Carbon isotope composition and leaf anatomy as a tool to characterize the photosynthetic mechanism of Artemisia annua L.

Leaves of Artemisia annua L. are a plentiful source of artemisinin, a drug with proven effectiveness against malaria. The aim of this study was to classify the photosynthetic mechanism of A. annua through studies of the carbon isotope composition (δ 13C) and the leaf anatomy. A. annua presented a δ 13C value of - 31.76 ± 0.07, which characterizes the plants as a typical species of the C3 photosynthethic mechanism, considering that the average δ 13C values for C3 and C4 species are -28 and -14, respectively. The leaf anatomy studies were consistent with the δ 13C results, where, in spite of the existence of parenchymatic cells forming a sheath surrounding the vascular tissue, the cells do not contain chloroplasts or starch. This characteristic is clearly different from that of the Kranz anatomy found in C4 species.

Diurnal variation of zooplankton biochemical composition and biomass in plankton production tanks

The nutritional value of zooplankton (lipid and phosphorus contents) was analyzed in outdoor, plankton-culture tanks, to monitor the effects of diurnal variation and fertilization. Total lipid contents were significantly higher (average values of about 14% DW) for the treatment fertilized during the sampling week. A significantly highher total lipid concentrations generally coincided with high biomass of Moina sp. (Cladocera) and Thermocyclops sp. nauplii (Copepoda), which is probably related to zooplankton filtration rates. The values tended to be higher during the afternoon and the night. Phosphorus contents in the zooplanktonic population varied from 0.15 to 0.91% DW, with significant differences among the tanks. The zooplankton nutritional quality was greatly influenced by fertilization, which also determined the species composition in the tanks.

Effects of Plasma Immersion Ion Implantation (PIII) of nitrogen on hardness, composition and corrosion resistance of Ti-6Al-4V alloy

Ti-6Al-4V samples have been treated by PHI processing at different temperatures (400-800°C), treatment time (30-150 min) and plasma potential (100 and 420 V). Hardness measurements results showed an enhancement of the hardness for all implanted samples. XRD results detected the Ti 2N phase and the best corrosion resistance was found for the samples processed at higher temperature and lower PIII time.

Tree species composition and environmental relationships in a Neotropical swamp forest in Southeastern Brazil

We examined the relationships between topography, soil properties and tree species composition in a Neotropical swamp forest in southeastern Brazil. Plots were sampled in the forest, encompassing three different soil ground water regimes along the topographical declivity. All non-climbing plant individuals with trunk height >1.3 m were sampled. A canonical correspondence analysis-CCA-of the species-environmental relationships grouped tree species according to drainage and chemical soil conditions. A total of 86 species were found, being 77 species in the inferior, 40 species in the intermediate and 35 species in the superior topographic section. Some species were among the 10 most abundant ones, both in the overall sampled area and in each topographical section, with alternation events occurring only with their abundance position. However, substantial differences in floristic composition between sections were detected in a fine spatial scale, due to higher number of species, diversity index (H′) and species unique (exclusives) in the inferior topographic section. These higher values can be attributed to its higher spatial heterogeneity that included better drained and seasonally waterlogged soils, higher soil fertility and lower acidity. The increase of the soil water saturation and the uniform conditions derived from the superficial water layer has led to a lower number of species and an increase on the palm trees abundance in the intermediate and superior sections. Our results showed that at a small spatial scale niche differentiation must be an important factor related to the increase of the local diversity. The wide distribution of the most abundant species in the studied area and the increase of local diversity corroborate the pattern of distribution of species in larger scales of swamp forests, in which the most abundant species repeat themselves in high densities in different remnants. However, the floristic composition of each remnant is strongly variable, contributing to the increase of regional diversity. © 2008 Springer Science+Business Media B.V.

Tissue composition and muscularity of lamb legs fed with sunflower seeds and vitamin E

The purpose of this study was to evaluate the tissue composition and carcass muscularity of 32 legs of Ile de France lambs fed with diets containing sunflower seeds and vitamin E, with mean body weight of 15 kg, lodged in individual pens at 15 kg and slaughtered at 32 kg of body weight. The treatments influenced (P<0,05) leg weight, femur length and muscle: bone ratio, being the highest values (2,13 kg, 16,19 cm and 7,38, respectively) in lambs that received diet without sunflower seeds and vitamin E. The other variables were not affected (P>0,05) by the treatments. The interaction of the sunflower and vitamin E was positive for bone total weights and intramuscular fat.

