374 research outputs found
Scalar Asymptotic Charges and Dual Large Gauge Transformations
In recent years soft factorization theorems in scattering amplitudes have
been reinterpreted as conservation laws of asymptotic charges. In gauge,
gravity, and higher spin theories the asymptotic charges can be understood as
canonical generators of large gauge symmetries. Such a symmetry interpretation
has been so far missing for scalar soft theorems. We remedy this situation by
treating the massless scalar field in terms of a dual two-form gauge field. We
show that the asymptotic charges associated to the scalar soft theorem can be
understood as generators of large gauge transformations of the dual two-form
field.
The dual picture introduces two new puzzles: the charges have very unexpected
Poisson brackets with the fields, and the monopole term does not always have a
dual gauge transformation interpretation. We find analogs of these two
properties in the Kramers-Wannier duality on a finite lattice, indicating that
the free scalar theory has new edge modes at infinity that canonically commute
with all the bulk degrees of freedom.Comment: 16 pages, 2 figure
Dynamical Surface Gravity in Spherically Symmetric Black Hole Formation
We study dynamical surface gravity in a general spherically symmetric setting
using Painlev\'{e}-Gullstrand (PG) coordinates. Our analysis includes several
definitions that have been proposed in the past as well as two new definitions
adapted to PG coordinates. Various properties are considered, including general
covariance, value at extremality, locality and static limit. We illustrate with
specific examples of "dirty" black holes that even for spacetimes possessing a
global timelike Killing vector, local definitions of surface gravity can differ
substantially from "non-local" ones that require an asymptotic normalization
condition. Finally, we present numerical calculations of dynamical surface
gravity for black hole formation via spherically symmetric scalar field
collapse. Our results highlight the differences between the various definitions
in a dynamical setting and provide further insight into the distinction between
local and non-local definitions of surface gravity.Comment: Final version to appear in Phys. Rev. D. Slight name change, further
improvements to numerics and presentation, 25 pages, 7 figure
Color Fields on the Light-Shell
We study the classical color radiation from very high energy collisions that
produce colored particles. In the extreme high energy limit, the classical
color fields are confined to a light-shell expanding at and are associated
with a non-linear -model on the 2D light-shell with specific symmetry
breaking terms. We argue that the quantum version of this picture exhibits
asymptotic freedom and may be a useful starting point for an effective
light-shell theory of the structure between the jets at a very high energy
collider.Comment: 11 pages, no figure
Revisiting the quantum scalar field in spherically symmetric quantum gravity
We extend previous results in spherically symmetric gravitational systems
coupled with a massless scalar field within the loop quantum gravity framework.
As starting point, we take the Schwarzschild spacetime. The results presented
here rely on the uniform discretization method. We are able to minimize the
associated discrete master constraint using a variational method. The trial
state for the vacuum consists of a direct product of a Fock vacuum for the
matter part and a Gaussian centered around the classical Schwarzschild
solution. This paper follows the line of research presented by Gambini, Pullin
and Rastgoo and a comparison between their result and the one given in this
work is made.Comment: 16 page
Novel anticancer drug 5h-pyro[3,2-a] phenoxazin-5-one (PPH) regulates lncRNA HOTAIR and HOXC genes in human MCF-7 cells
Breast cancer in women is the second most commonly cancer, after skin cancer. The percentage of mortality risk for breast cancer is 1 in 37 women (2.7%), which makes breast cancer represent the second cause of cancer death in women. Recently, new research based on previously published work in systemic chemotherapy and endocrine therapy field, have improved the incidence rates. The quinonic nucleus is common to many natural and synthetic products associated with anticancer and antibacterial activities, these compounds are typically DNA-intercalating agents. The Class I Homeobox genes (HOX in human and hox in mouse) control embryonic development and specific determination of positional identity anteroposterior axis of the human body. The HOX genes, are 39 transcription factors related to morphological, physiological disease. It has been demonstrated that any deregulation into the network is able to induce neoplastic transformation. Particularly, HOXC locus collaborating with lncRNA HOTAIR play a key role in breast cancer. In this study, our group evaluated the chemical and metabolic stability of new anticancer molecule 5H-pyro[3,2-a] phenoxazin-5-one (PPH). In a recent paper, we have already demonstrated that a new and potent anticancer synthetic iminoquinone, the 5H-pyrido[3,2-a]phenoxazin-5-one (PPH), is able to inhibit a large number of lymphoblastoid and solid-tumor-derived cells at submicromolar concentrations. Based on our previous research, we decided to analyze the cytotoxic effect and capability of PPH to control the lncRNA HOTAIR and HOXC locus gene expression in human breast cancer cells MCF-7, in order to demonstrate its role like potential new breast cancer antitumor drug
Chemistry meets Industry and Society A creative showcase conference
Buffalo milk contributes to 13% of the world milk production and is abundantly produced in Southern Italy regions. Buffalo milk is appreciated for its nutritive properties and is highly suitable for the manufacturing of wide range of dairy products. Several studies showed many bioactive peptides in different dairy species such as bovine, ovine and caprine milk, but few studies have been conducted on the buffalo dairy products (1). The present work is focused on the identification of bioactive peptides released after in vitro simulated gastrointestinal digestion of protein fraction isolated from buffalo-milk dairy products by ultra- and nanofiltration pilot plant.
