Sequential Synthesis Methodology Yielding Well-Defined Porous 75%SrTiO3/25%NiFe2O4 Nanocomposite

In this research, we reported on the formation of highly porous foam SrTiO3/NiFe2O4 (100−xSTO/xNFO) heterostructure by joint solid-state and sol-gel auto-combustion techniques. The colloidal assembly process is discussed based on the weight ratio x (x = 0, 25, 50, 75, and 100 wt %) of NiFe2O4 in the 100−xSTO/xNFO system. We proposed a mechanism describing the highly porous framework formation involving the self-assembly of SrTiO3 due to the gelation process of the nickel ferrite. We used a series of spectrophotometric techniques, including powder X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), N2 adsorption isotherms method, UV-visible diffuse reflectance spectra (UV-Vis DRS), vibrating sample magnetometer (VSM), and dielectric measurements, to investigate the structural, morphological, optical, magnetic, and dielectric properties of the synthesized samples. As revealed by FE-SEM analysis and textural characteristics, SrTiO3-NiFe2O4 nanocomposite self-assembled into a porous foam with an internally well-defined porous structure. HRTEM characterization certifies the distinctive crystalline phases obtained and reveals that SrTiO3 and NiFe2O4 nanoparticles were closely connected. The specific magnetization, coercivity, and permittivity values are higher in the 75STO/25NFO heterostructure and do not decrease proportionally to the amount of non-magnetic SrTiO3 present in the composition of samples.

Status and Challenges on Design and Implementation of Camber Morphing Mechanisms

This paper presents state-of-the-art technologies of camber morphing mechanisms from the perspectives of design and implementation. Wing morphing technologies are aimed at making the aircraft more energy or aerodynamically efficient during flight by actively adjusting the wing shape, but their mechanism designs and implementation aspects are often overlooked from practical sense in many technical articles. Thus, it is of our interest that we thoroughly investigate morphing mechanisms and their nature of design principles and methodologies from the implementation and test flight aspects, navigate the trends, and evaluate progress for researchers’ methodology selection that possibly turns to design and build stages. This paper categorizes the camber morphing mechanisms from a wide collection of literature on morphing wings and their mechanisms, and the defined classifications are based on mechanism’s design features and synthesis methodology, i.e., by the tools and methods used to solve the design problem. The categories are (1) structure-based, (2) material-based, and (3) hybrid. Most of the structure-based camber morphing mechanisms have distinctive structural features; however, the material-based camber morphing mechanisms make use of material properties and tools to enhance the elastic nature of its structures. Lastly, the hybrid morphing mechanisms are a combination of both the aforementioned categories. In summary, this review provides researchers in the field of morphing mechanisms and wings with choices of materials, actuators, internal and external structure design for wings, and overarching process and design methodologies for implementation with futuristic and practical aspects of flight performance and applications. Moreover, through this critical review of morphing mechanism, selective design criteria for appropriate morphing mechanisms are discussed.

Assimilation, Integration or Inclusion? A Dialectical Perspective on the Organizational Socialization of Migrants

Given the increasing importance of migrations around the world, and the challenges that migrants face in entering the labor market, the process of socialization of migrants into organizations deserves more attention from management scholars. Indeed, societal discourses promoting equality and diversity often appear to be in contradiction with the unequal power relations migrants experience on entering the workforce. Drawing on a dialectic perspective and a qualitative meta-synthesis methodology, we show how the practices engaged in by organizations to socialize migrant employees are deeply embedded in and influenced by macro-social contexts that may place migrants at a disadvantage, giving rise to emerging tensions. We examine a range of contingencies that can mitigate the inequalities that migrants experience, and we reveal a variety of dynamic dialectical pathways surrounding migrant socialization practices through which they may be reproduced or transformed depending on the mutual relationships between situated conditions, emerging tensions and human praxes.

