Characterization and properties of blended cement matrices containing activated bamboo leaf wastes

The worldwide production of bamboo generates large volumes of leaf wastes, which are deposited in landfills or burned in an uncontrolled manner, with negative effects in the environment. The ash obtained by calcining of the bamboo leaf waste, shows good qualities as supplementary cementing material for the production of blended cements.The current paper shows a detailed scientific study of a Brazilian bamboo leaf ash (BLA) calcined at 600 °C in small scale condition, by using different techniques (XRF, XRD, SEM/EDX, FT–IR, TG/DTG) and technical study in order to analyse the behaviour of this ash in blended cements elaborated with 10% and 20% by mass of BLA. The results stated that this ash shows a very high pozzolanic activity, with a reaction rate constant K of the order of 10^?1/h and type I CSH gel was the main hydrated phase obtained from pozzolanic reaction. The BLA blended cements (10% and 20%) complied with the physical and mechanical requirements of the existing European standards.     

Changes in lipid composition of germinating barley embryo

Barley seeds,Hordeum vulgare, var. Kenia, were dissected before and after 5 days of germination, to distinguish between the scutellum, the coleoptile half of the embryo and the coleorhiza half of the embryo. Total lipids were extracted from each fraction and analyzed by thin layer chromatography and gas liquid chromatography. In tissues from the coleoptile and coleorhiza halves of the embryo there was a concurrent disappearance of triglycerides with a marked increase of esterified sterols and esterified sterol glucosides. In the scutellum there was also a change in triglycerides, but the variations in contents of esterified sterols and esterified sterol glucosides were much smaller. Mono- and digalactolipids were virtually absent from embryonic tissue. The amounts of linoleic and linolenic acids in esterified sterol glucosides were increased after 5 days of germination in all the embryonic tissues, especially in the coleoptile half. In sterol esters, linoleic acid comprised nearly half of the total fatty acids, and the desaturation after 5 days of germination was much less pronounced.     

Plant fibre reinforced cement components for roofing

Composites of blast furnace slag (BFS) based cement mortar reinforced with vegetable fibres are presented. Roofing components are produced with these composites through a simple and low-energy consuming method, including ordinary vibration and curing in a wet chamber. Composites reinforced with eucalyptus pulp, coir fibres and with a mixture of sisal fibre and eucalyptus pulp gave a suitable performance, with compressive strength higher than 20 MPa and modulus of rupture (MOR) higher than 3 MPa. The performance of tiles made with these composites is in accordance with international requirements, with maximum load higher than 450 N, in wet conditions.     

Fuzzy identification of systems with unsupervised learning

The paper describes a mathematical tool to build a fuzzy model whose membership functions and consequent parameters rely on the estimates of a data set. The proposed method proved to be capable of approximating any real continuous function, also a strongly nonlinear one, on a compact set to arbitrary accuracy. Without resorting to domain experts, the algorithm constructs a model-free, complete function approximation system. Applications to the modeling of several functions among which classical nonlinear ones such as the Rosenbrock and the sine (x, y) functions are reported. The proposed algorithm can find applications in the development of fuzzy logic controllers (FLC).     

Effect of colloidal silica on the mechanical properties of fiber–cement reinforced with cellulosic fibers

The effect of colloidal silica on the hydration reaction of the Portland cement system and its effect on the resulting mechanical properties are not completely understood. Silica nanoparticles can affect the behavior and performance of fiber–cement, such as the calcium–silicate–hydrate gel of the matrix and the fiber–matrix interface bonding. The main objective of this study is to evaluate the effects of various contents of colloidal silica (0, 1.5, 3, 5, and 10 % w/w) on the microstructure and mechanical performance of cement composites reinforced with cellulosic pulp. Fiber–cement composites with unbleached eucalyptus Kraft pulp as the micro-fiber reinforcement were produced by the slurry dewatering technique followed by pressing. The average values of the modulus of rupture of the fiber–cement decreased with increasing colloidal silica content. However, the pullout of the fibers increased significantly in the fiber–cement composites with additions between 3 and 10 % w/w of colloidal silica suspension, as indicated in the scanning electron microscopy images and by the improvement in the energy of fracture values.     

