Celestial amplitudes from UV to IR Arkani-Hamed, N.; Pate, M.; Raclariu, A.-M. ...
The journal of high energy physics,
08/2021, Letnik:
2021, Številka:
8
Journal Article
Recenzirano
Odprti dostop
A
bstract
Celestial amplitudes represent 4D scattering of particles in boost, rather than the usual energy-momentum, eigenstates and hence are sensitive to both UV and IR physics. We show that known ...UV and IR properties of quantum gravity translate into powerful constraints on the analytic structure of celestial amplitudes. For example the soft UV behavior of quantum gravity is shown to imply that the exact four-particle scattering amplitude is meromorphic in the complex boost weight plane with poles confined to even integers on the negative real axis. Would-be poles on the positive real axis from UV asymptotics are shown to be erased by a flat space analog of the AdS resolution of the bulk point singularity. The residues of the poles on the negative axis are identified with operator coefficients in the IR effective action. Far along the real positive axis, the scattering is argued to grow exponentially according to the black hole area law. Exclusive amplitudes are shown to simply factorize into conformally hard and conformally soft factors. The soft factor contains all IR divergences and is given by a celestial current algebra correlator of Goldstone bosons from spontaneously broken asymptotic symmetries. The hard factor describes the scattering of hard particles together with the boost-eigenstate clouds of soft photons or gravitons required by asymptotic symmetries. These provide an IR safe
S
-matrix for the scattering of hard particles.
Background: Inflammatory bowel disease is an autoimmune disease that affects the gut.
larvae (E/S Ags) loaded on calcium-benzene-1,3,5-tricarboxylate metal-organic frameworks (Ca-BTC MOFs) were ...tested to determine whether they might prevent or cure acetic acid-induced murine colitis. Methods:
larvae E/S Ags/Ca-BTC MOFs were used in prophylactic and therapeutic groups to either precede or follow the development of murine colitis. On the seventh day after colitis, mice were slaughtered. The effect of our target antigens on the progress of the colitis was evaluated using a variety of measures, including survival rate, disease activity index, colon weight/bodyweight, colon weight/length) ratios, and ratings for macroscopic and microscopic colon damage. The levels of inflammatory cytokines (interferon-γ and interleukin-4), oxidative stress marker malondialdehyde, and glutathione peroxidase in serum samples were evaluated. Foxp3 T-reg expression was carried out in colonic and splenic tissues. Results:
larvae E/S Ags/Ca-BTC MOFs were the most effective in alleviating severe inflammation in murine colitis. The survival rate, disease activity index score, colon weight/length and colon weight/bodyweight ratios, and gross and microscopic colon damage scores have all considerably improved. A large decrease in proinflammatory cytokine (interferon-γ) and oxidative stress marker (malondialdehyde) expression and a significant increase in interleukin-4 and glutathione peroxidase expression were obtained. The expression of Foxp3+ Treg cells was elevated in colonic and splenic tissues. Conclusion:
larvae E/S Ags/Ca-BTC MOFs had the highest anti-inflammatory, antioxidant, and cytoprotective capabilities against murine colitis and might be used to develop new preventative and treatment strategies.
The objective of this paper was the investigation of vibration characteristics of both nonlinear symmetric power and sigmoid functionally graded nonlocal nanobeams. The volume fractions of metal and ...ceramic are assumed to be distributed through a beam thickness by sigmoid law distribution and symmetric power function. Structures with symmetric distribution with mid-plane such as ceramic–metal–ceramic and metal–ceramic–metal are proposed. Nonlocal differential Eringen’s elasticity is exploited to incorporate size dependency of nanobeam. The kinematic relations of Euler–Bernoulli beam are proposed, with the assumption of a small strain. A nonlocal equation of motion of nanobeam is derived by using principle of virtual work and then discretized by finite element method to obtain numerical solution. Numerical results show the effects of the function distribution, gradient index and nonlocal parameter on natural frequencies of macro- and nanobeam. This model is helpful in the mechanical design of nanoelectromechanical systems manufactured from FGM.
