Analysis Of Pellets Research Articles

Effects of food deprivation state on feeding behavior and gastric evacuation of rock crabs, Cancer irroratus, during hypoxia

ABSTRACT Climate change and anthropological activities have led to an expansion of hypoxia into the natural habitat of Cancer irroratus. In this study, we examined the effects of hypoxia and food deprivation state on food intake and subsequent gastric processing. Three different techniques were used to measure food intake. The gravimetric analysis of dry food pellets was the most accurate method. In severe hypoxia (20% oxygen), rock crabs reduced food intake, and more crabs refused to eat. Compared with fasted crabs, more starved crabs tended to eat in severe hypoxia. Subsequently, prolonged gastric emptying times paralleled the previously measured postprandial oxygen consumption in hypoxia. Starved crabs also exhibited slightly longer transit times for digesta compared with fasted crabs. These results suggest that although a trade-off may occur in starved rock crabs between the need to procure nutrients and deal with hypoxic stress, impaired digestive processing may still deleteriously affect these animals.

The ranging, habitat selection, and foraging ecology of an endangered small desert mammal, the sandhill dunnartSminthopsis psammophila

AbstractThe conservation of threatened species often requires an examination of home range, foraging preferences, and diet. We used radio tracking, global positioning system data loggers, and fecal pellet analyses to study the nocturnal ecology of an endangered desert mammal, the sandhill dunnart, Sminthopsis psammophila. Twenty-four individuals were tracked between 2015 and 2018. The mean home range area of S. psammophila was 70 ha (100% minimum convex polygon). Reproductive males had a mean home range of 148 ha, whereas the ranges of all other groups were comparatively smaller. Sminthopsis psammophila preferred dense, long unburned foraging habitats. There was no effect of weather (excluding extreme cold/rain) on nocturnal ranging behavior. Ants comprised a significant proportion of the diet of S. psammophila and S. hirtipes, whereas S. dolichura consumed a broader range of prey. By integrating foraging and dietary analyses, we provide new insights to improve the conservation management of one of Australia’s least studied but most threatened marsupials.

Potential accident tolerant fuel candidate: Investigation of physical properties of the ternary phase U2CrN3

In the present study, physical properties of the ternary phase U2CrN3 are evaluated experimentally and by modeling methods. High density pellets containing the ternary phase were prepared by spark plasma sintering (SPS). The microstructural and crystallographic analyses of the composite pellets were performed using scanning electron microscopy (SEM), standardised energy dispersive spectroscopy (EDS) and electron backscatter diffraction (EBSD). Evaluation of the mechanical properties was performed by nanoindentation test. The impact of temperature on lattice properties was evaluated using high temperature X-ray diffraction (XRD) coupled with modeling. Progressive change in the lattice parameters was obtained from room temperature (RT) to 673 K, and the result was used to calculate average linear thermal expansion coefficients, as well as an input for the density functional theory (DFT) modeling to reassess the degradation of the mechanical properties. The ab-initio calculation provides an initial assessment of electronic configuration of this ternary phase in a direct comparison with one of UN phase. For this goal, modeling was also employed to evaluate point defect formation energies and electronic charge distribution in the ternary phase. Results indicate that the U2CrN3 phase has similar mechanical properties to UN (Young's, bulk, shear moduli, hardness). No preferential crystallographic orientation was observed in the composite pellet. However, charge electron density distribution highlights the significant directionality of chemical bonds, which is in agreement with the anisotropy and non-linear behaviour of the obtained thermal expansion (α¯(aa) = 9.12 × 10−6/K, α¯(ab) = 5.81 × 10−6/K and α¯(ac) = 6.08 × 10−6/K). As a consequence, uranium was found to be more strongly bound in the ternary structure which may delay diffusion and vacancy formation, promising an acceptable performance as nuclear fuel.

