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Copyright of Brazilian Journal of Biology is the property of Instituto Internacional de Ecologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Brazilian Journal of Biology is the property of Instituto Internacional de Ecologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Brazilian Journal of Biology is the property of Instituto Internacional de Ecologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The photochemical stability of collagen–chitosan blends in solution and film form was investigated using viscosimetry measurements, UV-Vis spectrophotometry, FTIR spectroscopy and wide angle X-ray diffraction. It was found that the relative viscosity of collagen decreased upon UV irradiation. The initial relative viscosity of collagen–chitosan blends were greater than the viscosity of collagen; upon UV irradiation the viscosity of the blends decreased rapidly. The absorption/scattering of collagen in solution increased during irradiation of the sample as shown by UV-Vis, indicating a conformational transition in the sample. FTIR showed that the amide A, B, I and II bands from collagen are shifted after UV irradiation to lower wave numbers; these shifts in collagen–chitosan blends are less well pronounced. Wide angle X-ray diffraction indicated that collagen and collagen–chitosan blends in film form retain much of their structural characteristics after irradiation.The viscosimetry and UV-Vis spectrophotometry results have shown that solutions of collagen–chitosan blends are less stable photochemically than a pure collagen solution. FTIR spectra have shown, that collagen–chitosan blended films are also less stable photochemically than pure collagen films. Wide angle X-ray diffraction indicates that collagen and collagen–chitosan blend samples in film form are less susceptible to conformational change than equivalent samples in solution. [Copyright &y& Elsevier]

The polymerization of d,l-lactide with organoaluminum initiators bearing two different ligands, acetylacetone (1) and achiral Schiff’s base (2), has been studied. The microstructure of the obtained polymers analyzed by high resolution 13C NMR (125 MHz) is strongly influenced by the nature of the ligand. Al(acac)3 (1) leads to stereocopolymers having random repartition of configurational units while polylactides prepared with aluminum methoxide derivatives bearing as ligand Schiff’s base (2) present some degree of stereoregularity with preferential formation of isotactic sequences.Variation of the ligand linked to the initiator appears as one of the best tools for the moulding of the microstructure of obtained polylactides. [Copyright &y& Elsevier]

Molecular interactions between collagen and chitosan (CC) have the potential to produce biocomposites with novel properties. We have characterised the molecular interactions in CC complexes by viscometry, wide angle X-ray scattering and Fourier transform infrared spectroscopy. It was found that CC are miscible at the molecular level and exhibit interactions between the components; X-ray diffraction of CC blends indicate that the collagen helix structure is lost in CC films with increasing chitosan content. Non-linear viscometic behaviour with decreasing chitosan content is interpreted as evidence of a third structural phase formed as a complex of CC. The blending of collagen with chitosan gives the possibility of producing new bespoke materials for potential biomedical applications. [Copyright &y& Elsevier]

Measuring the performance of public sector organisations has always been a difficult and contentious area. However, with continuing pressures for transparency, accountability and value for money it is one that requires increasing management attention. This paper describes the Balanced Scorecard approach to performance measurement, assesses the applicability of the approach in the public sector and illustrates how the approach was used by Dumfries and Galloway Constabulary in Scotland as part of a strategic policing initiative. [ABSTRACT FROM AUTHOR]

The commercial extractant Acorga CLX-50 and model individual di-2-ethylhexyl pyridine-3,5-dicarboxylate and 2-ethylhexyl pyridine-3-carboxylate in toluene were used for palladium(II) extraction from aqueous HCl solutions. The studies of extraction rate and equilibrium were carried out in systems containing palladium(II) ions in 3.0, 0.1, and 0.1M HCl in the presence of 0.5M sodium chloride and in 0.1M HCl in the presence of 0.1–6.0M lithium chloride and in 0.1M HCl in the presence 0.1–3.5M sodium nitrate. The examined extractants can efficiently extract palladium(II) from aqueous hydrochloric acid and nitrate solutions. The extraction is slow and equilibrium is obtained after 2 hours. The best extraction of palladium(II) is observed from 0.1M HCl solution in the presence of 3.5M sodium nitrate. A spontaneous transfer of palladium(II) to the toluene phase without any phase mixing is also observed. [ABSTRACT FROM AUTHOR]

Calcium salts have been reported to play an important role in the inhibition of postharvest decay of apples and in enhancing the efficacy of postharvest biocontrol agents. Therefore, the present study was conducted in order to examine and compare the effects of calcium and magnesium salts on the germination and metabolism of the postharvest pathogens Botrytis cinerea and Penicitlium expansion, and to determine the effects of these salts on the biocontrol activity of two isolates (182 and 247) of the yeast Candida oleophila. Increasing concentrations of CaCl2 (25–175 mM) resulted in decreased spore germination and germ-tube growth of both pathogens. The greatest effect was observed in the case of B. cinerea. The inhibitory effect could be overcome by the addition of glucose to the germination medium. MgCl2 (25–175mM) had no effect on germination or germ-tube growth of either pathogen, indicating that the calcium cation rather than the chloride anion was responsible for the inhibition. The pectinolytic activity of crude enzyme obtained from the culture medium of both pathogens was also inhibited by 25–175mM CaCl2, with the greatest effect on the crude enzyme from P. expansum. Biocontrol activity of isolate 182 was enhanced by the addition of 90 or 180mM CaCl2, whereas there was no effect on the biocontrol activity of isolate 247. This was apparently due to the inability of isolate 247 to proliferate in apple wounds. It is postulated that enhanced biocontrol activity of isolate 182 of the yeast C. oleophila in the presence of Ca2+ ions is directly due to the inhibitory effects of calcium ions on pathogen spore germination and metabolism, and indirectly due to the ability of isolate 182 to maintain normal metabolism in the presence of ‘toxic’ levels of calcium. [ABSTRACT FROM AUTHOR]

