The use of the carbon-13 in the partitioning of photosynthate in vegetative and reproductive twigs of 'Sweet' passion fruit

This study's objective is to evaluate the photosynthates partitioning and source-sink relationships, in vegetative and reproductive twigs of sweet passion fruit, using the carbon-13, stable isotope of carbon. The leaves of vegetative and reproductive twigs were placed in a sealed chamber and 13CO 2 were injected for 30 minutes. After six hours, the different organs of the twig were collected and immersed in liquid nitrogen (-196°C). All plant samples were oven-dried, powdered and combusted in an elemental analyzer. The results showed that the methodology was efficient to evaluate the partitioning of photosynthates. In the vegetative twigs, the new open leaves, the closed leaves and growth meristem were the principal sink for the source leaves enriched with 13CO 2. In the reproductive twigs with only flowers buds, the source-sink relationship was changed and the flowers buds turn to be the principal sink and the growing leaves were secondary sinks. The presence of young fruits changed again the source-sink relationship of the twig, and they were the principal sinks. The apical leaves, with 60% of final leaf area were also a sink for photosynthates.

Leaf spray fertilization of boron and zinc on productivity and fruit quality of Japanese pear tree

The cultivation of fruit plants from temperate climate in tropical or subtropical regions can be a good income alternative for the producer. However, due to the little existent information about cultivation of those fruit plants, the producers use imported techniques of other producing areas, or even an association of practices used for other fruit plants, pointing out the leaf spray fertilization of micronutrients without appropriate scientific base. In this context, the objective of this study was to verify the effect of the leaf spray fertilization of B and Zn on productivity and fruit quality of Japanese pear tree. The experiment was conducted from 2004 to 2005, in Ilha Solteira, in northwestern São Paulo State-Brazil. The climate is, according to the Köpppen Classification, tropical wet and dry (Aw). The 'Okusankichi' cultivar, grafted on Pyrus communis L. rootstock was used as well as doses of 110 g.ha-1 of B and 250 g.ha-1 of Zn in each application. The treatments were: T1. water, T2. boric acid, T3. zinc sulfate, T4. T2 + T3, T5. boric acid + urea + citric acid + EDTA, T6. zinc sulfate + urea + citric acid + EDTA, T7. T5 + T6, T8. boric acid + urea + citric acid + EDTA + sodium molibdate + sulfur + calcium chloride, T9. zinc sulfate + urea + citric acid + EDTA + Fe sulfate + Mn sulfate + Mg sulfate and, T10. T8+T9. A randomized blocks design was used and the averages were compared by Tukey test. In the first crop the mixture of boric acid with quelating agents were efficient to supply B to the plants and zinc sulfate plus quelating agents were efficient to increase Zn leaf content. However, the productivity and the fruit quality were not influenced by the leaf spray of B and Zn. In the second crop the leaf content of B and Zn and the productivity were not influenced by the leaf spray; the boric acid and the zinc sulfate with or without quelating agents increased the contents of total soluble solids and, the boric acid with or without quelating agents increased the contents of total titratable acidity.

Upconversion ultraviolet random lasing in Nd 3+ doped fluoroindate glass powder

An upconversion random laser (RL) operating in the ultraviolet is reported for Nd 3+ doped fluoroindate glass powder pumped at 575 nm. The RL is obtained by the resonant excitation of the Nd 3+ state 2G 7/2 followed by energy transfer among two excited ions such that one ion in the pair decays to a lower energy state and the other is promoted to state 4D 7/2 from where it decays emitting light at 381 nm. The RL threshold of 30 kW/cm 2 was determined by monitoring the photoluminescence intensity as a function of the pump laser intensity. The RL pulses have time duration of 29 ns that is 50 times smaller than the decay time of the upconversion signal when the sample is pumped with intensities below the RL laser threshold. © 2011 Optical Society of America.

Morphological alterations on human radicular dentin after exposure to different fruit juice drinks

Purpose: This in vitro study aimed to evaluate the effect of different fruit juice drinks available in the Brazilian market on smear layer removal and dentinal tubules opening, as well as to verify the effect of toothbrushing subsequently to the juices exposure. Methods: Dentin specimens were prepared and randomly distributed into the control group (distilled water) and twelve types of fruit juice drinks (cashew, orange, mandarin, apple, passion fruit, guava, strawberry, grape, mango, pear, peach, pineapple). The following treatments were applied: immersion or immersion + brushing. After preparation for SEM, photomicrographs were assessed using an index of smear layer removal. Results: No significant differences regarding smear layer removal and dentinal tubules exposure could be observed between the groups after both treatments (Kruskal-Wallis, post-hoc paired comparisons, P>0.05). The control solution and the fruit juice drinks were not able to remove smear layer and to open dentinal tubules. Significant difference between the applied treatments was detected only for the mango juice group (Mann-Whitney, P<0.05). Conclusion: Under the experimental conditions, the different fruit juice drinks did not promote significant alterations on human radicular dentin morphology regardless of the subsequent application of brushing procedures. Copyright: © 2011 Zandim et al.

