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This paper is concerned with the construction of high order mass-lumping finite elements on simplexes and a program for computing mass-lumping finite elements on triangles and tetrahedra. The polynomial spaces for mass-lumping finite elements, as proposed in the literature, are presented and discussed. In particular, the unisolvence problem of symmetric point-sets for the polynomial spaces used in mass-lumping elements is addressed, and an interesting property of the unisolvent symmetric point-sets is observed and discussed. Though its theoretical proof is still lacking, this property seems to be true in general, and it can greatly reduce the number of cases to consider in the computations of mass-lumping elements. A program for computing mass-lumping finite elements on triangles and tetrahedra, derived from the code for computing numerical quadrature rules presented in [7], is introduced. New mass-lumping finite elements on triangles found using this program with higher orders, namely 7, 8 and 9, than those available in the literature are reported.

Performance of a perovskite based solar cell is highly determined by the crystalline qualities of the perovskite thin film sandwiched between an electron and a hole transport layer, such as grain size and uniformity of the film. Here, we demonstrated a new hybrid physical-chemical vapor deposition (HPCVD) technique to synthesis high quality perovskite films. First, a PbI2 precursor film was spin-coated on a mesoporous TiO2 (m-TiO2)/compact TiO2 (c-TiO2)/FTO substrate in ambient environment. Then, purified CH3NH3I crystal material was evaporated and the vapor reacted with the PbI2 precursor film in a vacuum pressure/temperature accurately controlled quartz tube furnace. In this technique, high vacuum (2mTorr) and low temperature (100°C) were applied to decrease perovskite film growth rate and reduce perovskite film defects. After vapor reaction, the perovskite film was annealed at 100°C for 10min in 20mTorr vacuum to recrystallize and remove CH3NH3I residue in order to further improve crystal quality of the thin film. Crystal quality of this perovskite thin film was characterized by scanning electron microscopy (SEM), atomic force microscopy (AFM), and X-ray diffraction (XRD). SEM and AFM results illustrate perovskite thin films synthesized by this technique have larger grain sizes and more uniformity (RMS 11.6nm/Ra 9.3nm) superior to most existing methods. Strong peaks shown in the XRD chart at 14.18°, 28.52°, 31.96°, which were assigned to (110), (220), (330) miller indices of CH3NH3PbI3 perovskite crystal, indicate the complete reaction between CH3NH3I vapor and PbI2 precursor layer. High power conversion efficiency (PCE) up to 12.3% and stable efficiencies under four hours illumination of AM1.5 standard were achieved by these solar cells. This vacuum/vapor based technique is compatible with conventional semiconductor fabrication techniques and high quality perovskite film could be achieved through delicate process control. Eventually, perovskite based solar cells could be mass produced in low cost for large scale applications by this novel technique.

In this paper, a new discontinuous Galerkin method is developed for the parabolic equation with jump coefficients satisfying the continuous flow condition. Theoretical analysis shows that this method is L2 stable. When the finite element space consists of interpolative polynomials of degrees k, the convergent rate of the semi-discrete discontinuous Galerkin scheme has an order of . Numerical examples for both 1-dimensional and 2-dimensional problems demonstrate the validity of the new method.

Using the INRA – University of Minnesota porcine 7000 Rad Radiation Hybrid panel (IMpRH) containing 118 clones, porcine cellular retinol binding protein gene 1 (RBP1) and plasma retinol binding protein gene 4 (RBP4) were assigned to porcine chromosomes 13 and 14, respectively. The mRNA distributions of the two genes in adult Wuzhishan pig tissues (lung, skeletal muscle, spleen, heart, stomach, large intestine, lymph node, small intestine, liver, brain, kidney and fat) were examined. One single nucleotide polymorphism (SNP) was identified in Laiwu, Wuzhishan, Guizhou, Bama pig breeds and a Tongcheng experimental population and analysed using a polymerase chain reaction–restriction fragment length polymorphism (PCR–RFLP) method. Significant associations were found between different genotypes of A/G156 and maximum carcass length (LM), minimum carcass length (LN), haemoglobin (HGB), mean corpuscular volume haemoglobin (MCH), and day to slaughter weight (age) traits in the Tongcheng experimental population. This SNP locus might be used as a genetic marker in pig breeding and production.

Endo-β-N-acetylglucosaminidase H hydrolyzes the β-(1–4)-glycosidic link of the N,N′-diacetylchitobiose core of high-mannose and hybrid asparagine-linked oligosaccharides. Seven mutants of the active site residues, Asp130 and Glu132, have been prepared, assayed, and crystallized. They include single site mutants of each residue to the corresponding amide, to Ala and to the alternate acidic residue, and to the double amide mutant. The mutants of Asp130 are more active than the corresponding Glu132 mutants, consistent with the assignment of the latter residue as the primary catalytic residue. The amide mutants are more active than the alternate acidic residue mutants, which in turn are more active than the Ala mutants. The structures of the Asn mutant of Asp130 and the double mutant are very similar to that of the wild-type enzyme. Several residues surrounding the mutated residues, including some that form part of the core of the β-barrel and especially Tyr168 and Tyr244, adopt a very different conformation in the structures of the other two mutants of Asp130 and in the Asp mutant of Glu132. The results show that the residues in the upper layers of the β-barrel can organize into two very distinct packing arrangements that depend on subtle electrostatic and steric differences and that greatly affect the geometry of the substrate-binding cleft. Consequently, the relative activities of several of the mutants are defined by structural changes, leading to impaired substrate binding, in addition to changes in functionality.