Adaptive window space direction laser speckle contrast imaging to improve vascular visualization.

Vascular visualization is crucial in monitoring, diagnosing, and treating vascular diseases. Laser speckle contrast imaging (LSCI) is widely used for imaging blood flow in shallow or exposed vessels. However, traditional contrast computation using a fixed-sized sliding window introduces noise. In this paper, we propose dividing the laser speckle contrast image into regions and using the variance criterion to extract pixels more suitable for the corresponding regions for calculation, and changing the shape and size of the analysis window at the vascular boundary regions. Our results show that this method has a higher noise reduction and better image quality in deeper vessel imaging, revealing more microvascular structure information.

DFT study on the structures and properties of 3-nitro-1,2,4-triazol-5-one crystals at high pressure.

The geometries, lattice parameters, electronic structures, XRD spectra and optical properties of the 3-nitro-1,2,4-triazol-5-one (NTO) crystals at high pressure (2, 4, 6, 8 and 10GPa) have been studied using density functional theory within the generalized gradient approximation implemented using ultrasoft pseudo-potentials. The computational results show that with increasing pressure, the NTO lattice parameters and hydrogen bonds lengths rapidly decrease and the geometries change very little. The total energy increases by approximately 27.543eV from 0 to 10GPa. NTO becomes increasingly conductive or metallic with increasing pressure, while the XRD peaks are shifted to greater angles and the absorption coefficient alpha(omega) increases.

Poly[diaquacobalt(II)-di-mu4-benzene-1,2,4-tricarboxylato-bis[1,10-phenanthrolinecobalt(II)]].

In the polymeric title compound, [Co(3)(btc)(2)(phen)(2)(H(2)O)(2)](n) [btc is the benzene-1,2,4-tricarboxylate trianion (C(9)H(3)O(6)) and phen is 1,10-phenanthroline (C(12)H(8)N(2))], there are two different Co centres, Co1 and Co2. The Co1 centre has a deformed trigonal-bipyramidal geometry, while the Co2 centre lies on an inversion centre and has distorted octahedral geometry. Moreover, the 1,2-dicarboxylate groups of one btc ligand bridge the two adjacent Co2 centres, and each Co2 centre is coordinated by four carboxylate O atoms from four different btc ligands, forming a novel kind of intersecting double-chain structure, with a Co.Co separation of 7.755 A, along the a axis. On the other hand, the two Co1 centres are bridged by two btc ligands and chelated by phen molecules, respectively, producing a binuclear unit with a Co.Co separation of 8.406 A, and these binuclear units are linked by btc bridges and Co2 centres to extend hybrid chains of Co1 and Co2 along the [101] direction. Furthermore, each btc ligand acts as a pentadentate bridge, linking the Co2 double-chain structures and the hybrid chains of Co1 and Co2 to yield a two-dimensional network, and this leads to the formation of very different kinds of voids.

Catena-poly[bis[(2,2-bipyridine-kappa2N,N')copper(II)]-mu4-1,2,4,5-benzenetetracarboxylato-kappa4O1:O2:O3:O4].

In the title complex, [Cu(2)(C(10)H(2)O(8))(C(10)H(8)N(2))(2)](n), the Cu(II) cation has a four-coordinated environment, completed by two carboxyl O atoms belonging to two 1,2,4,5-benzenetetracarboxylate anions (TCB(4-)) and two N atoms from one 2,2'-bipyridine (2,2'-bipy) ligand, forming a distorted square-planar geometry. The [Cu(2,2'-bipy)](2+) moieties are bridged by TCB(4-) anions, which lie about inversion centres, forming an infinite one-dimensional coordination polymer with a double-chain structure along the a axis. A two-dimensional network structure is formed via a face-to-face pi-pi interaction between the 2,2'-bipy rings belonging to two adjacent double chains, at a distance of approximately 3.56 A.

catena-Poly[diaquabis(5-chloropyridinium-2-olato-kappaO)copper(II)]-mu-pyrazine-kappa2N:N'] diperchlorate].

In the title compound, [Cu(C(5)H(4)ClNO)(2)(C(4)H(4)N(2))(H(2)O)(2)](ClO(4))(2), the Cu atom, which lies on an inversion centre, has an octahedral environment. The pyrazine ligand also lies about an inversion centre and links adjacent Cu atoms into a chain running along the b axis; perchlorate anions occupy the space between the chains, and the chains use the coordinated water molecules to link to the anions, resulting in a hydrogen-bonded ribbon structure. The donor 5-chloro-2-hydroxypyridine ligand exists in the zwitterionic form, i.e. 5-chloropyridinium-2-olate.