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Youth purpose was investigated using a two-phase embedded design with youth participating in Scouts BSA (N = 3,943), ages 9–20 (M = 14.0, SD = 1.9). Participating Scouts were mostly White (91%) and male (98%). In Phase 1, we conducted a two-step cluster analysis on Scouts' survey responses to three purpose dimensions (personal meaning, goal-directedness, beyond-the-self orientation). Four clusters emerged: Purposeful, Explorers, Dreamers, Nonpurposeful. In Phase 2, we explored qualities of purpose within each cluster and programmatic features and relationships within the scouting context fostering youth purpose with a Scout subsample (N = 30) who completed semi-structured interviews. Results demonstrated that adults supporting scouting, inspiration from older peers, and opportunities to help others and explore new activities supported youth purpose. [ABSTRACT FROM AUTHOR]

Drawing from the Sheldon and Manktelow collections at SUNY Oswego's Penfield Library, along with sociological criteria for a profession – graduate-level training, autonomy, peer evaluation and responsibility to the public – this article reassesses Oswego State Normal School's impact on nineteenth-century teacher education. Descriptions of Oswego identify the school as an active site of object teaching and Pestalozzianism in the US. Yet, as this analysis reveals, Edward Austin Sheldon and Oswego's faculty oversaw the development of practices and innovations that were designed to enhance teacher autonomy and to involve teachers in their own learning and evaluation. With Oswego's reputation for innovation spreading, Sheldon took responsibility to describe and defend the teacher preparation work conducted at Oswego. This article argues that Oswego should be remembered not just for the promotion of object teaching and Pestalozzian principles, but also for its efforts to leverage such practices and principles to cultivate a stronger teaching profession. [ABSTRACT FROM AUTHOR]

Dr. Martha Jane Powell was a distinguished chytrid taxonomist and mentor who made significant contributions to the field of mycology. She began her career studying chytrid fungi and later focused on using zoospore ultrastructure to revise chytrid taxonomy. She also conducted research on host-parasite interactions and worked with various organisms including oomycetes and the clade that includes Rozella. Throughout her career, she mentored numerous students and authored over 160 papers and book chapters. Dr. Powell's impact on the field of mycology and her dedication to her students are remembered and celebrated. [Extracted from the article]

Lung cancer patients treated with targeted therapies frequently respond well but invariably relapse due to the development of drug resistance. Drug resistance is in part mediated by a subset of cancer cells termed "drug-tolerant persisters" (DTPs), which enter a dormant, slow-cycling state that enables them to survive drug exposure. DTPs also exhibit stem cell-like characteristics, broad epigenetic reprogramming, altered metabolism, and a mutagenic phenotype mediated by adaptive mutability. While several studies have characterised the transcriptional changes that lead to the altered phenotypes exhibited in DTPs, these studies have focused predominantly on protein coding changes. As long non-coding RNAs (lncRNAs) are also implicated in the phenotypes altered in DTPs, it is likely that they play a role in the biology of drug tolerance. In this review, we outline how lncRNAs may contribute to the key characteristics of DTPs, their potential roles in tolerance to targeted therapies, and the emergence of genetic resistance in lung adenocarcinoma. [ABSTRACT FROM AUTHOR]

The purpose of this study is to investigate challenges and tensions encountered by university supervisors working with student teachers in dual language immersion (DLI) settings. Despite the growth of Utah’s statewide DLI program, Utah university teacher programs have few faculty members familiar with the partner cultures and languages of Utah’s DLI model. Drawing from a larger multiple case study, this study examines three non-Chinese university supervisors’ written reflections and focus group transcripts during supervision in Chinese DLI classrooms. Findings suggest the challenges and tensions encountered by these supervisors were not just cultural in nature; at times, university supervisors were unfamiliar with the DLI model and/or unsure of whether challenges were products of cultural differences, the DLI program, or other influences [ABSTRACT FROM AUTHOR]

The Mesoproterozoic Husky Creek Formation is an interlayered redbed and basalt package that overlies a ca. 2.5 km thick, regionally extensive basaltic plateau linked to the 1.27 Ga Mackenzie Large Igneous Province. This succession provides an opportunity to study the interaction between contemporaneous fluvial sedimentation and flood basalt volcanism. The Husky Creek Formation is approximately 1900 m thick, consisting predominantly of fluvial channel and subordinate floodplain and eolian strata dominated by lithic detritus intercalated with basalt flows. U–Pb dating of detrital zircon grains collected from four stratigraphic levels in the Husky Creek Formation reveals two main age groupings: (1) a 1270 Ma peak attributed to the Mackenzie Large Igneous Province; and (2) Pre-1.6 Ga detrital zircon ages, which reflect sources from a broad region of northwestern Laurentia and are interpreted to be recycled from underlying sedimentary rocks of the Hornby Bay Basin. An upsection decrease in the proportion of ca. 1270 Ma zircon grains, coupled with increasing sandstone compositional maturity, reflects the expansion of the drainage basin during burial of a volcanic pile, with recycling becoming more dominant as the Husky Creek Formation accumulated. The Husky Creek Formation was deposited in the waning stages of the Mackenzie Igneous Event by west-flowing rivers into a geographically restricted basin above an extensive mafic volcanic plateau. This paper provides insight into fluvial basin development during the aftermath of one of Earth's largest igneous events. [ABSTRACT FROM AUTHOR]

