Analytica

About: Analytica is a based out in . It is known for research contribution in the topics: Mass spectrometry & Population. The organization has 406 authors who have published 548 publications receiving 18172 citations.

Electrospray ionization–principles and practice

Abstract: Chemistry has its origins as a quantitative science in the careful weighing of products and reactants by Lavoisier and his followers beginning some 200 years ago. Ever since then, the constantly evolving gravimetric balance has been a faithful servant of the laboratory chemist and has played a major role in developing the analytical methods that are the foundation of contemporary chemical science. Perhaps the ultimate stage in the evolution of that balance is represented by the modern mass spectrometer. It is able to determine with high precision the masses of individual atoms and molecules by transforming them into ions and measuring the response of their trajectories in vacuo to various combinations of electric and magnetic fields. Clearly, the sine qua non of such mass determination is the transformation of analyte atoms and molecules from their initial state in a sample to ions in vacuo ready for ”weighing.” Over the years, ingenious investigators have produced a variety of methods for achieving this transformation. One of them, electrospray ( E S ) ionization, has recently shown itself capable of producing intact ions, with multiple charges, from remarkably large, complex, and fragile parent species. Our assignment here is to review what has thus far been learned about this still uncommon technique and what it seems able to offer practitioners of mass spectrometric analysis. Our approach will be to set forth the present state of the ES ionization art in terms of a sort of menu of its procedures, processes, performance, and promise. Until very recently we have been almost the only group that has worked with ES ionization since the pioneering efforts of Malcolm Dole (1) some 20 years ago. Consequently, this review is more tutorial than most. Moreover, it may seem like a cook book that is overly preoccupied with the authors’ own culinary adventures. The reasoil is that many of the dishes to be described were first tried out in our own kitchen. Therefore, we earnestly urge the reader to remember what every gourmet knows: the piquancy of any dish on a bill of fare is due much less to its ingredients than to the skill of the chef whc. prepares it.

The coffee genome provides insight into the convergent evolution of caffeine biosynthesis

Abstract: Coffee is a valuable beverage crop due to its characteristic flavor, aroma, and the stimulating effects of caffeine. We generated a high-quality draft genome of the species Coffea canephora, which displays a conserved chromosomal gene order among asterid angiosperms. Although it shows no sign of the whole-genome triplication identified in Solanaceae species such as tomato, the genome includes several species-specific gene family expansions, among them N-methyltransferases (NMTs) involved in caffeine production, defense-related genes, and alkaloid and flavonoid enzymes involved in secondary compound synthesis. Comparative analyses of caffeine NMTs demonstrate that these genes expanded through sequential tandem duplications independently of genes from cacao and tea, suggesting that caffeine in eudicots is of polyphyletic origin.

Dysfunctional tear syndrome: a Delphi approach to treatment recommendations.

Abstract: Purpose: To develop current treatment recommendations for dry eye disease from consensus of expert advice. Methods: Of 25 preselected international specialists on dry eye, 17 agreed to participate in a modified, 2-round Delphi panel approach. Based on available literature and standards of care, a survey was presented to each panelist. A two-thirds majority was used for consensus building from responses obtained. Treatment algorithms were created. Treatment recommendations for different types and severity levels of dry eye disease were the main outcome. Results: A new term for dry eye diseasewas proposed: dysfunctional tear syndrome (DTS). Treatment recommendations were based primarily on patient symptoms and signs. Available diagnostic tests were considered of secondary importance in guiding therapy. Development of algorithms was based on the presence or absence of lid margin disease and disturbances of tear distribution and clearance. Disease severity was considered the most important factor for treatment decision-making and was categorized into 4 levels. Severity was assessed on the basis of tear substitute requirements, symptoms of ocular discomfort, and visual disturbance. Clinical signs present in lids, tear film, conjunctiva, and cornea were also used for categorization of severity. Consensus was reached on treatment algorithms for DTS with and without concurrent lid disease. Conclusion: Panelist opinion relied on symptoms and signs (not tests) for selection of treatment strategies. Therapy is chosen to match disease severity and presence versus absence of lid margin disease or tear distribution and clearance disturbances.

Global Mortality Estimates for the 2009 Influenza Pandemic from the GLaMOR Project: A Modeling Study

Abstract: Background Assessing the mortality impact of the 2009 influenza A H1N1 virus (H1N1pdm09) is essential for optimizing public health responses to future pandemics. The World Health Organization reported 18,631 laboratory-confirmed pandemic deaths, but the total pandemic mortality burden was substantially higher. We estimated the 2009 pandemic mortality burden through statistical modeling of mortality data from multiple countries.