Metal Drums Research Articles

Traditional Smoking Processes of Bushmeat in Congo (Brazzaville)

To analyze the traditional methods of smoking bushmeat in rural Congolese environment, a survey and physical measurements have been conducted within the Conkouati-Douli National Park (PNCD), Department of Kouilou. The study involved two parts: a survey of 52 hunters selected in a random in a village in this protected area, and physical measurements associated with smoking process. The results indicate that the operations before the game smoking trimming were cutting, skinning and flushing. Smoking was affected by way of a metal drum containing a hurdle and a fireplace. The amount of wood used was an average of 8.6 kg, quantity varied according to species. The average duration of smoking was about 6 hours 30 minutes per day. The air temperature differed as measured on the gate and the hurdle. However, the minima temperatures were recorded at the end of cooking; however, the maxima were found between one hour and two hours of smoking. In conclusion, processes of transformation of bushmeat fresh in meat smoke in forest Congolese are still rudimentary, thus calling for the completion of the work of technological innovation.

Does targeting key‐containers effectively reduce Aedes aegypti population density?

The elimination of Aedes aegypti breeding sites has been broadly adopted worldwide to keep vector population density below a critical threshold. We observed the effectiveness of targeting the most productive containers on adult A. aegypti females density, which was evaluated weekly. Adult mosquitoes were collected weekly over 55 weeks and pupal surveys were done in intervals of 4 months to determine container productivity and guidelines for interventions. Pupal surveys indicated that water tanks (72% of pupae in first survey) and metal drums (30.7% of pupae in second survey) were the most productive container types. We observed a dramatic but short-term decrease in weekly adult female A. aegypti density after covering 733 water tanks with nylon net. A long-term decrease in female adult population density was achieved only when we covered both water tanks and metal drums. Overall, pupae abundance and pupae standing crop diminished after netting water tanks and metal drums. Pupae per person, per hectare and per house decreased gradually between the first and the third pupal surveys, suggesting that targeting the most productive container types (water tanks and metal drums) produced a reduction in adult population density and infestation levels. Overall, targeting the most productive container types caused the adult mosquito density to decrease over time, supporting the assumption that this intervention is an effective tool for dengue control. However, this effect was observed only when both water tanks and metal drums were covered, possibly due to the functional similarity between these container types, which are large, often shaded, perennial water storage containers.

Heat transfer and energy consumption in the freezing of guava pulp in large containers

Abstract The heat transfer process, including the convective transfer coefficients (h), freezing times and power consumption, was evaluated during the air blast freezing of 600 kg of guava pulp. Three packaging configurations were tested: plastic boxes (34 L), buckets (20 L) and metal drums (200 L). The air velocity inside the freezer tunnel was measured at several points, and sensors were installed to monitor the temperature. The heat infiltration from external ambient air was also verified. Correlations of the Nusselt number versus the Reynolds and Prandtl numbers were used to estimate the convective heat transfer coefficients according to the configuration of the systems. The coefficients were applied to freezing-time prediction models. The h values and consequent freezing time prediction were found to be more precise for the packaging in the bucket configuration. For the drum configuration, the correlation that considered the turbulence factor effects was found to be satisfactory. In the box configuration, the correlation produced good results only for the boxes located in the central area of the stack. The results indicate that the correlations may be applicable to the analysis and the differences explained by airflow and the difficulty of maintaining constant heat flow on the surfaces.

