1,516 research outputs found
The Higgs Potential in the Type II Seesaw Model
We perform in the type II seesaw setting, a detailed study of the dynamical
features of the corresponding general renormalizable doublet/triplet Higgs
potential that depends on five dimensionless couplings and two mass parameters
after spontaneous symmetry breaking, and highlight the implications for the
Higgs phenomenology. In particular, we determine i) the complete set of
tree-level unitarity constraints on the couplings of the potential and ii) the
exact tree-level {\sl all directions} boundedness from below constraints on
these couplings. When combined, these constraints delineate precisely the
theoretically allowed parameter space domain within our perturbative
approximation. Among the seven physical Higgs states of this model, the mass of
the lighter (heavier) CP-even state h0 (H0) will always satisfy a theoretical
upper (lower) bound that is reached for a critical value mu_c of mu (the mass
parameter controlling triple couplings among the doublet/triplet Higgses).
Saturating the unitarity bounds we find m_h0 < {\cal O}(0.7 - 1 TeV), while the
upper bound for the remaining Higgses lies in the several tens of TeV. However,
the actual masses can be much lighter. We identify two regimes corresponding to
mu > mu_c and mu < mu_c. In the first regime the Higgs sector is typically very
heavy and only h0 that becomes SM-like could be accessible to the LHC. In
contrast, in the second regime, somewhat overlooked in the literature, most of
the Higgs sector is light. In particular the heaviest state H0 becomes SM-like,
the lighter states being the CP-odd Higgs, the (doubly) charged Higgses and a
decoupled h0, possibly leading to a distinctive phenomenology at the colliders.Comment: 55 pages, 9 figures, no major changes, references added, a comment
added to sec 3.1, typos correcte
Exploitation of nitric oxide donors to control bacterial adhesion on ready‐to‐eat vegetables and dispersal of pathogenic biofilm from polypropylene
Background
Nitric oxide (NO) donors have been used to control biofilm formation. NO can be delivered in situ using organic carriers and act as a signaling molecule. Cells exposed to NO shift from biofilm to the planktonic state and are better exposed to the action of disinfectants. In this study, we investigate the capability of the NO donors molsidomine, MAHAMA NONOate, NO‐aspirin and diethylamine NONOate to act as anti‐adhesion agents on ready‐to‐eat vegetables, as well as dispersants to a number of pathogenic biofilms on plastic.
Results
Our results showed that 10pM molsidomine reduced the attachment of Salmonella enterica sv Typhimurium 14 028 to pea shoots and coriander leaves of about 0.5 Log(CFU/leaf) when compared with untreated control. The association of 10 pM molsidomine with 0.006% H2O2 showed a synergistic effect, obtaining a significant reduction in cell collection on the surface of the vegetable of about 1 Log(CFU/leaf). Similar results were obtained for MAHMA NONOate.
We also showed that the association of diethylamine NONOate at 10 mM and 10pM with the quaternary ammonium compound diquat bromide improves the effectiveness of biofilm dispersal by 50% when compared with the donor alone.
Conclusions
Our findings reveal the dual role of NO compounds in biofilm control. Molsidomine, MAHMA NONOate and diethylamine NONOate are good candidates in either preventing biofilm formation or dispersing biofilm, especially when used in conjunction with disinfectants. NO compounds have the potential to be developed into tool‐kit for pro‐active practices for GAPs, HACCP and Cleaning‐in‐place (CIP) protocols in industrial settings where washing is routinely applied.
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Maternal and neonatal complications of fetal macrosomia: cohort study
Objective: To estimate risks of maternal and neonatal complications in pregnancies with macrosomia.
Method: This was a retrospective cohort study undertaken at a large maternity unit in United Kingdom between January 2009-December 2016. We compared the incidence of complications in pregnancies with macrosomia, defined by birthweight (BW)>4,000 g and severe macrosomia with BW>4,500 g, to those in pregnancies with normal BW 2,500-4,000 g. Regression analysis was undertaken to determine odds ratios (OR) [95% confidence interval (CI)] for pregnancy complications in macrosomic compared to normal BW group.
