8,728 research outputs found
Non-linear Redshift-Space Power Spectra
Distances in cosmology are usually inferred from observed redshifts - an
estimate that is dependent on the local peculiar motion - giving a distorted
view of the three dimensional structure and affecting basic observables such as
the correlation function and power spectrum. We calculate the full non-linear
redshift-space power spectrum for Gaussian fields, giving results for both the
standard flat sky approximation and the directly-observable angular correlation
function and angular power spectrum. Coupling between large and small scale
modes boosts the power on small scales when the perturbations are small. On
larger scales power is slightly suppressed by the velocities perturbations on
smaller scales. The analysis is general, but we comment specifically on the
implications for future high-redshift observations, and show that the
non-linear spectrum has significantly more complicated angular structure than
in linear theory. We comment on the implications for using the angular
structure to separate cosmological and astrophysical components of 21 cm
observations.Comment: 22 pages, 6 figures, changed to version accepted in Physics Review
Milk Consumption Following Exercise Reduces Subsequent Energy Intake in Female Recreational Exercisers
The aim of this study was to evaluate the effects of skimmed milk as a recovery drink following moderate–vigorous cycling exercise on subsequent appetite and energy intake in healthy, female recreational exercisers. Utilising a randomised cross-over design, nine female recreational exercisers (19.7 ± 1.3 years) completed a V̇O2peak test followed by two main exercise trials. The main trials were conducted following a standardised breakfast. Following 30 min of moderate-vigorous exercise (65% V̇O2peak), either 600 mL of skimmed milk or 600 mL of orange drink (475 mL orange juice from concentrate, 125 mL water), which were isoenergetic (0.88 MJ), were ingested, followed 60 min later with an ad libitum pasta meal. Absolute energy intake was reduced 25.2% ± 16.6% after consuming milk compared to the orange drink (2.39 ± 0.70 vs. 3.20 ± 0.84 MJ, respectively; p = 0.001). Relative energy intake (in relation to the energy content of the recovery drinks and energy expenditure) was significantly lower after milk consumption compared to the orange drink (1.49 ± 0.72 vs. 2.33 ± 0.90 MJ, respectively; p = 0.005). There were no differences in AUC (× 1 h) subjective appetite parameters (hunger, fullness and desire to eat) between trials. The consumption of skimmed milk following 30 min of moderate-vigorous cycling exercise reduces subsequent energy intake in female recreational exercisers
The Relationship Of Accounting Majors Cognitive Style And Technological Proficiency: Are Students Prepared To Enter An Increasingly Knowledge-Based Profession?
The increasingly knowledge-based economy has generated technological innovations that demand different competencies for accounting practitioners. In particular, professional service firms such as public accounting practices depend on converting individual expertise into codified knowledge shared within firms and with customers. A key to this knowledge conversion cycle is proficiency with a number of technological tools. Further, individuals who can successfully participate in the creation and transfer of knowledge may have distinct cognitive style characteristics. One important question is whether cognitive style is related to technological proficiency.This study examines the cognitive styles of a group of undergraduate accounting majors (those intending careers in accounting) at several U. S. universities to examine any patterns in their cognitive style characteristics. This study further explores the relationship between cognitive style and technological proficiency. Results indicate that accounting students are predominantly linear-thinking (Concrete Sequential), consistent with prior literature. However, those who have stronger proficiency with computers and technology fit into different cognitive style groups. Implications for the accounting profession and accounting education are discussed
Massive neutrinos and magnetic fields in the early universe
Primordial magnetic fields and massive neutrinos can leave an interesting signal in the CMB temperature and polarization. We perform a systematic analysis of general perturbations in the radiation-dominated universe, accounting for any primordial magnetic field and including leading-order effects of the neutrino mass. We show that massive neutrinos qualitatively change the large-scale perturbations sourced by magnetic fields, but that the effect is much smaller than previously claimed. We calculate the CMB power spectra sourced by inhomogeneous primordial magnetic fields, from before and after neutrino decoupling, including scalar, vector and tensor modes, and consistently modeling the correlation between the density and anisotropic stress sources. In an appendix we present general series solutions for the possible regular primordial perturbations
Constraining Primordial Magnetism
Primordial magnetic fields could provide an explanation for the galactic
magnetic fields observed today, in which case they may also leave interesting
signals in the CMB and the small-scale matter power spectrum. We discuss how to
approximately calculate the important non-linear magnetic effects within the