The gastrointestinal digests of protein fractions were monitored by RP-UHPLC-DAD, while, the peptide identification was carried out by UHPLC-Orbitrap-based tandem mass spectrometry. 165 peptides were identified in Yoghurt, 152 in Scamorza, 146 in Mozzarella, 136 in Grana and Ricotta and 120 in Ice Cream samples (1). The peptides belong to both buffalo caseins (αs1-, ÎČ-, k-CN) and whey proteins (α-LA, ÎČ-LG).
Six G.I. digests of dairy products were tested in a model of oxidative stress using IEC-6 cells. Among them, buffalo ricotta cheese was the most active. UHPLC-PDA-MS/MS analysis revealed the presence of two abundant ÎČ-lactoglobulin peptides (BRP: YVEELKPTPEGDL, f:60-72 and BRP2: SFNPTQL, f:168-174). To confirm the hypothesized chemical structures and study their specific biological activity, the peptides were synthesized by conventional solid-phase peptide synthesis methods. The antioxidant potential of the identified peptides was then evaluated in a model of hydrogen peroxide induced oxidative stress in IEC-6 cell line. The peptides reduce ROS release and increase nuclear factor (erythroid-derived 2)-like 2 activation and the expression of antioxidant cytoprotective factors such as heme oxygenase 1, NAD(P)H: quinone oxidoreductase 1 and superoxide dismutase (2). The bioavailability of ÎČ-lactoglobulin peptides was evaluated in intestinal transport studies through Caco-2 cell monolayer. Only BRP2 showed equal bi-directional transport and linear permeability, suggesting that it was mainly absorbed through passive diffusion. In addition to its local effects, administration of BPR2 on mice mesenteric arteries counteracts the Angiotensin II-induced vasoconstriction by Nrf2 nuclear translocation, reduction of active form of Ras-related C3 botulinum toxin substrate 1 (Rac1) and NADPH oxidase activity. The analysis at molecular level of treated vessels showed an induction of Nrf2 translocation to nucleus associated with increased expression of MnSOD and Rac1 deactivation.
The data indicate how protein fraction of buffalo ricotta cheese could be an important source of antioxidant compounds, as well as YVEELKPTPEGDL and SFNPTQL peptides could be considered as an âingredientâ for nutraceuticals formulations and functional and personalized foods, in order to prevent the onset of some gastrointestinal pathologies and cardiovascular diseases
Null to time-like infinity Greenâs functions for asymptotic symmetries in Minkowski spacetime
Novel Anticancer Drug 5H-pyro[3,2-a] Phenoxazin-5-one (PPH) Regulates lncRNA HOTAIR and HOXC genes in Human MCF-7 Cells
Breast cancer in women is the second most commonly cancer, after skin cancer. The percentage of mortalityrisk for breast cancer is 1 in 37 women (2.7%), which makes breast cancer represent the second cause of cancerdeath in women. Recently, new research based on previously published work in systemic chemotherapy andendocrine therapy field, have improved the incidence rates. The quinonic nucleus is common to many naturaland synthetic products associated with anticancer and antibacterial activities, these compounds are typicallyDNA-intercalating agents. The Class I Homeobox genes (HOX in human and hox in mouse) control embryonicdevelopment and specific determination of positional identity anteroposterior axis of the human body. The HOXgenes, are 39 transcription factors related to morphological, physiological disease. It has been demonstratedthat any deregulation into the network is able to induce neoplastic transformation. Particularly, HOXC locuscollaborating with lncRNA HOTAIR play a key role in breast cancer.
In this study, our group evaluated the chemical and metabolic stability of new anticancer molecule 5H-pyro[3,2-a] phenoxazin-5-one (PPH). In a recent paper, we have already demonstrated that a new and potent anticancersynthetic iminoquinone, the 5H-pyrido[3,2-a]phenoxazin-5-one (PPH), is able to inhibit a large number oflymphoblastoid and solid-tumor-derived cells at submicromolar concentrations.
Based on our previous research, we decided to analyze the cytotoxic effect and capability of PPH to control thelncRNA HOTAIR and HOXC locus gene expression in human breast cancer cells MCF-7, in order to demonstrateits role like potential new breast cancer antitumor drug
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