Preliminary field screening of maize landrace germplasm from northeastern Mexico under high temperatures

Northeastern Mexico has a wide variety of maize landraces that have not been characterized, and landraces vari¬eties may be a good source of new allelic diversity for useful traits. This study evaluated 28 accessions from Tam¬aulipas, in Northeast Mexico, chosen by phenology and for agronomic characteristics to represent the diversity of germplasm in the collection and agro-ecosystems of this area. They were evaluated under high temperature in the field as a basis for an efficient use of this maize germplasm in a breeding program; in particular we investigated changes in agronomic characteristics affected by high temperatures in all growing seasons. Results indicated that in late planting dates air temperatures become excessively high during the flowering period and growing season; in these conditions a loss in grain yield can be sustained. In this study, the loss initially manifests itself as a reduc¬tion in grain yield (> 32%) because of fewer grains per ear (>26%). Landrace maize accessions C-3030, C-3049, C-3015, Pob. I, Pob. II, ZEM-148 and C-4050 were identified with high relative yield and yield components traits under high temperature conditions. These accessions have greater agronomic stability, and also are potential donors of genes to improve maize tolerance to high temperature

Selective Reagent Ion Mass Spectrometric Investigations of the Nitroanilines

This paper presents an investigation of proton and charge transfer reactions to 2-, 3- and 4-nitroanilines (C6H6N2O2) involving the reagent ions H3O+·(H2O)n (n=0, 1 and 2) and O2+, respectively, as a function of reduced electric field (60-240 Td), using Selective Reagent Ion-Time-of-Flight-Mass Spectrometry (SRI-ToF-MS). To aid in the interpretation of the H3O+·(H2O)n experimental data, the proton affinities and gas-phase basicities for the three nitroaniline isomers have been determined using density functional theory. These calculations show that proton transfer from both the H3O+ and H3O+·H2O reagent ions to the nitroanilines will be exoergic and hence efficient, with the reactions proceeding at the collisional rate. For proton transfer from H3O+ to the NO2 sites, the exoergicities are 171 kJ mol-1 (1.8 eV), 147 kJ mol-1 (1.5 eV) and 194 kJ mol-1 (2.0 eV) for 2-, 3- and 4-nitroanilines, respectively. Electron transfer from all three of the nitroanilines is also significantly exothermic by approximately 4 eV. Although a substantial transfer of energy occurs during the ion/molecule reactions, the processes are found to predominantly proceed via non-dissociative pathways over a large reduced electric field range. Only at relatively high reduced electric fields (>180 Td) is dissociative proton and charge transfer observed. Differences in fragment product ions and their intensities provide a means to distinguish the isomers, with proton transfer distinguishing 2-nitroaniline (2-NA) from 3- and 4-NA, and charge transfer distinguishing 4-NA from 2- and 3-NA, thereby providing a means to enhance selectivity using SRI-ToF-MS.(VLID)4826158Version of recor

Applications of Direct Injection Soft Chemical Ionisation-Mass Spectrometry for the Detection of Pre-blast Smokeless Powder Organic Additives

Analysis of smokeless powders is of interest from forensics and security perspectives. This article reports the detection of smokeless powder organic additives (in their pre-detonation condition), namely the stabiliser diphenylamine and its derivatives 2-nitrodiphenylamine and 4-nitrodiphenylamine, and the additives (used both as stabilisers and plasticisers) methyl centralite and ethyl centralite, by means of swab sampling followed by thermal desorption and direct injection soft chemical ionisation-mass spectrometry. Investigations on the product ions resulting from the reactions of the reagent ions H3O+ and O2+ with additives as a function of reduced electric field are reported. The method was comprehensively evaluated in terms of linearity, sensitivity and precision. For H3O+, the limits of detection (LoD) are in the range of 41-88 pg of additive, for which the accuracy varied between 1.5 and 3.2%, precision varied between 3.7 and 7.3% and linearity showed R20.9991. For O2+, LoD are in the range of 72 to 1.4 ng, with an accuracy of between 2.8 and 4.9% and a precision between 4.5 and 8.6% and R20.9914. The validated methodology was applied to the analysis of commercial pre-blast gun powders from different manufacturers.(VLID)4826148Accepted versio

Metagenomic ene-reductases for the bioreduction of sterically challenging enones

Ene-reductases (ERs) of the Old Yellow Enzyme family catalyse asymmetric reduction of activated alkenes providing chiral products. They have become an important method in the synthetic chemists' toolbox offering a sustainable alternative to metal-catalysed asymmetric reduction. Development of new biocatalytic alkene reduction routes, however needs easy access to novel biocatalysts. A sequence-based functional metagenomic approach was used to identify novel ERs from a drain metagenome. From the ten putative ER enzymes initially identified, eight exhibited activities towards widely accepted mono-cyclic substrates with several of the ERs giving high reaction yields and stereoselectivities. Two highly performing enzymes that displayed excellent co-solvent tolerance were used for the stereoselective reduction of sterically challenging bicyclic enones where the reactions proceeded in high yields, which is unprecedented to date with wild-type ERs. On a preparative enzymatic scale, reductions of Hajos–Parish, Wieland–Miescher derivatives and a tricyclic ketone proceeded with good to excellent yields

