553 research outputs found

    Human chorionic gonadotropin and GnRH effects on pregnancy survival in pregnant cows and resynchronized pregnancy rates

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    Dairy Research, 2007 is known as Dairy Day, 2007Experiments have shown human chorionic gonadotropin (hCG) to be more effective than gondadotropin releasing hormone (GnRH) as a means to ovulate follicles. Experiment 1 determined the effects of replacing the first injection of GnRH (day 7) with hCG or saline in a Resynch-Ovsynch protocol on pregnancy rates in cows subsequently diagnosed not pregnant and pregnancy survival in cows subsequently diagnosed pregnant (day 0). A second study determined the ovulation potential of hCG compared with GnRH and saline (Exp. 2). In Exp. 1, cows in 4 herds were assigned randomly based on lactation number, number of previous AI, and last test-day milk yield to treatments of 1,000 IU of hCG, 100 μg of GnRH, or left as untreated controls 7 days before pregnancy diagnosis. Cows found not pregnant were given PGF2α (day 0), then inseminated 72 hours later, concurrent with a GnRH injection (3 herds) or given GnRH 16 to 24 hours before AI at 72 hours (1 herd). Timed AI pregnancy rates tended (P = 0.08) to be reduced by saline (12.9%; n = 505) compared with GnRH (17.9%; n = 703) but not hCG (16.5%; n = 541). Among pregnant cows treated, pregnancy survival 4 to 9 weeks after initial pregnancy diagnosis differed among herds (P < 0.001); but in 1 herd, GnRH reduced pregnancy survival, whereas hCG seemed to increase survival compared with control. Only small differences were detected in the other 3 herds, except for a slight negative effect of hCG compared with control in 1 herd. Ovarian structures were monitored in herd 1 by using transrectal ultrasonography 0 and 7 days after treatment with hCG, GnRH, or saline (Exp. 2). A tendency for a treatment × pregnancy status interaction (P = 0.07) was detected. Incidences of ovulation in nonpregnant cows were: hCG (51.6%; n = 126), GnRH (46.1%; n = 102), and control (28.1%; n = 96), whereas those in pregnant cows were: hCG (59.3%; n = 59), GnRH (24.5%; n = 49), and saline (6.9%; n = 58). We concluded that: 1) initiating a Resynch-Ovsynch protocol 7 days before pregnancy diagnosis with saline reduced timed AI pregnancy rates (Exp. 1); 2) in pregnant cows treated with GnRH, pregnancy survival was slightly reduced in 1 of 4 herds (Exp. 1); and 3) incidence of new corpus luteum (CL) was greater after hCG than GnRH in pregnant cows but not in nonpregnant cows (Exp. 2)

    The Non-Trivial Effective Potential of the `Trivial' lambda Phi^4 Theory: A Lattice Test

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    The strong evidence for the `triviality' of (lambda Phi^4)_4 theory is not incompatible with spontaneous symmetry breaking. Indeed, for a `trivial' theory the effective potential should be given exactly by the classical potential plus the free-field zero-point energy of the shifted field; i.e., by the one-loop effective potential. When this is renormalized in a simple, but nonperturbative way, one finds, self-consistently, that the shifted field does become non-interacting in the continuum limit. For a classically scale-invariant (CSI) lambda Phi^4 theory one finds m_h^2 = 8 pi^2 v^2, predicting a 2.2 TeV Higgs boson. Here we extend our earlier work in three ways: (i) we discuss the analogy with the hard-sphere Bose gas; (ii) we extend the analysis from the CSI case to the general case; and (iii) we propose a test of the predicted shape of the effective potential that could be tested in a lattice simulation.Comment: 22 pages, LaTeX, DE-FG05-92ER40717-

    1000-MWe LMFBR ACCIDENT ANALYSIS AND SAFETY SYSTEM DESIGN STUDY. TOPICAL REPORT. ACCIDENT ANALYSIS METHODS.

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    Evaluation of human chorionic gonadotropin as a replacement for GnRH in an ovulation synchronization protocol before fixed-time insemination

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    Two experiments were conducted to evaluate the difference between gonadotropinreleasing hormone (GnRH) and human chorionic gonadotropin (hCG) given at the beginning of a timed AI protocol and their effects on fertility. In Experiment 1, beef cows (n = 672) at six different locations were assigned randomly to treatments based on age, body condition, and days postpartum. On day −10, cattle were treated with GnRH or hCG and a progesterone-releasing controlled internal drug release (CIDR) insert was placed in the vagina. An injection of PGF2α was given and CIDR inserts were removed on day −3. Cows were inseminated at one fixed timed at 62 hr (day 0) after CIDR insert removal. Pregnancy was diagnosed at 33 days (range of 32 to 35) after insemination to determine pregnancy rates. For cows that were pregnant after the first insemination, a second pregnancy diagnosis was conducted 35 days (range of 33 to 37) after the first diagnosis to determine pregnancy survival. Pregnancy rates were reduced by the hCG injection compared with the GnRH injection (39.1 vs. 53.5%). In Experiment 2, cattle were assigned randomly to three treatments, balanced evenly across the two treatments (GnRH vs. hCG) applied in Experiment 1. Cows were injected with GnRH, hCG, or saline seven days before the first pregnancy diagnosis of cows inseminated in Experiment 1. At the time of pregnancy diagnosis, cattle found not pregnant (n = 328) were given PGF2α and inseminated 56 hours later. A second pregnancy diagnosis was conducted 35 days (range of 33 to 37) after the second insemination to determine pregnancy rate at the second AI. Injections of GnRH, hCG, or saline had no effect on pregnancy rates of cows already pregnant to the first insemination. Pregnancy rates after second insemination in cows given an injection of hCG or GnRH, however, tended to be reduced. Percentage of cows pregnant after two timed inseminations exceeded 60% without any need to detect estrus

