Characterization of the microtube emitters used in a novel micro-sprinkler

The microtube is a simple and cheap emitter that was widely used throughout the world in the early days of drip irrigation. Its length can be adjusted according to the pressure distribution along the lateral line and the discharge from the microtube can be adjusted by its length. This not only counters the pressure loss due to pipe friction but also makes it suitable for undulating and hilly conditions, where pressure in the lateral line varies considerably according to the differences in elevation. This is the major problem facing the designer, i.e., emitter flow changes as the acting pressure head changes. In this study, a novel micro-sprinkler system is proposed that uses microtube as the emitter and where the length of the microtube can be varied in response to pressure changes along the lateral to give uniformity of emitter discharges. The objective of this work is to develop and validate empirical and semi-theoretical equations for the emitter hydraulics. Laboratory testing of two microtube emitters of different diameter over a range of pressures and discharges was used in the development of the equations relating pressure and discharge, and pressure and length for these emitters. The equations proposed will be used in the design of the micro-sprinkler system, to determine the length of microtube required to give the nominal discharge for any given pressure. The semi-theoretical approach underlined the importance of accurate measurements of the microtube diameter and the uncertainty in the estimation of the friction factor for these tubes.

Air trapping: The major factor limiting diaphragm mobility in chronic obstructive pulmonary disease patients

Background and objective: Patients with COPD can have impaired diaphragm mechanics. A new method of assessing the mobility of the diaphragm, using ultrasound, has recently been validated. This study evaluated the relationship between pulmonary function and diaphragm mobility, as well as that between respiratory muscle strength and diaphragm mobility, in COPD patients. Methods: COPD patients with pulmonary hyperinflation (n = 54) and healthy subjects (n = 20) were studied. Patients were tested for pulmonary function, maximal respiratory pressures and diaphragm mobility using ultrasound to measure the craniocaudal displacement of the left branch of the portal vein. Results: COPD patients had less diaphragm mobility than did healthy individuals (36.5 +/- 10.9 mm vs 46.3 +/- 9.5 mm, P = 0.001). In COPD patients, diaphragm mobility correlated strongly with pulmonary function parameters that quantify air trapping (RV: r = -0.60, P < 0.001; RV/TLC: r = -0.76, P < 0.001), moderately with airway obstruction (FEV1: r = 0.55, P < 0.001; airway resistance: r = -0.32, P = 0.02) and weakly with pulmonary hyperinflation (TLC: r = -0.28, P = 0.04). No relationship was observed between diaphragm mobility and respiratory muscle strength (maximal inspiratory pressure: r = -0.11, P = 0.43; maximal expiratory pressure: r = 0.03, P = 0.80). Conclusion: The results of this study suggest that the reduction in diaphragm mobility in COPD patients is mainly due to air trapping and is not influenced by respiratory muscle strength or pulmonary hyperinflation.

Sweet Basil (Ocimum basilicum) Extracts Obtained by Supercritical Fluid Extraction (SFE): Global Yields, Chemical Composition, Antioxidant Activity, and Estimation of the Cost of Manufacturing

In this work, supercritical technology was used to obtain extracts from Ocimum basilicum (sweet basil) with CO(2) and the cosolvent H(2)O at 1, 10, and 20% (w/w). The raw material was obtained from hydroponic cultivation. The extract`s global yield isotherms, chemical compositions, antioxidant activity, and cost of manufacturing were determined. The extraction assays were done for pressures of 10 to 30 MPa at 303 to 323 K. The identification of the compounds present in the extracts was made by GC-MS and ESI-MS. The antioxidant activity of extracts was determined using the coupled reaction of beta-carotene and linolenic acid. At 1% of cosolvent, the largest global yield was obtained at 10 MPa and 303 K (2%, dry basis-d.b.); at 10% of cosolvent the largest global yield was obtained at 10 and 15 MPa (11%, d.b.), and at 20% of cosolvent the largest global yield was detected at 30 MPa and 303 K (24%, d.b.). The main components identified in the extracts were eugenol, germacrene-D, epi-alpha-cadinol, malic acid, tartaric acid, ramnose, caffeic acid, quinic acid, kaempferol, caffeoylquinic acid, and kaempferol 3-O-glucoside. Sweet basil extracts exhibited high antioxidant activity compared to beta-carotene. Three types of SFE extracts from sweet basil were produced, for which the estimated cost of manufacturing (class 5 type) varied from US$ 47.96 to US$ 1,049.58 per kilogram of dry extract.

