1,813 research outputs found
The bi-objective travelling salesman problem with profits and its connection to computer networks.
This is an interdisciplinary work in Computer Science and Operational Research. As it is
well known, these two very important research fields are strictly connected. Among other
aspects, one of the main areas where this interplay is strongly evident is Networking. As far
as most recent decades have seen a constant growing of every kind of network computer connections,
the need for advanced algorithms that help in optimizing the network performances
became extremely relevant. Classical Optimization-based approaches have been deeply studied
and applied since long time. However, the technology evolution asks for more flexible and
advanced algorithmic approaches to model increasingly complex network configurations. In
this thesis we study an extension of the well known Traveling Salesman Problem (TSP): the
Traveling Salesman Problem with Profits (TSPP). In this generalization, a profit is associated
with each vertex and it is not necessary to visit all vertices. The goal is to determine
a route through a subset of nodes that simultaneously minimizes the travel cost and maximizes
the collected profit. The TSPP models the problem of sending a piece of information
through a network where, in addition to the sending costs, it is also important to consider
what “profit” this information can get during its routing. Because of its formulation, the
right way to tackled the TSPP is by Multiobjective Optimization algorithms. Within this
context, the aim of this work is to study new ways to solve the problem in both the exact
and the approximated settings, giving all feasible instruments that can help to solve it, and
to provide experimental insights into feasible networking instances
TASSE COME MOTIVATORI E PREDITTORI DELLA RISTRUTTURAZIONE AZIENDALE
There seems to be a common pattern in the way Member States have addressed taxation of company reorganizations. After some uncertainty, operations affecting corporate and shareholding structures were considered as sources of taxable capital gains. As might have been expected, this hindered a more efficient capital allocation, leading to the enforcement of special laws granting limited and conditional exemption aiming to ease the transfer of undertakings, often with extra advantages than what would be necessary. A deeper rethinking
about the very nature of corporate finance transactions at a later stage defined the problem and brought an across-the-board enactment of general provisions for corporate restructuring, inspired by tax-neutrality: roll-over relief and tax deferral, further underpinned by Community law, have since become standards for addressing mergers, divisions, and, to some extent, transfer of assets and exchange of shares. It is arguable whether tax neutrality granted to reorganizations does represent a waiver to the realization principle, or whether instead it is a consistent development of the legal concept of taxable income.
In the former case there would be some grounds to challenge tax neutrality in company restructuring operations that lack commercial reasons through purposive construction or anti-abuse clauses or principles. In the latter, antiavoidance rules should be limited to thwart circumvention of the statutory scope and the spirit of tax law, irrespective of the business purposes of the transactions carried out.Među državama članicama Europske unije (EU) postoji uvelike ujednačeni pristup porezno-pravnim aspektima restrukturiranja trgovačkih društava. Potencijalno nametanje poreza na kapitalne dobitke, ocijenjeno štetnim iz perspektive ekonomske učinkovitosti, uglavnom se uklanja propisivanjem posebnih pravila o jamstvu, tzv.
