Foundation Bearing Research Articles

Scour effects on the bearing capacity of multi-bucket jacket foundation for offshore wind turbines

The Multi-Bucket Jacket Foundation (MBJF) is presently being installed in Chinese wind farms with increasing numbers. Compared to monopiles, MBJF is a shallow foundation and the effect of scouring on the bearing capacity is more significant. This research proposes a universal three-dimensional model of the MBJF with local scour to efficiently estimate the effect of scouring on the MBJF bearing capacity. Firstly, using the proposed model, the ultimate bearing capacity is calculated under a single load, and the discounting effect of different scour ranges and scour depths on the ultimate bearing capacity is evaluated. Furthermore, the fixed load-displacement approach is used to calculate the failure envelope of the foundation under composite loading mode, and the influence of different scour patterns on the failure envelope is compared. The findings reveal that when the scour extent and depth increase, the foundation's bearing capacity decreases non-linearly, and the foundation bearing envelope line gradually shrinks. Under the condition that the ultimate vertical load is not exceeded, a rise in vertical load can enhance the ultimate load capacity after scouring to a certain extent. Finally, the calculated envelopes are integrated with engineering applications to quantify the safety redundancy of the MBJF bearing capacity for different seabed morphologies. The method and results can provide methodological support for the accurate prediction and efficient assessment of the MBJF's post-scour bearing capacity.

Bubbled roller-compacted concrete dam: an idea of a hollow dam

Roller-compacted concrete (RCC) is widely known for its relatively low cost and short construction time. RCC gravity dams require high foundation (rock) bearing capacity. Research studies have been carried out which propose to rationalise the amount of material in the dam by creating inner voids, in the shape of bubbles. As a key requirement, the introduced bubbles should not affect the dam stability and safety. The bubbles will reduce the self-weight of the dam and minimise the required rock-bearing capacity. A system of pipes connecting the bubbles ensures drainage of the bubbles. The proposed dam would save about 12% of the required concrete volume. Different construction methods were studied and the best alternative is the use of precast hollow boxes. This decreases RCC placement in the dam by 32.5%. The objective is to speed the construction process and minimise the risk of the heat of hydration.

Numerical analysis on load-settlement response of reinforced granular blanket over ordinary stone column

Stone columns are a more economical and efficient method to enhance the strength of expansive soils. Using a granular blanket over the top of the ordinary stone columns (OSC) improves the drainage and distribution of the applied stress impending from the superstructure. The present study studied the effect of geogrid layers in a granular blanket (GB) over the top of the OSC numerically using 'PLAXIS 2D'. 'Mohr-Coulomb failure criterion was deliberated for the stone column, granular blanket, expansive soil, and elastoplastic behavior is considered for geogrid layers as reinforcement. Present review results are validated with the experimental results and agree greatly. Numerical results show that the construction of a GB with a geogrid layer over the stone column increases stress transformation to the depth of OSC. Thus 'stress concentration' is decreased in the higher zone of the OSC. Likewise, assessing the impact of geogrid layers in a granular blanket on the 'bearing capacity and settlement of OSC, it was observed that it reduces the lateral bulging, settlement and increases the ground's bearing capacity.

The Impact of Train Operation Time with Ground Borne Vibration Induced by Railway Traffic

Ground-borne vibration caused by rail transport has detrimental effects on residential areas along the railway tracks. The residents who are subjected to daily ground-borne vibration may also experience more severe health issues over the long term. This involves the mental well-being of the people who live nearby. The efficiency and quality of life of residents may also theoretically be impaired by direct exposure to ground-borne vibration caused by trains. As the government decided to invest further in public infrastructure, especially in the railway transport system, the railway transport system in Malaysia is changing to a higher level. Complaints about human discomfort and irritation caused by the ground-borne vibrations created by rail transport have been reported to increase as a result of the expansion of coverage for rail transport. Many previous studies have investigated the influence of different parameter variables on ground-borne vibrations. The ground-borne vibrations are considered as the dependent variable by some of the inquiries, and the other parameters are classified as independent variables. However, depending on the nature and source of the study performed, the results of the independent variables will differ from the researchers. This analysis aims to examine one of the variables which is the train operating hour in terms of peak and non-peak hours against the ground-borne vibrations caused by the train using local conditions.