Absolute Bodies: The Video Puppets of Tony Oursler

Absolute Bodies: The Video Puppets of Tony Oursler

Situation épidémiologique de la fièvre jaune au Burkina Faso de 2003 à 2008

Despite the existence of antiamaril vaccine in the routine Expanded Program of Immunization (EPI) in Burkina Faso, yellow fever cases still occur in the country. In collaboration with WHO, the national health authorities set up a surveillance system through the national reference laboratory in Centre Muraz (Bobo-Dioulasso). All samples of feverish icterus cases of the 63 health districts of the country were analysed in this lab for M Immunoglobulin using Enzyme Linked Immunosorbent Assay (Elisa). Positive Elisa samples were sent to Pasteur Institute of Dakar (Senegal) for confirmation using a Reverse Transcriptase Polymerase Chain Reaction (RT-PCR) assay. From 2003 to 2005, the number of confirmed cases of yellow fever was respectively of 1/413 (0.24%), 14/616 (2.27%) and 19/618 (3.07%). This increasing of the proportion was statistical different. Then, from 2006 to 2008, the confirmed case proportion was respectively 0.35%, 0.27 and 0.54% without significant difference (P = 0.69). The entomological investigations conducted in 2004 in Bobo-Dioulasso showed that the water pots constitute 48.11% mosquitoes lodgings, followed by metal drums with a strong representation of Culex quinquefasciatus (48.7%), followed by Aedes aegypti (43.3%), as vectors in domestic areas with sectorial variations. These results suggest that more attention must be paid by the national health authorities and international community regarding this disease.

Dancing neurons, complex beats

Dancing neurons, complex beats

Traditional processing, microbiological, physiochemical and sensory characteristics of kwete, a Ugandan fermented maize based beverage

A survey was conducted to document the production methods of Kwete, a Ugandan fermented beverage in selected divisions in Kampala districts, Uganda. Microbial numbers in raw materials and during fermentation were enumerated using standard methods. Changes in selected physiochemical parameters: pH, titratable acidity (TA), ethanol and total soluble solids (TSS) were monitored at 24-hrs interval during 72hrs fermentation.Organoleptic properties of Kwete were also solicited from the producers. Similarities in raw material preparation and production techniques for Kwete were observed among the producers. Kwete was mainly produced from a mixture of maize and malted millet flour. All producers fermented the maize flours to produce raw sourdough for 24 hrs and roasted it before Kwete production. Fermentation was carried at ambient temperature in metallic drums. The duration of fermentation varied between 24 and72 hrs. Most households (80%) consumed Kwete within 24-48 hrs of fermentation. Coliforms, Yeasts and Lactic Acid Bacteria (LAB) numbers in maize flour and roasted sourdough varied between 1.59 and 5.24 log cfu-1. Yeasts and LAB numbers in raw sourdough and malted millet flour varied between 4.48 and 8.45 log cfu -1. No coliforms were detectable in raw sourdough. LAB numbers increased from 5.31 to 7.36 log cfu -1 during fermentation. Yeasts increased from 4.44 to 5.60 log cfu -1. Coliforms disappeared within 24 hrs of fermentation. The pH of maize flour droppedfrom pH 6.1 to 4.1 during sourdough production but increased to 4.89 during paste preparation. The final pH attained after 72 hrs of fermentation was 3.35. The TA increased from 0.84 to 1.43 % lactic acid. The TSS decreased from 9.02 to 5.87 o Brix. Ethanol content in Kwete increased from 4.85 to 13.30 % v/ v during fermentation. The various phases in Kwete production contribute significantly to the microorganisms involved in the fermentation. The high microbial numbers in addedmalted millet flour indicated that it is an important source of fermentationmicroorganisms during Kwete production.

Ammoniation of rice straw using poultry litter: Effect on nutrient composition and patholgenic microbial flora

La valeur nutritive et la flore microbienne pathogene de la paille de riz traitee a la litiere de volaille dans un essai factoriel 5x3x3 a ete evaluee a l’Universite Abubakar Tafawa Balewa, a Bauchi, au Nigeria. La paille de riz a ete melangee avec la litiere de volaille (RSPL) dans cinq proportions differentes 5:5, 6:4, 7:3, 8:2 et 9:1. L’eau a ete melangee avec chacun des RSPL (1-5) dans trois proportions differentes, 50:50, 60:40 et 70:30, respectivement. Les melanges ont ete conserves dans des futs metalliques etanche pendant 7, 14 et 21 jours.. La masse microbienne par gramme (UFC/g) etait significativement (P facon significative (P The nutritive value and pathogenic microbial flora of poultry litter treated rice straw in a 5x3x3 factorial trial was conducted at the Abubakar Tafawa Balewa University, Bauchi, Nigeria. Rice straw was mixed with poultry litter (RSPL) in five different ratios; 5:5, 6:4, 7:3, 8:2 and 9:1. Water was mixed with each of the RSPL (1-5) in three different proportions; 50:50, 60:40 and 70:30 respectively. The mixtures were kept in air-tight metal drums for treatment periods of 7, 14 and 21 days respectively. The colony forming unit per gram (CFU/g) was significantly (P while the CF and CFU/g decreased with days of treatment. It may be concluded that treating rice straw with poultry litter can improve the nutritive value while at the same time reduce the pathogenic microorganisms of the treated straw. An equal proportion of crop residue to poultry litter with an equal amount of water is required to enhance treatment. Treatment period of 21 days is required for effective treatment making the material safe for feeding to livestoc.

