Improvement of palm oil through breeding and biotechnology

The oil palm Elaeis guineensis is the highest oil-yielding crop and has the potential to become the major supplier of both edible oil and renewable industrial feedstock. The oil yield from wild groves is presently less than 0.5 t/ha/y. However, through breeding and selection, the oil yield of commercial plantations could reach as much as 8 t/ha/y. New planting materials also have the capability of better oil yields with high iodine value (IV), slow height increment, and larger kernels. The oil also contains considerable amounts of carotenoids (500–700 ppm), vitamin E (600–1000 ppm), and sterols (250–620 ppm). The oil yield of another oil palm species, E. oleifera, is approximately 0.5 t/ha/y with high contents of carotenoids (700–1500 ppm), vitamin E (700–1500 ppm), and sterols (3500–4000 ppm). The above traits could be improved through breeding and biotechnology. Biotechnological efforts at the Palm Oil Institute of Malaysia are directed toward the production of oil with high IV and high monounsaturated fatty acids for edible purposes and industrial uses. Isolation and manipulation of the genes involved in the biosynthesis of fatty acids are the main focus. The aim is to increase the efficiency of conversion of palmitate (C_16:0) to oleate (C_18:1). Levels of palmitate and oleate are controlled by the enzymes acyl-acyl carrier protein (ACP) thioesterase and β-keto acyl ACP synthase II. The chain termination reactions of C_16:0 and C_18:1 are independent, thus paving the way for the possibility of reducing palmitate levels by switching off the palmitoyl ACP thioesterase gene. Paper presented at the 88th AOCS Annual Meeting & Expo. May 11–14, 1997, Seattle, Washington, USA.     

Effect of chitosan and Dysphania ambrosioides on the bone regeneration process: A randomized controlled trial in an animal model

The focus of this triple‐blind study was on evaluating the effect of chitosan combined with Dysphania ambrosioides (A) extract on the bone repair process in vivo. In total, 60 male Wistar rats (Rattus norvegicus albinus) weighing between 260 and 270 g were randomly selected for this study and distributed into four groups (n = 15). Group C (chitosan), Group CA5 (chitosan + 5% of D. ambrosioides), Group CA20 (chitosan + 20% of D. ambrosioides), and Group CO (Control‐Blood clot). In each animal, bone defects measuring 2 mm in diameter were performed in both tibias for placement of the substances. After 7, 15, and 30 days, the animals were sedated and sacrificed using the cervical dislocation technique and the tissues were analyzed under optical microscope relative to the following events: inflammatory infiltrate, necrosis, osteoclasts, osteoblasts, fibroblasts, periosteal, and endosteal bone formation. The data were evaluated to verify distribution using the Kolmogorov–Smirnov test, and variance, using the Levene test; as distribution was not normal, data were subjected to the Kruskal–Wallis and Dunn nonparametric tests (p < .05). A significant inflammatory infiltrate was observed in Group CA5 (p = .008) in the time interval of 7 days, and in Group C at 15 (p = .009) and 30 (p = .017) days. Osteoblastic activity was more significant in Group CA20 (p = .027) compared with CA5 in the time interval of 7 days. Group CA20 demonstrated a significantly higher endosteal and periosteal bone formation value in the time interval of 7 (p = .013), 15 (p = .004), and 30 days (p = .008) compared with the other groups. The null hypothesis was refuted, bone regeneration was faster in spheres with an association of chitosan and 20% extract, and complete bone repair occurred clinically at 15 days and histologically at 30 days. The spheres proved to be a promising method for the biostimulation of alveolar bone repair and bone fractures.     

Patterns of email use by teachers and implications: A Singapore experience

This paper attempts to identify the patterns of email use by schoolteachers. The findings are based on a survey of 2998 Singapore teachers whose teaching experiences ranged from 24 to 48 months. The result shows that teachers use email mainly to communicate with colleagues, and the degree of email use varies according to the school level that the teachers are working in. While the teachers teaching at higher school levels (Grades 11–12) email their colleagues more frequently than their counterparts teaching at lower school levels especially primary school teachers, the latter tend to email parents more frequently than other teachers. Implications of the findings are discussed in relevance to pre-service teacher education, teacher professional development and ICT adoption in organisations.     

Fundamental Analysis of Profitability of Large Engineering and Construction Firms

This research examines the strategic performance of sixty-one large international engineering and construction (E&C) firms from the regions of North America, Europe, and East Asia. The primary objective is to identify critical factors of corporate strategy that potentially affect the prospects of a large E&C firm. The research methodology relies on financial analysis and strategic management theories to draw meaningful conclusions. Statistical tests are selectively conducted to assess various aspects, including profitability, capital structure and asset liquidity. This paper documents the research findings for the first aspect—profitability. The first part of the findings suggests that there is no significant correlation between firm size and profitability. Large firms, which are endowed with greater resources and prowess, are not guaranteed to be more profitable. However, firm size has some influence on generic strategies, as large firms tend to adopt either a broadly targeted or a nonrelated diversification strategy. Regional trends of revenue growth of firms are subsequently presented. Despite strong forces of globalization experienced in many other industries, the growth trends suggest that the construction business remains largely localized in nature. Consequently, domestic and regional economic outlook, rather than global trends, should be given more weights in strategic planning.     

