Size Reduction and Harmonics Suppression in Microwave Power Dividers: A Comprehensive Review

In this paper, several types of microstrip power divider are studied and compared in terms of harmonics suppression and size reductions. The importance of this research lies in the fact that power dividers are critical components in various communication systems, and their performance directly affects the overall system efficiency. The conventional structure of the power divider has an acceptable performance at operating frequency in terms of excellent output ports isolation, low insertion loss, and high return loss, but occupies large size and passes unwanted signals at higher frequencies along with desired signal without any suppression. Harmonics are popular distortion and has different distortion impacts in many different facilities. Recently, several techniques are introduced to overcome these drawbacks. Applied open stubs, applied resonators, lumped reactive components such as capacitors and inductors, coupled lines, defected ground structure (DGS), and electronic band gaps are common methods, which are widely used to overcome these drawbacks. Finally, the study results show that the resonator-based power dividers and coupled-line-based power dividers have good performances in terms of size reduction and harmonic suppression but increase insertion loss parameter. Furthermore, the lumped reactive component-based power dividers and applied DGS and electromagnetic bandgap cells suppress unwanted harmonics, but they need extra process to fabrication, which is undesirable. Moreover, the open-stub-based power dividers have moderate performance with simple structure, but size reduction and harmonics suppression are not so superior in this method

Multiple Authorities Access under Public Cloud Storage

Public cloud storage is a cloud storage model that provide services to individuals and organizations to store, edit and manage data. Public cloud storage service is also known as storage service, utility storage and online storage. Cloud storage has many advantages, there is still remain various challenges among which privacy and security of users data have major issues in public cloud storage. Attribute Based Encryption(ABE) is a cryptographic technique which provides data owner direct control over their data in public cloud storage. In the traditional ABE scheme involve single authority to maintain attribute set which can bring a single-point bottleneck on both security and performance. Now we use threshold multi-authority Cipher text-Policy Attribute-Based Encryption (CP-ABE) access control scheme, name TMACS. TMACS is Threshold Multi-Authority Access Control System. In TMACS,multiple authority jointly manages the whole attribute set but no one has full control of any specific attribute. By combining threshold secret sharing (t,n) and multi-authority CP-ABE scheme, we developed efficient multi-authority access control system in public cloud storage

Multiple Authorities Access under Public Cloud Storage

Public cloud storage is a cloud storage model that provide services to individuals and organizations to store, edit and manage data. Public cloud storage service is also known as storage service, utility storage and online storage. Cloud storage has many advantages, there is still remain various challenges among which privacy and security of users data have major problem in public cloud storage. Attribute Based Encryption(ABE) is a cryptographic technique which provides data owner direct control over their data in public cloud storage. In the traditional ABE scheme involve only single authority to maintain attribute set which can bring a single-point bottleneck on both security and performance. Now we use threshold multi-authority Cipher Text-Policy Attribute-Based Encryption (CP-ABE) access control scheme, name TMACS. TMACS is Threshold Multi-Authority Access Control System. In TMACS,multiple authority jointly manages the whole attribute set but no one has full control of any specific attribute. By combining threshold secret sharing (t,n) and multi-authority CP-ABE scheme, we developed efficient multi-authority access control system in public cloud storage

A brief review on bilayer floating tablet

Bilayer tablet is innovative period for the successful improvement of controlled release formulation along with a variety of features to provide a technique of successful drug delivery system. Controlled release dosage forms have been comprehensively used to improve therapy with several important drugs. Inclusion of drug in controlled release gastro-retentive dosage forms which can remain in the gastric region for several hours would considerably extend the gastric residence time of drugs and improve bioavailability, reduce drug waste and enhance the solubility of drugs that are less soluble in high pH environment. Numerous approaches are presently utilized in the prolongation of Gastric Retention Time, including floating drug delivery system, swelling and expanding systems, polymeric bio adhesive systems, high-density systems, modified shape systems and other deferred gastric emptying strategy

Polymeric micelle as a nanocarrier for delivery of therapeutic agents: A comprehensive review

For selective and effective drug delivery of therapeutic agent nanocarriers are the most effective agents. Micelles are an aggregate of surfactant molecules that dispersed in a liquid colloid. Micelles have a variety of shapes such as spheres, rods, vesicles, tubules, and lamellae. The shape and size of a micelle are a function of the molecular geometry of its surfactant molecules and solution conditions such as surfactant concentration, temperature, pH, and ionic strength. Poly Ethylene Glycol (PEG) is the most commonly used hydrophilic segment of micelles for drug delivery. Besides PEG, other polymers including poly (N-vinyl pyrrolidone) (PVP) and poly (N-isopropyl acrylamide) (pNIPAM) have also been used as hydrophilic portion of micelles. In this review we all discus about the polymeric micelles (PMs) as a nanocarriers for delivery of therapeutic agents. Keywords: Polymeric Micelles, Colloids, Nanocarriers, Drug Delivery, Poly Ethylene Glycol(PEG

