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Based on the high-quality observation data and the numerical simulation, the evolution characteristics of internal solitary waves (ISWs) and the load on the suspend submerged body are studied on the continental shelf and slope separately. The observed ISWs exhibit the first mode depression ISWs. The amplitudes of ISWs on the shelf and slope areas reach 50 m and 80 m, respectively. The upper layer velocity in the westward direction is about 0.8 m/s on the continental shelf and 0.9 m/s on the continental slope during the passing through of ISWs. The lower layer is dominated by the eastward compensating flow. In the vertical direction, the water in front of the wave flows downward, while the water behind the wave flows upward, and the maximum vertical velocity exceeds 0.2 m/s. Numerical simulation results show that the larger the amplitude of ISWs, the larger the load on the submerged body. The force on the submerged body by ISWs is dominated by the vertical force, and the corresponding maximum vertical forces on the continental shelf and slope are −25 kN and −27 kN. The submerged body is subjected to a large counterclockwise moment and the sudden change of the moment will also cause the submerged body to capsize. This paper not only gives a deeper understanding of the characteristics of ISWs from the deep continental slope to the shallow continental shelf, but also has a certain guiding value for the prediction of ISWs and for marine military activities.

Nanogap-based plasmonic metal nanocrystals have been applied in surface-enhanced Raman scattering detection, while the closed and insufficient electromagnetic fields as well as the nonreproducible Raman signal of the substrate greatly restrict the actual application. Herein, a highly uniform Au/AgAu monolayer with abundant nanogaps and huge electromagnetic enhancement is prepared, which shows ultrasensitive and reproducible SERS detection. Au/AgAu with an inner nanogap is first prepared based on Au nanotriangles, and the nanogap is opened from the three tips via a subsequent etching process. The open-gap Au/AgAu displays much higher SERS efficiency than Au and Au/AgAu with an inner nanogap on detecting crystal violet due to the open-gap induced electromagnetic enhancement and improved molecular absorption. Furthermore, the open-gap Au/AgAu monolayer is prepared via interfacial self-assembly, which shows further improved SERS due to the dense and strong hotspots in the nanocavities induced by the electromagnetic coupling between adjacent open gaps. The monolayer possesses excellent signal stability, uniformity, and reproducibility. The analytic enhancement factor and relative standard deviation reach to 2.12 × 108and 4.65% on detecting crystal violet, respectively. Moreover, the monolayer achieves efficient detection of thiram in apple juice, biphenyl-4-thiol, 4-mercaptobenzoic, melamine, and a mixed solution of four different molecules, showing great promise in practical detection.

The design of semiconductors with excellent charge separation and photothermal conversion efficiency is crucial for solar-driven photocatalytic hydrogen production. Herein, a narrow-bandgap semiconductor junction by growing Bi2S3nanosheets on ReS2nanoflowers is designed for efficient photothermal-assisted photocatalytic hydrogen generation. The Bi2S3/ReS2hybrids featuring a distinctive 3D flower-like morphology and 2D/2D heterointerfaces are prepared via a handy method. The synergistic excitations of the narrow bandgaps endow these hybrids with a broad light absorption spectrum, ranging from the ultraviolet to the near-infrared region. Additionally, the Bi2S3/ReS2hybrids demonstrate superior photothermal conversion in both solution and solid states, originating from the efficient light absorption and nonradiative relaxation of lattice thermal vibrations. The well-matched band alignment of the two narrow-bandgap semiconductors confers upon the hybrids a built-in electric field and a Z-scheme charge-transfer pathway, significantly enhancing charge separation and suppressing the charge recombination. Under simulated solar light irradiation, the ReS2/Bi2S3hybrids exhibit a substantially enhanced photocatalytic hydrogen generation rate, which is 38.5 times and 7.36 times that of ReS2and Bi2S3, respectively. Temperature-dependent photocatalytic experiments reveal that the hybrids’ excellent photothermal conversion contributes to about a 23 % improvement on photocatalysis compared to that tested at low temperature. This improvement is attributed to the local temperature rise, which further enhances charge transfer efficiency and the hydrogen reduction reaction. This study offers an inspiration for the design of photocatalysts based on narrow-bandgap semiconductors for photothermal-assisted photocatalysis.

The combination of nucleic acid and small-molecule drugs in tumor treatment holds significant promise; however, the precise delivery and controlled release of drugs within the cytoplasm encounter substantial obstacles, impeding the advancement of formulations. To surmount the challenges associated with precise drug delivery and controlled release, we have developed a multi-level pH-responsive co-loaded drug lipid nanoplatform. This platform first employs cyclic cell-penetrating peptides to exert a multi-level pH response, thereby enhancing the uptake efficiency of tumor cells and endow the nanosystem with effective endosomal/lysosomal escape. Subsequently, small interferring RNA (siRNA) complexes are formed by compacting siRNA with stearic acid octahistidine, which is capable of responding to the lysosome-to-cytoplasm pH gradient and facilitate siRNA release. The siRNA complexes and docetaxel are simultaneously encapsulated into liposomes, thereby creating a lipid nanoplatform capable of co-delivering nucleic acid and small-molecule drugs. The efficacy of this platform has been validated through both in vitroand in vivoexperiments, affirming its significant potential for practical applications in the co-delivery of nucleic acids and small-molecule drugs.