Co-combustion behavior, kinetic and ash melting characteristics analysis of clean coal and biomass pellet

In this study, the co-combustion characteristics and ash fusion temperatures of clean coal, biomass pellet and their blends were investigated by thermal analyzer and ash-melting point analyzer, respectively. Kinetic parameters were calculated by using the multistage reaction random pore model, which could be very consistent with the combustion law of the samples. The results show that the combustion characteristics of biomass pellet are better than those of clean coal, mainly influenced by the chemical structure. After mixing the two fuels, the flammability and comprehensive combustion performance were gradually improved, and there was an obvious synergistic effect. The best effect was when the biomass pellet mixing ratio was 60%. The increase of heating rate could promote synergy. The various activation energies of the solid carbon combustion stage decreased with the increase of biomass pellet ratio, and the change rule was similar to the synergistic effect. By detecting the shrinkage rate of ash and analyzing the phase composition and transformation, it is determined that the biomass blending ratio of 40–60% was most conducive to efficient utilization of the two fuels.

Diet and reproductive success of Great Horned Owl (<i>Bubo virginianus</i>) at its northern breeding limit

We studied the diet and reproductive success of Great Horned Owl (Bubo virginianus) at its northern range limit during an apparent high in the Snowshoe Hare (Lepus americanus) population. We performed diet analyses using images from fixed motion sensor cameras and pellet and prey remains collected at active nests, and gathered data on breeding success through camera and visual observations. Pellet data at 14 nests produced 1277 prey records consisting of 65–95% Snowshoe Hare biomass. Great Horned Owls ate 18 different prey types, with overall biomass consisting of 93% mammal, 7% bird, and less than 1% insects, frogs, and fish. The mean prey mass of 714 g (± 34 SE) was 2–25 times the mean prey mass of studies of this species at more southerly latitudes. Camera observations showed that Great Horned Owls delivered an average of 459 g/chick/d (± 75) throughout nesting. This was significantly (P = 0.005) higher than observations from Alberta, at 328–411 g/chick/d. Pellet/prey remains data showed that Great Horned Owls delivering a higher proportion of hares to their nestlings successfully raised more chicks (χ21 = 6.3, P = 0.012), highlighting the importance of this prey in the population dynamics of Great Horned Owl. In addition, we observed Snowshoe Hare removing pellets beneath nest sites, revealing an apparently undocumented bias to the use of pellet analysis.

Monitoring of Rabbit Hemorrhagic Disease Virus in European Wild Rabbit (Oryctolagus cuniculus) Populations by PCR Analysis of Rabbit Fecal Pellets.

European rabbits (Oryctolagus cuniculus) are affected by rabbit hemorrhagic disease (RHD), which is caused by a lagovirus responsible for significant mortality in European wild rabbit populations. Our study aimed to evaluate the potential for detecting viral RNA by duplex real-time PCR in rabbit fecal pellets collected in the field, as a noninvasive method to monitor RHD virus circulation in wild populations. To do this, monthly discoveries of rabbits that died from RHD and detection of viral RNA in fecal pellets were recorded in two enclosed populations of wild rabbits throughout a year. The results suggested a low performance of this procedure to monitor viral infection incidence and a weak concordance with monthly discoveries of rabbits that died from RHD. This poor association was probably due to the low amount of viral RNA in feces, the prolonged time of excretion after infection, and that the number of rabbits found dead from RHD does not necessarily correlate with RHD incidence. Nevertheless, this procedure may be a complementary noninvasive method to assist in determining the presence of RHD viruses in populations. Additional research is needed to determine the suitability of this methodology to perform epidemiologic surveys on wild populations of European rabbits and, especially, other European or North American lagomorph species affected by lagoviruses.

Synthesis and Characterization of Gadolinium-Doped Zirconia as a Potential Electrolyte for Solid Oxide Fuel Cells

Zirconia-based composites with high thermochemical stability and electrochemical activity are the most promising solid electrolytes for manufacturing solid oxide fuel cells (SOFCs). In the present work, nanocrystalline composite powders of gadolinium-doped zirconia (GDZ: Gd2xZr2(1−x)O4−x) with various doping fractions (0.01 ≤ x ≤ 0.16) were synthesized by the Pechini method and applied for the fabrication of several electrolyte pellets to evaluate their physicochemical properties, sinterability, and conductivity. The X-ray diffraction (XRD) patterns and the thermogravimetry/differential thermal analysis (TGA/DTA) of the synthesized powders confirmed the successful formation of nanocrystalline GDZ in the tetragonal phase with complete substitution of gadolinium phase into the zirconia (ZrO2) lattice. The synthesized gadolinium zirconate powders were then shaped into pellet forms using the tape casting method, followed by sintering at 1300 °C (for 2.5 h). The microstructural analysis of the electrolyte pellets showed suitable grain boundary welding at the surface with an acceptable grain growth at the bulk of the T-phase GDZ samples. The impedance measurements indicated that the T-phase GDZ-8 could provide a comparably higher ionic conductivity (with 7.23 × 10−2 S/cm in the air at 800 °C) than the other dopant fractions. The results of this work can help better understand the characteristics and electrochemical performance of the T-phase gadolinium zirconate as a potential electrolyte for the fabrication of SOFCs.

