Analysis of Simulated Output Characteristics of Gas Sensor Based on Graphene Nanoribbon

This work presents simulated output characteristics of gas sensor transistors based on graphene nanoribbon (GNRFET). The device studied in this work is a new generation of gas sensing devices, which are easy to use, ultracompact, ultrasensitive, and highly selective. We will explain how the exposure to the gas changes the conductivity of graphene nanoribbon. The equations of the GNRFET gas sensor model include the Poisson equation in the weak nonlocality approximation with proposed sensing parameters. As we have developed this model as a platform for a gas detection sensor, we will analyze the current-voltage characteristics after exposure of the GNRFET nanosensor device to NH3 gas. A sensitivity of nearly 2.7% was indicated in our sensor device after exposure of 1 ppm of NH3. The given results make GNRFET the right candidate for use in gas sensing/measuring appliances. Thus, we will investigate the effect of the channel length on the ON- and OFF-current

Efecto de procesos de ahumado frío y caliente y la adición de extracto polifenólico natural de Dunaliella salina sobre la calidad bioquímica y la vida útil de filetes de Sander lucioperca almacenados durante 90 días

The effects of cold and hot smoking and the addition of Dunaliella salina polyphenol extract on the biochemical quality and shelf-life of Sander lucioperca fillets after storage for 90 days at 0-4 °C were examined. The results showed a significant increase in protein, lipid, free fatty acid, and 1,1-diphenyl-2-picrylhydrazyl contents, and a decrease in peroxide and thiobarbituric acid reactive substances, and volatile base nitrogen levels in cold (CSF) and hot (HSF) smoked fillets covered with or without extract and stored for 1, 20, and 90 days compared to fresh fillets (FF). Saturated and monounsaturated fatty acids exhibited a significant increase in FF and CSF and HSF covered with or without extract. The total polyunsaturated fatty acids revealed a significant decrease in FF and CSF and HSF with or without extract. Therefore, cold and hot smoking and polyphenol extract improved the biochemical quality and storage shelf-life of fillets for 90 days at 0-4 °C.Se examinaron los efectos del ahumado en frío y en caliente y la adición de extracto de polifenoles de Dunaliella salina sobre la calidad bioquímica y la vida útil de filetes de Sander lucioperca almacenados durante 90 días a 0-4 °C. Los resultados mostraron un aumento significativo en los contenidos de proteínas, lípidos, ácidos grasos libres y 1,1-difenil-2-picrilhidrazilo, y una disminución en las sustancias reactivas de peróxido y ácido tiobarbitúrico, y los niveles de nitrógeno básico volátil en frío (LCR) y caliente (HSF) de filetes ahumados cubiertos con o sin extracto y almacenados durante 1, 20 y 90 días en comparación con los filetes frescos (FF). Los ácidos grasos saturados y monoinsaturados exhibieron un aumento significativo en FF y LCR y HSF cubiertos con o sin extracto. Los ácidos grasos poliinsaturados totales revelaron una disminución significativa en FF y CSF y HSF con o sin extracto. Por lo tanto, el ahumado en frío y en caliente y el extracto de polifenoles mejoraron la calidad bioquímica y la vida útil durante el almacenamiento de los filetes durante 90 días a 0-4 °C

Hereditary breast cancer in Middle Eastern and North African (MENA) populations: identification of novel, recurrent and founder BRCA1 mutations in the Tunisian population

Germ-line mutations in BRCA1 breast cancer susceptibility gene account for a large proportion of hereditary breast cancer families and show considerable ethnic and geographical variations. The contribution of BRCA1 mutations to hereditary breast cancer has not yet been thoroughly investigated in Middle Eastern and North African populations. In this study, 16 Tunisian high-risk breast cancer families were screened for germline mutations in the entire BRCA1 coding region and exon–intron boundaries using direct sequencing. Six families were found to carry BRCA1 mutations with a prevalence of 37.5%. Four different deleterious mutations were detected. Three truncating mutations were previously described: c.798_799delTT (916 delTT), c.3331_3334delCAAG (3450 delCAAG), c.5266dupC (5382 insC) and one splice site mutation which seems to be specific to the Tunisian population: c.212 + 2insG (IVS5 + 2insG). We also identified 15 variants of unknown clinical significance. The c.798_799delTT mutation occurred at an 18% frequency and was shared by three apparently unrelated families. Analyzing five microsatellite markers in and flanking the BRCA1 locus showed a common haplotype associated with this mutation. This suggests that the c.798_799delTT mutation is a Tunisian founder mutation. Our findings indicate that the Tunisian population has a spectrum of prevalent BRCA1 mutations, some of which appear as recurrent and founding mutations

