The Z-scheme has been proven to be an effective strategy to develop a high-efficiency visible-light photocatalyst. However, the visible-light-responding active component in the Z-scheme system is ...usually restricted to semiconductor materials sensitive to visible light. On the other hand, noble-metal nanoparticles (such as Ag) can act as an active component for the design of high-efficiency plasmonic photocatalysts due to their strong absorption in the visible light region. In this study, H2WO4·H2O/Ag/AgCl composite nanoplates were prepared by a one-step ionic reaction between Ag8W4O16/Ag nanorods and HCl aqueous solution. The photocatalytic activity experiments indicated that the H2WO4·H2O/Ag/AgCl composite nanoplates exhibited a much higher photocatalytic activity than the one-component (H2WO4·H2O) or two-component (such as Ag/AgCl and H2WO4·H2O/Ag) photocatalysts. On the basis of photocatalytic activity and band structure analysis, a plasmonic Z-scheme photocatalytic mechanism is proposed; namely, two-step visible-light absorption is caused by the localized surface plasmon resonance of metallic Ag nanoparticles and the band gap photoexcitation of H2WO4·H2O. The present results suggest that metallic Ag nanoparticles can act as an effective active component for the construction of a Z-scheme visible-light photocatalyst. Considering the versatility and flexibility of noble-metal nanoparticles and semiconductors, this work may provide some insight into the design of novel and highly efficient Z-scheme visible-light photocatalysts.
The superoxide dismutase 1 (SOD1) mutation is one of the most notable causes of amyotrophic lateral sclerosis (ALS), and modifying the mutant SOD1 gene is the best approach for the treatment of ...patients with ALS linked to the mutations in this gene. Clustered regularly interspaced short palindromic repeat (CRISPR)/CRISPR-associated (Cas9)/sgRNA delivered by the adeno-associated virus (AAV) system is a powerful tool for genome editing in the central nervous system (CNS). Here, we tested the capacity of the AAV-SaCas9-sgRNA system to modify mutant SOD1 in SOD1G93A transgenic mice and found that AAV9-SaCas9-sgRNA5 deleted the SOD1 gene, improved the lifespan of SOD1G93A mice by 54.6%, and notably ameliorated the performance of ALS transgenic mice. An immunochemical analysis showed that the expression of mutant SOD1 was very weak in motor neurons expressing SaCas9-sgRNA5. Consequently, the area showing muscle atrophy was more notably restored in the group treated with SaCas9-sgRNA5 compared with the group treated with SaCas9-sgLacZ. In addition, deep sequencing did not show the indel mutation in the gene highly matched to sgRNA5. Hence, AAV9-SaCas9-sgRNA-based gene editing is a feasible potential treatment for patients with ALS linked to SOD1 mutations.
A robotic assembly system for small components precision assembly is designed, which mainly comprises an industrial robot, three cameras, and a force sensor. The industrial robot is employed to ...conduct two classic assembly subtasks, i.e., grasping and pose alignment. An automatic grasping method with monocular vision guidance is proposed. The grasping strategy consists of three stages, i.e., aligning, approaching, and grasping, and picks up components with high efficiency. Moreover, a coordinated pose alignment strategy with two eye-to-hand microscopic cameras is developed. It can realize pose alignment efficiently and accurately. Besides, based on differential movement principle, the position offset due to the end-effector’s orientation adjustment is calculated and compensated, which avoids the grasped component out of the microscopic cameras’ field of view. Finally, a series of grasping and pose alignment experiments are conducted on designed robotic precision assembly system to verify the effectiveness of the proposed grasping and pose alignment methods. The grasping success rate is up to 100
%
with 30 times experiments, the orientation alignment error is less than 0.05
∘
, and the position alignment error is less than 26
μ
m.