MODIS NDVI time-series allow the monitoring of Eucalyptus plantation biomass

The use of remote sensing is necessary for monitoring forest carbon stocks at large scales. Optical remote sensing, although not the most suitable technique for the direct estimation of stand biomass, offers the advantage of providing large temporal and spatial datasets. In particular, information on canopy structure is encompassed in stand reflectance time series. This study focused on the example of Eucalyptus forest plantations, which have recently attracted much attention as a result of their high expansion rate in many tropical countries. Stand scale time-series of Normalized Difference Vegetation Index (NDVI) were obtained from MODIS satellite data after a procedure involving un-mixing and interpolation, on about 15,000 ha of plantations in southern Brazil. The comparison of the planting date of the current rotation (and therefore the age of the stands) estimated from these time series with real values provided by the company showed that the root mean square error was 35.5 days. Age alone explained more than 82% of stand wood volume variability and 87% of stand dominant height variability. Age variables were combined with other variables derived from the NDVI time series and simple bioclimatic data by means of linear (Stepwise) or nonlinear (Random Forest) regressions. The nonlinear regressions gave r-square values of 0.90 for volume and 0.92 for dominant height, and an accuracy of about 25 m(3)/ha for volume (15% of the volume average value) and about 1.6 m for dominant height (8% of the height average value). The improvement including NDVI and bioclimatic data comes from the fact that the cumulative NDVI since planting date integrates the interannual variability of leaf area index (LAI), light interception by the foliage and growth due for example to variations of seasonal water stress. The accuracy of biomass and height predictions was strongly improved by using the NDVI integrated over the two first years after planting, which are critical for stand establishment. These results open perspectives for cost-effective monitoring of biomass at large scales in intensively-managed plantation forests. (C) 2011 Elsevier Inc. All rights reserved.

Relating MODIS vegetation index time-series with structure, light absorption and stem production of fast-growing Eucalyptus plantations

By allowing the estimation of forest structural and biophysical characteristics at different temporal and spatial scales, remote sensing may contribute to our understanding and monitoring of planted forests. Here, we studied 9-year time-series of the Normalized Difference Vegetation Index (NDVI) from the Moderate Resolution Imaging Spectroradiometer (MODIS) on a network of 16 stands in fast-growing Eucalyptus plantations in Sao Paulo State, Brazil. We aimed to examine the relationships between NDVI time-series spanning entire rotations and stand structural characteristics (volume, dominant height, mean annual increment) in these simple forest ecosystems. Our second objective was to examine spatial and temporal variations of light use efficiency for wood production, by comparing time-series of Absorbed Photosynthetically Active Radiation (APAR) with inventory data. Relationships were calibrated between the NDVI and the fractions of intercepted diffuse and direct radiation, using hemispherical photographs taken on the studied stands at two seasons. APAR was calculated from the NDVI time-series using these relationships. Stem volume and dominant height were strongly correlated with summed NDVI values between planting date and inventory date. Stand productivity was correlated with mean NDVI values. APAR during the first 2 years of growth was variable between stands and was well correlated with stem wood production (r(2) = 0.78). In contrast, APAR during the following years was less variable and not significantly correlated with stem biomass increments. Production of wood per unit of absorbed light varied with stand age and with site index. In our study, a better site index was accompanied both by increased APAR during the first 2 years of growth and by higher light use efficiency for stem wood production during the whole rotation. Implications for simple process-based modelling are discussed. (C) 2009 Elsevier B.V. All rights reserved.