Accumulating evidence indicates that long noncoding RNAs (lncRNAs) act as tumor promoters or suppressors in various types of cancer. Previous investigations suggest that ceramide synthase 6 (CERS6) antisense RNA 1 (CERS6‐AS1) acts as an oncogene in breast cancer; however, its role in colorectal cancer is unknown. This study aimed to explore the molecular mechanism of CERS6‐AS1 in colorectal cancer. Gene expression in colorectal cancer was examined using reverse transcription‐quantitative polymerase chain reaction and western blot analyses. The viability and proliferation of colorectal cancer cells were measured by Cell Counting Kit‐8 assays and colony formation assays. The migratory and invasive capacities of the colorectal cancer cells were assessed by Transwell assay. Cell stemness was examined by sphere‐formation assay. Mechanistically, RNA pull‐down assays, RNA immunoprecipitation assays, and luciferase reporter assays were performed to explore the relationship among CERS6‐AS1, miR‐15b‐5p and spectrin beta, non‐erythrocytic 2 (SPTBN2). Moreover, a xenograft tumor model was established to investigate the role of CERS6‐AS1 in vivo. We found that CERS6‐AS1 and SPTBN2 were highly expressed in colorectal cancer tissues and cells. CERS6‐AS1 depletion inhibited cell viability, proliferation, migration, and invasion; the epithelial‐mesenchymal transition process and stemness. It suppressed xenograft tumor growth in colorectal cancer. Moreover, SPTBN2 levels were positively regulated by CERS6‐AS1 and negatively regulated by miR‐15b‐5p in colorectal cancer cells. Rescue assays revealed that SPTBN2 reversed the inhibitory effect of CERS6‐AS1 deficiency on the malignant behaviors of colorectal cancer cells. Overall, the lncRNA CERS6‐AS1 facilitates malignant phenotypes of colorectal cancer cells by targeting miR‐15b‐5p to upregulate SPTBN2.

A phase junction fabricated by two crystalline phases of the same semiconductor is a promising photocatalyst with efficient charge transfer and separation. However, the weak light absorption and uncontrolled phase junction interface limit the generation and separation of photogenerated carriers. Herein, a two-dimensional (2D)/2D phase junction was prepared by growing orthorhombic WO3ultrathin nanosheets on hexagonal WO3nanosheets through a one-step hydrothermal method. The orthorhombic/hexagonal WO3possesses large-area phase junction interfaces, rich reactive sites, and built-in electric field, which greatly accelerate the photogenerated charge separation and transfer. Thus, the orthorhombic/hexagonal WO3displayed excellent photocatalytic hydrogen generation activity from water splitting under light irradiation (λ > 420 nm), which is 2.16 and 2.85 times those of orthorhombic and hexagonal WO3phase components. Furthermore, Au nanoparticles (about 4.5 nm in diameter) were deposited on both orthorhombic and hexagonal WO3nanosheets to form a plasmon-mediated phase junction. The hybrids exhibit prominent visible-light absorption and efficient charge transfer, leading to a further improved photocatalytic hydrogen generation activity. Further characterization studies demonstrate that superior photoactivity arises from the excellent visible-light-harvesting ability, appropriate band structure, and high-efficiency and multichannel transferring processes of photogenerated carriers.

Introduction: Since December 2019, severe acute respiratory syndrome-related coronavirus-2 (SARS-CoV-2) has caused the coronavirus disease 2019 (COVID-19) pandemic in China and worldwide. New drugs for the treatment of COVID-19 are in urgent need. Considering the long development time for new drugs, the identification of promising inhibitors from FDA-approved drugs is an imperative and valuable strategy. Recent studies have shown that the S1 and S2 subunits of the spike protein of SARS-CoV-2 utilize human angiotensin-converting enzyme 2 (hACE2) as the receptor to infect human cells. Methods: We combined molecular docking and surface plasmon resonance (SPR) to identify potential inhibitors for ACE2 from available commercial medicines. We also designed coronavirus pseudoparticles that contain the spike protein assembled onto green fluorescent protein or luciferase reporter gene-carrying vesicular stomatitis virus core particles. Results: We found that thymoquinone, a phytochemical compound obtained from the plant Nigella sativa, is a potential drug candidate. SPR analysis confirmed the binding of thymoquinone to ACE2. We found that thymoquinone can inhibit SARS-CoV-2, SARS-CoV, and NL63 pseudoparticles infecting HEK293-ACE2 cells, with half-maximal inhibitory concentrations of 4.999, 7.598, and 6.019 μM, respectively. The SARS-CoV-2 pseudoparticle inhibition had half-maximal cytotoxic concentration of 35.100 μM and selection index = 7.020. Conclusion: Thymoquinone is a potential broad-spectrum inhibitor for the treatment of coronavirus infections.

