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C40H42O14N8Cl4Cd, triclinic, P1̄ (no. 2), a = 7.5892(16) Å, b = 7.6583(15) Å, c = 20.629(4) Å, α = 79.620(4)°, β = 84.594(3)°, γ = 79.427(4)°, V = 1157.0(4) Å3, Z = 1, Rgt(F) = 0.0721, wRref(F2) = 0.1967, T = 296(2) K. [ABSTRACT FROM AUTHOR]

Despite industrial bio-manufacturing progress using Bacillus licheniformis , the absence of a well-characterized toolbox allowing precise regulation of multiple genes limits its expansion for basic research and application. Here, a novel gene expression toolbox (GET) was developed for precise regulation of gene expression and high-level production of 2-phenylethanol. Firstly, we established a novel promoter core region mosaic combination model to combine, characterize and analyze different core regions. Characterization and orthogonal design of promoter ribbons allowed convenient construction of an adaptable and robust GET, gene gfp expression intensity was 0.64%–16755.77%, with a dynamic range of 2.61 × 104 times, which is the largest regulatory range of GET in Bacillus based on modification of promoter P43. Then we verified the protein and species universality of GET using different proteins expressed in B. licheniformis and Bacillus subtilis. Finally, the GET for 2-phenylethanol metabolic breeding, resulting in a plasmid-free strain producing 6.95 g/L 2-phenylethanol with a yield and productivity of 0.15 g/g glucose and 0.14 g/L/h, respectively, the highest de novo synthesis yield of 2-phenylethanol reported. Taken together, this is the first report elucidating the impact of mosaic combination and tandem of multiple core regions to initiate transcription and improve the output of proteins and metabolites, which provides strong support for gene regulation and diversified product production in Bacillus. • A novel promoter core region mosaic combination model to improve promoter performance. • An adaptable and wide-range gene expression toolbox that expands the Bacillus Synthetic biology toolbox. • The toolbox has great application value in Bacillus protein expression and metabolic engineering breeding. [ABSTRACT FROM AUTHOR]

This paper presents the first study of the rotations of rigid molecules in 3 dimensions at the air/water interface, using the femtosecond time resolved sum frequency generation (SFG) technique. For the purpose of this research, the aromatic dye molecule C153 was chosen as an example of a molecule having two functional groups that are SFG active, one being the hydrophilic —C=O group and the other the hydrophobic —CF3 group. From polarized SFG measurements, the orientations of the two chromophores with respect to the surface normal were obtained. On combining these results with the known relative orientation of the two chromophores in the molecule yields the absolute orientation of C153 at the air/water interface. It was found that the —CF3 axis projected towards the bulk air at an angle of 59° with respect to the interface normal and the —C=O group projected towards the bulk water at an angle of 144°. In order to observe the rotational motions of C153 at the air/water interface, the approach was used to perturb the ground electronic state equilibrium orientational distribution using a polarized resonant pump pulse, which preferentially excites ground state molecules that have their electronic S0 → S1 transition moment aligned closely to the electric field of the incident pump pulse. As a consequence of the photoselection perturbation, the orientational distribution of the remaining ground state molecules was not the equilibrium distribution. Similarly, the orientational distribution of the excited state molecules that were created by the polarized pump pulse was not in their final equilibrium orientational distribution. The rotational motions of the interfacial molecules towards equilibrium were obtained from time dependent measurements of the intensities of the SFG signal generated by the simultaneous incidence at the air/water interface of a visible probe pulse plus an IR probe pulse. In this way, the recovery times to achieve the orientational equilibrium of the two chromophores including the orientation of the normal of the C153 plane with respect to the interface were obtained. The photo-selection process shifts the average orientation angle of the hydrophilic —C=O group by an increase of 4° ± 0.6° with a rotational recovery time constant of 130 ± 20 ps, which is the time to return to an orientational equilibrium distribution. The hydrophobic –CF3 group undergoes a shift that increases its angle by 8° ± 1.5° with a rotational recovery time constant of 210 ± 38 ps. We find that the orientational change of the molecular normal is 4° ± 0.5° and has a rotational recovery time constant of 125 ± 26 ps. The interface-specific time-dependent polarized measurements allowed us to monitor the orientational motions of molecules at interfaces, both in 3 dimensions and in real time. [ABSTRACT FROM AUTHOR]

Background: Image registration has long been an active research area in the society of medical image computing, which is to perform spatial transformation between a pair of images and establish a point‐wise correspondence to achieve spatial consistency. Purpose: Previous work mainly focused on learning complicated deformation fields by maximizing the global‐level (i.e., foreground plus background) image similarity. We argue that taking the background similarity into account may not be a good solution, if we only seek the accurate alignment of target organs/regions in real clinical practice. Methods: We, therefore, propose a novel concept of Salient$Salient$Registration$Registration$ and introduce a novel deformable network equipped with a saliency module. Specifically, a multitask learning‐based saliency module is proposed to discriminate the salient regions‐of‐registration in a semisupervised manner. Then, our deformable network analyzes the intensity and anatomical similarity of salient regions, and finally conducts the salient deformable registration. Results: We evaluate the efficacy of the proposed network on challenging abdominal multiorgan CT scans. The experimental results demonstrate that the proposed registration network outperforms other state‐of‐the‐art methods, achieving a mean Dice similarity coefficient (DSC) of 40.2%, Hausdorff distance (95 HD) of 20.8 mm, and average symmetric surface distance (ASSD) of 4.58 mm. Moreover, even by training using one labeled data, our network can still attain satisfactory registration performance, with a mean DSC of 39.2%, 95 HD of 21.2 mm, and ASSD of 4.78 mm. Conclusions: The proposed network provides an accurate solution for multiorgan registration and has the potential to be used for improving other registration applications. The code is publicly available at https://github.com/Rrrfrr/Salient‐Deformable‐Network. [ABSTRACT FROM AUTHOR]