Despite the considerable efforts reported so far to enhance seed priming, novel ideas are still needed to be suggested to this sustainable sector of agri-seed industry. This could be the first study ...addressing the effect of nitric oxide (NO) under open field conditions. The impacts of seed redox-priming using sodium nitroprusside (SNP) and osmo-priming with calcium chloride (CaCl.sub.2), both applied individually or successively, were investigated under salinity stress conditions on wheat plants (Triticum aestivum L.). Various parameters, including water relations, growth, yield, photosynthetic pigments, and antioxidant activities (enzymatic and non-enzymatic), were recorded to assess the outcomes of these priming agents on mitigating the negative impacts of salinity stress on wheat plants. Water consumptive use (ETa) and irrigation water applied (IWA) decreased with seeds priming. Successive priming with SNP + CaCl.sub.2 induced the greatest values of crop water productivity (CWP), irrigation water productivity (IWP), seed index, grain yield and grain nitrogen content.Under salinity stress, the dry weight of plants was decreased. However, hydro-priming and successive chemical priming agents using combinations of calcium chloride and sodium nitroprusside (CaCl.sub.2 + SNP & SNP + CaCl.sub.2) preserved growth under salinity stress.Individual priming with sodium nitroprusside (SNP) and calcium chloride (CaCl.sub.2) resulted in the lowest recorded content of sodium in the shoot, with a value of 2 ppm. On the other hand, successive priming using CaCl.sub.2 + SNP or SNP + CaCl.sub.2 induced the contents of potassium in the shoot, with values of 40 ppm and 39 ppm, respectively. Malondialdehyde decreased in shoot significantly withapplicationof priming agents. Successive priming with CaCl.sub.2 + SNP induced the highest proline contents in shoot (6 microg/ g FW). The highest value of phenolics and total antioxidants contents in shoot were recorded under successive priming using CaCl.sub.2 + SNP and SNP + CaCl.sub.2.Priming agents improved the activities of ascorbate peroxidase and catalase enzymes. The successive priming improved water relations (ETa, IWA, CWP and IWP) and wheat growth and productivity under salinity stress more than individual priming treatments.
I suggest an irregular aperture and calculate the impulse response, or the point spread function (PSF) corresponding to this aperture. In addition, I calculated the PSF in the case of rotated ...irregular apertures. Secondly, I apply these irregular apertures to the confocal scanning laser microscope (CSLM). I obtained the images using the CSLM provided with irregular apertures and compared them with the case of uniform circular apertures. Finally, I differentiate speckle images that were obtained using different orientations of the irregular aperture. Then, I reconstructed the irregular aperture at different orientations from the speckle pattern.
Antikoch and highly active anti-retroviral therapy are effective drugs in the management of tuberculosis and Human Immunodeficiency Virus, respectively. However, these cocktails have been ...independently associated with the aetiopathogenesis of metabolic syndrome. This study investigated whether or not the co-administration of antikoch and anti-retroviral, as seen in tuberculosis/Human Immunodeficiency Virus co-infection, will produce a similar effect. Also, it evaluated the role of glutathione and adenine deaminase/xanthine oxidase/uric acid signaling in antikoch/anti-retroviral-induced cardiometabolic dysfunction.
Male rats of Wistar strain were randomized into four groups: the control, which had 0.5 mL of distilled water as a vehicle, anti-Koch-treated rats that were administered a cocktail of anti-Koch, HAART-treated rats that had a combination of anti-retroviral drugs, and anti-Koch + HAART-treated rats that had treatments as anti-Koch-treated and HAART-treated rats. The treatment was once daily and lasted for eight weeks. One way-analysis of variance followed by Tukey's posthoc test was used to test for significance and pairwise comparisons respectively.
