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Lattice dynamics of carbon nanotube interacting with hydroxyapatite

One of the characteristics to be achieved by biomaterials is to have similarity to the host material. In cases of bone substitution, hydroxyapatite (HA) shows considerable similarities to human bone. However, it shows itself with low mechanical resistance, which in many cases makes it difficult to apply in areas subject to high mechanical stress. Carbon nanotubes (CNTs) have low density and strong covalent bonding between their atoms, which gives high mechanical resistance to the material. For this reason, the influence with the HA structure of single wall, pristine CNTs and functionalized with organic hydroxyl (-OH) and carboxyl (-COOH) clusters with functionalization concentrations of 5, 10, 15, 20 and 25% were studied by means of computational simulation. The software used to perform the calculations was GULP and the applied force field was DREIDING. The lattice dynamics revealed that pristine CNTs have a lower interaction with HA because of their high chemical stability. In contrast, the CNTs functionalized with -OH and -COOH interacted better with the HA matrix, indicating that the functionalization may be a factor that optimizes the interaction between these materials. The results of the Root Mean Square Deviation (RMSD), for all systems with functionalized CNTs, reach a stability around a point of equilibrium around 15ps, proving that the interactions are stable. The calculation of the Bulk modulus indicated that we can control the ability of this material to resist volume changes for a given applied pressure, modifying the amount of functionalization present in the CNTs. The functionalities of 20% of -OH and -COOH present greater difficulty in undergoing deformations (greater value of the Bulk module). On the other hand, the functionalizations of 15% of -OH and 5% of -COOH were the most vulnerable to deformation (lower value of the Bulk module). Finally, the Poisson ratio indicates that the theoretical model applied to the systems is reasonable since these coefficients were within the proposed theoretical range.

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Enhancement of quantum efficiency of hybrid photoelectrochemical cell: Effect of functionalized carbon nanotube with Cu doped ZnO nanocomplex

The great energy challenge facing by mankind is due to the depletion of fossil fuels at an alarming rate with exponential increase in population and growing demand in their modern lifestyle. To overcome this situation, utiliszation of omnipresent and abundant solar energy has become the most promising one. Current research work is concentrated on developing new and novel systems to harvest solar energy with greater efficiency. The emergence of nanomaterials has opened up many innovative ways and new initiatives are taken for fabrication of hybrid solar cell. ZnO nanoparticles are considered to be one of the most important material owing to  several unique features and wide range of technologically important applications such as solar cell. The optical and electrical properties of ZnO are significantly improved by Cu doping. For further development of optical properties, researches on hybrid materials of ZnO and carbon nanotubes (CNTs) have received extensive attention.

We have studied the effect of addition of Cu doped ZnO nanoparicle (CZNP) and functionalized carbon nanotubes complex (CZNP/FMWCNT) with PSF dye for photovoltage generation in hybrid PEC cell. The CZNP-FMWCNT complexes were synthesized via wet chemical method. XRD, FESEM, EDAX and Raman spectroscopy confirmed the formation of well crystalline complex system with a certain concentration of FMWCNT. Then PSF dye was added to this complex and used in a hybrid photoelectrochemical (PEC) cell for photovoltage generation. The maximum voltage generation was of the order of 712.6 mV and storage duration was ~55 hrs. The energy conversion efficiency (η%) was 3.34%. UV-Vis spectra of the system with unchanged peak position of dye ascertained adsorption of dye molecules on the surface of CZNP/FMWCNT.

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Use of novel metallic nanoparticles for improvement of electrical properties of PVDF-HFP polymer film

Nanomaterials of copper and cobalt were formed in alcohol in a novel way.  Incorporation of   these materials by simple solution casting technique in poly vinylidene fluoride-co-hexafluoropropylene (PVDF-HFP) polymer films significantly improves their electrical properties.

