Applying boron to coconut palm plants: effects on the soil, on the plant nutritional status and on productivity boron to coconut palm trees

Boron, one of the micronutrients frequently found in low levels in tropical soils affects nutrition and productivity of coconut palm trees essentially cultivated in tropical climates. The objective of this research study was to evaluate the effect of boron on the nutritional status of the plant and its productivity when artificially applied to the culture soil. The experiment was carried out in a four year old, artificially irrigated, dwarf coconut palm orchard in Brazil, between January, 2005 and October, 2006. The soil was a red yellow Latosol (B: 0.18 mg dm(-3)). The treatments consisted in the application of five boron dosages: zero, 1, 2, 4, and 6 kg ha(-1). In the field, the treatments were arranged according to a completely randomized block design, with four replications. Boron (borax) dosages were applied in equal halves directly into the soil in the months of January and February of 2005. Boron concentration in the soil and plant and plant productivity were evaluated. The higher palm tree production was associated to levels of 0.6mg dm(-3) of B in the soil and 23.5mg kg(-1) in leaves. Ninety five percent of palm trees maximum production was obtained with the use of a boron dosage of 2,1kg ha(-1).

Fibras naturais: características químicas e potenciais aplicações

This study has as objective determining the chemical properties that serve as the basis for potential scientific and technological applications of seven species of fibrous plants cultivated in Brazil, which are: Banana” (Musa spp.), “Coco” (Cocos nucifera), Curauá (Ananas erectifolius), Fique (Furcraea andina), Piteira” (Furcraea gigantea), Sisal(Agave sisalana) and “Taboa” (Typha domingensis). The tests for determining the percent dry completely, extractives soluble in cold water, in hot water, in sodium hydroxide 1% and in ethanol-toluene, and the percentages of ash, hydrophobicity, lignin, holocellulose and cellulose were performed at the Department of Environmental Sciences, Agronomy College (FCA) of UNESP – Botucatu, São Paulo State. It also presents a literature review about these fibers and their potential applications. Differences between the results obtained and those found by other authors are possibly explained by variations on the origin of plant material, the harvest season, the climate and soil where they were grown. However, the results and the methodology used, serve as a basis for further studies with natural fibers

Estudo dos fatores de virulência e resistência à oxacilina em Staphylococcus spp. isolados de aspirado traqueal de pacientes em ventilação mecânica internados em UTI

Patients that are mechanically ventilated in ICUs are constantly exposed to different pathogens, which present multiantibiotic resistance. Among these microorganisms, is MRSA (Meticillin-Resistant Staphylococcus aureus) considered to be a therapeutic challenge due to its resistance to β-lactam antibiotics. Therefore, this study proposed to identify species of Staphylococcus spp. isolated from mechanically ventilated patients in ICU, the gene mecA detection and the genes of the enterotoxins A (sea), B (seb), C (sec-1) and D (sed) in samples of S. aureus, as well as the phenotypic resistance determination to oxacillin using the disc-diffusion method with discs of oxacillin and cefoxitin. The samples collection occurred during in a period of 19 months, obtaining samples from 232 patients. A percentage of 39% (70) of Gram-positive cocci were found; which 82,8% (58) were identified as Staphylococcus spp,. among these, 75,8% (44) corresponded to S. aureus species and 47,7% were identified as MRSA. It was found resistance to both drugs in 31,8% of the S. aureus samples, 16 (36,3%) had the gene sea and 11 (25%) had the sec-1 gene. Among the coagulase-negative staphylococci obtained, the species most found was S. epidermidis, corresponding to 43% (6). The results revealed that one of the most important etiologic agents of VAP amid the Gram-positive cocci is the species S. aureus, with special attention to MRSA. The presence of enterotoxins genes in S. aureus did not showed determinant role in VAP, but the presence of these superantigens can contribute worsening the patient’s prognosis, since they are associated with intense inflammatory response

Condições de saúde bucal de crianças e adolescentes portadores de síndrome de Down