Static- and dynamical-phase transition in multidimensional voting models on continua

A voting model (or a generalization of the Glauber model at zero temperature) on a multidimensional lattice is defined as a system composed of a lattice each site of which is either empty or occupied by a single particle. The reactions of the system are such that two adjacent sites, one empty the other occupied, may evolve to a state where both of these sites are either empty or occupied. The continuum version of this model in a Ddimensional region with boundary is studied, and two general behaviors of such systems are investigated. The stationary behavior of the system, and the dominant way of the relaxation of the system toward its stationary state. Based on the first behavior, the static phase transition (discontinuous changes in the stationary profiles of the system) is studied. Based on the second behavior, the dynamical phase transition (discontinuous changes in the relaxation-times of the system) is studied. It is shown that the static phase transition is induced by the bulk reactions only, while the dynamical phase transition is a result of both bulk reactions and boundary conditions.Comment: 10 pages, LaTeX2

Resealed Erythrocyte: an Approach to Targeted Drug Delivery

Application of erythrocytes, the most abundant cells of the human body with desirable physiologic and morphologic characteristics, in drug delivery has been exploited extensively. Among the various carriers used for targeting drugs to various body tissues, the cellular carriers meet several criteria desirable in clinical applications, among the most important being biocompatibility of carrier and its degradation products. Leucocytes, platelets, erythrocytes, nanoerythrocytes, hepatocytes, and fibroblasts etc. have been proposed as cellular carrier systems. Among these, the erythrocytes have been the most investigated and have found to possess greater potential in drug delivery. Biopharmaceuticals, therapeutically significant peptides and proteins, nucleic acid-based biological, antigens, anticancer drug and vaccines, are among the recently focused pharmaceuticals for being delivered using carrier erythrocytes. Erythrocytes, also known as red blood cells, and have been extensively studied for their potential carrier capabilities for the delivery of drugs. The biocompatibility, non-pathogenicity, non-immunogenicity and biodegradability make them unique and useful carriers

Exactly solvable models through the empty interval method

The most general one dimensional reaction-diffusion model with nearest-neighbor interactions, which is exactly-solvable through the empty interval method, has been introduced. Assuming translationally-invariant initial conditions, the probability that $n$ consecutive sites are empty ($E_n$), has been exactly obtained. In the thermodynamic limit, the large-time behavior of the system has also been investigated. Releasing the translational invariance of the initial conditions, the evolution equation for the probability that $n$ consecutive sites, starting from the site $k$, are empty ($E_{k,n}$) is obtained. In the thermodynamic limit, the large time behavior of the system is also considered. Finally, the continuum limit of the model is considered, and the empty-interval probability function is obtained.Comment: 12 pages, LaTeX2

Investigating the relationship between low serum cholesterol and suicide in attempters with depression

Background & Objective: It has been postulated that depressed individuals with low total cholesterol levels may be more likely to die prematurely from suicide. This study aimed to examine the association between low serum cholesterol and suicide in depressed attempters. Materials & Methods: In this cross-sectional study, 180 suicide attempters, who met the inclusion criteria and were willing to participate in the study, were recruited in 2017. The data was collected using a demographic questionnaire and the Beck Depression Inventory-Second Edition (BDI-II). The blood cholesterol level was measured via an auto-analyzer. Results: The mean age was 26.39±10.75 years. The average cholesterol level in the moderate, severe, and serious depression groups was 151.30±35.23, 145.89±36.32, and 145.15±33.33, respectively. The mean age was higher in the group with a higher depression level, though the difference was not significant (P=0.06). The percentage of suicide attempts in single individuals was significantly higher (P=0.02). The mean cholesterol level in the group with the highest level of depression was the lowest, but the difference was insignificant (r=-.01, P=0.85). Only in females, the level of blood cholesterol showed a nearly significant difference between groups with different severities of depression (P=0.05). Cholesterol had a significant correlation with suicide frequency (P=0.008, r=0.28). Conclusion: Our results revealed no significant association between low serum cholesterol and suicide in attempters with depression; but low total serum cholesterol may be associated with depression and suicide in depressed subjects. Yet, more studies are required for verification of this causality. © 2020, Journal of Advances in Medical and Biomedical Research. All rights reserved