Ab-initio transport properties of nanostructures from maximally-localized Wannier functions

We present a comprehensive first-principles study of the ballistic transport properties of low dimensional nanostructures such as linear chains of atoms (Al, C) and carbon nanotubes in presence of defects. A novel approach is introduced where quantum conductance is computed from the combination of accurate plane-wave electronic structure calculations, the evaluation of the corresponding maximally-localized Wannier functions, and the calculation of transport properties by a real-space Green's function method based on the Landauer formalism. This approach is computationally very efficient, can be straightforwardly implemented as a post-processing step in a standard electronic-structure calculation, and allows to directly link the electronic transport properties of a device to the nature of the chemical bonds, providing insight onto the mechanisms that govern electron flow at the nanoscale.Comment: to be published in Phys. Rev. B (2003

Ballistic Transport in Carbon Nanotubes from First-Principles Molecular Dynamics Simulations

We determined the Landauer ballistic conductance of pristine nanotubes at finite temperature via a novel scheme that combines ab-initio molecular dynamics, maximally-localized Wannier functions, and a tight-binding formulation of electronic transport in nanostructures. Large-scale ab-initio molecular dynamics simulations are used to obtain efficiently accurate trajectories in phase space. The extended Bloch orbitals for states along these trajectories are converted into maximally-localized orbitals, providing an exact mapping of the ground-state electronic structure onto a short-ranged Hamiltonian. Green's functions, self-energies, and ballistic conductance can then be obtained for any given configuration, and averaged over the appropriate statistical ensemble.Singapore-MIT Alliance (SMA

A New ELISA Using the ANANAS Technology Showing High Sensitivity to diagnose the Bovine Rhinotracheitis from Individual Sera to Pooled Milk

Diagnostic tests for veterinary surveillance programs should be efficient, easy to use and, possibly, economical. In this context, classic Enzyme linked ImmunoSorbent Assay (ELISA) remains the most common analytical platform employed for serological analyses. The analysis of pooled samples instead of individual ones is a common procedure that permits to certify, with one single test, entire herds as "disease-free". However, diagnostic tests for pooled samples need to be particularly sensitive, especially when the levels of disease markers are low, as in the case of anti-BoHV1 antibodies in milk as markers of Infectious Bovine Rhinotracheitis (IBR) disease. The avidin-nucleic-acid-nanoassembly (ANANAS) is a novel kind of signal amplification platform for immunodiagnostics based on colloidal poly-avidin nanoparticles that, using model analytes, was shown to strongly increase ELISA test performance as compared to monomeric avidin. Here, for the first time, we applied the ANANAS reagent integration in a real diagnostic context. The monoclonal 1G10 anti-bovine IgG1 antibody was biotinylated and integrated with the ANANAS reagents for indirect IBR diagnosis from pooled milk mimicking tank samples from herds with IBR prevalence between 1 to 8%. The sensitivity and specificity of the ANANAS integrated method was compared to that of a classic test based on the same 1G10 antibody directly linked to horseradish peroxidase, and a commercial IDEXX kit recently introduced in the market. ANANAS integration increased by 5-fold the sensitivity of the 1G10 mAb-based conventional ELISA without loosing specificity. When compared to the commercial kit, the 1G10-ANANAS integrated method was capable to detect the presence of anti-BHV1 antibodies from bulk milk of gE antibody positive animals with 2-fold higher sensitivity and similar specificity. The results demonstrate the potentials of this new amplification technology, which permits improving current classic ELISA sensitivity limits without the need for new hardware investments

Band Structure and Quantum Conductance of Nanostructures from Maximally-Localized Wannier Functions: The Case of Functionalized Carbon Nanotubes

We have combined large-scale, $\Gamma$-point electronic-structure calculations with the maximally-localized Wannier functions approach to calculate efficiently the band structure and the quantum conductance of complex systems containing thousands of atoms while maintaining full first-principles accuracy. We have applied this approach to study covalent functionalizations in metallic single-walled carbon nanotubes. We find that the band structure around the Fermi energy is much less dependent on the chemical nature of the ligands than on the $sp^3$ functionalization pattern disrupting the conjugation network. Common aryl functionalizations are more stable when paired with saturating hydrogens; even when paired, they still act as strong scattering centers that degrade the ballistic conductance of the nanotubes already at low degrees of coverage.Comment: To be published in Phys. Rev. Let

