12,297 research outputs found
Nubian a-group and Egyptian Naqada trade relations in the predynastic
Full text linkThe archaeological study of interregional trade provides the unique opportunity to reconstruct not only the foreign relations of cultures that are no longer in existence, but also how these relations evolved over extended periods of time. This study examines interactions between the Egyptian Naqada and Nubian A-Group cultures - located near the present day border of Egypt and The Sudan - between 3800 and 2900 B.C.E. Cemeteries from each group were compared looking at frequency of grave goods, burial architecture, the treatment of the deceased, and how these factors changed over time, in order to determine: (a) the degree of social complexity in Nubian A-Group society, and (b) the ability of trade to influence culture. The study found that while Nubian A-Group society shows some signs of social complexity, the A-Group culture was not nearly as complex as the near state-level society seen with the Egyptian Naqada culture. In line with this, the study found that there was a disproportionate level of cultural influence between the two groups, with the Nubian A-Group culture adopting many Egyptian traits
Evolution of cooperation among tumor cells
No full textThe evolution of cooperation has a well established theoretical framework based on game theory. This approach has made valuable contributions to a wide variety of disciplines, including political science, economics, and evolutionary biology. Existing cancer theory suggests that individual clones of cancer cells evolve independently from one another, acquiring all of the genetic traits or hallmarks necessary to form a malignant tumor. It is also now recognized that tumors are heterotypic, with cancer cells interacting with normal stromal cells within the issue microenvironment, including endothelial, stromal, and nerve cells. This tumor cell???stromal cell interaction in itself is a form of commensalism, because it has been demonstrated that these nonmalignant cells support and even enable tumor growth. Here, we add to this theory by regarding tumor cells as game players whose interactions help to determine their Darwinian fitness. We marshal evidence that tumor cells overcome certain host defenses by means of diffusible products. Our original contribution is to raise the possibility that two nearby cells can protect each other from a set of host defenses that neither could survive alone. Cooperation can evolve as byproduct mutualism among genetically diverse tumor cells. Our hypothesis supplements, but does not supplant, the traditional view of carcinogenesis in which one clonal population of cells develops all of the necessary genetic traits independently to form a tumor. Cooperation through the sharing of diffusible products raises new questions about tumorigenesis and has implications for understanding observed phenomena, designing new experiments, and developing new therapeutic approaches.Author manuscript. Published in final edited form as: Proc Natl Acad Sci U S A. 2006 September 5; 103(36): 13474-13479.The final published version of this article is located at: www.pnas.org/cgi/doi/10.1073/pnas.0606053103NIH U56 CA113004; to David E. AxelrodR.A. was supported by National Science Foundation (NSF) Grant SES-0240852. D.E.A. was supported by NSF Grant IIS-0312953, National Institutes of Health (NIH) Grant U56 CA113004, and New Jersey Commission on Cancer Research Grant 1076-CCR-SO. K.J.P. is an American Cancer Society Clinical Research Professor and is supported by NIH Grants CA69568, CA102872, and CA093900.NIH CA69568; to Kenneth J. PientaNIH CA102872; to Kenneth J. PientaNIH CA093900; to Kenneth J. PientaNSF SES-0240852; to Robert AxelrodNJ Commission on Cancer Research 1076-CCR-SO; to David E. AxelrodAlso available in PubMed Central. PMCID: PMC155738
Differential sensitivity to the acute psychotomimetic effects of delta-9-tetrahydrocannabinol associated with its differential acute effects on glial function and cortisol
No full textBackground: Cannabis use has been associated with psychosis through exposure to delta-9-tetrahydrocannabinol (Δ9-THC), its key psychoactive ingredient. Although preclinical and human evidence suggests that Δ9-THC acutely modulates glial function and hypothalamic-pituitary-adrenal (HPA) axis activity, whether differential sensitivity to the acute psychotomimetic effects of Δ9-THC is associated with differential effects of Δ9-THC on glial function and HPA-axis response has never been tested. Methods: A double-blind, randomized, placebo-controlled, crossover study investigated whether sensitivity to the psychotomimetic effects of Δ9-THC moderates the acute effects of a single Δ9-THC dose (1.19 mg/2 ml) on myo-inositol levels, a surrogate marker of glia, in the Anterior Cingulate Cortex (ACC), and circadian cortisol levels, the key neuroendocrine marker of the HPA-axis, in a set of 16 healthy participants (seven males) with modest previous cannabis exposure. Results: The Δ9-THC-induced change in ACC myo-inositol levels differed significantly between those sensitive to (Δ9-THC minus placebo; M = -0.251, s.d. = 1.242) and those not sensitive (M = 1.615, s.d. = 1.753) to the psychotomimetic effects of the drug (t(14) = 2.459, p = 0.028). Further, the Δ9-THC-induced change in cortisol levels over the study period (baseline minus 2.5 h post-drug injection) differed significantly between those sensitive to (Δ9-THC minus placebo; M = -275.4, s.d. = 207.519) and those not sensitive (M = 74.2, s.d. = 209.281) to the psychotomimetic effects of the drug (t(13) = 3.068, p = 0.009). Specifically, Δ9-THC exposure lowered ACC myo-inositol levels and disrupted the physiological diurnal cortisol decrease only in those subjects developing transient psychosis-like symptoms. Conclusions: The interindividual differences in transient psychosis-like effects of Δ9-THC are the result of its differential impact on glial function and stress response