MIXED EVIDENCE FOR NICHE CONSERVATISM IN MOUNTAIN BEAVER (APLODONTIA RUFA) LINEAGES

Range shifts in response to past climatic changes have been documented in a variety of species and have often resulted in the isolation of relict populations. Understanding how these isolated populations develop local adaptations or maintain their historic climatic niche is crucial to creating effective management plans in the face of current climate change. While Mountain Beavers (Aplodontia rufa) have endured through major climatic shifts in the past, they maintain physiological constraints that limit their distribution to cool, humid climates. Increasing temperatures since the last glacial maximum likely had a strong influence in reducing their range. The species now persists as 5 genetically distinct clades, but it is not clear to what extent climatic differences have driven genetic isolation compared to other factors like topography. We compared species-distribution models (SDMs) for the 5 clades of Mountain Beaver to understand whether this species tends towards niche conservatism or adapts to local climates. Presence points from the Global Biodiversity Information Facility were divided into clades and combined with climatic layers from BioClim to develop SDMs for each clade. Niche overlap was then compared to genetic relatedness between all pairings of clades. High temperatures were a limiting factor in distribution for all clades and, despite a low level of niche overlap at broad scales, Mountain Beavers appeared to display some level of niche conservatism. These landscape level SDMs showed that some clades do exist in a warmer climate than other Mountain Beavers; however, fine-scale models for the Point Arena subspecies suggested they persist by selecting the coolest places within that range. This suggests that niche overlap between clades may be higher than what is detected at the coarser scale. Further research is needed to understand the mechanisms limiting the distribution of these subspecies.

DIET COMPOSITON OF FISHERS (PEKANIA PENNANTI) REINTRODUCED ON THE OLYMPIC PENINSULA, WASHINGTON

Knowledge of diet composition can inform management strategies and efforts to recover endangered carnivore populations in vacant portions of their historic ranges. One such species, the Fisher (Pekania pennanti), was extirpated in Washington State prior to any formal documentation of its food habits in the coastal coniferous forests of western Washington. Fisher recovery efforts in Washington, based on translocating Fishers from extant populations, have been ongoing since 2008, beginning with the release of 90 Fishers on Washington's Olympic Peninsula from 2008 to 2010. We collected fecal samples or digestive tracts from 13 Fishers opportunistically on the Olympic Peninsula from 2009 through 2013. Subsequently, we identified the species composition of each sample's contents to determine the primary foods consumed by the reintroduced Fishers. Fisher diets were diverse and dominated by mammalian prey. Contents of feces and digestive tracts of Fishers were composed primarily of Snowshoe Hare (Lepus americanus) remains, followed by lesser proportions of Mountain Beavers (Aplodontia rufa), Northern Flying Squirrels (Glaucomys sabrinus), Douglas Squirrels (Tamiasciurus douglasii), Southern Red-backed Voles (Myodes gapperi), shrews (Sorex spp.), and unidentified ungulate species. The diet of Fishers comprised species that occur across a wide range of land uses and management prescriptions, including previously logged forests and mature forests that have been set aside for retention of old-growth forest characteristics. Additional study of prey abundance and Fisher foraging behaviors related to structural habitat characteristics across a gradient of land uses would provide useful insights for enhancing the effectiveness of conservation efforts to benefit Fishers in Pacific Northwest coastal forests.