Plate tectonics is a fundamental factor in the sustained habitability of Earth, but its time of onset is unknown, with ages ranging from the Hadaean to Proterozoic eons1–3. Plate motion is a key diagnostic to distinguish between plate and stagnant-lid tectonics, but palaeomagnetic tests have been thwarted because the planet’s oldest extant rocks have been metamorphosed and/or deformed4. Herein, we report palaeointensity data from Hadaean-age to Mesoarchaean-age single detrital zircons bearing primary magnetite inclusions from the Barberton Greenstone Belt of South Africa5. These reveal a pattern of palaeointensities from the Eoarchaean (about 3.9 billion years ago (Ga)) to Mesoarchaean (about 3.3 Ga) eras that is nearly identical to that defined by primary magnetizations from the Jack Hills (JH; Western Australia)6,7, further demonstrating the recording fidelity of select detrital zircons. Moreover, palaeofield values are nearly constant between about 3.9 Ga and about 3.4 Ga. This indicates unvarying latitudes, an observation distinct from plate tectonics of the past 600 million years (Myr) but predicted by stagnant-lid convection. If life originated by the Eoarchaean8, and persisted to the occurrence of stromatolites half a billion years later9, it did so when Earth was in a stagnant-lid regime, without plate-tectonics-driven geochemical cycling.Magnetic palaeointensity data from the Barberton Greenstone Belt (South Africa) as well as the Jack Hills (Western Australia) show nearly constant palaeofield values between 3.9 Ga and 3.4 Ga, providing evidence for stagnant-lid mantle convection. [ABSTRACT FROM AUTHOR]

The purpose of this study is to examine the professional development (PD) needs of Chinese dual language immersion program (DLI) educators, particularly the PD supports these teachers receive. This instrumental case study examined the professional learning of four Chineselanguage DLI teachers through semi-structured interviews and observations of classroom teaching and PD trainings. Findings suggest the Utah DLI model indelibly shapes teachers' work and learning as teachers. Chinese DLI teachers also identify needs that are particular to their teaching role like adapting/translating resources; however, the findings also confirm other scholarship indicating Chinese DLI teachers' particular needs are not well supported. PD received by participants was general in nature, rather than differentiated for Chinese DLI teachers' needs. [ABSTRACT FROM AUTHOR]

The growth of Utah's dual language immersion (DLI) program has led to situations where student and mentor teachers teach in settings far different from their home countries' schools, while supervisors observe lessons in unfamiliar languages. This study examined critical incidents in a cross-cultural student teaching experience consisting of a student teacher teaching in a Chinese DLI classroom and supported by a Chinese mentor and a non-Chinese speaking university supervisor. We collected and analyzed audio from dyad meetings, from a triad meeting, and also audio from one-on-one interviews. Our findings raise questions about differences in how teaching is discussed between triad members, as well as whether such student teaching arrangements inhibit student teacher growth due to language or cultural barriers. [ABSTRACT FROM AUTHOR]

Petrological modeling and geochronology (Lu–Hf garnet, U–Pb monazite, zircon, and titanite) for seven mid-amphibolite to granulite-facies metamorphic rocks in the Thelon tectonic zone (Ttz) provide new insights into the evolution of this orogen. A Grt-Sp-Sil diatexite records 2.01–2.00 Ga garnet and monazite growth during >830 °C contact metamorphism associated with voluminous convergent margin plutonism. The most widespread, 1.96–1.90 Ga metamorphism is associated with clockwise pressure (P)–temperature (T) paths, indicating it was driven by crustal thickening. Earlier (1.96–1.92 Ga) and lower temperature (630 °C–730 °C; 6–8 kbar) metamorphism in the eastern Slave craton contrast with ∼860 °C (7.5 kbar), 1.91–1.90 Ga diatexites in the central, Paleoproterozoic plutonic rock-dominated, core of the Ttz. These differences are interpreted to reflect lower vs. upper plate settings, respectively. A contribution of mantle heat is suggested by the counter-clockwise P–T path and 885 °C (5.7 kbar) conditions recorded by diatexite associated with c. 1.9 Ga peraluminous leucogranite that dominates a corridor along the Ttz–Rae craton boundary. A tectonic model is proposed wherein the Ttz evolved at an accretionary margin after rifting of Ttz microcontinent (mTtz) off the Rae craton at c. 2.2–2.1 Ga. Voluminous plutonism at 2.01–1.98 Ga formed via east-dipping subduction under mTtz. Following 1.97 Ga collision of the Slave craton and mTtz, west-dipping subduction generated 1.96–1.95 Ga plutonism in the composite mTtz-Slave upper plate. Collision of Rae craton at 1.95–1.94 Ga led to crustal thickening, widespread 1.91–1.90 Ga high-grade metamorphism and extensive crustal melting in the central Ttz. [ABSTRACT FROM AUTHOR]

