Microplastic pollution is one of the emerging threats across the globe and is becoming a topic of intense study for environmental researchers. At present, almost all of the world’s oceans and seas ...are contaminated with microplastics but the Mediterranean Sea has been recognized as a target hotspot of the world as the microplastic concentration in this region is approximately four times greater than the North Pacific Ocean. Because of the distinguishing semi-enclosed morphology of the Mediterranean Sea, and different plastic waste generating activities originating from surrounding countries the Mediterranean Sea is highly vulnerable to microplastic pollution. Different plastic families have been reported in the Mediterranean Sea and the Physico-chemical features of these plastic polymers play an important role in the interactions between these plastic particles and other organic matter in the water bodies. The ingestion of microplastics by marine animals is an issue of concern as microplastic acts as vectors for other harmful pollutants adsorbed onto their surface. This review provides a detailed discussion on the persistence of microplastics in the Mediterranean Sea that have been identified in surface water and also in sediments and deep sea-floor. Various sources of these synthetic materials and the intensity of low and high-density polymers pollution in the Mediterranean Sea have also been discussed. This review also focuses on the threatened species in the Mediterranean Sea and the fate of the plastisphere community in its ecosystem. In the end, we highlight a series of important regulations and policies adopted by Mediterranean countries to control and manage the microplastic pollution in this region.
A heterogeneous catalyst is a backbone of modern sustainable green industries; and understanding the relationship between its structure and properties is the key for its advancement. Recently, many ...upscaling synthesis strategies for the development of a variety of respectable control atomically precise heterogeneous catalysts are reported and explored for various important applications in catalysis for energy and environmental remediation. Precise atomic‐scale control of catalysts has allowed to significantly increase activity, selectivity, and in some cases stability. This approach has proved to be relevant in various energy and environmental related technologies such as fuel cell, chemical reactors for organic synthesis, and environmental remediation. Therefore, this review aims to critically analyze the recent progress on single‐atom catalysts (SACs) application in oxygen reduction reaction, oxygen evolution reaction, hydrogen evolution reaction, and chemical and/or electrochemical organic transformations. Finally, opportunities that may open up in the future are summarized, along with suggesting new applications for possible exploitation of SACs.
Single‐atom catalysts (SACs) can provide an efficient and highly active catalyst for various electrochemical applications. SACs maximize the utilization of the metal active sites, improve catalytic activity, and selectivity. This review highlights the recent progress on their utilization for various electrochemical applications such as oxygen reduction reaction, oxygen evolution reaction, hydrogen evolution reaction, organic electrochemical transformation, and organic transformation.
Understanding the unique properties of water still represents a significant challenge for theory and experiment. Computer simulations by molecular dynamics require a reliable description of the ...atomic interactions, and in recent decades countless water potentials have been reported in the literature. Still, most of these potentials contain significant approximations, for instance a frozen internal structure of the individual water monomers. Artificial neural networks (NNs) offer a promising way for the construction of very accurate potential-energy surfaces taking all degrees of freedom explicitly into account. These potentials are based on electronic structure calculations for representative configurations, which are then interpolated to a continuous energy surface that can be evaluated many orders of magnitude faster. We present a full-dimensional NN potential for the water dimer as a first step towards the construction of a NN potential for liquid water. This many-body potential is based on environment-dependent atomic energy contributions, and long-range electrostatic interactions are incorporated employing environment-dependent atomic charges. We show that the potential and derived properties like vibrational frequencies are in excellent agreement with the underlying reference density-functional theory calculations.