Atomic Defect Mediated Li-Ion Diffusion in a Lithium Lanthanum Titanate Solid-State Electrolyte.

Lithium lanthanum titanium oxide (LLTO) as a fast Li-ion conductor is a promising candidate for future all-solid-state Li batteries. Fundamental understanding of the microstructure of LLTO and its effect on the Li+ diffusion mechanism, especially across different length scales and interfaces, is a prerequisite to improving the material design and processing development of oxide-based solid electrolytes. Herein, through detailed structural analysis of LLTO ceramic pellets by aberration-corrected transmission electron microscopy, we discovered previously unreported intrinsic planar defects in LLTO single-crystal grains. These planar defects feature an antiphase boundary along specific crystal planes with a "rock-salt" structure enriched by Li within a few atomic layers. Corroborated by density-functional-theory-based calculations, we show an increased diffusion barrier across these planar defects inevitably lowers the bulk Li+ diffusivity of the oxide electrolyte.

Analyses of Pellets Produced from Spruce Sawdust, Spruce Bark, and Pine Cones in Different Proportions

A lot of residual biomass has energy value and can be used for further applications through suitable treatments, such as pelletization. This treatment can improve properties, mainly energy density, but can also lead to problems due to their low ash melting temperatures, high ash content, and the formation of harmful compounds during combustion. This article deals with the energy potential of pellets produced from spruce sawdust, spruce bark, and pine cones in different proportions. The impact of cone and bark contents on pellet properties was also observed. The energy properties of the produced pellets were measured, such as the contents of carbon, hydrogen, nitrogen, moisture, volatile, fixed carbon, and ash, as well as calorific values and ash melting temperatures. Based on the results, it can be concluded that the addition of pine cones and spruce bark to spruce sawdust mainly affected the contents of nitrogen and ash and melting temperatures. Despite this, all produced pellets met the standard EN ISO 17225-2 for the content of nitrogen, ash, and also lower calorific value at least B quality. However, only three pellet samples of five met this standard for A2 and B quality for ash melting behavior. Therefore, they present an alternative fuel with interesting energy potential.

Exosomes are secreted at similar densities by M21 and PC3 human cancer cells and show paclitaxel solubility.

Exosomes are cell-secreted vesicles less than ≈150nm in size that contain gene-encoding and gene-silencing RNA and cytosolic proteins with roles in intercellular communication. Interest in the use of exosomes as targeted drug delivery vehicles has grown since it was shown that they can bind specific cells and deliver intact genetic material to the cytosol of target cells. We isolated extracellular vesicles (EVs), consisting of a mixture of exosomes and microvesicles, from prostate (PC3) and melanoma (M21) cancer cell lines using serial ultracentrifugation. Interrogation via western blot analysis confirmed enrichment of CD63, a widely recognized EV surface protein, in the EV pellet from both cell lines. Nanoparticle tracking analysis (NTA) of EV pellets revealed that the two cell lines produced distinct vesicle size profiles in the ≈30nm to ≈400nm range. NTA further showed that the fraction of exosomes to all EVs was constant, suggesting cellular mechanisms that control the fraction of secreted vesicles that are exosomes. Transmission electron microscopy (TEM) images of the unmodified PC3 EVs showed vesicles with cup-like (i.e., nanocapsule) and previously unreported prolate morphologies. The observed non-spherical morphologies for dehydrated exosomal vesicles (size ≈30-100nm) are most likely related to the dense packing of proteins in exosome membranes. Solubility phase diagram data showed that EVs enhanced the solubility of paclitaxel (PTX) in aqueous solution compared to a water-only control. Combined with their inherent targeting and cytosol delivery properties, these findings highlight the potential advantages of using exosomes as chemotherapeutic drug carriers in vivo.