The purpose of this case study was to examine Utah's Grades 1-6 social studies standards and the instructional resources provided by the state for Chinese Dual Language Immersion (DLI) teachers to investigate how social studies instruction supported cultural learning for DLI students. A collaborative, Didaktik analysis of the standards and resources found that, in Grades 1-3 and 6, during which the partner-language DLI teacher is responsible for social studies, Chinese cultural knowledge or learning was not explicitly emphasized within the instructional resources provided in Grades 1-3. The one possible example found was in Grade 6, which included extensive materials for lessons on ancient Chinese civilization and culture. Despite this well-developed set of resources, it was unclear whether ancient China constituted a topic unique to the Chinese DLI program social studies classes or if this was a topic that might be learned by both DLI and non-DLI students across the state. Available resources explicitly encourage Chinese DLI teachers to teach American and Utah cultural traditions, but not necessarily the partner language's cultural traditions. The lack of focus on partner-language culture raises questions for both second language learning in DLI settings and DLI teacher professional development. [ABSTRACT FROM AUTHOR]

First‐generation college students (FGCS) face unique challenges compared to non‐first‐generation peers. Lack of personal, emotional, financial, or psychological support may create difficulties adapting to college. The focus on affordability in higher education and lowering the cost of a bachelor's degree has also made the transfer process an essential part of degree completion for many, with only 41% of transfer students pursuing a bachelor's degree will achieve that goal. Research has made the connection that diminished personal support from parental figures may impact the mental health of FGCS transfer students, leading to higher dropout, lower retention, and lower degree completion rates. Students who experienced increased personal support might experience fewer mental health issues, resulting in a higher chance of degree completion. Future research implications include prioritizing support systems and mental health services to aid FGCS and transfer students lacking personal support in degree completion. [ABSTRACT FROM AUTHOR]

This instrumental case study explored non-formal educators' lay theories of adolescence using the case of the Boy Scouts of America's Scouts BSA program, a co-ed program serving youth between the ages of 11 and 17. We conducted an iterative analysis of 110 structured interviews with Scouts BSA adult volunteer leaders who served as scoutmasters or assistant scoutmasters. Results indicated that participants discussed adolescence in terms of youth characteristics as well as processes youth underwent during their adolescent years. These adults sometimes viewed adolescence as idiosyncratic, identifying differences in learning, behavior, and family situations among youth, particularly those whom they had identified as exhibiting specific challenges like autism. The results also illustrated relationships between the program and lay theories of adolescence. Namely, core Scouts BSA programmatic structures and expectations such as operating the patrol/troop method hierarchies, building leadership skills, camping or outdoor activities, and including all youth in activities influence participants' own views of adolescence, including their views of adolescence as a time to cultivate maturity and independence. The study concludes with a brief discussion of results and limitations of the study, including recommendations for training and additional research. [ABSTRACT FROM AUTHOR]