porezne neutralnosti. Davanje olakšice odgode plaćanja poreza na kapitalni dobitak u tom je smislu standardno rješenje kad je riječ o transakcijama poput spajanja, pripajanja, podjele društava, prijenosa imovine te zamjene dionica. U tom smislu postavlja se pitanje predstavlja li načelo porezne neutralnosti poslovnih restrukturiranja iznimku od načela realizacije ili refleksiju pravnog koncepta oporezivog dohotka/dobiti. U potonjem slučaju, porezna tijela mogu odbiti priznavanje relevantnih olakšica u odnosu na transakcije koje nemaju valjani komercijalni smisao, temeljem tumačenja porezno-pravnih propisa ili izričitih protuevazijskih pravila. Pritom valja naglasiti da
primjena protuevazijskih pravila mora biti ograničena samo na slučajeve kod kojih se izigrava smisao i duh mjerodavnih zakonskih odredbi.Es scheint ein gemeinsames Muster zu geben, mit welchem die EUMitgliedsstaaten die Besteuerung von Unternehmensumstrukturierungen angesprochen haben. Nach einigen Unsicherheiten wurden die Aktivitäten, welche auf die Unternehmens- und Beteiligungsstrukturen einen Einfluss üben, als Quellen der steuerpflichtigen Kapitalerträge angesehen. Wie man hätte erwarten können, hat das die effiziente Kapitalzuweisung gehindert und zur Erlassung spezieller Gesetze zur Gewährleistung begrenzter und bedingter Steuerbefreiung geführt, um Unternehmensübertragungen zu erleichtern, wobei zusätzliche Vorteile öfter als notwendig erteilt wurden. Danach hat man über die Natur der Finanztransaktionen
eines Unternehmens tiefer nachgedacht, was zur Erlassung allgemeiner steuerneutraler Bestimmungen für Unternehmensumstrukturierungen führte: den Abzügen für reinvestierte Gewinne (den sog. „Rollover“) und dem Aufschub der Besteuerung. Diese durch das EU-Recht zusätzlich verstärkten Bestimmungen sind zum Standard bei Fusionen, Teilungen, aber einigermaßen auch bei Übertragungen der Vermögenswerte und Aktientausch geworden. Es lässt sich darüber streiten, ob diese
Steuerneutralität ein Verzicht auf das Realisationsprinzip oder eine Weiterentwicklung des Rechtsinstituts des steuerpflichtigen Einkommens darstellt. Im ersten Fall würden Gründe bestehen, die Steuerneutralität bei Unternehmensumstrukturierungen mit fehlenden wirtschaftlichen Gründen durch zweckorientierte Auslegung oder Anti-
Missbrauchsklausel infrage zu stellen. Im zweiten Fall sollte man die Regeln zur Bekämpfung der Steuervermeidung begrenzen, um die Umgehung des Gesetzes und des Steuerrechts zu verhindern, ungeachtet des Geschäftszwecks der Transaktionen.L’esame comparatistico sembra evidenziare un percorso comune nell’approccio alla tassazione delle riorganizzazioni societarie da parte degli Stati membri dell’UE. Dopo alcune iniziali incertezze, le operazioni aventi impatto sulle strutture societarie e partecipative sono state considerate fonte di plusvalenze e capital gains. Come ci si poteva aspettare ciò finì per ostacolare una efficiente allocazione dei capitali, ponendo le premesse per l’approvazione di speciali leggi agevolative volte a esentare il trasferimento dei complessi aziendali, a volte con concessione di benefici addizionali non necessari. In una fase successiva, un profondo ripensamento della reale natura delle operazioni di ristrutturazione societaria ha portato all’approvazione di norme generali sulle riorganizzazioni societarie, ispirate al principio di neutralità fiscale: il trasferimento in continuità dei valori e la postergazione della tassazione delle plusvalenze, accolti dalla normativa comunitaria, sono diventati il regime standard di fusioni, scissioni e in una certa misura di trasferimenti d’azienda e scambi di partecipazioni. Si può discutere se la neutralità fiscale garantita alle riorganizzazioni
rappresenti una deviazione rispetto al principio del realizzo, o invece uno sviluppo coerente del concetto legale di reddito tassabile. Nel primo caso vi sarebbero argomenti per contestare la neutralità fiscale in operazioni di ristrutturazione privi di ragioni economiche, attraverso interpretazioni finalistiche o regole e principi anti-abuso. Nel secondo caso, le regole anti-elusive dovrebbero invece tendere a disconoscere
i vantaggi ottenuti aggirando lo spirito delle leggi fiscali, a prescindere dagli scopi economici perseguiti
Sealed transformer monitoring
Interest in sealed distribution transformers, with and without gas cushions, increased in the 1950s. However, the tank of hermetically sealed transformers must tolerate a higher pressure, and this can lead to mechanical sealing problems. Contrarily, a lower pressure in the tank can
put the internal dielectric seal at risk. Therefore, the pressure and temperature monitoring in hermetically sealed transformers are crucial to keep the pressure behaviour under control and to have the ability to perform proactive prevention
The effects of microRNAs on human neural stem cell differentiation in two- and three-dimensional cultures
