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Passivation of organic iodides without annealing induces the formation of iodine interstitial (Ii) defects. The cations of organic iodides with appropriate structures can suppress Ii migration, leading to a device efficiency of 24.20% and enhanced operational stability.

We present a nickel-catalyzed divergent formylation and carboxylation reaction of aryl halides with isocyanides, affording aldehydes and carboxylic acids, respectively.

DESs can swell and sulfate cellulose, greatly reduce the production energy consumption of CNF, and successfully used CNF in food packaging film.

Layered graphene and molybdenum disulfide have outstanding sodium ion storage properties that make them suitable for sodium-ion batteries (SIBs).

Helmholtz resonators are widely applied in industries to reduce the transmission of unwanted noise and passively attenuate tonal noise in pipes/ducts. For example, internal combustion engines take advantage of Helmholtz resonators by combining air box, subwoofers and perforated pipes/plates to reduce engine noise emission nowadays. However, the main drawback of the conventional Helmholtz resonators includes a very narrow bandwidth. To broaden the effective noise damping frequency range of Helmholtz resonators, a number of different improved designs are reported and tested recently in the literature such as applying an array of separated resonators or implementing mechanical-coupled Helmholtz resonators. In this work, we conduct a brief review on the aeroacoustics damping performance of coupled Helmholtz resonators over low frequency range. The noise damping performances could be characterized and quantified in terms of transmission loss and sound absorption coefficient. Both definitions are discussed. Comparison is then made between the separately working resonators and the mechanical-coupled ones. This is achieved by replacing the sharable flexible sidewall with a rigid sidewall. The effect of the mean grazing flow is also discussed and examined on the noise damping performances. An experimental case study of the present authors is included. Additionally, to improve the noise damping performance further, an overview of the resonators neck with different noise damping materials inserted is conducted. Finally, 3D numerical approaches in simulating the aeroacoustics damping performances of coupled Helmholtz resonators are reviewed. This case study and brief overview provides a guidance on improving the design of coupled Helmholtz resonators and an array of Helmholtz resonators.

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.

Aiming at the problem that there is a strong eardrum pressure in the passenger car during the closing process, two analysis and prediction methods, fast formula prediction and CFD simulation based on accurate models, are proposed. The regression model of ear pressure comfort was established by DOE method and multiple linear regression; The simulation software star-CCM+ is applied to simulate and analyze the dynamic characteristics of the flow field in the cockpit during the closing process by using the overlapping grid technology, and the pressure change curve near the ear is obtained. Finally, the CFD numerical simulation model is established by comparing and analyzing the regression prediction analysis results and the real vehicle test data. The results show that the effects of closing speed, effective opening area of pressure relief valve and air tightness of the whole vehicle on the pressure of passengers’ eardrums decrease in turn, and the prediction error of multiple linear regression equation is 17 %; The analysis error of the internal flow field dynamic characteristic model based on refined modeling is 8 %. This study provides a theoretical basis for solving the problem of rapid prediction of eardrum pressure and optimization of engineering structure.

Brown adipocyte maturation during postnatal development is essential for brown adipose tissue (BAT) to protect animals against cold. Impaired maturation of brown adipocytes leads to cold intolerance. However, the molecular mechanisms that determine the maturation of brown adipocytes during postnatal development are not fully understood. Here, we identify Wilms’ tumor 1-associating protein (WTAP) as an essential regulator in the postnatal development and maturation of BAT. BAT-specific knockout of Wtap (Wtap-BKO) severely impairs maturation of BAT in vivo by decreasing the expression of BAT-selective genes, leading to the whitening of interscapular BAT (iBAT). Single nucleus RNA-sequencing analysis shows the dynamic changes of cell heterogeneity in iBAT of Wtap-BKO mice. Adult mice with WTAP deficiency in BAT display hypothermic and succumb to acute cold challenge. Mechanistically, WTAP deficiency decreases m6A mRNA modification by reducing the protein stability of METTL3. BAT-specific overexpression of Mettl3 partially rescues the phenotypes observed in Wtap-BKO mice. These data demonstrate that WTAP/METTL3 plays an essential role in iBAT postnatal development and thermogenesis.

