IVSPlat 1.0: an integrated virtual screening platform with a molecular graphical interface

Background  

The virtual screening (VS) of lead compounds using molecular docking and pharmacophore detection is now an important tool in drug discovery. VS tasks typically require a combination of several software tools and a molecular graphics system. Thus, the integration of all the requisite tools in a single operating environment could reduce the complexity of running VS experiments. However, only a few freely available integrated software platforms have been developed.     

Construction of aromatic [5,5] spiroketals via hypoiodite-catalyzed etherification combined in relay cascades

An approach is developed for the synthesis of bisbenzannelated spiro[5,5]ketals via a catalytic relay reaction cascade involving a new cyclo-etherification, which is prompted by fluoride and catalyzed by the hypoiodite species generated in situ from irradiative aerobic oxidation of an iodide ion formed in the former step of the reaction cascade.     

3D-structured carbon-coated MnO/graphene nanocomposites with exceptional electrochemical performance for Li-ion battery anodes

MnO has a high theoretical capacity, moderate discharge plateau, and low polarization when it is used as the anode material in lithium battery. However, the issues that limit its application are its poor conductivity and large volume changes, which can easily result in the collapse of electrode structure during long-term cycling. In the present work, a carbon-coated MnO/graphene 3D-network anode material is synthesized by an electrostatic adsorption of dispersed precipitates precipitation method. The MnO nanoparticles coated by carbon are uniformly distributed on the surface of graphene nanosheets and form a 3D sandwich-like nanostructure. A carbon layer is coated on the surface of MnO nanoparticles, which slows down the volume expansion in the process of lithium intercalation. The graphene nanosheets are cross-linked through carbons in this 3D nanostructure, which provides mechanical support and effective electron conduction pathways during the charge-discharge. The electrochemical tests indicate that the prepared 3D carbon-coated MnO/graphene electrode exhibits an excellent rate capacity of 1247.3 and 713.2 mAh g^?1 at 100 and 1000 mA g^?1, respectively. The capacity is 792.2 mAh g^?1 after long cycle at a current density of 1000 mA g^?1. The specific capacity is higher than that of MnO-based composite lithium anode materials currently reported. The superior rate and cycling performances are attributed to the unique 3D-network structure, which provides an effectively conductive network, buffers volume expansion, and prevents falling and aggregation of MnO in the charge and discharge process of the electrode materials. The 3D-structured carbon-coated MnO/graphene anode material will have an excellent application prospect.

Open image in new window

Graphical abstract Cyclic performance at 1 A g^?1 and SEM images (inset) of the 3D-structured carbon-coated MnO/graphene nanocomposite.

     

Dynamic modeling and simulation of deploying process for space solar power satellite receiver

To reveal some dynamic properties of the deploying process for the solar power satellite via an arbitrarily large phased array (SPS-ALPHA) solar receiver, the symplectic Runge-Kuttamethod is used to simulate the simplified model with the consideration of the Rayleigh damping effect. The system containing the Rayleigh damping can be separated and transformed into the equivalent nondamping system formally to insure the application condition of the symplectic Runge-Kutta method©First, the Lagrange equation with the Rayleigh damping governing the motion of the system is derived via the variational principle. Then, with some reasonable assumptions on the relations among the damping, mass, and stiffness matrices, the Rayleigh damping system is equivalently converted into the nondamping system formally, so that the symplectic Runge-Kutta method can be used to simulate the deploying process for the solar receiver. Finally, some numerical results of the symplectic Runge-Kutta method for the dynamic properties of the solar receiver are reported. The numerical results show that the proposed simplified model is valid for the deploying process for the SPS-ALPHA solar receiver, and the symplectic Runge-Kutta method can preserve the displacement constraints of the system well with excellent long-time numerical stability.     

TRIM45 causes neuronal damage by aggravating microglia-mediated neuroinflammation upon cerebral ischemia and reperfusion injury

Excessive and unresolved neuroinflammation is a key component of the pathological cascade in brain injuries such as ischemic stroke. Tripartite motif-containing 45 (TRIM45) is a ubiquitin E3 ligase involved in various critical biological processes. However, the role of TRIM45 in cerebral ischemia remains unknown. Here, we found that the TRIM45 protein was highly expressed in the peri-infarct areas of mice subjected to cerebral ischemia and reperfusion injury induced by middle cerebral artery occlusion. This study systemically evaluated the putative role of TRIM45 in the regulation of neuroinflammation during ischemic injury and the potential underlying mechanisms. We found that TRIM45 knockdown significantly decreased proinflammatory cytokine and chemokine production in primary cultured microglia challenged with oxygen-glucose deprivation and reoxygenation (OGD/R) treatment. Mechanistically, we demonstrated that TRIM45 constitutively interacted with TAB2 and consequently facilitated the Lys-63-linked polyubiquitination of TAB2, leading to the formation of the TAB1–TAK1–TAB2 complex and activation of TAK1, which was ultimately followed by activation of the nuclear factor-kappa B (NF-κB) signaling pathway. In an in vitro coculture Transwell system, downregulation of TRIM45 expression also inhibited the OGD/R-induced activation of microglia and alleviated neuronal apoptosis. More importantly, microglia-specific knockdown of TRIM45 in mice significantly reduced the infarct size, mitigated neurological deficit scores, and improved cognitive function after ischemic stroke. Taken together, our study reveals that the TRIM45–TAB2 axis is a crucial checkpoint that controls NF-κB signaling in microglia during cerebral ischemia and reperfusion injury. Therefore, targeting TRIM45 may be an attractive therapeutic strategy.Subject terms: Cell death in the nervous system, Stroke     