These films have higher dielectric permittivity and lower dissipation factor (tanδ) at room temperature, compared to the pure PVDF-HFP. The incorporation can be used to increase the dielectric constant of the pure film at 20 Hz frequency upto a maximum of four times.

Presence of α- and β-phases and spherulitic crystal structure of PVDF-HFP of these nanocomposite films have been detected by XRD, FTIR, DTA and FESEM studies.  The incorporation of the nanomaterial  in the polymer matrix  activates the transition of phase between α and β. This provides higher mobility of the charge carriers which participate in the interfacial polarization.

 These nanoparticles are easy to fabricate and environment friendly and their presence  in polymer matrix  to get enhanced  electrical properties will have a significant contribution in the present day research in electronics.        

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Contentious jurisdiction and voluntary jurisdiction

Jurisdiction is a word that derives from the Latin expression jus- dires that means to say the right, it is the power of the State to desire and apply the right to particular cases, exercised through the judges, who have been invested to administer justice. The jurisdiction in its actions is indivisible, it is the interest of the State and its obligation, for the peaceful coexistence of its inhabitants, to apply the law for the maintenance of the legal order created by it. Jurisdiction is a function in which state activity is manifested in the sphere of social relations, which are established in connection with the administration of justice, by bodies created for that purpose. Within this jurisdictional function of the State is the so-called civil jurisdiction, which is that part of the jurisdiction that has as its function the knowledge, investigation and decision of the claims on personal and patrimonial rights, acted by the courts in accordance with the provisions of the substantive and procedural law in a timely manner.

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The imputability from the perspective of comparative law

The topic of imputability has had a different approach in the different Codes of the world in accordance with the development of society and the well-known historical types of State and Law, each legal system possessing its legislative peculiarities, so that its assessment from the The perspective of comparative law offers us a more complete vision of it and the possibility of valuing different assessments through the prism of doctrinal and jurisprudence thinking. As Cobo del Rosal and Vives Antón point out: "Those who voluntarily place themselves in situations of unimputability to carry out the crime are already beginning their execution, and if that is the case, in the case of the actio liberae in causa dolosa, no there is a dissociation between the moment of action and the moment of imputability. " The basis of this idea falls on the statement of prominent jurists such as Von Lizst, Carrara and Maurach that indicate that knowingly placing oneself in a situation of unimpeachable means becoming an instrument of crime itself. In the same way that the imputable subjects use the unimputable to achieve their criminal purposes by becoming mediate authors, the former can also use themselves and commit crimes in the same way. The subject who is expressly placed in transitory mental disorder, is in fact catalyzing the illicit nature of their behavior. The free actions in their cause can be raised in the cases of drunkenness and sleep and they can not only be fraudulent but guilty, there are different criteria around their punishment being the most widespread which considers that these already exist at the beginning of execution of the conduct that is prosecuted.
This does not mean that there are not many contrary opinions and arguments that the theory of actio liberae in causa can harm the principle of culpability and even legality, considering the need for the subject to be imputable also at the time of realization the fact. Thus, the impossibility of referring guilt to that moment has led to contradictions with dogmatic principles and various authors have pronounced in order to achieve a coordination between the above and the possibility of imposing a penalty.
For its part, SAINZ CANTERO states: "The dominant doctrine is inclined in these cases to bring back the moment of the imputability to the one in which the cause was placed (the triggering action or omission), understanding that if in that time the subject of the action was imputable, we must have it as such, even if it were not, in the execution of the typical behavior ". However, in the opinion of BAJO FERNANDEZ: "The problem of coexistence between the theory of the actio liberae in causa and the dogmatic principles is only apparent." And to give grounds for this assertion, among other arguments, it refers to the fact that posed that there is a similar way of acting between the person who places a bomb and activating a certain mechanism makes it explode hours later and who "predisposes his own power of corporal action to act when the mind is in a state of unconsciousness". And continues: "Indeed this is so, but while the first assumption is explained because there is already a typical act of execution of the act to place the bomb, the second is not done with that circumstance, which requires an explanation of his punishment." Simply attending to reasons of material justice most of the legislations do not accept the exemption in such cases.

