191 research outputs found
Production technology of Nabataean painted pottery compared with that of Roman terra sigillata
The Nabataeans, who founded the city of Petra (southern Jordan) in the late first millennium BCE, are noted for the production of a distinctive very fine pottery with painted decoration and a wall thickness sometimes as little as 1.5 mm; this pottery appears largely locally made and not widely circulated. Using a combination of OM, SEM with attached EDS, surface XRF, and XRD, it is shown that the Nabataean fine pottery bodies were produced using semi-calcareous clays which were fired to temperatures of about 950 °C. In contrast, published data indicate that contemporary and in many ways apparently functionally equivalent Roman terra sigillata, which was traded throughout the Roman Empire, was produced using fully-calcareous clays which were fired to temperatures in the range 1000–1100 °C. Furthermore, the high gloss slip applied to Roman terra sigillata is fully vitrified whereas the red-painted decoration applied to the Nabataean pottery is unvitrified. The more robust Roman terra sigillata is therefore better suited as tableware for serving and consuming food than would be the case for Nabataean fine pottery, and would be a more successful export material
Recruitment of older adults to three preventative lifestyle improvement studies
YesBackground: Recruiting isolated older adults to clinical trials is complex, time-consuming and difficult. Previous
studies have suggested querying existing databases to identify appropriate potential participants. We aim to
compare recruitment techniques (general practitioner (GP) mail-outs, community engagement and clinician
referrals) used in three randomised controlled trial (RCT) studies assessing the feasibility or effectiveness of
two preventative interventions in isolated older adults (the Lifestyle Matters and Putting Life In Years interventions).
Methods: During the three studies (the Lifestyle Matters feasibility study, the Lifestyle Matters RCT, the Putting Life In
Years RCT) data were collected about how participants were recruited. The number of letters sent by GP surgeries for
each study was recorded. In the Lifestyle Matters RCT, we qualitatively interviewed participants and intervention facilitators
at 6 months post randomisation to seek their thoughts on the recruitment process.
Results: Referrals were planned to be the main source of recruitment in the Lifestyle Matters feasibility study, but due to
a lack of engagement from district nurses, community engagement was the main source of recruitment. District nurse
referrals and community engagement were also utilised in the Lifestyle Matters and Putting Life In Years RCTs; both
mechanisms yielded few participants. GP mail-outs were the main source of recruitment in both the RCTs, but of those
contacted, recruiting yield was low (< 3%). Facilitators of the Lifestyle Matters intervention questioned whether the most
appropriate individuals had been recruited. Participants recommended that direct contact with health professionals
would be the most beneficial way to recruit.
Conclusions: Recruitment to the Lifestyle Matters RCT did not mirror recruitment to the feasibility study of the same
intervention. Direct district nurse referrals were not effective at recruiting participants. The majority of participants were
recruited via GP mail-outs, which may have led to isolated individuals not being recruited to the trials. Further research
is required into alternative recruitment techniques, including respondent-driven sampling plus mechanisms which will
promote health care professionals to recruit vulnerable populations to research.The Lifestyle Matters RCT was funded by the Medical Research Council (grant number G1001406); Sheffield Health and Social Research Consortium; National Institute for Health Research Public Health Research programme (project number 09/ 3004/01
20/20 Vision - What does the next 20 years hold for citizenship education?
Citizenship is a feeling, status and practice. It is essentially about living together and working to transform society towards greater democracy and social justice. It is a curriculum space shared by educational movements for human rights, political literacy, sustainable development, peace and equalities. Implementing this synthesis of politics, philosophy, sociology, law and international relations is an adventure in curriculum development. I identify three periods of Citizenship in England, analysing opportunities and significant and severe threats now and in the future
A putative relay circuit providing low-threshold mechanoreceptive input to lamina I projection neurons via vertical cells in lamina II of the rat dorsal horn
Background:
Lamina I projection neurons respond to painful stimuli, and some are also activated by touch or hair movement. Neuropathic pain resulting from peripheral nerve damage is often associated with tactile allodynia (touch-evoked pain), and this may result from increased responsiveness of lamina I projection neurons to non-noxious mechanical stimuli. It is thought that polysynaptic pathways involving excitatory interneurons can transmit tactile inputs to lamina I projection neurons, but that these are normally suppressed by inhibitory interneurons. Vertical cells in lamina II provide a potential route through which tactile stimuli can activate lamina I projection neurons, since their dendrites extend into the region where tactile afferents terminate, while their axons can innervate the projection cells. The aim of this study was to determine whether vertical cell dendrites were contacted by the central terminals of low-threshold mechanoreceptive primary afferents.
