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Reading Interests and Preferences of Indian, Black, and White High School Students
The problem of this study is the identification of differences in reading interests and preferences of Indian, Black, and white adolescents of both sexes and from different high school grade levels as they are related to (a) educational background of the parents, (b) availability of reading materials, (c) community size, and (d) the extent to which these preferences are represented in the standard selection aids for secondary school reading materials. A reading interest inventory was administered in the fall term, 1972, through English classes in twenty integrated schools in Oklahoma, representing three levels of population concentration. Community resources in reading materials available through school libraries, public libraries, and bookstores were evaluated. The reading inventories of 3,581 students were chosen to be evaluated to determine if there were significant differences at the .05 level. Earlier studies have indicated that sex and age are major factors in determining what teenagers read about and that adolescents' reading interests tended to be unique, personal, and very unpredictable.- Few studies have been reported that involved ethnic origin or family levels of education
Clusterin levels are increased in Alzheimer's disease and influence the regional distribution of Aβ
Diasporic memory practice on the internet: remembering lost homelands
This article examines the work of two diasporic memory organizations, Kresy-Siberia and Houshamadyan, which have both developed Internet platforms to collect and share information about lost homelands: in the former case, the pre-World War II eastern borderlands of Poland; in the latter, the Armenian communities of the Ottoman Empire that were destroyed by genocide. The article draws on interviews undertaken with participants in order to examine the activism of these two diasporic memory groups and to analyze the relationship between memory practice and the online space. The article asks what difference the creation of an online platform makes to such groups, both for individuals and for the wider diaspora, and seeks to understand how the possibilities offered by these platforms shape diasporic practice. The article shows how, despite the apparent similarities between the online presences of these two organizations, their use of the Internet facilitates diverse forms of memory practice, which are influenced by the historically specific needs of participants in these different diasporic communities
Evaluation of sedation for standing clinical procedures in horses using detomidine combined with buprenorphine
Disruption of MEF2C signaling and loss of sarcomeric and mitochondrial integrity in cancer-induced skeletal muscle wasting
Cancer cachexia is a highly debilitating paraneoplastic disease observed in more than 50% of patients with advanced cancers and directly contributes to 20% of cancer deaths. Loss of skeletal muscle is a defining characteristic of patients with cancer cachexia and is associated with poor survival. The present study reveals the involvement of a myogenic transcription factor Myocyte Enhancer Factor (MEF) 2C in cancer-induced skeletal muscle wasting. Increased skeletal muscle mRNA expression of Suppressor of Cytokine Signaling (Socs) 3 and the IL-6 receptor indicative of active IL-6 signaling was seen in skeletal muscle of mice bearing the Colon 26 (C26) carcinoma. Loss of skeletal muscle structural integrity and distorted mitochondria were also observed using electron microscopy. Gene and protein expression of MEF2C was significantly downregulated in skeletal muscle from C26-bearing mice. MEF2C gene targets myozenin and myoglobin as well as myokinase were also altered during cachexia, suggesting dysregulated oxygen transport capacity and ATP regeneration in addition to distorted structural integrity. In addition, reduced expression of calcineurin was observed which suggested a potential pathway of MEF2C dysregulation. Together, these effects may limit sarcomeric contractile ability and also predispose skeletal muscle to structural instability; associated with muscle wasting and fatigue in cachexia
Intra-individual metameric variation expressed at the enamel-dentine junction of lower post-canine dentition of South African fossil hominins and modern humans
Objectives
The aim of this study is to compare the degree and patterning of inter‐ and intra‐individual metameric variation in South African australopiths, early Homo and modern humans. Metameric variation likely reflects developmental and taxonomical issues, and could also be used to infer ecological and functional adaptations. However, its patterning along the early hominin postcanine dentition, particularly among South African fossil hominins, remains unexplored.
Materials and Methods
Using microfocus X‐ray computed tomography (µXCT) and geometric morphometric tools, we studied the enamel‐dentine junction (EDJ) morphology and we investigated the intra‐ and inter‐individual EDJ metameric variation among eight australopiths and two early Homo specimens from South Africa, as well as 32 modern humans.