In recent years, the widely explored phenomenon “aggregation-induced emission (AIE)” has played a crucial role in the development of luminescent materials for light-emitting applications. In the same ...direction, the contribution of its sister concept “AIE switching” has been impressive. In comparison, the application of this concept in the field of biosensing or bioimaging is still in its infancy. Therefore, to shed light into the sensing of bioanalytes, we have developed a new perylenediimide (PDI)-based small fluorescent probe, benzoannulated PDI (Bp(Im)2MA), that selectively detects diamines and biogenic amines (BAs) in solution via an “AIE-switching” phenomenon. The synthesized probe containing the bay-annulated anhydride moiety exhibits strong cyan emission in solution. In the mechanism, we have shown that the terminal free amine group of BAs readily reacts with a highly reactive anhydride moiety, which opens the cyclic anhydride moiety. In the open conformation, the free amine group along with a carboxylate group modulates the polarity of the system strikingly. Because of this induced polarity, the monomer of Bp(Im)2MA-BAs conjugate aggregated in solution, thereby exhibiting a significant change in emission property in solution. This method may also be called a very simple and straightforward “naked eye” detection of BAs in solution, with a nanomolar detection limit. A detailed spectroscopic and microscopic investigation demonstrated the existence of the aggregated state. As the reporter dye also emits strongly in the solid state (yellowish orange), it therefore instantly made vapor-phase detection of BAs feasible. Finally, this vapor-phase detection of BAs by the probe was applied very effectively in the determination of spoilage of raw fish.
For mAbs to be viable therapeutics, they must be formulated to have low viscosity, be chemically stable, and have normal in vivo clearance rates. We explored these properties by observing ...correlations of up to 60 different antibodies of the IgG1 isotype. Unexpectedly, we observe significant correlations with simple physical properties obtainable from antibody sequences and by molecular dynamics simulations of individual antibody molecules. mAbs viscosities increase strongly with hydrophobicity and charge dipole distribution and decrease with net charge. Fast clearance correlates with high hydrophobicities of certain complementarity determining regions and with high positive or high negative net charge. Chemical degradation from tryptophan oxidation correlates with the average solvent exposure time of tryptophan residues. Aspartic acid isomerization rates can be predicted from solvent exposure and flexibility as determined by molecular dynamics simulations. These studies should aid in more rapid screening and selection of mAb candidates during early discovery.
Significance mAbs are increasingly being used for treatment of chronic diseases wherein the subcutaneous delivery route is preferred to enable self-administration and at-home use. To deliver high doses (several hundred milligrams) through a small volume (∼1 mL) into the subcutaneous space, mAb solutions need to have low viscosity. Concomitantly, acceptable chemical stability is required for adequate shelf life, and normal in vivo clearance is needed for less frequent dosing. We propose in silico tools that provide rapid assessment of atypical behavior of mAbs (high viscosity, chemical degradation, and fast plasma clearance), which are simply predicted from sequence and/or structure-derived parameters. Such analysis will greatly improve the probability of success to move mAb-based therapeutics efficiently into clinical development and ultimately benefit patients.
Direct time integration schemes are an integral part of the FEM simulation of structural dynamics problems. Such schemes should be at least second‐order accurate, unconditionally stable, and ...numerically dissipates the high‐frequency components. To this end, this article develops a time integration scheme, called modified v‐ST/FEM, which is based on the time‐discontinuous Galerkin method. The proposed method employs an unsymmetric triangular bubble function for relating the displacement field to the velocity field. The modified v‐ST/FEM contains two‐parameter α∈(0,0.5)$$ \alpha \in \left(0,0.5\right) $$ and β∈(−1,βc)$$ \beta \in \left(-1,{\beta}_c\right) $$ for controlling the dissipation of high‐frequency components. A comprehensive study of the influence of α$$ \alpha $$ and β$$ \beta $$ on the numerical performance of the proposed method is conducted. It is found that the error in the solution increases when the value of α$$ \alpha $$ increases. However, for all practical purposes, β$$ \beta $$ has a negligible influence on the accuracy of the proposed method. The modified v‐ST/FEM is second‐order accurate for α≠0.0$$ \alpha \ne 0.0 $$, and third‐order accurate for α=0.0$$ \alpha =0.0 $$. The numerical efficacy of the modified v‐ST/FEM is demonstrated by solving some benchmark problems and comparing its result to those obtained by other popular methods such as Trapezoidal rule, HHT‐α$$ \alpha $$, and Bathe's scheme.