Although no changes in body weight gain and cardiac weight were noted, it was found that antikoch and/or HAART caused insulin resistance and elevated blood glucose level. In addition, antikoch and/or HAART led to dyslipidaemia, increased atherogenic indices, and elevated cardiac injury markers. These were accompanied by increased plasma and cardiac concentrations of malondialdehyde and nitric oxide, C-reactive protein, and myeloperoxidase activity, as well as suppressed activities of glutathione peroxidase and glutathione-S-transferase, and a fall in reduced glutathione level. The observed alterations were more pronounced in animals that received a combination of antikoch and HAART.
This study provides the first evidence that antikoch and/or HAART induce cardiometabolic dysfunction via glutathione suppression and up-regulation of adenine deaminase/xanthine oxidase/uric acid-dependent oxidative stress and inflammatory response. These events were associated with dyslipidaemia and increased atherogenic indices. This infers that regular monitoring of glucose level, insulin sensitivity, lipid profile, and oxido-inflammatory markers is important in patients on antikoch and/or HAART for prompt diagnosis and management of cardiometabolic disorder if it ensues.
The successful early diagnosis of brain tumors plays a major role in improving the treatment outcomes and thus improving patient survival. Manually evaluating the numerous magnetic resonance imaging ...(MRI) images produced routinely in the clinic is a difficult process. Thus, there is a crucial need for computer-aided methods with better accuracy for early tumor diagnosis. Computer-aided brain tumor diagnosis from MRI images consists of tumor detection, segmentation, and classification processes. Over the past few years, many studies have focused on traditional or classical machine learning techniques for brain tumor diagnosis. Recently, interest has developed in using deep learning techniques for diagnosing brain tumors with better accuracy and robustness. This study presents a comprehensive review of traditional machine learning techniques and evolving deep learning techniques for brain tumor diagnosis. This review paper identifies the key achievements reflected in the performance measurement metrics of the applied algorithms in the three diagnosis processes. In addition, this study discusses the key findings and draws attention to the lessons learned as a roadmap for future research.
In a computing context, cybersecurity is undergoing massive shifts in technology and its operations in recent days, and data science is driving the change. Extracting
security incident patterns
or ...insights from cybersecurity data and building corresponding
data-driven model
, is the key to make a security system automated and intelligent. To understand and analyze the actual phenomena with data, various scientific methods, machine learning techniques, processes, and systems are used, which is commonly known as data science. In this paper, we focus and briefly discuss on
cybersecurity data science
, where the data is being gathered from relevant cybersecurity sources, and the analytics complement the
latest data-driven patterns
for providing more effective security solutions. The concept of cybersecurity data science allows making the computing process more actionable and intelligent as compared to traditional ones in the domain of cybersecurity. We then discuss and summarize a number of associated
research issues and future directions
. Furthermore, we provide a
machine learning
based
multi-layered framework
for the purpose of cybersecurity modeling. Overall, our goal is not only to discuss cybersecurity data science and relevant methods but also to focus the applicability towards data-driven intelligent decision making for protecting the systems from cyber-attacks.
We suggested the hexagonal aperture to compute the point spread function (PSF) by making use of scalar diffraction theory and Fourier operations. We have got an analytical formula for the PSF ...corresponding to the hexagonal aperture. We compared the PSF results with that computed by applying the Fast Fourier transform. Hence, we have got the spatial resolution from the cut-off corresponding to the PSF plot using the hexagonal aperture. In addition, we gave an application of hexagonal and circular apertures using the CSLM. Finally, we have got the reconstructed images using the CSLM provided with circular and hexagonal apertures.
We designed an obstructed Cauchy filter to improve the microscope resolution, and we calculated the point spread function (PSF) considering the Fourier transform operation deduced from the known ...Fraunhofer diffraction. Then, we computed the coherent transfer function (CTF) from the autocorrelation of the modulated Cauchy aperture. We applied the modulated Cauchy pupils to a confocal scanning laser microscope (CSLM) and examined the obtained images. We compared the images with the case of uniform circular apertures. We used the MATLAB code to make all the images and plots.
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