Patients with Down syndrome have shown different conditions of oral health, and there is a low occurrence of dental caries and a higher susceptibility to periodontal diseases. Thus, this study aimed to evaluate the prevalence of dental caries and periodontal diseases in subjects with Down syndrome. The population was composed of 40 patients with the syndrome, aged 6 to 18 years, of both genders, and an equal number of non-syndromic patients. The periodontal conditions were evaluated by mean of the criteria of PSR and dental conditions were registered following indexes dmft and DMFT. It was found that in children with Down syndrome, the dmft index was 1.17 and DMFT 3.53 while the control group was verified dmft 1.97 and DMFT 2.77. The results of PSR evidenced that 32.5% of children with Down syndrome were periodontally healthy, 65% were gingivitis patients and 2.5% were periodontitis patients, while in the control group, 50% healthy and 50% were gingivitis patients. The results evidenced similar populations of cariogenic cocci between patients with Down syndrome and non-syndromic subjects. It was concluded that the incidence of caries in children with Down syndrome was higher in permanent teeth compared with the control group, while in the occurrence of deciduous teeth caries was slightly higher in the control group, so when children with Down syndrome are subjected to periodic examinations, they present themselves periodontally healthy.

Condições bucais de crianças e adolescentes portadores de síndrome de down

Os pacientes com síndrome de Down têm mostrado diferentes condições de saúde bucal, destacando-se uma baixa ocorrência de cárie e maior suscetibilidade às doenças periodontais. Assim, o presente estudo objetivou avaliar a prevalência de cárie, patologias periodontais e níveis de cocos cariogênicos em portadores de Síndrome de Down. A população foi constituída de 40 pacientes portadores da síndrome, com idade de 6 a 18 anos, de ambos os gêneros, e igual número de pacientes do grupo controle, os quais foram submetidos ao exame clínico periodontal segundo os critérios do PSR e para determinação do índice de cárie empregando-se os índices ceo-d e CPOD, e avaliação dos níveis de cocos cariogênicos através do real-time PCR. Verificou-se que nas crianças com síndrome de Down o índice médio ceo-d foi 1,17 e o CPO-D 3,53 enquanto que no grupo controle foi observado ceo-d 1,97 e o CPO-D 2,77. Verificou-se que 32,5% das crianças com síndrome de Down eram saudáveis, 65% com gengivite e 2,5% com periodontite e, no grupo controle, 50% foram saudáveis e 50% mostraram gengivite. Os resultados evidenciaram que a população de cocos cariogênicos foi similar entre pacientes portadores ou não de síndrome de Down. Concluiu-se que a ocorrência de cárie em crianças com síndrome de Down foi maior nos dentes permanentes comparadas com o grupo controle, enquanto que na dentição decídua a ocorrência de cárie foi maior no grupo controle, enquanto que as condições periodontais foram semelhantes entre os dois grupos.

Características Físico-Químicas, energéticas e desempenho da fibra de coco na sorção de óleo diesel e biodiesel

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Status of Aceria guerreronis Keifer (Acari: Eriophyidae) as a Pest of Coconut in the State of Sao Paulo, Southeastern Brazil

The coconut mite, Aceria guerreronis Keifer, is one of the main pests of coconut palms (Cocos nucifera) in northeastern Brazil. The objective of this study was to evaluate the levels of the coconut mite and other mites on coconut palms in the state of So Paulo and to estimate the possible role of predatory mites in the control of this pest. The effect of cultivated genotypes and sampling dates on the mite populations was also estimated. We sampled attached fruits, leaflets, inflorescences, and fallen fruits. The coconut mite was the main phytophagous mite found on attached and fallen fruits, with average densities of 110.0 and 20.5 mites per fruit, respectively. The prevalent predatory mites on attached and fallen fruits were Proctolaelaps bulbosus Moraes, Reis & Gondim Jr. and Proctolaelaps bickleyi (Bram), both Melicharidae. On leaflets, the tenuipalpids Brevipalpus phoenicis (Geijsks) and Tenuipalpus coyacus De Leon and the tetranychid Oligonychus modestus (Banks) were the predominant phytophagous mites. On both leaflets and inflorescences, the predominant predatory mites belonged to the Phytoseiidae. Neoseiulus baraki (Athias-Henriot) and Neoseiulus paspalivorus (De Leon), predators widely associated with the coconut mite in northeastern Brazil and several other countries, were not found. The low densities of the coconut mite in So Paulo could be related to prevailing climatic conditions, scarcity of coconut plantations (hampering the dispersion of the coconut mite between fields), and to the fact that some of the genotypes cultivated in the region are unfavorable for its development.

