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[en] Compaction ratio is highly dependent on the density of the wood materials used in the production of particleboard. Lower density wood materials will produce particleboard with higher compaction ratio and is believed to give better properties. The objective of this study was to evaluate the properties of three layer particleboard made from rubber wood and oil palm trunk with different bulk density as the core layer, while the rubber wood fine particles served as surface layers for both types of particleboard. This study also investigated the effect of shelling ratios on the mechanical and physical properties of the three layer particleboard. Melamine-fortified urea formaldehyde (UF) resin was used as the binder. The modulus of rupture (MOR), internal bond strength (IB) and thickness swelling (TS) of the particle boards were evaluated based on the Japanese Industrial Standard for particleboard (JIS A 5908:2003). The results showed that both species and shelling ratios are variables that influenced the mechanical and physical properties of the particleboard. Despite its lower compaction ratio, particleboard made from rubber wood alone had better strength properties and dimensional stability than particleboard made from a mixture of rubber wood and oil palm trunk. (author)
[en] CASTOR provides a powerful and rich interface for managing files and pools of files backed by tape-storage. The API is modelled very closely on that of a POSIX filesystem, where part of the actual I/O part is handled by the rfio library. While the API is very close to POSIX it is still separated, which unfortunately makes it impossible to use standard tools and scripts straight away. This is particularly inconvenient when applications are written in languages other than C/C++ such as is frequently the case in web-apps. Here up to now the only the recourse was to use command-line utilities and parse their output, which is clearly a kludge. We have implemented a complete POSIX filesystem to access CASTOR using FUSE (Filesystem in Userspace) and have successfully tested and used this on SLC4 and SLC5 (both in 32 and 64 bit). We call it CastorFS. In this paper we will present its architecture and implementation, with emphasis on performance and caching aspects.
[en] Cutleaf coneflower (Rudbeckia laciniata L.), crown-beard (Verbesina occidentalis Walt.), and tall milkweed (Asclepias exaltata L.) are wildflower species native to Great Smoky Mountains National Park (U.S.A.). Natural populations of each species were analyzed for leaf ascorbic acid (AA) and dehydroascorbic acid (DHA) to assess the role of ascorbate in protecting the plants from ozone stress. Tall milkweed contained greater quantities of AA (7-10 μmol g-1 fresh weight) than crown-beard (2-4 μmol g-1 fresh weight) or cutleaf coneflower (0.5-2 μmol g-1 fresh weight). DHA was elevated in crown-beard and cutleaf coneflower relative to tall milkweed suggesting a diminished capacity for converting DHA into AA. Tall milkweed accumulated AA in the leaf apoplast (30-100 nmol g-1 fresh weight) with individuals expressing ozone foliar injury symptoms late in the season having less apoplast AA. In contrast, AA was not present in the leaf apoplast of either crown-beard or cutleaf coneflower. Unidentified antioxidant compounds were present in the leaf apoplast of all three species. Overall, distinct differences in antioxidant metabolism were found in the wildflower species that corresponded with differences in ozone sensitivity. - Wildflower species exhibit differences in ascorbic acid content and redox status that affect ozone sensitivity
[en] The study was aimed at the propagation and molecular characterisation of some introduced clones of Hevea brasiliensis in Ghana. Propagation of H. brasiliensis by stem cuttings and in vitro techniques was used to study alternative procedures for mass production of rubber planting materials. Brown and green stem cuttings of Clone I and Clone II were soaked for 6 hours in 0.0-22.5g/L NAA followed by propagation in a nursery bag filled with nutrient-rich soil. Only the brown stem cuttings of H. brasiliensis survived. The % survival, length of shoots, number of roots as well as length of roots of Clone II was significantly (P<0.05) higher than Clone I. Stem cuttings treated with 15.0g/L NAA significantly (P<0.05) developed higher shoots (83.33%), number of roots (6.167), length of shoots (15.38cm) and length of roots (6.00cm) than the remaining treatments. There was significant (P<0.05) effects of NAA and Clone II in sprouting and rooting growth of the brown stem cuttings. The addition of 5.0mg/L kinetin in the MS culture medium significantly (P<0.05) enhanced higher shoot development (84.00%), number of shoots (3.60) and leaves (23.40) of the shoot-tip explants compared to other treatments. In nodal explants cultured on a medium without kinetin developed higher shoots (94.00%), height of shoot (4.80cm), number of leaves (19.20), number of shoots (6.00) and number of roots (7.00) than those with kinetin treatments. However, 7.5mg/L kinetin of the nodal culture also performed significantly after the controls. A dendrogram derived from the UPGMA distinguished the rubber clones from four areas of Ghana into two clusters. The five SSR markers showed high degree of relatedness among the rubber clones which suggested high genetic similarity (IRCA317-5, IRCA41-2, IRCA331-6, IRCA230-4, IRCA109-3, B8-23) and some degree of diversity/variation (K2-18,IRCA840-7, PB217-8, PB217-10, IRCA317-16) among the clones. Thus, clones of interest could be selected for future breeding and propagation programmes. Successful in vivo and in vitro propagation as well as molecular characterisation (genetic similarity and diversity) of rubber tree (Hevea brasiliensis) in Ghana were achieved. (au)
[en] The corrosion inhibitive property of rubber seed extract obtained by chemical extraction using methanol and diethyl ether was investigated by electrochemical technique. It was found that rubber seed extract obtained by extracting with diethyl ether showed a better inhibition to mild steel corrosion in deionized water as compared to the extract obtained in methanol. A 60% inhibition was achieved when 100 mg/l diethyl ether extracted extract was used at 45 deg. C while methanol extracted extract only gave 35% inhibition
[en] In the framework of WLCG, Tier-1s need to manage large volumes of data ranging in the PB scale. Moreover they need to be able to transfer data, from CERN and with the other centres (both Tier-1s and Tier-2s) with a sustained throughput of the order of hundreds of MB/s over the WAN offering at the same time a fast and reliable access also to the computing farm. In order to cope with these challenging requirements, at INFN Tier-1 we have adopted a storage model based on StoRM/GPFS/TSM for the D1T0 and D1T1 Storage Classes and on CASTOR for the D0T1. In this paper we present the results of the commissioning tests of this system for the ATLAS experiment reproducing the real production case with a full matrix transfer from the Tier-0 and with all the other involved centres. Noticeably also the new approach of direct file access from farm to data is covered showing positive results. GPFS/StoRM has also been sucessfully deployed, configured and commissioned as storage solution for an ATLAS INFN Tier-2, specifically the one of Milano. The results are shown and discussed in this paper together with the ones obtained for the Tier-1.