The Patterson Lake corridor is a new uranium district located on the southwestern margin of the Athabasca Basin. Known resources extend almost 1 km below the unconformity in graphite- and sulfide-bearing shear zones within highly altered metamorphic rocks. Despite different host rocks and greater depths below the unconformity, alteration assemblages (chlorite, illite, kaolinite, tourmaline and hematite), ore grades and textures are typical of unconformity-related deposits. This alteration includes at least three generations of Mg-rich tourmaline (magnesio-foitite). The boron isotopic composition of magnesio-foitite varies with generation: the earliest generation, which is only observed in shallow samples from the Triple R deposit (Tur 1), contain the heaviest isotopic signature (δ 11B ≈ 19–26‰), whereas subsequent generations (Tur 2 and Tur 3) yield lighter and more homogeneous isotopic signatures (δ 11B ≈ 17.5–19.9‰). These results are consistent with precipitation from low-temperature, NaCl- and CaCl2-rich brine(s) derived from an isotopically heavy boron source (e.g. evaporated seawater) that interacted with tourmaline and silicates in the basement rocks and/or fluids derived from depth (with low δ 11B values). The lower δ 11B values in paragenetically later magnesio-foitite reflect greater contributions of basement-derived boron over time, whereas minor compositional variations reflect local metal sources (e.g. Cr, V, Ti) and evolving fluid chemistry (decreasing Na and Ca, increasing Mg) over time. The δ 11B and chemical variation in magnesio-foitite over time reinforce the strong interactions with basement rocks in these systems while supporting incursion of basinal brines well below the unconformity contact. Supplementary material: Complete analytical dataset including reference materials are available at https://doi.org/10.6084/m9.figshare.c.5727555 Thematic collection: This article is part of the Uranium Fluid Pathways collection available at: https://www.lyellcollection.org/cc/uranium-fluid-pathways [ABSTRACT FROM AUTHOR]

This intrinsic case study analyzed the community-based framing of the work of Educators Rising, a nationwide organization that aims to develop a pipeline between secondary students and the teaching profession. Using TribalCrit to examine publicly available documents, videos, and websites, the study found Educators Rising primarily framed community as a place: communities are physical locations that need teachers, the original impetus for Educators Rising's existence and work. Through its partnerships with schools and districts, Educators Rising seeks to cultivate market-oriented views of knowledge and teaching in these communities. The organization's standards and activities privilege certain academic knowledge over cultural knowledge. Building from this view of certain academic knowledge, Educators Rising packages conceptions of teaching forged by external entities like the National Board for Professional Teaching Standards, which participants are expected to assimilate through their involvement in the organization. Additionally, Educators Rising attempts to enforce assimilation of external conceptions of teaching through competitions and micro-credentials. Communities, from Educators Rising's perspective, are sites to assimilate certain knowledge and narrow conceptions of teaching and teacher learning, primarily through student participation in competitive activities. Recommendations for effective partnerships are discussed. [ABSTRACT FROM AUTHOR]

Plantago princeps var. princeps is an endangered native Hawaiian plant, and part of the recovery plan includes repopulation using plants grown in a nursery. However, disease pressure from downy mildew is hindering repopulation efforts. The organism associated with the downy mildew was determined to be a Peronospora species with brown, ellipsoid conidia measuring 21 by 16 µm on average, which was morphologically different from validly described species of Peronospora that infect Plantago species, but it was morphologically similar to the invalidly published species Peronospora lanceolatae (Art. 40.1). Comparison of mitochondrial cytochrome oxidase subunit I (cox1), mitochondrial cytochrome oxidase subunit II (cox2), nuclear internal transcribed spacer (ITS), and nuclear 28S rRNA D1–D2 (28S) loci revealed the unknown Peronospora to be molecularly divergent from Peronospora alta and Peronsopora plantaginis, but very similar to Peronospora from Plantago lanceolata, the type host of P. lanceolatae. Phylogenetic trees inferred with maximum likelihood and Bayesian inference from a concatenated alignmaent and individual gene trees confirmed the divergence of the unknown Peronospora from P. alta and P. plantaginis and its similarity to P. lanceolatae. However, attempts to inoculate Plantago lanceolata with the strain from Plantago princeps var. princeps were unsuccessful, which, in conjunction with divergence in ITS, suggests that the unknown Peronospora is specific to Plantago princeps var. princeps. Herein, the Peronospora strain on Plantago princeps var. princeps is described as the new species Peronospora kuewa based on morphology, molecular phylogenetics, and host specificity. In addition, Peronospora gaponenkoae is described here to honor Nina Ivanova Gaponenko on the basis of her description of P. lanceolatae. [ABSTRACT FROM AUTHOR]

Motivation Whole-genome sequencing of uncultured eukaryotic genomes is complicated by difficulties in acquiring sufficient amounts of tissue. Single-cell genomics (SCG) by multiple displacement amplification provides a technical workaround, yielding whole-genome libraries which can be assembled de novo. Downsides of multiple displacement amplification include coverage biases and exacerbation of contamination. These factors affect assembly continuity and fidelity, complicating discrimination of genomes from contamination and noise by available tools. Uncultured eukaryotes and their relatives are often underrepresented in large sequence data repositories, further impairing identification and separation. Results We compare the ability of filtering approaches to remove contamination and resolve eukaryotic draft genomes from SCG metagenomes, finding significant variation in outcomes. To address these inconsistencies, we introduce a consensus approach that is codified in the SCGid software package. SCGid parallelly filters assemblies using different approaches, yielding three intermediate drafts from which consensus is drawn. Using genuine and mock SCG metagenomes, we show that our approach corrects for variation among draft genomes predicted by individual approaches and outperforms them in recapitulating published drafts in a fast and repeatable way, providing a useful alternative to available methods and manual curation. Availability and implementation The SCGid package is implemented in python and R. Source code is available at http://www.github.com/amsesk/SCGid under the GNU GPL 3.0 license. Supplementary information Supplementary data are available at Bioinformatics online. [ABSTRACT FROM AUTHOR]

