638 research outputs found

    Validation of a New Ramping Aerobic Exercise Protocol (NDKS) in Overweight, Obese, and Normal Weight Individuals

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    International Journal of Exercise Science 15(4): 386-398, 2022. The research purpose was to establish reliability and validity of determining VO2max via a new NDKS (Nustad Dressler Kobes Saghiv; named for the sir names of department faculty at the time) ramping protocol compared to the Standard Bruce protocol in normal weight, overweight, and obese individuals. Forty-two physically active participants (23M, 19F) ages 18-28 years were grouped into normal weight (N = 15, 8F, BMI 18.5-24.9 kg/m2), overweight (N = 27, 11F, BMI = 25-29.9 kg/m2), and Class I obese (N = 7, 1F, BMI = 30-34.9 kg/m2). Blood pressure, heart rate, blood lactate, respiratory exchange ratio, test duration, rate of perceived exertion, and preference via survey were analyzed during each test. Test-retest reliability of the NDKS was determined first, via tests scheduled one week apart. The NDKS was then validated by comparison with results of the Standard Bruce protocol; tests also conducted one week apart. The normal weight group’s Cronbach’s Alpha was .995 for absolute VO2max (L/min) and .968 for relative VO2max (mL/kg.min). Overweight/obese Cronbach’s Alpha for absolute VO2max (L/min) was .960 and for relative VO2max (mL/kg.min) .908. Relative VO2max was slightly higher with NDKS and test time lower compared to the Bruce (p \u3c .05). 92.3% of subjects identified more localized muscle fatigue with the Bruce protocol vs NDKS. The NDKS is a reliable and valid exercise test which can be used to determine VO2max in physically active, young normal weight, overweight and obese individuals

    Use of Ecological Sites in Managing Wildlife and Livestock: An Example with Prairie Dogs

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    On the Ground The perception of prairie dogs among Native Americans living on the Standing Rock Sioux Reservation is mixed. Some Native Americans focus on the loss of forage productivity, whereas others are interested in the cultural and ecological aspects of prairie dogs. The use of ecological sites may provide a mechanism for developing a management framework that would consider both livestock and prairie dogs. The three ecological sites we surveyed had large differences in off-colony standing crop, but in 2 of the 3 years we surveyed, there were no differences between standing crop on-colony. This suggests that management of prairie dogs on rangelands should focus on limiting prairie dogs on more productive ecological sites with less productive sites receiving less emphasis

    Qualitative Environmental Health Research: An Analysis of the Literature, 1991-2008

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    BACKGROUND. Recent articles have advocated for the use of qualitative methods in environmental health research. Qualitative research uses nonnumeric data to understand people's opinions, motives, understanding, and beliefs about events or phenomena. OBJECTIVE. In this analysis of the literature, I report the use of qualitative methods and data in the study of the relationship between environmental exposures and human health. DATA SOURCES. A primary search on ISI Web of Knowledge/Web of Science for peer-reviewed journal articles dated from 1991 through 2008 included the following three terms: qualitative, environ*, and health. Inclusion and exclusion criteria are described. DATA EXTRACTION. Searches resulted in 3,155 records. Data were extracted and findings of articles analyzed to determine where and by whom qualitative environmental health research is conducted and published, the types of methods and analyses used in qualitative studies of environmental health, and the types of information qualitative data contribute to environmental health. DATA SYNTHESIS. Ninety-one articles met inclusion criteria. These articles were published in 58 different journals, with a maximum of eight for a single journal. The results highlight a diversity of disciplines and techniques among researchers who used qualitative methods to study environmental health, with most studies relying on one-on-one interviews. Details of the analyses were absent from a large number of studies. Nearly all of the studies identified increased scientific understanding of lay perceptions of environmental health exposures. DISCUSSION AND CONCLUSIONS. Qualitative data are published in traditionally quantitative environmental health studies to a limited extent. However, this analysis demonstrates the potential of qualitative data to improve understanding of complex exposure pathways, including the influence of social factors on environmental health, and health outcomes.National Institute of Environmental Health Sciences (R25 ES012084, P42ES007381