In this paper, a multilayer ultra-wideband transparent metamaterial wave absorber is proposed, which has the characteristics of ultra-wideband wave absorption, light transmission and flexible ...bending; in addition, due to the complete symmetry of the structure, the absorber has polarization insensitivity to incident electromagnetic waves. Both simulation and experimental results show that the frequency range of the microwave absorption rate is higher than 90% between 8.7 GHz and 38.9 GHz (between which most of the absorption rate can reach more than 95%), the total bandwidth is 30.2 GHz, and the relative bandwidth is 126.9%, realizing microwave broadband absorption and covering commonly used communication frequency bands such as X-band, Ku-band, and K-band. A sample was processed and tested. The test results are in good agreement with the results of the theoretical analysis, which proves the correctness of the theoretical analysis. In addition, through the selection and oxidation of indium tin (ITO) materials, the metamaterial also has the characteristics of optical transparency and flexibility, so it has potential application value in the window radar stealth and conformal radar stealth of weapons and equipment.
An automatic precision robot assembly system is established. The robot assembly system mainly consists of an industrial robot, three cameras, a micro force sensor, and a specific gripper. The ...industrial robot is a six-axis serial manipulator, which is used to conduct grasping and assembly subtasks. Two microscopic cameras are fixed on two high accuracy translational platforms to provide visual information in aligning stage for assembly. While one conventional camera is installed on the robotic end effector to guide the gripper to grasp component. The micro force sensor is installed on the robotic end effector to perceive the contacted forces in inserting stage. According to the characteristics of components, an adsorptive gripper is designed to pick up components. In addition, a three-stage “aligning–approaching–grasping” control strategy for grasping subtask and a two-stage “aligning–inserting” control strategy for assembly subtask are proposed. Position offset compensation is computed and introduced into aligning stage for assembly to make the grasped component in the microscopic cameras’ small field of view. Finally, based on the established robot assembly system and the proposed control strategies, the assembly tasks including grasping and assembly are carried out automatically. With 30 grasping experiments, the success rate is 100%. Besides, the position and orientation alignment errors of pose alignment for assembly are less than 20 μm and 0.1°.
Petit Manseng is widely used for fermenting sweet wine and is popular among younger consumers because of its sweet taste and attractive flavor. To understand the mechanisms underlying spontaneous ...fermentation of Petit Manseng sweet wine in Xinjiang, the dynamic changes in the microbial population and volatile compounds were investigated through high-throughput sequencing (HTS) and headspace solid-phase microextraction (HS-SPME) coupled to gas chromatography-mass spectrometry (GC-MS) technology, respectively. Moreover, the relationship between the microbial population and volatile compounds was deduced
via
multivariate data analysis.
Candida
and
Mortierella
were dominant genera in Petit Manseng wine during spontaneous fermentation. Many fermentative aroma compounds, including ethyl octanoate, isoamyl acetate, ethyl butyrate, ethyl decanoate, isoamyl alcohol, ethyl laurate, isopropyl acetate, hexanoic acid, and octanoic acid, were noted and found to be responsible for the strong fruity and fatty aroma of Petit Manseng sweet wine. Multivariate data analysis indicated that the predominant microorganisms contributed to the formation of these fermentative aroma compounds.
Hannaella
and
Neomicrosphaeropsis
displayed a significantly positive correlation with the 6-methylhept-5-en-2-one produced. The current results provide a reference for producing Petit Manseng sweet wine with desirable characteristics.
Fibroblast growth factor 9 (FGF9) has long been assumed to modulate multiple biological processes, yet very little is known about the impact of FGF9 on neurodevelopment. Herein, we found that loss of ...Fgf9 in olig1 progenitor cells induced epilepsy in mice, with pathological changes in the cortex. Then depleting Fgf9 in different neural populations revealed that epilepsy was associated with GABAergic neurons. Fgf9 CKO in GABAergic neuron (CKO
) mice exhibited not only the most severe seizures, but also the most severe growth retardation and highest mortality. Fgf9 deletion in CKO
mice caused neuronal apoptosis and decreased GABA expression, leading to a GABA/Glu imbalance and epilepsy. The adenylate cyclase/cyclic AMP and ERK signaling pathways were activated in this process. Recombinant FGF9 proteoliposomes could significantly decrease the number of seizures. Furthermore, the decrease of FGF9 was commonly observed in serum of epileptic patients, especially those with focal seizures. Thus, FGF9 plays essential roles in GABAergic neuron survival and epilepsy pathology, which could serve as a new target for the treatment of epilepsy.