Determining the age of the geomagnetic field is of paramount importance for understanding the evolution of the planet because the field shields the atmosphere from erosion by the solar wind. The absence or presence of the geomagnetic field also provides a unique gauge of early core conditions. Evidence for a geomagnetic field 4.2 billion-year (Gy) old, just a few hundred million years after the lunar-forming giant impact, has come from paleomagnetic analyses of zircons of the Jack Hills (Western Australia). Herein, we provide new paleomagnetic and electron microscope analyses that attest to the presence of a primary magnetic remanence carried by magnetite in these zircons and new geochemical data indicating that select Hadean zircons have escaped magnetic resetting since their formation. New paleointensity and Pb-Pb radiometric age data from additional zircons meeting robust selection criteria provide further evidence for the fidelity of the magnetic record and suggest a period of high geomagnetic field strength at 4.1 to 4.0 billion years ago (Ga) that may represent efficient convection related to chemical precipitation in Earth's Hadean liquid iron core. [ABSTRACT FROM AUTHOR]

Background: This comparative case study investigates 2 successful community trail initiatives, using the Active Living By Design (ALBD) Community Action Model as an analytical framework. The model includes 5 strategies: preparation, promotion, programs, policy, and physical projects. Methods: Key stakeholders at 2 sites participated in in-depth interviews (N = 14). Data were analyzed for content using Atlas Ti and grouped according to the 5 strategies. Results: Preparation: Securing trail resources was challenging, but shared responsibilities facilitated trail development. Promotions: The initiatives demonstrated minimal physical activity encouragement strategies. Programs: Community stakeholders did not coordinate programmatic opportunities for routine physical activity. Policy: Trails' inclusion in regional greenway master plans contributed to trail funding and development. Policies that were formally institutionalized and enforced led to more consistent trail construction and safer conditions for users. Physical Projects: Consistent standards for wayfinding signage and design safety features enhanced trail usability and safety. Conclusions: Communities with different levels of government support contributed unique lessons to inform best practices of trail initiatives. This study revealed a disparity between trail development and use-encouragement strategies, which may limit trails' impact on physical activity. The ALBD Community Action Model provided a viable framework to structure cross-disciplinary community trail initiatives. [ABSTRACT FROM AUTHOR]

Previous molecular phylogenetic studies have shown that families in Zoopagales are not monophyletic. To test the monophyly of genera and species in the order, we used a single-cell approach to generate nuclear 18S rRNA (18S) sequences for 10 isolates representing nine taxa. We provide the first sequences for the genus Zoopage and additional sequences for taxa in Cocholonema, Acaulopage, and Zoophagus. Our results reveal that Zoophagus, Zoopage, and Acaulopage tetraceros are not monophyletic. We conclude that morphology alone is not sufficient to delineate genera and species in the order and encourage studies that increase genetic sampling of taxa including type species. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Earth Sciences is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In response to a recent article in the KDP Record on recruiting teachers of color, the author explores a recruitment factor that the earlier article does not address: what students of color have already learned about teaching. Suggested changes for teacher education are offered. [ABSTRACT FROM AUTHOR]

Downy mildew disease was observed for the first time from Lipochaeta integrifolia, a G3-vulnerable plant native to Hawai'i. The oomycete infecting the plants was identified as Plasmopara sphagneticolae by morphological and molecular means. This marks the first report of P. sphagneticolae outside of Australia on a new host. This disease may have significant implications for conservation efforts of L. integrifolia and other endangered native Asteraceae on the islands. [ABSTRACT FROM AUTHOR]

Food webs in temporary forest ponds are driven by decomposition of terrestrial inputs. Chytrid fungi are important components of the fungal community, degrading leaf litter in streams reliant on terrestrial inputs and in lake ecosystems where they may stabilize the food web. However, little is known about chytrid fungi in temporary forest ponds. We inventoried the chytrid diversity present in two temporary forest ponds via light microscopy of baited samples and ion semiconductor (Ion Torrent) sequencing of environmental DNA. We quantified trends of chytrid alpha and beta diversity as a function of spatial and temporal factors. A total of 59 chytrid taxa were detected throughout the study. Beta diversity exhibited variation across the sampled months for both the entire fungal community as well as for chytrids alone. Shifts in community composition were also apparent, although diversity metrics and composition patterns did not meet adjusted P values. The results of this study highlight the diversity of chytrid fungi in temporary forest ponds and the need for further studies on the spatial and temporal dynamics of chytrid species. [ABSTRACT FROM AUTHOR]

