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Photosynthesis is a process that uses solar energy to fix CO2 in the air and converts it into sugar, and ultimately powers almost all life activities on the earth. C3 photosynthesis is the most common form of photosynthesis in crops. Current efforts of increasing crop yields in response to growing global food requirement are mostly focused on improving C3 photosynthesis. In this review, we summarized the strategies of C3 photosynthesis improvement in terms of Rubisco properties and photorespiratory limitation. Potential engineered targets include Rubisco subunits and their catalytic sites, Rubisco assembly chaperones, and Rubisco activase. In addition, we reviewed multiple photorespiratory bypasses built by strategies of synthetic biology to reduce the release of CO2 and ammonia and minimize energy consumption by photorespiration. The potential strategies are suggested to enhance C3 photosynthesis and boost crop production.

The collective oscillation of free electrons at the nanoscale surface of gold nanostructures is closely modulated by tuning the size, shape/morphology, phase, composition, hybridization, assembly, and nanopatterning, along with the surroundings of the plasmonic surface located at a dielectric interface with air, liquid, and solid. This review first introduces the physical origin of the intrinsic optical properties of gold nanostructures and further summarizes stimuli-responsive changes in optical properties, metal-field-enhanced optical signals, luminescence spectral shaping, chiroptical response, and photogenerated hot carriers. The current success in the landscape of nanoscience and nanotechnology mainly originates from the abundant optical properties of gold nanostructures in the thermodynamically stable face-centered cubic (fcc) phase. It has been further extended by crystal phase engineering to prepare thermodynamically unfavorable phases (e.g., kinetically stable) and heterophases to modulate their intriguing phase-dependent optical properties. A broad range of promising applications, including but not limited to full-color displays, solar energy harvesting, photochemical reactions, optical sensing, and microscopic/biomedical imaging, have fostered parallel research on the multitude of physical effects occurring in gold nanostructures. This article is protected by copyright. All rights reserved.

The translocation of photosynthate carbohydrates, such as sucrose, is critical for plant growth and crop yield. Previous studies have revealed that sugar transporters, plasmodesmata and sieve plates act as important controllers in sucrose loading into and unloading from phloem in the vascular system. However, other pivotal steps for the regulation of sucrose movement remain largely elusive. In this study, characterization of two starch excesses in mesophyll (sem) mutants and dye and sucrose export assays were performed to provide insights into the regulatory networks that drive source-sink relations in rice. Map-based cloning identified two allelic mutations in a gene encoding a GLUCAN SYNTHASE-LIKE (GSL) protein, thus indicating a role for SEM1 in callose biosynthesis. Subcellular localization in rice showed that SEM1 localized to the plasma membrane. In situ expression analysis and GUS staining showed that SEM1 was mainly expressed in vascular phloem cells. Reduced sucrose transport was found in the sem1-1/1-2 mutant, which led to excessive starch accumulation in source leaves and inhibited photosynthesis. Paraffin section and transmission electron microscopy experiments revealed that less-developed vascular cells (VCs) in sem1-1/1-2 potentially disturbed sugar movement. Moreover, dye and sugar trafficking experiments revealed that aberrant VC development was the main reason for the pleiotropic phenotype of sem1-1/1-2. In total, efficient sucrose loading into the phloem benefits from an optional number of VCs with a large vacuole that could act as a buffer holding tank for sucrose passing from the vascular bundle sheath.

Previous functional magnetic resonance imaging (fMRI) studies have shown that brain responses to nociceptive pain, non‐nociceptive somatosensory, visual, and auditory stimuli are extremely similar. Actually, perception of external sensory stimulation requires complex interactions among distributed cortical and subcortical brain regions. However, the interactions among these regions elicited by nociceptive pain remain unclear, which limits our understanding of mechanisms of pain from a brain network perspective. Task fMRI data were collected with a random sequence of intermixed stimuli of four sensory modalities in 80 healthy subjects. Whole‐brain psychophysiological interaction analysis was performed to identify task‐modulated functional connectivity (FC) patterns for each modality. Task‐modulated FC strength and graph‐theoretical‐based network properties were compared among the four modalities. Lastly, we performed across‐sensory‐modality prediction analysis based on the whole‐brain task‐modulated FC patterns to confirm the specific relationship between brain patterns and sensory modalities. For each sensory modality, task‐modulated FC patterns were distributed over widespread brain regions beyond those typically activated or deactivated during the stimulation. As compared with the other three sensory modalities, nociceptive stimulation exhibited significantly different patterns (more widespread and stronger FC within the cingulo‐opercular network, between cingulo‐opercular and sensorimotor networks, between cingulo‐opercular and emotional networks, and between default mode and emotional networks) and global property (smaller modularity). Further, a cross‐sensory‐modality prediction analysis found that task‐modulated FC patterns could predict sensory modality at the subject level successfully. Collectively, these results demonstrated that the whole‐brain task‐modulated FC is preferentially modulated by pain, thus providing new insights into the neural mechanisms of pain processing., This study aimed to reveal whether nociceptive pain could elicit different task‐modulated functional connectivity (FC) patterns from other sensory modalities (non‐nociceptive somatosensory, visual, and auditory). According to the results, nociceptive stimulation exhibited significantly different regional and global task‐modulated FC features from those of the other three sensory modalities, and the task‐modulated FC patterns were predictive of sensory modality at the subject level. These results could provide new insights from the perceptive of task‐modulated brain network into the neural mechanisms of pain processing.

