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Understanding the retention mechanism of U by amorphous silica (i.e., opal) in the environment is of great importance to nuclear-waste disposal because opals can retain U for millions of years. Uraniferous opals from Spor Mountain and the Thomas Range, Utah, U.S.A., are examined in terms of their mineralogical, chemical, and isotopic compositions. Uranium-rich zones composed of most likely vorlanite, CaUO4, occur in fibrous opal-CT (termed lussatite) along the interface of the phase with microcrystalline quartz. Red- to black-colored precipitates of vorlanite also occur in the interstices between fibers and grains in lussatite and massy opals, respectively. The high abundance of vorlanite in certain growth zones can be explained by the diffusion of Ca and U along boundaries of layers, grains, and fibers and by the release of Ca and U through the transformation of opal-A into opal-CT and from opal-CT into microcrystalline quartz. Similar O-isotope compositions of opal-CT and associated microcrystalline quartz indicate that crystallization processes and deposition of subsequent layers of opal occurred from fluids of similar origin and T Differences in the isotope and chemical composition between uraniferous opals/microcrystalline quartz, the SiO2 polymorph moganite, and pyrolusite indicate the past occurrence of various alteration processes involving fluids of different composition and T. The results of this study indicate that assemblages of opal and microcrystalline quartz can retain U for millions of years as long as confined pore spaces between different generations of opal and quartz or between growth features of opal provide space for the nucleation and adsorption of U-bearing phases and species.

Storm-generated event beds are an important source of paleoecological information, especially in Paleozoic strata. Storm deposition and subsequent physical and biological modification can potentially alter the diversity structure of death assemblages significantly. To examine the effects of storm deposition on fossil assemblage composition, storm beds are compared with co-occurring beds representing background sedimentation in 67 samples from six Ordovician mixed carbonate-clastic units deposited above the maximum storm wave base. In the great majority of pairwise comparisons, evenness and sampled richness are higher in storm beds than in background beds. This effect is not explained by differences in lithification, skeletal fragmentation, or in the proportions of aragonitic or multielement skeletons. The elevated diversity of storm beds can result from homogenization of fine-scale faunal patchiness preserved in background beds or may be due to taphonomic feedback. The relative importance of these two end-member scenarios can be evaluated with detrended correspondence analysis. In shallow, carbonate-dominated environments, the former appears to predominate, while the latter is more important in a deeper setting dominated by fine-grained clastics. The disparity between background beds and storm beds suggests that, at least in the Lower Paleozoic, background beds may record a higher-resolution paleoecological signal while storm beds record a more complete census of alpha diversity. Because post–Middle Ordovician increases in the depth and intensity of bioturbation may have diminished the temporal resolution and increase the faunal completeness of background beds, this disparity is not necessarily expected in younger strata.

Relative abundance data are of primary importance in paleoecology, but it is not always obvious how they should be interpreted. Because relative abundance is expressed as a proportion of the total sample, change in the abundance of one group necessarily changes the relative abundance of all groups in the sample. There are two possible interpretations for a trend in the relative abundance of a taxon: an “active” scenario in which the trend reflects change in the population density of the group itself, or a “passive” scenario in which the change is driven by population changes in other taxa. To discriminate between these scenarios it is necessary to collect absolute abundance data (abundance expressed as a function of sample area or volume). We examine both absolute and relative abundance trends through a major paleoecological transition: the shift from trilobite-dominated to brachiopod-dominated paleocommunities in shallow marine carbonates spanning the Lower/Middle Ordovician boundary in western Utah and eastern Nevada. We sampled 61 carbonate mudstone and wackestone beds from the upper Ibex Series (Lower Ordovician) and lower Whiterock Series (Middle Ordovician) at three sections that span the boundary. All samples come from the shallow subtidal Bathyurid trilobite biofacies. Samples were broken into small pieces, and all skeletal fragments >2 mm were identified to the finest possible taxonomic level. Consistent with previous work on this interval, the relative abundance of trilobites declines sharply across the boundary, while the relative abundance of brachiopods increases. Absolute abundance data indicate that the decline in trilobite abundance is genuine and not an artifact of normalization. The trend is not easily explained by sampling bias, facies distribution, taphonomic regime, or sedimentation style. The dramatic shift in abundance contrasts with relatively minor changes in relative genus richness across the boundary. This is partly ascribable to differences in the relative abundance structure of trilobite faunas. Though comparable numbers of trilobite and brachiopod genera occur above and below the boundary, the trilobite fauna from the upper Ibex Series has lower evenness then the lower Whiterock Series fauna. Hence sampled trilobite richness is high in the lower Whiterock despite the small number of specimens. This highlights the importance of collecting abundance data. Although these data suggest that in at least some cases richness and abundance patterns are not closely coupled, more robust richness data are necessary to confirm this conclusion.