U-Pb ages of zircon from bentonites within the upper Cretaceous Bastion Ridge and Kanguk formations, Sverdrup Basin, provide constraints on sedimentation rates, biostratigraphic correlations, timing of Oceanic Anoxic Event 2 (OAE2) in the High Arctic, and the late magmatic history of the High Arctic Large Igneous Province (HALIP). A late Cenomanian to early Turonian age for the base of the Kanguk Formation is confirmed that supports correlations of the global OAE2 in the High Arctic. Sedimentation rates varied from 19 m Ma-1 between 93 and 91 Ma to 26 m Ma-1 between 91 and 83 Ma at Axel Heiberg Island. At Ellef Ringnes Island, the lower Kanguk Formation records high rates of ~70 mMa-1 between 94 and 93 Ma, which decrease to rates comparable to those of the upper Axel Heiberg section. Differences in sedimentation rates may reflect differences in setting prior to the major transgression in the latest Cenomanian to early Turonian. The timing of Arctic occurrences of the Scaphites nigricollensis and Scaphites depressus ammonite zones is shown to be broadly comparable to that of lower-latitude occurrences within the Western Interior Seaway. An eruption frequency of 0.5-2.5 Ma characterizes the late alkaline phase of HALIP magmatism. Volcanic bed thicknesses of 10-50 cm suggest ash transport distances of less than 1000 km. Long-lived volcanic centres, in the area of the Alpha Ridge, northern Ellesmere Island or northern Greenland, were the likely source of volcanic ash over a period of 10-15 Ma. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Earth Sciences is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Earth Sciences is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Earth Sciences is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Zoospore ultrastructural characters combined with molecular phylogenetic hypotheses have been used to revise the taxonomy of zoosporic true fungi. An example is the reclassification of Rhizophlyctis rosea-like fungal strains into four new families and three new genera within the order Rhizophlyctidales. One genus was Borealophlyctis, which included a Canadian isolate, DAOMC 229843. A recent survey of chytrid diversity in Alabama (USA) yielded additional strains (WJD 170, WJD 171) in the Borealophlyctis lineage. With light and transmission-electron microscopy we examined strains DAOMC 229843, WJD 170 and WJD 171. We also analyzed partial nuc 28S rDNA D1-D3 domains (28S) and nuc rDNA region encompassing the internal transcribed spacers 1 and 2 and 5.8S (ITS) sequences to determine the phylogenetic placement of the strains within Rhizophlyctidales. Based on molecular divergence and morphological differences from the type Borealophlyctis paxensis, we recognize DAOMC 229843, WJD 170 and WJD 171 as representatives of the new species Borealophlyctis nickersoniae. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Earth Sciences is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Many chytrid phylogenies contain lineages representing a lone taxon or a few organisms. One such lineage in recent molecular phylogenies of Rhizophydiales contained two marine chytrids, Rhizophydium littoreum and Rhizophydium aestuarii. To better understand the relationship between these organisms, we increased sampling such that the R. littoreum/R. aestuarii lineage included 10 strains of interest. To place this lineage in Rhizophydiales, we constructed a molecular phylogeny from partial nuc 28S rDNA D1-D3 domains (28S) of these and 80 additional strains in Rhizophydiales and examined thallus morphology and zoospore ultrastructure of our strains of interest. We also analyzed sequences of the nuc rDNA region encompassing the internal transcribed spacers 1 and 2, along with the 5.8S rDNA (ITS) of our 10 strains of interest to assess sequence similarity and phylogenetic placement of strains within the lineage. The 10 strains grouped together in three well supported clades: (i) Rhizophydium littoreum + Phlyctochytrium mangrovei, (ii) three strains of Rhizophydium aestuarii and (iii) five previously unidentified strains. Light microscopic observations revealed four distinct thallus morphologies, and zoospore ultrastructural analyses revealed four distinct constellations of ultrastructural features. On the bases of morphological, ultrastructural and molecular evidence we place these strains in the new family Halomycetaceae and four new genera (Halomyces, Paludomyces, Ulkenomyces, Paranamyces) in Rhizophydiales. [ABSTRACT FROM AUTHOR]

