Depth-Resolved Composition and Electronic Structure of Buried Layers and Interfaces in a LaNiO₃/SrTiO₃ Superlattice from Soft- and Hard- X-ray Standing-Wave Angle-Resolved Photoemission

Eiteneer, D.,Palsson, G.K.,Nemsak, S.,Gray, A.X.,Kaiser, A.M.,Son, J.,LeBeau, J.,Conti, G.,Greer, A.A.,Keqi, A.,Rattanachata, A.,Saw, A.Y.,Bostwick, A.,Rotenberg, E.,Gullikson, E.M.,Ueda, S.,Kobayashi Elsevier Scientific Pub. Co 2016 Journal of electron spectroscopy and related pheno Vol.211 No.-

LaNiO<SUB>3</SUB> (LNO) is an intriguing member of the rare-earth nickelates in exhibiting a metal-insulator transition for a critical film thickness of about 4 unit cells [Son et al., Appl. Phys. Lett. 96, 062114 (2010)]; however, such thin films also show a transition to a metallic state in superlattices with SrTiO<SUB>3</SUB> (STO) [Son et al., Appl. Phys. Lett. 97, 202109 (2010)]. In order to better understand this transition, we have studied a strained LNO/STO superlattice with 10 repeats of [4 unit-cell LNO/3 unit-cell STO] grown on an (LaAlO<SUB>3</SUB>)<SUB>0.3</SUB>(Sr<SUB>2</SUB>AlTaO<SUB>6</SUB>)<SUB>0.7</SUB> substrate using soft x-ray standing-wave-excited angle-resolved photoemission (SWARPES), together with soft- and hard- x-ray photoemission measurements of core levels and densities-of-states valence spectra. The experimental results are compared with state-of-the-art density functional theory (DFT) calculations of band structures and densities of states. Using core-level rocking curves and x-ray optical modeling to assess the position of the standing wave, SWARPES measurements are carried out for various incidence angles and used to determine interface-specific changes in momentum-resolved electronic structure. We further show that the momentum-resolved behavior of the Ni 3d e<SUB>g</SUB> and t<SUB>2g</SUB> states near the Fermi level, as well as those at the bottom of the valence bands, is very similar to recently published SWARPES results for a related La<SUB>0.7</SUB>Sr<SUB>0.3</SUB>MnO<SUB>3</SUB>/SrTiO<SUB>3</SUB> superlattice that was studied using the same technique (Gray et al., Europhysics Letters 104, 17004 (2013)), which further validates this experimental approach and our conclusions. Our conclusions are also supported in several ways by comparison to DFT calculations for the parent materials and the superlattice, including layer-resolved density-of-states results.

Network Localization with Assisting Nodes

Carlos A. Gomez-Vega,Zhenyu Liu,Carlos A. Gutierrez,Andrea Conti,Moe Z. Win 한국통신학회 2021 한국통신학회 학술대회논문집 Vol.2021 No.2

Location awareness in wireless networks depends on propagation conditions, transmitting resources, and nodes deployment. A well designed node deployment strategy can enhance the localization performance significantly. In this paper, we present a near-optimal algorithm for deploying assisting nodes in localization networks with limited infrastructure. First, we formulate the node deployment task as an optimization problem to minimize the localization error of an agent. Then, we develop a node deployment algorithm based on this formulation. Finally, we present a case study to validate the proposed algorithm.

Distributed Network Secrecy

Lee, J.,Conti, A.,Rabbachin, A.,Win, M. Z. IEEE 2013 IEEE journal on selected areas in communications Vol.31 No.9

<P>Secrecy is essential for a variety of emerging wireless applications where distributed confidential information is communicated in a multilevel network from sources to destinations. Network secrecy can be accomplished by exploiting the intrinsic properties of multilevel wireless networks (MWN). This paper introduces the concept of distributed network secrecy (DNS) and develops a framework for the design and analysis of secure, reliable, and efficient MWNs. Our framework accounts for node spatial distribution, multilevel cluster formation, propagation medium, communication protocol, and energy consumption. This research provides a foundation for DNS and offers a new perspective on the relationship between DNS and network lifetime.</P>

Network Experimentation for Cooperative Localization

Conti, A.,Guerra, M.,Dardari, D.,Decarli, N.,Win, M. Z. IEEE 2012 IEEE journal on selected areas in communications Vol.30 No.2

<P>This paper introduces the notion of network experimentation and proposes an experimentation methodology particularly suited for cooperative wireless networks. Based on this methodology we performed extensive measurement campaigns and compare various cooperative localization techniques under a common setting. Network experiments enable (i) the quantification of cooperation benefits, (ii) the development of techniques for harnessing environmental information, and (iii) the characterization of network localization algorithms. As a case study, we consider ultrawide bandwidth cooperative location-aware networks in cluttered indoor environments and evaluate their performance based on measurements collected from network experiments.</P>