Simplified parametric modeling to predict vibration attenuation provided by on-grade slabs

When measured vibration amplitudes at the proposed site for a highly sensitive facility exceed the maximum allowable for the sensitive equipment, mitigation measures must be integrated into the design that will reduce the vibration amplitudes to meet the requirements. Past studies have shown that thick concrete slabs supported on a well-engineered subgrade can effectively reduce ground borne vibrations at certain frequencies. Predicting the vibration performance of a new slab-on-grade can be a significant challenge, however, as the performance is highly dependent upon the site soil conditions and nature of the vibration sources impacting the location, as well as structural characteristics. Large and detailed three-dimensional finite element analysis models of the site conditions and proposed structure are often used for this type of assessment, however development of such a model requires significant time and cost to develop accurately. This presentation discusses a proposed an alternative simplified parametric modeling technique using two-dimensional plane strain modeling. This technique can be utilized in combination with real-world data to predict the relative benefit of various slab thicknesses and design features such as structural breaks. The paper will include multiple comparisons between predicted results using this methodology and field measurement results.

The effect of two trains passing at the same time on the ground borne vibration level

When predicting the ground borne vibration level, it is assumed that only one train passes so the predicted vibration level is caused by a single train. When there is one track for every direction of the train, it is possible that two trains will pass each other on a specific location at the same time. What influence do these two trains have on the vibration level compared to the vibration level of a single train passing that same location? For this study ground borne vibration levels have been measured on two locations in The Netherlands using a 3 by 3 grid, 25 meters apart, on a distance of 25, 50 and 75 meters of the track. During the 4 weeks measuring time, all the trains have been captured on video. All the double train situations have been marked. The corresponding vibration level Vmax (according to the Dutch SBR B guideline) has been determined for both the single trains and the double trains and compared to each other. In the analysis, the type of trains passing each other and the distance of the receiver to the track, has been taken into account when determining the difference in vibration level.

Complete mitochondrial genome of the giant root-rat (Tachyoryctes macrocephalus)

The endangered giant root-rat (Tachyoryctes macrocephalus, also known as giant mole rat) is a fossorial rodent endemic to the afro-alpine grasslands of the Bale Mountains in Ethiopia. The species is an important ecosystem engineer with the majority of the global population found within 1000 km2. Here, we present the first complete mitochondrial genome of the giant root-rat and the genus Tachyoryctes, recovered using shotgun sequencing and iterative mapping. A phylogenetic analysis including 15 other representatives of the family Spalacidae placed Tachyoryctes as sister genus to Rhizomys with high support. This position is in accordance with a recent study revealing the topology of the Spalacidae family. The full mitochondrial genome of the giant root-rat presents an important resource for further population genetic studies.

Implementation of Combined Loading to Calculate Ground Bearing Pressure under Crawler Crane Tracks

AbstractModular projects in the construction industry employ high-capacity crawler cranes. Due to the significant increase in the weights of modules in recent years, ensuring the integrity of groun...

Formation and evolution of suprapermafrost taliks beneath earth-filled embankments along the Qinghai-Tibet Railway in permafrost regions

Taliks are bodies or layers of unfrozen ground in permafrost areas. Suprapermafrost taliks (SPTs) formed between the active layer and permafrost table beneath embankments along the Qinghai-Tibet Railway (QTR) would reduce the stability of the embankments and thus threaten the safety of QTR operations, because the SPTs exhibit a lower bearing capacity than that of frozen ground. This study investigated the formation and evolution of SPTs beneath earth-filled embankments at two monitoring sites (P7 and P17) along the QTR in order to determine the SPTs formation mechanism. The SPTs under the left shoulder of the embankments at P7 and P17 were caused by thermal disturbance of filling and vertical heat accumulation, respectively. The mechanism of SPTs formation beneath the embankments was closely associated with the mean annual ground temperature and the height of embankment filling materials. The study findings can facilitate understanding the formation and evolution of SPTs beneath the embankments in similar sections along the QTR. In particular, the findings can serve as a guidance for the QTR administration bureau in implementing countermeasures for eliminating these unfrozen layers and increasing ground bearing capacity.

Diverse Genotypes and Species of Cryptosporidium in Wild Rodent Species from the West Coast of the USA and Implications for Raw Produce Safety and Microbial Water Quality.

