101 research outputs found
Evaluation of Bio Briquettes made from Musa acuminata Colla, Musa acuminata and Musa balbisiana Silk, and Citrus reticulata and Citrus sinensis Peels
Accumulation of food waste and the burning of coal emit harmful chemicals which contribute to environmental problems such as climate change and global warming. These also risk the health of people, which causes deaths. Briquettes help improve and preserve the environment by lessening food waste and coal emissions. This study aims to determine the best treatment for briquettes to help disadvantaged communities and alleviate the adverse effects on the environment and health. A combination of banana (Musa acuminata Colla (AA Group) \u27Lakatan\u27 and Musa acuminata Ă M. balbisiana (AAB Group) \u27Silk\u27, and orange (Citrus Ă reticulata and Citrus Ă sinensis) peels were used as bases for the briquettes. Sawdust also served as a controlled treatment, and two different binder treatments were also used, namely paper pulp and cassava starch. The briquettes\u27 quality was tested based on their density, burning rate, ignition time, and efficiency (Water Boiling Test). One-way Multivariate Analysis of Variance (One-way MANOVA), Shapiro-Wilk Normality Test and Leveneâs Homogeneity of Variances Test, One-way ANOVA, Post-Hoc Test, specifically Tukeyâs LSD were then used to analyze the gathered results. Results revealed that the best briquettes are orange & cassava (density), banana & paper (burning rate), sawdust & cassava (ignition), and sawdust & cassava (efficiency). The findings indicate that the best briquettes were sawdust & cassava (most efficient in Water Boiling Test and fastest to ignite) and banana & paper (lowest burning rate) briquettes. Additionally, the findings suggest different production practices
Phylogeography of a successful aerial disperser: the golden orb spider Nephila on Indian Ocean islands
Abstract Background The origin and diversification patterns of lineages across the Indian Ocean islands are varied due to the interplay of the complex geographic and geologic island histories, the varying dispersal abilities of biotas, and the proximity to major continental landmasses. Our aim was to reconstruct phylogeographic history of the giant orbweaving spider (Nephila) on western Indian Ocean islands (Madagascar, Mayotte, RĂ©union, Mauritius, Rodrigues), to test its origin and route of dispersal, and to examine the consequences of good dispersal abilities for colonization and diversification, in comparison with related spiders (Nephilengys) inhabiting the same islands, and with other organisms known for over water dispersal. We used mitochondrial (COI) and nuclear (ITS2) markers to examine phylogenetic and population genetic patterns in Nephila populations and species. We employed Bayesian and parsimony methods to reconstruct phylogenies and haplotype networks, respectively, and calculated genetic distances, fixation indices, and estimated clade ages under a relaxed clock model. Results Our results suggest an African origin of Madagascar Nephila inaurata populations via Cenozoic dispersal, and the colonization of the Mascarene islands from Madagascar. We find evidence of gene flow across Madagascar and Comoros. The Mascarene islands share a common 'ancestral' COI haplotype closely related to those found on Madagascar, but itself absent, or as yet unsampled, from Madagascar. Each island has one or more unique haplotypes related to the ancestral Mascarene haplotype. The Indian Ocean N. inaurata are genetically distinct from the African populations. Conclusions Nephila spiders colonized Madagascar from Africa about 2.5 (0.6-5.3) Ma. Our results are consistent with subsequent, recent and rapid, colonization of all three Mascarene islands. On each island, however, we detected unique haplotypes, consistent with a limited gene flow among the islands subsequent to colonization, a scenario that might be referred to as speciation in progress. However, due to relatively small sample sizes, we cannot rule out that we simply failed to collect Mascarene haplotypes on Madagascar, a scenario that might imply human mediated dispersal. Nonetheless, the former interpretation better fits the available data and results in a pattern similar to the related Nephilengys. Nephilengys, however, shows higher genetic divergences with diversification on more remote islands. That the better disperser of the two lineages, Nephila, has colonized more islands but failed to diversify, demonstrates how dispersal ability can shape both the patterns of colonization and formation of species across archipelagos.</p
