180 research outputs found
Perancangan Dan Implementasi Augmented Reality Sebagai Media Promosi Penjualan Perumahan
Untuk melakukan promosi sebuah Perumahan banyak cara yang dapat dilakukan, misalnya dengan menggunakan brosur yang mana informasinya disampaikan dalam media dua dimensi, maket yang mana informasinya sudah dapat disampaikan dalam media tiga dimensi tetapi harus memerlukan ruang yang tidak sedikit untuk mewujudkannya demi mendapatkan hasil yang maksimal. Yang menjadi masalah disini adalah bagaimana menjadikan suatu informasi tersebut menjadi interaktif dan lebih menarik bagi konsumen. Dengan menggunakan teknik promosi berbasis augmented reality yang dibuat dengan menggunakan ARTool Kit sebagai komponen yang utama dan dengan menggunakan 3DS Max sebagai software untuk menghasilkan gambar yang menarik. Proses perancangan dan pembuatan teknik promosiini akan menggunkan metode waterfall. Kelebihan dari model waterfall adalah struktur tahap pengembangan sistem jelas, dokumentasi dihasilkan disetiap tahap pengembangan, dan sebuah tahap dijalankan setelah tahap sebelumnya selesai dijalankan (tidak ada tumpang tindih pelaksanaan tahap). Hasil dari perancangan aplikasi ini adalah terealisasinya suatu aplikasi untuk kepentingan promosipenjualan Perumahan yang lebih menarik dan interaktif dengan konsumen berbasis augmented reality. Dengan adanya aplikasi ini diharapkan metode promosi dapat berkembang dengan lebih menarik dan tentunya dengan mengandalkan teknologitanpa membutuhkan ruang yang banyak untuk mencapai hasil yang maksimal
Au-Ag template stripped pattern for scanning probe investigations of DNA arrays produced by Dip Pen Nanolithography
We report on DNA arrays produced by Dip Pen Nanolithography (DPN) on a novel
Au-Ag micro patterned template stripped surface. DNA arrays have been
investigated by atomic force microscopy (AFM) and scanning tunnelling
microscopy (STM) showing that the patterned template stripped substrate enables
easy retrieval of the DPN-functionalized zone with a standard optical
microscope permitting a multi-instrument and multi-technique local detection
and analysis. Moreover the smooth surface of the Au squares (abput 5-10
angstrom roughness) allows to be sensitive to the hybridization of the
oligonucleotide array with label-free target DNA. Our Au-Ag substrates,
combining the retrieving capabilities of the patterned surface with the
smoothness of the template stripped technique, are candidates for the
investigation of DPN nanostructures and for the development of label free
detection methods for DNA nanoarrays based on the use of scanning probes.Comment: Langmuir (accepted
Extensive and Intimate Association of the Cytoskeleton with Forming Silica in Diatoms: Control over Patterning on the Meso- and Micro-Scale
BACKGROUND: The diatom cell wall, called the frustule, is predominantly made out of silica, in many cases with highly ordered nano- and micro-scale features. Frustules are built intracellularly inside a special compartment, the silica deposition vesicle, or SDV. Molecules such as proteins (silaffins and silacidins) and long chain polyamines have been isolated from the silica and shown to be involved in the control of the silica polymerization. However, we are still unable to explain or reproduce in vitro the complexity of structures formed by diatoms. METHODS/PRINCIPAL FINDING: In this study, using fluorescence microscopy, scanning electron microscopy, and atomic force microscopy, we were able to compare and correlate microtubules and microfilaments with silica structure formed in diversely structured diatom species. The high degree of correlation between silica structure and actin indicates that actin is a major element in the control of the silica morphogenesis at the meso and microscale. Microtubules appear to be involved in the spatial positioning on the mesoscale and strengthening of the SDV. CONCLUSIONS/SIGNIFICANCE: These results reveal the importance of top down control over positioning of and within the SDV during diatom wall formation and open a new perspective for the study of the mechanism of frustule patterning as well as for the understanding of the control of membrane dynamics by the cytoskeleton
A parton picture of de Sitter space during slow-roll inflation
It is well-known that expectation values in de Sitter space are afflicted by
infra-red divergences. Long ago, Starobinsky proposed that infra-red effects in
de Sitter space could be accommodated by evolving the long-wavelength part of
the field according to the classical field equations plus a stochastic source
term. I argue that--when quantum-mechanical loop corrections are taken into
account--the separate-universe picture of superhorizon evolution in de Sitter
space is equivalent, in a certain leading-logarithm approximation, to
Starobinsky's stochastic approach. In particular, the time evolution of a box
of de Sitter space can be understood in exact analogy with the DGLAP evolution
of partons within a hadron, which describes a slow logarithmic evolution in the
distribution of the hadron's constituent partons with the energy scale at which
they are probed.Comment: 36 pages; uses iopart.cls and feynmp.sty. v2: Minor typos corrected.