Ignition source static electricity: Incident investigation

Static electricity still represents a frequent ignition source when flammable liquids or combustible powders are handled and processed in industry. The present report deals with the investigation of an incident which occurred during splash filling 200 liter metal drums with isopropyl acetate. Although from the point of view of static electricity isopropyl acetate belongs to the group of liquids with high conductivity, the experimentally in situ determined charge to mass ratios and charging currents are extremely high compared to low conductivity liquids such as hydrocarbon fuels. The ignition of the isopropyl acetate vapors can also be explained if the metal drum was properly earthed. Since the drum had a highly insulating coating with a breakdown voltage of 1.1–1.9 kV the explosive atmosphere could also have been ignited by a discharge from the highly charge isolated liquid.

Practical 3-D Migration and Visualization for Accurate Imaging of Complex Geometries with GPR

Obtaining high-quality three-dimensional images that accurately represent target geometries is crucial for reliable interpretation of ground penetrating radar data. Dense data acquisition, three-dimensional migration processing, and visualization are needed to recognize complex target geometries. A novel implementation of the diffraction summation migration algorithm efficiently images three-dimensional geometries by utilizing the efficient properties of fast Fourier transforms to compute diffraction summations. The algorithm decomposes the diffraction summation calculations into spatial and temporal summations. The spatial summations are computed by convolving the data with two-dimensional convolution kernels computed from the three-dimensional point spread functions. Computation times are reduced by performing convolutions in the wavenumber domain using two-dimensional fast Fourier transforms. The migration aperture is easily adjusted in the algorithm to increase computational speeds and reduce processing artifacts associated with large amplitude spikes. Microsoft Visual Studio.NET and C# are used to create efficient and low-cost applications optimally designed for the processing and display of ground penetrating radar data. Migration algorithms are combined with volume rendering and visualization algorithms that utilize DirectX to visually recognize complex geometries in three-dimensions. A gravel test bed containing buried spheres, letters cut from metal sheets, pipes, and drums is imaged with dense and orthogonal 400 and [Formula: see text] ground penetrating radar surveys. A linear array composed of fourteen variably spaced spheres is used to empirically determine the resolution capabilities of commercial ground penetrating radar systems in favorable soils. In addition, letters cut from aluminum sheets are used to test imaging capabilities similar to those used to test human vision. Observed quarter-wavelength spatial resolutions are consistent with theoretical predictions. While horizontal slices work well for displaying horizontal objects, volume rendering is more effective for visualizing dipping objects. Increasing antenna frequency improves spatial resolution and produces less pronounced polarization differences between data acquired with orthogonal surveys.

A study of electrospun PVDF on PET sheet

PVDF (Kynar® 761) nanofibers were made by electrospinning with an external voltage of 6–10 kV, a traveling distance of 7–15 cm and a flow rate of 0.4–1 mL/h. Although the mean diameter of the fibers has not changed significantly, the conditions affected the change in diameter distribution. This was attributed to interactions, both attraction and repulsion, between the positive charges on the polymer solutions and the electrically grounded collector. Higher voltages and traveling distance increased the level of attraction between the positive charge on the polymer solution and the electrically grounded collector, resulting in a narrow diameter distribution. In addition, a high flow rate allowed a high population of uniformly charged solutions to travel to the grounded collector, which resulted in a narrow diameter distribution. The optimum conditions for electrospinning of PVDF in DMAc/acetone (3/7 by wt) were a collector voltage of 6 kV, a syringe tip to collector of 7 cm, a flux rate of 0.4 mL/h and 10 kV, 10 cm, 1 mL/h. Since PVDF is widely used as a filtration membrane, it was electrospun on a PET support with a rotating drum as a grounded collector. Surprisingly, some straight nanofibers were separated from the randomly deposited nanofibers. The straight nanofiber area was transparent, while the randomly deposited nanofiber area was opaque. Both straight nanofibers and aligned nanofibers could be obtained by manipulating the PET drum collector. These phenomena were not observed when the support was changed to an Al sheet. This suggests that a pseudo dual collector was generated on the PET sheet. No negative charge was created because the PET sheet was not a conductive material. However, less charge was created when the sheet was not perfectly attached to the metal drum. Hence, the nanofibers jumped from one grounded site to the nearest one, yielding a straight nanofiber.