[en] The goals of this study were to document the development of ozone-induced foliar injury, on a leaf-by-leaf basis, and to develop ozone exposure relationships for leaf cohorts and individual tall milkweeds (Asclepias exaltata L.) in Great Smoky Mountains National Park. Plants were classified as either ozone-sensitive or insensitive based on the amount of foliar injury. Sensitive plants developed injury earlier in the season and to a greater extent than insensitive plants. Older leaf cohorts were more likely to belong to high injury classes by the end of each of the two growing seasons. In addition, leaf loss was more likely for older cohorts (2000) and lower leaf positions (2001) than younger cohorts and upper leaves, respectively. Most leaves abscised without prior ozone-like stippling or chlorosis. Failure to take this into account can result in underestimation of the effects of ozone on these plants. - Leaf loss was not necessarily accompanied by symptoms of foliar ozone injury
[en] Earlier studies on genetic variation and genome analysis of Hevea brasiliensis were based primarily on restriction fragment length polymorphisms (RFLPs). Notwithstanding that the RFLP technique is a powerful tool, the technique is slow, laborious and requires highly polymorphic hybridization probes. The multiplex DAF technique was adopted. Pairs of random 10-mer oligonucleotide primers were tested for their ability to elicit DNA polymorphisms. Preliminary results indicated that the number of amplified products varied with the annealing temperature and the primer pairs. Although it was found that the annealing temperatures had to be varied for different primer pairs in order to achieve satisfactory amplification, all DNA amplification was carried out at a fixed annealing temperature in order to increase the efficiency of screening primer pairs for their ability to reveal comprehensive DNA fingerprints. DNA samples loaded in denaturing buffer and separated through denaturing polyacrylamide gels were found to be more informative than samples loaded in non-denaturing buffer. Staining with silver nitrate was much more sensitive than with ethidium bromide. The DAF marker technique has been developed successfully for Hevea studies. Premilinary investigations with the technique demonstrated that DAF can generate very complex and informative DNA fingerprints and promises to be useful for genetic variability, family relationship and population studies. The technique does not require sophisticated equipment, and is also more robust and reproducible than RAPD. 6 refs
[en] Full text: DPC-9, a popular pistillate line of castor bean (Ricinus communis) is highly susceptible to leafhopper which is tightly linked to a monogenic trait absence or zero bloom (no waxy bloom) on different plant parts. Seeds of DPC-9 were treated with 550Gy r-rays at BARC, Mumbai. Generations of M1 to M10 were raised in winter, at optimal nutrition and irrigation every year and the plants received fundus inoculum. Some plants wilted in M3, due to high inoculum (2 × 103 CFU/g soil) load. Segregation for bloom varying from triple (all parts waxy) to zero bloom was observed in M5 and continuous selection pressure for bloom in pistillate background, led to the selection of 9 DPC-9 mutants with green stem, triple or double bloom, spiny capsules and pistillate expression up to sixth order that of spikes. Among the nine mutant DPC-9 selections, IPC-23, a pistillate line with green stem, triple bloom trait, low node number (7-8), short plant height (40-50cm) to the primary spike, early flowering (30-40 days to 50% flowering) and good branching (10-12) was stabilized. Screening for leafhopper resistance using infester row technique, indicated that IPC-23 is highly resistant to leafhopper (grade 0) compared to checks, DPC-9 and DCH-177 (grade 4). It is also resistant to wilt (8.5%), compared to check, JI-35 (97%) in a wilt infested plot. Genetic similarity coefficient between DPC-9 and IPC-23 was 58% in a genotypic data from 130 SNP loci representing all linkage group of castor beans. Pistillate behaviour is similar to DPC-9, with environmentally sensitive ISF and revertants. IPC-23, a physiologically efficient line with good HI (31.3%) is good combiner for early flowering and maturity. Several hybrids based on IPC-23 yielded 34-134% standard heterosis in preliminary yield trials. (author)