Di-(2-ethylhexyl) phthalate (DEHP) is one of the most used plasticizers which have contaminated environment widely, and its extensive use causes female reproductive injury. Melatonin has a substantial protective effect against female reproductive toxicity. This study was undertaken to investigate the influence of melatonin on DEHP-induced damage of human granulosa cells (GCs) in vitro and explore the potential mechanisms. Here, we found that melatonin treatment alleviated DEHP-induced human GCs apoptosis and improved mitochondrial function via inhibiting dynamin-related protein 1 (Drp1) mediated mitochondrial fission. Melatonin inhibited the expression, activation and oligomerization of Drp1, which decreased translocation of Drp1 to mitochondria in DEHP-exposed human GCs. Inhibition of mitochondrial fission reduced intracellular reactive oxygen species (ROS) production, sustained mitochondrial membrane potential and decreased cytochrome c release. Further research showed that AMPK-PGC-1α signal pathway was involved in the inhibition of melatonin on Drp1 expression and activation. Melatonin treatment promoted AMPK activation suppressed by DEHP, and activated AMPK recovered the balance of Drp1 phosphorylation at Ser616 and Ser637 sites and enhanced PGC-1α expression. Moreover, PGC-1α could prevent mitochondrial fission by decreasing Drp1 expression directly via binding to its promoter. In contrast, blocking of AMPK or PGC-1α with specific inhibitor negated the protective effects of melatonin on mitochondrial homeostasis and GCs apoptosis. In summary, our results indicated the protective effects of melatonin on improving mitochondrial function and attenuating cells injury in DEHP-exposed human GCs. Melatonin treatment may be a promising therapeutic approach against DEHP-induced reproductive disorder.

The presence of room temperature phosphorescence emission in metalloporphyrin, via the transition from the excited triplet state (T

High bacterial community diversity and complexity greatly challenge the cost-efficient monitoring of clinically prevalent antibiotic-resistant bacteria, which are usually present as rare and important populations involved in the environmental dissemination of clinical resistance. Here, we introduce culture-enriched phenotypic metagenomics that integrates culture enrichment, phenotypic screening, and metagenomic analyses as an emerging standardized methodology for targeted resistome monitoring and apply it to decipher the extended-spectrum β-lactam resistome in a municipal wastewater treatment plant (WWTP) and its receiving river. The results showed that clinically prevalent carbapenemase genes (e.g., the NDM and KPC families) and extended-spectrum β-lactamase genes (e.g., the CTX-M, TEM, and OXA families) were prevalent in the WWTP and showed prominent potential in horizontal dissemination. Strikingly, carbapenem and polymyxin resistance genes co-occurred in the highly virulent nosocomial pathogens

Although the mass production of synthetic plastics has transformed human lives, it has resulted in waste accumulation on the earth. Here, we report a low-temperature conversion of polyethylene into olefins. By mixing the polyethylene feed with rationally designed ZSM-5 zeolite nanosheets at 280 °C in flowing hydrogen as a carrier gas, light hydrocarbons (C

This study aimed to establish a method for the rapid determination of trace estrogens in honey samples by high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) using imine-linked porous covalent organic framework material (IL-COF-1) as the adsorbent for solid-phase extraction (SPE). Estradiol (E