The circadian clock in plants synchronizes biological processes that display cyclic 24-h oscillation based on metabolic and physiological reactions. This clock is a precise timekeeping system, that ...helps anticipate diurnal changes; e.g., expression levels of clock-related genes move in synchrony with changes in pathogen infection and help prepare appropriate defense responses in advance. Salicylic acid (SA) is a plant hormone and immune signal involved in systemic acquired resistance (SAR)-mediated defense responses. SA signaling induces cellular redox changes, and degradation and rhythmic nuclear translocation of the non-expresser of
genes 1 (NPR1) protein. Recent studies demonstrate the ability of the circadian clock to predict various potential attackers, and of redox signaling to determine appropriate defense against pathogen infection. Interaction of the circadian clock with redox rhythm promotes the balance between immunity and growth. We review here a variety of recent evidence for the intricate relationship between circadian clock and plant immune response, with a focus on the roles of redox rhythm and NPR1 in the circadian clock and plant immunity.
Ectoine, an osmotic pressure-compensated solute, is used in the food, agriculture, medicine, and cosmetics industries due to its ability to protect macromolecules. In this study, an ectoine-producing ...variant of
, ET08, was genetically constructed by introducing the
gene cluster and eliminating metabolic pathways involving lysine and pyruvate. Medium optimization enhanced ectoine production from 1.87 to 10.2 g/L. Analysis of the transcriptional levels revealed that supplementation with ammonium sulfate enhanced the metabolic flux towards the biosynthesis of ectoine. Furthermore, by optimizing the copy number of
,
, and
, the recombinant
ET11 (
:
:
= 1:2:1) produced 12.9 g/L ectoine in the shake flask and 53.2 g/L ectoine in a fed-batch fermenter, representing the highest ectoine titer produced by
, which has great industrial prospects.
Cellulose is an economical, biodegradable, widely available, and eco-friendly natural macromolecule. But its utilization has been restricted due to its insolubility in water and common organic ...solvents. In this work, soluble fluorescent probes based on cellulose were synthesized. Firstly, the primary hydroxyl group in glucose units was reacted with SOCl2 to introduce Cl and obtain chloro-cellulose (Cell-Cl). This operation breaks down the regular structure and hydrogen bonding of the original cellulose, enabling it to dissolve in DMSO. Secondly, the Cell-Cl reacted with CS2 and 2-mercaptobenzothiazole to obtain a cellulose-based macromolecular RAFT reagent (Cell-CTA). Finally, the fluorescent monomers which bears -C=C- and naphthalimide, and methacrylic acid (MAA) were grafted onto the main chain of cellulose through RAFT polymerization. Thus, cellulose-based readily soluble macromolecular fluorescent probes were obtained. The cellulose-based probes can specifically recognize Fe3+ in pure water and can be recycled and regenerated. Additionally, the cellulose-based probes exhibit remarkable adsorption and separation properties for Fe3+ ions. The modification of cellulose decreases its crystallinity and introduces hydrophilic groups and fluorophores, which enables cellulose to be soluble in both pure water and the organic solvent DMSO. This work expands the application range of cellulose-based copolymers.
•Cellulose could be modified in common organic solvents throughout the entire process.•Cellulose-based macromolecular fluorescent probes can be dissolved in both pure water and t DMSO.•Cellulose-based probes can selectively identify Fe3+ in pure water, it also can adsorb and separate Fe3+.•Cellulose based RAFT reagent could further expanded the application range of cellulose.
PDF