Pseudo-Riemannian Sasaki solvmanifolds

Diego Conti,Federico A. Rossi,Romeo Segnan Dalmasso 대한수학회 2023 대한수학회지 Vol.60 No.1

We study a class of left-invariant pseudo-Riemannian Sasaki metrics on solvable Lie groups, which can be characterized by the property that the zero level set of the moment map relative to the action of some one-parameter subgroup $\{\exp tX\}$ is a normal nilpotent subgroup commuting with $\{\exp tX\}$, and $X$ is not lightlike. We characterize this geometry in terms of the Sasaki reduction and its pseudo-K\"ahler quotient under the action generated by the Reeb vector field. We classify pseudo-Riemannian Sasaki solvmanifolds of this type in dimension $5$ and those of dimension $7$ whose K\"ahler reduction in the above sense is abelian.

Mare's Colostrum Globules Stimulate Fibroblast Growth In Vitro: A Biochemical Study

S. Zava,C. Barello,A. Pessione,L. Perono Garoffo,P. Fattori,G. Montorfano,A. Conti,C. Giunta,E. Pessione,B. Berra,M.G. Giuffrida 한국식품영양과학회 2009 Journal of medicinal food Vol.12 No.4

The wound repair function of mare's milk and colostrum was investigated. Mare's colostrum improved wound healing in vivo; thus fibroblast growth activation by mare's milk and colostrum was examined. As expected, colostrum was more effective than milk. To establish the biochemical nature of the bioactive molecules involved, colostrum was fractionated into whey, casein, and fat globules, and the efficacy of these fractions on fibroblast proliferation was studied. The fat globule fraction provided the strongest stimulation; its composition was studied and compared with the less-active milk fat globule fraction. The lipid pattern highlighted several differences between mare's colostrum and milk; in particular, total lipid, linoleic acid, linolenic acid, ganglioside, and glycolipid contents were higher in colostrum. A proteomic investigation revealed some differences between the protein composition of colostrum and milk fat globules. Adipophylin and lactadherin were significantly overexpressed in colostrum fat globules. The role of specific lipids on skin wound repair and that of the epidermal growth factor-like domain, embedded within the lactadherin molecule and probably released in conditions stimulating proteolysis, are discussed.

Mare's Colostrum Globules Stimulate Fibroblast Growth In Vitro: A Biochemical Study

Zava, S.,Barello, C.,Pessione, A.,Garoffo, L. Perono,Fattori, P.,Montorfano, G.,Conti, A.,Giunta, C.,Pessione, E.,Berra, B.,Giuffrida, M.G. The Korean Society of Food Science and Nutrition 2009 Journal of medicinal food Vol.12 No.4

The wound repair function of mare's milk and colostrum was investigated. Mare's colostrum improved wound healing in vivo; thus fibroblast growth activation by mare’s milk and colostrum was examined. As expected, colostrum was more effective than milk. To establish the biochemical nature of the bioactive molecules involved, colostrum was fractionated into whey, casein, and fat globules, and the efficacy of these fractions on fibroblast proliferation was studied. The fat globule fraction provided the strongest stimulation; its composition was studied and compared with the less-active milk fat globule fraction. The lipid pattern highlighted several differences between mare’s colostrum and milk; in particular, total lipid, linoleic acid, linolenic acid, ganglioside, and glycolipid contents were higher in colostrum. A proteomic investigation revealed some differences between the protein composition of colostrum and milk fat globules. Adipophylin and lactadherin were significantly over-expressed in colostrum fat globules. The role of specific lipids on skin wound repair and that of the epidermal growth factor-like domain, embedded within the lactadherin molecule and probably released in conditions stimulating proteolysis, are discussed.

Micro-Grids Reliability Enhancement Under Different Penetration Levels of Hybrid DG Units

M. Essam,Y. M. Atwa,E. F. El-Saadany,S. Conti,S. A. Rizzo 대한전기학회 2018 Journal of Electrical Engineering & Technology Vol.13 No.4

Novel mechanism of customized adequacy formulation is proposed in order to enhance micro grids system reliability. The mechanism accounts for 2-levles of load curtailment, and is mainly based on probabilistic load profile and hybrid Distributed Generation (DG) units modeling. The two load curtailments are needed in order to ensure adequate technical constraints at steady state condition during islanding mode of operation. The effectiveness of the proposed formulation has been verified using system independent analytical expressions for the evaluation of both reliability and Expected Energy Not Served (EENS) indices. The evaluation has examined the impact of different penetration levels of Hybrid DG Units in case study islands. Results show the enhancement of the overall distribution system reliability and the recommended conditions for successful islanding mode of operation.