Measurement of flow speed in the channels of novel threadlike structures on the surfaces of mammalian organs

There have been several reports on novel threadlike structures (NTSs) on the surfaces of the internal organs of rats and rabbits since their first observation by Bonghan Kim in 1963. To confirm this novel circulatory function, it is necessary to observe the flow of liquid through the NTS as well as the structurally corroborating channels in the NTS. In this article, we report on the measurement of the flow speed of Alcian blue solution in the NTSs on the organ surfaces of rabbits, and we present electron microscopic images depicting the cribrous cross-section with channels. The speed was measured as 0.3 ± 0.1 mm/s, and the flow distance was up to 12 cm. The flow was unidirectional, and the phase contrast microscopic images showed that the NTSs were strongly stained with Alcian blue. The ultrastructure of the NTSs revealed by cryo-scanning electron microscopy and high-voltage electron microscopy showed that (1) there were cell-like bodies and globular clumps of matter inside the sinus of the channel with thin strands of segregated zones which is a microscopic evidence of the liquid flow, (2) the sinuses have wall structures surrounded with extracellular matrices of collagenous fibers, and (3) there exists a cribriform structure of sinuses. To understand the mechanism for the circulation, a quantitative analysis of the flow speed has been undertaken applying a simplified windkessel model. In this analysis, it was shown that the liquid flow through the NTSs could be due to peristaltic motion of the NTS itself. Baeckkyoung Sung and Min Su Kim contributed equally to this work.     

Young fire ant workers feign death and survive aggressive neighbors

Feigning death is a method of self-defense employed among a wide range of prey species when threatened by predator species. This paper reports on death-feigning behavior by the fire ant, Solenopsis invicta, during intraspecific aggression among neighboring fire ant workers. Days-old workers responded to aggression by death feigning, weeks-old workers responded by fleeing and months-old workers responded by fighting back. By feigning death, days-old workers were four times more likely to survive aggression than older workers. From a proximate perspective, retaliation by young workers against aggressive older workers is certain to fail. With their relatively soft exoskeleton, young workers would be prone to injury and death and unable to execute an effective attack of biting or stinging older workers with harder exoskeletons. From an ultimate perspective, death feigning allows young workers to survive and contribute to brood care and colony growth, both of which are essential to queen survival and fitness.     

Evaluation of non-point source pollution reduction by applying Best Management Practices using a SWAT model and QuickBird high resolution satellite imagery

This study evaluated the reduction e ect of non-point source pollution by applying best management practices (BMPs) to a 1.21 km2 small agricultural watershed using a SWAT (Soil andWater Assessment Tool) model. Two meter QuickBird land use data were prepared for the watershed. The SWAT was calibrated and validated using daily streamflow and monthly water quality (total phosphorus (TP), total nitrogen (TN), and suspended solids (SS)) records from 1999 to 2000 and from 2001 to 2002. The average Nash and Sutcli e model e ciency was 0.63 for the streamflow and the coe cients of determination were 0.88, 0.72, and 0.68 for SS, TN, and TP, respectively. Four BMP scenarios viz. the application of vegetation filter strip and riparian bu er system, the regulation of Universal Soil Loss Equation P factor, and the fertilizing control amount for crops were applied and analyzed.     

Assessment of physically-based and data-driven models to predict microbial water quality in open channels

In the present study,a physically-based hydraulic modeling tool and a data-driven approach using artificial neural networks (ANNs) were evaluated for their ability to simulate the fate and transport of microorganisms in a water system.To produce reliable data,a pipe network was constructed and a series of experiments using a fecal coliform indicator (Escherichia coli 15597) was conducted.For the physically-based model,morphological (pipe size,link length,slope,etc.) and hydraulic (flow rate) conditions were used as input variables,and for ANNs,water quality parameters (conductivity,pH,and turbidity) were used.Both approaches accurately described the fate and transport of microorganisms (physically-based model: correlation coefficient (R) in the range of 0.914 – 0.977 and ANNs: R in the range of 0.949 – 0.980),with the exception of one case at a low flow rate (q = 31.56 cm 3 /sec).This study also indicated that these approaches could be complementarily utilized to assess the vulnerability of water facilities and to establish emergency plans based on hypothetical scenarios.     