More than just meat: Carcass decomposition shapes trophic identities in a terrestrial vertebrate

Abstract Most food web models fail to account for the full complexity of interactions within a community, particularly where microbes are involved. Carcasses are microbe‐rich resources and may represent a common nexus for the macrobiome and microbiome, effectively uniting autotrophs, consumers, predators and microbiota. We evaluated the role of carcasses as multitrophic resources and explored dietary partitioning for a sexually dimorphic obligate scavenger known for its hierarchical social system. This study was set in a well‐studied community of camelids Vicugna, Lama guanicoe, pumas Puma concolor and Andean condors Vultur gryphus in the Andes. We hypothesized that condors, by feeding on trophically distinct dietary substrates within any given carcass, would have highly variable trophic position (TP) values. Furthermore, we expected that the microbial consumers within the carcass would inflate TP values in both, the carrion and the condors. Thus, we expected that the trophic heterogeneity within a carcass could facilitate sex‐based dietary partitioning in condors. We used a multifaceted approach to assess the foraging of Andean condors, using regurgitated pellet and bulk isotopic analyses, and also quantified the TP of the entire community of graminoids, camelids, camelid carrion, pumas, and female and male condors employing compound‐specific stable isotopes analysis of amino acids. Our analysis of condor pellets and bulk isotopes revealed non‐trivial plant consumption, close to 10% of condor diet. Isotope analysis of amino acids revealed that condors had highly variable TPs (2.9 ± 0.3) compared to pumas (3.0 ± 0.0) and camelids (2.0 ± 0.1), likely representing ‘trophic omnivory’, wherein the condors consume plants (TP = 1.0 ± 0.1) and microbe‐colonized carrion (2.3 ± 0.1). Female condors exhibited a TP (2.8 ± 0.2) lower than strict carnivory, suggesting that they consume more plant biomass in a carcass, while males (TP = 3.1 ± 0.3) are likely consuming more of the microbe‐rich animal tissue. Our study highlights that carcasses represent a trophically heterogeneous resource and that vertebrate scavengers can feed across trophic groups within the carcass, from autotrophs to secondary consumers, and from both the macrobiome and microbiome. Thus, integration of microbes in macroecological contexts can help to resolve trophic identity, and better characterize the importance of microbes in detritivorous and omnivorous species. Read the free Plain Language Summary for this article on the Journal blog.

Are little brown bats (Myotis lucifugus) impacted by dietary exposure to microcystin?✰

The cyanobacterium, Microcystis aeruginosa, can produce the hepatotoxin microcystin. When toxic M. aeruginosa overwinters in the sediments of lakes, it may be ingested by aquatic insects and bioaccumulate in nymphs of Hexagenia mayflies. When volant Hexagenia emerge from lakes to reproduce, they provide an abundant, albeit temporary, food source for many terrestrial organisms including bats. Little brown bats, Myotis lucifugus, feed opportunistically on aquatic insects including Hexagenia. To determine if microcystin moves from aquatic to terrestrial ecosystems via trophic transfer, we combined a dietary analysis with the quantification of microcystin in bat livers and feces. In June 2014, coincident with the local Hexagenia emergence, bat feces were collected from underneath a maternity roost near Little Traverse Lake (Leelanau County, Michigan, USA). Insects in the diet were identified via molecular analyses of fecal pellets from the roost and from individual bats. Livers and feces were collected from 19 female M. lucifugus, and the concentrations of microcystin in these liver tissues and feces were measured using an enzyme-linked immunosorbent assay (ELISA) and liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS). We show that the majority of the bats’ diets consisted of aquatic insects and that microcystin was detected in high concentrations (up to 129.9 μg/kg dw) in the bat feces by ELISA. Histopathological examination of three bat livers with the highest concentrations of microcystin showed no evidence of phycotoxicosis, indicating that M. lucifugus may not be immediately affected by the ingestion of microcystin. Future work could examine whether bats suffer delayed physiological effects from ingestion of microcystin.