Reclaiming comprehensive public health

Global and national responses to the COVID-19 pandemic highlight a long-standing tension between biosecurity-focused, authoritarian and sometimes militarised approaches to public health and, in contrast, comprehensive, social determinants, participatory and rights-based approaches. Notwithstanding principles that may limit rights in the interests of public health and the role of central measures in some circumstances, effective public health in a protracted pandemic like COVID-19 requires cooperation, communication, participatory decision-making and action that safeguards the Siracusa principles, respect for people’s dignity and local-level realities and capacities. Yet there is mounting evidence of a dominant response to COVID-19 where decisions are being made and enforced in an overcentralised, non-transparent, top-down manner, often involving military coercion and abuse in communities, even while evidence shows the long-term harm to public health and human rights. In contrast, experiences of comprehensive, equity-focused, participatory public health approaches, which use diverse sources of knowledge, disciplines and capabilities, show the type of public health approach that will be more effective to meet the 21st century challenges of pandemics, climate, food and energy crises, growing social inequality, conflict and other threats to health

Renal vasculitis in Colombia

A retrospective review of publications about primary vasculitis cases was performed from the Colombian medical literature, the clinical and pathological features are described.The Renal vasculitis occurred in 33.9% of cases of primary vasculitis reviewed and was more frequent in women. The main clinical, hematological, immunological variables and nephropathology and immunosuppressive treatments used findings are described

La estrella cautiba cuya hermosa diuisa se descubre a la reboluccion [sic] de los siete Orbes y estrellas errantes [Manuscrito]: dialogo en que hablan Don Prudencio filosopho y Don Silbio prophesor de letras humanas ...

Dedicatoria dirigida a don Luis Méndez de Haro, Conde Duque de Olivares, [7] h.Firma autógrafa de la dedicatoriaSumario: Al final de la obra "Tabla de los paragrafos y estancias de la Estrella Cautiva", [4] h.: es un índice que contempla fusionadas en una sola obra, con foliación continua, las dos obras: la Estrella cautiva y La Historia de Estella. Según este índice, la obra estaba formada por 4 "estancias": la primera dividida en 24 "parágrafos", la segunda en 8 discursos, la tercera en 14 parágrafos y la cuarta en 11 parágrafos. Este mss. contiene el texto de la segunda estancia completa, los parágrafos 1-3 de la tercera y la cuarta estancia completa que, al parecer, una vez desgajada la obra conjunta, dan lugar al trabajo titulado "La Estrella cautiva". Mientras que las estancias primera y tercera que indica la Tabla dan lugar al trabajo titulado "Excelencias y antigüedad de Estella" que se corresponde con las copias mss. existentes de la "Historia de la Ciudad de Estella y su Merindad" de este autorApostilla marginal en r. de h. [1]: "Las excelencias y antiguedad de Estella yvan [sic] encadenadas con este tratadillo y sean [sic] separado del [sic] porque vaya distinto el un asumpto del otro"Dedicatoria precede a información complementaria del tít.Apostilla marginal en v. de h. [107]: "acavosse esta obra Lunes a la una de medio dia 14 de Março. Año 1644"Fecha tomada de port., Año 1648Por la biografía del autor, escrito probablemente en EstellaReclamos horizontales en todas las h.Foliación original: 115-175, 265-310 h.Apostillas marginales: notas bibliográficas y explicativasTexto tachado en h.

Star forming dwarf galaxies

Star forming dwarf galaxies (SFDGs) have a high gas content and low metallicities, reminiscent of the basic entities in hierarchical galaxy formation scenarios. In the young universe they probably also played a major role in the cosmic reionization. Their abundant presence in the local volume and their youthful character make them ideal objects for detailed studies of the initial stellar mass function (IMF), fundamental star formation processes and its feedback to the interstellar medium. Occasionally we witness SFDGs involved in extreme starbursts, giving rise to strongly elevated production of super star clusters and global superwinds, mechanisms yet to be explored in more detail. SFDGs is the initial state of all dwarf galaxies and the relation to the environment provides us with a key to how different types of dwarf galaxies are emerging. In this review we will put the emphasis on the exotic starburst phase, as it seems less important for present day galaxy evolution but perhaps fundamental in the initial phase of galaxy formation.Comment: To appear in JENAM Symposium "Dwarf Galaxies: Keys to Galaxy Formation and Evolution", P. Papaderos, G. Hensler, S. Recchi (eds.). Lisbon, September 2010, Springer Verlag, in pres