Estudio de la Flora Vascular de Ilundáin (Navarra).

En este trabajo hemos realizado un estudio de la Flora Vascular presente en Ilundáin (Navarra) en una superficie aproximada de 1.35 km2. Para ello se han recolectado los ejemplares presentes en la zona durante un periodo de tres años (de 1998 a 2001) mediante la realización de herborizaciones de los distintos ambientes, diferenciados por la vegetación dominante de cada uno (robledal, hayedo, pinar, matorral,...) y en las distintas estaciones del año. Así se han recolectado 730 ejemplares pertenecientes a 294 taxones diferentes. Se ha creado un Catálogo Florístico de la zona bajo estudio donde cada taxon está acompañado por información referente a la nomenclatura (sinónimos y nombres vulgares), información biogeográfica (tipo corológico) e información ecológicofuncional (hábitats o ambientes en los que aparece, especies acompañantes, fenología, tipo biológico,...) así como todas las citas tomadas de cada uno de ellos

Clean Development Mechanism Projects in Latin America : beyond reducing CO2 (e) emissions. A case study in Chile

The Clean Development Mechanism (CDM) was created to compensate underdeveloped countries for their contribution to mitigate climate change. Under these rules, those projects showing the lower cost, in terms of investment, for each tonne of CO2 (e) saved, will be the ones selected. However, even if this selection process seems quite rational, it can result in a suboptimal allocation of resources, when other impacts of these projects, also having to do with social welfare, are considered. This point is illustrated in this paper by comparing the financial cost of CER credits of two current CDM projects in Chile, the Santa Marta Landfill Gas Capture Project and the Corneche‐Los Guindos Methane Capture from Swine Manure Project, with that of a third, “virtual” project, the upgrading of the Renca Generation Plant in Santiago de Chile to a gas fired combined cycle (CCGT) Plant. Even if this third project is much less efficient in financial terms, it shows a very important ancillary benefit: its impact on human health. When this impact is introduced, the result, as expected, is a drastic change in the relative social profitability of the three projects

Clean Development Mechanism Projects in Latin America : beyond reducing CO2 (e) emissions. A case study in Chile

The Clean Development Mechanism (CDM) was created to compensate underdeveloped countries for their contribution to mitigate climate change. Under these rules, those projects showing the lower cost, in terms of investment, for each tonne of CO2 (e) saved, will be the ones selected. However, even if this selection process seems quite rational, it can result in a suboptimal allocation of resources, when other impacts of these projects, also having to do with social welfare, are considered. This point is illustrated in this paper by comparing the financial cost of CER credits of two current CDM projects in Chile, the Santa Marta Landfill Gas Capture Project and the Corneche‐Los Guindos Methane Capture from Swine Manure Project, with that of a third, “virtual” project, the upgrading of the Renca Generation Plant in Santiago de Chile to a gas fired combined cycle (CCGT) Plant. Even if this third project is much less efficient in financial terms, it shows a very important ancillary benefit: its impact on human health. When this impact is introduced, the result, as expected, is a drastic change in the relative social profitability of the three projects

Self-synchronized Encryption for Physical Layer in 10Gbps Optical Links

In this work a new self-synchronized encryption method for 10 Gigabit optical links is proposed and developed. Necessary modifications to introduce this kind of encryption in physical layers based on 64b/66b encoding, such as 10GBase-R, have been considered. The proposed scheme encrypts directly the 64b/66b blocks by using a symmetric stream cipher based on an FPE (Format Preserving Encryption) block cipher operating in PSCFB (Pipelined Statistical Cipher Feedback) mode. One of the main novelties in this paper is the security analysis done for this mode. For the first time, an expression for the IND-CPA (Indistinguishability under Chosen-Plaintext Attack) advantage of any adversary over this scheme has been derived. Moreover, it has been concluded that this mode can be considered secure in the same way of traditional modes are. In addition, the overall system has been simulated and implemented in an FPGA (Field Programmable Gate Array). An encrypted optical link has been tested with Ethernet data frames, concluding that it is possible to cipher traffic at this level, getting maximum throughput and hiding traffic pattern from passive eavesdroppers

Self-Synchronized Encryption for Physical Layer in Gigabit Ethernet Optical Links

In this work a new self-synchronized symmetric encryption solution for high speed communication systems necessary to preserve the format of the plaintext is proposed, developed and tested. This new encryption mechanism is based on the block cipher operation mode called PSCFB (Pipelined Statistical Cipher Feedback) and the modulo operation. The confidentiality of this mode is analyzed in terms of its IND-CPA (Indistinguishability under Chosen-Plaintext Attack) advantage, concluding that it can be considered secure in the same way as traditional modes are. The encryption system has been integrated in the physical layer of a 1000Base-X Gigabit Ethernet Interface, where the 8b/10b symbol flow is encrypted at line rate. Moreover, an implementation of the proposed system has been carried out in an FPGA (Field Programmable Gate Array) device. Finally, an encrypted optical link has been tested with real Ethernet frames, getting maximum throughput and protecting the data traffic from passive eavesdroppers