Silver colloidal nanoparticles: Effect on matrix composition and structure of Candida albicans and Candida glabrata biofilms

Aim: The aim of this study was to assess the effect of different silver nanoparticles (SN) concentrations on the matrix composition and structure of Candida albicans and Candida glabrata biofilms. Methods and Results: Candida biofilms were developed in 6-well microtiter plates during 48 h. After, these biofilms were exposed to 13·5 or 54 μg SN ml-1 for 24 h. Then, extracellular matrices were extracted from biofilms and analysed chemically in terms of proteins, carbohydrates and DNA. To investigate the biofilm structure, scanning electron microscopy (SEM) and epifluorescence microscopy were used. SN interfered with the matrix composition of Candida biofilms tested in terms of protein, carbohydrate and DNA, except for the protein content of C. albicans biofilm. By SEM, Candida biofilms treated with SN revealed structural differences, when compared with the control groups. Further, SN showed a trend of agglomeration within the biofilms. Epifluorescence microscopy images suggest that SN induced damage on cell walls of the Candida isolates tested. Conclusions: In general, irrespective of concentration, SN affected the matrix composition and structure of Candida biofilms and these findings may be related to the mechanisms of biocide action of SN. Significance and Impact of the Study: This study reveals new insights about the behaviour of SN when in contact with Candida biofilms. SN may contribute to the development of therapies to prevent or control Candida infections. © 2012 The Society for Applied Microbiology.

Chemical composition and antioxidant activity of dried powder formulations of Agaricus blazei and Lentinus edodes

Several mushroom species have been pointed out as sources of antioxidant compounds, in addition to their important nutritional value. Agaricus blazei and Lentinus edodes are among the most studied species all over the world, but those studies focused on their fruiting bodies instead of other presentations, such as powdered preparations, used as supplements. In the present work the chemical composition (nutrients and bioactive compounds) and antioxidant activity (free radical scavenging activity, reducing power and lipid peroxidation inhibition) of dried powder formulations of the mentioned mushroom species (APF and LPF, respectively) were evaluated. Powder formulations of both species revealed the presence of essential nutrients, such as proteins, carbohydrates and unsaturated fatty acids. Furthermore, they present a low fat content (<2 g/100 g) and can be used in low-calorie diets, just like the mushrooms fruiting bodies. APF showed higher antioxidant activity and higher content of tocopherols and phenolic compounds (124 and 770 μg/100 g, respectively) than LPF (32 and 690 μg/100 g). Both formulations could be used as antioxidant sources to prevent diseases related to oxidative stress. © 2012 Elsevier Ltd. All rights reserved.

Composition and interrelationships of a large Neotropical freshwater fish group, the subfamily Cheirodontinae (Characiformes: Characidae): A case study based on mitochondrial and nuclear DNA sequences

•Relationships of Cheirodontinae based on a broad taxonomic sample.•Results reject the monophyly of Cheirodontinae as previously conceived.•Exclusion of Amazonspinther and Spintherobolus from the subfamily Cheirodontinae.•The removal of Leptagoniates pi of the genus Leptagoniates and inclusion in Cheirodontinae.•Division of Cheirodontinae in three newly defined monophyletic tribes. Characidae is the most species-rich family of freshwater fishes in the order Characiformes, with more than 1000 valid species that correspond to approximately 55% of the order. Few hypotheses about the composition and internal relationships within this family are available and most fail to reach an agreement. Among Characidae, Cheirodontinae is an emblematic group that includes 18 genera (1 fossil) and approximately 60 described species distributed throughout the Neotropical region. The taxonomic and systematic history of Cheirodontinae is complex, and only two hypotheses about the internal relationships in this subfamily have been reported to date. In the present study, we test the composition and relationships of fishes assigned to Cheirodontinae based on a broad taxonomic sample that also includes some characid incertae sedis taxa that were previously considered to be part of Cheirodontinae. We present phylogenetic analyses of a large molecular dataset of mitochondrial and nuclear DNA sequences. Our results reject the monophyly of Cheirodontinae as previously conceived, as well as the tribes Cheirodontini and Compsurini, and the genera Cheirodon, Compsura, Leptagoniates, Macropsobrycon, Odontostilbe, and Serrapinnus. On the basis of these results we propose: (1) the exclusion of Amazonspinther and Spintherobolus from the subfamily Cheirodontinae since they are the sister-group of all remaining Characidae; (2) the removal of Macropsobrycon xinguensis of the genus Macropsobrycon; (3) the removal of Leptagoniates pi of the genus Leptagoniates; (4) the inclusion of Leptagoniates pi in the subfamily Cheirodontinae; (5) the removal of Cheirodon stenodon of the genus Cheirodon and its inclusion in the subfamily Cheirodontinae under a new genus name; (6) the need to revise the polyphyletic genera Compsura, Odontostilbe, and Serrapinnus; and (7) the division of Cheirodontinae in three newly defined monophyletic tribes: Cheirodontini, Compsurini, and Pseudocheirodontini. Our results suggest that our knowledge about the largest Neotropical fish family, Characidae, still is incipient. © 2013 Elsevier Inc..

