N—H⋯N hydrogen bonding in 4,6-diphenyl-2-pyrimidinylamine isolated from the plant Justicia secunda (Acanthaceae)

The title compound, C₁₆H₁₃N₃, isolated from Justicia secunda (Acanthaceae), comprises two molecules (which differ slightly in conformation) in the asymmetric unit of space group P\overline 1. Intermolecular Namino-H...Npyrm interactions (Npyrm is a pyrimidine ring N atom) involve only one of the two donor amino H atoms and pyrimidine N atoms per molecule, forming dimeric units via R²₂(8) rings, with N...N distances of 3.058 (2) and 3.106 (3) Å, and N-H...N angles of 172.7 (18) and 175.8 (17)°. The dimers are linked by C-H...π(arene) contacts, with an H...centroid distance of 2.77 Å and a C-H...centroid angle of 141°

Development of an integrative model for electronic vendor relationship management for improving technological innovation, social change and sustainability performance

Vendor relationship management (VRM) is a software tool that helps to provide seamless connectivity between buyer and supplier. With the rapid development of information and communication technology (ICT) most firms have migrated to electronic VRM (EVRM) capability. Only a few studies have examined how EVRM can impact the dynamic B2B capability of firms that combine technological and social innovation in support of transitions and the achievement of business goals. There are also very few interdisciplinary studies using a range of performance matrices to explore the relationship between firms' dynamic B2B capabilities and their sustainability performance, mediated through their various sustainable growth opportunities. In this context, this study aims to develop an integrative model for B2B EVRM capability and firm sustainability. With the help of dynamic capability view (DCV) theory and related literature, a theoretical model is proposed. This model was later validated using the covariance-based structural equation modeling technique (CB-SEM), in considering 378 responses from Indian firms. The study has three main findings. First, EVRM capability significantly and positively impacts B2B dynamic relationship capability between the firm and the vendors. Second, B2B dynamic relationship management capability has a significant and positive impact on firms' sustainability performance mediated through the financial, environmental, and operational performance of the firm. And third, Environmental dynamism (ED) plays a significant role as a moderator, influencing B2B dynamic relationship management capability

S-H type waves un a sandwiched spherical model

Se estudia la propagación de la onda S-H en una capa esférica heterogénea (la densidad p y el módulo de rigidez μ varían inversamente con el cuadrado de la distancia radial (r) desde el centro, de manera tal. que la velocidad de la onda de cizalle es constante) contenida entre una corteza esférica homogénea y un núcleo esférico homogéneo. Se deducen las ecuaciones de periodo y. lo apropiado de su uso se establece mediante resultados numéricos considerando el núcleo central como (J ) sólido y (2) fluido doi: https://doi.org/10.22201/igeof.00167169p.1979.18.1.109

A note on the propagation of S-H waves in a heterogeneous isotropic Half-Space

En este artículo se determinan las velocidades, de fase y grupo de ondas S-H en un semiespacio heterogéneo, isotrópico en el cual la velocidad de ondas de cizallamiento es constante. doi: https://doi.org/10.22201/igeof.00167169p.1979.18.1.109

Overt leptin response to controlled ovarian hyperstimulation negatively correlates with pregnancy outcome in in vitro fertilization--embryo transfer cycle

Context: A critical body mass of adipose tissue is essential for the normal development of female reproductive functions. Leptin, an adipocyte-derived hormone encoded by the ′Ob′ gene has been proposed as a peripheral signal indicating the adequacy of nutritional status for reproductive functions. It is reported as a direct regulator of gametogenic and steroidogenic potential of ovary. Though leptin is widely present in reproductive tissues, its relationship to reproductive hormones is still poorly understood. Aims: Present investigation attempts to explore ovarian response to secretory profile of leptin and its impact on pregnancy outcome in women undergoing controlled ovarian hyperstimulation for in vitro fertilization and embryo transfer (IVF-ET). Settings and Design: Patients enrolled for IVF-ET underwent pituitary-ovarian suppression by ′Long Protocol′ GnRH-agonist downregulation followed by ovarian stimulation. Materials and Methods: Sera were procured at different phases of IVF-ET for the assay of estradiol, progesterone, human chorionic gonadotropin, and for leptin. Ovarian follicular fluids were also assayed for leptin. Luteinized granulosa cells were cultured in vitro to evaluate their steroidogenic potential. Statistical Analysis Used: Statistical analyses were done by student′s t-test, ANOVA, and Chi-square tests as applicable. All results were expressed as Mean ± SE. P values < 0.05 were considered significant. Results: Positive correlation was observed between serum and ovarian follicular fluid leptin. A negative correlation was noted between the serum leptin levels and endometrial thickness. Conclusions: Elevated leptin response may exert adverse impacts on pregnancy success during IVF-ET possibly by modulating uterine receptivity