458 research outputs found

    Preparing Korean missionaries for cross-cultural effectiveness

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    https://place.asburyseminary.edu/ecommonsatsdissertations/1164/thumbnail.jp

    Vertical Profiles of Virus-Like Particles and Bacteria in the Water Column and Sediments of Chesapeake Bay, USA

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    Vertical profiles of virus-like particles (VLPs) and bacteria were determined by near-synoptic sampling through the water column and 15 to 25 cm into the sediment at 5 stations across the mouth of Chesapeake Bay, USA. VLPs were about 10 times more abundant in the pore water (grand mean = 3.6 x 10(8) VLPs ml(-1)) than in the water column (grand mean = 3.8 x 10(7) VLPs ml(-1)). Similarly, bacteria counts were about 3 times higher in the pore water (grand mean = 6.5 x 10(6) bacteria ml(-1)) than in the water column (grand mean = 2.4 x 10(6) bacteria ml(-1)). The virus to bacteria ratio (VBR) was greater in the pore water (range = 29 to 85) than in the water column (range = 12 to 17). The VER was lowest in the water-over-boxcore samples and variable in the pore water. Counts of VLPs and bacteria were positively correlated in the water column, although neither was correlated to chlorophyll a. In the water column, VLPs and bacteria counts exhibited significant differences among stations, with the highest values on the southern side of the Bay mouth. In the pore water, VLP abundance varied with depth and was negatively correlated to grain size. Bacteria abundance was highest at the sediment-water interface, decreased in the first cm of sediment, was uniform in the deeper horizons, and showed no significant relationship with grain size. Bacteria counts in pore water were not significantly different among stations. In contrast, VLP abundances in pore water were significantly different among stations, although they did not increase in abundance from north to south across the Bay mouth. as did counts of water-column VLPs. These are the first data indicating the abundance of VLPs below the surface layer of sediment in aquatic systems and demonstrate that VLPs are components of the sedimentary microbial community to at least 25 cm depth

    Extended Tailing of Bacteria Following Breakthrough at the Narrow Channel Focus Area, Oyster, Virginia

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    Extended tailing of low bacterial concentrations following breakthrough at the Narrow Channel focus area was observed for 4 months. Bacterial attachment and detachment kinetics associated with breakthrough and extended tailing were determined by fitting a one-dimensional transport model to the field breakthrough-tailing data. Spatial variations in attachment rate coefficient (k(f)) were observed under forced gradient conditions (i.e., k(f) decreased as travel, distance increased), possibly because of decreased bacterial adhesion with increased transport distance. When pore water velocity decreased by an order of magnitude at 9 days following injection, apparent bacterial attachment rate coefficients did not decrease with velocity as expected from filtration theory, but, instead, increased greatly for most of the wells. The coincidence of the increase in apparent attachment rate coefficient with the occurrence of protist blooms suggested-that the loss of bacteria from the aqueous phase during the protist blooms was not governed by filtration but rather was governed by predation. Simulations were performed to examine the transport distances achieved with and without detachment, using attachment and detachment rate coefficients similar to those obtained in this field study. Simulations that included detachment showed that transport distances of bacteria may significantly increase because of detachment under the conditions examined

    Numerical Computation on the Generation of CH3 and H Radicals by the Thermal Plasma Decomposition of Hydrocarbons

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    A two-dimensional numerical analysis on the thermal decomposition of methane (CH4) by Ar/H2 thermal plasmas has been carried out using a FLUENT code to nd out the effects of thermal plasma fields on the production rates of CH3 and H radicals during the CH4 decomposition process in a dc arc-jet diamond CVD. In the numerical analysis, the partial di erential equations describing conservations of mass, momentum, and energy as well as mass of individual chemical species are taken into account along with the K-epsilon turbulence model. The numerical calculations are performed in the following consecutive procedure. In the first step, the thermal plasma fields inside a reaction chamber are calculated from the inlet boundary conditions without considering chemical reactions. Uniform profiles of the plasma temperature and velocity at the torch exit are assumed as the inlet boundary conditions in this step. Next in the second calculation step, the chemical kinetic equations, involving 13 species and 25 reactions, are solved in the environment of the calculated two-dimensional plasma fields to give the concentration fields of all chemical species generated in the CH4 decomposition process. The calculated results show that the developed plasma elds inside the reaction chamber strongly depend on the reaction chamber geometry, and significantly affect the concentration fields and generation rates of the decomposed radicals, such as CH3 and H.Supported by the Korea Institute of Science and Technology Evaluation and Planning (KISTEP) in Kore

    Development and evaluation of a plant-based air filter system for bacterial growth control

