Composition Dependence of Glass Forming Propensity in Al−Ni Alloys

Enormous progress has been made over the past decade in developing bulk amorphous alloys with high strength and other mechanical properties while possessing improved glass forming and processing abilities. Particularly important in developing new systems is identifying the compositions most likely to lead to glass formation. We illustrate here for the Al−Ni system how Molecular Dynamics (MD) using a force field derived from first-principles quantum mechanics (QM) can be used to determine the optimum compositions for glass forming ability (GFA). Using the Two-Phase Thermodynamics (2PT) method to extract entropy and free energy directly from MD, we find that the GFA is closely related to (ΔG_(lc))_(Tg), the Gibbs free energy difference between the liquid state and crystal state at the glass transition temperature T_g. We find that the glass phase is preferred at compositions where (ΔG_(lc))_(Tg) is small and where the equilibrium crystal structure is complex. For the AlNi alloys, our calculations suggest that the best glass-forming composition is 87.5% Al and 12.5% Ni. On the basis of the Honeycutt−Andersen type of local structure analysis of alloys in the liquid state, we propose an atomic scale explanation of GFA. Large GFA arises when there is a great difference in the atom bonding preference between different atom species

Cohomological rank functions and surfaces of general type with pg=q=2p_g=q=2

We classify minimal surfaces $S$ with $p_g=q=2$ and $K_S^2=5$ or $6$

Molecular dynamics study of the binary Cu_(46)Zr_(54) metallic glass motivated by experiments: Glass formation and atomic-level structure

We have identified a binary bulk metallic glass forming alloy Cu_(46_Zr_(54) by analyzing the structure and thermal behaviors of copper mold cast samples using x-ray diffraction, transmission electron microscopy, and differential scanning calorimeter. Motivated by these experimental results, we fitted the effective Rosato-Guillope-Legrand-type force field parameters for the binary Cu-Zr alloy system and the atomistic description of glass formation and structure analysis of the Cu_(46)Zr_(54) alloy based on molecular dynamics simulation will be also presented

Poboljšana adaptivna pretvorba ostataka prilikom H.264/AVC video kodiranja bez gubitka kvalitete

The H.264/AVC was designed mainly for lossy video coding, the lossless coding of H.264 use bypass mode for DCT and quantization. Although sample-by-sample DPCM improves performance of coding, the benefit is limited in intra. In this paper, a new adaptive transform is proposed based on the character of 4x block residual coefficient\u27s distribution, which can be used both in intra and inter coding. The greatest strength of the proposed transform is the decorrelation without inflation versus dynamic range of input matrix. Due to the random distribution of residual coefficients, a specific transform is hard to play a positive impact on them. Therefore, several transforms of different directions will be implemented simultaneously, and the most efficient one will be determined by a proposed mechanism. Then, by means of statistic method, a new scan order is designed for CAVLC entropy encoder, cooperating with corresponding transform. The simulation results show that based on the fast algorithm of proposed method, the bit saving achieves about 7.41% bit saving in intra coding and 10.47% in inter, compared with H.264-LS.H.264/AVC je napravljen prvenstveno za kodiranje videa uz gubitak kvalitete, dok kodiranje H.264 bez gubitka kvalitete koristi zaobilazni mod za DCT i kvantizaciju. Iako uzorak-po-uzorak (DPCM) kvantizacija poboljšava performanse kodiranja, dobitak je ograničen. U ovom radu predlaže se nova adaptivna transformacija koja se zasniva na znakovima od 4x4 blokova distribucije ostataka koeficijenata, koja može koristiti i unutarnje i među kodiranje. Najveća snaga predložene transformacije je u nekoreliranosti bez inflacije protiv dinamičke veličine ulazne matrice. Radi slučajne distribucije ostataka koeficijenata, teško je postići da određena transformacija ima pozitivan učinak na njih. Iz tog razloga istovremeno je implementirano nekoliko transformacija različitih pristupa, te je korištenjem predloženog mehanizma odabrana najefikasnija. Zatim je, korištenjem statističke metode, dizajniran novi poredak snimanja za CAVLC entropijski enkoder, koji surađuje s odgovarajućom transformacijom. Rezultati simulacija pokazuju da korištenjem brzog algoritma predložene metode dolazi do smanjenja korištenih bitova od 7.41% kod među kodiranja i 10.47% prilikom unutarnjeg kodiranja u usporedbi s H.264-LS

Effect of dexmedetomidine on blood T cell proliferation, T cell subsets and phagocytic function of alveolar macrophages in young rats subjected to splenectomy

Purpose: To study the effect of dexmedetomidine on blood T cell proliferation, T cell subsets and phagocytosis of alveolar macrophages in young rats undergoing splenectomy. Methods: Fifty-four healthy male rats were used for the establishment of an animal model of splenectomy. The young rats were randomly assigned to control, model (untreated) and medication groups, each with 18 rats. The rats in the control and model groups were given physiological saline at a dose of 10 ml/kg, while those in the treatment group were injected with dexmedetomidine at a dose of 50 µg/kg. All treatments were given intraperitoneally (i.p.). T cell proliferation, T cell subset level, phagocytic index and degree of phagocytosis of alveolar macrophages were compared among the rat groups. Results: Relative to control, CD4+, CD8+ and CD4+/CD8+ levels in model and medication groups decreased significantly (p < 0.05). CD4+ and CD8+ levels were lower in the medication group than in model group. Phagocytic index and degree of phagocytosis of alveolar macrophages in model and medication groups were significantly lower than those in the control group, while phagocytic index and degree of phagocytosis of alveolar macrophages in the medication group of rats were smaller than those in model rats (p < 0.05). Conclusion: Dexmedetomidine significantly reduces immune function in splenectomy rats. However, it should be used with caution in patients with splenectomy

Genetic and functional characterization of disease associations explains comorbidity

Understanding relationships between diseases, such as comorbidities, has important socio-economic implications, ranging from clinical study design to health care planning. Most studies characterize disease comorbidity using shared genetic origins, ignoring pathway-based commonalities between diseases. In this study, we define the disease pathways using an interactome-based extension of known disease-genes and introduce several measures of functional overlap. The analysis reveals 206 significant links among 94 diseases, giving rise to a highly clustered disease association network. We observe that around 95% of the links in the disease network, though not identified by genetic overlap, are discovered by functional overlap. This disease network portraits rheumatoid arthritis, asthma, atherosclerosis, pulmonary diseases and Crohn's disease as hubs and thus pointing to common inflammatory processes underlying disease pathophysiology. We identify several described associations such as the inverse comorbidity relationship between Alzheimer's disease and neoplasms. Furthermore, we investigate the disruptions in protein interactions by mapping mutations onto the domains involved in the interaction, suggesting hypotheses on the causal link between diseases. Finally, we provide several proof-of-principle examples in which we model the effect of the mutation and the change of the association strength, which could explain the observed comorbidity between diseases caused by the same genetic alterations