Cryptosporidium spp. are protozoan parasites that infect perhaps all vertebrate animals, with a subset of species and genotypes that function as food- and waterborne pathogens. The objective of this work was to collate the Cryptosporidium species and genotypes from common wild rodents on the west coast of the USA and update the information regarding the zoonotic potential of Cryptosporidium from these ubiquitous wild species. Representative sequences of the 18S rRNA gene for a unique set of Cryptosporidium isolates obtained from deer mice, house mice, mountain beavers, yellow-bellied marmot, long-tailed vole, California ground squirrels, Belding’s ground squirrels, and a golden-mantled ground squirrel in GenBank were selected for phylogenetic analysis. Phylogenetic and BLAST analysis indicated that 4 (18%) of the 22 unique Cryptosporidium sequences from these wild rodent species were 99.75% to 100% identical to known zoonotic species (C. parvum, C. ubiquitum, C. xiaoi), suggesting that a minority of these representative Cryptosporidium isolates could have a public health impact through food and waterborne routes of human exposure. These zoonotic isolates were shed by deer mice and a yellow-bellied marmot from California, and from a mountain beaver trapped in Oregon. In addition, the group of unique Cryptosporidium isolates from deer mice and ground dwelling squirrels exhibited considerable DNA diversity, with multiple isolates appearing to be either host-limited or distributed throughout the various clades within the phylogenetic tree representing the various Cryptosporidium species from host mammals. These results indicate that only a subset of the unique Cryptosporidium genotypes and species obtained from wild rodents on the US west coast are of public health concern; nevertheless, given the geographic ubiquity of many of these host species and often high density at critical locations like municipal watersheds or produce production fields, prudent pest control practices are warranted to minimize the risks of water- and foodborne transmission to humans.

Reducing ground borne noise due to railways: A practical application

The construction of new buildings very close to existing tracks, with heavy commuting traffic, requires careful design. Such projects must be accompanied with noise and vibration reduction measures. The practical case here considered has been analysed by first assessing the existing situation prior to construction (type of soil and traffic). In a second stage, we have proposed and quantified solutions to reduce vibration and ground-borne noise levels inside the buildings. A 2.5D FEM/BEM commercial software (Mefissto), developed by CSTB, has been employed in what is a very challenging numerical context: multi-layered ground, large multi-levels buildings, large frequency range (10–250 Hz). In every situation, the use of an original 2.75D approach leads to the low frequency noise levels inside the buildings. As the trackwork cannot, in this case, be modified the solutions tested consist in inserting different types of barriers in the ground or in inserting either spring of resilient bearings (decoupling) in the lower part of the structure. Results are compared to target values in terms of vibration and ground-borne noise levels selected in order to limit dwellings occupants’ annoyance. Satisfactory results can only be achieved with the use of the decoupling solution.

EVALUASI STABILITAS DINDING PENAHAN TANAH TIPE KANTILEVER DI DESA NGROTO, KECAMATAN PUJON, KABUPATEN MALANG

AbstractWavy topographical conditions with high rainfall intensity cause cantilever type retaining wall on Jalan Brigjen Abdul Manan Wijaya in Ngroto village, Pujon District, Malang Regency, which borders the Konto River avalanche. The stability of the retaining wall can be expressed as Fs (Savety Factor). Factor value the security that is reviewed is the Fs bolster, namely the safety factor against the overthrowing force, the Fs shear is the safety factor against the shear force at the base of the retaining wall, Fs, the bearing capacity of the soil is a factor safety of soil bearing capacity. The purpose of this evaluation is to determine the wall planning cantilever type retaining wall and evaluate the stability of cantilever type retaining wall against the dangers of rolling, shearing, soil bearing capacity and knowing the budget plan for wall planning Cantilever type retaining wall. The result of this evaluation shows the cantilever retaining wall with dimensions H = 7, B = 3.5 Ta = 0.5 Tb = 0.7 D = 1 declared safe with the safety value for normal water level fs slide 1.8> 1.5 (safe), fs roll 2> 1.5 (safe), fs ground bearing capacity 186.8> 4752.86 (safe). Water face flood fs shear 2,6> 1,5 (safe) fs rolling 2,3> 1,5 (safe) fs soil bearing capacity 186.8> 4752.86 (safe). The total cost required for the construction of a cantilever type retaining wall of length 20 m T = 7 width 3.5 m for Rp. 290,570,000.Keywords: Retaining walls, Dimensions, Stability of retaining walls