After cardiovascular disease, cancer is the most common cause of death worldwide. Due to their versatility, heterocyclic compounds play an important role in drug discovery. Medical remedies are ...constantly being discovered, especially for catastrophic disorders such as cancer. Here, this review is focused on sulphur containing heterocyclic compounds as anticancer agents. Sulphur is found in a variety of vitamin cofactors, sugars, and nucleic acids, and it also plays a function in controlling translation by sulphurating transfer RNA. Sulphur has obtained a lot of interest in the anticancer research medicinal fields. Thiophene derivatives were tested for anti-proliferative activity against breast cancer cells in a recent screening study, and the bulk of chemicals exhibited potent inhibitory effects. In recent years, azoles such as thiazole and thiadiazole structures have gained prominence in cancer research.
Introduction of graphene into the stable matrix of Mn3O4-polyaniline composite leads to supercapacitor electrode that can deliver specific capacitance >1000 F g−1. This is nearly double the value, ...which is observed in conventional type Mn3O4-polyaniline composite that is able to deliver ~500 F g−1, at a scan rate of 5 mV s−1 in the voltage window −1 to 1 V. This value is also much greater than those obtained in most of the niche carbon or transition metal oxide based supercapacitors. Cycling studies, carried out at a current density 25 A g−1 and for 3000 cycles, indicated that the composite continue to retain nearly ~97% of the initial capacitance. The enhancement can be explained in terms of the connected percolated conductive path, which originates due to the dispersed graphene sheets.
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•Economical synthesis protocol for achieving a high performance composites is proposed.•The synthesized composite have 2 V (-1 V to +1 V) voltage window and deliver specific capacitance of ~1240 F g-1 at 2 A g-1.•The electrochemical response of the composite material is more than 3 times higher that individual components.
This paper aims to develop a moving-mesh type Finite Element Method for the computation of the transient unconfined seepage flow through the porous medium. The proposed method is based on the time ...discontinuous Galerkin Space-Time Finite Element Method (ST/FEM). It solves the seepage problem in the saturated region. The primary unknown in ST/FEM is piezometric pressure. Fluid velocities are derived from the pressure using Darcy's law. Further, an iterative algorithm has been proposed in this paper to implement the proposed method. In each iteration step, the computation domain is updated according to the flow velocity on the phreatic boundary. Subsequently, internal nodes are moved using the mesh moving technique to accommodate the newly updated computation domain. The mesh moving technique, which is discussed in this paper, is based on an elasticity problem. ST/FEM is employed to analyze several unconfined seepage flow problems, and results of steady state solutions are compared with those available in the literature to demonstrate the efficacy of the proposed scheme.
•Moving mesh type finite element method is developed for transient and unconfined seepage flow analysis.•The proposed scheme requires 2 to 3 iterations in a time step to achieve convergence.•Elasticity equation based automatic mesh moving technique is employed to move the internal nodes.•Initial computation domain significantly affects the deformation characteristics of mesh.•Proposed iterative scheme can be employed with any type of mesh moving technique.
Metastatic prostate cancer (mCaP) remains one of the leading causes of cancer-related death in men worldwide. Androgen receptor (AR) drives the progression of most of the mCaP, and hence the androgen ...deprivation therapy (ADT) is the first-line treatment of choice for mCaP. Although the responses of ADT and next-generation AR inhibitors initially improve the disease burden, the responses of this combinatorial drug therapy varied widely due to molecular alteration in mCaP patients. In addition to the altered AR signaling, loss of potent tumor-suppressor protein p53 exhibits poor outcomes. p53 influences cell plasticity and is frequently lost in more aggressive prostate cancer (CaP) with neuroendocrine differentiation. Loss of p53 antagonizes the effect of AR inhibitors and enhances the proliferation rate of CaP cells. Considering the important role of p53 inactivation in cancer development, restoration of wild-type p53 function by p53-reactivating compounds developed with different approaches, seems to be an attractive therapeutic strategy for prostate cancer therapy. In this review, we discuss the therapeutic potential of these compounds with a particular focus on the pharmacological rescue of p53 in mCaP. In addition, we also highlight the challenges and new opportunities of p53-targeted therapy for the future.
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