COBO DEL ROSAL, M Y VIVES ANTON,  T.S.: Derecho Penal, parte general, quinta edición, Valencia, 1999, pág. 243.

SAINZ CANTERO, J.A.: Lecciones de Derecho penal, Tomo III, parte general, Culpabilidad. Punibilidad. Formas de aparición, Madrid, 1985, pág.31

JAKOBS, G.: Derecho Penal. Parte General. Fundamentos y teoría de la imputación.  Trad. Joaquín Cuello Contreras y José Luis Serrano González de Murillo,  Madrid. 1995, pág. 630.

MIR PUIG, S.: Derecho penal, parte general, quinta edición,    Barcelona, 1998, pág.  586.

MUÑOZ CONDE, F. y GARCIA ARAN, M.: Derecho penal, parte general,  tercera edición, revisada y puesta al día conforme al Código penal  de 1995, Valencia, 1998., pág. 389.

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Some historic considerations on democracy

 Democracy was born in the city-states of classical Greece, in the fifth century BC. It reached its most complete form in the city of Athens, in the time of Pericles. The characteristics of Greek democracy are those that come closest to the ideal of direct democracy, in which the group of citizens participates directly and continuously in making decisions about the affairs of the community. However, from an institutional perspective, it is a very simple and primitive construction.

In Athens the citizens met several times a year, it is estimated that at least 40, on the hill of Pnyx to discuss the affairs of the community. The agenda of discussions was established by the "Committee of 50", constituted by members of a "Committee of the 500", representatives, in turn, of the hundred demes that made up the city. The period of public office was very short (less than two months in the "Committee of 50", one year in the "Committee of 500") and the designation was made by lottery methods in the first case and rotation In a second. The discussion and deliberation among citizens formed the basis of this system of democratic participation. Decisions were made, normally, by way of consensus, and at the time of the apogee of the system in Athens a quorum of 6,000 participants was required for the decisions of the assembly to be valid. All this gave rise to a kind of "democracy without a State".

Direct democracy, as practiced in Athens, requires very special conditions of development, which have not occurred again in history. The citizen was a total figure, whose identity did not admit distinction between the public and private spheres: political life appeared as a natural extension of being itself. The interests of citizens were harmonious, a phenomenon typical of a homogeneous society that, moreover, had a small size, which favored direct relations between all. In classical Greece the existence of a wide stratum of slaves was a fundamental condition for the functioning of direct democracy. Thus, citizens were able to meet frequently to decide directly on laws and policy measures.

As Giovanni Sartori points out, after the decline of Greek democracy, the word democracy practically disappeared for a period of 2,000 years. They spoke rather of public res. In Rome, for example, the idea of ​​mixed government was introduced, which represented diverse interests or groups that constituted the community. The system quickly adopted oligarchical features (government of a few), in which the formal commitment of popular participation resulted in a very limited capacity for control.

The expansion and consolidation of Christianity in the Western world displaced political reflection towards the universe of theology: the issue of political participation ceased to be a concern for more than a millennium. In the Middle Ages it reappeared in a different form that, at the time, had little to do with democracy. In several European countries, monarchs, urged by economic needs, called assemblies to deal with matters of State, fundamentally associated with the lifting of taxes and warmongering companies. The members of these assemblies very loosely represented the estates that made up the kingdom: the nobility, the clergy and the bourgeoisie.

From there arose the idea of ​​responsibility of the monarch before some of his subjects; This was the beginning of what is now known as Parliament. In England, in the fourteenth century, Parliament forced the king to sacrifice ministers to grant subsidies and then to present account statements; in France, Spain and Scandinavia similar phenomena happened. However, with the consolidation of the absolutist monarchies, the parliaments stopped being convened from the seventeenth and eighteenth centuries; England was the exception. Even so, the idea of ​​political representation (effective or not) was beginning to penetrate Western political thought. Its origin was far from democratic, but it provided a solution to the problem of participation in complex political communities of large size.