Can the red palm mite threaten the Amazon vegetation?

The red palm mite Raoiella indica Hirst (Tenuipalpidae) was first reported in the New World in 2004, dispersing quickly and widely while adopting new plant species as hosts. Since then, it has caused severe damage in this region, especially to coconut (Cocos nucifera L.). It was first found in Brazil in 2009, in the northern Amazonian state of Roraima. In the present study, native and introduced plants were sampled between March 2010 and February 2011 in sites of the 15 Roraima municipalities, to estimate its distribution and the associated mite fauna. In addition, monthly samples were taken from a coconut plantation in Mucajai throughout the same period, for an initial appraisal of the levels R. indica could reach. It was found in 10 municipalities, on 19 plant species of four families. Six species are reported for the first time as hosts. Among the associated predators, 89.1% were Phytoseiidae, most commonly Amblyseius largoensis (Muma), Iphiseiodes zuluagai Denmark & Muma and Euseius concordis (Chant). The highest densities of R. indica, 1.5 and 0.35 mites/cm2 of leaflet (approx total of 331 and 77 mites/leaflet), were reached respectively in March 2010 and February 2011. The highest density of phytoseiids on coconut (0.009 mites/cm2 or about 2 mites/leaflet) was reached in November 2010. The average densities of R. indica recorded for Roraima were comparable to those reported for countries in which the mite is reportedly economically damaging. The dispersal of R. indica through the Amazon forest may result in damage to cultivated and native palms, and plants of other families, if the projected increase in both the frequency and the severity of drought events occurs. Parts of the Amazon have undergone periods of low rainfall, a condition that appears to favour the biology of this mite. Its eventual arrival to northeastern Brazil may result in heavy economic and ecological losses.

Study of adsorption isotherms of green coconut pulp

Brazil is considered one of the largest producers and consumers of tropical fruits. Green coconut (Cocos nucifera L.) stands out not only for its production and consumption, but also for the high amount of waste produced by coconut water industry and in natura consumption. Therefore, there is a need for utilization of this by-product. This study aims to study the adsorption isotherms of green coconut pulp and determine its isosteric heat of sorption. The adsorption isotherms at temperatures of 30, 40, 50, 60, and 70 °C were analyzed, and they exhibit type III behavior, typical of sugar rich foods. The experimental results of equilibrium moisture content were correlated by models present in the literature. The Guggenheim, Anderson and De Boer (GAB) model proved particularly good overall agreement with the experimental data. The heat of sorption determined from the adsorption isotherms increased with the decrease in moisture content. The heat of sorption is considered as indicative of intermolecular attractive forces between the sorption sites and water vapor, which is an important factor to predict the shelf life of dried products.

Slope stability analysis of the Pacaya Volcano, Guatemala, using limit equilibrium and finite element method

