Split Dimensional Regularization for the Coulomb Gauge

A new procedure for regularizing Feynman integrals in the noncovariant Coulomb gauge is proposed for Yang-Mills theory. The procedure is based on a variant of dimensional regularization, called split dimensional regularization, which leads to internally consistent, ambiguity-free integrals. It is demonstrated that split dimensional regularization yields a one-loop Yang-Mills self-energy that is nontransverse, but local. Despite the noncovariant nature of the Coulomb gauge, ghosts are necessary in order to satisfy the appropriate Ward/BRS identity. The computed Coulomb-gauge Feynman integrals are applicable to both Abelian and non-Abelian gauge models. PACS: 11.15, 12.38.CComment: 19 pages, 2 figures, 1 table, 72 references. This Replaced version clarifies why the Coulomb gauge requires a new type of regularization, and why our new regularization is compatible with Wick rotation. Results and table of integrals are unchanged. To appear in Nuclear Physics

Effectiveness of Ayurveda in Nephrotic Syndrome w.s.r. to Vrikkajanya Sankarya: An Evidence-Based Case Study

As far as Nephrotic Syndrome is considered, it mainly manifests with major protein loss through urine as a cardinal symptom which can be associated with Vrikkajanya Vikara, which is referred to as a type of renal disorder/Vrikka Vikara. A 24-year-old female presented with left lumbar pain, pus in urine, burning micturition, and proteinuria (3+). On the basis of Dosha assessment, Rasayana, Stambhaka, and Mutral Dravyas like Gokhru, Giloy, Chandraprabha Vati, and Ushirasava, including some dietary modifications, were prescribed for two months. Mild improvement was seen in follow ups. This case signifies the importance of early diagnosis and planned ayurvedic interventions in NS to take preventive measures and to keep away from complications and to improve quality of life

Precise Payload Delivery via Unmanned Aerial Vehicles: An Approach Using Object Detection Algorithms

Recent years have seen tremendous advancements in the area of autonomous payload delivery via unmanned aerial vehicles, or drones. However, most of these works involve delivering the payload at a predetermined location using its GPS coordinates. By relying on GPS coordinates for navigation, the precision of payload delivery is restricted to the accuracy of the GPS network and the availability and strength of the GPS connection, which may be severely restricted by the weather condition at the time and place of operation. In this work we describe the development of a micro-class UAV and propose a novel navigation method that improves the accuracy of conventional navigation methods by incorporating a deep-learning-based computer vision approach to identify and precisely align the UAV with a target marked at the payload delivery position. This proposed method achieves a 500% increase in average horizontal precision over conventional GPS-based approaches.Comment: Second International Conference on Artificial Intelligence, Computational Electronics and Communication System (AICECS 2023

A Comprehensive Review on the Role of Bioremediation in Heavy Metal Contamination

Heavy metal contamination, along with other pollutants, presents significant environmental hazards. These substances not only endanger human health but also disrupt natural ecosystem. Bioremediation emerges as a sustainable and economically viable approach to tackling pollution. It harnesses the capabilities of microorganisms, plants, and their enzymes to degrade or neutralize pollutants. This paper categorizes bioremediation into two primary types: ex-situ and in-situ. Ex-situ bioremediation treats contaminated material away from its original location, while in-situ bioremediation addresses contamination directly at the site. This paper also explores how microbes tolerate heavy metals through various mechanisms. These mechanisms encompass extracellular barriers, efflux pumps, enzymatic reduction, and intracellular sequestration. Extracellular barriers function to block the entry of metals into the cell, whereas efflux pumps work actively to expel metals from the cell. Enzymatic reduction facilitates the conversion of metals into less harmful forms, while intracellular sequestration involves storing metals within the cell. Moreover, the paper examines diverse applications of bioremediation in environmental restoration. These applications encompass natural attenuation, enhanced reductive dechlorination, sewage treatment, bioleaching, biosorption, constructed wetlands, biostimulation, and bioaugmentation. This paper emphasizes the need for further research to optimize bioremediation technologies for broader real-world environmental management applications

The C313Y Piedmontese mutation decreases myostatin covalent dimerisation and stability