Evaluating the effects of mountain beaver (Aplodontia rufa) management on conifer stocking in western Oregon

Mountain beaver (Aplodontia rufa) is the most primitive rodent species in North America and is endemic to the Pacific Northwest, USA. Within their range, mountain beaver cause more conflict with conifer forest regeneration than any other vertebrate species. Most damage occurs as a result of clipping and browsing new seedlings, which reduces stocking density and delays stand development. An integrated approach using trapping and a registered toxicant (baiting) has been suggested as the most efficacious means to reduce seedling loss during stand initiation. We evaluated this management strategy in intensively managed conifer stands across two mountain ranges in western Oregon. Harvest units were divided equally and management (trapping and baiting) was implemented on a randomly selected half of each unit; the remaining halves served as an experimental control. We conducted damage assessments in fixed 0.04 ha circular plots at approximate 1, 6, and 12 month intervals after planting and initiation of management activities. After 12 months, we observed mountain beaver damage in 100% of control plots and 95% of treatment plots; however, there was a 79% decrease in the estimated odds of damage for plots where trapping and baiting was implemented (95% CI 43–92). Mean seedling height was 10.6 cm taller in treated plots than control plots 1 year post-planting (95% CI 4.1–17.1). Reoccupation of vacant burrows began within 1 month; within 12 months, only 5% of trapped plots remained unoccupied. Reported costs and benefits varied among harvest units, but management was less expensive ($154.09/ha) than the cost of interplanting gaps created by mountain beaver damage ($182.13/ha). Although trapping and baiting may not offer a one-time solution to damage problems, it is an effective tool in reducing damage, saving management costs, and meeting compliance with forest regulations and certification requirements.

Literarische Fürsprache bei Franz Kafka: Rhetorik und Poetik by Doreen Densky

Reviewed by: Literarische Fürsprache bei Franz Kafka: Rhetorik und Poetik by Doreen Densky Aaron Carpenter Doreen Densky, Literarische Fürsprache bei Franz Kafka: Rhetorik und Poetik. Berlin: De Gruyter. 2020. 230 pp. Doreen Densky's book Literarische Fürsprache bei Franz Kafka: Rhetorik und Poetik is an excellent analysis of Franz Kafka's use of the advocate and advocacy (Fürsprache) to speak for and to various groups in his literary works, to his legal professor, and in everyday life. Kafka's life as an advocate started with his work as a trained lawyer working at an insurance firm, progressed through his speaking for Yiddish theater, and ended with his speaking for animals [End Page 135] near the end of his life. Denksy offers a detailed analysis of how Kafka diminished the role of the advocate over the course of his three novels, while leaving open the possibility of advocating for others through his own writing. Densky begins by examining Kafka's advocacy work in his job as a lawyer. She notes that he would approve documents with his initials, rather than a signature, as was common (64). This returns in the protagonist Josef K.'s abbreviated last name in Der Proceß, which, as Densky argues, also makes him into a representative of the everyman (113). This removal of identity is even more pronounced in Das Schloß, in which the protagonist is reduced to a single letter: K. Kafka also served as an advocate for Yitzhak Löwy and the Yiddish theater, both by giving a speech on the Yiddish language at a fundraiser and by helping Löwy and the troupe find financial assistance. Densky argues that Kafka acted as an editor of Jewish literature and poetry in his speech, but that it could only work, "weil er die Richter ausblendet, die überzeugt werden sollen und weil er sich von Löwy zum Redezeitpunkt abwendet?" (83–84). Densky argues that Kafka's speech, rather than simply advocacy for Löwy, advocates for the possibilities of what Yiddish could be, to speak for itself (92). This connection to speaking for the Yiddish theater and speaking for German-speaking Jews also appears in Kafka's animal stories, which are discussed later in the book. In Kafka's animal stories, speaking for Jewish people and speaking for animals, who cannot speak for themselves, come together to include such animals as the giant mole, the ape turned human Red Peter, and Josefine the Mouse Singer. The story "The Village Schoolmaster" features two rival advocates whose writings on the state of research of the giant mole leads to a social dispute. Red Peter's former life as an animal is also tested in various perspectives, most prominently Red Peter's report to the academy. Josefine the Mouse Singer is portrayed in a similar way in his thoughts on "small literature" and is reflected in how it performs as Yiddish as a pure performance that does not have to speak for anyone, which connects with Kafka's advocacy for Yiddish and Yiddish theater back in 1912. Kafka himself became the advocate for those who cannot speak for themselves. Densky also examines how the ability of people to advocate for themselves and others diminishes and almost disappears throughout the course of Kafka's three novels: Der Verschollene, Der Proceß, and Das Schloß. [End Page 136] In Der Verschollene, Karl Roßmann's successful advocacy for the eponymous stoker of the opening chapter becomes a transition from justice to discipline in the uncle's advocacy for Karl (141). While Karl Roßmann disappears into a fantastical theatricality in Der Verschollene, Josef K. in Der Proceß is brought into the dreamlike theatricality of his own trial (109–10). As in Der Verschollene, Josef K. must play a role in the court system that entwines him ever deeper within it, but he is ultimately unsuccessful in advocating for himself. Der Proceß opens with an act of Gegensprache rather than Fürsprache when Josef K. is marked as an alleged libeler in the speech of those in power, already diminishing his role as an advocate (109). In Der Proceß, Josef K.'s attack on the organization charging him inadvertently...

