Linear Response Calculations of Lattice Dynamics in Strongly Correlated Systems

We introduce a new linear response method to study the lattice dynamics of materials with strong correlations. It is based on a combination of dynamical mean field theory of strongly correlated electrons and the local density functional theory of electronic structure of solids. We apply the method to study the phonon dispersions of a prototype Mott insulator NiO. Our results show overall much better agreement with experiment than the corresponding local density predictions.Comment: 4 pages, 2 figure

A generalized method for multiple robotic manipulator programming applied to vertical-up welding

The application is described of a weld programming algorithm for vertical-up welding, which is frequently desired for variable polarity plasma arc welding (VPPAW). The Basic algorithm performs three tasks simultaneously: control of the robotic mechanism so that proper torch motion is achieved while minimizing the sum-of-squares of joint displacement; control of the torch while the part is maintained in a desirable orientation; and control of the wire feed mechanism location with respect to the moving welding torch. Also presented is a modification of this algorithm which permits it to be used for vertical-up welding. The details of this modification are discussed and simulation examples are provided for illustration and verification

A Multimodal Analysis of Advertisement of Online Marketplace Shopee

High human mobility demands the world of commerce to be able to provide services and goods quickly according to consumer demand. To overcome this phenomenon, now appears transactions that use the internet media to connect producers and consumers known as online marketplace. This research studies the advertisement in online marketplace named Shopee by using multimodal analysis. Shopee is an online marketplace app for buying and selling on mobile phones with ease and quickly offering a wide range of products. This research deals with linguistic and visual analysis. This research is focused on the function of the advertisement realized in the offer goods for buyers interested to see and buy that found and dominates in the online marketplace named Shopee. Multimodal analysis method that is used in the research is text verbal analysis theory in language metafunction such as ideational, interpersonal, and textual metafunction by Halliday (1994), while visual text using multimodal analysis by Kress and Van Leuwen (1996, 2006) and Cheong (2004). The result of multimodal analysis of advertisement of online marketplace Shopee is described in linguistic and visual analysis.   Keywords: multimodal, metafunctions of language, advertisement, Shope

Electron-phonon relaxation and excited electron distribution in zinc oxide and anatase

We propose a first-principle method for evaluations of the time-dependent electron distribution function of excited electrons in the conduction band of semiconductors. The method takes into account the excitations of electrons by external source and the relaxation to the bottom of conduction band via electron-phonon coupling. The methods permits calculations of the non-equilibrium electron distribution function, the quasi-stationary distribution function with steady-in-time source of light, the time of setting of the quasi-stationary distribution and the time of energy loss via relaxation to the bottom of conduction band. The actual calculations have been performed for titanium dioxide in the anatase structure and zinc oxide in the wurtzite structure. We find that the quasi-stationary electron distribution function for ZnO is a fermi-like curve that rises linearly with increasing excitation energy whereas the analogous curve for anatase consists of a main peak and a shoulder. The calculations demonstrate that the relaxation of excited electrons and the setting of the quasi-stationary distribution occur within the time no more than 500 fsec for ZnO and 100 fsec for anatase. We also discuss the applicability of the effective phonon model with energy-independent electron-phonon transition probability. We find that the model only reproduces the trends in changing of the characteristic times whereas the precision of such calculations is not high. The rate of energy transfer to phonons at the quasi-stationary electron distribution also have been evaluated and the effect of this transfer on the photocatalyses has been discussed. We found that for ZnO this rate is about 5 times less than in anatase.Comment: 21 p., 9 figure

Efek Pemberian Blondo dalam Ransum terhadap Total Koloni Lactobacillus sp, Salmonella sp dan Escherichia coli pada Ileum Broiler

An experiment was conducted to study the effect of feeding by-product from virgin coconut oil processing (blondo) in ration on total colony of Lactobacillus sp, Salmonella sp and Escherichia coli in ileum of broiler. Broilers reared for 6 weeks in Unit Pelaksana Teknis (UPT), at Faculty of Animal Science, University of Andalas. One hundred of broilers strain Cobb on three days old were used. The design of experiment was a Completely Randomized Design (CRD), with 5 treatments (0; 7.5; 15; 22.5 and 30% blondo level in ration) and 4 replications for each treatment. Variables observed were total colony of Lactobacillus sp bacteria, Salmonella sp and Escherichia coli in ileum of broiler at 3 and 6 weeks of age. The result showed, total colony of Lactobacillus sp bacteria highly significant (P<0.01) increased and Salmonella sp highly significant (P<0.01) decreased by treatment at 3 and 6 weeks of age, but only decreased significantly (P<0.05) total colony of Escherichia coli bacteria at 3 weeks of age and highly significant decreased (P<0.01) at 6 weeks of age. The results showed that administration of 15% blondo in ration showed the most optimal results in creating a balance of microflora in ileum of broiler.An experiment was conducted to study the effect of feeding by-product from virgin coconut oil processing (blondo) in ration on total colony of Lactobacillus sp, Salmonella sp and Escherichia coli in ileum of broiler. Broilers reared for 6 weeks in Unit Pelaksana Teknis (UPT), at Faculty of Animal Science, University of Andalas. One hundred of broilers strain Cobb on three days oldwere used. The design of experiment was a Completely Randomized Design (CRD), with 5 treatments (0; 7.5; 15; 22.5 and 30% blondo level in ration) and 4 replications for each treatment. Variables observed were total colony of Lactobacillus sp bacteria, Salmonella sp and Escherichia coli in ileum of broiler at 3 and 6 weeks of age. The result showed, total colony of Lactobacillus sp bacteria highly significant (P<0.01) increased and Salmonella sp highly significant (P<0.01) decreased by treatment at 3 and 6 weeks of age, but only decreased significantly (P<0.05) total colony of Escherichia coli bacteria at 3 weeks of age and highly significant decreased (P<0.01) at 6 weeks of age. The results showedthat administration of15% blondoinrationshowedthemostoptimalresultsincreating abalance ofmicroflorain ileumof broiler.