Determination of heavy metals by inductively coupled plasma-optical emission spectrometry in fish from the Piracicaba River in Southern Brazil

A total of 202 fish, representing 16 species, were collected during 2008 (March-October) in the Tanquan region of the Piracicaba River using nets. Flesh samples were collected and analyzed, using inductively coupled plasma-optical emission spectroscopy for Al, As, Cd, Co Cr, Cu, Mn, Mo, Ni, Ph, Se, Sn, Sr, and Zn. The results showed that the flesh of these fish all contained extremely high levels of Al and Sr, and moderately high levels of Cr, As, Zn, Ni. Mn and Pb. The metals were higher in these fish during rainy season, with fish collected during the months of March and October being the highest. In addition, the accumulation of metals was species-dependent. Cascudos (Hypostomus punctatus) and piranhas (Serrasalmus spilopleura) exhibited high levels of almost all of the metals, while curimbata (Prochilodus lineatus) had moderate levels. A few species, including pacu (Piaractus mesopotamicus) and dourado (Salminus maxillosus), had very low levels of most metals. The results show that the Piracicaba River Basin is widely contaminated with high levels of many toxic heavy metals, and that human consumption of some fish species is a human health concern. (C) 2009 Elsevier B.V. All rights reserved.

Changes in bone mass, biomechanical properties, and microarchitecture of calcium- and iron-deficient rats fed diets supplemented with inulin-type fructans

Feeding mineral-deficient diets enhances absorptive efficiency as an attempt of the body to compensate for the lack of an essential nutrient. Under certain circumstances, it does not succeed, and nutritional deficiency is produced Our hypothesis was that mulin-type fructans (ITF), which arc known to affect mineral absorption, could increase Ca and Fe bioavailability in Ca- and Fe-deficient rats. Male Wistar rats (n = 48, 4 weeks old) were assigned to I of 8 groups derived from 2 x 2 x 2 factorial design with 2 levels of added Fe (0 and 35 mg/kg), Ca (0 and 5 g/kg), and ITF (0 and 100 g/kg) for 33 days. The Fe status (hemoglobin, serum Fe, total Fe-binding capacity, transferrin saturation, liver minerals) was evaluated. Tibia minerals (Ca, Mg, and Zn), bone strength, and histomorphometry were determined In nondeficient rats, ITF supplementation did not affect Fe status or organ minerals, with the exception of tibia Mg Moreover, ITF improved bone resilience and led to a reduction in eroded surface per body surface and number of osteoclasts per area In Ca-deficient rats, ITF increased liver (Fe and Zn) and tibia (Zn) mineral levels but impaired tibia Mg, yield load, and resilience. In conclusion, ITF worsened the tibia Mg levels and elastic properties when supplemented in Ca-deficient diets In contrast, although bone Ca was not affected in nondeficient rats under the present experimental conditions, bone quality improved, as demonstrated by a moderate reduction in femur osteoclast resorption and significant increases in tibia Mg content and elasticity. (C) 2009 Elsevier Inc. All rights reserved.

Physical-chemical and functional properties of maca root starch (Lepidium meyenii Walpers)

The starch of maca (Lepidium meyenii Walpers) presented oval and irregular morphology, with granule size between 7.4 and 14.9 mu m in length and 5.8 and 9.3 mu m in diameter. The isolated starch showed the following features: purity of 87.8%, with 0.28% lipids, 0.2% fibre and 0.12% fixed mineral residue, and no protein detected; the ratio between the amylose and amylopectin contents were 20:80: the solubility at 90 degrees C was 61.4%, the swelling power was 119.0g water/g starch and the water absorption capacity was 45.9 g water/g starch; the gel turbidity rose 44% during the storing time; the gelatinization temperature was 47.7 degrees C and the transition enthalpy 6.22 J/g; the maximum viscosity reached 1260 UB at 46.4 degrees C, with breakdown, setback and consistence of 850, 440 and -410 UB, respectively. The low gelling temperature and the stability during gel refrigeration could be adequate for foods requiring moderate temperature process, but not for frozen food. (C) 2008 Elsevier Ltd. All rights reserved.