Efecto del método de secado en las propiedades termodinámicas de pulpa de mora en polvo

Three different types of maltodextrin encapsulated dehydrated blackberry fruit powders were obtained using vibrofluidized bed drying (VF), spray drying (SD), vacuum drying (VD), and freeze drying (FD). Moisture equilibrium data of blackberry pulp powders with 18% maltodextrin were determined at 20, 30, 40, and 50°C using the static gravimetric method for the water activity range of 0.06-0.90. Experimental equilibrium moisture content data versus water activity were fit to the Guggenheim-Anderson-de Boer (GAB) model. Agreement was found between experimental and calculated values. The isosteric heat of sorption of water was determined using the Clausius-Clapeyron equation from the equilibrium data; isosteric heats of sorption were found to increase with increasing temperature and could be adjusted by an exponential relationship. For freeze dried, vibrofluidized, and vacuum dried pulp powder samples, the isosteric heats of sorption were lower (more negative) than those calculated for spray dried samples. The enthalpy-entropy compensation theory was applied to sorption isotherms and plots of ΔH versus ΔS provided the isokinetic temperatures, indicating an enthalpy-controlled sorption process.

Surface study of vitreous carbon obtained from glassy carbon powder

This work presents a surface study of monolithic vitreous (or glassy) carbon - MVC - obtained from vitreous carbon powder. Defective MVC pieces are crushed in a ball mill and size classified by sifting. The MVC powder is mixed with furfuryl-alcohol resin and compacted in a mould using a hydraulic press. Samples with different powder granulometries are produced in this way and carbonized in a furnace under nitrogen atmosphere. Complete carbonization of the powder is achieved in only one day and losses due to breakage of the pieces is less than 5%. These results compare very favorably with respect to traditional MVC production methods where full carbonization may require up to seven days and losses due to breakage can be as high as 70%. After carbonization, samples are sanded and polished. Surface roughness and microstructure are characterized by light microscopy. Porosity is quantified from micrographs using ImageJ software and nanometric height variations are measured by atomic force microscopy. © 2012 Materials Research Society.

Shelf Life of Fresh and Pasteurized Organic Passion Fruit (Passiflora Edulis F. Flavicarpa Deg.) Pulp

The shelf life of the organic passion fruit pulp, both fresh and pasteurized at 70C and 90C and stored under refrigeration, was evaluated. The heat treatment did not affect the sensory and physicochemical characteristics of the pasteurized pulps when compared with the fresh pulp, except for the ascorbic acid content. The pulps were also microbiologically safe. The pulps pasteurized at 70 and 90C were suitable for consumption for a minimum shelf-life period of 207 days of storage under refrigeration and for the fresh pulp it was attributed a shelf-life period of 60 to 90 days. The pulp pasteurized at 70C showed higher acceptance scores for all the attributes and purchase intention scores, suggesting a more stable behavior and higher sensory quality. Practical Applications: This work intended to evaluate the influence of the minimum pasteurization on the sensory acceptance and microbiological and physicochemical characteristics of the organic passion fruit pulp stored under refrigeration, with the aim to identify the shelf life. Heat treatment is one of the processes used for food preservation. Lower pasteurization temperature than that used by the Brazilian industries and storage under refrigeration showed to be appropriate for passion fruit pulp quality. In this way, the microbiological, physicochemical and sensory features of passion fruit were preserved. This work can be used as a reference for passion fruit pasteurization, which is able to increase the shelf life of this fruit while preserving its desirable original features. Journal Compilation © 2012 Wiley Periodicals, Inc.

Development and validation of a successful microbiological agar assay for determination of ceftriaxone sodium in powder for injectable solution

Ceftriaxone sodium is a cephalosporin with broad-spectrum antimicrobial activity and belongs to the third generation of cephalosporins. Regarding the quality control of medicines, a validated microbiological assay for the determination of ceftriaxone sodium in powder for injectable solution has not been reported yet. This paper reports the development and validation of a simple, accurate and reproducible agar diffusion method to quantify ceftriaxone sodium in powder for injectable solution. The assay is based on the inhibitory effect of ceftriaxone sodium on the strain of Bacillus subtilis ATCC 9371 IAL 1027 used as test microorganism. The results were treated statistically by analysis of variance and were found to be linear (r = 0.999) in the selected range of 15.0-60.0 μg/mL, precise with a relative standard deviation (RSD) of repeatability intraday = 1.40%, accurate (100.46%) and robust with a RSD lower than 1.28%. The results demonstrated the validity of the proposed bioassay, which allows reliable ceftriaxone sodium quantitation in pharmaceutical samples and therefore can be used as a useful alternative methodology for the routine quality control of this medicine. © 2012 by the authors; licensee MDPI, Basel, Switzerland.

