Analyses of Aliphatic Aldehydes and Ketones in Carbonaceous Chondrites

Aliphatic aldehydes and ketones are essential building blocks for the synthesis of more complex organic compounds. In spite of their potentially key role as precursors of astrobiologically-important molecules, such as amino acids and carboxylic acids, this family of compounds has scarcely been evaluated in carbonaceous chondrites. The paucity of such analyses likely derives from the low concentration of aldehydes and ketones in the meteorites, and from the currently used chromatographic methodologies that have not been optimized for meteorite analysis. In this work, we report the development of a novel analytical method to quantify the molecular distribution and compound-specific isotopic analysis of 29 aliphatic aldehydes and ketones. Using this method, we have investigated the molecular distribution and 13C-isotopic composition of aldehydes and ketones in ten carbonaceous chondrites from the CI, CM, CR and CV groups. The total concentration of carbonyl compounds ranged from 130 to 1000 nmolg-1 of meteorite, with formaldehyde, acetaldehyde, and acetone being the most abundant species in all investigated samples. The 13C-isotopic values ranged from 67 to +64 and we did not observe clear relationships between 13C-content and molecular weight. Accurately measuring the relative abundances, determining the molecular distribution, and isotopic composition of chondritic organic compounds is central in assessing both their formation chemistry and synthetic relationships

Pathways to Meteoritic Glycine and Methylamine

Glycine and methylamine are meteoritic water-soluble organic compounds that provide insights into the processes that occurred before, during, and after the formation of the Solar System. Both glycine and methylamine and many of their potential synthetic precursors have been studied in astrophysical environments via observations, laboratory experiments, and modeling. Despite these studies, the synthetic mechanisms for their formation leading to their occurrence in meteorites remain poorly understood. Typical 13C-isotopic values (13C) of meteoritic glycine and methylamine are 13C-enriched relative to their terrestrial counterparts; thus, analyses of their stable carbon isotopic compositions (13C/12C) may be used not only to assess terrestrial contamination in meteorites but also to provide information about their synthetic routes inside the parent body. Here, we examine potential synthetic routes of glycine and methylamine from a common set of precursors present in carbonaceous chondrite meteorites, using data from laboratory analyses of the well-studied CM2 Murchison meteorite. Several synthetic mechanisms for the origins of glycine and methylamine found in carbonaceous chondrites may be possible, and the prevalence of these mechanisms will largely depend on (a) the molecular abundance of the precursor molecules and (b) the levels of processing (aqueous and thermal) that occurred inside the parent body. In this work, we also aim to contextualize the current knowledge about gas-phase reactions and irradiated ice grain chemistry for the synthesis of these species through parent body processes. Our evaluation of various mechanisms for the origins of meteoritic glycine and methylamine from simple species shows what work is still needed to evaluate both the abundances and isotopic compositions of simpler precursor molecules from carbonaceous chondrites as well as the effects of parent body processes on those abundances and isotopic compositions. The analyses presented here combined with the indicated measurements will aid a better interpretation of quantitative analysis of reaction rates, molecular stability, and distribution of organic products from laboratory simulations of interstellar ices, astronomical observations, and theoretical modeling

Molecular Distribution, 13C-Isotope, and Enantiomeric Compositions of Carbonaceous Chondrite Monocarboxylic Acids

The watersoluble organic compounds in carbonaceous chondrite meteorites constitute a record of the synthetic reactions occurring at the birth of the solar system and those taking place during parent body alteration and may have been important for the later origins and development of life on Earth. In this present work, we have developed a novel methodology for the simultaneous analysis of the molecular distribution, compoundspecific 13C, and enantiomeric compositions of aliphatic monocarboxylic acids (MCA) extracted from the hotwater extracts of 16 carbonaceous chondrites from CM, CR, CO, CV, and CK groups. We observed high concentrations of meteoritic MCAs, with total carbon weight percentages which in some cases approached those of carbonates and insoluble organic matter. Moreover, we found that the concentration of MCAs in CR chondrites is higher than in the other meteorite groups, with acetic acid exhibiting the highest concentration in all samples. The abundance of MCAs decreased with increasing molecular weight and with increasing aqueous and/or thermal alteration experienced by the meteorite sample. The 13C isotopic values of MCAs ranged from 52 to +27, and aside from an inverse relationship between 13C value and carbon straightchain length for C3C6 MCAs in Murchison, the 13Cisotopic values did not correlate with the number of carbon atoms per molecule. We also observed racemic compositions of 2methylbutanoic acid in CM and CR chondrites. We used this novel analytical protocol and collective data to shed new light on the prebiotic origins of chondritic MCAs

