A 2.5MHz bandpass active complex filter With 2.4MHz bandwidth for wireless communications

This paper presents a fully differential 8thorder transconductor-based active complex filter with 2.4MHz bandwidth and centered at 2.5MHz, designed in a 90nm 2.5V 7M and MIM capacitors CMOS process technology. The filter compliants with the requirements of the IEEE802.15.4 standard. Simulation results including mismatching and process variations over the extracted view of the circuit are shown. The filter has a nominal gain of 12dB, good selectivity (20dB@2MHz offset), high image rejection (51dB nominal) and low power consumption (3.6mA @2.5V).Junta de Andalucía TIC-927Gobierno de España TEC2007-6807

Latex peptidases of Calotropis procera for dehairing of leather as an alternative to environmentally toxic sodium sulfide treatment

Dehairing of crude leather is a critical stage performed at the beginning of its processing to obtain industrially useful pieces. Tanneries traditionally apply a chemical process based on sodium sulfide. Since this chemical reactive is environmentally toxic and inefficiently recycled, innovative protocols for reducing or eliminating its use in leather depilation are welcomed. Therefore, latex peptidases from Calotropis procera (CpLP) and Cryptostegia grandiflora (CgLP) were assayed for this purpose. Enzyme activity on substrates representative of skin such as hide powder azure (UHPA), elastin (UE), azocollagen (UAZOCOL), keratin (UK), and epidermis (UEP) was determined, while depilation activity was assayed on cow hide. Only CpLP was active against keratin (13.4 UK) and only CgLP was active against elastin (0.12 UE). CpLP (93.0 UHPA, 403.6 UAZOCOL, 36.3 UEP) showed higher activity against the other substrates than CgLP (47.6 UHPA, 261.5 UAZOCOL, 8.5 UEP). In pilot assays, CpLP (0.05% w/v with sodium sulfite 0.6% w/v as activator) released hairs from cow hide pieces. Macroscopic and microscopic analyses of the hide revealed that the dehairing process was complete and the leather structure was preserved. The proteolytic system of C. procera is a suitable bioresources to be exploited by tanneries.Fil: Lopez, Laura Maria Isabel. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Industrial. Centro de Investigación y Desarrollo del Cuero. Provincia de Buenos Aires. Gobernación. Comision de Investigaciones Centíficas. Centro de Investigación y Desarrollo del Cuero; ArgentinaFil: Viana, Carolina A.. Universidade Estadual Do Ceara; BrasilFil: Errasti, María Eugenia. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Industrial. Centro de Investigación y Desarrollo del Cuero. Provincia de Buenos Aires. Gobernación. Comision de Investigaciones Centíficas. Centro de Investigación y Desarrollo del Cuero; ArgentinaFil: Garro, María Laura. Instituto Nacional de Tecnología Industrial. Centro de Investigación y Desarrollo del Cuero. Provincia de Buenos Aires. Gobernación. Comision de Investigaciones Centíficas. Centro de Investigación y Desarrollo del Cuero; ArgentinaFil: Martegani, José Eduardo. Instituto Nacional de Tecnología Industrial. Centro de Investigación y Desarrollo del Cuero. Provincia de Buenos Aires. Gobernación. Comision de Investigaciones Centíficas. Centro de Investigación y Desarrollo del Cuero; ArgentinaFil: Mazzilli, German Ariel. Instituto Nacional de Tecnología Industrial. Centro de Investigación y Desarrollo del Cuero. Provincia de Buenos Aires. Gobernación. Comision de Investigaciones Centíficas. Centro de Investigación y Desarrollo del Cuero; ArgentinaFil: Freitas, Cléverson D. T.. Universidade Estadual Do Ceara; BrasilFil: Araújo, Ídila M. S.. EMBRAPA Agrotropical; BrasilFil: da Silva, Rafaela O.. Universidade Estadual Do Ceara; BrasilFil: Ramos, Márcio V.. Universidade Estadual Do Ceara; Brasi

Performance evaluation of aerobic reactor and Sarcocornia perennis to reduce the COD and chloride of effluents from tanning sheepskins

Tannery is an industry that generates wastewater characterised by high levels of organic matter, chrome, dissolved solids, sulphides and high salinity. The aim of this work was to evaluate at laboratory scale, the decrease of chemical oxygen demand (COD) and salinity from effluents from tanning sheepskins, using physical chemical methods in primary treatment, and bioreactor and wetlands for secondary and tertiary treatment, respectively. Effluents were collected from tanning processes of sheepskins carried out on the Center of Research and Technology on leather tannery plant, La Plata, Argentina. Conventional primary treatments selecting coagulants and flocculants were employed. For secondary treatment, batch bioreactors were designed, and the maximum COD removal was 60-70%. For the tertiary treatment, wetlands at laboratory scale were employed. In this test wetlands were filled with granite stone, with and without the plant Sarcocornia perennis, and COD decreased on average by 64% additional and chlorides concentration decreased by around 15%.Fil: Cortizo, Lorena. Instituto Nacional de Tecnología Industrial. Centro de Investigación y Desarrollo del Cuero. Provincia de Buenos Aires. Gobernación. Comision de Investigaciones Centíficas. Centro de Investigación y Desarrollo del Cuero; ArgentinaFil: Scelsio, Natalia Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Bioquímicas de La Plata "Prof. Dr. Rodolfo R. Brenner". Universidad Nacional de la Plata. Facultad de Ciencias Médicas. Instituto de Investigaciones Bioquímicas de La Plata ; ArgentinaFil: Perotti, Sergio. Instituto Nacional de Tecnología Industrial. Centro de Investigación y Desarrollo del Cuero. Provincia de Buenos Aires. Gobernación. Comision de Investigaciones Centíficas. Centro de Investigación y Desarrollo del Cuero; ArgentinaFil: Martegani, José Eduardo. Instituto Nacional de Tecnología Industrial. Centro de Investigación y Desarrollo del Cuero. Provincia de Buenos Aires. Gobernación. Comision de Investigaciones Centíficas. Centro de Investigación y Desarrollo del Cuero; ArgentinaFil: Lopez, Laura Maria Isabel. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Industrial. Centro de Investigación y Desarrollo del Cuero. Provincia de Buenos Aires. Gobernación. Comision de Investigaciones Centíficas. Centro de Investigación y Desarrollo del Cuero; Argentin