Physicochemical analysis of Ti-Si-B powder aalloys

Titanium alloys of Ti-Si-B system were manufactured by blended elemental powder method using Ti, Si and B powders as starting materials. It was found that uniaxial and isostatic pressing followed by hot pressing at around 1000°C, for 20 minutes, provided good densification of such alloys. The physicochemical studies were performed by means of scanning electron microscopy, X-ray diffraction, atomic force microscopy and microindentation/wear tests. The investigations revealed a multiphase microstructure formed mainly by α-titanium, Ti6Si2B, Ti5Si3, TiB and Ti3Si phases. The phase transformations after pressureless sintering at 1200°C was also studied by X-ray diffraction for the Ti-18Si-6B composition. As stated in some other researches, these intermetallics in the α-titanium matrix provide high wear resistance and hardness, with the best wear rate of 0.2 mm3/N.m and the highest hardness of around 1300 HV. © (2012) Trans Tech Publications, Switzerland.

Effect of acid fruit juices combined with electric or sonic toothbrushing on root dentin permeability - An in vitro study

The purpose of this in vitro study was to quantify the alterations on human root dentin permeability after exposure to different acid fruit juices and to evaluate the effect of toothbrushing with electric or sonic toothbrush after acid exposure. The root dentin of 50 extracted third molars was exposed with a high speed bur. Crowns were sectioned above the cementoenamel junction and root fragments were used to prepare dentin specimens. Specimens were randomly assigned to 5 groups according to the fruit juice (kiwifruit, starfruit, green apple, pineapple and acerolla). Each specimen was connected to a hydraulic pressure apparatus to measure root dentin permeability using fluid filtration method after the following sequential steps: I) conditioning with 37% phosphoric acid for 30 s, II) root scaling, III) exposure to acid fruit juices for 5 min and IV) electric or sonic toothbrushing without dentifrice for 3 min. Data were analyzed statistically by the Wilcoxon and Mann-Whitney tests at 5% significance level. All fruit juices promoted a significant increase of dentin permeability while toothbrushing decreased it significantly (p<0.05). It may be concluded that all acid fruit juices increased root dentin permeability, while toothbrushing without dentifrice after acid exposure decreased the permeability. The toothbrush mechanism (electric or sonic) had no influence on the decrease of root dentin permeability.

Validation of a stability-indicating RP-LC method for the determination of tigecycline in lyophilized powder

A reversed-phase liquid chromatography (RP-LC) method was validated for the determination of tigecycline in lyophilized powder. The LC method was conducted on a Luna C18 column (250 × 4.6 mm i.d.), maintained at room temperature. The mobile phase consisted of buffer containing sodium phosphate monobasic (0.015M) and oxalic acid (0.015M) (pH 7.0)-acetonitrile (75:25, v/v), run at a flow rate of 1.0 mL/min and using ultraviolet detection at 280 nm. The chromatographic separation was obtained with a retention time of 8.6 min, and was linear in the range of 40-100 μg/mL (r2 = 0.9997). The specificity and stability-indicating capability of the method was proven through forced degradation studies, which also showed no interference of the excipients. The accuracy was 99.01% with a bias lower than 1.81%. The limits of detection and quantitation were 1.67 and 5.05 μg/mL, respectively. Moreover, method validation demonstrated satisfactory results for precision and robustness. The proposed method was applied for the analysis of the lyophilized powder formulation, contributing to improve the quality control and to assure the therapeutic efficacy. © The Author [2012]. Published by Oxford University Press. All rights reserved.

Structure, histochemistry and ultrastructure of the male reproductive accessory glands in the neotropical flat-faced fruit-eating bat Artibeus planirostris (Chiroptera: Phyllostomidae)

Chiroptera, the second largest mammalian order, presents different reproductive strategies and unique reproductive features. However, there are few reports regarding male reproductive accessory glands (RAGs) in Chiroptera. Thus, the aim of the present study was to characterise the RAGs of the exclusively neotropical bat Artibeus planirostris (Chiroptera: Phyllostomidae) macroscopically, microscopically and ultrastructurally. The RAGs were composed of a prostatic complex with two regions (ventral and dorsal) and paraurethral and bulbourethral glands, but no seminal vesicles. The ventral region had an undefined epithelium, with secretory and basal cells, and its secretions were periodic acid-Schiff (PAS) positive. The dorsal region received both deferens ducts, had a columnar pseudostratified epithelium with secretory and basal cells. There were two types of secretions from the dorsal region: one that was basophilic and another that was mixed PAS positive and PAS negative. The paraurethral glands were dispersed in the connective tissue of the urethra, whereas the bulbourethral glands were located in the penile root. Histological and ultrastructural data confirmed the prostatic nature of the ventral and dorsal regions and the holocrine nature of the ventral region, with the latter finding never having been described previously for the prostate gland. Our findings demonstrate the wide discrepancy of RAGs between A. planirostris and other mammals in terms of their composition, structure and morphology. © CSIRO 2013.