At the end of the Middle Ages and during the Renaissance great transformations began to take shape, which little by little would return to make political participation an important topic of reflection and a popular demand that centuries later would become more universal. In the social, economic and political spheres there were changes that would have repercussions in the world of values.

Jacques Maritain,  El Hombre y el Estado. 1951.

Dahl, Robert, La democracia y sus críticos. Barcelona, 1992.

Sartori, Giovanni, Teoría de la democracia. vol. 2, Alianza Editorial, México, 1988, Pág. 356.

Duverger, Maurice, Instituciones Políticas y Derecho Constitucional. Ariel, Barcelona, 1980

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Considerations on contraventions and environmental education

The system of abiotic, biotic and socioeconomic elements with which man interacts, while adapting to it, transforming it and using it to satisfy its needs, constitutes the environment. This system has been seriously damaged in recent times by industrial, nuclear and household waste and the use of fossil fuels, refrigerant gases, aerosols and other toxic gases that pollute the atmosphere and causes more and more damage to the ozone layer. After becoming aware of these serious effects on environmental ecosystems, the protection of the environment has become the fundamental premise that attempts to sustain life on earth, protected by the application of all the legislation that exists in this matter; but this alone is not enough, because if we lack the education and knowledge that we need to have to achieve this goal from childhood, if we lack environmental culture and if man does not see himself, in all aspects of life, inserted As regards the environment, the disastrous consequences will be inevitable. To reduce the frequencies of behaviors that affect natural resources, the Cuban State implemented a contraventional system with regard to the environment that allows, on the one hand, to educate citizens and on the other to sanction them if they incur in the figures described.
The analysis of the legislation that regulate the environment regarding contraventions and establish a relationship between them and the necessary environmental education is the objective of this work. A long time ago they knew behaviors that were given a criminal treatment without having a serious connotation in society. These acts were subject to minor penalties because they were less important than crimes or crimes because of the little injury they caused. The first term with which they were known in our country was "criminal misdemeanors" thanks to the Spanish Penal Code of 1870 that recognized them and for them imposed fines and administrative corrections.

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Bacteria and viruses of veterinary medical interest. Etymological analysis

It has been analysed a number of terms related to bacterium and virus of medical and veterinarian interest in order to know their origins and with the expectation that it will lead to a better understanding of the Microbiological terminology. In the case of bacteria, the etymological analysis encompasses to the taxonomic species level, meanwhile for virus it reaches to the family level with some familiar genera.

In bacteria, the genera prefixes are almost always Greek roots or the name modification of researchers related to the bacterium. The suffixes could be Greek or Latin and they refer to the morphological bacteria types. For the species mostly Latin roots are used and they represent geographical characteristics such as host, target organ, etc.

Regarding to virus, the family name has Greek prefixes, whereas the suffixes are always related to virus (viridae) which is a Latin term.

In any case, every living organism studied is given with a brief description about its pathological effects.

We hope the usefulness of this work as teaching material in Microbiological programmes.

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Standardization of the Safety Level of the Use of DMSO in Viability Assays in Bacterial Cells