Matches version published in JCA
IR Divergences in Inflation and Entropy Perturbations
We study leading order perturbative corrections to the two point correlation
function of the scalar field describing the curvature perturbation in a
slow-roll inflationary background, paying particular attention to the
contribution of entropy mode loops. We find that the infrared divergences are
worse than in pure de Sitter space: they are power law rather than logarithmic.
The validity of perturbation theory and thus of the effective field theory of
cosmological perturbations leads to stringent constraints on the coupling
constants describing the interactions, in our model the quartic
self-interaction coupling constant of the entropy field. If the self coupling
constant is larger than some critical value which depends in particular on the
duration of the inflationary phase, then perturbation theory breaks down. Our
analysis may have implications for the stability of de Sitter space: the
quantum effects which lead to an instability of de Sitter space will be larger
in magnitude in the presence of entropy fluctuations.Comment: 28 pages, minor changes in Sec 3.3, reference adde
AFM, SEM and TEM Studies on Porous Anodic Alumina
Porous anodic alumina (PAA) has been intensively studied in past decade due to its applications for fabricating nanostructured materials. Since PAA’s pore diameter, thickness and shape vary too much, a systematical study on the methods of morphology characterization is meaningful and essential for its proper development and utilization. In this paper, we present detailed AFM, SEM and TEM studies on PAA and its evolvements with abundant microstructures, and discuss the advantages and disadvantages of each method. The sample preparation, testing skills and morphology analysis are discussed, especially on the differentiation during characterizing complex cross-sections and ultrasmall nanopores. The versatility of PAAs is also demonstrated by the diversity of PAAs’ microstructure
Cationic Amino Acids Specific Biomimetic Silicification in Ionic Liquid: A Quest to Understand the Formation of 3-D Structures in Diatoms
The intricate, hierarchical, highly reproducible, and exquisite biosilica structures formed by diatoms have generated great interest to understand biosilicification processes in nature. This curiosity is driven by the quest of researchers to understand nature's complexity, which might enable reproducing these elegant natural diatomaceous structures in our laboratories via biomimetics, which is currently beyond the capabilities of material scientists. To this end, significant understanding of the biomolecules involved in biosilicification has been gained, wherein cationic peptides and proteins are found to play a key role in the formation of these exquisite structures. Although biochemical factors responsible for silica formation in diatoms have been studied for decades, the challenge to mimic biosilica structures similar to those synthesized by diatoms in their natural habitats has not hitherto been successful. This has led to an increasingly interesting debate that physico-chemical environment surrounding diatoms might play an additional critical role towards the control of diatom morphologies. The current study demonstrates this proof of concept by using cationic amino acids as catalyst/template/scaffold towards attaining diatom-like silica morphologies under biomimetic conditions in ionic liquids
Dark Energy and Gravity
I review the problem of dark energy focusing on the cosmological constant as
the candidate and discuss its implications for the nature of gravity. Part 1
briefly overviews the currently popular `concordance cosmology' and summarises
the evidence for dark energy. It also provides the observational and
theoretical arguments in favour of the cosmological constant as the candidate
and emphasises why no other approach really solves the conceptual problems
usually attributed to the cosmological constant. Part 2 describes some of the
approaches to understand the nature of the cosmological constant and attempts
to extract the key ingredients which must be present in any viable solution. I
argue that (i)the cosmological constant problem cannot be satisfactorily solved
until gravitational action is made invariant under the shift of the matter
lagrangian by a constant and (ii) this cannot happen if the metric is the
dynamical variable. Hence the cosmological constant problem essentially has to
do with our (mis)understanding of the nature of gravity. Part 3 discusses an
alternative perspective on gravity in which the action is explicitly invariant
under the above transformation. Extremizing this action leads to an equation
determining the background geometry which gives Einstein's theory at the lowest
order with Lanczos-Lovelock type corrections. (Condensed abstract).Comment: Invited Review for a special Gen.Rel.Grav. issue on Dark Energy,
edited by G.F.R.Ellis, R.Maartens and H.Nicolai; revtex; 22 pages; 2 figure
Intratumoral heterogeneity and clonal evolution in liver cancer
Clonal evolution of a tumor ecosystem depends on different selection pressures that are principally immune and treatment mediated. We integrate RNA-seq, DNA sequencing, TCR-seq and SNP array data across multiple regions of liver cancer specimens to map spatio-temporal interactions between cancer and immune cells. We investigate how these interactions reflect intra-tumor heterogeneity (ITH) by correlating regional neo-epitope and viral antigen burden with the regional adaptive immune response. Regional expression of passenger mutations dominantly recruits adaptive responses as opposed to hepatitis B virus and cancer-testis antigens. We detect different clonal expansion of the adaptive immune system in distant regions of the same tumor. An ITH-based gene signature improves single-biopsy patient survival predictions and an expression survey of 38,553 single cells across 7 regions of 2 patients further reveals heterogeneity in liver cancer. These data quantify transcriptomic ITH and how the different components of the HCC ecosystem interact during cancer evolution
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