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As the extension of traditional linear (or X) inverted pendulum (IP), X-Z IP is a multiple-input multiple-output (MIMO), underactuated, open-loop unstable, and nonlinear system. In the tracking control of the X-Z IP, the equilibrium point changes with the pivot position of the pendulum. This makes linear control theories have difficulties in realization of the tracking control for the pendulum. The underactuated feature of the pendulum makes the feedback linearization unsuitable to simplify the control design. With the present model of the X-Z IP, there is no way to realize the backstepping design. This paper gives a novel state transformation method for the X-Z IP. Through the state transformation, the block backstepping can be easily deployed in the controller design of the X-Z IP. The proposed controller can achieve the tracking control in the vertical plane. Simulation results certify the rightness and effectiveness of the proposed tracking controller.

Background Aphids are important vectors of numerous plant viruses. Besides plant viruses, a number of insect specific viruses (ISVs), such as nege/nege-like viruses, have been recently discovered in aphids of the genera Aphis, Rhopalosiphum, and Sitobion. Findings In this study, the complete genome sequence of a novel nege-like virus, tentatively named “Indomegoura nege-like virus 1” (INLV1), was identified in aphids of the genus Indomegoura. INLV1 possessed a single positive-stranded RNA genome with 8945 nucleotides, which was predicted to contain three typical open reading frames (ORFs) of negeviruses (including ORF1, ORF2, and ORF3), a 44-nt 5′ untranslated region (UTR) and a 98-nt 3′ UTR. Five conserved domains were predicted for INLV1, including an Alphavirus-like methyltransferase domain, a RNA virus helicase core domain, and a RNA-dependent RNA polymerase domain (RdRP) in ORF1, a DISB-ORF2_chro domain in ORF2, and a SP24 domain in ORF3. According to the maximum likelihood phylogenetic tree based on RdRP, INLV1 was grouped with barley aphid RNA virus 1 and Hubei virga-like virus 4, together with another two invertebrate viruses, which formed a distinct clade in the proposed group Centivirus. The alignment of RdRP domains for INLV1 and other nege/kita-like viruses suggested that RdRP of INLV1 contained the permuted C (GDD)- A [DX(4–5)D] –B [GX(2–3)TX(3)N] motifs, which were conserved in the Centivirus and Sandewavirus groups. Furthermore, the high abundance and typical characteristics of INLV1 derived small interfering RNAs clearly showed the active replication of INLV1 in the aphid Indomegoura. Conclusion INLV1 is the first nege-like virus infecting aphids of the genus Indomegoura. As far as we know, it is also the first ISV revealed in this aphid genus.

Effect of laser scanning pitch on micro-holes drilling of silicon nitride (Si3N4) ceramics was investigated in this study. Results showed that laser scanning pitch had a significant influence on the geometry of holes. For instance, the taper angles of holes increased with the increase in scanning pitch. Measurement data also showed that the diameters and circularity decreased with the increase in scanning pitch at the both entrance and exit sides. It was also noted that the change of scanning pitch had little effect on the dimensions of holes at the entrance side. The elemental composition was closely related to the distance from the edge of the hole due to the chemical reaction of laser machining in air. The surface toughness increased with the increase in scanning pitch. The present study suggested that the higher processing quality of holes could be achieved at the smaller scanning pitch.

Nanosecond pulsed laser drilling of silicon nitride ceramic was conducted in air and under water to study the effects of laser scanning speed and processing environment on the hole taper. Results showed that drilling under water has a more profound impact to the hole taper than in air. The shape of cross-section was significantly different between two processing environments. In order to describe the curve shape under water, a novel characterization method was thus proposed to calculate taper angle as a function of the depth of holes. The taper angles decreased with increasing depth of holes at the fixed scanning speed and the similar tendency was also observed with decreasing scanning speed at the same depth of holes. The differences of element composition and surface roughness between air and under water were investigated. The present results suggested the better processing surface quality could be obtained by laser drilling under water.

Five new pregnane glycosides, sinomarinosides A (1), B (2), C (3), D (4), and E (5), have been isolated from Sinomarsdenia incisa (Asclepiadaceae). The structures of these compounds were elucidated by NMR and mass spectroscopic methods and chemical evidence.

Reinvestigation of the NMR spectra of gymnemarsgenin by the selective INEPT and various two-dimensional NMR techniques (DQF-COSY, ROESY, HETCOR) led to the structural revision of gymnemarsgenin as 12 β - O -cinnamoyl-20- O -benzoyl sarcostin. The 1 H and 13 C NMR spectra were completely assigned. It is apparent that the 12-cinnamoyl group migrated to C-20 under the mild alkaline conditions rendered for partial saponification.