Методи обліку чисельності гризунів

This is a republication of the methodological review originally published in 1957, which has been important for the organization of local and regional studies of the mammal fauna, particularly in the identification of species composition and estimates of the relative abundance of small (mouse-like) rodents. The present publication is accompanied by an editorial foreword and contains seven chapters. The first three are titled ‘Rodents as objects of census and monitoring,’ ‘Census of rodents and its components,’ and ‘Census of rodents in the field with attention to relative and absolute census.’ The section on relative census includes such topics as ‘Census by biological indicators,’ ‘Census by analysis of pellets and excrements of predators of mice,’ ‘Census by counting burrows (holes),’ and ‘Cenus on trap lines.’ The section on absolute census includes parts such as ‘Census by complete excavation of burrows and complete capture of their population’ and ‘Census of rodents in various kinds of haystack.’ The other sections are ‘Census of forest-dwelling rodents,’ ‘Census of rats and mice in human settlements’ (includes three parts: the method of dusty areas, the method of trial bait, and the method of almost complete capture), ‘Methods of combating certain species of harmful rodents’ (abridged), ‘Controlling methods of some species of harmful rodents’ (abridged), and ‘Collection and transfer to specialists of rodent materials for scientific purposes.’

Developing methodology for petrographic analysis of solid biomass in reflected light

As concerns about climate change and sustainability rise, biomass utilization has a potential to become one of the pillars of the future energy market. It is therefore critical to assure that solid biomass fuels are of the highest quality and do not contribute to avoidable air pollution. Our research has shown that petrographic analysis of solid biomass in reflected light can quickly and reliably provide information on fuel composition and contamination. As such, this technique has a potential to improve our understanding of raw fuel properties and, in some instances, even predict parameters of their combustion emissions.This paper provides guidelines for conducting microscopic analysis of wood pellets and charcoal-based fuels in reflected light. It presents two preliminary microscopic classifications of solid biomass components and emphasizes the need for training materials, exemplified by recently published photomicrograph atlases. Our research indicates that pairing reflected light microscopy with the currently used standard testing would enhance the quality assessment of solid biomass. To achieve this, the methodology must be promoted, tested for interlaboratory reproducibility, and finally standardized.

PROPOZYCJA MONITORINGU NORNICY RUDEJ (MYODES GLAREOLU, SCHREBER 1780)

There are many reasons why it might be necessary to monitor the bank voles. It causes damage to trees and eats seeds in orchards and tree plantations, and the determination of its presence as well as the effectiveness of the measures taken to minimize losses is very important in the activity of the above-mentioned. The rodent is also the main for central Europe reservoir of the Puumala virus, which is dangerous to humans, so observing the trends in the number of voles may be crucial. The small number of the species may indicate environmental poisoning, especially with copper. And finally, it is a very important species for the environment, both transformed by man and natural, so it is very important to preserve it despite the climate changes. The bank vole is a small mammal from the Cricetidae family. It occurs all over Europe. It lives mainly in deciduous forests of medium density and rich undergrowth, although it is also found in other areas, including anthropogenic ones. The proposed monitoring is based on catching with the use of wooden box traps and the analysis of pellets. The indicators used would be: the number of individuals caught per 100 trap-nights, the percentage of the species in total number of small mammals and the age structure of the population. In the first method one should remember about practices that will reduce or eliminate the mortality of captured animals – the appropriate setting of traps and selection of weather conditions. Also collecting pellets, one should bear in mind the limitations of this method and the differences between the spring-summer and autumn-winter material. The determination of the condition of the habitat may be based on the percentage of deciduous trees, density of trees and the appearance of the undergrowth.

Diets of Black Vultures and Turkey Vultures in Coastal South Carolina, USA with a Review of Species' Dietary Information

Food availability resulting from anthropogenic land-use changes may have contributed to the recent increase of Cathartes aura (Turkey Vulture) and Coragyps atratus (Black Vulture) populations. We assessed anthropogenic contributions to diets of these species by analyzing 176 pellets collected from communal roosts in coastal South Carolina. To provide further insight into diets, we conducted a literature review of pellet-based studies for both species. Our pellet analyses demonstrated consumption of 12 mammal species with Odocoileus virginianus (White-tailed Deer) as the primary food item, present in 65% of samples and constituting 35% average percent volume in pellets. Mephitis mephitis (Striped Skunk) and Procyon lotor (Raccoon) were also commonly consumed. Presence of anthropogenic items in 47% of pellets indicated substantial garbage consumption. Our review consisted of 14 studies and revealed wide variability in diet across study sites, with large mammals (>15 kg) typically comprising the majority of species consumed. We suggest that increasing deer populations provide an important source of carrion for vultures in this area and likely throughout eastern North America. Ungulate populations, roadkill, and garbage appear to contribute considerably to Turkey Vulture and Black Vulture diets. As such, mitigation of human–vulture conflict will require effective garbage and roadkill management as Turkey Vulture and Black Vulture populations increasingly expand.