Preliminary assessment of the quantitative relationships between testicular tissue composition and ultrasonographic image attributes in the ram

This study examined the relationships between gross chemical composition and ultrasonographic characteristics of the ram testes. Ten testes from sexually mature Karakul rams were scanned ex situ with an 8-MHz linear-array transducer, in a transverse and longitudinal plane. All ultrasonograms were saved as digital images and subjected to computerized analyses. Crude protein content was determined by the Kjeldahl method, moisture was determined with an oven-drying method, and fat was measured by the Soxhlet extraction of dried samples. Mean pixel values (r = -0.64, P = 0.04), pixel heterogeneity (standard deviation of pixel values; r = -0.64, P = 0.04) and maximum pixel intensity (r = -0.76, P = 0.01) were all negatively correlated with parenchymal protein content. Pixel heterogeneity correlated directly with extractable lipids (r = 0.66, P = 0.02). The quantitative correlations between echotextural and biochemical parameters found in the present experiment confirm the utility of ultrasonographic imaging combined with computer-assisted image analysis for determining changes in testicular histophysiology. © 2013 Elsevier Ltd. All rights reserved.

Composition and quantification of the anthropogenic and natural fractions of wastes collected from the stormwater drainage system for discussions about the waste management and people behavior

A study was made of the composition of wastes collected from the pipes of the stormwater drainage system of Sorocaba, SP, Brazil (600 thousand inhabitants). A total of 10 samples weighing at least 100 kg each were sorted into 19 items to determine the fraction that can be considered natural (earth/sand, stones, organic matter, and water, the latter determined after oven-drying the samples) and the anthropogenic fraction (the remaining 15 items, especially construction and demolition wastes and packaging). Soil/sand was found to be the main item collected (52.5 % dry weight), followed by the water soaked into the waste (24.3 %), which meant that all the other wastes were saturated in mud, whose contents varied from 6.4 % (glass) to 87.2 % (metalized plastics packaging). In general, 83 % of the collected wastes can be classified as natural, but the remaining 17 % represent 2,000 kg of the most varied types of wastes discarded improperly every day on the streets of the city. This is an alarming amount of wastes that may clog parts of the drainage systems, causing troubles for all the population (like flooding) and must be strongly considered in municipal solid wastes management and in environmental education programs. © 2013 Springer Science+Business Media Dordrecht.

Species composition and abundance of the benthic community of Axiidea

ABSTRACT: The thalassinideans (Axiidea and Gebiidea) encompasses approximately 615 species with reclusive habits, generally confined to extensive galleries burrowed into the sand or mud and, more rarely, in openings in reefs or the cavities of sessile animals such as sponges and coral. These species use the galleries for shelter, feeding and breeding, except during the pelagic larval stage. They inhabit estuaries, bays, lagoons, beaches, seas and both tropical and temperate oceanic areas throughout the world, distributed predominantly in the intertidal zone (mid-littoral and infralittoral zones). The aim of the present study was to assess the species composition and abundance of thalassinideans, comparing two micro-habitats (consolidated and non-consolidated substrates), and determine whether there is a correlation between abundance of the organisms and time of the year, collection sites or salinity. Twelve monthly samplings were carried out between August 2006 and July 2007 over consolidated and non-consolidated bottoms of the upper and lower portions of the mid-littoral zones, with three sub-samplings, totaling 48 monthly samples and 576 in all. A total of 651 individuals were collected – 114 Lepidophthalmus siriboia Felder & Rodrigues, 1993 and 537 Upogebia vasquezi Ngoc-Ho, 1989. There was correlation between the abundance of both species and salinity, but U. vasquezi was more abundant in the rainy season. Lepidophthalmus siriboia appears to prefer non-consolidated substrates, whereas U. vasquezi prefers consolidated substrates. The recruitment period for the callianassid L. siriboia appears to occur in just two periods of the year and is more intense in the dry season, whereas U. vasquezi is more frequent throughout the year. The smallest and largest sizes (carapace length – CL) recorded for L. siriboia were smaller than those recorded for the species in northeastern region of Brazil. CL values for ovigerous females suggest that U. vasquezi reaches sexual maturity at a smaller size than L. siriboia.

Effect of coastline properties and wastewater on plankton composition and distribution in a stressed environment on the north coast of Olinda-PE (Brazil)

Foi realizado um estudo sobre a estrutura das comunidades planctônicas ao longo das praias de Casa Caiada e Rio Doce (Pernanbuco, Brasil). A área de estudo sofre grande influência antrópica onde as condições ambientais são controladas pela presença de estruturas costeiras, reduzindo a intensidade da circulação neste ambiente; e pelos efluentes clandestinos de esgoto que aportam águas poluídas para dentro do sistema protegido. Os resultados obtidos indicam que nas zonas protegidas as águas apresentam alta turbidez, temperaturas elevadas, salinidades reduzidas e altas concentrações de nutrientes e oxigênio. Estas condições são responsáveis pela redução da diversidade do plâncton e pelo aumento da biomassa das espécies mais resistentes. As diferenças registradas com respeito a áreas similares, porém não impactadas, parecem indicar que a estrutura planctônica pode ser usada como um indicador da qualidade ambiental, sugerindo uma baixa qualidade das praias em estudo.