Numerical analysis of liquefaction-induced differential settlement of shallow foundations on an island slope

Seismic differential settlement of shallow foundations on an island slope with a liquefiable sand stratum can significantly reduce the foundation's bearing capacity. Now, most studies focused on the settlement of foundation, while few efforts have provided a description of the differential settlement of foundation. In this study, we therefore adopted an approach using three-dimensional (3D) nonlinear finite element (FE) simulation. A special case that the water table located at the interface between the liquefiable sand layer and the clay layer was employed in this model. A series of parametric studies involving soil properties, surcharge load, foundation location, and the typical shaking characteristics of earthquake events were conducted to identify their impact on liquefaction-induced differential settlement. Generally, a more permeable sand stratum and a larger cohesion of the upper clay stratum were found effective at decreasing differential settlement. A foundation's length/width ratio also played an important role in reducing differential settlement and, when the distance of the foundation from the crest of an island slope reached a critical value, the differential settlement tends towards a steady value. Heavily-loaded shallow foundations resulted in more differential settlement, leading to a reduction in their seismic bearing capacity. The peak ground acceleration and Arias intensity of an earthquake had a significant effect as well. In addition, some preliminary design considerations for shallow foundation under the earthquakes were proposed. Overall, the numerical results offer some valuable references to improve the design and construction of foundations on an island slope under the seismic loadings.

Effect of climate on asphalt pavement performance using two mechanistic-empirical methods

ABSTRACT The objective of this study is to assess the impact of climate on the performance of bituminous pavements with two different methods, and then to examine their impact on actual design scenarios. Three climate cases were selected for the comparisons involving the effect of temperature: one in France (Bordeaux) and two in the United States (Seattle and Phoenix). The case of an experimental site in Québec was also used for comparisons concerning consideration for seasonal variations in ground bearing capacity. The analyses were based on French (Alizé-LCPC) and US (AASHTOWare Pavement ME Design) mechanistic-empirical pavement design approaches. Interesting features of the two design methods are outlined and their fatigue cracking models are linked together. The results of the study highlight the importance, for design purposes, of the empirical fatigue equations as a function of temperature. For the site studied in France, the design results in terms of AC base layer thicknesses indicate that both methods show a similar trend with an increase in temperature. For the site in Québec, which is submitted to severe freeze/thaw cycles, the results show that taking temperature and moisture into account for unbound materials leads to a prediction of more severe permanent deformation. Highlights Presentation of two mechanistic-empirical (ME) methods for pavement design Description of the fatigue equations governing asphalt mixes for design purposes Identification of the parameters used in the design of pavement structures Study of the influence of the climate in France and Québec on pavement performance Comparison of the French and US methods for pavement design and correspondence between them

Evolution of arboreality and fossoriality in squirrels and aplodontid rodents: Insights from the semicircular canals of fossil rodents.

