Deconfinement of neutron star matter within the Nambu-Jona-Lasinio model

We study the deconfinement transition of hadronic matter into quark matter under neutron star conditions assuming color and flavor conservation during the transition. We use a two-phase description. For the hadronic phase we use different parameterizations of a non-linear Walecka model which includes the whole baryon octet. For the quark matter phase we use an SU(3)_f Nambu-Jona-Lasinio effective model including color superconductivity. Deconfinement is considered to be a first order phase transition that conserves color and flavor. It gives a short-lived transitory colorless-quark-phase that is not in beta-equilibrium, and decays to a stable configuration in tau ~ tau_{weak} ~ 10^{-8} s. However, in spite of being very short lived, the transition to this intermediate phase determines the onset of the transition inside neutron stars. We find the transition free-energy density for temperatures typical of neutron star interiors. We also find the critical mass above which compact stars should contain a quark core and below which they are safe with respect to a sudden transition to quark matter. Rather independently on the stiffness of the hadronic equation of state (EOS) we find that the critical mass of hadronic stars (without trapped neutrinos) is in the range of ~ 1.5 - 1.8 solar masses. This is in coincidence with previous results obtained within the MIT Bag model.Comment: 10 pages, 2 figure

Triglyceride-rich lipoproteins prevent septic death in rats.

Triglyceride-rich lipoproteins bind and inactive bacterial endotoxin in vitro and prevent death when given before a lethal dose of endotoxin in animals. However, lipoproteins have not yet been demonstrated to improve survival in polymicrobial gram-negative sepsis. We therefore tested the ability of triglyceride-rich lipoproteins to prevent death after cecal ligation and puncture (CLP) in rats. Animals were given bolus infusions of either chylomicrons (1 g triglyceride/kg per 4 h) or an equal volume of saline for 28 h after CLP. Chylomicron infusions significantly improved survival (measured at 96 h) compared with saline controls (80 vs 27%, P < or = 0.03). Chylomicron infusions also reduced serum levels of endotoxin, measured 90 min (26 +/- 3 vs 136 +/- 51 pg/ml, mean +/- SEM, P < or = 0.03) and 6 h (121 +/- 54 vs 1,026 +/- 459 pg/ml, P < or = 0.05) after CLP. The reduction in serum endotoxin correlated with a reduction in serum tumor necrosis factor, measured 6 h after CLP (0 +/- 0 vs 58 +/- 24 pg/ml, P < or = 0.03), suggesting that chylomicrons improve survival in this model by limiting macrophage exposure to endotoxin and thereby reducing secretion of inflammatory cytokines. Infusions of a synthetic triglyceride-rich lipid emulsion (Intralipid; KabiVitrum, Inc., Alameda, CA) (1 g triglyceride/kg) also significantly improved survival compared with saline controls (71 vs 27%, P < or = 0.03). These data demonstrate that triglyceride-rich lipoproteins can protect animals from lethal polymicrobial gram-negative sepsis

Two flavor color superconductivity in nonlocal chiral quark models

We study the competence between chiral symmetry restoration and two flavor color superconductivity (2SC) using a relativistic quark model with covariant nonlocal interactions. We consider two different nonlocal regulators: a Gaussian regulator and a Lorentzian regulator. We find that although the phase diagrams are qualitative similar to those obtained using models with local interactions, in our case the superconducting gaps at medium values of the chemical potential are larger. Consequently, we obtain that in that region the critical temperatures for the disappearance of the 2SC phase might be of the order of 100-120 MeV. We also find that for ratios of the quark-quark and quark-antiquark couplings somewhat above the standard value 3/4, the end point and triple point in the $T-\mu$ phase diagram meet and a phase where both the chiral and diquark condensates are non-negligible appears.Comment: 15 pages incl. 5 Postscript figure

Effect of supplementary amino acids and adenosine phosphates on motility and metabolism of bovine spermatozoa

This bulletin reports on Department of Dairy Husbandry Research Project 54, Artificial insemination--P. [2].Digitized 2007 AES.Includes bibliographical references (pages 18-20)

Association of low level viremia with inflammation and mortality in HIV-infected adults.

BackgroundWhether HIV viremia, particularly at low levels is associated with inflammation, increased coagulation, and all-cause mortality is unclear.MethodsThe associations of HIV RNA level with C-reactive protein (CRP), fibrinogen, interleukin (IL)-6 and mortality were evaluated in 1116 HIV-infected participants from the Study of Fat Redistribution and Metabolic Change in HIV infection. HIV RNA level was categorized as undetectable (i.e., "target not detected"), 1-19, 20-399, 400-9999, and ≥ 10,000 copies/ml. Covariates included demographics, lifestyle, adipose tissue, and HIV-related factors.ResultsHIV RNA level had little association with CRP. Categories of HIV RNA below 10,000 copies/ml had similar levels of IL-6 compared with an undetectable HIV RNA level, while HIV RNA ≥ 10,000 copies/ml was associated with 89% higher IL-6 (p<0.001). This association was attenuated by ~50% after adjustment for CD4+ cell count. Higher HIV RNA was associated with higher fibrinogen. Compared to an undetectable HIV RNA level, fibrinogen was 0.6%, 1.9%, 4.5%, 4.6%, and 9.4% higher across HIV RNA categories, respectively, and statistically significant at the highest level (p = 0.0002 for HIV RNA ≥ 10,000 copies/ml). Higher HIV RNA was associated with mortality during follow-up in unadjusted analysis, but showed little association after adjustment for CD4+ cell count and inflammation.ConclusionHIV RNA ≥ 10,000 copies/ml was associated with higher IL-6 and fibrinogen, but lower levels of viremia appeared similar, and there was little association with CRP. The relationship of HIV RNA with IL-6 was strongly affected by CD4 cell depletion. After adjustment for CD4+ cell count and inflammation, viremia did not appear to be substantially associated with mortality risk over 5 years

Understanding variation in men’s help-seeking for cancer symptoms: a semi-structured interview study

Men appear more likely to delay seeking medical advice for cancer symptoms, resulting in later stage at diagnosis and poorer health outcomes. Limited research has investigated variation in men’s experiences of and responses to cancer symptoms. This study examined the psychosocial aspects of men’s help-seeking for cancer symptoms, as well as potential variation across men residing in urban and rural Australia. Semi-structured interviews were conducted with men recently diagnosed with cancer (n=13). Participants’ partners (n=8) were recruited to enable data triangulation. Interview schedules addressed participants’ pathway to cancer treatment, cancer knowledge, masculinity, and rural living. A theoretical thematic analysis approach was used. Medical help-seeking behaviour was similar for participants residing in urban and rural areas. Five key themes and one sub-theme were identified, including: symptom factors, traditional masculine norms (sub-theme: women’s health-related responsibilities), level of concern, conflicting responsibilities and access, and trust in medical professionals. Participants from rural Australia experienced greater access difficulties and noted optimism regarding symptoms. Results highlight important within-gender differences in the psychosocial barriers to help-seeking for cancer symptoms. Future research should further explore variation between men and test the predictive strength of factors