657 research outputs found
Vacuum structure of pure gauge theories on the lattice
We present results from simulations on two aspects of quark confinement in
the pure gauge sector. First is the calculation of the profile of the flux tube
connecting a static pair in . By using the Michael sum rules
as a constraint we give evidence that the energy density at the center of the
flux tube goes to a constant as a function of quark separation. Slow variation
of the width and energy density is not ruled out. Secondly in the confined
phase of lattice we calculate the curl of the magnetic monopole current
and show that the dual London equation is satisfied and that the electric
fluxoid is quantized.Comment: 14 pages (no figures, please request preprint), LSU HE NO. 130-199
PON1 status does not influence cholinesterase activity in Egyptian agricultural workers exposed to chlorpyrifos.
Animal studies have shown that paraoxonase 1 (PON1) genotype can influence susceptibility to the organophosphorus pesticide chlorpyrifos (CPF). However, Monte Carlo analysis suggests that PON1 genotype may not affect CPF-related toxicity at low exposure conditions in humans. The current study sought to determine the influence of PON1 genotype on the activity of blood cholinesterase as well as the effect of CPF exposure on serum PON1 in workers occupationally exposed to CPF. Saliva, blood and urine were collected from agricultural workers (n=120) from Egypt's Menoufia Governorate to determine PON1 genotype, blood cholinesterase activity, serum PON1 activity towards chlorpyrifos-oxon (CPOase) and paraoxon (POase), and urinary levels of the CPF metabolite 3,5,6-trichloro-2-pyridinol (TCPy). The PON1 55 (Pâ€0.05) but not the PON1 192 genotype had a significant effect on CPOase activity. However, both the PON1 55 (Pâ€0.05) and PON1 192 (Pâ€0.001) genotypes had a significant effect on POase activity. Workers had significantly inhibited AChE and BuChE after CPF application; however, neither CPOase activity nor POase activity was associated with ChE depression when adjusted for CPF exposure (as determined by urinary TCPy levels) and stratified by PON1 genotype. CPOase and POase activity were also generally unaffected by CPF exposure although there were alterations in activity within specific genotype groups. Together, these results suggest that workers retained the capacity to detoxify chlorpyrifos-oxon under the exposure conditions experienced by this study population regardless of PON1 genotype and activity and that effects of CPF exposure on PON1 activity are minimal
Elastic turbulence homogenizes fluid transport in stratified porous media
Many key environmental, industrial, and energy processes rely on controlling
fluid transport within subsurface porous media. These media are typically
structurally heterogeneous, often with vertically-layered strata of distinct
permeabilities -- leading to uneven partitioning of flow across strata, which
can be undesirable. Here, using direct in situ visualization, we demonstrate
that polymer additives can homogenize this flow by inducing a purely-elastic
flow instability that generates random spatiotemporal fluctuations and excess
flow resistance in individual strata. In particular, we find that this
instability arises at smaller imposed flow rates in higher-permeability strata,
diverting flow towards lower-permeability strata and helping to homogenize the
flow. Guided by the experiments, we develop a parallel-resistor model that
quantitatively predicts the flow rate at which this homogenization is optimized
for a given stratified medium. Thus, our work provides a new approach to
homogenizing fluid and passive scalar transport in heterogeneous porous media
HI intensity mapping with FAST
We discuss the detectability of large-scale HI intensity fluctuations using
the FAST telescope. We present forecasts for the accuracy of measuring the
Baryonic Acoustic Oscillations and constraining the properties of dark energy.