A polyphagous insect herbivore has a wide range of host plants. However, it has been found that many polyphagous herbivores commonly exhibit a strong preference for a subset of species in their broad host range, and various host biotypes exist in herbivore populations. Nutrition and secondary metabolites in plants affect herbivore preference and performance, but it is still not clear which factors determine the host range and host preference of polyphagous herbivores. Cotton-melon aphids, Glover, collected from cotton and cucumber crops, were used in this study. The genetic backgrounds of these aphids were detected using microsatellite PCR and six genotypes were evaluated. Performance of these six aphid genotypes on excised leaves and plants of cotton and cucumber seedlings were examined through a reciprocal transplant experiment. In order to detect whether the feeding experience on artificial diet would alter aphid host range, the six genotypes of aphids fed on artificial diet for seven days were transferred onto cotton and cucumber leaves, and then their population growth on these two host plants was surveyed. Aphids from cotton and cucumber plants could not colonize the excised leaves and intact plants of cucumber and cotton seedlings, respectively. All six genotypes of aphids collected from cotton and cucumber plants could survive and produce offspring on artificial diet, which lacked plant secondary metabolites. The feeding experience on the artificial diet did not alter the ability of all six genotypes to use their native host plants. However, after feeding on this artificial diet for seven days, two aphid genotypes from cotton and one from cucumber acquired the ability to use both of the excised leaves from cucumber and cotton plants. The two aphid genotypes from cotton conditioned by the feeding experience on artificial diet and then reared on excised cucumber leaves for >12 generations still maintained the ability to use intact cotton plants but did not establish a population on cucumber plants. However, one cucumber genotype conditioned by artificial diet and then reared on excised cotton leaves could use both the intact cotton and cucumber plants, showing that the expansion of host range was mediated by feeding experience. Feeding experience on artificial diet induced the expansion of host range of the cucurbit-specialized , and this expansion was genotype-specific. We speculated that feeding on a constant set of host plants in the life cycle of aphids may contribute to the formation of host specialization.

The application of drones, also known as unmanned aerial vehicles deployed as unmanned aerial base stations (UABSs), has received extensive interest for public safety communications (PSC) to fill the coverage gaps and establish ubiquitous connectivity. In this article, we design a PSC LTE-Advanced air–ground-based HetNet (AG-HetNet) that is a scenario representation of a geographical area during and after a disaster. As part of the AG-HetNet infrastructure, we have UABSs and ground user equipment (GUE) flocking together in clusters at safe places or evacuation shelters. AG-HetNet uses cell range expansion (CRE), intercell interference coordination (ICIC), and 3D beamforming techniques to ensure ubiquitous connectivity. Through system-level simulations and using a brute-force technique, we evaluate the performance of the AG-HetNet in terms of fifth-percentile spectral efficiency (5pSE) and coverage probability. We compare system-wide 5pSE and coverage probability when UABSs are deployed on a hexagonal grid and for different clustering distributions of GUEs. The results show that reduced power subframes (FeICIC) defined in 3GPP Release-11 can provide practical gains in 5pSE and coverage probability than the 3GPP Release-10 with almost blank subframes (eICIC).

The Ober and Thomas tests are subjective and involve a \"negative\" or \"positive\" assessment, making them difficult to apply within the paradigm of evidence-based medicine. No authors have combined the subjective clinical assessment with an objective measurement for these special tests. To compare the subjective assessment of iliotibial band and iliopsoas flexibility with the objective measurement of a digital inclinometer, to establish normative values, and to provide an evidence-based critical criterion for determining tissue tightness. Cross-sectional study. Clinical research laboratory. Three hundred recreational athletes (125 men, 175 women; 250 in injured group, 50 in control group). Iliotibial band and iliopsoas muscle flexibility were determined subjectively using the modified Ober and Thomas tests, respectively. Using a digital inclinometer, we objectively measured limb position. Interrater reliability for the subjective assessment was compared between 2 clinicians for a random sample of 100 injured participants, who were classified subjectively as either negative or positive for iliotibial band and iliopsoas tightness. Percentage of agreement indicated interrater reliability for the subjective assessment. For iliotibial band flexibility, the average inclinometer angle was -24.59 degrees +/- 7.27 degrees . A total of 432 limbs were subjectively assessed as negative (-27.13 degrees +/- 5.53 degrees ) and 168 as positive (-16.29 degrees +/- 6.87 degrees ). For iliopsoas flexibility, the average inclinometer angle was -10.60 degrees +/- 9.61 degrees . A total of 392 limbs were subjectively assessed as negative (-15.51 degrees +/- 5.82 degrees ) and 208 as positive (0.34 degrees +/- 7.00 degrees ). The critical criteria for iliotibial band and iliopsoas flexibility were determined to be -23.16 degrees and -9.69 degrees , respectively. Between-clinicians agreement was very good, ranging from 95.0% to 97.6% for the Thomas and Ober tests, respectively. Subjective assessments and instrumented measurements were combined to establish normative values and critical criterions for tissue flexibility for the modified Ober and Thomas tests.