BACKGROUND: The anterior cruciate ligament (ACL) reconstruction (ACLR) under the arthroscopy is a widespread procedure for ACL rupture, which could stabilize knee and promote recovery. However, one of its complications is the injury of infrapatellar branch of saphenous nerve (IBSN). In traditional Chinese medicine, acupotomy functions via releasing and stripping adhesion tissues. Accordingly, acupotomy is suitable for the treatment of entrapped nerve injury and tissues adhesion. CASE DESCRIPTION: A 14-year-old man, who had ACLR before and returned to normal activity, presented with severe pain after a mild strain two weeks ago. The physical and imaging examinations revealed the compression injury of IBSN. METHODS: We provided the ultrasound-guided perineural injection of 0.4% lidocaine, while it only alleviates the symptoms temporally and partially. Acupotomy using a small needle knife (0.4*40 mm) was performed. RESULTS: The severe pain was immediately resolved. The visual analog pain scale (VAS) decreased from 10 to 1 and return to normal walking. The diameter of IBSN became smaller and the signal of peripheral soft tissue became hypoechoic in ultrasound. CONCLUSION: : In this case, the combined treatments of ultrasound-guided perineural injection and acupotomy are thought to be innovative procedures for IBSN entrapment with relative long-lasting therapeutic effects. [ABSTRACT FROM AUTHOR]

Molecular doping is an of significance approach to reduce defects density of perovskite and to improve interfacial charge extraction in perovskite solar cells. Here, we show a new strategy for chemical doping of perovskite via an organic small molecule, which features a fused tricyclic core, showing strong intermolecular π‐Pb2+ interactions with under‐coordinated Pb2+ in perovskite. This π‐Pb2+ interactions could reduce defects density of the perovskite and suppress the nonradiative recombination, which was also confirmed by the density functional theory calculations. In addition, this doping via π‐Pb2+ interactions could deepen the surface potential and downshift the work function of the doped perovskite film, facilitating the hole extraction to hole transport layer. As a result, the doped device showed high efficiency of 21.41 % with ignorable hysteresis. This strategy of fused tricyclic core‐based doping provides a new perspective for the design of new organic materials to improve the device performance. [ABSTRACT FROM AUTHOR]

Molecular doping is an of significance approach to reduce defects density of perovskite and to improve interfacial charge extraction in perovskite solar cells. Here, we show a new strategy for chemical doping of perovskite via an organic small molecule, which features a fused tricyclic core, showing strong intermolecular π‐Pb2+ interactions with under‐coordinated Pb2+ in perovskite. This π‐Pb2+ interactions could reduce defects density of the perovskite and suppress the nonradiative recombination, which was also confirmed by the density functional theory calculations. In addition, this doping via π‐Pb2+ interactions could deepen the surface potential and downshift the work function of the doped perovskite film, facilitating the hole extraction to hole transport layer. As a result, the doped device showed high efficiency of 21.41 % with ignorable hysteresis. This strategy of fused tricyclic core‐based doping provides a new perspective for the design of new organic materials to improve the device performance. [ABSTRACT FROM AUTHOR]

The nanopore-based translocation of a single-stranded RNA (ssRNA) in mixed salt solution has garnered increasing interest for its biological and technological significance. However, it is challenging to comprehensively understand the effects of the mixed ion species on the translocation dynamics due to their cooperation and competition, which can be directly reflected by the ion screening and neutralizing effects, respectively. In this study, Langevin dynamics simulation is employed to investigate the properties of ssRNA conformation and translocation in mixed Na+-Mg2+ ion environments. Simulation results reveal that the ion screening effect dominates the change in the ssRNA conformational size, the ion neutralizing effect controls the capture rate of the ssRNA by the nanopore, and both of them take charge of the different changes in translocation time of the ssRNA under various mixed ion environments. Under high Na+ ion concentration, as Mg2+ concentration increases, the ion neutralizing effect strengthens, weakening the driving force inside the nanopore, leading to longer translocation time. Conversely, at low Na+ concentration, an increase in Mg2+ concentration enhances the ion screening effect, aiding in faster translocation. Furthermore, these simulation results will be explained by quantitative analysis, advancing a deeper understanding of the complicated effects of the mixed Na+-Mg2+ ions. • ssRNA translocation in mixed Na+/Mg2+ ion environment is studied by simulations. • Mixed ions cooperate to modify screening effect, influencing ssRNA conformation. • Mixed ions compete to impact neutralizing effect, altering capture rate by nanopore. • Mixed ions exert cooperating/competing effects on ssRNA translocation behaviors. [ABSTRACT FROM AUTHOR]

Ni-based bimetallic catalysts with noble metals exhibit high activity and selectivity for hydrogen generation from hydrazine monohydrate. However, their poor service durability remains a critical challenge. This study investigated the use of Zn-doped CeO 2 as a support for Ni–Pt catalysts to improve their long-term stability. A series of Ni–Pt/Zn-doped-CeO 2 catalysts were prepared via a simple co-precipitation and reduction method. Compared to the pristine Ni 50 Pt 50 /CeO 2 catalyst, the Zn doping can improve the stability of CeO 2 support in the alkaline condition, and the X-ray photoelectron spectroscopy (XPS) analysis clearly indicates that Zn doping leads to a negative shift in the binding energy of connected Ni and thus enhances the stability of the electronic structure in the catalysts. The findings in this work suggest that Zn-modified CeO 2 supporting Ni–Pt catalyst offer a promising approach to achieving a better balance between activity and durability for hydrogen generation catalysts. • Ni–Pt/Zn-doped CeO 2 catalysts was prepared via a simple co-precipitation method. • The Ni 50 Pt 47.5 /Zn 2.5 catalyst exhibits excellent performance: ■ 100% H 2 selectivity ■ TOF of 2000 h−1 at 323 K in 2.5 M NaOH ■ Satisfactory stability after 10 cycles (TOF of 1800 h−1) • Ni–Pt/Zn-doped CeO 2 catalysts leverages the high activity and selectivity of Ni-Pt alloys for hydrazine decomposition while incorporating Zn to tune the CeO 2 support, and replacing Pt with Zn to reduce costs. [ABSTRACT FROM AUTHOR]