Analysis of Volatile Organic Compounds in the Apollo Next Generation Sample Analysis (ANGSA) 73002 Core Sample

Understanding the organic content of lunar regolith was an early priority upon the return of Apollo samples, with amino acids being of special interest because of their importance to life on Earth and their astrobiological relevance. Many initial studies focused on the detection of amino acids in these samples and attempts to determine the origin of those compounds. Although no consensus on the origin of the amino acids was reached in those early studies, more recent work determined that the detected amino acids originated from both terrestrial contamination and meteoritic or cometary in fall to the lunar surface. A majority of the amino acids in the Apollo samples studied originated from precursor molecules, either indigenous to the lunar samples or contaminants, that reacted during the water extraction and acid hydrolysis process for analysis in the laboratory, but the identities of the amino acid precursors still remain poorly understood. Such precursors could include hydrogen cyanide (HCN) and other volatile organic compounds such as amines, carboxylic acids, or aldehydes and ketones. The identities of these compounds, as well as the effects of years of curation on their abundances in lunar regolith samples stored at ambient temperature under nitrogen gas purge, are not clear. The specially curated samples available through the Apollo Next Generation Sample Analysis (ANGSA) program provide a unique opportunity to use state-of- the-art analytical techniques to examine previously unstudied lunar materials. The ANGSA samples include three types of samples: 1) samples stored frozen since <1 month after Earth arrival; 2) samples stored under helium; and 3) a double drive tube collected by Apollo 17 astronauts, with the bottom portion of the drive tube sealed under vacuum on the Moon and never opened. In contrast to the typically curated Apollo samples that have been kept for decades at room temperature under flowing nitrogen purge that may have significantly reduced the abundance of volatiles, the vacuum-sealed and frozen samples may have enhanced preservation of these volatiles. Our initial investigation examines amino acids and their potential volatile precursors, including hydrogen cyanide (HCN), aldehydes, ketones, amines, and mono-carboxylic acids, in a sample from the top portion of the Apollo 17 double drive tube. These results will aid in understanding the lunar abundances of these molecules and will also be compared to future analyses of other drive tube and frozen ANGSA samples

William James Morton (1845 – 1920): Like Father, Like Son?

William Thomas Green Morton, the man most commonly associated with the introduction of anesthesia in 1846, fathered William James Morton. William James Morton’s contributions to society were substantial. He conducted pioneering work in radiology, radiation oncology, and therapeutic electricity. He authored numerous textbooks and articles, and he was an editor of a journal on human behavior. His expertise on diamond mining led to an error in judgment that resulted in a felony conviction. We examine his career and contributions to society, and consider his career in light of his father, William Thomas Green Morton

Horace Wells Memorials in the City of Hartford, Connecticut

Introduction: Hartford, capital city of Connecticut was where Horace Wells conducted most of his work on the only anesthetic gas still used in clinical practice since the 19th century – nitrous oxide. Wells was born and raised in Hartford, Vermont, studied dentistry in Boston and established his practice in Hartford, Connecticut. Various icons celebrating Wells’ unique contributions in discovering the analgesic properties of nitrous oxide are located throughout this city. Materials and Methods: We consulted staff at Connecticut Historical Society (CHS) and at Hartford Medical Society to help identify sites and artifacts in Hartford that honor Horace Wells. Thereafter, we visited and studied each of these sites. Results: In 1847, Wells wrote a pamphlet titled ‘History of the Discovery of the Application of Nitrous Oxide Gas, Ether and Other Vapors to Surgical Operations.’ (Fig. 1). In 1907, the Spanish Dental Society honored Wells by awarding the city of Hartford a silver coat of arms. (Fig. 2) After Wells’ tragic death in 1848, his friend and dental colleague, John Riggs, prepared a death mask. (Fig. 3). The original mask was used by T. H. Bartlett in 1874 to sculpt a bronze statue of Horace Wells that was erected in Bushnell Park1 (Fig. 4). Wells’ office was located on Main Street, Hartford, and a plaque has been inserted onto the modern structure that stands in its place currently (Fig. 5). Horace and Elizabeth Wells were buried initially at Hartford’s Old North Cemetery. However, in 1908, Charles T. Wells (Horace’s only son) disinterred his parents’ remains from Old North Cemetery and reinterred them at Cedar Hill Cemetery. He also commissioned sculptor Louis Potter to create a fitting memorial consisting of a large granite grave marker with a bronze plaque on the front surface, and two angel figures on either end depicting the glory of his father’s discovery.2 (Fig. 6) Charles’ efforts to recognize his father’s discovery also led him to order from Louis C. Tiffany, a stain glass window (Fig. 7) that adorns Center Congregational Church. The Chapel at Trinity College has a pew dedicated to Horace Wells (Fig. 8).3 American artist Charles Noel Flagg (1848-1916) painted a portrait of Horace Wells, and this is part of the collection at Wadsworth Atheneum Museum of Art (Fig. 9).3,4 Conclusions: The city of Hartford, Connecticut celebrates Horace Wells’ achievements with many historical monuments, gifts, books and paraphernalia; thereby remembering his role in the discovery of the anesthetic effects of nitrous oxide. His work was recognized not only in the United States, but also in Europe.