The FAST -beam L-band receivers (-- GHz) can provide
constraints on the matter power spectrum and dark energy equation of state
parameters () that are comparable to the BINGO and CHIME
experiments. For one year of integration time we find that the optimal survey
area is . However, observing with larger frequency coverage
at higher redshift (-- GHz) improves the projected errorbars on the
HI power spectrum by more than confidence level. The combined
constraints from FAST, CHIME, BINGO and Planck CMB observations can provide
reliable, stringent constraints on the dark energy equation of state.Comment: 7 pages, 3 figures, submitted to "Frontiers in Radio Astronomy and
FAST Early Sciences Symposium 2015" conference proceedin
Crosstalk between hemostasis inhibitors and cholesterol biomarkers in multiple sclerosis
The individual roles of cholesterol pathway biomarkers (CPB) and hemostasis inhibitors with neuroimaging outcomes were previously investigated in multiple sclerosis (MS). The purpose of this extension study was to investigate potential crosstalk between plasma CPB [total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C) and apolipoproteins (Apo) ApoA-I, ApoAII, ApoB, ApoC-II and ApoE] and hemostasis inhibitors [heparin cofactor-II (HCII), protein C (PC), protein S (PS), thrombomodulin, ADAMTS13 and PAI-1] in a cohort of 127 MS patients, and 40 healthy individuals (HI). The associations were assessed with regressions. In MS patients, HCII was positively associated with TC, LDL-C, HDL-C and ApoA-I (p=0.028, 0.027, 0.002 and 0.027, respectively) but negatively associated with ApoCII (p=0.018). PC was positively associated with ApoC-II (p=0.001) and ApoB (p=0.016) whereas PS was associated with TC (p=0.024) and ApoE (p=0.003) in MS. The ApoC-II associations were not observed in HI. The negative association between ApoC-II and HCll was an exception amongst other positive associations between CPB and hemostasis inhibitors in MS. CPB do not modulate the PC associations with neurodegeneration in MS
Crosstalk between hemostasis inhibitors and cholesterol biomarkers in multiple sclerosis
The individual roles of cholesterol pathway biomarkers (CPB) and hemostasis inhibitors with neuroimaging outcomes were previously investigated in multiple sclerosis (MS). The
purpose of this extension study was to investigate potential crosstalk between plasma CPB [total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C) and apolipoproteins (Apo) ApoA-I, ApoAII,
ApoB, ApoC-II and ApoE] and hemostasis inhibitors [heparin cofactor-II (HCII), protein C (PC), protein S (PS), thrombomodulin, ADAMTS13 and PAI-1] in a cohort of 127 MS patients, and 40 healthy individuals (HI). The associations were assessed
with regressions. In MS patients, HCII was positively associated with TC, LDL-C, HDL-C and ApoA-I (p=0.028, 0.027, 0.002 and 0.027, respectively) but negatively associated with ApoCII (p=0.018). PC was positively associated with ApoC-II (p=0.001) and ApoB (p=0.016) whereas PS was associated with TC (p=0.024) and ApoE (p=0.003) in MS. The ApoC-II associations were not observed in HI. The negative association between
ApoC-II and HCll was an exception amongst other positive associations between CPB and hemostasis inhibitors in MS. CPB do not modulate the PC associations with neurodegeneration in MS
Follicular fluid high density lipoprotein-associated micronutrient levels are associated with embryo fragmentation during IVF
To investigate whether follicular fluid lipid-soluble micronutrients are associated with embryo morphology parameters during IVF.
Follicle fluid and oocytes were obtained prospectively from 81 women. Embryo morphology parameters were used as surrogate markers of oocyte health. HDL lipids and lipid-soluble micronutrients were analyzed by high-pressure liquid chromatography. Non-parametric bi-variate analysis and multivariable ordinal logistic regression models were employed to examine associations between biochemical and embryo morphology parameters.
Follicular fluid HDL cholesterol (râ=ââ0.47, pâ<â0.01), α-tocopherol (râ=ââ0.41, pâ<â0.01), ÎŽ-tocopherol (râ=ââ0.38, pâ<â0.05) and ÎČ-cryptoxanthine (râ=ââ0.42, pâ<â0.01) are negatively correlated with embryo fragmentation. Ordinal logistic regression models indicate that a 0.1 Όmol/L increase in ÎČ-cryptoxanthine, adjusted for Îł-tocopherol, is associated with a 75% decrease in the cumulative odds of higher embryo fragmentation (pâ=â0.010).
Follicular fluid HDL micronutrients may play an important role in the development of the human oocyte as evident by embryo fragmentation during IVF
Positive Relationship between Total Antioxidant Status and Chemokines Observed in Adults
Objective. Human evidence is limited regarding the interaction between oxidative stress biomarkers and chemokines, especially in a population of adults without overt clinical disease. The current study aims to examine the possible relationships of antioxidant and lipid peroxidation markers with several chemokines in adults. Methods. We assessed cross-sectional associations of total antioxidant status (TAS) and two lipid peroxidation markers malondialdehyde (MDA) and thiobarbituric acid reactive substances (TBARS) with a suite of serum chemokines, including CXCL-1 (GRO-α), CXCL-8 (IL-8), CXCL-10 (IP-10), CCL-2 (MCP-1), CCL-5 (RANTES), CCL-8 (MCP-2), CCL-11 (Eotaxin-1), and CCL-17 (TARC), among 104 Chinese adults without serious preexisting clinical conditions in Beijing before 2008 Olympics. Results. TAS showed significantly positive correlations with MCP-1 (r=0.15751, P=0.0014), MCP-2 (r=0.3721, P=0.0001), Eotaxin-1 (r=0.39598, P<0.0001), and TARC (r=0.27149, P=0.0053). The positive correlations remained unchanged after controlling for age, sex, body mass index, smoking, and alcohol drinking status. No associations were found between any of the chemokines measured in this study and MDA or TBARS. Similar patterns were observed when the analyses were limited to nonsmokers. Conclusion. Total antioxidant status is positively associated with several chemokines in this adult population
Association Between Metabolic Syndrome and Periodontal Disease Measures in Postmenopausal Women: The Buffalo OsteoPerio Study
Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/141377/1/jper1489.pd
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