Hydrogen-bonded organic frameworks (HOFs) have emerged as rapidly growing porous materials while established permanent porosities are very fragile and difficult to stabilize due to weak hydrogen-bonding interactions among building units. Herein, we report a stable hydrogen-bonded metallotecton framework (termed as HOF-ZJU-102) that was constructed through hydrogen-bonding networks between cationic metal-organic complexes [Cu2 (Hade)4 (H2 O)2 ]4+ (Hade=adenine) and GeF62- anions. The framework not only shows permanent porosity, but also exhibits efficient separation performance of C2 H2 /C2 H4 at room temperature. More interestingly, its crystal structure could be irreversibly transformed into isostructural counterpart HOF-ZJU-101 by ion exchange in the SiF62- containing solution, evidenced by multiple characterization techniques including gas sorption measurements, 19 F NMR spectra, FTIR and EDS. Utilizing such an ion exchange mechanism, the collapsed HOF-ZJU-102 could be restored into HOF-ZJU-101 by simply soaking in the salt solution.

The detection of Singlet oxygen (1O2) is of great interest to develop cancer therapies, because it can initiate a plethora of events that result in cell death. Singlet oxygen sensor green (SOSG) is considered the preferred probe because of its claimed high selectivity to Singlet oxygen (1O2). Although many researchers have used SOSG to detect 1O2 generation in Sonodynamic therapy (SDT) processes, the effect of ultrasound irradiation on SOSG has not been comprehensively evaluated. In this study, we conducted systematic experiments to determine SOSG activation in the presence of ultrasound irradiation. We found that the SOSG exhibited the abnormal physicochemical phenomena in distilled water in the presence of ultrasound. The fluorescence intensity of SOSG increased significantly when exposed to ultrasound alone. The results showed that there was a linear positive correlation between the treatment duration of different ultrasound intensities or SOSG concentrations and the fluorescence intensity of SOSG, respectively. In addition, scavenger tests also indicated that hydroxyl radicals (•OH) might be involved in the activation of SOSG. In conclusion, our results suggest that the influences of experimental conditions to SOSG must be fully considered, and that SOSG may not be a suitable probe for 1O2 in SDT.

The heterogeneity in biofilms is a major challenge in biofilm therapies due to different susceptibility of bacteria and extracellular polymeric substances (EPS) to antibacterial agents. Here, we describe a therapeutic strategy that overcame biofilm heterogeneity, where antibacterial agent (NO) and EPS dispersant (reactive oxygen species (ROS)-inducing Fe

Separation of Xe and Kr is one of the greatest challenges in the gas industries owing to their close molecular structure and similar properties. Energy-effective adsorption-based separation using chemically stable carbon adsorbents is a promising technology. We propose a strategy for Xe/Kr separation using MOF-derived metallic carbon adsorbents. M-Gallate (M=Ni, Co) were used as precursors to fabricate CoNi alloy nanoparticles embedded carbon adsorbents by one-step auto-reduction pyrolysis. The optimal NiCo@C-700 exhibits record-high IAST selectivity (24.1) and Henry's selectivity (20.1) of Xe/Kr among reported carbon adsorbents. DFT calculations, local density of states calculation, charge density difference, and Bader charge analysis reveal the great affinity with Xe benefits from the presence of Ni or CoNi nanoparticles as a result of more charge transfer from Xe than Kr to metal, thus providing higher binding energy. Breakthrough experiments further verify NiCo@C-700 a promising candidate for Xe/Kr separation.

