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This communication reports on the utility of a triazine-based self-assembling system, reminiscent of a Janus G–C nucleobase, as a building block for developing (1) supramolecular polymers, (2) peptide nucleic acids (PNAs), and (3) smart polymers. The strategically positioned self-complementary triple H-bonding arrays DDA and AAD facilitate efficient self-assembly, leading to a linear supramolecular polymer.

The tourism supply chain literature has predominantly focused on price-sensitive demand and ignored the service-sensitive demand issue. In competitive practice, both price- and service-sensitive demand play a significant role for tourists in selecting a tour package. In this paper, the authors discuss a case in which two tour operators compete on price and service to offer tour packages and serve the customers through a common local operator. The authors develop a mathematical model for a tourism supply chain under three scenarios: (i) a decentralized scenario, (ii) an integrated-channel scenario, and (iii) a global scenario. The results show that the tourism supply chain generates more profit when there is competition compared with when there is no competition. Furthermore, the results show that coordination among supply chain members with surplus sharing contracts improves the overall tourism supply chain profit compared with the decentralized scenario.

The essential oil of Hedychium spicatumrhizome is used in perfumery and medicines. The rhizome is reported to be stomachic, carminative, a bronchodilator stimulant and a tonic. For studying seasonal variation of the composition of its volatiles, rhizomes of H. spicatumwere collected from the Council of Scientific and Industrial Research–Institute of Himalayan Bioresource Technology (CSIR-IHBT), Palampur, Himachal Pradesh, India. To study the spatial diversity in essential oil content and composition, the rhizomes were collected from five different locations of Himachal Pradesh. Essential oils obtained by hydro-distillation were evaluated for their chemical composition by gas chromatography (GC) and GC/mass spectrometry (GC/MS) analyses. Twenty-two compounds were identified from the rhizome oil with major components 1,8-cineole, β-eudesmol, β-pinene and 10-epi–γ-eudesmol. All the essential oil samples were evaluated for their antioxidant activity by 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging activity. The essential oil extracted from the rhizomes collected from Biling had highest antioxidant activity; hence, it was also tested for cytotoxic activity against C-6, A549 and SiHa cell lines.

Supplier performance evaluation in buyer-supplier relationships from the buyer perspective is an important research issue among researchers and practitioners. Many studies have been conducted to measure the buyer’s satisfaction with the supplier’s performance in buyer-supplier relationships. However, very few studies present in the literature that deal with measurement of suppliers’ satisfaction in buyer-supplier relationships. The purpose of this study is to identify the factors that affect the suppliers’ satisfaction in buyer-supplier relationships and explore their relationships with suppliers’ satisfaction. A questionnaire survey was conducted among 300 suppliers organisation. Based on the influencing factors, four hypotheses were developed and tested in the framework of structural equation modelling.

Introduction: The potential therapeutic applications of thyrotropin-releasing hormone (TRH) have attracted attention, based on its broad-spectrum neuropharmacological action rather than its endocrine properties. These central nervous system (CNS)-mediated effects provide the rationale for use of TRH and its analogs in the treatment of brain and spinal injury, and CNS disorders like schizophrenia, Alzheimer's disease, epilepsy, amyotrophic lateral sclerosis, Parkinson's disease, depression, shock and ischemia.Areas covered: This review summarizes the patent literature and advances in the discovery and development of novel TRH analogs over the past 20 years. It provides a comprehensive overview of the development of new TRH analogs, giving emphasis to their pharmaceutical profile.Expert opinion: The use of TRH in the treatment of various CNS disorders has been proven clinically. However, TRH itself is a poor drug candidate due to its short plasma half-life (5 min), poor biopharmaceutical properties (low intestinal and CNS permeability) and endocrine side effect. Nevertheless, researchers have come up with metabolically stable, more potent and selective TRH analogs and prodrugs. Taltirelin, one of the TRH analogs, has been approved under the trade name of Ceredist®in Japan for the treatment of spinocerebellar degeneration. Several other TRH analogs are in various stages of preclinical or clinical development.