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    We investigated a novel plant-based air filter system for bacterial growth control. The volatile components released from the experimental plant (Cupressus macrocarpa) were used as the basis of the bacterial growth control and inhibition. We monitored the effect of light on the gas exhausted from the system, and we found that the presence of light induced an increase in the O2 concentration and a decrease in the CO2 concentration in the exhaust gas. A variety of Gram-positive and -negative bacteria was used to elucidate the effect of the exhaust gas on bacterial growth. In the Bacillus subtilis cultivation aerated with the exhaust gas (batch mode), we observed a decrease in the specific growth rate (μ = 0.227 h-1) compared with the control experiments (0.257 h-1). The same result was observed for the Staphylococcus aureus cultivation aerated with the exhaust gas. In the case of Gram-negative bacterial cultivation aerated with the gas, no significant inhibitory effect of the exhaust gas on the bacterial growth was observed. When the number of bacteria (B. subtilis) in a continuous culture was varied at different aeration rates (between 50 to 200 mL/min) using the exhaust gas, a prominent inhibitory effect was observed. Preliminary gas analysis showed that the major inhibitory factors in the exhaust gas are α- and β-pinene and linalool. The results show that the air filter system used in this study could be applied not only as a methodological aspect for estimating antibacterial activity but also for bacteria control in a given system.Keywords: Plant-based biofilter, Cupressus macrocarpa, Bacillus subtilis, Staphylococcus aureus, α-pinene, β-pineneAfrican Journal of Biotechnology Vol. 12(16), pp. 2027-203

    Feature coordinate estimation by time differenced vision/GPS/INS

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    This paper proposes a multi-baseline method to estimate absolute coordinates of point clouds and the camera attitude parameter utilizing feature points in successive images. Conventionally, 3D map generation methodologies have been based on images acquired by aerial or land vehicles. Pixels corresponding to known landmarks are manually identified at first. Next, the coordinates are directly geo-referenced and automatically allocated to pixels with high-quality Global Positioning System (GPS) and Inertial Navigation System (INS). However, it is difficult to obtain accurate coordinates by the conventional methodology with low-cost GPS and INS. With camera positions and attitude parameters, image-based point clouds can be compensated accurately. A simulation was carried out to evaluate the performance of the proposed method

    Cumulative burden of metabolic syndrome and its components on the risk of atrial fibrillation:a nationwide population-based study

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    BackgroundThe metabolic syndrome (MetS) and its components are associated with the development of atrial fibrillation (AF). However, the impact of time-burden of MetS on the risk of AF is unknown. We investigated the effect of the cumulative longitudinal burden of MetS on the development of AF.MethodsWe included 2 885 189 individuals without AF who underwent four annual health examinations during 2009-2013 from the database of the Korean national health insurance service. Metabolic burdens were evaluated in the following three ways: (1) cumulative number of MetS diagnosed at each health examination (0-4 times); (2) cumulative number of each MetS component diagnosed at each health examination (0-4 times per MetS component); and (3) cumulative number of total MetS components diagnosed at each health examination (0 to a maximum of 20). The risk of AF according to the metabolic burden was estimated using Cox proportional-hazards models.ResultsOf all individuals, 62.4%, 14.8%, 8.7%, 6.5%, and 7.6% met the MetS diagnostic criteria 0, 1, 2, 3, and 4 times, respectively. During a mean follow-up of 5.3 years, the risk of AF showed a positive association with the cumulative number of MetS diagnosed over four health examinations: adjusted hazard ratios (HRs) with 95% confidence intervals (CIs) of 1, 2, 3, and 4 times compared to 0 times were 1.18 (1.13-1.24), 1.31 (1.25-1.39), 1.46 (1.38-1.55), and 1.72 (1.63-1.82), respectively; P for trend ConclusionsGiven the positive correlations between the cumulative metabolic burdens and the risk of incident AF, maximal effort to detect and correct metabolic derangements even before MetS development might be important to prevent AF and related cardiovascular diseases

    Takotsubo Cardiomyopathy: A Case of Persistent Apical Ballooning Complicated by an Apical Mural Thrombus

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    Takotsubo cardiomyopathy (TTC) is an infrequent cardiac syndrome characterized by acute onset chest pain with apical ballooning on echocardiography. It is often triggered by severe emotional or physical stress, and in contrast to acute myocardial infarction (AMI), the regional wall motion abnormality returns to normal within days. Here, we describe a 62-year-old female who presented with acute onset chest pain during treatment for a liver abscess. We presumed a diagnosis of AMI because of ST segment elevation on electrocardiography and elevated cardiac enzyme levels. However, the patient's coronary arteries were normal on angiography, and apical ballooning was seen on echocardiography. A diagnosis of TTC was made, and the patient was managed with intensive cardiopulmonary support using vasopressors in our hospital's medical intensive care unit. The patient's symptoms improved, but persistent severe left ventricular dysfunction was detected on follow-up echocardiography. After 5 weeks, a new apical mural thrombus appeared, and anticoagulation therapy was started. The apical ballooning persisted 3 months later, although the patient's overall ejection fraction was slightly improved. The apical thrombus was completely resolved without any embolic event. Non-adrenergic inotropics can be recommended in TTC with shock, and clinicians should keep in mind the potential risk of thrombus formation and cardioembolism
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