Reconstructing locomotor behaviour for fossil animals is typically done with postcranial elements. However, for species only known from cranial material, locomotor behaviour is difficult to reconstruct. The semicircular canals (SCCs) in the inner ear provide insight into an animal's locomotor agility. A relationship exists between the size of the SCCs relative to body mass and the jerkiness of an animal's locomotion. Additionally, studies have also demonstrated a relationship between SCC orthogonality and angular head velocity. Here, we employ two metrics for reconstructing locomotor agility, radius of curvature dimensions and SCC orthogonality, in a sample of twelve fossil rodents from the families Ischyromyidae, Sciuridae and Aplodontidae. The method utilizing radius of curvature dimensions provided a reconstruction of fossil rodent locomotor behaviour that is more consistent with previous studies assessing fossil rodent locomotor behaviour compared to the method based on SCC orthogonality. Previous work on ischyromyids suggests that this group displayed a variety of locomotor modes. Members of Paramyinae and Ischyromyinae have relatively smaller SCCs and are reconstructed to be relatively slower compared to members of Reithroparamyinae. Early members of the Sciuroidea clade including the sciurid Cedromus wilsoni and the aplodontid Prosciurus relictus are reconstructed to be more agile than ischyromyids, in the range of extant arboreal squirrels. This reconstruction supports previous inferences that arboreality was likely an ancestral trait for this group. Derived members of Sciuridae and Aplodontidae vary in agility scores. The fossil squirrel Protosciurus cf. rachelae is inferred from postcranial material as arboreal, which is in agreement with its high agility, in the range of extant arboreal squirrels. In contrast, the fossil aplodontid Mesogaulus paniensis has a relatively low agility score, similar to the fossorial Aplodontia rufa, the only living aplodontid rodent. This result is in agreement with its postcranial reconstruction as fossorial and with previous indications that early aplodontids were more arboreal than their burrowing descendants.

Prevalence and Genotypes of Cryptosporidium in Wildlife Populations Co-Located in a Protected Watershed in the Pacific Northwest, 2013 to 2016.

Between October 2013 and May 2016, 506 scat samples were collected from 22 species of wildlife located in a protected watershed of a major municipal water supply in the Pacific Northwest, USA. Overall prevalence of Cryptosporidium in the wildlife scat was 13.8% (70/506), with 15 species of wildlife found positive for Cryptosporidium. Prevalence of Cryptosporidium varied among species of wildlife, with higher prevalences observed in cougars (50.0%), mountain beavers (40.0%), and bobcats (33.3%), but none of these species are riparian-dependent. Genotyping of Cryptosporidium by sequencing PCR amplicons from the 18S rRNA gene were successful for seven species of wildlife, including bobcat, unknown predator, black-tailed deer, deer mouse, snowshoe hare, mountain beaver, and western spotted skunk. BLAST and phylogenetic analyses indicated that multiple species and genotypes of Cryptosporidium were present, with some isolates possibly co-circulating within and between wildlife populations in this protected watershed. Evidence of oocyst exchange between infected prey and their predators was also found. During the study period, several zoonotic Cryptosporidium species and genotypes that are uncommon in humans were detected in bobcat (99.58% identical to Cryptosporidium felis), unknown predator (100% identical to Cryptosporidium canis), snowshoe hare (100% identical to Cryptosporidium sp. skunk genotype), and mountain beaver (100% identical to Cryptosporidium ubiquitum). Novel sequences were also found in mountain beaver. To our knowledge, this is the first published report of a unique genotype or species of Cryptosporidium in mountain beaver (Aplodontia rufa).