Synthesis and Biological Evaluation of Imidazo[2,1‐b][1,3,4]thiadiazole‐Linked Oxindoles as Potent Tubulin Polymerization Inhibitors

A series of imidazo[2,1‐b][1,3,4]thiadiazole‐linked oxindoles composed of an A, B, C and D ring system were synthesized and investigated for anti‐proliferative activity in various human cancer cell lines; test compounds were variously substituted at rings C and D. Among them, compounds 7 ((E)‐5‐fluoro‐3‐((6‐p‐tolyl‐2‐(3,4,5‐trimethoxyphenyl)‐imidazo[2,1‐b][1,3,4]thiadiazol‐5‐yl)methylene)indolin‐2‐one), 11 ((E)‐3‐((6‐p‐tolyl‐2‐(3,4,5‐trimethoxyphenyl)imidazo[2,1‐b][1,3,4]thiadiazol‐5‐yl)methylene)indolin‐2‐one), and 15 ((E)‐6‐chloro‐3‐((6‐phenyl‐2‐(3,4,5‐trimethoxyphenyl)imidazo[2,1‐b][1,3,4]thiadiazol‐5‐yl)methylene)indolin‐2‐one) exhibited potent anti‐proliferative activity. Treatment with these three compounds resulted in accumulation of cells in G₂/M phase, inhibition of tubulin assembly, and increased cyclin‐B1 protein levels. Compound 7 displayed potent cytotoxicity, with an IC₅₀ range of 1.1–1.6 μM , and inhibited tubulin polymerization with an IC₅₀ value (0.15 μM ) lower than that of combretastatin A‐4 (1.16 μM ). Docking studies reveal that compounds 7 and 11 bind with αAsn101, βThr179, and βCys241 in the colchicine binding site of tubulin.     

Investigation of Tool Wear and Surface Finish by Analyzing Vibration Signals in Turning Assab-705 Steel

Various occurrences in machining influence the machining dynamics and thus produce vibration in the cutting tool-workpiece arrangement. In this investigation, with tri-axial accelerometer mounted on the tool-holder in turning ASSAB-705 steel, vibration signals have been captured with and without cutting. The nature of vibrations arising in the cutting tool at different cutting conditions has been investigated. It has been observed that the RMS amplitude of vibration along all three axes for the increasing cutting speed was mixed in nature; however, an increasing trend was noticed in the vibrations along the feed, V_x and radial, V_y directions. The vibration along the main cutting direction, V_z was mixed, initiated by large vibration and then decreased until a particular cutting speed was reached and finally increased steadily. The feed vibration component, V_x has a similar response to the change of the workpiece surface roughness, while the other two components, V_y and V_z have the more coherent response to the rate of flank wear progression throughout the tool life. The natural frequency of different machine parts vibration has been found to be within the band of 0 Hz – 4.2 kHz, whereas the frequencies of different occurrences in turning varied between 98 Hz and 42 kHz.     

Experimental and theoretical analysis of friction stir welding of Al–Cu joints

This paper presents a study of friction stir welding of aluminium and copper using experimental work and theoretical modelling. The 5083-H116 aluminium alloy and pure copper were successfully friction-stir-welded by offsetting the pin to the aluminium side and controlling the FSW parameters. A theoretical analysis is presented along with key findings. The process temperatures are predicted analytically using the inverse heat transfer method and correlated with experimental measurements. The temperature distribution in the immediate surroundings of the weld zone is investigated together with the microstructures and mechanical properties of the joint. This was supported by a finite element analysis using COMSOL Multiphysics. In this study, two rotational speeds were used and a range of offsets was applied to the pin. The microstructure analysis of the joints was undertaken. This revealed some particles of Cu inclusion in the nugget zone. The energy dispersive spectroscopy showed a higher diffusion rate of aluminium towards the interface while copper maintained a straight base line.     

Development of questionnaire to assess manufacturing capability along different decision areas

Superior manufacturing capability provides long lasting competitive benefits to a company in the market. It is thus imperative to have an instrument to assess the manufacturing capability of companies. However, empirically tested and reliable tools for the purpose of evaluation of manufacturing capability along different decision areas are scarcely available in the literature. This paper develops questionnaires based on generally accepted principle of instrument design to assess the manufacturing capabilities along different decision areas for four categorization schemes of manufacturing decision areas reported in the literature. The reliability and validity of all four instruments are assessed through responses from managers of 32 manufacturing units and are found to be satisfactory for most of the factors. The criterion validity is found to be fairly good for all the four instruments.     

