709 research outputs found
Complex metal halides in fused alkali nitrates
The results of this investigation have provided additional information by chemical methods of the extent of association in fused salts. Association effects observed in solubility and rate studies in fused alkali nitrate are shown to be consistent with the assumption that complex ions such as those existing in aqueous solutions are formed between metal ions and halide ions. In addition, the rate studies suggest a mechanism for a reaction involving dichromate and nitrate ions in a fused alkali nitrate solvent
Spectral State Transitions of the Ultraluminous X-ray Source IC 342 X-1
We observed the Ultraluminous X-ray Source IC 342 X-1 simultaneously in X-ray
and radio with Chandra and the JVLA to investigate previously reported
unresolved radio emission coincident with the ULX. The Chandra data reveal a
spectrum that is much softer than observed previously and is well modelled by a
thermal accretion disc spectrum. No significant radio emission above the rms
noise level was observed within the region of the ULX, consistent with the
interpretation as a thermal state though other states cannot be entirely ruled
out with the current data. We estimate the mass of the black hole using the
modelled inner disc temperature to be based on a Shakura-Sunyaev
disc model. Through a study of the hardness and high-energy curvature of
available X-ray observations, we find that the accretion state of X-1 is not
determined by luminosity alone.Comment: 10 pages, 5 Figures. MNRAS: Accepted 2014 July 2
A Report of Nausea and Vomiting with Discontinuation of Chronic Use of Salvia divinorum
Introduction. This is the first reported case of gastrointestinal symptoms associated with withdrawal after chronic use of this substance. Case Presentation. A 51-year-old Caucasian woman was referred to a hospital with a 3-day history of nausea, vomiting, diarrhea, and abdominal discomfort. She reported no sick family members or contact with anyone who was ill. She did report smoking 3â5 cigarettes of the herb âSalviaâ consistently for 3-4 months and quit approximately 48 hours before symptoms appeared. Her use of the herb had been consistent; she smoked several cigarettes each day. Laboratory results were essentially normal including the white blood cell count. She received symptomatic treatment and was released after one day. Discussion. Salvinorin A, a kappa-opioid receptor agonist, is the major active ingredient of S. divinorum. The unique opioid properties of this herb may explain its ability to cause changes in intestinal transit time. Conclusion. A 51-year-old woman possibly developed gastrointestinal manifestations suggestive of withdrawal from Salvia divinorum after smoking the substance consistently for 3 to 4 months. The widespread use of this herb will make the potential for withdrawal syndromes more commonplace
An Evolutionary Perspective on Sedentary Behavior
Funding Information Royal Society wolfson merit award Natural Science Foundation of China. Grant Number: 91731303Peer reviewedPostprin
Performance, Stability, and Control Investigation at Mach Numbers from 0.4 to 0.9 of a Model of the "Swallow" with Outer Wing Panels Swept 25 degree with and without Power Simulation
An investigation of the performance, stability, and control characteristics of a variable-sweep arrow-wing model (the "Swallow") with the outer wing panels swept 25 deg has been conducted in the Langley 16-foot transonic tunnel. The wing was uncambered and untwisted and had RAE 102 airfoil sections with a thickness-to-chord ratio of 0.14 normal to the leading edge. Four outboard engines located above and below the wing provided propulsive thrust, and, by deflecting in the pitch direction and rotating in the lateral plane, also produced control forces. A pair of swept lateral fins and a single vertical fin were mounted on each engine nacelle to provide aerodynamic stability and control. Jets-off data were obtained with flow-through nacelles, stimulating the effects of inlet flow; jet thrust and hot-jet interference effects were obtained with faired-nose nacelles housing hydrogen peroxide gas generators. Six-component force and moment data were obtained through a Mach number range of 0.40 to 0.90 at angles of attack and angles of sideslip from 0 deg to 15 deg. Longitudinal, directional, and lateral control were obtained by deflecting the nacelle-fin combinations as elevators, rudders, and ailerons at several fixed angles for each control
Efficient Accommodation of May-Alias Information in SSA Form
We present an algorithm for incrementally including may-alias information into Static Single Assignment form by computing a sequence of increasingly precise (and correspondingly larger) partial SSA forms. Our experiments show significant speedup of our method over exhaustive use of may-alias information, as optimization problems converge well before most may-aliases are needed
Cortisol levels and expression of selected stress- and apoptosis-related genes in the embryos of Atlantic cod, Gadus morhua following short-term exposure to air
Inclusive Fitness and Differential Productivity Across the Life Course Determine Intergenerational Transfers in a Small-Scale Human Society
Transfers of resources between generations are an essential element in current models of human life-history evolution accounting for prolonged development, extended lifespan and menopause. Integrating these models with Hamiltonâs theory of inclusive fitness, we predict that the interaction of biological kinship with the age-schedule of resource production should be a key driver of intergenerational transfers. In the empirical case of Tsimaneâ foragerâhorticulturalists in Bolivian Amazonia, we provide a detailed characterization of net transfers of food according to age, sex, kinship and the net need of donors and recipients. We show that parents, grandparents and siblings provide significant net downward transfers of food across generations. We demonstrate that the extent of provisioning responds facultatively to variation in the productivity and demographic composition of families, as predicted by the theory. We hypothesize that the motivation to provide these critical transfers is a fundamental force that binds together human nuclear and extended families. The ubiquity of three-generational families in human societies may thus be a direct reflection of fundamental evolutionary constraints on an organismâs life-history and social organization
Content, cost and context: a framework for understanding human signaling systems
Humans frequently perform extravagant and seemingly costly behaviors, such as widely sharing hunted resources, erecting conspicuous monumental structures, and performing dramatic acts of religious devotion. Evolutionary anthropologists and archeologists have used signaling theory to explain the function of such displays, drawing inspiration from behavioral ecology, economics, and the social sciences. While signaling theory is broadly aimed at explaining honest communication, it has come to be strongly associated with the handicap principle, which proposes that such costly extravagance is in fact an adaptation for signal reliability. Most empirical studies of signaling theory have focused on obviously costly acts, and consequently anthropologists have likely overlooked a wide range of signals that also promote reliable communication. Here, we build on recent developments in signaling theory and animal communication, developing an updated framework that highlights the diversity of signal contents, costs, contexts, and reliability mechanisms present within human signaling systems. By broadening the perspective of signaling theory in human systems, we strive to identify promising areas for further empirical and theoretical work
A neutral hydrogen survey of polar ring galaxies IV. Parkes observations
A total of 33 polar ring galaxies and polar ring galaxy candidates were
observed in the 21-cm HI line with the 64-m Parkes radio telescope. The
objects, selected by their optical morphology, are all south of declination -39
degrees and in only 5 of them HI had been reported previously. HI line emission
was detected towards 18 objects, though in 3 cases the detection may be
confused by another galaxy in the telescope beam, and one is a marginal
detection. Eight objects were detected for the first time in HI, of which 5 did
not have previously known redshifts.Comment: Accepted by Astronomy and Astrophysics, 12/2/2002; new references
added on 20/2/200
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