Tanning of Goatskin Using Wheat Bran in the Process of Purging

In the leather technology the use of enzymes with proteolytic activity in the process of bating allows an appropriate structural relaxation to make a leather pliable. This paper has tested the wheat bran as enzymatic agent in the process of purging. The results establish that should not be separated from the solid material bran because it retains most of the enzymatic activity and therefore the total bran suspension must be in contact with the skin to be treated. This enzyme preparation was able to degrade proteins and casein dust skin substrate but not to elastin. Through microscopy techniques it was evidenced opening (relaxation) and the division of the fibrous bundles in the central part of "corium" in the skin samples subjected to treatment with bran. The organoleptic characteristics of the leathers were better than those who had no enzyme treatment (white), while the physical-mechanical tests showed no significant differences. The use of wheat bran may have relevance for artisanal tanneries to replace imported commercial enzyme preparations and use as a by-product of wheat flour industry.Fil: Martegani, José Eduardo. Instituto Nacional de Tecnología Industrial. Centro de Investigación y Desarrollo del Cuero. Provincia de Buenos Aires. Gobernación. Comision de Investigaciones Centíficas. Centro de Investigación y Desarrollo del Cuero; ArgentinaFil: Mazzilli, German Ariel. Instituto Nacional de Tecnología Industrial. Centro de Investigación y Desarrollo del Cuero. Provincia de Buenos Aires. Gobernación. Comision de Investigaciones Centíficas. Centro de Investigación y Desarrollo del Cuero; ArgentinaFil: Nuñez, Gabriela. Instituto Nacional de Tecnología Industrial. Centro de Investigación y Desarrollo del Cuero. Provincia de Buenos Aires. Gobernación. Comision de Investigaciones Centíficas. Centro de Investigación y Desarrollo del Cuero; ArgentinaFil: Marcos, Escola. Instituto Nacional de Tecnología Industrial. Centro de Investigación y Desarrollo del Cuero. Provincia de Buenos Aires. Gobernación. Comision de Investigaciones Centíficas. Centro de Investigación y Desarrollo del Cuero; ArgentinaFil: Esterelles, Gabriela. Instituto Nacional de Tecnología Industrial. Centro de Investigación y Desarrollo del Cuero. Provincia de Buenos Aires. Gobernación. Comision de Investigaciones Centíficas. Centro de Investigación y Desarrollo del Cuero; ArgentinaFil: Bonfranceschi Barros, Alfonsina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Industrial. Centro de Investigación y Desarrollo del Cuero. Provincia de Buenos Aires. Gobernación. Comision de Investigaciones Centíficas. Centro de Investigación y Desarrollo del Cuero; ArgentinaFil: Markán, Juan Alejandro. Instituto Nacional de Tecnología Industrial. Centro de Investigación y Desarrollo del Cuero. Provincia de Buenos Aires. Gobernación. Comision de Investigaciones Centíficas. Centro de Investigación y Desarrollo del Cuero; ArgentinaFil: Lopez, Laura Maria Isabel. Instituto Nacional de Tecnología Industrial. Centro de Investigación y Desarrollo del Cuero. Provincia de Buenos Aires. Gobernación. Comision de Investigaciones Centíficas. Centro de Investigación y Desarrollo del Cuero; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

The involvement of calcium carriers and of the vacuole in the glucose-induced calcium signaling and activation of the plasma membrane H+-ATPase in Saccharomyces cerevisiae cells.

Previous work from our laboratories demonstrated that the sugar-induced activation of plasma membrane H+-ATPase in Saccharomyces cerevisiae is dependent on calcium metabolism with the contribution of calcium influx from external medium. Our results demonstrate that a glucose-induced calcium (GIC) transporter, a new and still unidentified calcium carrier, sensitive to nifedipine and gadolinium and activated by glucose addition, seems to be partially involved in the glucose-induced activation of the plasma membrane H+-ATPase. On the other hand, the importance of calcium carriers that can release calcium from internal stores was analyzed in glucose-induced calcium signaling and activation of plasma membrane H+-ATPase, in experimental conditions presenting very low external calcium concentrations. Therefore the aim was also to investigate how the vacuole, through the participation of both Ca2+-ATPase Pmc1 and the TRP homologue calcium channel Yvc1 (respectively, encoded by the genes PMC1 and YVC1) contributes to control the intracellular calcium availability and the plasma membrane H+-ATPase activation in response to glucose. In strains presenting a single deletion in YVC1 gene or a double deletion in YVC1 and PMC1 genes, both glucose-induced calcium signaling and activation of the H+-ATPase are nearly abolished. These results suggest that Yvc1 calcium channel is an important component of this signal transduction pathway activated in response to glucose addition. We also found that by a still undefined mechanism Yvc1 activation seems to correlate with the changes in the intracellular level of IP3. Taken together, these data demonstrate that glucose addition to yeast cells exposed to low external calcium concentrations affects calcium uptake and the activity of the vacuolar calcium channel Yvc1, contributing to the occurrence of calcium signaling connected to plasma membrane H+-ATPase activation