Venezuela e ALBA: regionalismo contra-hegemônico e ensino superior para todos

Partindo de um quadro teórico neo-gramsciano crítico à globalização, este artigo aplica a nova teoria do regionalismo (NTR) e a teoria do regionalismo regulatório (TRR) à sua análise e teorização dos tratados de comércio da Aliança Bolivariana para os Povos da Nossa América (ALBA-TCP) como regionalismo contra-hegemônico na América Latina e Caribe (ALC). A ALBA está centrada na ideia de um Socialismo do Século XXI, que, como (inicialmente) também a Revolução Bolivariana da Venezuela, substitui a 'vantagem competitiva' pela 'vantagem cooperativa'. Em seu caráter de conjunto de processos multidimensionais e transnacionais a ALBA-TCP opera dentro de/transversalmente a um número de setores e escalas, ao mesmo passo que as transformações estruturais são movidas pela interação de agentes do Estado e agentes não estatais. A política de Educação Superior para Todos (ESPT) do governo venezuelano rejeita a agenda neoliberal globalizada de mercadorização, privatização e elitismo e reinvindica educação pública gratuita em todos os níveis como um direito humano fundamental. A ESPT está sendo regionalizado em um espaço educacional emergente da ALBA e assume um papel-chave nos processos de democracia direta e participatória, dos quais a construção popular (bottom-up) da contra-hegemonia e a redefinição política e econômica da ALC dependem. Antes de produzir sujeitos empreendedores conformes ao capitalismo global, a ESPT procura formar subjetividades ao longo de valores morais de solidariedade e cooperação. Isso será ilustrado com referência a um estudo etnográfico de caso da Universidade Bolivariana da Venezuela (UBV).This paper employs new regionalism theory and regulatory regionalism theory in its analysis and theorisation of the Bolivarian Alliance for the Peoples of Our America (ALBA) as a counter-hegemonic Latin American and Caribbean (LAC) regionalism. As (initially) the regionalisation of Venezuela's Bolivarian Revolution, ALBA is centred around the idea of a 21st Century Socialism that replaces the 'competitive advantage' with the 'cooperative advantage'. ALBA, as a set of multi-dimensional inter- and transnational processes, operates within and across a range of sectors and scales whilst the structural transformations are driven by the interplay of state and non-state actors. The Venezuelan government's Higher Education For All (HEFA) policy, which is being regionalised within an emergent ALBA education space, assumes a key role in the direct democratic and participatory democratic processes upon which a bottom-up construction of counter-hegemony depends. HEFA challenges the globalised neoliberal higher education agenda of commoditisation, privatisation and elitism. Rather than producing enterprising subjects fashioned for global capitalism, HEFA seeks to form subjectivities along the moral values of solidarity and cooperation

Emirati Students' experiences of English as a medium of instruction

The English language has become the medium ofinstruction (EMI) in higher educational institutions in the United Arab Emirates (UAE). The main purpose of this project is to explore and investigate what Emirati university students think of EMI. In particular we investigated the effects EMI has on their educational achievement and learning experiences. The study also revealed students' views about the status of Arabic as a language ofinstruction at the tertiary level and the possibility of a dual language education. An exploratory research strategy with qualitative data obtained through semi-structured interviews revealed that students' experiences with EMI at the university level were shaped by a number ofeducational and sociocultural factors. The nature of the primary and secondary school experience and the students' overall competence in English has to a large extent formed their views of EM!. Students who attended private English-medium schools were much more prepared to face the academic demands of EMI than their colleagues who learned English as a foreign language and a subject among others in the curriculum of the government primary and secondary schools. Family background and parental attitudes towards English have also played a role in students' acceptance ofEMI and in many cases a tendency to prefer English to Arabic. However, the data did reveal that Emirati students were also interested in Arabic as a medium ofinstruction for a number ofuniversity subjects. Thinking ofemployability and market forces, the students had a realistic if not a pragmatic attitude towards Arabic. They also, as expected, associated Arabic with discourses ofidentity, linguistic, and cultural heritage. One major implication ofthis study is the inadequacy of the old binary division between Arabic and English as languages ofinstruction. The study challenges established discourses that have been reinforcing English as a language ofscience and academia while relegating Arabic to a language of heritage and religion. Arabic and English can mutually co-exist in a model ofdual language instruction for university students

Concept of new photodetector based on single electron transistor for single charge detection

In this paper, we present a model proposition of photo-SET (single electron photo-detector) aiming at detecting one by one electrons. In the first part of this work, we present the two blocs of the proposed photo-SET (reading and detection blocs). The device structure presented is consisting of two SETs capacitively coupled. In this model, the first SET (SET1) is supposed to read the charge whereas the detection bloc is represented by the second SET (SET2). In the second part, we investigate the effects of photoexcitation on Id-Vg curves and we present results obtained on the output photo-SET characteristics after variation of power illumination and response time

Study of photogenerated traps in nanopixels by random telegraph signal and low frequency noise

In this work, we present noise analysis in a Single Electron Photo-detector (photo-SET or nanopixel) able to detect one by one electron. We perform the power spectral densities (PSD) of random telegraph signals (RTSs) measured in the dark conditions and under light illumination. Photoinduced RTS can be attributed to the charging of a dot near the current path. From these results, photogenerated traps were identified. It is also found that RTS fluctuations depend on the light wavelength