The antibacterial potential of the most diverse medicinal plants has benefited humanity for centuries, and precisely because of this, the number of studies investigating the antimicrobial activity of essential oils and their components is increasing. However, the hydrophobic character of the essential oils has made the experiments difficult, requiring the use of organic solvents in the tests in order to avoid such complications. Among the most commonly used solvents are dimethylsulfoxide (DMSO / C2H6OS). To date, the literature has not yet determined a standardization of the usual concentration of DMSO suitable for bacterial experiments, so that its use does not check the efficacy of the tested phytoconstituent by interactions between the solvent and the exploited compound. In view of this reality, the present study intends to standardize the DMSO concentrations that do not interfere in the viability of the bacterial strains of Escherichia coli ATCC 25922, Staphylococcus aureus ATCC 25923, Pseudomonas aeruginosa ATCC 27853, Proteus mirabilis ATCC 25922 and Enterococcus faecalis ATCC 29212. In order to reach this objective, the disc diffusion method in Müller Hinton Agar of a reagent impregnated on a filter paper disc was used, using different concentrations of DMSO to determine the minimum inhibitory concentration (MIC) of the five microorganisms listed. The experiment was carried out in triplicate in order to safeguard the effectiveness of the method tested. The incubation was done in an oven at 35º C, for a period of 24 hours. For the test method the conclusions of the tests performed were expressed by the arithmetic mean of the diameter of the inhibition halos formed around the disks. The test demonstrates that for the concentrations and microorganisms tested, DMSO provides safety in its use.

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Mosquito-borne viruses: A computational search for antiviral drugs

Mosquito-borne viruses of Flaviviridae virus family are dangerous for human. To develop drugs and vaccines and drugs against Flaviviridae viruses, promising targets must be identified.

The genomes and biochemistry of Yellow fever (YFV), West Nile (WNV), and Zika (ZIKV) viruses are similar. Therefore, the main aim of this project was to identify lead compounds which could simultaneously inhibit all three viruses targeting one or more viral proteins. Activation of non-structural proteins NS1, NS2A, NS3 and NS5 inside of mosquito-borne viruses is necessary for virial replication, as well as structural envelope E is responsible for entry of viral particles into the cell. Hence, the inhibition of at least one type of protein could neutralize the entire virus.

RCSB Protein Data Bank (https://www.rcsb.org/) was used to extracted data on sequences variations for 10 target proteins: structural envelope (E), non-structural hydrolase and transferase for YFV, non-structural hydrolase and methyltransferase for WNV and non-structural methyltransferase, helicase, protease RNA-dependent polymerase and structural envelope for ZIKV. These proteins contained bonded ligands, so locations of these ligands were used as a reference for initial search of possible binding pockets. In addition to it, allosteric sites binding were analyzed.

At the first step, BLAST online tool was applied to find similarity between studied proteins of YFV, WNV, and ZIKV. While genomes of YFV, WNV, and ZIKV are quite similar, the qualitative analysis of developed models revealed, that the best binding sites for promising hits were located in different places for same types of proteins. Using BLAST tool it was found, that in some cases differences are drastic. For instance, similarities between non-structural NS1 proteins were: ~ 55 % for ZIKA and DENV, ~50 % for ZIKA and YFV, ~ 55 % for ZIKA and WNV, ~ 45 % for YFV and DENV, ~ 45 % for YFV and WNV, and ~ 50 % for DNV and WNV. 

A series of FDA approved drugs from Binding database (https://www.bindingdb.org) and DrugBank (http://www.drugbank.ca/drugs) were screened. Molecular docking was performed for more than 6000 drug-like compounds. The active sites of the enzymes were defined to include residues within 8.5 Å radius around inhibitor. Both crystallography-based and suggested allosteric sites were considered for docking. Final scores were used for database ranking.

The best pose with the highest score was selected to analyze the interactions between ligand and protein. Results were compared with literature data and some additional drugs (such as niclosamide and berberine) were added to the list of hits. At the next step, hits were used as references for deeper screening of ZINK database. Free energies of binding varied from −35 kJ/mol to -6 kJ/mol for hits.

A series of compounds were identified as inhibitors for proteins of certain type. For example, quinacrine and its derivatives acted in the same way against all nonstructural NS3 proteins. Another examples are nanchangmycin and lovastatin, that interacted with allosteric sites of NS2A and NS3 proteins. Specific poses were identified and analyzed. For instance, in the case of Zika, selected drugs mainly bonded to Glu234, Gln396, and Glu 231 inside of NS3 protein.

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