Pellet analysis evidences flexibility in the diet of Brown Skua (Stercorarius antarcticus) during breeding at Esperanza/Hope Bay (Antarctic Peninsula)

Pellet analysis evidences flexibility in the diet of Brown Skua (Stercorarius antarcticus) during breeding at Esperanza/Hope Bay (Antarctic Peninsula)

Enhancement of polysaccharides production using microparticle enhanced technology by Paraisaria dubia

BackgroundPolysaccharides are important active ingredients in Ophiocordyceps gracilis with many physiological functions. It can be obtained from the submerged fermentation by the anamorph (Paraisaria dubia) of Ophiocordyceps gracilis. However, it was found that the mycelial pellets of Paraisaria dubia were dense and increased in volume in the process of fermentation, and the center of the pellets was autolysis due to the lack of nutrient delivery, which extremely reduced the yield of polysaccharides. Therefore, it is necessary to excavate a fermentation strategy based on morphological regulation for Paraisaria dubia to promote polysaccharides accumulation.ResultsIn this study, we developed a method for enhancing polysaccharides production by Paraisaria dubia using microparticle enhanced technology, talc microparticle as morphological inducer, and investigated the enhancement mechanisms by transcriptomics. The optimal size and dose of talc were found to be 2000 mesh and 15 g/L, which resulted in a high polysaccharides yield. It was found that the efficient synthesis of polysaccharides requires an appropriate mycelial morphology through morphological analysis of mycelial pellets. And, the polysaccharides synthesis was found to mainly rely on the ABC transporter-dependent pathway revealed by transcriptomics. This method was also showed excellent robustness in 5-L bioreactor, the maximum yields of intracellular polysaccharide and exopolysaccharides were 83.23 ± 1.4 and 518.50 ± 4.1 mg/L, respectively. And, the fermented polysaccharides were stable and showed excellent biological activity.ConclusionsThis study provides a feasible strategy for the efficient preparation of cordyceps polysaccharides via submerged fermentation with talc microparticles, which may also be applicable to similar macrofungi.Graphical

Phase equilibria analysis of hematite pellets during induration

In order to study the change of each phase and the influence of single oxide during the consolidation of pellets. A systematic thermodynamic calculation was carried out through the phase diagram to study the influence of five oxides (CaO, SiO2, Fe2O3, Al2O3 and MgO) on the phase equilibrium of the hematite pellet system. The results show that the content of CaO has the most significant effect on the content of liquid phase and SPINA. There are critical values for the influence of SiO2 and CaO on the Ca3Fe2Si3O12 phase, which are 3.5% and 3.0%, respectively. Through in-situ heating experiments, XRD-Rietveld and SEM-EDS, the macro morphology and phase composition of the hardened samples were compared and analyzed. Finally, a multiple regression model is used to predict the liquid content of hematite pellets, which is effective in predicting the phase component.

Emission characteristics from the combustion of Acacia Mangium in the automatic feeding pellet stove

The study provides new insights on the empirical facts and figures of Acacia Mangium graded wood pellets in non-industrial thermochemical applications. The test material was characterized according to normative solid biofuel specifications that confirmed a relevant net calorific value, a considerable mass fraction of the ash content, and the sign of ash softening initially observed at a notable temperature. The instrument readings of six major combustion gaseous components and particulate matter in the exhaust gas verified consistent emission profiles of woody solid biofuels in small-scale combustion installations. The calculated values of CO, CO2, NO, SO2, TOC and PM were analyzed in depth. The emission characteristics obtained revealed the apparent correlations of the fractions of gaseous components subjected to the elemental content determined by the ultimate analysis of Acacia Mangium wood pellets. The particulate matter emitted containing unburnt carbonaceous solid residues and inorganic materials remaining as byproducts were comparatively evaluated according to the different fuel types and variable test devices in earlier works. The mechanism of production and removal of volatilized alkali metals that influence solid particle formation was discussed. The excessive amount of ash-forming elements could potentially cause uncertain fluctuations in emission characteristics, which were remarked upon by further ash-related investigations requiring additional analysis.