Diet of the sea anemone Anthopleura nigrescens: composition and variation between daytime and nighttime high tides
Tectonic events, continental intraplate volcanism, and mantle plume activity in northern Arabia: constraints form geochemistry and Ar-Ar dating of Syrian lavas
New (40)Ar/(39)Ar ages combined with chemical and Sr, Nd, and Pb isotope data for volcanic rocks from Syria along with published data of Syrian and Arabian lavas constrain the spatiotemporal evolution of volcanism, melting regime, and magmatic sources contributing to the volcanic activity in northern Arabia. Several volcanic phases occurred in different parts of Syria in the last 20 Ma that partly correlate with different tectonic events like displacements along the Dead Sea Fault system or slab break-off beneath the Bitlis suture zone, although the large volume of magmas and their composition suggest that hot mantle material caused volcanism. Low Ce/Pb (<20), Nb/Th (<10), and Sr, Nd, and Pb isotope variations of Syrian lavas indicate the role of crustal contamination in magma genesis, and contamination of magmas with up to 30% of continental crustal material can explain their (87)Sr/(86)Sr. Fractionation-corrected major element compositions and REE ratios of uncontaminated lavas suggest a pressure-controlled melting regime in western Arabia that varies from shallow and high-degree melt formation in the south to increasingly deeper regions and lower extents of the beginning melting process northward. Temperature estimates of calculated primary, crustally uncontaminated Arabian lavas indicate their formation at elevated mantle temperatures (T(excess) similar to 100-200 degrees C) being characteristic for their generation in a plume mantle region. The Sr, Nd, and Pb isotope systematic of crustally uncontaminated Syrian lavas reveal a sublithospheric and a mantle plume source involvement in their formation, whereas a (hydrous) lithospheric origin of lavas can be excluded on the basis of negative correlations between Ba/La and K/La. The characteristically high (206)Pb/(204)Pb (similar to 19.5) of the mantle plume source can be explained by material entrainment associated with the Afar mantle plume. The Syrian volcanic rocks are generally younger than lavas from the southern Afro-Arabian region, indicating a northward progression of the commencing volcanism since the arrival of the Afar mantle plume beneath Ethiopia/Djibouti some 30 Ma ago. The distribution of crustally uncontaminated high (206)Pb/(204)Pb lavas in Arabia indicates a spatial influence of the Afar plume of similar to 2600 km in northward direction with an estimated flow velocity of plume material on the order of 22 cm/a
Assessing human diet and movement in the Tongan maritime chiefdom using isotopic analyses.
The rise of stratified societies fundamentally influences the interactions between status, movement, and food. Using isotopic analyses, we assess differences in diet and mobility of individuals excavated from two burial mounds located at the `Atele burial site on Tongatapu, the main island of the Kingdom of Tonga (c. 500 - 150 BP). The first burial mound (To-At-1) was classified by some archaeologists as a commoner's mound while the second burial mound (To-At-2) was possibly used for interment of the chiefly class. In this study, stable isotope analyses of diet (ÎŽ13C, ÎŽ15N, and ÎŽ34S; n = 41) are used to asses paleodiet and 87Sr/86Sr ratios (n = 30) are analyzed to investigate individual mobility to test whether sex and social status affected these aspects of life. Our results show significant differences in diet between burial mounds and sexes. Those interred in To-At-2 displayed lower ÎŽ13C values, indicating they ate relatively more terrestrial plants (likely starchy vegetable staples) compared with To-At-1 individuals. Females displayed significantly lower ÎŽ15N values compared with males within the entire assemblage. No differences in ÎŽ34S values were observed between sexes or burial mound but it is possible that sea spray or volcanism may have affected these values. One individual displayed the strontium isotopic composition representative of a nonlocal immigrant (outside 2SD of the mean). This suggests the hegemonic control over interisland travel, may have prevented long-term access to the island by non-Tongans exemplifying the political and spiritual importance of the island of Tongatapu in the maritime chiefdom
Occupational eye protection using Augmented Reality: a proof of concept