• Dual promoters significantly enhanced gene expression levels both at log and stationary phases. • An efficient dual-promoter Pdual3 was attained via coupling the sigB- and sigA-type promoters and sequence optimization. • The yields of heterologous proteins and target metabolites were all significantly enhanced by means of promoter Pdual3. Promoter plays the critical role in regulating gene transcription, and dual-promoter has received the widespread attentions due to its high efficiency and continuity, here, we want to construct an efficient dual-promoter for protein production and metabolic pathway enhancement. Firstly, our results indicated that P43 promoter efficiently transcribed at logarithmic period, while the σB-type promoters (PylB, PgsiB, PykzA) were active at stationary phase. Then, several dual promoters were constructed by coupling these σB-type promoters with P43, and the attained dual-promoter PykzA-P43 showed the best performance, which led to 1.72-, 3.46- and 1.85-fold increases of green fluorescence intensity, red fluorescence intensity and α-amylase activity, compared with those of the recognized strong promoter P43, respectively. Furthermore, α-amylase activity was further increased to 389.65 U/mL by 32.20 % via optimizing sigma factor binding sites (-10 and -35 boxes) of PykzA-P43, attaining the optimized dual promoter Pdual3. Finally, Pdual3 was applied in metabolic pathway enhancement, and the yields of Poly γ-glutamic acid, acetoin and 2, 3-butanediol were respectively improved by 82.01 %, 17.09 % and 99.39 %. Our results indicated that dual-promoter significantly enhanced gene expression, and this study provided an energetic dual-promoter Pdual3 for efficient protein production and metabolic pathway enhancement in Bacillus licheniformis. [ABSTRACT FROM AUTHOR]

The movements of molecules at interfaces and surfaces are restricted by their asymmetric environments, leading to anisotropic orientational motions. In this work, in-plane orientational motions of the –C=O and –CF3 groups of coumarin 153 (C153) at the air/water interface were measured using time-resolved (TR) vibrational sum frequency generation (SFG). The in-plane orientational time constants of the –C=O and –CF3 groups of C153 are found to be 41.5 ± 8.2 and 36.0 ± 4.5 ps. These values are over five-times faster than that of 198 ± 15 ps for the permanent dipole of the whole C153 molecule at the interface, which may indicate that the two groups experience different interfacial friction in the plane. These differences could also be the result of the permanent dipole of C153 being almost five times those of the –C=O and –CF3 groups. The difference in orientational motions reveals the microscopic heterogeneous environment that molecules experience at the interface. While the interfacial dynamics of the two functional groups are similar, our TR-SFG experiments allowed the quantification of the in-plane dynamics of individual functional groups for the first time. Our experimental findings about the interfacial molecular motion have implications for molecular rotations, energy transfer, and charge transfer at material interfaces, photocatalysis interfaces, and biological cell/membrane aqueous interfaces. [ABSTRACT FROM AUTHOR]

It is not often that three misconceptions are associated with one molecule for more than a century. This is the case with adrenaline. The aim here is to clarify that adrenaline was the first hormone, with the discovery of its activity and chemical purification being prior to secretin. Adrenaline is the correct name given by Jōkichi Takamine, epinephrine being its inactive benzoyl derivative. [ABSTRACT FROM AUTHOR]

Abstract The wide applications and unintended generation of ozone stimulate the exploration of catalysts for ozone decomposition. Herein, manganese oxides loaded on porous ceramic beads were prepared via a simple thermolysis method. Doping the composite with Ni, Fe, and Al could tune the oxygen vacancies in the manganese oxide, as evidenced by the X-ray photoelectron spectroscopy (XPS) analysis. The average valance of Mn could also be altered by the dopants. The catalytic properties of the composites doped with Fe, Ni, and Al have been significantly improved. And the Ni doped MnO x with the highest density of oxygen vacancy exhibits the best catalytic activity. The prepared composite catalyst can easily be incorporated into filters for air circulation. [ABSTRACT FROM AUTHOR]

Two-dimensional electronic spectroscopy (2D-ES) has become an important technique for studying energy transfer, electronic coupling, and electronic–vibrational coherence in the past ten years. However, since 2D-ES is not interface specific, the electronic information at surfaces and interfaces could not be demonstrated clearly. Two-dimensional electronic sum-frequency generation (2D-ESFG) is an emerging spectroscopic technique that explores the correlations between different interfacial electronic transitions and is the extension of 2D-ES to surface and interfacial specificity. In this work, we present the detailed development and implementation of phase-cycling 2D-ESFG spectroscopy using an acousto-optic pulse shaper in a pump–probe geometry. With the pulse pair generated by a pulse shaper rather than optical devices based on birefringence or interference, this 2D-ESFG setup enables rapid scanning, phase cycling, and the separation of rephasing and nonrephasing signals. In addition, by collecting data in a rotating frame, we greatly improve experimental efficiency. We demonstrate the method for azo-derivative molecules at the air/water interface. This method could be readily extended to different interfaces and surfaces. The unique phase-cycling 2D-ESFG technique enables one to quantify the energy transfer, charge transfer, electronic coupling, and many other electronic properties and dynamics at surfaces and interfaces with precision and relative ease of use. Our goal in this article is to present the fine details of the fourth-order nonlinear optical technique in a manner that is comprehensive, succinct, and approachable such that other researchers can implement, improve, and adapt it to probe unique and innovative problems to advance the field. [ABSTRACT FROM AUTHOR]

