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Principals play a pivotal role in teachers’ professional growth, which impacts student outcomes. The purpose of this paper is to understand the perceptions principals have about effective elements of professional development (PD) and the role they play in facilitating the growth of teachers, and how this affects student learning.

Q methodology was utilized to investigate the subjective views of public school administrators about PD. A post sort survey was used to interpret demographic and perceptual data. The Q sorts were factor analyzed to reveal statistical correlations among the administrators. Focus group interviews representative of each emergent factor were then conducted with eight of the 34 principals who sorted the statements.

In total, 31 of the participants loaded on one of three factors. Though there were perceptional differences about which PD elements are effective, all of the principals expressed a desire to take an active role in teachers’ professional growth. These distinct viewpoints of PD included the themes of sustainability and collaboration.

School leaders are commonly named as the most important influence on teachers and their practices. PD is among the significant strategies that principals employ to impact teachers. Thus, studies that provide insights into how school leaders perceive PD are crucial to the in-service development of school teachers.

In this paper, the authors aim to examine and comparatively evaluate a recently-developed metaheuristic called crystal structure algorithm (CryStAl) – which is inspired by the symmetries in the internal structure of crystalline solids – in solving engineering mechanics and design problems.

A total number of 20 benchmark mathematical functions are employed as test functions to evaluate the overall performance of the proposed method in handling various functions. Moreover, different classical and modern metaheuristic algorithms are selected from the optimization literature for a comparative evaluation of the performance of the proposed approach. Furthermore, five well-known mechanical design examples are utilized to examine the capability of the proposed method in dealing with challenging optimization problems.

The results of this study indicated that, in most cases, CryStAl produced more accurate outputs when compared to the other metaheuristics examined as competitors.

This paper can provide motivation and justification for the application of CryStAl to solve more complex problems in engineering design and mechanics, as well as in other branches of engineering.

CryStAl is one of the newest metaheuristic algorithms, the mathematical details of which were recently introduced and published. This is the first time that this algorithm is applied to solving engineering mechanics and design problems.

This paper aims to synthesize new benzimidazole dyes aiming to study the solvent effects on their absorption in Ultraviolet-visible spectra.

Ureido/thioureido hydrazonamide benzimidazoles (U/THB) are prepared by condensation of N-aryl-1H-benzo[d]imidazole-2-carbohydrazonoyl bromides with ureido and/ or thioureido reagents. The target products are fully characterized for structural elucidation by means of their spectral and elemental methods. Solvatochromic behavior of U/THB dyes has been studied in different polar protic solvents at room temperature.

The absorption spectra distinguish two main bands at (350 nm–442 nm) and (308 nm–382 nm) referring to n-π* and π- π* transitions of the azo groups. Dimethyl formamide induces an extremely bathochromic transition comparing to the other protic solvents. The observed bathochromic shifts indicate strong interaction with solvents in the excited state. Most dyes show one absorbance in all solvents used, so they may exist in a single tautomeric form (hydrazo form).

In the present paper, the synthesis of U/THB dyes was achieved by a simple and convenient pathway. In addition, the variations in substituents attached to the chromophoric moiety could also be studied.

The new U/THB dyes are accountable for providing good knowledge about their solvation and spectral properties of an order acceptable for industrial utilization.

Synthesis of these new benzimidazole derivatives and study of their solvation and spectral properties provides good knowledge, which is very useful in many industrial applications (e.g. dye-sensitized solar cell, etc.).

The synthesized mono azo U/THB dyes are novel members in the benzimidazole family, where no details regarding the synthesis of such dyes are reported before in the literature. They are superior in terms of preparation, multiple applications and spectral properties.

This paper aims to synthesize a novel series of monoazo disperse dyes based on N-(1-phthalimidyl)-naphthalimides by coupling with substitute anilines, naphthylamines and naphthol derivatives.

The purification of the intermediates and the dyes was carried out by recrystallization. The structures of the synthesized intermediates and the dyes were elucidated by spectroscopic techniques. The absorption maxima, molar extinction coefficient and halochromic properties of the dyes were determined spectrophotometrically using solvents of different polarity.

The dyes were applied on polyester using a high-temperature high-pressure dyeing machine, and the dyeing performance parameters such as colour build-up on fabrics, wash fastness, perspiration fastness and light fastness were evaluated. The colour build-up was found to be very good and the wash fastness (4–5) and perspiration fastness (4–5) were excellent, whereas the light fastness was found to vary from moderate to very good (3–6).

It is not possible to investigate the structure of the synthesized dyes by nuclear magnetic resonance spectroscopic analysis due to the low solubility of dyes in deuterated solvents.

A novel method for the synthesis of a new category of monoazo disperse dyes based on N-(1-phthalimidyl)-naphthalimides was developed. These dyestuffs could be used in textile printing of polyester fabrics.

This study aims to prepare some disperse dyes based on pyrazole derivatives and fully evaluate their use as azo-disperse dyes linked with pyrazolo[1,5-a] pyrimidine. This study aims to prepare dye polyester fabric at different conditions (pH and time) at a depth of 4% using a high-temperature pressure process in water.

The disperse dyes were created by dissolving enaminone and pyrazole derivatives in glacial acetic acid and fusing sodium acetate at reflux for 6 h. The chemical structure of the produced dye was studied using elemental analysis, Fourier-transform infrared spectroscopy, 1H NMR and 13C NMR spectroscopic analytical methods. The dyeing of Dispersed dyes 14–16 on polyester under diverse conditions was comprehensively investigated in this work.