Short-term effects of transcatheter arterial chemoembolisation on metabolic activity of the liver of cirrhotic patients with hepatocellular carcinoma

BACKGROUND: Transcatheter arterial chemoembolisation, a procedure for the treatment of hepatocellular carcinoma, provokes a pronounced but transient increase in hepatic cytolysis parameters. A definite evaluation of the impairment of liver function after this treatment, performed by adequate techniques, is still lacking. AIMS: To assess and quantify the impairment of liver metabolic activity after arterial chemoembolisation in patients with cirrhosis. The variations of hepatic vein pressure gradient provoked by this procedure were evaluated. PATIENTS: 15 patients with cirrhosis (Child's class A and B) and hepatocellular carcinoma. METHODS: 17 transcatheter arterial chemoembolisations with epirubicin, iodised oil, and gelfoam were performed; liver function was assessed before, the following day, and after seven days measuring galactose elimination capacity; aminopyrine breath test was also performed in six patients before the procedure and seven days after. In 10 patients intrinsic hepatic clearance of indocyanine green and hepatic vein pressure gradient were measured by hepatic vein catheterisation before and 30 minutes after chemoembolisation. RESULTS: Intrinsic hepatic clearance of indocyanine green decreased significantly from (mean (SEM)) 355 (140) ml/min to 277 (98) ml/min after the procedure (p = 0.0007). Galactose elimination capacity did not show significant changes, being 4.00 (0.90) mg/min/kg body weight at baseline, 4.20 (0.90) mg/min/kg body weight after one day, and 3.95 (0.87) mg/min/kg body weight seven days after chemoembolisation. Aminopyrine breath test was 2.31 (1.09)% and remained unchanged after treatment, being 2.39 (2.04)% at day 7. Baseline hepatic vein pressure gradient was 17.0 (5.5) mm Hg, and 14.4 (3.7) mm Hg 30 minutes after chemoembolisation (p = 0.09). CONCLUSIONS: A single transcatheter chemoembolisation in cirrhotic patients was detected by galactose elimination capacity and aminopyrine breath test one and seven days after the procedure. Therefore it can be considered a safe therapeutic tool for hepatocellular carcinoma in Child's class A and B cirrhotic patients.     

A neural network approach for identification and fault diagnosis ondynamic systems

The possibilities offered by neural networks for system identification and fault diagnosis problems in dynamic systems are investigated. In particular, an original “neural” procedure is illustrated: its sensitivity and response time enable it to be used in on-line fault diagnosis applications. Some examples are also reported. Even though they pertain to a simple linear dynamic system, these examples highlight the general applicability and advantages of a neural approach     

Sodium citrate as a replacement for sodium chloride in a brine solution when evaluated in cows of different backfat thickness

The objective of this study was to evaluate seven muscles from cow forequarters, which were selected based on backfat thickness; an indicator of supplemental feed before slaughter: Moderate cover (Moderate ? 0.76 cm) and Thin cover (Thin ? 0.51 cm). In addition, enhancement with a brine solution containing either Sodium Chloride or Sodium Citrate was evaluated for differences in shelf-life and meat quality. Moderate carcasses had increased carcass weight, increased fat cover and a lower yield for some of the muscles compared to Thin. However, there were minimal differences for palatability and shelf-life compared to Thin. Trained panelists detected minimal differences between Citrate and Chloride for palatability. Citrate resulted in visually darker steaks, but less discoloration during the display period. Results indicate that while selection of cow carcasses based upon backfat thickness results in minimal quality differences; compared to enhancement with Chloride, Citrate minimally impacts palatability and will extend product shelf-life by reducing discoloration.     

Characterization of striping in fresh, enhanced pork loins

To investigate the striping phenomenon in fresh, enhanced pork, a series of experiments were undertaken to identify possible causes of the problem. No one factor (individual brine components, brine pH, ingredient concentration, enhancement pressure, meat and brine pH, or enhancement level) was specifically identified, which could be used to reduce the severity of the striping problem. Furthermore, tumbling the product for 2h, did not reduce the amount of striping, indicating once striping has occurred, it is permanent. Evaluation of the striping pattern indicates that the stripes are formed not only at the needle injection site, but also follow the muscle fiber orientation. The use of darker pork provided more of a contrast when evaluating striping, thus exacerbating the perceived level of striping.     

Impact of bleaching pine fibre on the fibre/cement interface

The goal of this article was to evaluate the surface characteristics of the pine fibres and its impact on the performance of fibre–cement composites. Lower polar contribution of the surface energy indicates that unbleached fibres have less hydrophilic nature than the bleached fibres. Bleaching the pulp makes the fibres less stronger, more fibrillated and permeable to liquids due to removal the amorphous lignin and its extraction from the fibre surface. Atomic force microscopy reveals these changes occurring on the fibre surface and contributes to understanding the mechanism of adhesion of the resulting fibre to cement interface. Scanning electron microscopy shows that pulp bleaching increased fibre/cement interfacial bonding, whilst unbleached fibres were less susceptible to cement precipitation into the fibre cavities (lumens) in the prepared composites. Consequently, bleached fibre-reinforced composites had lower ductility due to the high interfacial adhesion between the fibre and the cement and elevated rates of fibre mineralization.