Precise Atomic Structures of two Important Molecules in Biochemistry:

This work celebrates the “International Year of Chemistry – 2011”, by providing “for the first time”, the structures at the atomic level of two important molecules, namely, ascorbic acid and aspirin. Ascorbic acid, also known as vitamin C, was discovered as a cure for scurvy which claimed many human lives and hence got its name. It is also supposed to be an antioxidant and to prevent flu. Aspirin is synthesized from salicylic acid and is widely used as a remedy for flu and has other medical uses such as saving the lives of cardiac patients as an anticoagulant of blood. The biochemistry and chemistry of both these compounds have been evolving for nearly a century ever since their discoveries. Here, the atomic structures of these compounds have been presented where the known lengths of the various chemical bonds are exact sums of the appropriate radii of the adjacent atoms

N-(2-Chloro­phen­yl)-N′-(2-methyl­phen­yl)succinamide

In the title compound, C17H17ClN2O2, the asymmetric unit contains half a mol­ecule with a centre of symmetry at the mid-point of the central C—C bond. The conformations of the amide O atoms are anti to the methyl­ene atoms. Further, the N—H bonds in the amide fragments are anti to the ortho-chloro/methyl groups in the adjacent benzene rings. The dihedral angle between the benzene ring and the NH—C(O)—CH2 segment in the two halves of the mol­ecule is 62.0 (2)°. In the crystal, a series of N—H⋯O inter­molecular hydrogen bonds link the mol­ecules into column-like infinite chains along the a axis. The methyl and Cl groups are disordered with respect to the ortho positions of the benzene ring, with site-occupation factors of 0.5 each

Random Network Behaviour of Protein Structures

Geometric and structural constraints greatly restrict the selection of folds adapted by protein backbones, and yet, folded proteins show an astounding diversity in functionality. For structure to have any bearing on function, it is thus imperative that, apart from the protein backbone, other tunable degrees of freedom be accountable. Here, we focus on side-chain interactions, which non-covalently link amino acids in folded proteins to form a network structure. At a coarse-grained level, we show that the network conforms remarkably well to realizations of random graphs and displays associated percolation behavior. Thus, within the rigid framework of the protein backbone that restricts the structure space, the side-chain interactions exhibit an element of randomness, which account for the functional flexibility and diversity shown by proteins. However, at a finer level, the network exhibits deviations from these random graphs which, as we demonstrate for a few specific examples, reflect the intrinsic uniqueness in the structure and stability, and perhaps specificity in the functioning of biological proteins.Comment: Expanded version available in Molecular BioSystem

Improving the Performance of Mobile Ad Hoc Network Using a Combined Credit Risk and Collaborative Watchdog Method

In mobile ad hoc networks nodes can move freely and link node failures occur frequently This leads to frequent network partitions which may significantly degrade the performance of data access in ad hoc networks When the network partition occurs mobile nodes in one network are not able to access data hosted by nodes in other networks In mobile ad hoc network some nodes may selfishly decide only to cooperate partially or not at all with other nodes These selfish nodes could then reduce the overall data accessibility in the network In this work the impact of selfish nodes in a mobile ad hoc network from the perspective of replica allocation is examined We term this selfish replica allocation A combined credit risk method collaborative watchdog is proposed to detect the selfish node and also apply the SCF tree based replica allocation method to handle the selfish replica allocation appropriately The proposed method improves the data accessibility reduces communication cost and average query delay and also to reduce the detection time and to improve the accuracy of watchdogs in the collaborative metho

N-(4-Methyl­phen­yl)succinimide

In the mol­ecule of the title compound, C11H11NO2, the dihedral angle between the aromatic ring and the amide segment is 57.3 (1)°

