Removal of Methylene Blue from an Aqueous Medium Using Atemoya Peel as a Low-cost Adsorbent

Water, Air, & Soil Pollution - The objective of the present study was the synthesis and characterization of chitosan-alginate-based cross-linked copolymer (CACC) for the effective removal of...     

Current Research Projects

In this study, the use of composted hazelnut husk (CHH) as an alternative substrate for a horticultural crop, tomato (cv. Ancon), was evaluated. Before use, the CHH was separated into three different fraction sizes, 0-2 mm, 2-4 m m and 4-6.35 mm. These fractions were then mixed with soil samples, based on increasing ratios (0%, 2%, 4% and 8%, v/v) and different media were prepared. The experiment was arranged in a completely randomized design with three media, four mixture ratios with four replicates under greenhouse conditions. After a growing period of three months, plant growth and some fruit quality properties were measured. Plants were grown more successfully in 0-2 mm and 2-4 mm CHH fraction sizes and 8% mixture ratio. The effect on fruit quality of CHH fractions showed differences, however; 4% and 8% ratios of 0-2 mm CHH fraction size mixed with soil were found to be more effective on fruit quality properties. According to these results, CHH can be used for tomato growing, especially with 4% and 8% ratios of 0-2 mm and 2-4 mm CHH fraction sizes mixed with soil. For tomato plants, research of different combinations of CHH media is recommended to attain better results.     

Selecting areas with rare and restricted fish species in mountain streams of Southern Brazil

1. The delimitation of conservation units may be supported by information on compositional (taxonomic), functional, and phylogenetic diversity of a given locality or region. In this context, systematic conservation planning and key biodiversity areas are promising approaches for biodiversity protection.
2. Factors such as species representativeness and exclusivity may be used to identify geographical distribution patterns and select relevant areas for conservation at a local scale.
3. This study aims to identify areas with rare and restricted fish species in mountain streams in Southern Brazil, using a method that unites ecological and biogeographical approaches.
4. Seven river basins and 152 mountain streams in Southern Brazil were sampled to obtain data on the occurrence and abundance of 115 fish species. The rarity status of each species was determined and endemicity analysis was used to find areas of restricted species (ARS) with three cell sizes.
5. Using larger cells, continuous areas were identified and supported by a higher proportion of rare fish species. Using smaller cells, discontinuous areas were identified within each of the river basins, where rare and endemic fish species occur. Most of the smaller areas relevant for protecting fish fauna were located outside of conservation units.
6. Fundamental areas were selected for the protection of fish species in mountain streams in Southern Brazil. Both the method proposed and the areas with rare and restricted fish species identified may be used to support systematic conservation planning and to delimit new priority areas for conservation.

     

Major discoveries on the dermal skeleton of fossil and Recent polypteriforms: a review

Following the discovery of the first living polypterid, Polypterus bichir, in 1802, almost two centuries later we now know of 15 living species (including four subspecies), 14 belonging to the genus Polypterus and one to the genus Erpetoichthys (Calamoichthys) all inhabiting intertropical Africa. The polypterid fossil record was for a long time reduced to some scarce, disarticulated bones, mainly scales, found in various African deposits covering a wider area than the actual geographical distribution. With the discovery, on one hand, of polypterid scales, vertebrae, dermal bones of the cranium and dorsal spiny rays in South America and, on the other hand, of scales and numerous dorsal spiny rays in Niger and Sudan, and two articulated fossils in Morocco, the story of the polypteriforms has revealed some of its mysteries. The discovery of isopedine between dentine and bony basal plate in the scales of living and fossil polypterid species is considered a synapomorphy of the group, and has been an important aid in discriminating polypterid scales from other ganoid scales. A review of the main findings during the last 20 years is presented.     

A simple test to estimate the salinity resistance of fish with specific application to O. niloticus and S. melanotheron

In order to develop a simple and accurate index of the salinity resistance of tilapia, batches of 10 juveniles (5 to 20 g) of two different species Oreochromis niloticus and Sarotherodon melanotheron reared in freshwater were subjected to gradual increases in salinity until 100% mortality. Seven daily increments of salinity were tested with 4 replicates: 2, 4, 6, 8, 10, 12 and 14 g l⁻¹ day⁻¹, while control batches were kept in fresh water. The temperature was maintained at 27 °C. The concentration of oxygen, ammonia and the pH were not limiting factors. The mortality, monitored on a daily basis, appeared after 2–51 days and was spread out over 1–20 days, depending on the increment of salinity. The higher the daily rate in salinity increase, then the shorter the time lapse before total mortality occurred. The cumulative mortality as a function of salinity fit well with simple linear regressions. The criterion of the resistance to salinity was the index MLS (median lethal salinity) defined at each daily rate as the salinity at which 50% of fish died. For S. melanotheron, the mean MLS was 123.7±3.5 g l⁻¹ whatever the daily rate in salinity. For O. niloticus, the MLS was 46.3±3.4 g l⁻¹ for daily increases in salinity ranging from 2 to 8 g l⁻¹ day⁻¹ and decreased significantly (P<0.05) above this level. The MLS-8 g l⁻¹ day⁻¹ ,which takes into account the full capacity of the fish to adapt to the increasing salinity, appeared to be a simple, optimized and efficient criterion for assessing the resistance to salinity for O. niloticus and S. melanotheron. This criterion can be a useful tool for ranking the different parental strains and hybrids of different genus and species of tilapia used in programmes of genetic selection for growth and salinity tolerance.     