Novel sequence types (STs) of Staphylococcus aureus isolates causing clinical and subclinical mastitis in flocks of sheep in the northeast of Brazil

Staphylococcus aureus is one of the most important infectious mastitis causative agents in small ruminants. In order to know the distribution of Staph. aureus strains associated with infectious mastitis in flocks of sheep in the northeast of Brazil and establish whether these clones are related to the strains distributed internationally, this study analysed the genetic diversity of Staph. aureus isolates from cases of clinical and subclinical mastitis in ewes by pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST). In this research, 135 ewes with mastitis from 31 sheep flocks distributed in 15 districts were examined. Staph. aureus was isolated from sheep milk in 9 (29%) out of 31 herds located in 47% of the districts surveyed. MLST analysis allowed the identification of four STs (ST750, ST1728, ST1729 and ST1730). The last three with their respective novel alleles (g/p-220; pta-182 and yqil-180) were recently reported in the Staph. aureus MLST database (http://www.mlst.net). Each novel allele showed only a nucleotide different from those already described. The occurrence of CC133 (ST750 and ST1729) in this study is in agreement with other reports that only a few clones of Staph. aureus seem to be responsible for most cases of mastitis in dairy farms and that some of these clones may have broad geographic distribution. However, the prevalence of CC5 (ST1728 and ST1730)-an important group related to cases of colonization or infection in humans-differs from previous studies by its widespread occurrence and may suggest human contamination followed by selective pressures of the allelic diversifications presented for these STs.

Acute, subacute toxicity and mutagenic effects of anacardic acids from cashew (Anacardium occidentale Linn.) in mice

Aim of the study: Anacardium occidentale Linn. (cashew) is a Brazilian plant that is usually consumed in natura and is used in folk medicine. Anacardic acids (AAs) in the cashew nut shell liquid are biologically active as gastroprotectors, inhibitors of the activity of various deleterious enzymes, antitumor agents and antioxidants. Yet, there are no reports of toxicity testing to guarantee their use in vivo models. Materials and methods: We evaluated AAs biosafety by measuring the acute, subacute and mutagenic effects of AAs administration in BALB/c mice. In acute tests, BALB/c mice received a single oral dose of 2000 mg/kg, whereas animals in subacute tests received 300, 600 and 1000 mg/kg for 30 days. Hematological, biochemical and histological analyses were performed in all animals. Mutagenicity was measured with the acute micronucleus test 24 h after oral administration of 250 mg/kg AAs. Results: Our results showed that the AAs acute minimum lethal dose in BALB/c mice is higher than 2000 mg/kg since this concentration did not produce any symptoms. In subacute tests, females which received the highest doses (600 or 1000 mg/kg) were more susceptible, which was seen by slightly decreased hematocrit and hemoglobin levels coupled with a moderate increase in urea. Anacardic acids did not produce any mutagenic effects. Conclusions: The data indicate that doses less than 300 mg/kg did not produce biochemical and hematological alterations in BALB/c mice. Additional studies must be conducted to investigate the pharmacological potential of this natural substance in order to ensure their safe use in vivo. (C) 2011 Elsevier Ireland Ltd. All rights reserved.

Bioequivalence Evaluation of Single Doses of Two Tramadol Formulations: A Randomized, Open-Label, Two-Period Crossover Study in Healthy Brazilian Volunteers