Inhomogeneous Gutzwiller approximation with random phase fluctuations for the Hubbard model

We present a detailed study of the time-dependent Gutzwiller approximation for the Hubbard model. The formalism, labelled GA+RPA, allows us to compute random-phase approximation-like (RPA) fluctuations on top of the Gutzwiller approximation (GA). No restrictions are imposed on the charge and spin configurations which makes the method suitable for the calculation of linear excitations around symmetry-broken solutions. Well-behaved sum rules are obeyed as in the Hartree-Fock (HF) plus RPA approach. Analytical results for a two-site model and numerical results for charge-charge and current-current dynamical correlation functions in one and two dimensions are compared with exact and HF+RPA results, supporting the much better performance of GA+RPA with respect to conventional HF+RPA theory.Comment: 14 pages, 6 figure

Intestinal microbiota mutualism and gastrointestinal diseases

The purpose of this work is to investigate the link between an altered intestinal mcro-biota or dysbiosis and chronic inflammatory disorders, in particular inflammatory bowel disease (IBD). Along with probiotics, faecal microbiota transplantation (FMT) opts to be a promising therapeutic treatment for restoring the bacterial homeostasis of the hu-man intestine and reducing the risk of colorectal carcinogenesis. Microbiota is the com-plex microbial flora that resides in the gut establishing a mutually beneficial relation-ship. Alteration of the microbiota’s composition, termed as dysbiosis, may lead to pathological conditions. Treatment with probiotics can restore the normal commensal flora in IBD. Intestinal microbiota affects the circadian rhythm which in turn regulates the expression of different genes in GALT (gut associated lymphoid tissue) playing a role in the prevention of inflammation and colorectal cancer (CRC) progression. This article highlights the involvement of different microbial strains in the pathogenesis of dysbiosis and in the creation of a carcinogenic milieu caused by an altered stimulation of the immune system. Therapies targeting the equilibrium of the microbiota to switch off chronic inflammation and prevent the progression to CRC seem to be a promising therapeutic tool for a variety of inflammation-associated diseases

Lattice instabilities of cubic NiTi from first principles

The phonon dispersion relation of NiTi in the simple cubic B2 structure is computed using first-principles density-functional perturbation theory with pseudopotentials and a plane-wave basis set. Lattice instabilities are observed to occur across nearly the entire Brillouin zone, excluding three interpenetrating tubes of stability along the (001) directions and small spheres of stability centered at R. The strongest instability is that of the doubly degenerate M5' mode. The atomic displacements of one of the eigenvectors of this mode generate a good approximation to the observed B19' ground-state structure.Comment: 11 pages, 3 figure

A simple, low-cost conductive composite material for 3D printing of electronic sensors

3D printing technology can produce complex objects directly from computer aided digital designs. The technology has traditionally been used by large companies to produce fit and form concept prototypes (‘rapid prototyping’) before production. In recent years however there has been a move to adopt the technology as full-scale manufacturing solution. The advent of low-cost, desktop 3D printers such as the RepRap and Fab@Home has meant a wider user base are now able to have access to desktop manufacturing platforms enabling them to produce highly customised products for personal use and sale. This uptake in usage has been coupled with a demand for printing technology and materials able to print functional elements such as electronic sensors. Here we present formulation of a simple conductive thermoplastic composite we term ‘carbomorph’ and demonstrate how it can be used in an unmodified low-cost 3D printer to print electronic sensors able to sense mechanical flexing and capacitance changes. We show how this capability can be used to produce custom sensing devices and user interface devices along with printed objects with embedded sensing capability. This advance in low-cost 3D printing with offer a new paradigm in the 3D printing field with printed sensors and electronics embedded inside 3D printed objects in a single build process without requiring complex or expensive materials incorporating additives such as carbon nanotubes

Linear-response theory and lattice dynamics: a muffin-tin orbital approach

A detailed description of a method for calculating static linear-response functions in the problem of lattice dynamics is presented. The method is based on density functional theory and it uses linear muffin-tin orbitals as a basis for representing first-order corrections to the one-electron wave functions. As an application we calculate phonon dispersions in Si and NbC and find good agreement with experiments.Comment: 18 pages, Revtex, 2 ps figures, uuencoded, gzip'ed, tar'ed fil