Variation in Aedes aegypti(Diptera: Culicidae) container productivity in a slum and a suburban district of Rio de Janeiro during dry and wet seasons

Seasonal variation in container productivity and infestation levels by Aedes aegypti were evaluated in two areas with distinct levels of urbanization degrees in Rio de Janeiro, a slum and a suburban neighborhood. The four most productive containers can generate up to 90% of total pupae. Large and open-mouthed containers, such as water tanks and metal drums, located outdoors were the most productive in both areas, with up to 47.49% of total Ae. aegypti pupae collected in the shaded sites in the suburban area. Water-tanks were identified as key containers in both areas during both the dry and rainy seasons. Container productivity varied according to seasons and urbanization degree. However, the mean number of pupae per house was higher in the suburban area, but not varied between seasons within each area (P > 0.05). High infestation indexes were observed for both localities, with a house index of 20.5-21.14 in the suburban and of 9.56-11.22 in the urban area. This report gives potential support to a more focused and cost-effective Ae. aegypti control in Rio de Janeiro.

The economic impact of cowpea research in Senegal: an ex‐post analysis with disadoption

AbstractThis study evaluates the impact of a long‐term research collaboration between the Senegalese Institute for Agriculture Research (ISRA), and the Bean/Cowpea Collaborative Research Support Program (CRSP) funded by the U.S. Agency for International Development (USAID). Adoption of the primary outputs from this collaboration, a nonchemical cowpea storage method and two short‐season cowpea varieties, were tracked through a series of farmer interviews in 1996, 1997, and 2004 in the main cowpea growing area of Senegal. Combined with information from an impact assessment in the late 1980s, this study draws on ex‐post adoption data from most of the product life cycle for the storage technology. The 2004 survey found that 60.4% of cowpea production in the main cowpea growing area of Senegal is stored in metal drums and that 69% of households use this storage technology; ISRA/CRSP improved short season varieties were determined to account for 3.6% of cowpea production. Baseline economic analysis of the most recent survey data, which includes benefits and costs of the storage technology and improved varieties, reveal an IRR to donor funding of 13%. The benefits of these technologies appear to be evenly distributed in the rural population on the basis of gender and ethnic background. Comparison of the rates of technology adoption over time, however, reveals that use of the storage technology may be decreasing; inclusion of this technology disadoption trend reduces the IRR by only 0.4% from the baseline estimate. Overall, estimated returns reveal that this collaboration has been a good investment for the U.S. and Senegalese governments, and other donors.

Efficiency Enhancement of the Axial VIRCATOR

We present in this paper the particle-in-cell simulation results of a modified axial virtual cathode oscillator having a metallic drum of radius R1 placed coaxially inside the drift tube at a distance D1 from the foil anode. The enlarged parameter space permits control of the current transmitted to the collection plate, the net diode current, and the size of the electromagnetic emission and extraction regions. The geometry allows low-frequency radiation as well as high-frequency microwaves to leak out from the extraction region. The microwave content in the total electromagnetic power is found to be maximum when the drum is sufficiently close to the anode but far enough to allow the formation of a virtual cathode and permit a large emission region. The microwave power and efficiency also depend sensitively on the radius of the metallic drum. As the drum radius increases, the diode current and cutoff-frequency for transverse-magnetic (TM) modes increase while the extraction window shrinks in size. For parameter values studied, a peak locally time-averaged (over several periods) microwave power of 210 MW was obtained using a square voltage pulse of 250 kV at an efficiency of 7% while the peak-period averaged power was found to be 275 MW. In the absence of the drum, the peak locally time-averaged microwave power obtained was 93 MW at an efficiency of 3.3%