Novel vanadium sulfides interwoven nanoflowers supported on nickel foam (VO-S/NF) has been synthesized through a facile two-step access. Firstly, octahedron-structured vanadium oxides as precursor were anchored on the surface of NF (VO/NF) by a hydrothermal process. Secondly, in-situ sulfurization in H 2 S gas has been applied to prepare VO-S/NF. XRD shows that VO-S/NF sample is composed of mixture phases including VS and Ni 3 S 2 , implying the interface effect between VS and Ni 3 S 2 . SEM images demonstrate that octahedron-structured VO from VO/NF changed to VO-S interwoven nanoflowers on VO-S/NF, which are composed of vertical interwoven nanosheets. It can enlarge surface area to expose abundant active sites and facilitate mass and charge transportation. The electrochemical measurements display the enhanced HER activity of VO-S/NF requiring an overpotential of 165 mV to deliver 10 mA cm −2 , which may be ascribed to the novel structure of VS interwoven nanosheets and the synergistic effect between VS and Ni 3 S 2 . Furthermore, VO-S/NF remains high HER activity for at least 10 h with excellent structural stability confirmed by post-HER characterization such as XRD, SEM and XPS. Therefore, it may provide a new way to design multiple transition metal sulfides-based electrocatalysts with unique nanostructure as well as interface effect for HER in alkaline. [ABSTRACT FROM AUTHOR]

A facile sulfurization process has been utilized to synthesize WS 2 /WO 3 heterostructure using WO 3 square nanosheets as support. The thin WO 3 nanosheets synthesized by hydrothermal method may provide large surface area with homogeneous dispersion, which is favorable for exposing active sites and fast charge transfer for hydrogen evolution reaction (HER). SEM and TEM images show that the thin square nanosheets of as-prepared WS 2 /WO 3 heterostructure are well kept after sulfurization process. The formation of WS 2 on the surface of heterostructured nanosheets may greatly enhance the intrinsic HER activity and conductivity. The electrochemical measurements demonstrate the obviously enhanced HER activity of WS 2 /WO 3 heterostructured nanosheets compared with pure WO 3 or bulk WS 2 , illustrating that the synergistic effect derived from heterostructured WS 2 /WO 3 may be a key to enhance HER performances of WO 3 . Therefore, designing heterostructure of transition metal sulfides/oxides may be a promising strategy to prepare efficient electrocatalysts for HER. [ABSTRACT FROM AUTHOR]

Rapid expansion in microelectronic devices has prompted increasing research efforts in development of high-frequency electromagnetic wave absorption materials. Multiple-phase FeSn 2 /Sn/Graphite core–shell nanoparticles synthesized by an arc-discharge method, with controllable components and structures, present a typical cloaking feature aroused from the superior electromagnetic wave absorption. Based on transmission line theory, we prove quantitatively that more than 90% of the electromagnetic power can be attenuated at 9–18 GHz. Experimental results coupled with theory calculations by the Cole–Cole equation and the eddy-current model, further reveal that such high performances are originated from the onion-type interfacial architecture at nanoscale and the desirable impedance match resulting from multiple phase components. [ABSTRACT FROM AUTHOR]

MonolayerMoS2is a direct-gap two-dimensional semiconductorthat exhibits strong electron–hole interactions, leading tothe formation of stable excitons and trions. Here we report the existenceof efficient exciton–exciton annihilation, a four-body interaction,in this material. Exciton–exciton annihilation was identifiedexperimentally in ultrafast transient absorption measurements throughthe emergence of a decay channel varying quadratically with excitondensity. The rate of exciton–exciton annihilation was determinedto be (4.3 ± 1.1) × 10–2cm2/s at room temperature. [ABSTRACT FROM AUTHOR]

The transacting activator of transduction (TAT) protein plays a key role in the progression of AIDS. Studies have shown that a +8 charged sequence of amino acids in the protein, called the TAT peptide, enables the TAT protein to penetrate cell membranes. To probe mechanisms of binding and translocation of the TAT peptide into the cell, investigators have used phospholipid liposomes as cell membrane mimics. We have used the method of surface potential sensitive second harmonic generation (SHG), which is a label-free and interface-selective method, to study the binding of TAT to anionic 1-palmitoyl-2-oleoyl-sn-glycero-3-phospho-1'-rac-glycerol (POPG) and neutral 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) liposomes. It is the SHG sensitivity to the electrostatic field generated by a charged interface that enabled us to obtain the interfacial electrostatic potential. SHG together with the Poisson-Boltzmann equation yielded the dependence of the surface potential on the density of adsorbed TAT. We obtained the dissociation constants Kd for TAT binding to POPC and POPG liposomes and the maximum number of TATs that can bind to a given liposome surface. For POPC Kd was found to be 7.5 ± 2 μM, and for POPG Kd was 29.0 ± 4.0 μM. As TAT was added to the liposome solution the POPC surface potential changed from 0 mV to +37 mV, and for POPG it changed from -57 mV to -37 mV. A numerical calculation of Kd, which included all terms obtained from application of the Poisson-Boltzmann equation to the TAT liposome SHG data, was shown to be in good agreement with an approximated solution. [ABSTRACT FROM AUTHOR]