Results
Along post‐canine dentition, shape changes between metameres represented by relative positions and height of dentine horns, outlines of the EDJ occlusal table are reported in modern and fossil taxa. Comparisons of EDJ mean shapes and multivariate analyses reveal substantial variation in the direction and magnitude of metameric shape changes among taxa, but some common trends can be found. In modern humans, both the direction and magnitude of metameric shape change show increased variability in M2‐M3 compared to M1‐M2. Fossil specimens are clustered together showing similar magnitudes of shape change. Along M2‐M3, the lengths of their metameric vectors are not as variable as those of modern humans, but they display considerable variability in the direction of shape change.
Conclusion
The distalward increase of metameric variation along the modern human molar row is consistent with the odontogenetic models of molar row structure (inhibitory cascade model). Though much remains to be tested, the variable trends and magnitudes in metamerism in fossil hominins reported here, together with differences in the scale of shape change between modern humans and fossil hominins may provide valuable information regarding functional morphology and developmental processes in fossil species
Entraining Movement-Related Brain Oscillations to Suppress Tics in Tourette Syndrome
Tourette syndrome (TS) is a neuropsychiatric disorder characterised by the occurrence of vocal and motor tics. Tics are involuntary, repetitive, movements and vocalisations that occur in bouts, typically many times in a single day, and are often preceded by a strong urge-to-tic - referred to as a premonitory urge (PU). TS is associated with: dysfunction within corticalstriatal-thalamic-cortical (CSTC) brain circuits implicated in the selection of movements; impaired operation of GABA signalling within the striatum; and hyper-excitability of cortical sensorimotor regions that may contribute to the occurrence of tics. Non-invasive brain stimulation delivered to cortical motor areas can: modulate cortical motor excitability; entrain brain oscillations; and reduce tics in TS. However, these techniques are not optimal for treatment outside of the clinic. We investigated whether rhythmic pulses of median nerve stimulation (MNS) could entrain brain oscillations linked to the suppression of movement, and influence the initiation of tics in TS. We demonstrate that pulse trains of rhythmic MNS, delivered at 12Hz, entrain sensorimotor Mu-band oscillations, while pulse trains of arrhythmic MNS do not. Furthermore, we demonstrate that while rhythmic Mu stimulation has statistically significant but small effects on the initiation of volitional movements, and no discernable effect on performance of an attentionally demanding cognitive task, it nonetheless leads to a large reduction in tic frequency and tic intensity in individuals with TS. This approach has considerable potential in our view to be developed into a therapeutic device suitable for use outside of the clinic to suppress tics and PU in TS
Evolution of the patellar sesamoid bone in mammals
The patella is a sesamoid bone located in the major extensor tendon of the knee joint, in the hindlimb of many tetrapods. Although numerous aspects of knee morphology are ancient and conserved among most tetrapods, the evolutionary occurrence of an ossified patella is highly variable. Among extant (crown clade) groups it is found in most birds, most lizards, the monotreme mammals and almost all placental mammals, but it is absent in most marsupial mammals as well as many reptiles. Here, we integrate data from the literature and first-hand studies of fossil and recent skeletal remains to reconstruct the evolution of the mammalian patella. We infer that bony patellae most likely evolved between four and six times in crown group Mammalia: in monotremes, in the extinct multituberculates, in one or more stem-mammal genera outside of therian or eutherian mammals and up to three times in therian mammals. Furthermore, an ossified patella was lost several times in mammals, not including those with absent hindlimbs: once or more in marsupials (with some re-acquisition) and at least once in bats. Our inferences about patellar evolution in mammals are reciprocally informed by the existence of several human genetic conditions in which the patella is either absent or severely reduced. Clearly, development of the patella is under close genomic control, although its responsiveness to its mechanical environment is also important (and perhaps variable among taxa). Where a bony patella is present it plays an important role in hindlimb function, especially in resisting gravity by providing an enhanced lever system for the knee joint. Yet the evolutionary origins, persistence and modifications of a patella in diverse groups with widely varying habits and habitats—from digging to running to aquatic, small or large body sizes, bipeds or quadrupeds—remain complex and perplexing, impeding a conclusive synthesis of form, function, development and genetics across mammalian evolution. This meta-analysis takes an initial step toward such a synthesis by collating available data and elucidating areas of promising future inquiry