Synthesis of small molecule inhibitors for the treatment of disease

<p>Three aspects of the protecting-group-free (PGF) synthesis of small molecules have been described in this thesis. In the first part, the PGF azasugar synthesis methodology was applied to 2-deoxy-D-glucose with the intention of selectively forming the six-membered azasugar 5-epi-fagomine. Surprisingly, four products were formed in the key I2-mediated carbamate annulation step, with a pyrrolidine being the major product after optimisation. This was formed in 15% yield. A mechanism that explains the formation of the four carbamates was proposed, which was supported by an investigation into related halocyclisation reactions. The next part of this thesis describes the development of a new PGF methodology for the synthesis of conduramines, another class of biologically interesting molecules. Conduramines are amino polyhydroxy cyclohexenes and some conduramines have glycosidase inhibitory activity. These molecules are also useful precursors to a variety of biologically useful molecules including aminocyclitols and azasugars. The key steps in the PGF synthesis of conduramines are a Vasella-Barbier amination, a reaction that forms new C-C and C-N bonds concomitantly, and a ring closing metathesis in the presence of free hydroxyl and amine groups. To this end, a 4-deoxy 3-conduramine was prepared in just four steps and in 27% yield. Finally, the preparation of an amine library and its biological testing for the identification of a new anti-tuberculosis drug is described. Two short syntheses were used to prepare alkenylamines and amines from the corresponding sugar, with various lipophilic groups attached to the amine. A 20-member amine library was prepared, and the compounds were tested for anti-mycobacterial activity in a mycobacterial growth inhibition assay. The most active compounds were subjected to further biological testing to determine their general cytotoxic properties. Two amines, arabinohexadecylamine and arabinohexadecylmethylamine, were identified as having the best potential for use as anti-tuberculosis drugs, and have been sent to Colorado State University for subsequent in vivo testing in a mouse model of tuberculosis.</p>

Synthesis of small molecule inhibitors for the treatment of disease

<p>Three aspects of the protecting-group-free (PGF) synthesis of small molecules have been described in this thesis. In the first part, the PGF azasugar synthesis methodology was applied to 2-deoxy-D-glucose with the intention of selectively forming the six-membered azasugar 5-epi-fagomine. Surprisingly, four products were formed in the key I2-mediated carbamate annulation step, with a pyrrolidine being the major product after optimisation. This was formed in 15% yield. A mechanism that explains the formation of the four carbamates was proposed, which was supported by an investigation into related halocyclisation reactions. The next part of this thesis describes the development of a new PGF methodology for the synthesis of conduramines, another class of biologically interesting molecules. Conduramines are amino polyhydroxy cyclohexenes and some conduramines have glycosidase inhibitory activity. These molecules are also useful precursors to a variety of biologically useful molecules including aminocyclitols and azasugars. The key steps in the PGF synthesis of conduramines are a Vasella-Barbier amination, a reaction that forms new C-C and C-N bonds concomitantly, and a ring closing metathesis in the presence of free hydroxyl and amine groups. To this end, a 4-deoxy 3-conduramine was prepared in just four steps and in 27% yield. Finally, the preparation of an amine library and its biological testing for the identification of a new anti-tuberculosis drug is described. Two short syntheses were used to prepare alkenylamines and amines from the corresponding sugar, with various lipophilic groups attached to the amine. A 20-member amine library was prepared, and the compounds were tested for anti-mycobacterial activity in a mycobacterial growth inhibition assay. The most active compounds were subjected to further biological testing to determine their general cytotoxic properties. Two amines, arabinohexadecylamine and arabinohexadecylmethylamine, were identified as having the best potential for use as anti-tuberculosis drugs, and have been sent to Colorado State University for subsequent in vivo testing in a mouse model of tuberculosis.</p>

Disciplinary differences in the study of the relationship between social variables and mental health: A systematic mapping review