MANAGEMENT OF SPENT SEALED RADIOACTIVE SOURCES IN TURKEY

Spent radioactive sources (SRS) have been generated from industrial applications, research, and medicine in Turkey. In this study, management of SRS (Co, Cs) at Cekmece Waste Processing and Storage Facility (CWPSF) is described. Eleven Cs sources (total 851 GBq) and four Co sources (total 27.75 GBq) that had been used as levels and density gauges were conditioned. Reinforced metal drums (200 L in volume) and cement matrix were used for conditioning of these sources. In this way, greater confinement was achieved for long-term storage. Maximum dose rates at the surface of the conditioned waste package were determined. In addition to information about conditioning stages of the sources, various calculations that have been done for shielding are presented. Surface dose rates of the waste packages were 1.60 mSv h for Cs and 1.63 mSv h for Co. Measurements of the final waste packages were presented to fulfill the requirements (<2 mSv h) of transportation according to regulations for the safe transport of radioactive material.

Application of the pupal/demographic-survey methodology to identify the key container habitats ofAedes aegypti(L.) in Malindi district, Kenya

The pupal/demographic-survey methodology was evaluated in three coastal areas (one urban, one peri-urban and one rural) of Malindi district, Kenya, in attempts to identify the types of domestic container that are most productive for Aedes aegypti (L.) pupae. The results demonstrated the practicality and consistency of the methodology, as a tool both for identifying and guiding the targeted control of the most productive container habitats, and for determining the mean numbers of pupae/person, as measures of the risk of dengue transmission.Twenty-five types of container were identified indoors and 50 types outdoors. In total, only 4,178 pupae were seen indoors and 795 outdoors. Pupal productivity was dependent on the type, location and volume of the container and the season of the year. Metallic drums and jerricans contributed >70% of the pupae encountered indoors in the wet season whereas, in the rural area, plastic drums contributed 83.7% of all the larvae seen outdoors during the dry season. Container productivity was not consistent during the different surveys. The highest mean numbers of pupae/person (7.61) and of pupae/household (18.12) were recorded in the rural area.

Pupal-productivity surveys to identify the key container habitats ofAedes aegypti(L.) in Barranquilla, the principal seaport of Colombia

Surveys were conducted in three neighbourhoods of Barranquilla, the main seaport of Colombia, to identify, using counts of pupae in water containers during the wet and dry seasons, the most productive Aedes aegypti breeding sites. Overall, 3,433 premises were investigated in the wet season and 3,563 in the dry, representing, respectively, 82.3% and 84.6% of the total numbers of premises in the study areas. Despite a reasonably reliable supply of piped water, there were still some large storage containers for domestic water (cement ground tanks and plastic, metal and cement drums) in the area. Although such containers represented only 1.8%-16.3% of the total number of containers observed, they contributed 72.0%-78.2% and 65.0%-95.8% of the total Ae. aegypti pupal population in the three study neighbourhoods during the wet and dry seasons, respectively. In contrast, bottles represented 23.0%-88.9% of the total number of containers but produced no more than 0.1% of the total Ae aegypti pupal populations in these neighbourhoods. Other containers (tyres, vases, 'other discarded' and 'other used') generally produced only low numbers of pupae. In some settings, however, containers in the 'other discarded' category could contribute up to 19% of the total pupal population, and in one survey of one neighbourhood a single container in this category held 9.1% of all the pupae collected. These results, from a city where dengue fever is endemic, will help to focus local campaigns for Ae. aegypti source-reduction on the most productive categories of container.