Coffee ripeness monitoring using a UAV-mounted low-cost multispectral camera

Coffee beverage quality is highly correlated with the degree of fruit ripeness. In this sense, monitoring fruit ripeness is of utmost importance for harvest planning and, especially for obtaining high-quality beverages. Currently, this process is carried out through manual counts of unripe fruits, which is laborious and limited to a few plants within the field. This study aimed at evaluating the potential of a low-cost multispectral camera for coffee ripeness monitoring in the Zona da Mata region of Minas Gerais State, Brazil. For that, five fields of Arabica coffee with distinct characteristics were evaluated. During the coffee ripeness period, four flights were carried using a Phantom 4 Pro quadcopter equipped with a Mapir Survey 3W camera for imagery acquisition. After that, nine vegetation indices (VIs) were obtained. For the same dates, the percentage of unripe fruits was obtained using an irregular grid in all fields. The data was split into two ripeness classes: suitable for harvest (R) with?<?30% of unripe fruits; and not suitable for harvest (U), with?>?30% of unripe fruits. Then, a principal component analysis was used to infer the importance of the VIs to discriminate plants with unripe fruits from those with ripe fruits. The first two principal components explained?>?75% of the variance in the datasets from all coffee fields. The VIs were able to discriminate the ripeness classes (U and R) in most fields; however, their performance was directly influenced by the crop yield and canopy volume.

     

Agricultural management practices: Effects on soil properties,root growth and sesame yield

The influence of agricultural management practices, such as organic fertilisation and plant densities on soil properties, root growth, and sesame yield were investigated. Soil samples (depth of 0–20 cm) were taken from a field study with sesame (Sesamum indicum L.) cultivated on a Chromic Luvisol, which was conducted to explore the effects of six fertilisation systems [Non-fertilisation (Control); Mineral fertilisation (Min); Organic fertilisation with 2 (Org-1) and 3 Mg ha^–1 (Org-2) of commercial organic fertiliser Organus B; and with 1 (Tak 1) and 2 Mg ha^–1 (Tak-2) of commercial organic fertiliser Takamix] and two plant densities [111111 (Pdens1) and 55555 (Pdens2) plants ha^–1), in a factorial design (6 × 2) with four blocks. The highest values of soil organic carbon, total nitrogen, root density and sesame yield were found in the Org-2 fertilisation and Pdens1 treatments. We found that organic fertilisation combined with Pdens1 significantly increased root growth. Organic fertilisation treatments were able to maintain 80% of sesame roots distributed at a soil depth of 0–10 cm, whereas the last 20% were distributed at a soil depth of 10.1–20 cm. In conclusion the utilization of commercial organic fertilisers as an organic matter source enhanced soil organic carbon, total nitrogen, and root density that contributed to increase sesame yield. Our findings also suggest that inputs of organic matter source with a correct plant density might change positively soil organic carbon and total nitrogen, root growth, root distribution and sesame yield.     

Semantic segmentation of citrus-orchard using deep neural networks and multispectral UAV-based imagery

Precision Agriculture - Accurately mapping farmlands is important for precision agriculture practices. Unmanned aerial vehicles (UAV) embedded with multispectral cameras are commonly used to map...     

Preliminary results on the chemical composition of the Turkish carob beans

The present study embodies investigations on the chemical composition of three types of carob fruits viz. sisam, fleshy and wild. A perusal of analytical and chromatographic results reveals that the pods of sisam type are rich in sugar content (43.84%) as compared to that of wild and fleshy types. The sugars in general are of non-reducing type. The pods contain four kinds of sugars, namely: glucose, fructose, maltose and sucrose; latter being the principal constituent. In comparison with sugar content the protein content of pods is very low being 2.48%–4.76%. There are four types of amino acids present in the pods, namely: alanine, proline, leucine and valine. The fruits are very poor in fats. As compared to the pods, seeds in general lack sugars but possess higher protein, fat and ash content.

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Zusammenfassung In der Arbeit wurden drei Typen — Sisam, fleischig und wild — der Bohne Ceratonia siliqua untersucht.Wie aus den analytischen und chromatographischen Ergebnissen zu ersehen ist, sind die Früchte des Sisamtyps reicher an Zucker als die wilden und fleischigen Typen. Der maximale Zuckergehalt betrug bei der Sisamart 43,48%. Es wurde festgestellt, daß der Zuckergehalt sich aus Glucose, Fructose, Maltose und Saccharose zusammensetzt, von denen die Saccharose den Hauptbestandteil bildet.Im Vergleich zum Zuckergehalt ist der Proteingehalt sehr niedrig, er schwankt zwischen 2,48 und 4,76%. Vier Aminosäuren konnten nachgewiesen werden, und zwar Alanin, Prolin, Leucin und Valin. Die Früchte sind arm an Ölen. Im Vergleich zu den Fruchtschalen sind die Samen sehr arm an Zuckern, besitzen aber einen höheren Protein-, Fett- und Aschegehalt.

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Résumé Le but de cet étude est d'analyser la nature chimique des fruits de caroubier des types sisam, pulpeux et sauvage. Comme on le constate dans les résultats analytiques et chromatographiques, les fruits de type sisam sont plus riches en protéin que de type pulpeux et la quantité de protéin y atteint à 43.48%. Les sucres sont en général de nature non réduits. Les légumines contiennent 4 types de sucre: glucose, fructose, maltose et saccarose. Entre eux c'est le saccarose qui est le plus abondant. Dans les légumines la quantité de protéin est moins que de la quantité de sucre, on a constaté que cette quantité varie de 2.48% à 4.76%. Les légumines peuvent comporter 4 types d'acide aminé: alanine, proline, leucine et valine. Les fruits sont très pauvres en huile. Les résultats d'analyse des germes ont découvert l'absence de sucre. Pourtant les germes sont riches, d'après ces analyses, en protéin, huile ainsi qu'en cendre.

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Authors are greatly indebted to Tate and Lyle Limited, Research Centre, Kent, England, for the financial support of this project.