The Pacaya volcanic complex is part of the Central American volcanic arc, which is associated with the subduction of the Cocos tectonic plate under the Caribbean plate. Located 30 km south of Guatemala City, Pacaya is situated on the southern rim of the Amatitlan Caldera. It is the largest post-caldera volcano, and has been one of Central America’s most active volcanoes over the last 500 years. Between 400 and 2000 years B.P, the Pacaya volcano had experienced a huge collapse, which resulted in the formation of horseshoe-shaped scarp that is still visible. In the recent years, several smaller collapses have been associated with the activity of the volcano (in 1961 and 2010) affecting its northwestern flanks, which are likely to be induced by the local and regional stress changes. The similar orientation of dry and volcanic fissures and the distribution of new vents would likely explain the reactivation of the pre-existing stress configuration responsible for the old-collapse. This paper presents the first stability analysis of the Pacaya volcanic flank. The inputs for the geological and geotechnical models were defined based on the stratigraphical, lithological, structural data, and material properties obtained from field survey and lab tests. According to the mechanical characteristics, three lithotechnical units were defined: Lava, Lava-Breccia and Breccia-Lava. The Hoek and Brown’s failure criterion was applied for each lithotechnical unit and the rock mass friction angle, apparent cohesion, and strength and deformation characteristics were computed in a specified stress range. Further, the stability of the volcano was evaluated by two-dimensional analysis performed by Limit Equilibrium (LEM, ROCSCIENCE) and Finite Element Method (FEM, PHASE 2 7.0). The stability analysis mainly focused on the modern Pacaya volcano built inside the collapse amphitheatre of “Old Pacaya”. The volcanic instability was assessed based on the variability of safety factor using deterministic, sensitivity, and probabilistic analysis considering the gravitational instability and the effects of external forces such as magma pressure and seismicity as potential triggering mechanisms of lateral collapse. The preliminary results from the analysis provide two insights: first, the least stable sector is on the south-western flank of the volcano; second, the lowest safety factor value suggests that the edifice is stable under gravity alone, and the external triggering mechanism can represent a likely destabilizing factor.

A Surface Displacement Analysis for Volcan Pacaya from October 2001 through March 2013 by Means of 3-D Modeling of Precise Position GPS Data

Volcán Pacaya is one of three currently active volcanoes in Guatemala. Volcanic activity originates from the local tectonic subduction of the Cocos plate beneath the Caribbean plate along the Pacific Guatemalan coast. Pacaya is characterized by generally strombolian type activity with occasional larger vulcanian type eruptions approximately every ten years. One particularly large eruption occurred on May 27, 2010. Using GPS data collected for approximately 8 years before this eruption and data from an additional three years of collection afterwards, surface movement covering the period of the eruption can be measured and used as a tool to help understand activity at the volcano. Initial positions were obtained from raw data using the Automatic Precise Positioning Service provided by the NASA Jet Propulsion Laboratory. Forward modeling of observed 3-D displacements for three time periods (before, covering and after the May 2010 eruption) revealed that a plausible source for deformation is related to a vertical dike or planar surface trending NNW-SSE through the cone. For three distinct time periods the best fitting models describe deformation of the volcano: 0.45 right lateral movement and 0.55 m tensile opening along the dike mentioned above from October 2001 through January 2009 (pre-eruption); 0.55 m left lateral slip along the dike mentioned above for the period from January 2009 and January 2011 (covering the eruption); -0.025 m dip slip along the dike for the period from January 2011 through March 2013 (post-eruption). In all bestfit models the dike is oriented with a 75° westward dip. These data have respective RMS misfit values of 5.49 cm, 12.38 cm and 6.90 cm for each modeled period. During the time period that includes the eruption the volcano most likely experienced a combination of slip and inflation below the edifice which created a large scar at the surface down the northern flank of the volcano. All models that a dipping dike may be experiencing a combination of inflation and oblique slip below the edifice which augments the possibility of a westward collapse in the future.

Insoluble residues of the fine-grained sediments from DSDP Leg 67 Holes

Insoluble residues of Late Cretaceous to Quaternary deep-sea samples from slope, trench, and oceanic plate sites south of Guatemala were examined, specifically for the distribution of clay minerals in the <2-µm fraction and of silt grains in the 20-63-µm fraction. Widespread "oceanic" particles (biogenic opal, rhyolitic glass) and their diagenetic products (smectite, clinoptilolite, heulandite) were distinguished from terrigenous material - illite, kaolinite, chlorite, plagioclase, quartz, and heavy minerals. The main results of this investigation are: (1) At Site 494 on the slope immediately adjacent to the trench, terrigenous supplies testify to a slope position of the whole sequence back to the Late Cretaceous. (2) At Site 495 on the Pacific Cocos Plate, "oceanic" and terrigenous sedimentation are clearly separated. Whereas the pelagic sedimentation prevailed in the early Miocene, terrigenous minerals appeared in the middle Miocene in the clay fraction, and in the early Pliocene in the coarse silt fraction. These terrigenous supplies are interpreted as having been transported by suspension clouds crossing the slope and even the trench. The alternative, however, an eolian transport, cannot be excluded.