Dimercaptosuccinic acid (DMSA) modified ultra-small particles of iron oxide (USPIO) were synthesized through a two-step process. The first step: oleic acid (OA) capped Fe(3)O(4) (OA-USPIO) were synthesized by a novel oxidation coprecipitation method in H(2)O/DMSO mixing system, where DMSO acts as an oxidant simultaneously. The second step: OA was replaced by DMSA to obtain water-soluble nanoparticles. The as-synthesized nanoparticles were characterized by TEM, FTIR, TGA, VSM, DLS, EDS and UV-vis. Hydrodynamic sizes and Peroxidase-like catalytic activity of the nanoparticles were investigated. The hydrodynamic sizes of the nanoparticles (around 24.4 nm) were well suited to developing stable nanoprobes for bio-detection. The kinetic studies were performed to quantitatively evaluate the catalytic ability of the peroxidase-like nanoparticles. The calculated kinetic parameters indicated that the DMSA-USPIO possesses high catalytic activity. Based on the high activity, immunohistochemical experiments were established: using low-cost nanoparticles as the enzyme instead of expensive HRP, Nimotuzumab was conjugated onto the surface of the nanoparticles to construct a kind of ultra-small nanoprobe which was employed to detect epidermal growth factor receptor (EGFR) over-expressed on the membrane of esophageal cancer cell. The proper sizes of the probes and the result of membranous immunohistochemical staining suggest that the probes can be served as a useful diagnostic reagent for bio-detection.

Reinvestigation of the NMR spectra of gymnemarsgenin by the selective INEPT and various two-dimensional NMR techniques (DQF-COSY, ROESY, HETCOR) led to the structural revision of gymnemarsgenin as 12 β - O -cinnamoyl-20- O -benzoyl sarcostin. The 1 H and 13 C NMR spectra were completely assigned. It is apparent that the 12-cinnamoyl group migrated to C-20 under the mild alkaline conditions rendered for partial saponification.

Two new glycosides named cynanversicoside-A and -B, together with glaucogenin-C as the aglycone, were isolated from the Chinese crude drug "Pai-Wei", CYNANCHUM VERSICOLOR Bunge (Asclepiadaceae). Their structures were determined on the basis of spectral and chemical evidence as glaucogenin-C 3- O-beta- D-cymaropyranosyl-(1-->4)-alpha- L-diginopyranosyl-(1-->4)-beta- D-thevetopyranoside and glaucogenin-C 3- O-beta- D-glucopyranosyl-(1-->4)-beta- D-cymaropyranosyl-(1-->4)-alpha- L-diginopyranosyl-(1-->4)-beta- D-thevetopyranoside.

The glycoside portions of the Chinese crude “Pai-Wei’, dried root of Cynanchum atratum have been investigated. Four new glycosides named atratosides A–D of which the aglycones were novel 14,15-seco-pregnanes, were isolated and their structures were determined on the basis of spectroscopic evidence and analyses of their hydrolysates as atratogenin A 3-O-β- d -cymaropyranosyl-(1 →4)-α- l -diginopyranosyl-(1 →4)-β- d - cymaropyranoside, atratogenin A 3-O-β- d -glueopyranosyl-(1 →4)-β- d -cymaropyranosyl- (1 →4)-α- l -diginopyranosyl-(1 →4)-β- d -cymaropyranoside, atratogenin B 3-O- β- d -glucopyranosyl-(1 →4)-β- d -cymaropyranosyl-(1 →4)-α- l -diginopyranosyl (1 →4)-β- d -cymaropyranoside, and cynajapogenin A α- d -oleandropyranosyl-(1 →4)- β- d -digitoxopyranosyl-(1 →4)β- d -cymaropyranoside.

Three new glycosides named cynaversicoside C, D and E with glaucogenin D as the aglycone were isolated from the Chinese crude drug ‘Pai-Wei’, Cynanchum versicolor . Their structures were determined on the bases of combined physio-chemical evidence as glaucogenin D:3- O -β- d -thevetopyranoside; glaucogenin D:3- O -β- d -cymaropyranosyl-(1→4)-α- l -diginopyranosyl-(1→4)-β- d -thevetopyranoside; glaucogenin D:3- O -β-glucopyranosyl-(1→4)-β- d -cymaropyranosyl-(1→4)-α- l -diginopyranosyl-(1→4)-β- d -thevetopyranoside.

The chemical components of the Chinese crude drug "Pai-Wei, " dried root of Cynanchum atratum BUNGE (Asclepiadaceae), have been studied. Five new oligoglycosides named cynatratoside-A (3), -B (4), -C (6), -D (8), and -E (9) were isolated by column chromatography and their structures were determined on the basis of chemical and spectral evidence.