In vitro ruminal fermentation, nutritional evaluation and antioxidant activity of some forest shrubs of North West Tunisia for goats

Chemical composition and characteristics of in vitro fermentation were determined for two shrubs (Genista aspalathoides and Rhamnus alaternus) collected from north western Tunisia. The primary and secondary chemical composition was determined and in vitro fermentation parameters were measured in 100 ml glass syringes for 48 hours to determine gas production. There are significant differences in chemical and wall composition for the two shrubs studied (p < 0.05). Rhamnus alaternus is richer in secondary metabolites (59.2 mg GAE / g DM) than Genista aspalathoides and has the highest content of crude protein (CP). Genista aspalathoides had the lowest anti-radical activity since it has the highest levels of secondary metabolites, so it is the most digestible species with the highest value of gas production after 24 hours incubation and released more methane than Rhamnus alaternus. Keywords: Shrub, Chemical composition, in vitro fermentation, antioxidant activity, methan

Effects of total replacement of soybean meal and corn on ruminal fermentation, volatile fatty acids, protozoa concentration, and gas production

The main purpose of this study is to evaluate the effect of total replacement of soybean meal and corn with triticale and faba bean or field pea on rumen fermentation, protozoa counts, and gas production of lactating ewes. A total of 30 Sicilo-Sarde ewes were randomly allocated into three groups and were fed 1.8 kg drymatter of oat hay plus 500 g of one of three concentrates: the first concentrate (CS) was mainly composed of soybean meal, corn, and barley; the second (TFB) was formed by triticale and faba bean; and the third (TFP) was composed of triticale and field pea. The type of concentrate did not affect ruminal pH or ammonia nitrogen concentration (P > 0.05). The individual concentrations of volatile fatty acids showed a significant interaction between the type of concentrate and sampling time (P 0.05). The cumulative gas production from the in vitro fermentation, the time of incubation, and their interaction was affected by concentrate (P < 0.001). The substitution of soybean meal and corn in the concentrate with faba bean or field peas and triticale might maintain rumen parameters of dairy ewes

Multiple Analytical Approaches Reveal Distinct Gene-Environment Interactions in Smokers and Non Smokers in Lung Cancer

Complex disease such as cancer results from interactions of multiple genetic and environmental factors. Studying these factors singularly cannot explain the underlying pathogenetic mechanism of the disease. Multi-analytical approach, including logistic regression (LR), classification and regression tree (CART) and multifactor dimensionality reduction (MDR), was applied in 188 lung cancer cases and 290 controls to explore high order interactions among xenobiotic metabolizing genes and environmental risk factors. Smoking was identified as the predominant risk factor by all three analytical approaches. Individually, CYP1A1*2A polymorphism was significantly associated with increased lung cancer risk (OR = 1.69;95%CI = 1.11–2.59,p = 0.01), whereas EPHX1 Tyr113His and SULT1A1 Arg213His conferred reduced risk (OR = 0.40;95%CI = 0.25–0.65,p<0.001 and OR = 0.51;95%CI = 0.33–0.78,p = 0.002 respectively). In smokers, EPHX1 Tyr113His and SULT1A1 Arg213His polymorphisms reduced the risk of lung cancer, whereas CYP1A1*2A, CYP1A1*2C and GSTP1 Ile105Val imparted increased risk in non-smokers only. While exploring non-linear interactions through CART analysis, smokers carrying the combination of EPHX1 113TC (Tyr/His), SULT1A1 213GG (Arg/Arg) or AA (His/His) and GSTM1 null genotypes showed the highest risk for lung cancer (OR = 3.73;95%CI = 1.33–10.55,p = 0.006), whereas combined effect of CYP1A1*2A 6235CC or TC, SULT1A1 213GG (Arg/Arg) and betel quid chewing showed maximum risk in non-smokers (OR = 2.93;95%CI = 1.15–7.51,p = 0.01). MDR analysis identified two distinct predictor models for the risk of lung cancer in smokers (tobacco chewing, EPHX1 Tyr113His, and SULT1A1 Arg213His) and non-smokers (CYP1A1*2A, GSTP1 Ile105Val and SULT1A1 Arg213His) with testing balance accuracy (TBA) of 0.6436 and 0.6677 respectively. Interaction entropy interpretations of MDR results showed non-additive interactions of tobacco chewing with SULT1A1 Arg213His and EPHX1 Tyr113His in smokers and SULT1A1 Arg213His with GSTP1 Ile105Val and CYP1A1*2C in nonsmokers. These results identified distinct gene-gene and gene environment interactions in smokers and non-smokers, which confirms the importance of multifactorial interaction in risk assessment of lung cancer

