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Bacterial infection from medical devices is a significant problem and accounts for an increasing number of deaths and high medical costs. Surgical sutures are a major source of nosocomial infection through surgical wound contamination and the rates of which are increasing globally. One efficient way to prevent this is by modifying the surface of the sutures in such a way that no bacterial adhesion can occur. In this investigation, biodegradable polymer sutures with excellent antibacterial properties were developed. Antibacterial properties were achieved by coating nanosilver incorporated biopolymer polycaprolactone material on the surface of the sutures. Biocompatible polyethylene glycol was selected as the solvent for the dispersion of nanosilver particles, which improved the mechanical properties of the sutures. The nanoparticle coating was found to be uniform and more effective with the electrospinning method. The mechanical property of the coated suture was analysed using the Universal Test Method, and the results were in agreement with the standard results. The surface morphology of coated sutures becomes uniform on adding nanosilver particles, confirmed by scanning electron microscope studies. A comparative study of force–displacement, hardness, and reduced modulus as a function of contact depth indentation tests were performed on coated and uncoated suture samples using a Nanoindentation Test Machine. In-situ Scanning Probe Microscopy images were captured for coated and uncoated suture materials. These studies confirmed a new strategy in developing antibacterial sutures suitable for wound closure following surgery.

Increasing global demand for new, clean, nontoxic alternative energy resources has lead to a rapid swift in exploring new materials for the production of renewable energy. Thiophene based molecules attracted much attention for the fabrication of various organic electronic devices because of its excellent properties, synthetic flexibility and stability. In this context, we designed and synthesized dibenzothiophene based molecule namely 2,8-di-(4-formylphenyl)dibenzothiophene. Time-Dependent Density Functional Theory (TD-DFT) methods with PBEPBE functional using 6-311G++2d,2p basis set was used for theoretical calculations. The oligomer was synthesized by selective bromination followed by Suzuki coupling. The photophysical and electrochemical properties of this molecule were studied in detail and compared with the theoretical results.

Myristica fragrans Houtt., the source of very important spice 'nutmeg' used world over is native to India, Indonesia, Sri Lanka, South Africa and Southeast Asia. Phytochemical investigation of M. fragrans stem bark led to the isolation of bis-aryl dimethyl tetrahydrofuran lignans, such as grandisin [(7S,8S,7'S,8'S)-3,3',4,4',5,5'-hexamethoxy-7,7',8,8'-lignan] and (7S,8S,7'R,8'R)-3,3',4,4',5,5'-hexamethoxy-7,7',8,8'-lignan along with important lignans and neolignans, licarinA, licarin B, odoratisol A, (2S, 3R)-7-methoxy-3-methyl-5-((E)-prop-1-enyl)-2-(5-methoxy,3,4-methylenedioxyphenyl)-2,3-dihydrobenzofuran, elemicin, fragransin B1, raphidecursinol B, erythro-(7S,8R)-Δ8'-4,7-dihydroxy-3,5,3'-trimethoxy-8-O-4'-neolignan, erythro-(7S,8R)-Δ8'-7-hydroxy-3,4,3',5'-tetramethoxy-8-O-4'-neolignan, surinamensin.and β-sitosterol. Structures of the 12 compounds isolated were unambiguously identified by various spectroscopic methods. The former two compounds were isolated from M. fragrans for the first time. Furthermore, the X-ray crystal structure of odoratisol A is reported in this paper for the first time.

The nature of human resources and their willingness to contribute have an impact on the existence and growth of the organization. Employee loyalty may be defined as employees being committed to the success and growth of the organization and believing that working for this organization is their obligation and best option available to them. The growth and success of organizations in the present scenario, largely depends upon the commitment and loyalty of its workforce. As employees work for the organizations for certain period of time, they develop affinity and emotional attachment to the organization. As they grow older their maturity level will increase and stop job hopping. Further, as the age of the employee increases, they will try to settle down in one place and the probability of their intention to stay with the organization also will increase which in turn will influence their loyalty to the organization. Therefore, age of an employee is generally considered as a factor influencing loyalty to the organization.The purpose of this paper is to investigate the effect of age of employee on employees’ loyalty in a Bangalore based large scale public sector undertaking. 200 middle level executives who have completed minimum of one year service were surveyed and random sampling technique was adopted. Survey was conducted with a standardized, valid and reliable instrument measuring loyalty. The detailed findings and implications are discussed in the full paper.

The intrinsic catalytic properties of Montmorillonite K-10 clay have been utilized for Friedel–Crafts alkylation of the polycyclic caged enone 1 using different carbo and heterocyclic aromatic systems leading to novel compounds. Carbon–carbon bond formation between the aromatic compounds and the cage system has led to three different types of products.