Results:
We initially demonstrated contacts between dendritic spines of vertical cells that had been recorded in spinal cord slices and axonal boutons containing the vesicular glutamate transporter 1 (VGLUT1), which is expressed by myelinated low-threshold mechanoreceptive afferents. To confirm that the VGLUT1 boutons included primary afferents, we then examined vertical cells recorded in rats that had received injections of cholera toxin B subunit (CTb) into the sciatic nerve. We found that over half of the VGLUT1 boutons contacting the vertical cells were CTb-immunoreactive, indicating that they were of primary afferent origin.
Conclusions:
These results show that vertical cell dendritic spines are frequently contacted by the central terminals of myelinated low-threshold mechanoreceptive afferents. Since dendritic spines are associated with excitatory synapses, it is likely that most of these contacts were synaptic. Vertical cells in lamina II are therefore a potential route through which tactile afferents can activate lamina I projection neurons, and this pathway could play a role in tactile allodynia
Effects of peripheral nerve injury on parvalbumin expression in adult rat dorsal root ganglion neurons
Background: Parvalbumin (PV) is a calcium binding protein that identifies a subpopulation of proprioceptive dorsal root ganglion (DRG) neurons. Calcitonin gene-related peptide (CGRP) is also expressed in a high proportion of muscle afferents but its relationship to PV is unclear. Little is known of the phenotypic responses of muscle afferents to nerve injury. Sciatic nerve axotomy or L5 spinal nerve ligation and section (SNL) lesions were used to explore these issues in adult rats using immunocytochemistry. Results: In naive animals, the mean PV expression was 25 % of L4 or L5 dorsal root ganglion (DRG) neurons, and this was unchanged 2 weeks after sciatic nerve axotomy. Colocalization studies with the injury marker activating transcription factor 3 (ATF3) showed that approximately 24 % of PV neurons expressed ATF3 after sciatic nerve axotomy suggesting that PV may show a phenotypic switch from injured to uninjured neurons. This possibility was further assessed using the spinal nerve ligation (SNL) injury model where injured and uninjured neurons are located in different DRGs. Two weeks after L5 SNL there was no change in total PV staining and essentially all L5 PV neurons expressed ATF3. Additionally, there was no increase in PV-ir in the adjacent uninjured L4 DRG cells. Co-labelling of DRG neurons revealed that less than 2 % of PV neurons normally expressed CGRP and no colocalization was seen after injury. Conclusion: These experiments clearly show that axotomy does not produce down regulation of PV protein in the DRG. Moreover, this lack of change is not due to a phenotypic switch in PV immunoreactive (ir) neurons, or de novo expression of PV-ir in uninjured neurons after nerve injury. These results further illustrate differences that occur when muscle afferents are injured as compared to cutaneous afferents
Validity of the International Physical Activity Questionnaire Short Form (IPAQ-SF) as a measure of physical activity (PA) in young people with cerebral palsy
Clinical trial registration number ISRCTN90378161.© 2019 The Authors. Published by Elsevier Ltd on behalf of Chartered Society of Physiotherapy. Objectives
The aim of this study was to examine the validity of the International Physical Activity Questionnaire Short Form (IPAQ-SF) as a measure of physical activity (PA) in young people with cerebral palsy (CP).
Design
Cross-sectional.
Setting
Participants were recruited through 8 National Health Service (NHS) trusts, one school, one university and through organisations that provide services for people with disabilities in England.
Participants
Sixty-four, ambulatory young people aged 10-19 years with CP [Gross Motor Function Classification System (GMFCS) levels I–III] participated in this study.
Main outcome measure
The IPAQ-SF was administered to participants. Participants were then asked to wear a wGT3X-BT triaxial accelerometer (ActiGraph, Pensacola, FL) for 7 days to objectively assess PA. Time spent in sedentary behaviour, in moderate to vigorous PA (MVPA) and in total PA (TPA) was compared between measures.
Results
Young people with CP self-reported less time in sedentary behaviour and underestimated the time spent in TPA,when compared to accelerometer measurements. Bland-Altman plots demonstrated poor agreement between the measures for MVPA, with upper and lower 95% limits of agreement of -147.23 to 148.9 min. After adjusting for gender and GMFCS level, age was a predictor of the difference between measures for MVPA (p < 0.001) and TPA (p < 0.001).