INTRODUCTION: Stem cells have the ability to self-renew or to differentiate into numerous cell types; however, our understanding of how to control and exploit this potential is currently limited. An emerging hypothesis is that microRNAs (miRNAs) play a central role in controlling stem cell-fate determination. Herein, we have characterized the effects of miRNAs in differentiated human neural stem cells (hNSCs) by using a cell line currently being tested in clinical trials for stroke disability (NCT01151124, Clinicaltrials.gov). METHODS: HNSCs were differentiated on 2- (2D) and 3-dimensional (3D) cultures for 1 and 3 weeks. Quantification of hNSC differentiation was measured with real-time PCR and axon outgrowth. The miRNA PCR arrays were implemented to investigate differential expression profiles in differentiated hNSCs. Evaluation of miRNA effects on hNSCs was performed by using transfection of miRNA mimics, real-time PCR, Western blot, and immunocytochemistry. RESULTS: The 3D substrate promoted enhanced hNSC differentiation coupled with a loss of cell proliferation. Differentiated hNSCs exhibited a similar miRNA profiling. However, in 3D samples, the degree and timing of regulation were significantly different in miRNA members of cluster mi-R17 and miR-96-182, and hsa-miR-302a. Overall, hNSC 3D cultures demonstrated differential regulation of miRNAs involved in hNSC stemness, cell proliferation, and differentiation. The miRNA mimic analysis of hsa-miR-146b-5p and hsa-miR-99a confirmed induction of lineage-committed progenitors. Downregulated miRNAs were more abundant; those most significantly downregulated were selected, and their putative target mRNAs analyzed with the aim of unraveling their functionality. In differentiated hNSCs, downregulated hsa-miR-96 correlated with SOX5 upregulation of gene and protein expression; similar results were obtained for hsa-miR-302a, hsa-miR-182, hsa-miR-7, hsa-miR-20a/b, and hsa-miR-17 and their target NR4A3. Moreover, SOX5 was identified as a direct target gene of hsa-miR-96, and NR43A, a direct target of hsa-miR-7 and hsa-mir-17 by luciferase reporter assays. Therefore, the regulatory role of these miRNAs may occur through targeting NR4A3 and SOX5, both reported as modulators of cell-cycle progression and axon length. CONCLUSIONS: The results provide new insight into the identification of specific miRNAs implicated in hNSC differentiation. These strategies may be exploited to optimize in vitro hNSC differentiation potential for use in preclinical studies and future clinical applications
A revolution in progress
We live in an era where technology is advancing at an unprecedented velocity. The offering of online sensors measuring multiple physical parameters has increased immensely. Moving from
traditional maintenance (age-based) to on-time maintenance based on monitoring systems may not be painless. It will be necessary to adopt data collection systems that are reliable and include automatic data processing that helps with data interpretation. This evolution, accompanied by the availability of automatic data processing and Artificial Intelligence (AI), determines a further push of “Industry 4.0” in “Smart Grid.
Fertimetro, a Principle and Device to Measure Soil Nutrient Availability for Plants by Microbial Degradation Rates on Differently-Spiked Buried Threads
A novel patented method (PCT/IB2012/001157: Squartini, Concheri, Tiozzo, University of Padova) and the corresponding application devices, suitable to measure soil fertility, are presented. The availability or deficiency of specific nutrients for crops is assessed by monitoring the kinetics of progressive weakening of cotton or silk threads due to in situ microbial activity. The method is based on a nutrient-primed incremented substrate degradation principle. Threads are buried as is or pre-impregnated with N or P solutions, and the acceleration of the degradation rate for the N-supplemented or P-supplemented thread, in comparison to the untreated thread, is proportional to the lack of the corresponding nutrient in that soil. Tests were validated on corn crops in plots receiving increasing fertilizer rates in a historical rotation that has been established since 1962. The measurement carried out in May significantly correlated with the subsequent crop yields recorded in October. The analysis allows an early, inexpensive, fast, and reproducible self-assessment at field level to improve fertilization rates. The device is envisaged as a user-friendly tool for agronomy, horticulture, and any environmental applications where organic matter cycling, soil quality, and specific nutrients excess or deficiency are critical considerations
Characteristics of Compost Obtained from Winemaking Byproducts