Study on the composite Nd：YAG crystal by laser micro- Raman spectroscopy

The composite Nd:YAG crystal with undoped YAG end caps was fabricated by thermal bonding technique. Scanning electron microscopy (SEM) result shows that the width of the bonded interface was about 0.5 μm. The laser micro-Raman was used to study the bonded interface of the composite crystal. The results of Raman spectra and the bonded interface image indicate that the undoped YAG and Nd:YAG crystals have been well bonded together. Furthermore, it can be drawn that the structure and the composition of the bonded interface are the same as the undoped YAG crystal, and that the Nd3 ions do not enter the bonded interface and the YAG side. This property is advantageous to decrease the thermal effect of the boned interface and to improve the laser stability.     

Experimental synchronization of independent entangled photon sources

We report the generation of independent entangled photon pairs from two synchronized but mutually incoherent laser sources. The quality of synchronization is confirmed by observing a violation of Bell's inequality with 3.2 standard deviations in an entanglement swapping experiment. The techniques developed in our experiment are not only important for realistic linear optical quantum-information processing, but also enable new tests of local realism.     

Ultrasonic treatment on activated sewage sludge from petro-plant for reduction

In this essay, the influences of low frequency ultrasound (20 kHz) on dewater ability and anaerobic digestion behaviors of activated sewage sludge, obtained from Yangzi Water Treatment Plant, Yangzi Petrochemical Corporation, were discussed. Ultrasound pretreatment could enhance the filtration progress and decrease the moisture content of the sludge from 99% to 80%. Together with flocculant, the ultrasound pretreatment decreased the specific filtration resistance (SFR) of the sludge from 3.59 x 10(12) m/kg to 1.18 x 10(12) m/kg and saved about 25-50% of the flocculant dosage. Bound water of the sludge was measured by dilatometer. After 2-4 min treatment of ultrasound under intensity of 400 W/m(2), the bound water of sludge decreased from 16.7 g/g (dry base) to above 2.0 g/g (dry base). Ultrasound pretreatment could also enhance digestion and reduce digestion time. To the same resolution ratio, such as 49%, the digestion time of sludge with ultrasound pretreatment was 7 days less than that without ultrasound. Proper ultrasound pretreatment could also improve the dewater ability of the digested sludge, the final moisture of which was 73.7%.     

Development of novel flexible black silicon

We report a new type of black silicon: flexible black silicon. A silicon-on-insulator (SOI) wafer is irradiated by automatically scanning a femtosecond laser and then split by etching out the SOI silica middle layer. Large-area, uniform micro spikes on the surface of a very thin flexible silicon layer are obtained. The black silicon shows good flexibility and optical properties. The absorption spectrum of the flexible black silicon is as high as 97% in the visible and insensitive to the change of the incident angle of the light, which makes it a potential good candidate as an absorber for the solar-thermo generator.     

Propagation characteristics of annular laser beams passing through the reflection Bragg grating with deformation

When high-power annular laser beams produced by the unstable resonator pass through the volume Bragg grating (VBG), absorption of light in the VBG will induce a temperature increment, resulting in changes in surface distortion. Considering that the surface distortion of the grating induces index and period differences, the scalar wave equations for the annular laser beams propagating in the VBG have been solved numerically and iteratively using finite-difference and sparse matrix methods. The variation in intensity distributions, the total power reflection coefficient, and the power in the bucket (PIB) for the annular laser beams passing through the reflection VBG with deformation have been analyzed quantitatively. It can be shown that the surface distortion of the VBG and the beam orders of the annular beams affect evidently the intensity distributions, the power reflection coefficient, and the PIB of the output beam. The peak intensity decreases as the deformation of the VBG increases. The total power reflection efficiency decreases significantly with the increase in deformations of the VBG. The PIB of the output beam decreases as the obscuration ratio β and the deformation of the VBG increase. For the given obscuration ratio β, the influence of deformation of reflection VBG on the PIB of the annular beams is more sensitive with increase in distortion of the VBG and decrease in beam order.