Conclusions
These findings suggest that the IPAQ-SF is not a valid method of measuring TPA or sedentary behaviour in young people with CP andit is not appropriate for use when assessing an individual’s time in MVPA. Therefore, where feasible, an objective measure of PA should be used
The investigation and provenance of glass vessel fragments attributed to the tomb of Amenhotep II, KV35, Valley of the Kings
Four polychrome glass fragments, excavated from tomb KV35 in the Valley of the Kings,
attributed to Amenhotep II, were analysed to further investigate the composition and
provenance of early Late Bronze Age glasses. An additional fragment, EA64163, cited by the British Museum as being stylistically analogous to the fragments from KV35, although with a findspot simply recorded as "Thebes", was also analysed. LA-ICP-MS analysis was used to
analyse multiple colours on the fragments to determine the major element composition, the
colouring strategies and establish provenance using trace element analysis. The resulting data
obtained was compared with four polychrome fragments of standard LBA Egyptian
composition, excavated from the palace of Amenhotep III at Malkata, previously analysed by
SEM-WDS. Analysis showed that the glasses excavated from KV35 are standard LBA glass
of Egyptian composition and were most likely produced in Egypt in the 18th Dynasty. The
fragment EA64163 is a low magnesia, low potash glass, comparable with Iron Age
composition, therefore should be reconsidered as a later glass. The analysis of glasses,
excavated from a reliable, early Egyptian context supports the proposition that glass
technology for multiple colours was established in Egypt at least as early as 1400 BCE
Critical assessment of the elemental composition of Corning archeological reference glasses by LA-ICP-MS
Corning archeological reference glasses A, B, C, and D have been made to simulate different historic technologies of glass production and are used as standards in historic glass investigations. In this work, nanoseconds (193, 266 nm) and femtosecond (800 nm) laser ablation were used to study the elemental composition of Corning glasses using laser ablation inductively coupled plasma mass spectrometry. The determined concentrations of 26 oxides (Li2O, B2O3, Na2O, MgO, Al2O3, SiO2, P2O5, K2O, CaO, TiO2, V2O5, Cr2O3, MnO, Fe2O3, CoO, NiO, CuO, ZnO, Rb2O, SrO, ZrO2, SnO2, Sb2O5, BaO, PbO, Bi2O3) are compared with values reported in the literature. Results show variable discrepancies between the data, with the largest differences found for Cr2O3 in Corning A; Li2O, B2O3, and Cr2O3 in Corning B; and MnO, Sb2O5, Cr2O3, and Bi2O3 in Corning C. The best agreement between the measured and literature values was found for Corning D. However, even for this reference, glass re-evaluation of the data was necessary and new values for PbO, BaO, and Bi2O3 are proposed
How do MNC R&D laboratory roles affect employee international assignments?
Research and development (R&D) employees are important human resources for multinational corporations (MNCs) as they are the driving force behind the advancement of innovative ideas and products. International assignments of these employees can be a unique way to upgrade their expertise; allowing them to effectively recombine their unique human resources to progress existing knowledge and advance new ones. This study aims to investigate the effect of the roles of R&D laboratories in which these employees work on the international assignments they undertake. We categorise R&D laboratory roles into those of the support laboratory, the locally integrated laboratory and the internationally interdependent laboratory. Based on the theory of resource recombinations, we hypothesise that R&D employees in support laboratories are not likely to assume international assignments, whereas those in locally integrated and internationally interdependent laboratories are likely to assume international assignments. The empirical evidence, which draws from research conducted on 559 professionals in 66 MNC subsidiaries based in Greece, provides support to our hypotheses. The resource recombinations theory that extends the resource based view can effectively illuminate the international assignment field. Also, research may provide more emphasis on the close work context of R&D scientists rather than analyse their demographic characteristics, the latter being the focus of scholarly practice hitherto
Neuronal circuitry for pain processing in the dorsal horn
Neurons in the spinal dorsal horn process sensory information, which is then transmitted to several brain regions, including those responsible for pain perception. The dorsal horn provides numerous potential targets for the development of novel analgesics and is thought to undergo changes that contribute to the exaggerated pain felt after nerve injury and inflammation. Despite its obvious importance, we still know little about the neuronal circuits that process sensory information, mainly because of the heterogeneity of the various neuronal components that make up these circuits. Recent studies have begun to shed light on the neuronal organization and circuitry of this complex region
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