guise of linear perturbation theory, and calculate the matter and CMB power
spectra including the SZ contribution. We then use various cosmological
datasets to constrain the form of the magnetic field power spectrum. Using
solely large-scale CMB data (WMAP7, QUaD and ACBAR) we find a 95% CL on the
variance of the magnetic field at 1 Mpc of B_\lambda < 6.4 nG. When we include
SPT data to constrain the SZ effect, we find a revised limit of B_\lambda < 4.1
nG. The addition of SDSS Lyman-alpha data lowers this limit even further,
roughly constraining the magnetic field to B_\lambda < 1.3 nG.Comment: 12 pages, 9 figure
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Decoding Key Nodes in the Metabolism of Cancer Cells: Sugar & Spice and All Things Nice
In the past 5 years, a convergence of studies has resulted in a broad appreciation in the cancer research community that reprogramming of cellular metabolism may be more central to cancer than appreciated in the past 30 years. The re-emergence of cancer metabolism stems in part from discoveries that a number of common oncogenes and tumor suppressor genes more directly control cell metabolism than previously thought. In addition, a number of what would previously have been called “card-carrying” metabolic enzymes have been identified as human tumor suppressors or oncogenes, causally mutated in a variety of human cancers. This growing appreciation of the role of altered cell metabolism has led to further investigation into the rate-limiting proteins involved in different aspects of the unique metabolism of tumor cells. Targeting cancer metabolism with drugs requires a therapeutic window in which tumor cells, compared to normal tissues, have a greater dependence on specific metabolic enzymes. Themes that have emerged in the past decade of developing oncogene-targeted cancer therapeutics suggest that tumors with distinct oncogenic lesions are likely to require drugs that target distinct metabolic pathways. Ultimately, the hope is that detailed knowledge of oncogene and tumor suppressor gene functions and their effects on metabolism will lead to drug combinations that will be far more effective in treating cancers
Indications for liver transplantation in the cyclosporine era
One hundred seventy orthotopic liver transplants were performed under conventional immunosuppression with azathioprine and steroids with 1- and 5-year survivals of 32.9% and 20.0%, respectively. Since the introduction of cyclosporine-prednisone therapy in March 1980, 313 primary orthotopic liver transplants have been performed. Actuarial survivals at 1 and 5 years have improved to 69.7% and 62.8%, respectively. Biliary atresia is now the most common indication for liver replacement. In adults, primary biliary cirrhosis and sclerosing cholangitis have become more common indications for transplantation, and alcoholic cirrhosis and primary liver malignancy as indications have declined. Early enthusiasm for liver transplantation in patients with hepatic cancer has been tempered by the finding that recurrence is both common and rapid. An increasing number of patients with inborn errors of metabolism originating in the liver are receiving transplants, including patients with Wilson's disease, tyrosinemia, alpha-1-antitrypsin deficiency, glycogen storage disease, familial hypercholesterolemia, and hemochromatosis. Survival in this group of patients has been excellent (74.4% at 1 and 5 years). A hemophiliac who received a transplant for postnecrotic cirrhosis has survived and may have been cured of his hemophilia. About 20% of patients require retransplantation for rejection, technical failure, or primary graft failure. Only 4 of the patients receiving retransplants under conventional immunosuppression survived beyond 6 months, and all died within 14 months of retransplantation. Sixty-eight patients have received retransplants under cyclosporine-prednisone. Thirty-one patients are surviving, all for at least 1 year. Six of the 12 patients requiring a third transplant are alive 2 to 3 years after the primary operation. An aggressive approach to retransplantation in the patient with a failed graft is justified
Intraoperative changes in blood coagulation and thrombelastographic monitoring in liver transplantation
The blood coagulation system of 66 consecutive patients undergoing consecutive liver transplantations was monitored by thrombelastograph and analytic coagulation profile. A poor preoperative coagulation state, decrease in levels of coagulation factors, progressive fibrinolysis, and whole blood clot lysis were observed during the preanhepatic and anhepatic stages of surgery. A further general decrease in coagulation factors and platelets, activation of fibrinolysis, and abrupt decrease in levels of factors V and VIII occurred before and with reperfusion of the homograft. Recovery of blood coagulability began 30-60 min after reperfusion of the graft liver, and coagulability had returned toward baseline values 2 hr after reperfusion. A positive correlation was shown between the variables of thrombelastography and those of the coagulation profile. Thrombelastography was shown to be a reliable and rapid monitoring system. Its use was associated with a 33% reduction of blood and fluid infusion volume, whereas blood coagulability was maintained without an increase in the number of blood product donors
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