Chytriomyces is a complex genus in Chytridiales. The morphological concept of the genus expanded as new taxa were added, and studies of zoospore ultrastructure and molecular phylogenies have revealed the genus to be polyphyletic. One problematic taxon is C. spinosus Fay, a distinctive species characterized by whorls of spines on the zoosporangium and a large accumulation of vesicle material beneath the operculum. With light-, scanningelectron and transmission-electron microscopy, we examined a culture (WJD186) isolated from a muck sample collected from a temporary forest pond. We also analyzed the D1-D2 variable domains of the nuc 28S rDNA (28S) sequences to confirmthe phylogenetic placement of the species relative to the type of Chytriomyces, C. hyalinus Karling. The morphology of culture WJD186 is consistent with features Fay described for C. spinosus, and the zoospore ultrastructure is consistent with the Group I-type zoospore characters of Chytriomycetaceae (Chytridiales). In our molecular phylogeny C. spinosus does not group with the type of Chytriomyces. Consequently, we erect a new genus in Chytriomycetaceae and present the new combination Fayochytriomyces spinosus. [ABSTRACT FROM AUTHOR]

This study analyzed two teachers and their student and teacher behavioral systems to determine whether discipline-specific ongoing education may play a role in developing expertise in physical education. Field systems analysis (FSA) was used to analyze the teachers' and their students' systems. Interviews supplemented the behavioral systems data. Both teachers received training from the same undergraduate physical education program, were of the same gender, and had the same years of experience. The same content was taught to the same number of students in one physical education lesson. The results exhibited differences in each teacher's behavioral system, as the teacher with ongoing education within-field exhibited a higher percentage of instructional elements that were more common, complex, and predictable in their elemental chains. The teacher who received ongoing education out-of-field exhibited more managerial elements in his behavior system and exhibited less common, complex, and predictable elemental chains. The students' data exhibited much of the same phenomena, as the within-field teacher's students exhibited more content learning elements that were more common, complex, and predictable in their elemental chains. The out-of-field teacher's students exhibited more noncontent learning elements and exhibited less common, complex, and predictable elemental chains. Interview data supported the behavioral systems data. [ABSTRACT FROM AUTHOR]

New U-Pb zircon dates from gneissic xenoliths in an Early Cambrian lamprophyre point to late Mesoproterozoic metamorphism and magmatism in the crust beneath northern Yukon. The data indicate a previously unrecognized thermal event in Yukon and extend the recognition of widely spaced 1.3-1.0 Ga igneous, metamorphic and tectonic events along the western margin of Laurentia. Together, these events demonstrate that the north-western margin of Laurentia was thermally active during a period of traditionally inferred tectonic quiescence. The tectonic setting, intensity and general nature of this late Mesoproterozoic tectonothermal activity are poorly constrained, but their recognition is key to expanding our understanding of the Proterozoic geology of North America. The recognition of this event places new constraints on the palaeotectonic reconstructions of the supercontinent Rodinia. [ABSTRACT FROM AUTHOR]

Terra Nova, 23, 92-99, 2011 Abstract Zircon crystallization ages for a syntectonic granite and an associated dyke along the Tangtse strand of the Karakorum fault are 18.5 ± 0.2 and 18.6 ± 0.2 Ma, respectively. A dyke cross-cutting the foliation in the Karakorum shear zone (Ksz) yielded an age of 16.0 ± 0.6 Ma. These data show that the Ksz was associated with significant granitic magmatism and was active before 16 Ma, since at least c. 18.5 Ma. Consideration of other data along the Karakorum fault suggests that the fault has most likely been active since c. 22.7-25 Ma at a rate of 8-13 mm a−1. This study conducted in the frontal part of the Himalayan orogen shows that large continental strike-slip faults can be linked with magmatism and be stable for more than 20 Ma, even in the hottest part of the orogen where strain localization is supposed to be at a minimum. [ABSTRACT FROM AUTHOR]