Robustness of time‐scale learning of robot motions to uncertainty in acquired knowledge

A disadvantage of present iterative learning control algorithms is that they are generally applicable only in cases where a certain task is performed over and over again. Consequently, if knowledge or control inputs acquired from learning a task can be used on similar tasks, learning will be more efficient. Recently, several methods for constructing the control input of a new motion based on the control inputs acquired from previous learning of similar tasks have been proposed. However, these methods assumed that the perfect control inputs could be obtained from the previous learning. In practice, the control inputs could never be obtained exactly from learning in the presence of certain uncertainties such as disturbance and measurement noises. In addition, it is also not known for sure how the basic motion patterns should be chosen for learning. In this article, the robustness problem of the time‐scale learning control to uncertainty in the acquired learning control inputs is formulated and solved. From the analysis, certain new insights such as its implication to choices of basic motion patterns for time‐scale learning will be discussed. Simulation results of a 3‐link robot are presented to illustrate the analysis. © 2001 John Wiley & Sons, Inc.     

High yield luminescence of a novel europium complex by excimer excitation and f–f absorption of Eu

A new organic ligand, 2-allyl-1,3-diphenyl-1,3-propanedione (ADP), and the corresponding quaternary Eu³⁺ complex, bi (ADP) (dibenzoyl methane) (1,10-phenanthroline) europium(III) [Eu(ADP)₂(DBM)(Phen)] have been synthesized. Excellent red luminescence from the Eu³⁺ complex was observed excited at 419 nm, and the broad visible excitation band is attributed to excimer absorption. The luminescence quantum yield excited at 419 nm (34 ± 3%) was higher than that at 380 nm (30 ± 3%). This is the first time to find strong and high yield excimer excitation absorption for a europium complex at room temperature, therefore, the excimer absorption band located in visible region (400–500 nm). Moreover, very high yields of direct f–f excitation absorption of Eu³⁺ ions at 466 nm (104 ± 10%) and 536 nm (96 ± 10%) were firstly observed, and the excitation spectrum for the europium complex in solid state is extended in wide region from 220 nm to 580 nm.     

Numerical and experimental investigation of preform design in non-axisymmetric warm forming

This paper describes a numerical and experimental investigation of preform design in non-axisymmetric warm forming in order to achieve a large reduction in the volume of flash. A titanium TA2 watch-case-like component was used as an example. Sixteen different shapes of hollow preforms were specially designed for finite-element simulation. Their diameters of the center-holes were designed based on the values of the diameters of end-face configurations of punches and ejectors. The corresponding thicknesses of the preforms were determined by the assumption of constant volume. Under the same processing conditions, the diameter of center-hole of the preform should be the inner diameter of ejector such that its volume of flash was able to be greatly reduced to 6% of the volume of the formed component whereas the volume of flash was approximately 25% in the conventional implementation. Experiments were subsequently performed to verify the simulation results. This study rationally demonstrates the success of the preform design for warm forming of non-axisymmetric components, and provides great improvement in the utilization of material in the bulk forming process. Thus, the achievement is a tremendous saving in materials, more than a fourfold, particularly for these rare and expensive alloys.     

Degradation kinetics of epoxidized soybean oil composites filled with sisal fiber

Epoxidized soybean oil (ESO) composites were cured with methyl tetrahydrophthalic anhydride (MTHPA) and 2,4,6-tris(dimethylaminomethyl)phenol (DEH 35) as a catalyst, sisal fibers were added at 10% and 30% of percent per weight. Composites curing was monitored using Fourier transform infrared spectroscopy, whereas the thermal stability and the degradation kinetics were investigated using thermogravimetry (TG). ESO/MTHPA/DEH35/S10 and ESO/MTHPA/DEH35/S30 composites displayed curing temperatures approximately 100°C lower related to ESO/MTHPA/DEH35, as well as higher degree of conversion. Sisal addition improved the thermal stability, shifting the weight loss shifting the weight loss onset to higher temperature (from 82 to 120°C). Thermal degradation energy $$ was determined using Friedman, Kissinger-Akahira-Sunose and Ozawa-Flynn-Wall models. Sisal significantly increased $$, especially in the intermediate phase (α = 0.2 and 0.8). The degradation kinetics was investigated by TG, and the degradation mechanisms modeled using Kamal-Sourour, Sestack-Berggren, and 1st order (F1), showed excellent fit, with R² > 0.99. Acquired results demonstrate that sisal fiber addition benefited the curing process and increased the thermal stability of ESO composites.     

Activity of a melimine derived peptide Mel4 against Stenotrophomonas,Delftia, Elizabethkingia,Burkholderia and biocompatibility as a contact lens coating

Purpose

To determine the antimicrobial activity of the melimine derived peptide Mel4 against Delftia, Stenotrophomonas, Elizabethkingia, Burkholderia and to investigate biocompatibility of Mel4 as an antimicrobial coating on contact lenses in animals and humans.