Eyes can be exposed to very small and bright light sources during occupational time, such as LEDs, welding arcs and lasers. Such light sources produce an accident-generating glare. In addition, the blue part of their spectrum and their high radiance make the operatorâs retina at risk for the blue-light hazard. Filters protecting workers eyes tend to make lose the perception of the environment and task, and coloured protective glasses prevent from visible laser hazards but impair seeing alignment spots. An Augmented Reality system was investigated as a widespread and low-cost way to protect the operatorâs eyes without impairing environment perception. It is made using a Virtual Reality helmet holding a smartphone, whose camera replaces the operatorâs eyes. Real-time image processing allows operators to work safely on LEDs in operation, welding arcs and lasers. The user can see what he/she is doing while avoiding occupational exposure and glare. With visual ergonomics in mind, this system proves to be a potentially useful type of personal protective equipment against such bright light sources. In addition, it offers the ability to detect very near infrared laser spots
O-band 10-Gb/s operation of a reflective semiconductor optical amplifier based self-seeded transmitter for optical access applications
New applications emerge in the optical access for WDM PON colourless transmitters based on RSOA. Previous works have shown that 10 Gb/s operation can be reached in the C-band with such transmitters. Yet trade-offs are necessary when chromatic dispersion and, consequently, link length enter the equation. We discuss here such impairments using both experimental data and simulation results. We present also new experimental data with interesting performance in the O-band
Control of Pythium spp. root colonization in tomato soilless culture through chlorination of water storage tank
International audienceFungal and Oomycete plant diseases cause economically important losses in soilless cultures by affecting both yield and quality of productions. In these systems, the irrigation water is the main source of introduction of pathogenic microorganisms whose spreading is enhanced by the recycling of the nutrient solution, increasing thus the risk of root disease. To control the disease development, a chemical treatment through chlorination of water supplies was used in this study. The present experiment was conducted over a period of three years during which water and root samples were collected yearly in 8 to 13 tomato soilless greenhouses (8 greenhouses in year 1 and 13 in years 2 and 3). In control storage tanks, the water added to the nutrient solutions was frequently contaminated by Pythium spp. Contamination rates ranged from 5 to 30 Pythium cfu L-1 but were reduced to 0 to 3 cfu L-1 after the chlorination treatment of the water. However, these contamination levels were lower than those detected in the flowing nutrient solution samples: around 50 to 150 Pythium cfu L-1. During winter, roots of tomato plants in control conditions were weakly colonized by Pythium spp. (below 50 cfu g-1 of roots). These values dramatically increased during spring and summer; around 200 and 600 to 800 cfu were respectively detected per gram of roots. No root colonization by Pythium spp. was detected in winter after the chlorination treatment in the solutions; the colonization level reached around 50 cfu g-1 of roots in spring and 150 to 200 cfu g-1 of roots in summer. In conclusion, the chlorination treatment experienced here has been shown to be effective for the disinfection in the solutions and to have a key impact in reducing and delaying the root colonization by Pythium spp. Nevertheless, this treatment has the disadvantage of eliminating not only harmful but also beneficial indigenous microorganisms
Inoculation by antagonistic bacteria of slow-filtration unit for soilless cultures: Consequences on microbial communities colonizing the nutrient solutions
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Functional hemispherotomy in the treatment of drug-resistant epilepsy: a clinical case
Though brain hemiatrophy is not among the leading causes of symptomatic epilepsy; the problem remains important and is of great practical interest to neurologists and neurosurgeons in Russia. In this article; we present an example of successful surgical treatment of Dyke-Davidoff-Masson syndrome. Here; functional hemispherotomy was performed in a 22 years old female patient; as a result; the occurrence and intensity of epileptic seizures decreased. This clinical case provides hope for this procedure to show even better results if performed in early childhood
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