Translating extra-linguistic culture-bound concepts in Mofolo presents a daunting challenge to literary translators as such concepts require that the translator possess a substantial amount of knowledge and background of the Sesotho culture. The present study undertakes a comparative analysis of Thomas Mofolo's Moeti oa Bochabela and its translations Traveller to the East (English) and L'homme qui marchait vers le soleil levant (French) to highlight problems encountered due to lack of understanding of culture-bound extra-linguistic elements (ECE). The article also aims to bring to light translation techniques employed and culture related factors that may hinder the translator from rendering the intended meaning with high accuracy. The semantic analysis of culture-bound extra-linguistic elements shows how readers of the English and French translation may not have a full grasp of the book due to lack of functional equivalence and the disparity in semantic range between Sesotho and the European languages. The impasse of meaning is evidenced throughout the book by the number of words that were either left untranslated or mistranslated as can be observed in the translation of the two poems addressed to Fekisi's cows. The paper uses some of the untranslated and mistranslated elements to show that there is no such a thing as an absolute translation.

To establish a normative range of values for muscle length in the hamstrings, iliopsoas, rectus femoris, and gastrocnemius muscles of college-age students. Cross sectional descriptive study. University research laboratory. Seventy-two healthy college students participated in the study, forty-seven females and twenty-five males. Bilateral muscle length measurements of the gastrocnemius, hamstring, rectus femoris and iliopsoas muscles were obtained using a standard goniometer. The assessment techniques included: the prone, figure four position with active dorsiflexion for the gastrocnemius, the active knee extension test (AKE) for hamstrings, the modified Thomas test for rectus femoris, and the Thomas test for iliopsoas. Normative resting muscle length values were calculated from the group mean for each muscle, using goniometric measurements. Inferential statistics revealed significant differences between right and left sides for hamstring, rectus femoris and gastrocnemius muscles ( p⩽0.05). Between group comparisons revealed hamstring length for females being more flexible than males ( p⩽0.05). These data provide the clinician with a normative value for lower extremity flexibility in the college-age student. Normative values may be used to identify patients at risk for injury due to decreased flexibility and guide interventions to address these deficits.

The article examines, in two different moments, the major sociological approaches to science in the twentieth century: the Sociology of Knowledge, the Sociology of Science and the Sociology of Scientific Knowledge. In the first topic, Karl Mannheim's and Robert King Merton's sociological arguments are summarized. We support that the interpretation of Mannheim's work must be recognized as an epistemological prerequisite to the development of Merton's Sociology of Science. Adapted by Merton, Mannheim's sociological metatheory appears in Merton through a functional structuralism approach, associated with a middle range theory. In the second moment, we summarize Thomas Kuhn's arguments for, subsequently, examining the Sociology of Scientific Knowledge as a constructive appreciation to mertonian tradition of thought. The study of the logic principles of David Bloor's Sociology of Scientific Knowledge as well as the investigation of the tradition of thought started in University of Edinburgh, Scotland, was the elementary focus of this topic. Finally, the major characteristics of each tradition are elucidated, searching for changes and continuities that enable the development of the sociological approach on scientific activity since its classical genesis until the contemporary studies. Adapted from the source document.

Focusing on the Magnificat áã in Monteverdi's 1610 publication, this article repudiates the recently repeated proposal by Roger Bowers that its high-def notation demands transposition down a mere 2nd (for which there is no known contemporary precedent); 100 clear instances of transposition by the conventional 4th (and 5th) are listed. Besides its implausible resultant 'F minor', the narrower transposition cannot be justified on the basis of perceived ' inconsistencies' of range, as Monteverdi's own music (and others') provides ample evidence of lower vocal scoring than is expected today.