Background: Tramadol is a well tolerated and effective analgesic used to treat moderate to severe pain. Several generic formulations of tramadol are available in Brazil; however, published information regarding their bioequivalence in the Brazilian population is not available. A study was designed for Brazilian regulatory authorities to allow marketing of a generic formulation. Objective: The purpose of this study was to compare the bioequivalence of 2 commercial tablet preparations containing tramadol 100 mg marketed for use in Brazil. Methods: A randomized, open-label, 2 x 2 crossover study was performed in healthy Brazilian volunteers under fasting conditions with a washout period of 12 days. Two tablet formulations of tramadol 100 mg (test and reference formulations) were administered as a single oral dose, and blood samples were collected over 24 hours. Tramadol plasma concentrations were quantified using a validated HPLC method. A plasma concentration time profile was generated for each volunteer and then mean values were determined, from which C(max), T(max), AUC(0-t), AUC(0-infinity), k(e), and t(1/2) were calculated using a noncompartmental model. Bioequivalence between the products was determined by calculating 90% CIs for the ratios of C(max), AUC(0-t), and AUC(0-infinity) values for the test and reference products using log-transformed data. Tolerability was assessed by monitoring vital signs (temperature, blood pressure, heart rate), laboratory tests (hematology, blood biochemistry, hepatic function, urinalysis), and interviews with the volunteers before medication administration and every 2 hours during the study. Results: Twenty-six healthy volunteers (13 men, 13 women) were enrolled in and completed the study. Mean (SD) age was 30 (6.8) years (range, 21-44 years), mean weight was 64 (8.3) kg (range, 53-79 kg), and mean height was 166 (6.4) cm (range, 155-178 cm). The 90% CIs for the ratios of C(max) (1.01-1.17), AUC(0-t) (1.00-1.13), and AUC(0-infinity) (1.00-1.14) values for the test and reference products fell within the interval of 0.80 to 1.25 proposed by most regulatory agencies, including the Brazilian regulatory body. No clinically important adverse effects were reported; only mild somnolence was reported by 4 volunteers and mild headaches by 5 volunteers, and there was no need to use medication to treat these symptoms. Conclusion: Pharmacokinetic analysis in these healthy Brazilian volunteers suggested that the test and reference formulations of tramadol 100-mg tablets met the regulatory requirements to assume bio-equivalence based on the Brazilian regulatory definition. (Clin Ther 2010;32:758-765) (C) 2010 Excerpta Medica Inc.

Carbohydrates in asymmetric synthesis: enantioselective allylation of aldehydes

An enantioselective metal-mediated addition of allylic bromides to carbonyl compounds was achieved in the presence of the inexpensive and easily accessible carbohydrates saccharose and beta-cyclodextrin. The desired products were obtained in moderate to excellent yields and with up to 93% enantiomeric excess. (C) 2008 Elsevier Ltd. All rights reserved.

Nucleophilic addition of potassium organotrifluoroborates to chiral cyclic N-acyliminium ions: stereoselective synthesis of functionalized N-heterocycles

The stereoselective nucleophilic addition of potassium aryl- and alkynyltrifluoroborates to cyclic N-acyliminium ion derivatives from N-benzyl-3,4,5-triacetoxy-2-pyrrolidinone, affording the respective 5-substituted 2-pyrrolidinone is described. The products were obtained in moderate to good yields and with preference for the syn diastereomer. (C) 2008 Elsevier Ltd. All rights reserved.

Synthesis of unnatural cyclitols via a combined enzymatic-palladium catalysis approach

The Suzuki-Miyaura cross-coupling reaction of a hydroxylated vinyl bromide obtained by a chemoenzymatic approach with a diverse range of potassium organotrifluoroborates has been accomplished catalyzed by Pd(PPh(3))(4) in satisfactory yields. A variety of functional groups are tolerated in the nucleophilic partner. (C) 2008 Elsevier B.V. All rights reserved.

Investigation of charged polymer influence on green fluorescent protein thermal stability

Methods of stabilization and formulation of proteins are important in both biopharmaceutical and biocatalysis industries. Polymers are often used as modifiers of characteristics of biological macromolecules to improve the biochemical activity and stability of proteins or drug bioavailability. Green fluorescent protein (GFP) shows remarkable structural stability and high fluorescence; its stability can be directly related to its fluorescence output, among other characteristics. GFP is stable under increasing temperatures, and its thermal denaturation is highly reproducible. Relative thermal stability was undertaken by incubation of GFP at varying temperatures and GFP fluorescence was used as a reporter for unfolding. At 80 degrees C, DEAE-dextran did not have any effect on GFP fluorescence, indicating that it does not confer stability.