Second harmonic generation (SHG)was used to selectively probeDNA–drug interactions without the need for chemical labelsor invasive detection methods. In particular, the binding constantof the anticancer drug daunomycin to a recognition triplet sequencein a 33-mer of double stranded DNA was determined. The SHG method,which is interface selective, probed the binding of daunomycin toDNA that was tethered to the surface of colloidal microparticles suspendedin aqueous solution. Probing biomolecule coated colloids is expectedto yield larger SH signals and provides experimental flexibility ascompared to experiments performed at planar interfaces. The changein SHG intensity as daunomycin was added to the microparticle solutionwas fit to a Langmuir binding model, which yielded an equilibriumconstant of 2.3 (±0.7) × 105M–1; the corresponding Gibbs free energy change at 20 °C is −7.2± 0.2 kcal/mol. Control experiments established that daunomycinpreferentially binds to DNA at the recognition sequence. The equilibriumwas found to be unaffected by the presence of free DNA in solution,and hyper-Rayleigh scattering from bulk molecules did not change withincreasing daunomycin concentration. The extracted equilibrium constantsare in agreement with the range of reported values found in the literature. [ABSTRACT FROM AUTHOR]

Highlights: [•] Cu atom tends to occupy the core position in the Ag–Cu nanoclusters. [•] Global minimum of Ag12Cu1 cluster is predicted to be cuboctahedral shape. [•] High symmetry clusters have high magnetic moment. [•] Icosahedral core–shell Ag12Cu1 cluster has ferromagnetic properties. [Copyright &y& Elsevier]

We have measured optical second-harmonicgeneration (SHG) fromatomically thin samples of MoS2and h-BN with one to fivelayers. We observe strong SHG from materials with odd layer thickness,for which a noncentrosymmetric structure is expected, while the centrosymmetricmaterials with even layer thickness do not yield appreciable SHG.SHG for materials with odd layer thickness was measured as a functionof crystal orientation. This dependence reveals the rotational symmetryof the lattice and is shown to provide a purely optical method ofdetermining the orientation of crystallographic axes. We report valuesfor the nonlinearity of monolayers and odd-layers of MoS2and h-BN and compare the variation as a function of layer thicknesswith a model that accounts for wave propagation effects. [ABSTRACT FROM AUTHOR]

We have measured the terahertz frequency-dependent sheetconductivityand its transient response following femtosecond optical excitationfor single-layer graphene samples grown by chemical vapor deposition.The conductivity of the unexcited graphene sheet, which was spontaneouslydoped, showed a strong free-carrier response. The THz conductivitymatched a Drude model over the available THz spectral range and yieldedan average carrier scattering time of 70 fs. Upon photoexcitation,we observed a transient decreasein graphene conductivity.The THz frequency-dependence of the graphene photoresponse differsfrom that of the unexcited material but remains compatible with aDrude form. We show that the negative photoconductive response arisesfrom an increase in the carrier scattering rate, with a minor offsettingincrease in the Drude weight. This behavior, which differs in signfrom that reported previously for epitaxial graphene, is expectedfor samples with relatively high mobilities and doping levels. Thephotoinduced conductivity transient has a picosecond lifetime andis associated with nonequilibrium excitation conditions in the graphene. [ABSTRACT FROM AUTHOR]

Understandings of population and relaxation of charges at surfaces and interfaces are essential to improve charge collection efficiency for energy conversion, catalysis, and photosynthesis. Existing time-resolved surface and interface tools are limited to either under ultrahigh vacuum or in a narrow wavelength region with the loss of spectral information. There lacks an efficient time-resolved surface/interface-specific electronic spectroscopy under ambient conditions for the ultrafast surface/interface dynamics. Here we developed a novel technique for surface/interface-specific broadband electronic sum frequency generation (ESFG). The broadband ESFG was based on a stable two-stage BiB3O6 crystal-based optical parametric amplifier, which generates a strong broadband short-wave infrared (SWIR) from 1200 nm to 2400 nm. A resultant surface spectrum covers almost all visible light from 480 nm to 760 nm, combined a broadband electronic second harmonic generation (ESHG) with the ESFG from the SWIR laser source. We further developed the steady-state and transient broadband ESFG and ESHG techniques to investigate the structure and dynamics of charges at oxidized p-type GaAs (100) semiconductor surfaces, as an example. Both the steady-state and transient experiments have shown that two surface states exist inside the bandgap of the GaAs. The kinetic processes at the GaAs surface include both the population and recombination of the surface states after photoexcitation, in addition to the build-up of the space photo-voltage (SPV). The build-up SPV occurs with a rate of 0.56 ± 0.07 ps−1, while the population rate of the surface states exhibits a two-body behavior with a rate constant of (0.012 ± 0.002) × 1012 s−1 cm2. The photo-generated electron-hole pairs near the surface recombine with a rate of 0.002 ± 0.0002 ps−1 for the oxidized p-type GaAs (100). All the methodologies developed here are readily applied to any optically accessible interfaces and surfaces, in particular buried interfaces under ambient conditions. [ABSTRACT FROM AUTHOR]

Abstract: Femtosecond time resolved vibrational sum frequency generation has been used for the first time to probe a chemical reaction involving interfacial molecules pumped into their excited electronic states. The ultrafast dynamics of electron transfer from ground state N,N-dimethylaniline (DMA) to photoexcited coumarin 314 at a water/DMA monolayer interface was obtained. The forward electron transfer time constant is 16±2ps, which is faster than electron transfer in bulk DMA. The faster rate is attributed to a lower reorganization free energy, which is a consequence of lower interfacial polarity. The back electron transfer time constant is 174±21ps. [Copyright &y& Elsevier]