The effects of chronic lifelong activation of the AHR pathway by industrial chemical pollutants on female human reproduction

Environmental chemicals, such as heavy metals, affect female reproductive function. A biological sensor of the signals of many toxic chemical compounds seems to be the aryl hydrocarbon receptor (AHR). Previous studies demonstrated the environmental of heavy metals in Taranto city (Italy), an area that has been influenced by anthropogenic factors such as industrial activities and waste treatments since 1986. However, the impact of these elements on female fertility in this geographic area has never been analyzed. Thus, in the present study, we evaluated the AHR pathway, sex steroid receptor pattern and apoptotic process in granulosa cells (GCs) retrieved from 30 women, born and living in Taranto, and 30 women who are living in non-contaminated areas (control group), who were undergoing in vitro fertilization (IVF) protocol. In follicular fluids (FFs) of both groups the toxic and essential heavy metals, such as chromiun (Cr), Manganese (Mn), iron (Fe), cobalt (Co), nickel (Ni), copper (Cu), zinc (Zn), cadmium (Cd) and lead (Pb), were also analyzed. Higher levels of Cr, Fe, Zn and Pb were found in the FFs of the women from Taranto as compared to the control group, as were the levels of AHR and AHR-dependent cytochrome P450 1A1 and 1B1; while CYP19A1 expression was decreased. The anti-apoptotic process found in the GCs of women fromTaranto was associated with the highest levels of progesterone receptor membrane component 1(PGRMC1), a novel progesterone receptor, the expression of which is subjected to AHR activated by its highest affinity ligands (e.g., dioxins) or indirectly by other environmental pollutants, such as heavy metals. In conclusion, decreased production of estradiol and decreased number of retrieved mature oocytes found in women from Taranto could be due to chronic exposure to heavy metals, in particular to Cr and Pb

Low-Complexity Dynamic Directional Modulation: Vulnerability and Information Leakage

In this paper, the privacy of wireless transmissions is improved through the use of an efficient technique termed dynamic directional modulation (DDM), and is subsequently assessed in terms of the measure of information leakage. Recently, a variation of DDM termed low-power dynamic directional modulation (LPDDM) has attracted significant attention as a prominent secure transmission method due to its ability to further improve the privacy of wireless communications. Roughly speaking, this modulation operates by randomly selecting the transmitting antenna from an antenna array whose radiation pattern is well known. Thereafter, the modulator adjusts the constellation phase so as to ensure that only the legitimate receiver recovers the information. To begin with, we highlight some privacy boundaries inherent to the underlying system. In addition, we propose features that the antenna array must meet in order to increase the privacy of a wireless communication system. Last, we adopt a uniform circular monopole antenna array with equiprobable transmitting antennas in order to assess the impact of DDM on the information leakage. It is shown that the bit error rate, while being a useful metric in the evaluation of wireless communication systems, does not provide the full information about the vulnerability of the underlying system

Типологія синтаксичних конструкцій в німецькій та українській мовах

Німецька та українська мови є односистемними мовами: обидві належать до індоєвропейської мовної сім’ї. Спільні корені та тривалий період ізольованого розвитку, вказують на те, що вказані мови мають характеристики подібності та відмінності в своій внутрішній будові. Німецька та українська належать до синтетичного типу флективних мов. Це означає, що граматичне значення слів у них виражається, здебільшого, за допомогою системи флексій і реалізується в межах одного графічного слова. Але флективна система німецької мови бідніша, ніж у слов’янських мовах.Немецкий и украинский языки являются односистемными языками: оба принадлежат к индоевропейской языковой семье. Общие корни и длительный период изолированного развития, указывают на то, что указанные языки имеют характеристики сходства и различия в своем внутреннем строении. Немецкий и украинский принадлежат к синтетическому типу флективных языков. Это означает, что грамматическое значение слов в них выражается, в основном, с помощью системы флексий и реализуется в пределах одного графического слова. Но флективная система немецкого языка беднее, чем в славянских языках.German and Ukrainian are single-system languages: both belong to the Indo-European language family. Common roots and a long period of isolated development, indicate that these languages ​​have characteristics of similarity and differences in their internal structure. German and Ukrainian belong to the synthetic type of inflectional languages. This means that the grammatical meaning of words in them is expressed, mainly, with the help of a system of inflexions and is realized within a single graphic word. But the inflectional system of the German language is poorer than in the Slavic languages