The prepared Organic dyes 14–16 were found to be highly functional and suitable for this type of dyeing technique. High color strength is possessed by the materials dyed with Disperse dyes 14–16. Even in low alkaline conditions, these dyes exhibited a strong affinity for polyester fabric, changing just little in response to pH changes. The hue of the dyed polyester samples varied from beige to reddish brown and yellowish brown because of the coupler moieties.

This study is important because it offers novel dyes that may be used to dye polyethylene terephthalate fibers that exhibit remarkable brightness and levelness. It also offers a viable solution for creating a variety of colors in polyester fabrics.

Recent reports on the state of management education are, typically, critical of the relevance of business school offerings to “real world” situations. Furthermore, they stress the need to internationalise the curriculum and develop personal and interpersonal skills through programmes which are more integrated and participative in design. This article discusses the pragmatic approach to international marketing education, which in seeking to address these issues, also recognises the broader role of universities in contributing to economic development.

This work aims to synthesize a series of novel acyclic and/or heterocyclic systems, as precursors for dyes with potential antimicrobial activity that could be used for simultaneous dyeing and antimicrobial textile finishing. Thus, a series of novel pyridine, thiophene and pyrazolo[3,4-b]pyridine derivatives were synthesized, and their antimicrobial and textile finishing properties were studied and evaluated.

The synthesis, structure elucidation and antimicrobial activities of the newly synthesized compounds based on 4,4-dicyano-3-phenyl-but-3-enoic acid phenylamide (1) were demonstrated. The minimal inhibitory concentration in μg/mL of the compounds showed significant antimicrobial activity against most of the tested organisms. On the other hand, their spectral characteristics and fastness properties were measured and evaluated. Antimicrobial activities of the dyed fabrics in terms of inhibition zones (mm) were measured and evaluated.

A series of novel heterocyclic compounds (Schemes 1-3) were synthesized based on starting material (1). Compounds (1), 2, 4a, 8a and 9c exhibited comparable or even higher antibacterial activities than the selected standards (ampicillin), while compounds 2, 3c, 3d, 4a and 8b revealed higher antifungal activities than the selected standard (cycloheximide). On the other hand, some dyes showed high antimicrobial evaluation on the dyed fabrics (nylon 66, acetate and polyester) expressed as size (mm) of inhibition zones (Tables I-IV).

Results revealed that many hydrazo and azo derivatives were synthesized from some pyridines and thiophenes. The antimicrobial evaluation and textile finishing of the newly synthesized products revealed significant and potent values of antimicrobial activity.

All the synthesized compounds were novel and most of them exhibited higher antimicrobial activities than the selected standards antibiotics, thus are valuable for simultaneous dyeing and antimicrobial functional finishing of textile fabrics.

The transformation of France under De Gaulle from the “sick man of Europe” with governments changing every few months, to one of the world's strongest economies, holds lessons for us all. Of course France's virtual self‐sufficiency in food and fuel always ensured an eventual resurgence under a strong and stable government. We thought of this recently on a trip to Western Provence, the oldest part of France and one off the beaten tourist track. It was one of the earliest provinces of Imperial Rome and in each settlement the Romans tried to reproduce a petite Rome, with arena, theatre, baths and villas, so that many Provencal towns have as many Roman antiquities as Rome itself. In its beauty of line and colour, its architecture, clustered villages on hilltops and the tall Lombardy pines, the countryside looks Italian, but the people seem unlike the Italian, Spanish or French. We thought them descendants of the ancient Gaul, whose tribes settled all over Western Europe, from the shores of the Mediterranean to Galway Bay.

A series of novel anchored mono‐ and disarylazo cationic pigments embodying long chain aliphatic amine moiety, as deflocculating unit, were prepared by amination of the newly synthesized heterocyclic Hansa Yellow analogue derivatives IVa‐g followed by reacting the products with p‐nitroso‐N,N‐dimethyl aniline. Synthesis and spectral behaviour of these products as well as their precursors were fully investigated. The hitherto prepared organic colourants showed preliminary improved bleeding and fastness properties.

This paper aimed to synthesise some new selenium-containing pyrazole, thiazole and thiophene dyestuffs and investigate their application in dyeing polyester fabrics.

4,4′-Diselanediyl-bis-(2-methoxyaniline) was diazotized by acetic acid/sodium nitrite and coupled with active methylene components such as malononitrile, ethyl cyanoacetate and ethyl acetoacetate, and their corresponding hydrazono products were cyclised with hydrazine or phenyl hydrazine to obtain a series of arylazo-pyrazole dyestuffs. Furthermore, diazo-coupling reactions of the diazotized 4,4′-diselanediyl-bis-(2-methoxyaniline) were developed to obtain a new series of 2-amino-5-arylazo-thiazole- and 4-aryazo-3-hydroxy-2-substituted thiophene dyestuffs.

The structure of the synthesised dyestuffs was established and confirmed based on their elemental analysis and spectral data (infrared, proton nuclear magnetic resonance and mass spectroscopies). The synthesised selenium-containing dyestuffs were applied as disperse dyes on polyester fabrics by high temperature-pressure technique. The dyeing characteristics of these dyestuffs were evaluated, and they were found to exhibit good fastness properties.

A series of symmetrical diselenide dyestuffs containing pyrazole, thiazole or thiophene coupler components were synthesised. The authors studied their application for dyeing polyester fabrics; they are superior in terms of preparation, yield, purity and fastness properties.