There has been sustained interest in the intersection between social constructs and mental health from diverse disciplines including psychiatry, sociology and public health. However, no systematic attempt has been made to catalogue what is meant by ‘social’ by different researchers, how variables deemed ‘social’ constructs are linked to mental health, nor whether these patterns differ by academic discipline. Understanding interdisciplinary differences and commonalities may reveal opportunities for interdisciplinary collaboration to enhance our understanding of how social factors relate to mental health. This article presents a prospectively registered systematic map of social approaches to mental health using an innovative synthesis methodology (coding all sentences from a random selection of N = 287 articles). Results indicated that although approaches are diverse, disciplinary overlap is substantial. Psychology and psychiatry led articles tend to focus on social skills or emotions as features of mental (ill-)health, while public health and social sciences led articles tend to focus on social relationships, status or context as determinants of mental (ill-)health. Medicine led articles were most likely to focus on social outcomes of mental (ill-)health. Potential growth areas are noted, particularly the relative dearth of intervention research drawing upon social approaches. The findings are discussed with a view towards enabling more effective interdisciplinary collaboration.

The Improvement of Picric Acid Synthesis Methodology

Explosives have the greatest importance in human practical activities, not only at time of war, but at tranquility as well. Nowadays, huge amount different type of explosives is synthesized, and fabricated for military and civilian applications. Nevertheless, this fact doesn’t exclude necessity of synthesis of new explosives for optimization of their characteristics, such as prime cost, power, safety during production, storage, transfer and etc. Picric acid is a fairly strong and energetic explosive, at the same time, beside to its explosive properties, it is characterized with antibacterial nature and it is the best yellow dye, especially for dyeing animal and plant tissues. The synthesis of picric acid structural analogues, is the main purpose of the research. One of the reasons of synthesis picric acid and further preparation of its structural analogues is safe nature of substances of this group, which makes them safe to various manipulations. On the other hand, it is well known that the synthesis and production of explosives is classified as high risk and costly technology. Therefore, even a small increase of their production productivity, is interesting from the economic effect point of view. During an investigation, changing of reaction conditions (temperature, concentrations and dosage of reagents) the improved method for syntheses of picric acid was developed. As result the significant increase of practical yield of picric acid, from 46% to 86% was achieved. Synthesized picric acid was placed in steel tube and tested on initiation of detonation in explosive camera. The description of modified method, comparisons to conventional technology, as well as explosion testing results is described in the paper.

A Survey of the Combinatorial Paraphernalia in Protein Synthesis

Statement of the Problem: The combinatorial paraphernalia in protein synthesis to be surveyed are multifarious, embracing, phenomena, processes, activities and materials, all characterized by plurality and dissimilarity. The materials usable are phenomenal and must be a set of discrete plural and dissimilar objects, e.g. the RNA four bases of Adenine, Uracil, Guanine, Cytosine (A,U,G,C) for the activity of permutation for building genetic code. Sequences for protein type sequence composition, proliferation and diversification as inherent in protein synthesis. Methodology and Theoretical Orientation: We are in for combinatorics which is the scientific study of the phenomenon of input/output productivity exhibited by a duality of numeral entities as in permutation of specified set (n) of dissimilar discrete plural. Things and selection (r) of them. The Dalina apparatus of Input/Output Multiplicative Replication system equipped with Square Kinematics View Mixing Technique sourced from inchoate Numeration Science literature being developed by this author is in use for the computation of 4 from 4 permutations of RNA four bases, A,U,G,C constituting the 24 quadruplet genetic code as the workforce in protein synthesis. Findings: The combinatorial paraphernalia in protein synthesis identified and surveyed comprise 14 characteristics, 3 materials and 11 processes/operatives. Conclusion and Significance: The relevance of the several identified and surveyed combinatorial paraphernalia in protein synthesis has been demonstrated by the test of agreeability with the working of the Dalina apparatus of Input/ Output Multiplicative Replication Combinatorial System using the Square Kinematics View Mixing technique for the computation of permutations of RNA four bases A,U,G,C making up the 24 quadruplet genetic code as the workforce in protein synthesis for the substance of all plants and animals throughout CREATION.