Semantic-Functional Communications in Cyber-Physical Systems

This paper explores the use of semantic knowledge inherent in the cyber-physical system (CPS) under study in order to minimize the use of explicit communication, which refers to the use of physical radio resources to transmit potentially informative data. It is assumed that the acquired data have a function in the system, usually related to its state estimation, which may trigger control actions. We propose that a semantic-functional approach can leverage the semantic-enabled implicit communication while guaranteeing that the system maintains functionality under the required performance. We illustrate the potential of this proposal through simulations of a swarm of drones jointly performing remote sensing in a given area. Our numerical results demonstrate that the proposed method offers the best design option regarding the ability to accomplish a previously established task -- remote sensing in the addressed case -- while minimising the use of radio resources by controlling the trade-offs that jointly determine the CPS performance and its effectiveness in the use of resources. In this sense, we establish a fundamental relationship between energy, communication, and functionality considering a given end application

Diagnosi e valutazione della personalit alleanza terapeutica e scambio clinico nella ricerca in psicoterapia

Questo contributo si propone di fornire una breve rassegna delle principali linee di ricerca seguite negli ultimi anni dal gruppo coordinato da Vittorio Lingiardi. Tra queste, ci soffermeremo in particolare su: a) valutazione e diagnosi della personalità con SWAP-200 e PDM (Psychodynamic Diagnostic Manual); b) sviluppo e validazione di strumenti clinician-report per operazionalizare l'uso del PDM; c) valutazione dei meccanismi di difesa e degli stili difensivi mediante DMRS e sua versione Q sort; d) studio del processo e della relazione terapeutica (alleanza terapeutica, rotture e riparazioni dell'alleanza controtransfert); in particolare, in quest'area di ricerca, ci siamo impegnati nello sviluppo e validazione di nuovi strumenti per la valutazione dei processi di rottura e riparazione dell'alleanza (Collaborative Interaction Scale) e della qualità dell'attaccamento tra paziente e terapeuta (Patient-Therapist Attachment Q Sort); d) sviluppo della ricerca clinica e applicativa sui temi dell'identità di genere, dell'orientamento sessuale e dell'omofobia sociale e interiorizzata

Diagnosi e valutazione della personalit alleanza terapeutica e scambio clinico nella ricerca in psicoterapia

Questo contributo si propone di fornire una breve rassegna delle principali linee di ricerca seguite negli ultimi anni dal gruppo coordinato da Vittorio Lingiardi. Tra queste, ci soffermeremo in particolare su: a) valutazione e diagnosi della personalità con SWAP-200 e PDM (Psychodynamic Diagnostic Manual); b) sviluppo e validazione di strumenti clinician-report per operazionalizare l'uso del PDM; c) valutazione dei meccanismi di difesa e degli stili difensivi mediante DMRS e sua versione Q sort; d) studio del processo e della relazione terapeutica (alleanza terapeutica, rotture e riparazioni dell'alleanza controtransfert); in particolare, in quest'area di ricerca, ci siamo impegnati nello sviluppo e validazione di nuovi strumenti per la valutazione dei processi di rottura e riparazione dell'alleanza (Collaborative Interaction Scale) e della qualità dell'attaccamento tra paziente e terapeuta (Patient-Therapist Attachment Q Sort); d) sviluppo della ricerca clinica e applicativa sui temi dell'identità di genere, dell'orientamento sessuale e dell'omofobia sociale e interiorizzata