Impact of Non-Stationary Noise on xDSL Systems: an Experimental Analysis

Broadband services require data rates that can only be achieved by using relatively high spectrum frequencies. At such high frequencies, the DSL (Digital Subscriber Line) signal is more susceptible to external noise sources, such as radio frequency interference and impulsive noise. This paper aims to characterize how the impulsive noise impacts on services and applications for a broadband system using an ADSL2+ loop. The first approach was to use the impulsive noise defined in the standards G.996.1 (Test Procedures for DSL Transceivers) from ITU-T and TR-048 (ADSL Interoperability Test Plan) from DSL Forum. In this approach we have also used a HDSL (High Bit Rate DSL) and white noise disturbers on the line. The impulsive noises c1 and c2 (defined in G.996.1) are injected into the circuit at the CO (Central Office) end and CPE (Customer Premises Equipment) end of the loop simulator. Additionally, it was analyzed the spikes of noise's impact on the ADSL2+ line. In this case, pre-defined models of NEXT (Near-end crosstalk) and white noise are injected on CO and CPE side, simultaneously. Metrics like packet rate, lost packet count, bandwidth, short-term average transfer delay, and errored seconds are used to characterize the DSL loop under the noise impairments

Qualidade de mudas de alface em função de substratos com e sem biofertilizante Quality of lettuce seedlings depending on substrates with and without biofertilizer addition

Avaliou-se a qualidade de mudas de alface em função de substratos com e sem biofertilizante (aplicado aos 6; 12 e 18 dias após germinação) em condições de casa-de-vegetação. O experimento foi conduzido em esquema fatorial inteiramente casualizado: 3 cultivares (Babá-de-Verão, Grand Rapids e Grandes Lagos) x 3 tipos de substratos (areia lavada, composto orgânico e substrato comercial Plantmax®) x 2 (com e sem biofertilizante), com quatro repetições. A avaliação foi feita aos 24 dias da germinação através de número de folhas, altura da parte aérea, comprimento da raiz, massa seca da parte aérea e massa seca da raiz. Houve efeito isolado dos fatores cultivares e substratos para número de folhas e comprimento da raiz. Houve efeito de interação cultivares x substratos para altura da parte aérea, massa seca da parte aérea e massa seca da raiz. Dentre as variáveis analisadas a cultivar Grand Rapids e o substrato composto orgânico foi a que obteve melhor resultado. Não houve influência significativa da aplicação de biofertilizante.<br>The quality of lettuce seedlings depending on substrates and biofertilizer addition (at 6; 12 and 18 days after germination), under greenhouse conditions was evaluated. The experiment was carried out in a completely randomized factorial scheme: 3 cultivars (Babá-de-Verão, Grand Rapids and Great Lakes) x 3 substrates (washed sand, organic compost and commercial substrate Plantmax®) x 2 (with and without biofertilizer addition), with four replications. The evaluation was done on 24-day old seedlings through number of leaves, shoot height, root length, shoot dry mass and root dry mass. There was an isolated effect for cultivars and substrates with regard to the number of leaves and root length. There was cultivars x substrates interaction effect for shoot height, shoot dry mass and root dry mass. The best result was obtained with cultivar Grands Rapids grown in organic compost. There were no significant effects of biofertilizer addition with respect to the evaluated variables

Antibiotics in the clinical pipeline in 2013

The continued emergence of multi-drug-resistant bacteria is a major public health concern. The identification and development of new antibiotics, especially those with new modes of action, is imperative to help treat these infections. This review lists the 22 new antibiotics launched since 2000 and details the two first-in-class antibiotics, fidaxomicin (1) and bedaquiline (2), launched in 2011 and 2012, respectively. The development status, mode of action, spectra of activity, historical discovery and origin of the drug pharmacophore (natural product, natural product derived, synthetic or protein/mammalian peptide) of the 49 compounds and 6 β-lactamase/β-lactam combinations in active clinical development are discussed, as well as compounds that have been discontinued from clinical development since 2011. New antibacterial pharmacophore templates are also reviewed and analyzed