LRWD1, also known as ORCA, is a nuclear protein functioning in multiple biological processes. Using its WD40 domain LRWD1 interacts with repressive histone marks and maintains the silencing of heterochromatin regions in mammalian cells. ORCA also associates with the origin recognition complex (ORC) and facilitates prereplication complex formation at late-replicating origins. However, whether LRWD1 plays a role during development and the functional significance of LRWD1 in vivo remains largely unknown. Using gene-trap approach we generated Lrwd1 knockout mice and examined the expression of Lrwd1 during embryonic development. We found that Lrwd1 is ubiquitously expressed in the majority of the developing mouse embryo. Depletion of LRWD1 did not affect embryonic development but the postnatal growth of the homozygous mutants is retarded. In vitro cultured mouse embryonic fibroblasts (MEFs) depleted of LRWD1 displayed a reduced proliferation compared to wild type cells. We also showed that the knockout of Lrwd1 in MEFs increased the expression of the epigenetically silenced repetitive elements but with minimal effect on the expression of protein coding genes. Together, these results suggest that LRWD1 plays an important, but not essential, role in postnatal development by regulating cell proliferation likely through modulating DNA replication.

Background During the early stages of the pandemic, some coronavirus disease (COVID‐19)patients were misdiagnosed as having influenza, which aroused the concern that some deaths attributed to influenza were actually COVID‐19‐related. Howerver, little is known about whether coinfection with influenza contributes to severity of COVID‐19 pneumonia, and the optimal therapeutic strategy for these patients. Methods We retrospectively studied 128 hospitalized patients with COVID‐19 pneumonia. All patients were positive severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2)positive by nucleic acid detection. 64 cases were co‐infected with influenza A/B and the other 64 were influenza negative, matched by age, sex, and days from onset of symptoms. Results Among the 64 co‐infected patients, 54 (84.4%) were co‐infected with influenza A, and 10 (15.6%) with influenza B. The median duration of viral shedding time from admission was longer for patients with influenza coinfection (17.0 days) than for those without influenza coinfection (12.0 days) (P

The morphology of bulliform cells located on the upper epidermis of leaves is one of the most important cell structures affecting leaf shape. Although many mechanisms regulating the development of bulliform cells have been reported, the fine regulatory mechanisms governing this process have rarely been described. To identify novel components regulating rice leaf morphology, a mutant showing a constitutively rolling phenotype from the seedling stage to flowering, known as crm1‐D, was selected for further analysis. Anatomical analyses in crm1‐D were attributable to the size reduction of bulliform cells. The crm1‐D was controlled by a single dominant nuclear gene. Map‐based cloning revealed that Roc8, an HD zipper class IV family member, was responsible for the crm1‐D phenotype. Notably, the 50‐bp sequence in the 3′‐untranslated region (3′‐UTR) of the Roc8 gene represses Roc8 at the translational level. Moreover, the roc8 knockdown lines notably increased the size of bulliform cells. A series of assays revealed that Roc8 negatively regulates the size of bulliform cells. Unexpectedly, Roc8 was also observed to positively mediate lignin biosynthesis without incurring a production penalty. The above results show that Roc8 may have a practical application in cultivating materials with high photosynthetic efficiency and low lignin content.

Adsorptive separation of xenon (Xe) and krypton (Kr) is a promising technique but remains a daunting challenge since they are atomic gases without dipole or quadruple moments. Herein we report a strategy for fabricating angular anion-pillared materials featuring shell-like Xe nano-traps, which provide a cooperative effect conferred by the pore confinement and multiple specific interactions. The perfect permanent pore channel (4-5 Å) of Ni(4-DPDS)

Xe/Kr separation is an industrially important but challenging process owing to their inert properties and low concentrations in the air. Energy-effective adsorption-based separation is a promising technology. Herein, two isostructural hydrogen-bonded metal-nucleobase frameworks (HOF-ZJU-201 and HOF-ZJU-202) are capable of separating Xe/Kr under ambient conditions and strike an excellent balance between capacity and selectivity. The Xe capacity of HOF-ZJU-201a reaches 3.01 mmol g

There is growing interest in developing triplet photosensitizers in terms of implementing photochemical strategies in synthetic chemistry. However, synthesis of stable triplet organic photosensitizers is nontrivial and often requires the use of heavy atoms. Herein, an alternative strategy is demonstrated to enhance the triplet generation efficiency by implanting lone‐pair donor–acceptor bonds in the conjugated covalent organic frameworks (COFs). This powerful method is validated using COFs that host triazine, a moiety that has been extensively investigated in photocatalysis. Spectroscopic analysis and theoretical calculations reveal substantial improvements in the photoabsorptivity and triple‐state photogeneration efficiency, consistent with catalytic tests concerning industrially relevant sulfide oxidation. These systems represent a promising addition to the rapidly increasing arsenal of synthetic photocatalytic systems., Stable organic triplet photosensitizers are developed by incorporating the oxidated triazine moiety into conjugated covalent organic frameworks. Greatly improved intersystem crossing processes and triplet generation efficiency are observed after anchoring oxygen atoms at the N ends in triazine, steering the photocatalysis toward the energy transfer pathway.

This paper mainly focuses on the optimal control and stabilization for networked control systems with packet dropout, measurement delay and input delay. The main contributions are two‐fold...