Disc size regulation in the brood cell building behavior of leaf-cutter bee, <Emphasis Type="Italic">Megachile tsurugensis</Emphasis>

The leaf-cutter bee, Megachile tsurugensis, builds a brood cell in a preexisting tunnel with leaf discs that she cuts in decreasing sizes and assembles them like a Russian matryoshka doll. By experimentally manipulating the brood cell, it was investigated how she regulates the size of leaf discs that fit in the brood cell’s internal volume. When the internal volume was artificially increased by removing a bulk of leaf discs, she decreased the leaf disc size, although increasing it would have made the leaf disc more fitting in the increased internal volume. As a reverse manipulation, when the internal volume was decreased by inserting a group of inner layers of preassembled leaf discs to a brood cell, she decreased the leaf disc size, so that the leaf disc could fit in the decreased internal volume. These results suggest that she uses at least two different mechanisms to regulate the disc size: the use of some internal memory about the degree of building work accomplished in the first and of sensory feedback of dimensional information at the construction site in the second manipulation, respectively. It was concluded that a stigmergic mechanism, an immediate sensory feedback from the brood cell changed by the building work, alone cannot explain the details of the bee’s behavior particularly with respect to her initial response to the first manipulation. For a more complete explanation of the behavior exhibited by the solitary bee, two additional behavioral elements, reinforcement of building activity and processing of dimensional information, were discussed along with stigmergy.     

Vaporization reduction characteristics of aqueous ammonia solutions by the addition of ethylene glycol, glycerol and glycine to the CO2 absorption process

Aqueous ammonia (NH₃) solution can be used as an alternative absorption for the control of CO₂ emitted from flue gases due to its high absorption capacity, fast absorption rate and low corrosion problem. The emission of CO₂ from iron and steel plants requires much attention, as they are higher than those emitted from power plants at a single point source. In the present work, low concentration ammonia liquor, 9 wt.%, was used with various additives to obtain the kinetic properties using the blast furnace gas model. Although a solution with a high ammonia concentration enables high CO₂ absorption efficiency, ammonium ions are lost as ammonia vapor, resulting in reduced CO₂ absorption due to the lower concentration of the ammonia absorbent. To decrease the vaporization of ammonia, ethylene glycol, glycerol and glycine, which contain more than one hydroxyl radical, were chosen. The experiments were conducted at 313 K similar to the CO₂ absorption conditions for the blast furnace gas model.     

Global warming potential factors and warming payback time as climate indicators of forest biomass use

A method is presented for estimating the global warming impact of forest biomass life cycles with respect to their functionally equivalent alternatives based on fossil fuels and non-renewable material sources. In the method, absolute global warming potentials (AGWP) of both the temporary carbon (C) debt of forest biomass stock and the C credit of the biomass use cycle displacing the fossil and non-renewable alternative are estimated as a function of the time frame of climate change mitigation. Dimensionless global warming potential (GWP) factors, GWP_bio and GWP_biouse, are derived. As numerical examples, 1) bioenergy from boreal forest harvest residues to displace fossil fuels and 2) the use of wood for material substitution are considered. The GWP-based indicator leads to longer payback times, i.e. the time frame needed for the biomass option to be superior to its fossil-based alternative, than when just the cumulative balance of biogenic and fossil C stocks is considered. The warming payback time increases substantially with the residue diameter and low displacement factor (DF) of fossil C emissions. For the 35-cm stumps, the payback time appears to be more than 100 years in the climate conditions of Southern Finland when DF is lower than 0.5 in instant use and lower than 0.6 in continuous stump use. Wood use for construction appears to be more beneficial because, in addition to displaced emissions due to by-product bioenergy and material substitution, a significant part of round wood is sequestered into wood products for a long period, and even a zero payback time would be attainable with reasonable DFs.     

A pilot study for enhanced transformation of a metabolite 3,5-dichloroaniline derived from dicarboximide fungicides through immobilized laccase mediator system

Environmental Science and Pollution Research - This pilot investigation aimed to evaluate the removal efficiency and the underlying biocatalytic pathways of immobilized fungal laccase during the...     

The impact of size-segregated particle properties on daily mortality in Seoul,Korea

Environmental Science and Pollution Research - To investigate the causative component for certain health outcomes, the associations between the properties of ambient particles and cause-specific...     

Transformation of recovered cobalt from lithium-ion batteries into zeolitic imidazolate framework-67

Journal of Material Cycles and Waste Management - Electrical and electronic equipment with axillaries at their end of life are considered as e-waste. Utilization/reutilization of e-waste especially...