR has great potential for the evaluation and diagnosis of pulmonary diseases. [ABSTRACT FROM AUTHOR]

The electrochemistry and annihilation electrochemiluminescence (ECL) of a series of chiral cationic helicene luminophores containing various substituents were investigated in acetonitrile solvent. The electrochemical characterization evidenced a systematic reversible reduction of cationic derivatives, whereas the oxidation could be reversible or not, depending on the nature of the core heteroatoms within the structure as well as the functional-group appendages. One of the key parameters governing the ECL intensity is, indeed, the formal redox potentials for the electrogeneration of the neutral radical and dication radical species, which will undergo the annihilation reaction. On that basis, a thermodynamic wall of efficiency was proposed in the case of ECL annihilation pathway to predict the formation efficiency of the emitting excited state and, eventually, the light emission's strength. This very simple wall is constructed by plotting the difference of formal potentials in function of the fluorescence wavelength, thus delimiting two domains where ECL is thermodynamically possible or unfavorable. [ABSTRACT FROM AUTHOR]

The physicochemical properties of cationic dioxa ( 1), azaoxa ( 2), and diaza ( 3) [6]helicenes demonstrate a much higher chemical stability of the diaza adduct 3 (p KR +=20.4 [ABSTRACT FROM AUTHOR]

The phenomenon of electrochemiluminescence (ECL) is luminescence triggered by electrochemical reactions at electrodes. Heterogeneous electron transfers are deeply dependent on electrode materials, therefore, besides the usual parameters, the right choice of the electrode is a crucial point to address properly in order to maximize the emission efficiency. Many different electrodes have been studied, from metallic platinum or gold through transparent indium-doped tin oxide to carbon-based electrodes, and others, such as paper-based and boron-doped diamond. This review summarizes results of ECL at different electrode surfaces, disclosing the relative advantages and disadvantages, with a particular attention to the reference Ru(bpy)32+/TPrA coreactant system. In other words, we offer an insight to recognize and select the optimal electrode material for the ECL systems of interest with particular emphasis on the biosensing applications. [ABSTRACT FROM AUTHOR]