Although corrective osteotomy with volar or dorsal plate fixation can treat malunion of distal radius fractures, each has its own disadvantages. Little is currently known on whether dorsal fixation combined with volar fixation may further improve recovery. This study aimed to evaluate the clinical value of corrective osteotomy combined with volar and dorsal plate fixation in patients with malunion of intra-articular fractures of the distal radius.Seventeen patients with malunion of intra-articular fractures of the distal radius treated with corrective osteotomy with volar and dorsal plate fixation from 1 January 2016 to 31 November 2018 were retrospectively analyzed. The enrolled patients included seven males and 10 females with an average age of 54.9 years (range: 36-70 years). The radiographic parameters, including the radial length, the radial inclination angle, the ulnar variance, and the volar tilt, as well as clinical outcomes, including wrist and forearm range of motion (ROM), grip strength, the Mayo Modified Wrist Score (MMWS), and the disabilities of the Arm, Shoulder, and Hand (DASH) score, were examined at 3 months and 18 months after operation and compared with the preoperative state. The paired t-test was used for statistical analysis.After corrective osteotomy combined with volar and dorsal plate fixation, all included patients were followed up for 18 months, and there was no surgical site infection. Patients reported postoperative pain due to the irritation of extensor tendon (two cases) and wrist arthritis (two cases). The radial length increased from 1.34 ± 2.34 mm to 9.25 ± 2.65 mm and 9.03 ± 2.47 mm at 3 months and 18 months postoperatively (t = 8.257, 7.954, all p 0.05). The radial inclination angle increased from 6.45° ± 0.76° to 19.35° ± 3.43° and 19.03° ± 3.63° at 3 and 18 months (t = 12.517, 12.122, all p 0.05). The ulnar variance decreased from 5.11 ± 0.23 mm to 1.32 ± 0.31 mm and 1.54 ± 0.62 mm at 3 and 18 months (t = 4.214, 4.895, all p 0.05). The volar tilt was corrected from 4.47° ± 3.46° to 15.51° ± 2.72° and 14.12° ± 2.41°, respectively (t = 11.247, 10.432, all p 0.05). Moreover, wrist ROM increased from 42.53° ± 8.99° to 98.70° ± 7.61° and 101.24° ± 7.66° (t = 41.433, 46.627, all p 0.05), while forearm ROM was increased from 94.82° ± 6.54° to 134.47° ± 5.06° and 137.24° ± 5.52°, respectively (t = 31.507, 32.584, all p 0.05). Similarly, grip strength, MMWS, and DASH were also remarkably improved. There were no significant differences in the wrist and forearm ROM, grip strength, MMWS, and DASH scores between follow-up at 3 and 18 months (all p 0.05).Corrective osteotomy with volar and dorsal fixation can improve recovery of volar tilt, relieve wrist pain, restore wrist and forearm function, and increase grip strength of patients with malunion of intra-articular fractures of the distal radius.

The fine-tuning of the pore structure of metal-organic frameworks (MOFs) is of critical importance to developing energy-efficient processes for the challenging separation of structurally similar molecules. Herein, we demonstrate a strategy to realize a quasi-three-dimensional refinement of the pore structure that utilizes the tunability of ring size and number in polycycloalkane-dicarboxylate ligands. Two hydrolytically stable MOFs with a confined aliphatic pore environment, ZUL-C1 and ZUL-C2, were, for the first time, synthesized and applied in separating low-concentration C2-C3 hydrocarbons from natural gas and ultralow-concentration Xe from used nuclear fuel (UNF) off-gas. Validated by X-ray diffraction and modeling, an expansion of the polycycloalkane moiety enables sub-angstrom contraction in specific directions and forms a pore surface with more alkyl sites, which affords stronger trapping of guest molecules with relatively higher polarizability. The resultant material exhibits record C

The separation and purification of xylene isomers is an industrially important but challenging process. Developing highly efficient adsorbents is crucial for the implementation of simulated moving bed technology for industrial separation of these isomers. Herein, we report a stacked one-dimensional coordination polymer {[Mn(dhbq)(H 2 O) 2 ], H 2 dhbq = 2,5-dihydroxy-1,4-benzoquinone} that exhibits an ideal molecular recognition and sieving of xylene isomers. Its distinct temperature-adsorbate–dependent adsorption behavior enables full separation of p -, m -, and o -xylene isomers in both vapor and liquid phases. The delicate stimuli-responsive swelling of the structure imparts this porous material with exceptionally high flexibility and stability, well-balanced adsorption capacity, high selectivity, and fast kinetics at conditions mimicking industrial settings. This study may offer an alternative approach for energy-efficient and adsorption-based industrial xylene separation and purification processes.