Growth behavior of fibroblasts influenced by small changes in polymer structure

Polymers are a promising class of biomaterials that can be engineered to meet specific end use requirements. The order and processing history of the polymer, which would alter the molecular orientation of the material could have a significant contribution towards cellular attachment and in turn, cell growth on the particular polymer. Surface properties of the material were considered to directly influence the properties of the adherent cells including cellular growth and reorganization. The present study is aimed at comparing cell growth on polyarylates with that of polylactic acid in their original state or by introducing small changes in the surface structure of the polymers, by adopting different processing techniques (i.e. drawn and undrawn forms). Though, it is the most widely used scaffold, polylactic acid has been found to degrade faster and produce acidic end products, making it unsuitable for many applications. The two polyarylates chosen for the study were poly (DTD) dodecandioate and poly (DTE) adipate taken from the two extreme positions of the combinatorial library developed by Prof.J.Kohn. Thermal analysis techniques were used to study the molecular structure of the material. Higher degradation rate, less water uptake in the aqueous environment and less acidic end products were obtained from the two polyarylates as compared to polylactic acid. There was a significant difference in the growth rate of the fibroblasts on the drawn and the undrawn forms of the (12,10)-polyarylate, suggesting that its behavior could be correlated to the number of structural conversions existing in the polymer

Moving from Interprofessional Disarticulation to Transformative Dialogue and Action: Examining a Transdisciplinary Process to Address Equitable Access to High Quality Maternity Care in North America

Maternity providers in North America are in conflict about birth place, debating issues related to safety, autonomy, and quality of care. Very little is known about how birth place interacts with experience and outcomes of maternity care, or about how to resolve these differences among provider disciplines within established health care systems. A multi-stakeholder group of leaders convened at a series of Home Birth Summits in the United States to delineate a Common Ground Agenda, including nine priority areas for action and research. The aim of this doctoral study was to examine how and why this transdisciplinary process generated new evidence and tools that can improve maternity services. Methods I synthesized the results of four original research studies using a range of methodologies as appropriate to the study topic. In the Canadian Birth Place Study, I examine mixed methods data on provider attitudes to place of birth. In the Changing Childbirth in British Colombia (BC) and Giving Voice to Mothers studies, psychometric analysis cross-sectional survey data led to development of four new person-centered measures of experience of maternity care. In the Access and Integration Maternity Care Mapping Study, a Delphi study created a scoring system (MISS) to assess midwifery integration. Correlation and regression analyses elicit linkages between integration and key maternal-newborn outcomes. Finally, I triangulated results of these studies within the Taming Wicked Problems Framework, to elicit an underlying and contributory factor for effective transdisciplinary action. Results Among maternity care providers (n=825), 84% of variance in attitudes to home birth was attributable to provider type alone. Women from diverse backgrounds (n=2051, 3586 pregnancies) reported reduced autonomy and respect when cared for by physicians and when 9 giving birth in institutional settings. Among women in the United States (US) (n=2700), disparities in experiences of care, including mistreatment, links to race, socioeconomic status, place of birth and type of provider. U.S. states with higher midwifery integration and greater access to home birth reported significantly fewer adverse maternal-newborn outcomes and significantly higher rates of physiologic birth. Discussion The participatory approach and synthesis of outcomes of these studies was essential to understand and address inequities in experience and access to quality maternity health services in the US. Person-centered care emerged as a hidden common value that informed a transdisciplinary research process, and community-responsive knowledge translation outputs. Conclusion Increasing knowledge among all types of providers about quality and safety of birth place, and person-centered care, could improve outcomes across birth settings. The Summit process of transdisciplinary engagement reduced interprofessional conflict and facilitated cocreation of evidence and tools that improve quality, safety, and accountability in North American maternity care

Making the pandemic palatable, one food post at a time

Journal #67 from Media Rise's Quarantined Across Borders Collection by Anthony Ramirez. From India. Quarantined in United States. Story on food and culture.This blog post explores the motives, meaning, and role of food and the sharing of food and food pictures during this pandemic.Media Rise Publications. Quarantined Across Borders Collection. Edited by Dr Srividya "Srivi" Ramasubramanian