Ischemic heart disease (IHD) is the most occurring cardiovascular-associated disease, which is a primary leading cause of cardiac disability and death worldwide. Myocardial ischemia/reperfusion injury (MI/RI) has been linked to IHD-induced cardiomyocytes apoptosis and tissue damage. The clinical studies have indicated that pathophysiologic mechanisms of MI/RI are associated with reactive oxygen species generation, calcium overload, energy metabolism disorder, neutrophil infiltration, and others. However, the genetic mechanism of MI/RI remains unclear. In this study, we successfully established the reproducing abnormal heart observed in rat, of IHD-induced MI/RI post operation. By using these rats, we illustrated that expression of miR-181b-5p was increased not only in both hypoxia/reoxygenation-cultured H9C2 but also heart of myocardial ischemia/reperfusion (MI/R) rat. Suppression of the miR-181b-5p cardiomyocytes apoptosis and rescued myocardial infarction. Additionally, our data indicated that miR-181b-5p negatively regulates the expression of AKT3 and PIK3R3 through directly binding with its 3'-untranslated region. More importantly, suppression of miR-181b-5p protects the cardiomyocytes apoptosis and tissue damage from MI/R via regulation of PIK3R3 and AKT3. Hence, our study indicates that miR-181b-5p is essential for MI/RI via regulation of PI3K/Akt signaling pathway and could be a potential therapeutic target in IHD.

DNA replication stress threatens ordinary DNA synthesis. The evolutionarily conserved DNA replication stress response pathway involves sensor kinase Mec1/ATR, adaptor protein Mrc1/Claspin, and effector kinase Rad53/Chk1, which spurs a host of changes to stabilize replication forks and maintain genome integrity. DNA replication forks consist of largely distinct sets of proteins at leading and lagging strands that function autonomously in DNA synthesis in vitro. In this article, we discuss eSPAN and BrdU-IP-ssSeq, strand-specific sequencing technologies that permit analysis of protein localization and DNA synthesis at individual strands in budding yeast. Using these approaches, we show that under replication stress Rad53 stalls DNA synthesis on both leading and lagging strands. On lagging strands, it stimulates PCNA unloading, and on leading strands, it attenuates the replication function of Mrc1-Tof1. We propose that in doing so, Rad53 couples leading and lagging strand DNA synthesis during replication stress, thereby preventing the emergence of harmful ssDNA.

Intraplaque hemorrhage (IPH) plays a major role in the aggressive progression of vulnerable plaque, leading to acute cardiovascular events. We previously demonstrated that sonodynamic therapy (SDT) inhibits atherosclerotic plaque progression. In this study, we investigated whether SDT could also be applied to treat more advanced hemorrhagic plaque and addressed the underlying mechanism. SDT decreased atherosclerotic burden, positively altered atherosclerotic lesion composition, and alleviated iron retention in rabbit hemorrhagic plaques. Furthermore, SDT reduced iron retention by stimulating ferroportin 1 (Fpn1) expression in apolipoprotein E (ApoE)−/− mouse plaques with high susceptibility to IPH. Subsequently, SDT inhibited iron‐overload‐induced foam‐cell formation and pro‐inflammatory cytokines secretion in vitro. Moreover, SDT reduced levels of the labile iron pool and ferritin expression via the reactive oxygen species (ROS)‐nuclear factor erythroid 2‐related factor 2 (Nrf2)‐FPN1 pathway. SDT exerted therapeutic effects on hemorrhagic plaques and reduced iron retention via the ROS‐Nrf2‐FPN1 pathway in macrophages, thereby suggesting that it is a potential translational strategy for patients with advanced atherosclerosis in clinical practice.

Cryopreservation causes cryoinjury to oocytes and impairs their developmental competence. Melatonin (MLT) can improve the effect of cryopreservation in animal oocytes. However, no such studies on human oocytes have been reported. In this study, collected in vitro-matured human oocytes were randomly divided into the following groups: fresh group, MLT-treated cryopreservation (MC) group, and no-MLT-treated cryopreservation (NC) group. After vitrification and warming, viable oocytes from these three groups were assessed for their mitochondrial function, ultrastructure, permeability of oolemma, early apoptosis, developmental competence, and cryotolerance-related gene expression. First, fluorescence staining results revealed that oocytes from the 10-9 M subgroup showed the lowest intracellular reactive oxygen species and Ca2+ levels and highest mitochondrial membrane potential among the MC subgroups (10-11 , 10-9 , 10-7 , and 10-5 M). In subsequent experiments, oocytes from the 10-9 M-MC group were observed to maintain the normal ultrastructural features and the permeability of the oolemma. Compared with those of the oocytes in the NC group, the early apoptosis rate significantly decreased (P