Environmental Applications of Sub-Audio Magnetics

Sub-Audio Magnetics (SAM) is a method by which a total-field magnetic sensor may be used to simultaneously acquire both total magnetic intensity (TMI) and total-field electromagnetic induction (TFEMI) responses from buried metal. In situations where public safety is involved, regulators, such as the U.S. Environmental Protection Agency, can mandate the use of both magnetic and electromagnetic sensors for the detection of potentially hazardous items such as unexploded ordnance (UXO) and metal drums. SAM has now completed a program of evaluation and certification as a state-of-the-art technology, acceptable for application in the litigation-sensitive environmental hazard remediation market.During its certification program, SAM was applied to controlled U.S. test sites at the Aberdeen Proving Ground, Maryland, McKinley Range, Alabama, Waikoloa, Hawaii, and at the Newholme facility in Australia. It was also applied to situations in Montana where live UXO was present. In these demonstrations, a direct comparison was made between SAM results and common, state-of-the-art alternative geophysical detecting technologies. Based on demonstrations at these sites, it has been possible to quantify the key performance parameters: level of effort, detection performance as a function of depth and target size, false-alarm rejection achieved through dual-mode sensing, and the cost-benefit ratio of SAM compared with contemporary sensor technologies such as the Geonics EM61 and EM63 electromagnetic detectors, and G-tek’s TM-5EMU electromagnetic detector and TM-4 total field magnetometer.SAM has proven to be very successful in detecting a wide range of metallic UXO items to depths exceeding achievable detection by all contemporary sensors. In the Montana live sites, where the smallest item of UXO was a 76 mm projectile, false-alarm rates were reduced from 7 per UXO, using TMI only, to 0.7 per UXO using combined SAM TMI and TFEMI data, without diminishing the probability of UXO detection. Survey cost per hectare using SAM was determined to be less than one quarter that of conducting TMI plus EMI surveys separately.The application of SAM to extremely magnetic lava flows at Waikoloa in Hawaii showed that SAM cannot yet compete with the ground-balancing capability of the TM-5EMU in this environment. Advanced signal-processing development may reduce this present limitation.

ELIMINATION OF DENGUE BY COMMUNITY PROGRAMS USING MESOCYCLOPS(COPEPODA) AGAINST AEDES AEGYPTI IN CENTRAL VIETNAM

From September 2000 to June 2003, a community-based program for dengue control using local predacious copepods of the genus Mesocyclops was conducted in three rural communes in the central Vietnam provinces of Quang Nam, Quang Ngai, and Khanh Hoa. Post-project, three subsequent entomologic surveys were conducted until March 2004. The number of households and residents in the communes were 5,913 and 27,167, respectively, and dengue notification rates for these communes from 1996 were as high as 2,418.5 per 100,000 persons. Following knowledge, attitude, and practice evaluations, surveys of water storage containers indicated that Mesocyclops spp. already occurred in 3-17% and that large tanks up to 2,000 liters, 130-300-liter jars, wells, and some 220-liter metal drums were the most productive habitats for Aedes aegypti. With technical support, the programs were driven by communal management committees, health collaborators, schoolteachers, and pupils. From quantitative estimates of the standing crop of third and fourth instars from 100 households, Ae. aegypti were reduced by approximately 90% by year 1, 92.3-98.6% by year 2, and Ae. aegypti immature forms had been eliminated from two of three communes by June 2003. Similarly, from resting adult collections from 100 households, densities were reduced to 0-1 per commune. By March 2004, two communes with no larvae had small numbers but the third was negative; one adult was collected in each of two communes while one became negative. Absolute estimates of third and fourth instars at the three intervention communes and one left untreated had significant correlations (P = 0.009-< 0.001) with numbers of adults aspirated from inside houses on each of 15 survey periods. By year 1, the incidence of dengue disease in the treated communes was reduced by 76.7% compared with non-intervention communes within the same districts, and no dengue was evident in 2002 and 2003, compared with 112.8 and 14.4 cases per 100,000 at district level. Since we had similar success in northern Vietnam from 1998 to 2000, this study demonstrates that this control model is broadly acceptable and achievable at community level but vigilance is required post-project to prevent reinfestation.

Oxidation of soybean oil during storage of starch‐oil composites

AbstractThe oxidative deterioration of dry starch‐oil composites was investigated by chemical and sensory methods. The composites were stored at 37°C for 63 d, and changes in the hexanal content and odor attributes were monitored. Analysis of the extracted oil showed that the first run through the drum dryer presented higher hexanal concentrations than the subsequent runs. Starch‐oil composites from the first run though the drum dryer showed higher metal concentrations and higher odor ratings during storage time than the subsequent runs. There was a significant correlation between odor attributes and hexanal concentration in the first run. Since both the oxidation and the metal content were higher in the first run and decreased in further runs, we concluded that oxidation might have been induced by the presence of metal in the drum dryer. It is likely that during drum drying, the metal drum and knife surfaces became coated with soy oil, reducing both abrasion and metal contact with the product. Since many applications of the starch‐oil composite technology require drum drying, it will be necessary to take measures to minimize metal contamination of the product, perhaps by discarding the initial portion of product, which contains the most metal.