Synthetic cannabinoids, as exemplified by SDB-001 (1), bind to both CB1 and CB2 receptors and exert cannabimimetic effects similar to (−)-trans-Δ9-tetrahydrocannabinol, the main psychoactive component present in the cannabis plant. As CB1 receptor ligands were found to have severe adverse psychiatric effects, increased attention was turned to exploiting the potential therapeutic value of the CB2 receptor. In our efforts to discover novel and selective CB2 receptor agonists, 1was selected as a starting point for hit molecule identification and a class of 1H-pyrazole-3-carboxamide derivatives were thus designed, synthesized, and biologically evaluated. Systematic structure–activity relationship investigations resulted in the identification of the most promising compound 66as a selective CB2 receptor agonist with favorable pharmacokinetic profiles. Especially, 66treatment significantly attenuated dermal inflammation and fibrosis in a bleomycin-induced mouse model of systemic sclerosis, supporting that CB2 receptor agonists might serve as potential therapeutics for treating systemic sclerosis.

Nanogap-based Raman substrates with Raman reporters embedded in the nanogap have been demonstrated to possess superior SERS responses and have found potential applications in molecular detection and sensing. Herein, multigap Au/AgAu hybrids with rhodamine B (RhB) molecules embedded in the nanogap are prepared as gap-enhanced Raman substrates to achieve improved SERS performances. Au/AgAu hybrids with tunable gap widths and counts are synthesized by a controlled galvanic replacement process based on Au nanospheres. The strong and adjustable plasmon coupling in the multigap structure endows Au/AgAu hybrids with prominent plasmon absorption and strong electric fields, endowing the hybrids with outstanding SERS responses. Specially, one-gap Au/AgAu hybrids show tunable enhanced SERS signals by changing the gap width due to the adjustable plasmon coupling. One-gap Au/AgAu hybrids with about a 0.8 nm gap width exhibit the highest SERS signal, and the signal is decreased as the gap width increased from 0.8 to 3.8 nm. Moreover, with RhB molecules fixedly embedded in the first nanogap (width ≈ 1.9 nm), the SERS signals of Au/AgAu hybrids are further improved by adding additional nanogaps. In particular, Au/AgAu hybrids with three gaps possess the highest Raman response, owing to a further enhanced electric field caused by multi-interfacial plasmon coupling. Furthermore, the embedded position of RhB in the four-gap structure is adjusted for higher SERS performance. Four-gap Au/AgAu hybrids with RhB molecules embedded in the third nanogap exhibit the best SERS activity due to the further enhanced electric field, which may be caused by the electric field coupling between the second and fourth nanogaps.

Au nanoingots, on which an Au nanosphere is accurately placed in an open Au shell, are synthesized through a controllable hydrothermal method. The prepared Au nanoingots exhibit an adjustable cavity structure, strong plasmon coupling, tunable magnetic plasmon resonance, and prominent photocatalytic and SERS performances. Au nanoingots exhibit two resonance peaks in the extinction spectrum, one (around 550 nm) is ascribed to electric dipole resonance coming from the central Au, and the other one (650–800 nm) is ascribed to the magnetic dipole resonance originating from the open Au shell. Numerical simulations verify that the intense electric and magnetic fields locate in the bowl-shaped nanogap between the Au nanosphere and shell, and they can be further optimized by changing the size of the outer Au shell. Au nanoingots with the largest shell have the strongest electric field because of large-area plasmon coupling, while Au nanoingots with the largest shell opening size have the strongest magnetic field. As a result, the structure-adjustable Au nanoingots show a high tunability and enhancement of catalytic reduction of p-nitrophenol and SERS detection of Rhodamine B. Specially, Au nanoingots with the largest shell size exhibit the highest catalytic activity and Raman signals at 532 nm excitation. However, Au nanoingots with the largest shell opening size have the highest photocatalytic activity with light irradiation (λ > 420 nm) and exhibit the best SERS performance at 785 nm excitation.