Results: The study population of 35,548 pregnancies included 4,522 (12.7%) with macrosomia, 643 (1.8%) with severe macrosomia and 31,026 (87.3%) with normal BW. In macrosomia group, adjusted OR was 3.07 (95%CI:1.64,2.01) for cesarean section for failure to progress, 2.40 (95%CI:1.95,2.96) for post-partum haemorrhage, 2.29 (95%CI:1.86,2.82) for sphincter injury, 10.37 (95%CI:8.57,12.55) for shoulder dystocia, 28.48 (95%CI:8.94,90.67) for brachial plexus injury, 32.33 (95%CI:3.76,278.15) for birth fractures and 4.40 (95%CI:2.20,8.82) for hypoxic-ischemic encephalopathy. The respective values for severe macrosomia were 4.32 (95%CI:3.05,6.13), 2.93 (95%CI:1.93,4.44), 3.12 (95%CI:1.92,5.08), 28.74 (95%CI:20.75,39.79), 73.92 (95%CI:15.05,363.16), 87.17 (95%CI:7.72,984.96) and 13.77 (95%CI: 5.16,36.75).
Conclusion: Macrosomia is associated with serious adverse perinatal outcomes. This study provides accurate estimates of risks to aid in pregnancy management
GreenSTEM’s microbe technology is an efficient, effective, and affordable way to clean up fuel and chemical spills
Non-Peer ReviewedPetroleum hydrocarbons are used as fuel and for chemical synthesis. If spilled, fuels and chemicals poison our soil and water, causing local environmental disasters. Bioremediation uses organisms to clean up (remediate) pollutants. We have isolated and characterized microbe strains from contaminated sites, and use them to remediate contaminated sites elsewhere. We identify our strains using their DNA sequences and their appearance. Some microbes, called fungal endophytes, form symbioses, in other words metabolic partnerships between a plant and a fungus. These symbioses have been shown to stimulate plant growth and root formation, even on contaminated soil. Surprisingly, some of our other microbes can degrade hydrocarbons underground, without plants. GreenSTEM has powerful technology: we use native microbes to degrade hydrocarbons and chemicals as they grow on the contaminants as food. Based on our progress to date with fuels and other chemicals, we anticipate isolating new strains specific for other intractable toxins
Triple domestic heat recovery system: thermal modeling and parametric study
International audienc
Domestic thermoelectric cogeneration drying system: Thermal modeling and case study
The demand for reducing fuel consumption and mitigating exhaust fumes accountable for the greenhouse effect push toward developing efficient energy recovery systems. Optimizing the heat recovery process can be achieved by adding multi-recovery stages. In this frame, the present work suggests a new multi-stage recovery system for heating water and air and generating electricity. The concept of the system is applied to the exhaust gases of a chimney. A complete thermal modeling of the system is drawn. Then a case study is carried out for three different fed fuels (diesel, coal, wood). The results show that when diesel is used water temperature achieved 351 K and 240 W electric power is generated. Moreover, a 0.16 m2 heat recovery heat exchanger area is required to heat air to 363 K at an air flow rate of 0.0076 kg/s. Such system can recover up to 84% of the energy lost to the environment when wood is utilized as a fed fuel
Study on Quality of Pair Distribution Function for Direct Space Approach of Structure Investigation
Study of the structure characteristics of solid materials is a key for development of technological applications. Potential of direct space approach for structure determination and refinement using powder X-ray diffraction data depend on the quality of pair distribution function (PDF) plot. So, the effect of data collection conditions and diffractogram characteristics on the quality of PDF plot has been investigated in detail. In addition, errors and possible tolerance have been estimated. Some parameters affect only either the X-ray diffractogram or PDF plots and others affect both. Considering the errors and tolerance, direct space approach can be confidently used for structure refinement, where the error did not exceed 10.0 % for inter-atomic radial distance longer than » 2.0 ? and 5.0 % for longer than » 4.0 ?, which is accepted for structure refinement. As tolerance is considered, every time the value of the lattice parameter is changed to smaller or larger than the correct value (+ 8.0 %), it comes back to the initial correct one. Although, advanced synchrotron radiation shows better data, conventional source can be used successfully for structure investigation applying direct space approach
SOLUBILITY OF SUNFLOWER PROTEINS AND GEL FILTRATION CHROMATOGRAPHY OF THEIR WATER-SOLUBLE FRACTIONS
Bahr El-Baqar drain system / Egypt environmental studies on water quality. Part I: Bilbeis drain / Bahr El-Baqar drain
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