    Reichenbach's Common Cause Principle in Algebraic Quantum Field Theory with Locally Finite Degrees of Freedom

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    In the paper it will be shown that Reichenbach's Weak Common Cause Principle is not valid in algebraic quantum field theory with locally finite degrees of freedom in general. Namely, for any pair of projections A and B supported in spacelike separated double cones O(a) and O(b), respectively, a correlating state can be given for which there is no nontrivial common cause (system) located in the union of the backward light cones of O(a) and O(b) and commuting with the both A and B. Since noncommuting common cause solutions are presented in these states the abandonment of commutativity can modulate this result: noncommutative Common Cause Principles might survive in these models

    Witnessing causal nonseparability

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    Our common understanding of the physical world deeply relies on the notion that events are ordered with respect to some time parameter, with past events serving as causes for future ones. Nonetheless, it was recently found that it is possible to formulate quantum mechanics without any reference to a global time or causal structure. The resulting framework includes new kinds of quantum resources that allow performing tasks - in particular, the violation of causal inequalities - which are impossible for events ordered according to a global causal order. However, no physical implementation of such resources is known. Here we show that a recently demonstrated resource for quantum computation - the quantum switch - is a genuine example of "indefinite causal order". We do this by introducing a new tool - the causal witness - which can detect the causal nonseparability of any quantum resource that is incompatible with a definite causal order. We show however that the quantum switch does not violate any causal nequality.Comment: 15 + 12 pages, 5 figures. Published versio

    Generic Bell correlation between arbitrary local algebras in quantum field theory

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    We prove that for any two commuting von Neumann algebras of infinite type, the open set of Bell correlated states for the two algebras is norm dense. We then apply this result to algebraic quantum field theory -- where all local algebras are of infinite type -- in order to show that for any two spacelike separated regions, there is an open dense set of field states that dictate Bell correlations between the regions. We also show that any vector state cyclic for one of a pair of commuting nonabelian von Neumann algebras is entangled (i.e., nonseparable) across the algebras -- from which it follows that every field state with bounded energy is entangled across any two spacelike separated regions.Comment: Third version; correction in the proof of Proposition

    In defense of the epistemic view of quantum states: a toy theory

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    We present a toy theory that is based on a simple principle: the number of questions about the physical state of a system that are answered must always be equal to the number that are unanswered in a state of maximal knowledge. A wide variety of quantum phenomena are found to have analogues within this toy theory. Such phenomena include: the noncommutativity of measurements, interference, the multiplicity of convex decompositions of a mixed state, the impossibility of discriminating nonorthogonal states, the impossibility of a universal state inverter, the distinction between bi-partite and tri-partite entanglement, the monogamy of pure entanglement, no cloning, no broadcasting, remote steering, teleportation, dense coding, mutually unbiased bases, and many others. The diversity and quality of these analogies is taken as evidence for the view that quantum states are states of incomplete knowledge rather than states of reality. A consideration of the phenomena that the toy theory fails to reproduce, notably, violations of Bell inequalities and the existence of a Kochen-Specker theorem, provides clues for how to proceed with this research program.Comment: 32 pages, REVTEX, based on a talk given at the Rob Clifton Memorial Conference, College Park, May 2003; v2: minor modifications throughout, updated reference

    Non-local Correlations are Generic in Infinite-Dimensional Bipartite Systems

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    It was recently shown that the nonseparable density operators for a bipartite system are trace norm dense if either factor space has infinite dimension. We show here that non-local states -- i.e., states whose correlations cannot be reproduced by any local hidden variable model -- are also dense. Our constructions distinguish between the cases where both factor spaces are infinite-dimensional, where we show that states violating the CHSH inequality are dense, and the case where only one factor space is infinite-dimensional, where we identify open neighborhoods of nonseparable states that do not violate the CHSH inequality but show that states with a subtler form of non-locality (often called "hidden" non-locality) remain dense.Comment: 8 pages, RevTe
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