Assessing Arboreal Adaptations of Bird Antecedents: Testing the Ecological Setting of the Origin of the Avian Flight Stroke
The origin of avian flight is a classic macroevolutionary transition with research spanning over a century. Two competing models explaining this locomotory transition have been discussed for decades: ground up versus trees down. Although it is impossible to directly test either of these theories, it is possible to test one of the requirements for the trees-down model, that of an arboreal paravian. We test for arboreality in non-avian theropods and early birds with comparisons to extant avian, mammalian, and reptilian scansors and climbers using a comprehensive set of morphological characters. Non-avian theropods, including the small, feathered deinonychosaurs, and Archaeopteryx, consistently and significantly cluster with fully terrestrial extant mammals and ground-based birds, such as ratites. Basal birds, more advanced than Archaeopteryx, cluster with extant perching ground-foraging birds. Evolutionary trends immediately prior to the origin of birds indicate skeletal adaptations opposite that expected for arboreal climbers. Results reject an arboreal capacity for the avian stem lineage, thus lending no support for the trees-down model. Support for a fully terrestrial ecology and origin of the avian flight stroke has broad implications for the origin of powered flight for this clade. A terrestrial origin for the avian flight stroke challenges the need for an intermediate gliding phase, presents the best resolved series of the evolution of vertebrate powered flight, and may differ fundamentally from the origin of bat and pterosaur flight, whose antecedents have been postulated to have been arboreal and gliding
Antiplatelet therapy with aspirin, clopidogrel, and dipyridamole versus clopidogrel alone or aspirin and dipyridamole in patients with acute cerebral ischaemia (TARDIS): a randomised, open-label, phase 3 superiority trial
Background: Intensive antiplatelet therapy with three agents might be more effective than guideline treatment for preventing recurrent events in patients with acute cerebral ischaemia. We aimed to compare the safety and efficacy of intensive antiplatelet therapy (combined aspirin, clopidogrel, and dipyridamole) with that of guideline-based antiplatelet therapy.
Methods: We did an international, prospective, randomised, open-label, blinded-endpoint trial in adult participants with ischaemic stroke or transient ischaemic attack (TIA) within 48 h of onset. Participants were assigned in a 1:1 ratio using computer randomisation to receive loading doses and then 30 days of intensive antiplatelet therapy (combined aspirin 75 mg, clopidogrel 75 mg, and dipyridamole 200 mg twice daily) or guideline-based therapy (comprising either clopidogrel alone or combined aspirin and dipyridamole). Randomisation was stratified by country and index event, and minimised with prognostic baseline factors, medication use, time to randomisation, stroke-related factors, and thrombolysis. The ordinal primary outcome was the combined incidence and severity of any recurrent stroke (ischaemic or haemorrhagic; assessed using the modified Rankin Scale) or TIA within 90 days, as assessed by central telephone follow-up with masking to treatment assignment, and analysed by intention to treat. This trial is registered with the ISRCTN registry, number ISRCTN47823388.
Findings: 3096 participants (1556 in the intensive antiplatelet therapy group, 1540 in the guideline antiplatelet therapy group) were recruited from 106 hospitals in four countries between April 7, 2009, and March 18, 2016. The trial was stopped early on the recommendation of the data monitoring committee. The incidence and severity of recurrent stroke or TIA did not differ between intensive and guideline therapy (93 [6%] participants vs 105 [7%]; adjusted common odds ratio [cOR] 0·90, 95% CI 0·67–1·20, p=0·47). By contrast, intensive antiplatelet therapy was associated with more, and more severe, bleeding (adjusted cOR 2·54, 95% CI 2·05–3·16, p<0·0001).
Interpretation: Among patients with recent cerebral ischaemia, intensive antiplatelet therapy did not reduce the incidence and severity of recurrent stroke or TIA, but did significantly increase the risk of major bleeding. Triple antiplatelet therapy should not be used in routine clinical practice
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