Design,Fabrication and Experimentation of a Deep Drawing Machine

This paper presents the work implemented in designing, fabricating and operating a model of a cheap hydraulic DDM （deep drawing machine）, which is currently utilized in the manufacturing processes lab in the IED （Industrial Engineering Department） at An-Najah National University. The machine is used to conduct different experiments related to the deep drawing process. This work was implemented in three stages： the first was the design stage, in which all design calculations of the DDM elements were completed based on the specifications of the product （cup） to be drawn; the second was the construction stage, in which the DDM elements were fabricated and assembled at the engineering workshops of the university; the last was the operating and experimentation stage, in which the DDM was tested by conducting different experiments. The experience gained from designing and constructing such a mechanical lab equipment was found to be successful in terms of obtaining practical results that agree with those available in literature, cost-effective relative to the cost of a similar purchased equipment, as well as enhancing students＇ abilities in understanding the deep drawing process in particular and machine elements design concepts in general.     

Reserves Accumulated in Non-Photosynthetic Organs during the Previous Growing Season Drive Plant Defenses and Growth in Aspen in the Subsequent Growing Season

Plants store non-structural carbohydrates (NSC), nitrogen (N), as well as other macro and micronutrients, in their stems and roots; the role of these stored reserves in plant growth and defense under herbivory pressure is poorly understood, particularly in trees. Trembling aspen (Populus tremuloides) seedlings with different NSC and N reserves accumulated during the previous growing season were generated in the greenhouse. Based on NSC and N contents, seedlings were assigned to one of three reserve statuses: Low N–Low NSC, High N–Medium NSC, or High N–High NSC. In the subsequent growing season, half of the seedlings in each reserve status was subjected to defoliation by forest tent caterpillar (Malacosoma disstria) while the other half was left untreated. Following defoliation, the effect of reserves was measured on foliar chemistry (N, NSC) and caterpillar performance (larval development). Due to their importance in herbivore feeding, we also quantified concentrations of phenolic glycoside compounds in foliage. Seedlings in Low N-Low NSC reserve status contained higher amounts of induced phenolic glycosides, grew little, and supported fewer caterpillars. In contrast, aspen seedlings in High N-Medium or High NSC reserve statuses contained lower amounts of induced phenolic glycosides, grew faster, and some of the caterpillars which fed on these seedlings developed up to their fourth instar. Furthermore, multiple regression analysis indicated that foliar phenolic glycoside concentration was related to reserve chemistry (NSC, N). Overall, these results demonstrate that reserves accumulated during the previous growing season can influence tree defense and growth in the subsequent growing season. Additionally, our study concluded that the NSC/N ratio of reserves in the previous growing season represents a better measure of resources available for use in defense and growth than the foliar NSC/N ratios.     

Small/medium nuclear reactors for potential desalination applications : Mini review

Small/medium nuclear reactors (SMRs) are a promising alternative for powering large scale desalination plants. The modern generations of these systems manifest cost effectiveness and built-in safety features. The compatibility with geological and topological challenges is an added advantage. Moreover, funding opportunities and packages could be easily arranged for small/medium nuclear reactors (SMR). This mini review article provides the latest technical features of SMR nuclear plants with emphasis on pressurized light water reactors (PWR), boiling water reactors (BWR), heavy water reactors (HWR), gas cooled reactors (GCR), and liquid metal fast breeder reactors (LMFBR). Preliminary cost indicators for typical units were investigated as a part of joint effort to develop a cost database for these types of reactors. Security and safety features of small/medium reactors are identified and reviewed. This paper identifies and briefly discusses the various types of small/medium nuclear reactors to provide a preliminary evaluation and consideration of using this type of reactor in potential seawater desalination applications.     

Effects of gating design on structural and mechanical properties of high manganese steel by optimizing casting process parameters

Journal of Mechanical Science and Technology - The impacts of gating design and riser system on structure-property relationship of high manganese steel specimens produced by CO2 sand molding...