Abstract: Direct spectroscopic evidence of the presence of organic phenolate ions at the air/aqueous interface has been established using the nonlinear spectroscopic technique of vibrational sum frequency generation (SFG). By probing the phenol C–OH and the phenolate C–O− vibrational stretches, which occur in the range of 1200–1300cm−1 and are distinguishable, we have succeeded in determining the identities of the chemical species present at the air/aqueous interface of phenol–phenolate solutions at bulk pH values ranging from 3.2 to 13.2. We have found that in addition to phenolate ions that phenol is present at the interface at high bulk pH values. [Copyright &y& Elsevier]

Long-range surface plasmon polariton (LRSPP) modes guided by a thin metal film surrounded by semi-infinite dielectrics with different refractive indices are studied. Our calculation results show that the cutoff thickness of the metal film does not monotonically increase with refractive index difference Dn between the substrate and superstrate. Just because of this abnormal behaviour of cutoff thickness, the existence of LRSPP illustrates complicated situations in asymmetric configurations. For a certain metal film thickness, LRSPP may exist in one, two or three refractive index difference Dn regions. [ABSTRACT FROM AUTHOR]

Abstract: We investigated the roles of netrin-1 and slit-2 in regulation and navigation of dopamine (DA) axon growth using an explant culture preparation of embryonic ventral midbrain (embryonic day 14) and a co-culture system. We found that netrin-1 protein significantly enhanced DA axonal outgrowth and promoted DA axonal outgrowth in a co-culture system of netrin-1 expressing cells. Such effects were mediated by the receptor DCC as demonstrated by antibody perturbation of the DCC receptor. In contrast, slit-2 inhibited DA neuron extensions and repelled DA neurite growth. These slit-2 activities required robo receptors since the reduced neurite extension was abolished by addition of excess robo receptors. In this system, netrin-1 stimulated and slit-2 opposed DA neurite growth. Such regulation may be important for DA axonal maintenance, regeneration, and phenotypic target recognition. [Copyright &y& Elsevier]

We present the observation of the direct S2 → S0 two-photon fluorescence (TPF) of crystal violet (CV) in methanol solution. The S2 → S0 emission spectra of CV with excitation wavelengths from 730 to 900 nm are obtained for the first time. These spectra present three clear features: the broad S2 → S0 TPF (370−480 nm) peaked at 408 nm, the hyper-Rayleigh scattering (HRS) at half of the excitation wavelength, and the hyper-Raman scattering with a Stokes shift about 1415 cm-1 from the HRS wavelength, which can be attributed to the phenyl groups in the CV molecule. The two-photon excitation spectra measured from this S2 → S0 emission is peaked at 374 ± 2 nm. This TPF emission has the same depolarization ratio as the HRS signal, indicating a lifetime much shorter than the rotational relaxation lifetime. Subtraction of the TPF contribution leads to a hyperpolarizability value of CV at 800 nm, which is much smaller than that previously reported. Moreover, with the ability to directly measure HRS of the pure solvent, the hyperpolarizability value of CV also has much higher precision. [ABSTRACT FROM AUTHOR]

Human immunodeficiency virus protease inhibitors induce hyperlipidemia in many patients treated with these drugs. We examined the effects of indinavir on cholesterol and bile acid homeostatic mechanisms in a primary rat hepatocyte (PRH) culture model. In PRH, indinavir up-regulated (2.5-fold) 3-hydroxy-3-methylglutaryl-Coenzyme A reductase mRNA levels 24 hr after drug addition. In these same experiments, cholesterol 7α-hydroxylase (CYP7A1) mRNA levels, the rate-limiting enzyme in bile acid biosynthesis, was decreased up to 10-fold. Fatty acid synthase mRNA levels were up-regulated more than 3-fold under these conditions. Indinavir did not alter CYP7A1 transcriptional activity, but decreased CYP7A1 mRNA half-life in PRH from 1.5 hr to less than 0.5 hr. Sterol regulatory element-binding protein-1 (SREBP-1) mature form was increased approximately 6-fold by this drug. Indinavir-induced mRNA changes and SREBP-1 mature protein levels were significantly abated by the addition of cholesterol, solubilized in β-cyclodextrin, to culture medium. Indinavir markedly decreased endogenous cholesterol esterification and increased cholesterol in intracellular membranes in primary hepatocytes. Indinavir gavaged into intact mice also markedly increased SREBP-1 and SREBP-2 (mature forms) in hepatic nuclei. CYP7A1 mRNA was also decreased ∼52% in indinavir-treated animals. We propose that indinavir disrupts cellular cholesterol homeostasis by increasing SREBP’s and decreasing CYP7A1 mRNA. [Copyright &y& Elsevier]

Examines the role of toxic bile saltiinduced apoptosis of hepatocytes in human cholestatic liver diseases. Effects of the accumulation of high concentrations of toxic, hydrophobic bile salts within hepatocytes during cholestasis; Information on the effects of bile salt.

Examines the bile acids activation of hepatocellular protein kinase C (PKC) that regulate cholesterol 7alpha-hydroxylase. Repression of cholesterol 7alpha-hydroxylase transcription; PKC's dependence of negative bile acid biofeedback on bile acid hydrophobicity; Site of bile acid biosynthesis.

Investigates the involvement of protein kinase C (PKC) in bile salt-induced apoptosis of hepatocytes. Effects of PKC inhibitors on glycochenodeoxycholate (GCDC)-induced apoptosis; PKC and phosphatase activity in GCDC-induced apoptosis; Translocation of PKC isoforms during GCDC-induced apoptosis.