<p>Abstract</p> <p>Background</p> <p>Myostatin is a key negative regulator of muscle growth and development, whose activity has important implications for the treatment of muscle wastage disorders. Piedmontese cattle display a double-muscled phenotype associated with the expression of C313Y mutant myostatin. <it>In vivo</it>, C313Y myostatin is proteolytically processed, exported and circulated extracellularly but fails to correctly regulate muscle growth. The C313Y mutation removes the C313-containing disulphide bond, an integral part of the characteristic TGF-β cystine-knot structural motif.</p> <p>Results</p> <p>Here we present <it>in vitro </it>analysis of the structure and stability of the C313Y myostatin protein that reveals significantly decreased covalent dimerisation for C313Y myostatin accompanied by a loss of structural stability compared to wild type. The C313Y myostatin growth factor, processed from full length precursor protein, fails to inhibit C2C12 myoblast proliferation in contrast to wild type myostatin. Although structural modeling shows the substitution of tyrosine causes structural perturbation, biochemical analysis of additional disulphide mutants, C313A and C374A, indicates that an intact cystine-knot motif is a major determinant in myostatin growth factor stability and covalent dimerisation.</p> <p>Conclusions</p> <p>This research shows that the cystine-knot structure is important for myostatin dimerisation and stability, and that disruption of this structural motif perturbs myostatin signaling.</p

Acute-Phase-HDL Remodeling by Heparan Sulfate Generates a Novel Lipoprotein with Exceptional Cholesterol Efflux Activity from Macrophages

During episodes of acute-inflammation high-density lipoproteins (HDL), the carrier of so-called good cholesterol, experiences a major change in apolipoprotein composition and becomes acute-phase HDL (AP-HDL). This altered, but physiologically important, HDL has an increased binding affinity for macrophages that is dependent on cell surface heparan sulfate (HS). While exploring the properties of AP-HDL∶HS interactions we discovered that HS caused significant remodeling of AP-HDL. The physical nature of this change in structure and its potential importance for cholesterol efflux from cholesterol-loaded macrophages was therefore investigated. In the presence of heparin, or HS, AP-HDL solutions at pH 5.2 became turbid within minutes. Analysis by centrifugation and gel electrophoresis indicated that AP-HDL was remodeled generating novel lipid poor particles composed only of apolipoprotein AI, which we designate β2. This remodeling is dependent on pH, glycosaminoglycan type, is promoted by Ca2+ and is independent of protease or lipase activity. Compared to HDL and AP-HDL, remodeled AP-HDL (S-HDL-SAA), containing β2 particles, demonstrated a 3-fold greater cholesterol efflux activity from cholesterol-loaded macrophage. Because the identified conditions causing this change in AP-HDL structure and function can exist physiologically at the surface of the macrophage, or in its endosomes, we postulate that AP-HDL contains latent functionalities that become apparent and active when it associates with macrophage cell surface/endosomal HS. In this way initial steps in the reverse cholesterol transport pathway are focused at sites of injury to mobilize cholesterol from macrophages that are actively participating in the phagocytosis of damaged membranes rich in cholesterol. The mechanism may also be of relevance to aspects of atherogenesis

Pressure perturbation calorimetry of apolipoproteins in solution and in model lipoproteins

High-density lipoproteins (HDL) are complexes of lipids and proteins (termed apolipoproteins) that remove cell cholesterol and protect from atherosclerosis. Apolipoproteins contain amphipathic α-helices that have high content (≥1/3) and distinct distribution of charged and apolar residues, adopt molten globule-like conformations in solution, and bind to lipid surfaces. We report the first pressure perturbation calorimetry (PPC) study of apolipoproteins. In solution, the main HDL protein, apoA-I, shows relatively large volume contraction, ΔV(unf)=-0.33%, and an apparent reduction in thermal expansivity upon unfolding, Δα(unf)≤0, which has not been observed in other proteins. We propose that these values are dominated by increased charged residue hydration upon α-helical unfolding, which may result from disruption of multiple salt bridges. At 5°C, apoA-I shows large thermal expansion coefficient, α(5°) = 15·10(-4) K(-1), that rapidly declines upon heating from 5-40°C, α(40°)-α(5°)=-4·10(-4) K(-1); apolipoprotein C-I shows similar values of α(5°) and α(40°). These values are larger than in globular proteins. They indicate dominant effect of charged residue hydration, which may modulate functional apolipoprotein interactions with a broad range of their protein and lipid ligands. The first PPC analysis of a protein-lipid complex is reported, which focuses on the chain melting transition in model HDL containing apoA-I or apoC-I, dimyristoyl phosphatidylcholine, and 0–20% cholesterol. The results may provide new insights into volumetric properties of HDL that modulate metabolic lipoprotein remodeling during cholesterol transport

Removal of methylene blue from wastewater under a low power irradiation source by Zn, Mn co-doped TiO₂ photocatalysts

Hazardous methylene blue dye from wastewater can be removed by a Zn–Mn co-doped photocatalyst under a very low power irradiation source, where 1.0 at% Zn, Mn doped TiO2 provides the maximum degradation of this pollutant.</p