    Resonance fluorescence from a telecom-wavelength quantum dot

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    © 2016 Author(s).We report on resonance fluorescence from a single quantum dot emitting at telecom wavelengths. We perform high-resolution spectroscopy and observe the Mollow triplet in the Rabi regime - a hallmark of resonance fluorescence. The measured resonance-fluorescence spectra allow us to rule out pure dephasing as a significant decoherence mechanism in these quantum dots. Combined with numerical simulations, the experimental results provide robust characterisation of charge noise in the environment of the quantum dot. Resonant control of the quantum dot opens up new possibilities for the on-demand generation of indistinguishable single photons at telecom wavelengths as well as quantum optics experiments and direct manipulation of solid-state qubits in telecom-wavelength quantum dots

    Polariton condensation and lasing in optical microcavities - the decoherence driven crossover

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    We explore the behaviour of a system which consists of a photon mode dipole coupled to a medium of two-level oscillators in a microcavity in the presence of decoherence. We consider two types of decoherence processes which are analogous to magnetic and non-magnetic impurities in superconductors. We study different phases of this system as the decoherence strength and the excitation density is changed. For a low decoherence we obtain a polariton condensate with comparable excitonic and photonic parts at low densities and a BCS-like state with bigger photon component due to the fermionic phase space filling effect at high densities. In both cases there is a large gap in the density of states. As the decoherence is increased the gap is broadened and suppressed, resulting in a gapless condensate and finally a suppression of the coherence in a low density regime and a laser at high density limit. A crossover between these regimes is studied in a self-consistent way analogous to the Abrikosov and Gor'kov theory of gapless superconductivity.Comment: 17 pages, 8 figures, submitted to PR

    International Consortium for Health Outcomes Measurement (ICHOM): Standardized Patient-Centered Outcomes Measurement Set for Heart Failure Patients

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    Whereas multiple national, international, and trial registries for heart failure have been created, international standards for clinical assessment and outcome measurement do not currently exist. The working group's objective was to facilitate international comparison in heart failure care, using standardized parameters and meaningful patient-centered outcomes for research and quality of care assessments. The International Consortium for Health Outcomes Measurement recruited an international working group of clinical heart failure experts, researchers, and patient representatives to define a standard set of outcomes and risk-adjustment variables. This was designed to document, compare, and ultimately improve patient care outcomes in the heart failure population, with a focus on global feasibility and relevance. The working group employed a Delphi process, patient focus groups, online patient surveys, and multiple systematic publications searches. The process occurred over 10 months, employing 7 international teleconferences. A 17-item set has been established, addressing selected functional, psychosocial, burden of care, and survival outcome domains. These measures were designed to include all patients with heart failure, whether entered at first presentation or subsequent decompensation, excluding cardiogenic shock. Sources include clinician report, administrative data, and validated patient-reported outcome measurement tools: the Kansas City Cardiomyopathy Questionnaire; the Patient Health Questionnaire-2; and the Patient-Reported Outcomes Measurement Information System. Recommended data included those to support risk adjustment and benchmarking across providers and regions. The International Consortium for Health Outcomes Measurement developed a dataset designed to capture, compare, and improve care for heart failure, with feasibility and relevance for patients and clinicians worldwide

    Predicting haemodynamic networks using electrophysiology: The role of non-linear and cross-frequency interactions

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    Understanding the electrophysiological basis of resting state networks (RSNs) in the human brain is a critical step towards elucidating how inter-areal connectivity supports healthy brain function. In recent years, the relationship between RSNs (typically measured using haemodynamic signals) and electrophysiology has been explored using functional Magnetic Resonance Imaging (fMRI) and magnetoencephalography (MEG). Significant progress has been made, with similar spatial structure observable in both modalities. However, there is a pressing need to understand this relationship beyond simple visual similarity of RSN patterns. Here, we introduce a mathematical model to predict fMRI-based RSNs using MEG. Our unique model, based upon a multivariate Taylor series, incorporates both phase and amplitude based MEG connectivity metrics, as well as linear and non-linear interactions within and between neural oscillations measured in multiple frequency bands. We show that including non-linear interactions, multiple frequency bands and cross-frequency terms significantly improves fMRI network prediction. This shows that fMRI connectivity is not only the result of direct electrophysiological connections, but is also driven by the overlap of connectivity profiles between separate regions. Our results indicate that a complete understanding of the electrophysiological basis of RSNs goes beyond simple frequency-specific analysis, and further exploration of non-linear and cross-frequency interactions will shed new light on distributed network connectivity, and its perturbation in pathology
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