Investigates the mechanism by which bile acids activate hepatic protein kinase C (PKC) activity and the consequences of this activation on isoform distribution and cholesterol 7alpha-hydroxylase messenger ribonucleic acid levels. Identification and resting distribution of PKC isoforms in rat liver and cultured rat hepatocytes; Direct activation of PKC in vitro.

The characteristics of hybrid three-arm coupler, which consists of the middle long range surface plasmon polariton waveguide and two outside conventional dielectric waveguides, are analyzed numerically with finite element method. Since the middle arm can only transfer the TM mode from one dielectric arm to the other one, this structure is promising for realizing integrated polarization splitter. Compared with the two-arm hybrid coupler, the loss of three-arm hybrid coupler based device can be reduced. Furthermore, different from conventional three-arm dielectric coupler, the authors find that the three-arm hybrid coupler with asymmetric structure can reach a much higher extinction ratio. [ABSTRACT FROM AUTHOR]

Coupling of TM mode between long range surface plasmon polariton (LRSPP) mode and conventional dielectric waveguide mode is demonstrated numerically with finite element method. The characteristics of a hybrid coupler, which consists of the LRSPP waveguide and conventional single mode dielectric waveguide, are analyzed. The high efficient coupling shows a possible route for integrating the SPP device and conventional dielectric optical devices together and a method to excite LRSPP mode with dielectric waveguide. Because the coupling just occurs on TM mode, this kind of the hybrid coupler can be used as polarization mode splitter and combiner. [ABSTRACT FROM AUTHOR]

Cites the results of the study of K. Letinic and P. Rakic reporting the first direct evidence that neurons migrate from the ganglionic eminence (GE) to the dorsal thalamus (DT) in human brain tissues. GABA contained in the migrating neurons; Non-detection of cell migration from the GE to the DT in the monkey or mouse brains; Involvement of the neuronal migration in brain evolution.

Face recognition is important for both visual and social cognition. While prosopagnosia or face blindness has been known for seven decades and face-specific neurons for half a century, the molecular genetic mechanism is not clear. Here we report results after 17 years of research with classic genetics and modern genomics. From a large family with 18 congenital prosopagnosia (CP) members with obvious difficulties in face recognition in daily life, we uncovered a fully cosegregating private mutation in the MCTP2 gene which encodes a calcium binding transmembrane protein expressed in the brain. After screening through cohorts of 6589, we found more CPs and their families, allowing detection of more CP associated mutations in MCTP2. Face recognition differences were detected between 14 carriers with the frameshift mutation S80fs in MCTP2 and 19 noncarrying volunteers. Six families including one with 10 members showed the S80fs-CP correlation. Functional magnetic resonance imaging found association of impaired recognition of individual faces by MCTP2 mutant CPs with reduced repetition suppression to repeated facial identities in the right fusiform face area. Our results have revealed genetic predisposition of MCTP2 mutations in CP, 76 years after the initial report of prosopagnosia and 47 years after the report of the first CP. This is the first time a gene required for a higher form of visual social cognition was found in humans. [ABSTRACT FROM AUTHOR]

Diatoms have unique silica cellular and metabolic characteristics and can grow in various environments, including wastewater, facilitating pollutant removal. Diatoms provide a sustainable solution to municipal wastewater treatment, particularly in the tertiary and quaternary stages, contributing to carbon neutrality. Diatom-based materials (such as diatom biomass) have wide applications and can be processed into value-added bioproducts such as lipids, polysaccharides, and pigments. Despite their potentials, the applications of diatoms in wastewater treatment are limited. Existing reviews fail to address how diatom growth kinetics affects wastewater treatment. Here, we for the first time summarize diatom growth kinetics and propose promising species for municipal wastewater treatment. Given the scarcity of reviews on diatom performance in wastewater treatment, we also discuss the efficacy of diatoms in removing contaminants from municipal wastewater. Moreover, we elucidate the removal mechanisms of nutrients, heavy metals, and emerging contaminants by diatoms that are missing in existing reviews. Considering the complexity of wastewater, we emphasize selecting diatom species with high growth rates, tolerance to contaminants, efficient nutrient removal/uptake, and COD removal, and bioproduct yields. This will ensure both effective treatment and economic viability. In addition, we discuss the value of diatom frustules and bioproducts generated from wastewater. Lastly, we highlight future directions including promoting diatom growth, exploring diatom-dominated consortia in wastewater treatment, and evaluating the values of diatom biomass cultivated in wastewater. This review examines the potential and applications of diatoms in municipal wastewater treatment, especially effluent polishing. Diatoms are a sustainable solution to municipal wastewater treatment Diatoms can remove nutrients, heavy metals, and emerging pollutants from wastewater Summarized the growth kinetics of various diatom species for the first time Discussed the removal mechanisms of contaminants from wastewater by diatoms Compiled the wide applications of diatom biomass from wastewater [ABSTRACT FROM AUTHOR]

Inorganic CsPbI3 perovskite with an optical bandgap ranging from 1.67 to 1.75 eV is a promising light‐harvesting material as a top cell in tandem solar cells, but its high fabrication temperature can damage the middle layers or the bottom subcells. Here, an additive‐involved leaching method to fabricate CsPbI3 perovskite films is demonstrated, which can decrease the preparation temperature to 100 °C. The CsPbI3 perovskite films with high crystallinity are achieved by a solution assisted reaction between DMAPbI3 and Cs4PbI6 with the leaching of DMA+, Cs+, and I−. The as‐prepared CsPbI3 perovskite films exhibit much superior stability compared to their high‐temperature counterparts. As a result, a power conversion efficiency of over 16% is obtained, and the unencapsulated device maintains over 93% of the initial efficiency after aging for 30 days in air with a relative humidity of 10%. [ABSTRACT FROM AUTHOR]

