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The biosorption efficiency of Cd 2? using rice straw was investigated at room temperature (25 ± 4°C), contact time (2 h) and agitation rate (5 Hz). Experiments studied the effect of three factors, biosorbent dose BD (0.1 and 0.5 g/L), pH (2 and 7) and initial Cd 2? concentration X (10 and 100 mg/L) at two levels ''low'' and ''high''. Results showed that, a variation in X from high to low revealed 31 % increase in the Cd 2? biosorption. However, a discrepancy in pH and BD from low to high achieved 28.60 and 23.61 % increase in the removal of Cd 2? , respectively. From 2 3 factorial design, the effects of BD, pH and X achieved p value equals to 0.2248, 0.1881 and 0.1742, respectively, indicating that the influences are in the order X [ pH [ BD. Similarly, an adaptive neurofuzzy inference system indicated that X is the most influential with training and checking errors of 10.87 and 17.94, respectively. This trend was followed by ''pH'' with training error (15.80) and checking error (17.39), after that BD with training error (16.09) and checking error (16.29). A feed-forward back-propagation neural network with a configuration 3-6-1 achieved correlation (R) of 0.99 (training), 0.82 (validation) and 0.97 (testing). Thus, the proposed network is capable of predicting Cd 2? biosorption with high accuracy, while the most significant variable was X.

Because of exposure to environmental pollutants, infectious agents, and genetic predisposition, companion animals develop respiratory illnesses similar to those in humans. Older dogs of smaller breeds develop canine infectious respiratory disease, chronic bronchitis, and chronic obstructive pulmonary disease, with chronic lung infection, airway goblet cell hyperplasia and metaplasia, and mucus hypersecretion. Excessive mucus clogs airways, reduces gas exchanges, disables the mucociliary clearance, and reduces drug penetration. The Forkhead box protein A2 (FOXA2) is a key transcriptional regulator that maintains airway mucus homeostasis. Prior studies have shown that FOXA2 expression is frequently depleted in diseased human airways. Unfortunately, FOXA2 depletion has not been examined in dogs. Our current study indicated that both single bacterial infection by Pseudomonas aeruginosa and Bordetella bronchiseptica and polymicrobial infection by viral/bacterial pathogens depleted FOXA2 in canine airways, resulting in goblet cell hyperplasia and metaplasia and excessive mucus production. Furthermore, P. aeruginosa virulence factor pyocyanin activated the antagonistic STAT6 and epidermal growth factor receptor signalling pathways to inhibit FOXA2. Unravelling the mechanism of FOXA2 inactivation will hasten the development of non-antibiotic therapeutics to improve mucociliary clearance of pathogens in canine airway.

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In this research, dead leaves of a common ornamental plant, Dracaena draca known also as dragon tree was used as a biosorbent for the removal of Cadmium (Cd(2+)) from aqueous solutions using a full 2(3) factorial experimental design. Three factors were investigated at two different levels, metal ion concentration (X = 10 and 100 ppm), hydrogen ion concentration (Ph = 2 and 7) and biomass dose (BD = 0.1 and 0.5g). Experiments were carried out in duplicates with 50 ml of Cd(2+) solutions at room temperature. When comparing observed values (experimental) with calculated values (model), they were set closely together that allowed suggesting a normal distribution where (R(2) = 0.9938). A characterization of the biosorbent was done by pHzpc and SEM-EDAX. Results also showed that the most significant effect for Cd(2+) biosorption was ascribed to (X). The interaction effects of (pH BD) and (X pH) were found to have significant influence on Cd(2+) removal efficiency. The highest Cd(2+) removal percentage attained by 79.60% at X = 10 ppm, pH = 7 and BD = 0.5g. The reusability of the biosorbent was tested in three desorption cycles and the regeneration efficiency was above 99.7%.