Luminescence dating of sediments from Underhoull and Lund, Unst, Shetland

This report concerns optically stimulated luminescence (OSL) investigations of sediments from the the foreshore at Burga Sands, Underhoull, and a dune section at Lund, in south-west Unst (Shetland). Samples were collected in February 2016 to establish the timing of sand accumulation, adding to an expanding set of dated sand blows in the Northern Isles and Scotland. The resulting chronologies define the local environmental record of sand movements in the vicinity of Underhoull and Lund, with their adjacent Norse longhouses and chapel. The sediment stratigraphies on the foreshore of Burga Sands were explored through four profiles, comprising the natural accumulations adjacent to two noosts (profiles 1 and 2), and the substrate sequences immediately beneath the noosts (P3&4). The dune section at Lund was explored in a single profile (P5). This report describes the progression from fieldwork and sampling, through initial luminescence screening measurements made with the portable OSL reader (on 45 samples), to subsequent calibrated analysis in the laboratory, first, to characterise the OSL and IRSL signals from each sample, then by targeted quantitative OSL dating on a further set of 10 samples. The ‘field profiles’ provided the first indication that the substrate stratigraphies at Underhoull, extend from the late glacial period to the modern day. The maxima and dynamic ranges in signal intensities for the sequences beneath the noosts, suggest that the construction and modification of these structures were temporally distinct. For the Lund section, the range in signal intensities through these sediments, indicate a shorter chronology, which was confirmed by subsequent characterisation of the profiling samples in the laboratory. The following chronology was obtained for the Underhoull section: 1) onset of sand activity, as recorded in the sedimentary archives of profiles 1 and 2, at 3.22 ± 0.29 ka (1210 ± 290BC; SUTL2861) and 1.99 ± 0.15 ka (AD30 ± 150; SUTL2863) 2) modification and re-build of the first noost at 0.48 ± 0.06 ka (AD1540 ± 60; SUTL2866) 3) construction of the second noost at 0.81 ± 0.07 ka (AD1210 ± 70; SUTL2867) 4) continued sand movements into the early 20th century AD (0.12 ± 0.06 ka; AD1900 ± 60; SUTL2862), with arguably heightened activity at the onset of the Little Ice Age (0.64 ± 0.10 ka; AD 1380 ± 60; SUTL2866). For the Lund dune section, the sediment chronology spans from the early 14th century AD through to the early 18th century AD (0.70 ± 0.05 ka; SUTL2868, through 0.52 ± 0.04 ka; SUTL2869, to 0.31 ± 0.02 ka; SUTL2870), corresponding with the onset and waning stages of the Little Ice Age. The chronology presented here is consistent with an emerging regional framework of sand movements in the Northern Isles and Scotland, with activity in the Neolithic, Early and Late Bronze Ages, the Iron Age, the Viking/Medieval period, and Little Ice Age. The Underhoull section dated here provides a broad chronology for sand blow and, importantly, places sediments underneath two noosts into the late Norse/ Mediaeval period. The dune section dates a high resolution local record within the last 700 years. Opportunities to extend the high resolution palaeoenvironmental record were identified in the adjacent land and dune-scape, and especially in the palaeo-loch landward of the Lund section, which has received sand in the past

Neurospora crassa suppressors act on amber

Neurospora crassa suppressors act on ambe

Developments in MRI-targeted prostate biopsy

PURPOSE OF REVIEW: MRI-targeted prostate biopsy may be an attractive alternative to systematic biopsy for diagnosing clinically significant prostate cancer. In this narrative review, we discuss the new developments that have occurred in the advancement of MRI-targeted prostate biopsy, over the past 24 months. RECENT FINDINGS: MRI-targeted biopsy offers enhanced diagnostic accuracy, when compared with the current standard of care of systematic transrectal ultrasound-guided (TRUS) biopsy, by decreasing the overall number of biopsies needed, maintaining or improving significant prostate cancer detection, and reducing the detection of clinically insignificant prostate cancer. The necessity of combining systematic prostate biopsy with MRI-targeted biopsy is still debated. The use of MRI--ultrasound fusion systems for lesion-targeting is promising for optimizing significant cancer detection, but recent evidence suggests that additional cognitive biopsy cores are still useful in detecting additional cancers. SUMMARY: MRI-targeted biopsy in selected men with positive MRI offers a number of benefits over systematic biopsy in all men, and as such, may emerge as the new standard of care for the diagnosis of clinically significant prostate cancer