Inorganic CsPbI3 perovskite with an optical bandgap ranging from 1.67 to 1.75 eV is a promising light‐harvesting material as a top cell in tandem solar cells, but its high fabrication temperature can damage the middle layers or the bottom subcells. Here, an additive‐involved leaching method to fabricate CsPbI3 perovskite films is demonstrated, which can decrease the preparation temperature to 100 °C. The CsPbI3 perovskite films with high crystallinity are achieved by a solution assisted reaction between DMAPbI3 and Cs4PbI6 with the leaching of DMA+, Cs+, and I−. The as‐prepared CsPbI3 perovskite films exhibit much superior stability compared to their high‐temperature counterparts. As a result, a power conversion efficiency of over 16% is obtained, and the unencapsulated device maintains over 93% of the initial efficiency after aging for 30 days in air with a relative humidity of 10%. [ABSTRACT FROM AUTHOR]

The lifetime for injecting hot electrons generated in Ag nanoplatelets to nearby TiO2 nanorods was measured with ultrafast transient IR absorption to be 13.1 ± 1.5 fs, which is comparable to values previously reported for much smaller spherical Ag nanoparticles. Although it was shown that the injection rate decreases as the particle size increases, this observation can be explained by the facts that (1) the platelet has a much larger surface to bulk ratio and (2) the platelet affords a much larger surface area for direct contact with the semiconductor. These two factors facilitate strong Ag–TiO2 coupling (as indicated by the observed broadened surface plasmon resonance band of Ag) and can explain why Ag nanoplatelets have been found to be more efficient than much smaller Ag nanoparticles as photosensitizers for photocatalytic functions. The fast injection rate, together with a stronger optical absorption in comparison with Au and dye molecules, make Ag nanoplatelets a preferred photosensitizer for wide bandgap semiconductors. [ABSTRACT FROM AUTHOR]

Soybean meal is commonly applied as the raw material in the bio-fermentation industry, and bacitracin is a widely used feed additive in the feed industry. In this study, we investigated the influence of subtilisin enhancement on soybean meal utilization and bacitracin production in Bacillus licheniformis DW2, an industrial strain for bacitracin production. Firstly, blocking sRNA aprA expression benefited bacitracin synthesis, and the bacitracin yield produced by aprA-deficient strain DW2△PaprA reached 931.43 U/mL, 18.92% higher than that of DW2 (783.25 U/mL). The bacitracin yield was reduced by 14.27% in the aprA overexpression strain. Furthermore, our results showed that deficiency of aprA led to a 6.54-fold increase of the aprE transcriptional level and a 1.84-fold increase of subtilisin activity, respectively, which led to the increases of soybean meal utilization rate (28.86%) and precursor amino acid supplies for bacitracin synthesis. Additionally, strengthening the utilization rate of soybean meal also benefited heterologous protein production, and the α-amylase and nattokinase activities were respectively enhanced by 59.81% and 50.53% in aprA-deficient strains. Collectively, this research demonstrated that strengthening subtilisin production could improve the utilization rate of soybean meal and thereby enhance bacitracin and target protein production; also, this strategy would be useful for the improvement of protein/peptide production using soybean meal as the main nitrogen source in the fermentation process. [ABSTRACT FROM AUTHOR]

This study explores the chemical bonding patterns of homoatomic and heteroatomic lead anion clusters using the Adaptive Natural Density Partitioning (AdNDP) algorithm. The findings reveal the presence of multiple delocalized bonds and the classification of these clusters as aromatic compounds. [Display omitted] Lead anion clusters, as examples of Zintl anions, have captivated researchers due to their intriguing structures and unexpected stoichiometries. Despite extensive experimental and theoretical investigations, the understanding of the chemical bonding in these clusters remains incomplete and subject to interpretation. In this study, we focused on several widely studied homoatomic and heteroatomic lead anionic clusters and employed the Adaptive Natural Density Partitioning (AdNDP) algorithm to decipher their bonding patterns. Our aim was to provide chemically intuitive descriptions of the bonding in these clusters. Our findings reveal the presence of multiple delocalized bonds in most of the studied lead clusters. Remarkably, these bonding patterns exhibit characteristics of aromatic compounds. This work represents a step towards a more comprehensive understanding of the bonding in lead anion clusters. By shedding light on their chemical bonding patterns, we hope to inspire further research in the design and synthesis of novel lead homoatomic and heteroatomic Zintl clusters, fostering advancements in their properties and potential applications. [ABSTRACT FROM AUTHOR]

High-performance electromagnetic wave absorption materials constitute key components of microelectronic devices. Traditional absorbents possess magnetic losses and/or dielectric losses, while the experimental approach for their simultaneous enhancement is still lacking. Here, we demonstrate that the core/shell structural Ni@C nanocapsules, functionalized by atomic-scale oxygen substitutions that can be formed catalytically by highly defective graphitic structure, present enhanced dielectric loss capacities at gigahertz. In particular, >90% of the microwave energy could be attenuated for a planar absorber with a thickness down to 1–1.5 mm at 7.6–13.8 GHz. Experimental characterizations coupled with density functional theory calculations further evidence that the capacity enhancement is ascribed to the structure breaking at the heterogeneous substitutional zones, resulting in the intrinsic polarization of carbon–oxygen heterostructures. The present study shows a new mentality of designing for optimizing electromagnetic wave absorption materials and also has pointed out the atomic-scale structural origin of the electromagnetic response performance. [ABSTRACT FROM AUTHOR]