Digital Predistorter Design Using a Reduced Volterra Model to Linearize GaN RF Power Amplifiers

In this paper, a novel method for reducing a Simplified Volterra Series (SVS) model size is proposed for GaN RF Power Amplifier (PA) Digital Predistorter (DPD) design. Using the SVS-modified model, the number of coefficients needed for the PA behavioral modeling and predistortion can be reduced by 60 % while maintaining acceptable performances. Simulation and implementation tests are performed for a Class AB GaN PA and Doherty GaN PA using a 20-MHz Long Term Evolution-Advanced (LTE-A) signal. The Adjacent Channel Power Ratio (ACPR) attains -40 dB and -41 dB for the Doherty and Class AB GaN PAs, respectively. The implementation complexity is also studied and the obtained results prove the capability of the proposed model to linearize PA using 3% of the Slice LUTs and 87% of the DSP48E1 available in the Xilinx Zynq-7000 FPGA

First report of Penicillium ulaiense causing whisker mould on stored citrus fruit in Tunisia

In a survey carried out in January-July 2014, fruits showing blue and/or green efflorescence, were picked in farms and packinghouses of the northeastern part of Cap Bon peninsula, and brought to the laboratory. On infected fruits P. digitatum and P. italicum coexisted with a morphologically distinct Penicillium spp. This latter was sub-cultured on malt extract agar (MEA) and identified, according to its morphological and cultural characteristics, as P. ulaiense, the causal agent of whisker mould, whose distinctive feature is the ability to form coremia (1-7 mm tall) with white stalks arranged in concentric circles or circular patches (Holmes et al., 1994)

Biocontrol of apple postharvest decay by Aureobasidium pullulans

The activity of two biological control agents, strains L1 and L8, previously identified as Aureobasidium pullulans, was tested for the first time in the same experiments on apple, artificially inoculated with Botrytis cinerea (grey mould), Colletotrichum acutatum (bitter rot) or Penicillium expansum (blue mould). The washed cells of antagonists controlled over 86% of three decays and the antagonist L1 seemed more efficient than L8. The cell concentration of both antagonists was highly correlated with their efficacy, the R2 ranging from 0.93 to 0.99. The highest concentration (108 CFU ml-1) of L1 and L8 provided the best control of B. cinerea, C. acutatum and P. expansum, although gray mould was completely inhibited also by a concentration one log lower (107 CFU ml-1). The population dynamic of L1 and L8 strains in ‘Gala’ apple increased almost eightfold during the first 48 h after treatment and remained elevated until 7 days, revealing that, although antagonists were isolated from carposhere of peach fruit, they showed good adaptation in other wound environments such as apple, making them suitable for pathogen control in a wide range of hosts. Preliminary in vitro trials were conducted in order to investigate the mechanisms of action of L1 and L8 strains. Both the washed cells showed a complete control of all three pathogens, while the culture filtrates and autoclaved cells were found to have had no significant inhibition on pathogens. In a dual culture dish assay, where there was neither physical contact between antagonists and pathogens nor fungal diffusion through the culture medium, the antifungal effects observed on pathogen mycelium growth could be attributed to the production of volatile organic compounds (VOCs) generated by the antagonists. The VOCs significantly inhibited the growth of all three tested pathogens compared to the control, albeit with a different rate. L1 strain also showed a curative effect; indeed when an antagonist-based-treatment was carried out twelve hours from inoculum, the incidence of blue mould and bitter rot was reduced by 38% and 50% respectively, while the greatest inhibition of grey mould was observed when fruit were treated with the antagonist six hours from the inoculum. In conclusion, A. pullulans L1 and L8 strains could be considered good candidates for the development of biofungicides for postharvest application in the pomefruit industry