Brinjal (Solanum melongenaL.) is an important Solanaceae vegetable. It is a good source of minerals and vitamins and has medicinal properties. India, being a primary center of origin, possesses large variability for growth habit; leaf blade lobing; calyx color; fruit shape, size, and color; and color distribution. The objective of this study was to develop a core set of brinjal germplasm to facilitate access, conservation, and utilization. Germplasm accessions (1798) were evaluated in 2005 and 2006. Data were recorded for 28 morphological (14 qualitative and 14 quantitative) descriptors. The accessions were classified into 15 groups based on the regions and continents of their origin. Ten percent accessions were allocated to different groups, in direct proportion to the diversity summed across all qualitative descriptors in a group. From each group, accessions were selected by the “principal component score strategy” (PCSS). A comparison of means, variances, and phenotypic correlations for quantitative descriptors, and the Shannon–Wiener Diversity Index (H′) for qualitative descriptors indicated that the genetic variation for these descriptors was conserved in the core set. This core set can be evaluated intensively for agronomic traits, economic traits including resistance to biotic and abiotic stresses to identify accessions with desirable traits for use in crop improvement research and genomic studies.

Thermosets composed of cross-linked polymers demonstrate enhanced thermal, solvent, chemical, and dimensional stability as compared to their non-cross-linked counterparts. However, these often-desirable material properties typically come at the expense of reprocessability, recyclability, and healability. One solution to this challenge comes from the construction of polymers that are reversibly cross-linked. We relied on lessons from Nature to present supramolecular polymer networks comprised of cooperative Janus-faced hydrogen bonded cross-links. A triazine-based guanine-cytosine base (GCB) with two complementary faces capable of self-assembly through three hydrogen bonding sites was incorporated into poly(butyl acrylate) to create a reprocessable and recyclable network. Rheological experiments and dynamic mechanical analysis (DMA) were employed to investigate the flow behavior of copolymers with randomly distributed GCB units of varying incorporation. Our studies revealed that the cooperativity of multiple hydrogen bonding faces yields excellent network integrity evidenced by a rubbery plateau that spanned the widest temperature range yet reported for any supramolecular network. To verify that each Janus-faced motif engages in multiple cross-links, we studied the effects of local concentration of the incorporated GCB units within the polymer chain. Mechanical strength improved by colocalizing the GCB within a block copolymer morphology. This enhanced performance revealed that the number of effective cross-links in the network increased with the local concentration of hydrogen bonding units. Overall, this study demonstrates that cooperative noncovalent interactions introduced through Janus-faced hydrogen bonding moieties confers excellent network stability and predictable viscoelastic flow behavior in supramolecular networks.

1.The effect of selected drugs and various inorganic ions on ventricular fibrillation and mortality following experimental coronary artery occlusion has been investigated.2.Control mortality of 80 per cent and early fibrillation of 30 per cent was obtained following ligation of the left anterior descending coronary artery immediately at its origin.3.When coronary occlusion was delayed for 20 days post-pericardotomy in three animals there was no mortality and two of the three animals failed to demonstrate any change in the pre and postocclusion electrocardiogram.4.Mortality of 80 per cent and fibrillation of 40 per cent resulted when acidosis was produced by hydrochloric acid.5.Mortality of 80 per cent and fibrillation of 60 per cent resulted when alkalosis was produced by the infusion of sodium bicarbonate.6.A mortality rate of 60 per cent and a fibrillation rate of 60 per cent resulted when hyperkaliemia was produced.7.Hypercalcemia produced a mortality of 80 per cent and fibrillation of 60 per cent.8.Following the infusion of a relatively small amount of sodium chloride an unexpected 100 per cent mortality and 80 per cent fibrillation rate resulted.9.A mortality rate of 100 per cent and a fibrillation rate of 100 per cent followed the infusion of procaine.10.The intravenous administration of papaverine produced mortality and fibrillation rates of 60 per cent.11.Quinidine administered intravenously yielded a mortality rate of 60 per cent and fibrillation rate of 60 per cent.12.The influence of infusion of certain ions and drugs upon the concentration of other ions was determined.13.It would appear from this study that if potassium is the excitatory agent for ventricular fibrillation that myocardial potassium in ischemia is unaffected by the plasma concentration of potassium and is on a metabolic basis.14.If potassium is the agent inciting ventricular fibrillation it would appear from this study that myocardial metabolism of potassium in myocardial ischemia is unaffected by blood pH insofar as decreasing early fibrillation is concerned.15.None of the drugs or ions employed in this study showed any beneficial effect on reducing mortality or ventricular fibrillation following coronary artery occlusion.We gratefully acknowledge the electrocardiographic interpretation of Dr. Thomas M. Blake.