A model procedure for the sustainable management of plant biomass related to wine production, namely vine branches from agricultural practices in the vineyard and marcs remaining after grapes crushing, was devised. An artificial humification process was set up that could respond to the needs of environmental sustainability and could be a safe way to be reintroduce in the vineyard part of the organic matter previously exported, thus contributing to recover or maintain vineyard soil fertility. Two different strategies for composting were tested, namely a static pile, made by branches and marcs, and a pile that was fed twice a year alternatively with vine branches and grape marcs. The experimentation lasted 710 days, during which environmental parameters, i.e. temperature and rainfalls were monitored. Growth dynamics of the principal functional groups of microorganism were followed. A characterization of the composted material was obtained by measuring several parameters among which, pH, carbon, nitrogen, sulfur and heavy metals content. The characteristics of the produced compost fulfill the requirements prescribed by the Italian legislation regarding the use of compost as soil amendment. Germination tests demonstrated the absence of phytotoxicity and conversely evidenced a stimulating activity towards root development
Beneficial Bacteria Isolated from Grapevine Inner Tissues Shape Arabidopsis thaliana Roots
We investigated the potential plant growth-promoting traits of 377 culturable endophytic bacteria, isolated from Vitis vinifera cv. Glera, as good biofertilizer candidates in vineyard management. Endophyte ability in promoting plant growth was assessed in vitro by testing ammonia production, phosphate solubilization, indole-3-acetic acid (IAA) and IAA-like molecule biosynthesis, siderophore and lytic enzyme secretion. Many of the isolates were able to mobilize phosphate (33%), release ammonium (39%), secrete siderophores (38%) and a limited part of them synthetized IAA and IAA-like molecules (5%). Effects of each of the 377 grapevine beneficial bacteria on Arabidopsis thaliana root development were also analyzed to discern plant growth-promoting abilities (PGP) of the different strains, that often exhibit more than one PGP trait. A supervised model-based clustering analysis highlighted six different classes of PGP effects on root architecture. A. thaliana DR5::GUS plantlets, inoculated with IAA-producing endophytes, resulted in altered root growth and enhanced auxin response. Overall, the results indicate that the Glera PGP endospheric culturable microbiome could contribute, by structural root changes, to obtain water and nutrients increasing plant adaptation and survival. From the complete cultivable collection, twelve promising endophytes mainly belonging to the Bacillus but also to Micrococcus and Pantoea genera, were selected for further investigations in the grapevine host plants towards future application in sustainable management of vineyards
Obtención de hidrolizado de aceite de macauba y su aplicación en la producción de ésteres metílicos
This work aimed to obtain a hydrolyzate rich in free fatty acids (FFA) from the hydrolysis of macauba oil for subsequent esterification and obtaining of methyl esters. To determine the conditions that maximize FFA yield in the hydrolysis step, the effects of buffer solution percentage and catalyst concentration (Lipozyme® RM IM) were determined at 55 ºC and 6 h. From the results, it was verified that both variables evaluated in the experimental range had an influence on the reaction and their increase favored the production of FFA. Additional experiments were carried out to assess the influence of reaction time with a progressive increase up to 8 h. Hydrolyzate with ~92 wt % FFA was obtained and its use in the enzymatic esterification step using Novozym® 435 as catalyst resulted in ~95 % FFA conversion. Regarding the reuse of enzymes at each stage, a ~50 % reduction in FFA yield was found and only 98 % FFA conversion.Este trabajo tuvo como objetivo obtener un hidrolizado rico en ácidos grasos libres (AGL) a partir de la hidrólisis del aceite de frutos de macauba, para su posterior esterificación y obtención de ésteres metílicos. Para determinar las condiciones que maximizan el rendimiento de AGL en la etapa de hidrólisis, se determinaron los efectos del porcentaje de solución amortiguadora y la concentración de catalizador (Lipozyme® RM IM) a 55 ºC y 6 h. De los resultados se verificó que ambas variables, en el rango experimental evaluado, tienen influencia en la reacción y su incremento favorece la producción de AGL. Se llevaron a cabo experimentos adicionales para evaluar la influencia del tiempo de reacción, observándose un aumento progresivo hasta las 8 h. Se obtuvo un hidrolizado con ~92 % en peso de FFA y su uso en el paso de esterificación enzimática, usando Novozym® 435 como catalizador, resultó en ~95 % de conversión de FFA. Al investigar la reutilización de enzimas, en cada etapa, se encontró una reducción de ~50 % en el rendimiento de FFA y solo un 98 % en la conversión de FFA
- …