Association between cannabinoid 1 receptor availability and glutamate levels in healthy controls and drug-free patients with first episode psychosis
Full text linkCannabinoid 1 receptor and glutamatergic dysfunction have both been implicated in the pathophysiology of schizophrenia. However, it remains unclear if cannabinoid 1 receptor alterations shown in drug-naïve/free patients with first episode psychosis may be linked to glutamatergic alterations in the illness. We aimed to investigate glutamate levels and cannabinoid 1 receptor levels in the same region in patients with first episode psychosis. Forty volunteers (20 healthy volunteers, 20 drug-naïve/free patients with first episode psychosis diagnosed with schizophrenia/schizoaffective disorder) were included in the study. Glutamate levels were measured using proton magnetic resonance spectroscopy. CB1R availability was indexed using the distribution volume (VT (ml/cm3)) of [11C]MePPEP using arterial blood sampling. There were no significant associations between ACC CB1R levels and ACC glutamate levels in controls (R = − 0.24, p = 0.32) or patients (R = − 0.10, p = 0.25). However, ACC glutamate levels were negatively associated with CB1R availability in the striatum (R = − 0.50, p = 0.02) and hippocampus (R = − 0.50, p = 0.042) in controls, but these associations were not observed in patients (p > 0.05). Our findings extend our previous work in an overlapping sample to show, for the first time as far as we’re aware, that cannabinoid 1 receptor alterations in the anterior cingulate cortex are shown in the absence of glutamatergic dysfunction in the same region, and indicate potential interactions between glutamatergic signalling in the anterior cingulate cortex and the endocannabinoid system in the striatum and hippocampus
sj-docx-1-jop-10.1177_02698811231168243 – Supplemental material for Signatures of exposure to childhood trauma in young adults in the structure and neurochemistry of the superior temporal gyrus
No full textSupplemental material, sj-docx-1-jop-10.1177_02698811231168243 for Signatures of exposure to childhood trauma in young adults in the structure and neurochemistry of the superior temporal gyrus by Piril Hepsomali, Sandra Machon, Holly Barker, David J Lythgoe, Kenneth Hugdahl, Maria Gudbrandsen and Paul Allen in Journal of Psychopharmacology</p
The Arts Interview. Dr. David Pitt : The Truant Years, E. J. Pratt
No full textHost Fred Hollingshurst interviews Dr. David Pitt of Memorial University, who discusses the life and work of Newfoundland poet E. J. Pratt. Pitt is the author of E. J. Pratt: The Truant Years, 1881-1927
Fly about round me coursing, swallow sweet birds come near [first line]
No full textstrophicpiano and voiceCover is duplicated in 125.115b.Johns Hopkins University, Levy Sheet Music Collection, Box
125, Item 115aTranslated From the French of Volney L'Hotelier by Samuel J. Gardner, Esq. The Music by Felicien David (Author of "Le Desert").E.G. Warren, Engr
Fly about round me coursing, swallow sweet birds come near [first line]
No full textstrophicpiano and voiceCover is duplicated in 125.115b.Johns Hopkins University, Levy Sheet Music Collection, Box
125, Item 115aTranslated From the French of Volney L'Hotelier by Samuel J. Gardner, Esq. The Music by Felicien David (Author of "Le Desert").E.G. Warren, Engr
Interview with David Dunn on the subject of bark beetle sounds
No full textAnimaliaArthropodaInsectaColeopteraCompressed from .wav format into .mp3 delivery formatComposer and recording engineer David Dunn describes his recordings of bark beetles in New Mexico, and some of the possible causes and consequences of bark beetle infestations devastating pine forests throughout the WestSounds were recorded using a modified transducer inserted into the bark of the tree, and are taken with permission of the author from the compact disc "The Sound of Light in Trees" produced by David Dunn in collaboration with the Acoustic Ecology Institute. Scientists say that bark beetle populations are increasing in large part because of increased drought and milder winters due to global warming
Unsung Hero of Gettysburg: The Story of Union General David McMurtrie Gregg
Full text linkReviewer David J. Eicher writes that Longacre presents a “fine narrative,” in which the author weaves stories of the general’s personal life together with battle scenes that “are interesting and move along at a fast pace.” Longacre “clearly admires his subject,” Eicher writes, but the work “is not without offering criticism.” With Unsung Hero of Gettysburg, the general “has finally received a biography that delivers the details of a soldier’s full and interesting life,” over a century after Gregg’s death
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