Functional Imaging of Human Vestibular Cortex Activity Elicited by Skull Tap and Auditory Tone Burst

The current study characterizes brain activation in response to two modes of vestibular stimulation: skull tap and auditory tone burst. The auditory tone burst has been used in previous studies to elicit either the vestibulo-spinal reflex (saccular-mediated colic Vestibular Evoked Myogenic Potentials (cVEMP)), or the ocular muscle response (utricle-mediated ocular VEMP (oVEMP)). Some researchers have reported that air-conducted skull tap elicits both saccular and utricle-mediated VEMPs, while being faster and less irritating for the subjects. However, it is not clear whether the skull tap and auditory tone burst elicit the same pattern of cortical activity. Both forms of stimulation target the otolith response, which provides a measurement of vestibular function independent from semicircular canals. This is of high importance for studying otolith-specific deficits, including gait and balance problems that astronauts experience upon returning to earth. Previous imaging studies have documented activity in the anterior and posterior insula, superior temporal gyrus, inferior parietal lobule, inferior frontal gyrus, and the anterior cingulate cortex in response to different modes of vestibular stimulation. Here we hypothesized that skull taps elicit similar patterns of cortical activity as the auditory tone bursts, and previous vestibular imaging studies. Subjects wore bilateral MR compatible skull tappers and headphones inside the 3T GE scanner, while lying in the supine position, with eyes closed. Subjects received both forms of the stimulation in a counterbalanced fashion. Pneumatically powered skull tappers were placed bilaterally on the cheekbones. The vibration of the cheekbone was transmitted to the vestibular system, resulting in the vestibular cortical response. Auditory tone bursts were also delivered for comparison. To validate our stimulation method, we measured the ocular VEMP outside of the scanner. This measurement showed that both skull tap and auditory tone burst elicited vestibular evoked myogenic potentials, indicated by eye muscle responses. We further assessed subjects' postural control and its correlation with vestibular cortical activity. Our results provide the first evidence of using skull taps to elicit vestibular activity inside the MRI scanner. By conducting conjunction analyses we showed that skull taps elicit the same activation pattern as auditory tone bursts (superior temporal gyrus), and both modes of stimulation activate previously identified vestibular cortical regions. Additionally, we found that skull taps elicit more robust vestibular activity compared to auditory tone bursts, with less reported aversive effects. This further supports that the skull tap could replace auditory tone burst stimulation in clinical interventions and basic science research. Moreover, we observed that greater vestibular activation is associated with better balance control. We showed that not only the quality of balance (indicated by the amount of body sway) but also the ability to maintain balance for a longer time (indicated by the balance time) was associated with individuals' vestibular cortical excitability. Our findings support an association between vestibular cortical activity and individual differences in balance. In sum, we found that the skull tap stimulation results in activation of canonical vestibular cortex, suggesting an equally valid, but more tolerable stimulation method compared to auditory tone bursts. This is of high importance in longitudinal vestibular assessments, in which minimizing aversive effects may contribute to higher protocol adherence

The effects of attractive vs. repulsive instructional cuing on balance performance

Abstract Background Torso-based vibrotactile feedback has been shown to improve postural performance during quiet and perturbed stance in healthy young and older adults and individuals with balance impairments. These systems typically include tactors distributed around the torso that are activated when body motion exceeds a predefined threshold. Users are instructed to “move away from the vibration”. However, recent studies have shown that in the absence of instructions, vibrotactile stimulation induces small (~1°) non-volitional responses in the direction of its application location. It was hypothesized that an attractive cuing strategy (i.e., “move toward the vibration”) could improve postural performance by leveraging this natural tendency. Findings Eight healthy older adults participated in two non-consecutive days of computerized dynamic posturography testing while wearing a vibrotactile feedback system comprised of an inertial measurement unit and four tactors that were activated in pairs when body motion exceeded 1° anteriorly or posteriorly. A crossover design was used. On each day participants performed 24 repetitions of Sensory Organization Test condition 5 (SOT5), three repetitions each of SOT 1–6, three repetitions of the Motor Control Test, and five repetitions of the Adaptation Test. Performance metrics included A/P RMS, Time-in-zone and 95 % CI Ellipse. Performance improved with both cuing strategies but participants performed better when using repulsive cues. However, the rate of improvement was greater for attractive versus repulsive cuing. Conclusions The results suggest that when the cutaneous signal is interpreted as an alarm, cognition overrides sensory information. Furthermore, although repulsive cues resulted in better performance, attractive cues may be as good, if not better, than repulsive cues following extended training.http://deepblue.lib.umich.edu/bitstream/2027.42/134532/1/12984_2016_Article_131.pd

