Some combinatorial properties of hexagonal lattices

In this paper, we consider the combinatorial properties of the hexagonal lattice. Let $e(n)$ be the number of $n$-element order ideals in a hexagonal lattice. We give the enumeration of $e(n)$ by showing a bijection between the order ideals and Schröder paths. Further, we get formulae for the flag $f$- and $h$-vectors of the hexagonal lattice

Virtual Reference for Video Collections: System Infrastructure, User Interface and Pilot User Study

A new video-based Virtual Reference (VR) tool called VideoHelp was designed and developed to support video navigation escorting, a function that enables librarians to co-navigate a digital video with patrons in the web-based environment. A client/server infrastructure was adopted for the VideoHelp system and timestamps were used to achieve the video synchronization between the librarians and patrons. A pilot usability study of using VideoHelp prototype in video seeking was conducted and the preliminary results demonstrated that the system is easy to learn and use, and real-time assistance from virtual librarians in video navigation is desirable on a conditional basis

Supersolvability and Freeness for ψ-Graphical Arrangements

Let G be a simple graph on the vertex set {v[subscript 1],…,v[subscript n]} with edge set E. Let K be a field. The graphical arrangement A[subscript G] in K[superscript n] is the arrangement x[subscript i]−x[subscript j]=0,v[subscript i]v[subscript j] ∈ E. An arrangement A is supersolvable if the intersection lattice L(c(A)) of the cone c(A) contains a maximal chain of modular elements. The second author has shown that a graphical arrangement A[subscript G] is supersolvable if and only if G is a chordal graph. He later considered a generalization of graphical arrangements which are called ψ-graphical arrangements. He conjectured a characterization of the supersolvability and freeness (in the sense of Terao) of a ψ-graphical arrangement. We provide a proof of the first conjecture and state some conditions on free ψ-graphical arrangements.China Scholarship CouncilNational Science Foundation (U.S.) (Grant DMS-1068625

Virtual Reference for Video Collections: System Infrastructure, User Interface and Pilot User Study

A new video-based Virtual Reference (VR) tool called VideoHelp was designed and developed to support video navigation escorting, a function that enables librarians to co-navigate a digital video with patrons in the web-based environment. A client/server infrastructure was adopted for the VideoHelp system and timestamps were used to achieve the video synchronization between the librarians and patrons. A pilot usability study of using VideoHelp prototype in video seeking was conducted and the preliminary results demonstrated that the system is easy to learn and use, and real-time assistance from virtual librarians in video navigation is desirable on a conditional basis

Transgenic Potato with Resistant to PVX，PVY and PSTVd Simultaneously by amiRNA-mediated and Resistance Evaluation

peer reviewedIn order to obtain potato plants which could be resistant to multiple viruses ( viroid) simultaneous- ly，P25，HC-Pro，and Virp1 gene targeting PVX，PVY，and PSTVd proteins were cloned，respectively. Three types of amiRNAs targeting sequences encoding the silencing suppressor P25，HC-Pro and Virp1 were designed by using Ar- abidopsis thaliana miR159a as backbone. These three amiRNA sequences were connected by Overlapping PCR. The synthetic of P25，HC-Pro and Virp1 gene was inserted into the expression vector pCAMBIA1300-221 to form p1300-221-preamiR-P25-HCPro-Virp1，and the vector was verified by PCR and restriction enzyme digestion. Pre-a- miR-P25-HCPro-Virp1 was transformed into minituber of potato cultivar Favorita by Agrobacterium tumefaciens in- fection. 15 transformed plants were obtained through regenerating，pressure screening and differentiation. PCR re- sults showed that 10 of them were detected the same size fragment ( 729 bp) as the target gene. Further qRT-PCR t e s t i n g c o n f i r m e d t h a t a m i R - P 2 5 - H C P r o - V i r p 1 g e n e w a s e x p r e s s e d i n 1 0 t r a n s f o r m e d p l a n t s ，a n d t h e r e l a t i v e e x p r e s - sion was between 7. 68 - 21. 37. Inoculated the T0 transgenic plants with the mixture virus of PVX，PVY and PSTVd by friction into the leaves of the plants at the 6 - 8 leaf stage. The plant growth was observed after 20 days and the results showed that the control plants were severely susceptible，with symptoms such as short plants and mottled leaves，while the transformed plants did not show infection symptoms，and growth normally. There was no vi- rus detected by RT-PCR either. This indicated that the transfected amiR-P25-HCPro-Virp could be stably expressed in the transformed plants，and the transformed plants were resistant to PVX，PVY and PVSTd viruses ( viroid) . Transformed plants resistant to PVX，PVY and PVSTd were obtained，and the resistance was significant，which pro- vided new genetic resources for potato virus-resistant breeding

Effects of Thinning Intensities on Soil Infiltration and Water Storage Capacity in a Chinese Pine-Oak Mixed Forest

Thinning is a crucial practice in the forest ecosystem management. The soil infiltration rate and water storage capacity of pine-oak mixed forest under three different thinning intensity treatments (15%, 30%, and 60%) were studied in Qinling Mountains of China. The thinning operations had a significant influence on soil infiltration rate and water storage capacity. The soil infiltration rate and water storage capacity in different thinning treatments followed the order of control (nonthinning): <60%, <15%, and <30%. It demonstrated that thinning operation with 30% intensity can substantially improve soil infiltration rate and water storage capacity of pine-oak mixed forest in Qinling Mountains. The soil initial infiltration rate, stable infiltration rate, and average infiltration rate in thinning 30% treatment were significantly increased by 21.1%, 104.6%, and 60.9%, compared with the control. The soil maximal water storage capacity and noncapillary water storage capacity in thinning 30% treatment were significantly improved by 20.1% and 34.3% in contrast to the control. The soil infiltration rate and water storage capacity were significantly higher in the surface layer (0~20 cm) than in the deep layers (20~40 cm and 40~60 cm). We found that the soil property was closely related to soil infiltration rate and water storage capacity