The Droughtmaster is a tropical breed of beef cattle developed in North Queensland that exhibits a combination of heat resistance and parasitic resistance from long-term artificial selection. Therefore, we used next-generation sequencing technology to screen the chromosomal regions and genes related to heat-resistance in cattle to provide data for improving cattle breeding. A total of 15,569,067 variants including 14,249,316 SNPs were obtained from two mixed pools by genome-wide resequencing. According to the results of the selective sweep analysis of the Droughtmaster pool compared to the nonheat resistant breeds pool, 81 candidate genes under selection in Droughtmaster were identified by combining ZHP and FSTanalyses with a threshold standard of the top 1%, including SLC7A11, GYPC, and GYPC. In addition, 40 GO terms and 44 pathways were annotated from newly identified candidate genes. These signaling pathways were involved in environmental information processing, organismal systems, and metabolism. A majority of these genes have not been implicated in the previous studies of heat resistance. This study explored the genomic changes that result from long-term artificial selection, our findings help to explain the molecular mechanism of heat resistance in cattle.

The piezoelectric composite material could engender stress concentration resulting from small cracks during layers easily, as the cracks growth will lead to the failure of the whole structure. In this paper, a finite element model for piezoelectric composite materials by ABAQUS including interlayer crack was established, and the J integral and crack tip stress of different types PZT patches were calculated by using the equivalent integral method. Then, the J integral for adhesive layers with different thickness, elastic modulus considering and not considering piezoelectricity was investigated. The results show that the J integral of mode I, II reduces with thicker adhesive layer and lower elastic modules, and the J integral of mode II decreases more sharply than that of mode I.

In order to overcome the difficulty of easily falling into the local minimum solution during the optimization process of heat exchanger network which is not considered fixed investment costs, an innovative method was presented. The total areas of local minimum solution were distributed equally, and then the distributed areas were assigned to initial areas for further optimization. The better local minimum solution was sought out after jumping out of local minimum solution. Through some case study, it presents that this optimization method is able to obtain better optimization results which is more suitable to industrial applications.

The buckling and delamination propagation behavior in delaminated piezoelectric stiffened composite plates subjected to combined applied voltage and compressive loading are studied. The cohesive element for the non-linear finite element software ABAQUS is used to simulate the interface of the delamination region in the composite plates. The numerical simulation is conducted by using piezoelectric solid element and conventional shell element. The delamination propagation and the failure of stiffened composite plates are predicted by strength-based and energy-based criteria. The bucking control effect for the different buckling of piezoelectric stiffened composite plates with applied voltage was investigated, and the delamination propagation behavior of stiffened composite plates with piezoelectric actuators was studied. The results obtained by numerical analysis indicate that the appropriate control by piezoelectric actuators can retard local buckling of delaminated sub-laminates and prevent delamination growth effectively.

This study deals with the transient response of heat exchanger which is approximated to the first-order system with delay. This function is of simple form and easy to be applied to design the practical controllers. The parameters such as gain K, time constant T and delay time are derived in this paper. On the basis of using the first-order system as the transfer function for a heat exchanger, more accurate models are built to derive the parameters K, T and respectively, which are constructed with a lumped parameter approach. Unlike a number of recent analyses K is obtained by using arithmetic mean temperature difference, log mean temperature difference has been employed instead, which minimized the error; time constant T is obtained by deriving the time constant of baffle; delay time is estimated by flow rate. The result shows that this method to study the dynamic characteristics of heat exchanger is easier, more accurate.

The angular distribution of the 2H(8Li, 9Be)n (ground state) reaction, important to primordial nucleosynthesis in the inhomogeneous model, has been measured at Ec.m. = 8.1 MeV using a secondary 8Li beam. Cross section of this reaction was determined to be 9.0±3.4 mb. According to the cross section, the astrophysical S-factor was calculated to be 272±103 keV b. It is shown that 2H(8Li, 9Be)n (ground state) reaction is important for creating 9Be, but less important for destroying 8Li in primordial nucleosynthesis.

The metal-organic framework MOF-5 was synthesized by self-assembling of Zn(NO3)2·7H2O and H2BDC using DMF as solvent by the direct precipitation method and loaded with Fe2+ by the equivalent loading method at room temperature to prepare Fe(II)/MOF-5 catalyst and the microstructure, phases, and pore size of which was characterized by IR, XRD, SEM, TEM, and BET. It was found that Fe(II)/MOF-5 had high specific surface and porosity like MOF-5 and uniform pore distribution, and the pore size is 1.2 nm. In order to study the catalytic activity and reaction conditions of Fe(II)/MOF-5, it was used to catalyze the hydroxylation reaction of phenol with hydrogen peroxide. The results showed that the dihydroxybenzene yield of 53.2% and the catechol selectivity of 98.6% were obtained at the Fe2+ content of 3 wt.%, the mass ratio of Fe(II)/MOF-5 to phenol of 0.053, the reaction temperature of 80°C, and the reaction time of 2 h.

Needle embedding at the first region of ankle acupuncture plus fomentation was used to treat 18 orchitis cases. The curative rate was 100%.