The synthesis of the novel cage compounds 7-halomethyl-8-(carbomethoxy)tetracyclo[4.2.1.1 4,7 .0 2,5 ]deca-3-(11)-ene-10-ones, methyl-4-methylene-6-oxopentacyclo[5.4.0.0. 2,5 .0 3,10 .0 7,9 ]undecane-9-carboxylate, 3-chloromethyl-4-(carbomethoxy)tetracyclo[4.2.1.1. 3,8 .0 2,5 ]deca-7(11)ene-10-one, 2-bromo-5-methyl-8-methylene-6-oxotricyclo[5.3.0.0 3,9 ]decane-4-carboxylic acid and 2-bromo-5-methyl-8-methylene-6-oxotricyclo[5.3.0.0 3,9 ]decane-4-methyl carboxylate, achieved through base catalyzed rearrangement, is described.

Diels-Alder reaction of the cage compound 2 with itself, leading to the highly caged compound 3 , as well as with cyclopentadiene, leading to compounds 4 and 5 , is described.

Photochemical synthesis of the novel compounds 3-bromotetracyclo [5.3.1.02,6.04,8] undec-10(12)-ene-9,11-dione, 1-(bromomethyl)pentacyclo [5.4.0.02,6.03,10.05,9]undeca-8,11-dione and 1-bromo-9-(bromomethyl)pentacyclo [5.4.0.02,6.03,10.05,9]undeca-8,11-dione is described.

The global demand for wood as a building material is steadily growing, while the availability of this natural resource is diminishing. This situation has led to the development of alternative materials. Of the various synthetic materials that have been explored and advocated, polymer composites claim a major participation as building materials. There has been a growing interest in utilizing natural fibres as reinforcement in polymer composite for making low cost construction materials in recent years. Natural fibres are prospective reinforcing materials and their use until now has been more traditional than technical. They have long served many useful purposes but the application of the material technology for the utilization of natural fibres as reinforcement in polymer matrix took place in comparatively recent years. Economic and other related factors in many developing countries where natural fibres are abundant, demand that scientists and engineers apply appropriate technology to utilize these natural fibres as effectively and economically as possible to produce good quality fibre reinforced polymer composites for housing and other needs. Among the various natural fibres, sisal is of particular interest in that its composites have high impact strength besides having moderate tensile and flexural properties compared to other lignocellulosic fibres. The present paper surveys the research work published in the field of sisal fibre reinforced polymer composites with special reference to the structure and properties of sisal fibre, processing techniques, and the physical and mechanical properties of the composites. RESUMO O uso da madeira como material de construção continua crescendo mundialmente enquanto a disponibilidade deste recurso natural está diminuindo. Esta situação tem conduzido ao desenvolvimento de materiais alternativos. Dentre os vários materiais sintéticos que têm sido explorados, os compósitos poliméricos reivindicam e buscam uma maior participação como material de construção. Nos últimos anos tem se observado um crescente interesse na utilização de fibras naturais como reforço de matrizes poliméricas para a produção de materiais de baixo custo. As fibras naturais são reforços com grande potencialidade e seu uso tem se dado de forma mais tradicional do que científica. Elas têm se prestado a inúmeras aplicações ao longo do tempo, mas a aplicação da tecnologia dos materiais visando a sua utilização como reforço de matrizes poliméricas é relativamente recente. As dificuldades econômicos e sociais observadas em muitos dos países em desenvolvimento, onde as fibras naturais são abundantes, requerem que cientistas e engenheiros apliquem tecnologias apropriadas para utilizar estas fibras da forma mais eficiente possível, de tal maneira que se possa produzir materiais compósitos poliméricos de boa qualidade visando a atender a demanda da população por habitações e componentes habitacionais. Dentre as várias fibras naturais, a fibra de sisal é de particular interesse uma vez que os compósitos que a utilizam como reforço apresentam alta resistência ao impacto além de possuírem moderada resistência à tração e à flexão. O presente artigo apresenta uma revisão dos trabalhos de pesquisa publicados no campo dos compósitos poliméricos ecológicos, especialmente no que se refere aos compósitos reforçados com fibras de sisal, visando seu uso como material de construção. Ênfase especial é dada à micro-estrutura e propriedades da fibra de sisal, às técnicas de processamento e às propriedades físicas e mecânicas dos compósitos poliméricos reforçados com fibras de sisal.

The synthesis of novel polycyclic amides has been achieved through the reaction of bishalomethyl pentacyclo[5.4.0.02,6.03,10.05,9]undecane diones with acyclic and cyclic secondary amines in the presence of an ionic liquid. Three of the compounds prepared have been found to possess antituberculosis activity.