The Boothia mainland region of the north-central Rae domain is underlain by remnants of a Neoarchean volcano sedimentary sequence dismembered by two regionally extensive Neoarchean high-potassium granitoid suites with rare occurrences of a structurally interleaved, Paleoproterozoic sedimentary cover sequence. The granitoids and their gneissic equivalents are dominated by variably deformed and metamorphosed I-type, metaluminous, polyphase, commonly porphyritic to augen, biotite ±hornblende monzogranite, and subordinate granodiorite, with rare tonalite. New geochronological results, the first for this area, demonstrate that the widespread Neoarchean granitoid plutonism is dominantly 2.61-2.59 Ga, with a less prominent 2.66 Ga plutonic event. The age of zircon recrystallization suggests that ca. 2.60 Ga Archean metamorphism and fabric development (S1) affected the 2.66 Ga plutons prior to or contemporaneously with intrusion of the voluminous ca. 2.6 Ga suite. εNd(t) for the ca. 2.61-2.59 Ga suite range from 1.4 to -1.9, overlapping with the ca. 2.66 Ga suite that range from 1.4 to 1.5. The Nd isotopic data, coupled with the presence of inherited ca. 2.65, 2.70, and 2.85-2.90 Ga zircon, suggests recycling of older, Neoarchean to Mesoarchean crust in the formation of these suites. Metaplutonic rocks preserve Paleoproterozoic deformation (F4 and F5) and amphibolite-facies metamorphism, sporadically recorded in zircon rims that formed at 1.81 Ga. This event strongly reoriented the Neoarchean fabrics in metaplutonic rocks, generally without the development of a new coaxial Paleoproterozoic fabric, and we attribute this strain and metamorphism to the Hudsonian orogeny. La région terrestre Boothia du domaine Rae centre-nord repose sur des vestiges d'une séquence volcano-sédimentaire datant du Néoarchéen; cette séquence est démembrée par deux suites granitoïdes d'échelle régionale, à teneur élevée en potassium et possédant de rares occurrences d'une séquence structurellement intercalée d'une couverture sédimentaire datant du Paléoprotérozoïque. Les granitoïdes et leurs équivalents gneissiques sont dominés par un monzogranite à déformation variable, métamorphisé, de type I, métalumineux, polyphasé, souvent porphyrique à oeillé et à biotite hornblende avec une granodiorite subordonnée et une rare tonalite. De nouveaux résultats géochronologiques, les premiers pour ce secteur, démontrent que le plutonisme granitoïde néoarchéen étendu date surtout de 2,61 à 2,59 Ga, avec un événement plutonique moins important vers 2,66 Ga. L'âge de la recristallisation du zircon suggère que, vers 2,60 Ga, le métamorphisme archéen et le développement de la fabrique (S1) aient affecté les plutons âgés de 2,66 Ga avant ou en même temps que l'intrusion de la volumineuse suite vers 2,6 Ga. Les valeurs εNd(t) pour la suite datant de ~ 2,61 à 2,59 Ga varient de 1,4 à -1,9, chevauchant la suite datant ~2,66 Ga, dont les valeurs εNd(t) varient de 1,4 à 1,5. Les données d'isotopes Nd, jumelées à la présence de zircons hérités dont les âges sont ~2,65, 2,70 et 2,85-2,90 Ga, suggèrent un recyclage de l'ancienne croûte néoarchéenne à mésoarchéenne pour la formation de ces suites. Des roches métaplutoniques ont préservé la déformation paléoprotérozoïque (F4 et F5) ainsi que le métamorphisme au faciès des amphibolites, retrouvé sporadiquement dans les bordures des zircons qui se sont formées à 1,81 Ga. Cet événement a grandement réorienté les fabriques néoarchéennes dans les roches métaplutoniques, généralement sans le développement d'une nouvelle fabrique coaxiale paléoprotérozoïque; nous attribuons cette déformation et ce métamorphisme à l'orogenèse hudsonienne. [ABSTRACT FROM AUTHOR]

The Changgo culmination, one of the North Himalayan domes in south central Tibet, consists of a multiphase granite core surrounded by a deformed metasedimentary carapace. The granitic core records general non-coaxial shear with a top-to-the-south sense shear component. The contact between the core and the carapace is a shear zone, characterized by general non-coaxial shear with a top-to-the-north shear sense, interpreted to be the northern continuation of the South Tibetan detachment system (STDS). The shear zone contains lenses of leucogranite dated at 35.4 Ma. This is interpreted to reflect Eocene crustal thickening, coeval with the earliest shortening event recorded in the carapace. The main phase of the Changgo granite crystallized at 23.5 Ma, while undeformed aplite dikes, the youngest phase observed in the granite, were intruded at 22.1 Ma. Aplite dikes crosscut the main deformation fabric within the Changgo granite; therefore, that deformation and associated south directed shearing must have ended between 23.5 Ma and 22.1 Ma. The dikes are strained within the STDS, indicating that final displacement along the STDS must post-date 22 Ma, yet be older than 18.4 Ma, the cooling age of muscovite in the shear zone. It is proposed that the exhumation of the Changgo culmination is related to tectonically driven erosion in response to crustal thickening and rebuilding of the orogenic critical taper wedge. Subsequently, deformation in the wedge migrated toward the foreland, expanding the orogenic wedge laterally and moving the locus of displacement from the Main Central thrust structurally downward to the Main Boundary thrust. [ABSTRACT FROM AUTHOR]