Genotoxicity of silver nanoparticles

Silver nanoparticles (AgNPs) are widely used in diverse sectors such as medicine, food, cosmetics, household items, textiles and electronics. Given the extent of human exposure to AgNPs, information about the toxicological effects of such products is required to ensure their safety. For this reason, we performed a bibliographic review of the genotoxicity studies carried out with AgNPs over the last six years. A total of 43 articles that used well-established standard assays (i.e., in vitro mouse lymphoma assays, in vitro micronucleus tests, in vitro comet assays, in vivo micronucleus tests, in vivo chromosome aberration tests and in vivo comet assays), were selected. The results showed that AgNPs produce genotoxic effects at all DNA damage levels evaluated, in both in vitro and in vivo assays. However, a higher proportion of positive results was obtained in the in vitro studies. Some authors observed that coating and size had an effect on both in vitro and in vivo results. None of the studies included a complete battery of assays, as recommended by ICH and EFSA guidelines, and few of the authors followed OECD guidelines when performing assays. A complete genotoxicological characterization of AgNPs is required for decision-making

Physical Layer Encryption for Industrial Ethernet in Gigabit Optical Links

Industrial Ethernet is a technology widely spread in factory floors and critical infrastructures where a high amount of data need to be collected and transported. Fiber optic networks at gigabit rates fit well with that type of environment, where speed, system performance, and reliability are critical. In this paper, a new encryption method for high-speed optical communications suitable for such kinds of networks is proposed. This new encryption method consists of a symmetric streaming encryption of the 8b/10b data flow at physical coding sublayer level. It is carried out thanks to a format preserving encryption block cipher working in CTR (counter) mode. The overall system has been simulated and implemented in a field programmable gate array. Thanks to experimental results, it can be concluded that it is possible to cipher traffic at this physical level in a secure way. In addition, no overhead is introduced during encryption, getting minimum latency and maximum throughput

A new simple technique for improving the random properties of chaos-based cryptosystems

A new technique for improving the security of chaos-based stream ciphers has been proposed and tested experimentally. This technique manages to improve the randomness properties of the generated keystream by preventing the system to fall into short period cycles due to digitation. In order to test this technique, a stream cipher based on a Skew Tent Map algorithm has been implemented on a Virtex 7 FPGA. The randomness of the keystream generated by this system has been compared to the randomness of the keystream generated by the same system with the proposed randomness-enhancement technique. By subjecting both keystreams to the National Institute of Standards and Technology (NIST) tests, we have proved that our method can considerably improve the randomness of the generated keystreams. In order to incorporate our randomness-enhancement technique, only 41 extra slices have been needed, proving that, apart from effective, this method is also efficient in terms of area and hardware resources

Chaotic Encryption Applied to Optical Ethernet in Industrial Control Systems

In the past decades, Ethernet has become an alternative technology for the field buses traditionally used in industrial control systems and distributed measurement systems. Among different transmission media in Ethernet standards, optical fiber provides the best bandwidth, excellent immunity to electromagnetic interference, and less signal loses than other wired media. Due to the absence of a standard that provides security at the physical layer of optical Ethernet links, the main motivation of this paper is to propose and implement the necessary modifications to introduce encryption in Ethernet 1000Base-X standard. This has consisted of symmetric streaming encryption of the 8b10b symbols flow at physical coding sublayer level, thanks to a keystream generator based on chaotic algorithm. The overall system has been implemented and tested in an field programmable gate array and Ethernet traffic has been encrypted and transmitted over an optical link. The experimental results show that it is possible to cipher traffic at this level and hide the complete Ethernet traffic pattern from passive eavesdroppers. In addition, no space overhead is introduced in data frames during encryption, achieving the maximum throughput

Chaotic Encryption for 10-Gb Ethernet Optical Links

In this paper, a new physical layer encryption method for optical 10-Gb Ethernet links is proposed. Necessary modifications to introduce encryption in Ethernet 10GBase-R standard have been considered. This security enhancement has consisted of a symmetric streaming encryption of the 64b/66b data flow at physical coding sublayer level thanks to two keystream generators based on a chaotic algorithm. The overall system has been implemented and tested in a field programmable gate array. Ethernet traffic has been encrypted, transmitted, and decrypted over a multimode optical link. Experimental results are analyzed concluding that it is possible to cipher traffic at this level and hide the complete Ethernet traffic pattern from any passive eavesdropper. In addition, no overhead is introduced during encryption, getting no losses in the total throughput