Susceptibility to disease (tropical theileriosis) is associated with differential expression of host genes that possess motifs recognised by a pathogen DNA binding protein

BACKGROUND: Knowledge of factors that influence the outcome of infection are crucial for determining the risk of severe disease and requires the characterisation of pathogen-host interactions that have evolved to confer variable susceptibility to infection. Cattle infected by Theileria annulata show a wide range in disease severity. Native (Bos indicus) Sahiwal cattle are tolerant to infection, whereas exotic (Bos taurus) Holstein cattle are susceptible to acute disease. METHODOLOGY/PRINCIPAL FINDINGS: We used RNA-seq to assess whether Theileria infected cell lines from Sahiwal cattle display a different transcriptome profile compared to Holstein and screened for altered expression of parasite factors that could generate differences in host cell gene expression. Significant differences (<0.1 FDR) in the expression level of a large number (2211) of bovine genes were identified, with enrichment of genes associated with Type I IFN, cholesterol biosynthesis, oncogenesis and parasite infection. A screen for parasite factors found limited evidence for differential expression. However, the number and location of DNA motifs bound by the TashAT2 factor (TA20095) were found to differ between the genomes of B. indicus vs. B. taurus, and divergent motif patterns were identified in infection-associated genes differentially expressed between Sahiwal and Holstein infected cells. CONCLUSIONS/SIGNIFICANCE: We conclude that divergent pathogen-host molecular interactions that influence chromatin architecture of the infected cell are a major determinant in the generation of gene expression differences linked to disease susceptibility

Luminescence dating of soils and sediments from Jerash, Jordan

The urban site of Jerash, Jordan is recognised as one of the great cities of the classical Middle East and has been the subject of ongoing systematic archaeological investigations since the 1920s. Its significance lies in its location on limestone geology in one of the more fertile areas of the Ajlun Highlands in northern Jordan with a good water supply, a number of springs and its central position in regional trade routes. The hinterland context of the city is yet to be considered and is a significant omission given the importance of water and its management together with the agricultural systems dependent on water in supporting urban development. Landscape chronologies are vital to the establishment of city and hinterland relationships and in this working papers we assess the value and significance of optically stimulated luminescence (OSL) measurement in this endeavour. Our findings so far suggest a measurement cluster range of ca. 480 BC – 250 BC in landscapes underlying the city and a dominant trend of sediments infilling the adjacent Wadi Suf between 640 ± 240 AD and 1400 ± 60 AD reflecting land management changes in a soil environment sensitive to degradation

ApiAP2 factors as candidate regulators of stochastic commitment to merozoite production in Theileria annulata

The ability of vector-borne Apicomplexan parasites (Babesia, Plasmodium and Theileria) to change from one life-cycle stage to the next is critical for establishment of infection and transmission to new hosts. Stage differentiation steps of both Plasmodium and Theileria are known to involve stochastic transition through an intermediate form to a point that commits the cell to generate the next stage in the life-cycle. In this study we have identified genes encoding ApiAP2 DNA binding proteins in Theileria annulata that are differentially expressed during differentiation from the macroschizont stage, through merozoite production (merogony) to the piroplasm stage. The results provide evidence that the ApiAp2 factor in Theileria that possesses the orthologue of the Plasmodium AP2-G domain may also operate to regulate gametocytogenesis, and that progression to merogony is promoted by the ability of a merozoite DNA binding protein to preferentially up-regulate its own production. In addition, identification of multiple ApiAP2 DNA binding domains that bind related motifs within and across vector-borne Apicomplexan genera lead to the proposal that the mechanisms that promote the transition from asexual to sexual replication will show a degree of conservation