A freeze-fixation technique was used to examine the distribution of ice crystals and the pattern of freezing in peach flower buds. In dormant buds, ice crystals formed at localized sites within the bud axis and scales. Ice crystal formation disrupted tissues and mechanical injury from repetitive freeze-thaw cycles was apparent. There was evidence of ice formation in the floral organs of dormant buds exposed to -25°C but none observed in buds exposed to either -5 or -10 °C. The distribution of ice crystals was different in deacclimated buds. In addition to large ice crystals within the subtending bud axis and scales, evidence of large crystals within the developing floral organs was noted. These crystals were most prominent in the lower portions of the developing flower and peduncle, and caused a separation of the epidermal layer from adjacent cells. The distribution of ice crystals within both dormant and deacclimated peach flower buds corroborated the results of previous thermal analysis experiments. [ABSTRACT FROM AUTHOR]

Exposure of harvested grapefruit to ultraviolet (UV) light induced resistance against the green mould decay caused by Penicillium digitalum. Grapefruit picked at various times during the harvest season responded differently to UV treatments. The UV dose required for development of maximum resistance increased as the season progressed. The initial UV dose required in November-picked fruit for maximum response was 4.8 kJ/m2 It declined to 1.6 and 3.2 J/m2 in December- and January-picked fruit, respectively, and increased to 8 KJ/m2 in February-picked fruit. Correspondingly, the minimum percentage infection developing after UV treatment increased throughout the season from 0 to 35%. Resistance in UV-treated fruit developed to its maximum extent at 24—48 h following exposure to UV light and then decreased. Development of induced resistance in grapefruit peel was affected by the temperature at which the fruit was stored 24 h after UV treatment and before infection with P. digitatum. In the UV-treated fruit, the fungus developed a sporadic mycelium with marked inhibition of sporulation. The activity of phenylalanine ammonia-lyase and peroxidase markedly increased in the peel following exposure of the fruit to UV light. [ABSTRACT FROM AUTHOR]

Objective: To compare the efficacy of cefuroxime axetil and doxycycline in the treatment of patients with Lyme disease associated with erythema migrans.Design: Randomized, multicenter, investigator-blinded clinical trial with clinical evaluations during treatment (8 to 12 days) and at 1 to 5 days and 1, 3, 6, 9, and 12 months post-treatment.Setting: Three university referral centers and one private practice.Patients: A total of 123 patients with physician-documented erythema migrans.Intervention: Patients were treated orally for 20 days with either cefuroxime axetil, 500 mg twice daily (63 patients), or doxycycline, 100 mg three times daily (60 patients).Measurements: Resolution of erythema migrans and of signs and symptoms related to early Lyme disease as well as prevention of late Lyme disease.Results: A satisfactory clinical outcome (success or improvement) was achieved in 51 of 55 (93%) evaluable patients treated with cefuroxime axetil and in 45 of 51 (88%) patients treated with doxycycline (difference, 5%, 95% Cl, -5% to 14%). The only complication at 1 month post-treatment was Lyme arthritis in one patient who received doxycycline. Of the patients with satisfactory outcomes at 1 month post-treatment who were evaluable at 1 year post-treatment, a satisfactory outcome was achieved in 43 of 48 (90%) and in 35 of 38 (92%) patients treated with cefuroxime axetil and doxycycline, respectively (difference, -2%; Cl, -12% to 7%). Lyme arthritis did not develop in any patient after 1 month post-treatment, whereas peripheral neuropathy was suspected in one patient treated with cefuroxime axetil. Thirty percent of patients treated with cefuroxime axetil and 32% of those treated with doxycycline had one or more drug-related adverse events. Doxycycline was associated with more photo-sensitivity reactions (15% compared with 0%; P = 0.001) and cefuroxime axetil with more diarrhea (21% compared with 7%; P = 0.035) and Jarisch-Herxheimer reactions (29% compared with 8%; P = 0.005).Conclusions: Cefuroxime axetil is well tolerated and appears to be equally as effective as doxycycline in the treating of early Lyme disease and in preventing the subsequent development of late Lyme disease. [ABSTRACT FROM AUTHOR]

The permeability and porosity of xylem cell walls are believed to play a major role in defining the ability of a cell or tissue to exhibit deep supercooling. Lanthanum nitrate, was utilized to contrast the permeability of stem tissues in B. lenta, which exhibits deep supercooling, with B. papyrifera, which exhibits equilibrium freezing. Although the two species differed greatiy in their response to low temperature, distribution of lanthanum deposits was quite similar. Primary cell walls of all xylem cell types appeared permeable although lanthanum deposition was patchy. Secondary cell walls of fiber cells were also permeable to lanthanum whereas the secondary wall of vessel elements and xylem parenchyma appeared impermeable to the lanthanum. Pit membranes, in all cell types and the 'protective layer' in xylem parenchyma frequently exhibited deposits of lanthanum. Results of this study indicate that the porosity and permeability of the pit membrane, rather than the entire cell wall may determine the rate of water loss from xylem parenchyma to sites of extracellular ice. If differences exist between the species in the physical structure of these sites, they may explain differences observed in their response to freezing. [ABSTRACT FROM AUTHOR]

Presented is a new method of finite state machine (FSM) implementation targeting LUT-based FPGAs. State encoding is performed simultaneously with decomposition of transition and output functions. This is achieved by applying symbolic functional decomposition. Experimental results show that the presented method significantly reduces the cost of implementations of FSMs for most of the evaluated benchmarks. [ABSTRACT FROM AUTHOR]