Função executiva e quociente intelectual nos pacientes com diagnóstico de esquizofrenia

A esquizofrenia tem despertado o interesse de muitos profissionais da saúde. É considerada uma síndrome clínica que afeta diversos processos, como o pensamento, a emoção, os movimentos, o comportamento; e processos cognitivos como a atenção, a memória, a linguagem e, especialmente, as funções executivas. O objetivo deste estudo foi avaliar as funções executivas nos pacientes com diagnóstico de esquizofrenia, para comprovar si há relação com o quociente intelectual. Intervieram 30 pacientes com escolaridade mínima de três anos, que estavam recebendo tratamento farmacológico, e no tinham evidência de atraso mental prévio. Aplicou-se o Wisconsin Card Sorting Tets (WCST) para avaliar as habilidades envolvidas na função executiva e a Escala de Inteligência de Weschler para adultos (WAIS) para determinar o quociente intelectual, o QI verbal, manipulador e global. Foi achado os pacientes apresentarem um deterioro global em cada uma das habilidades envolvidas na função executiva e situarem em um rango de deficiência mental na escala da inteligência. Isto confirma que mesmo se há deterioro das funções executivas e um nível baixo de quociente intelectual nos pacientes, não existe correlação entre estas duas variáveis.La esquizofrenia ha generado el interés de muchos profesionales de la salud, considerada desde un principio como un síndrome clínico que afecta diferentes procesos como el pensamiento, la emoción, los movimientos, el comportamiento, y aspectos cognitivos como la atención, la memoria, el lenguaje y especialmente las funciones ejecutivas. El objetivo del presente estudio fue evaluar las funciones ejecutivas en pacientes con diagnóstico de esquizofrenia para verificar si existe alguna relación con el Cociente Intelectual. Se tomaron 30 pacientes con un mínimo de escolaridad de tres años, que se encontraban recibiendo tratamiento farmacológico y sin evidencia de un retardo mental previo; se les aplicó el Wisconsin Card Sorting Test (WCST) para evaluar las habilidades implicadas en la función ejecutiva y la escala de Inteligencia de Weschler para adultos (WAIS) para determinar el Cociente Intelectual, CI verbal, manipulativo y global. En la población estudiada, se encontró que los pacientes presentaron un deterioro global en cada una de las habilidades implicadas en la función ejecutiva, y se ubicaron en un rango de deficiencia mental en la escala de inteligencia, confirmándose que aunque existe deterioro de las funciones ejecutivas y un nivel de cociente intelectual bajo en los pacientes, no existe correlación entre estas dos variables.Schizophrenia, considered from the beginning as a clinical syndrome that affects different processes such as thinking, emotions, movements, and behaviour, as well as cognitive aspects such as attention, memory, language and especially the executive functions, is an entity that has arisen the interest of many health professionals. The objective of the present study was to assess the above mentioned functions in patients who had been diagnosed with schizophrenia and later verify if there was a relation with their intellectual quotient. The sample for this research was composed of 30 patients with no evidence of previous mental retardation, who had studied for at least three years and who were receiving the suitable pharmacological treatment. The Wisconsin Card Sorting Test (WCST) was administered to assess the abilities involved in the executive function, and the Weschler Adult Intelligence Scale (WAIS), to determine the verbal, manipulative and global intellectual quotient (IQ). The research results showed that the patients presented a global deterioration in each one of the abilities involved in the executive function and were located within the rank of mental deficiency in the intelligence scale, thus confirming that although patients showed deterioration of the executive functions and a low level of intellectual quotient, there is no correlation between these two variables

Hydrothermal Decomposition of Amino Acids and Origins of Prebiotic Meteoritic Organic Compounds

The organic compounds found in carbonaceous chondrite meteorites provide insight into primordial solar system chemistry. Evaluating the formation and decomposition mechanisms of meteoritic amino acids may aid our understanding of the origins of life and homochirality on Earth. The amino acid glycine is widespread in meteorites and other extraterrestrial environments; other amino acids, such as isovaline, are found with enantiomeric excesses in some meteorites. The relationship between meteoritic amino acids and other compounds with similar molecular structures, such as aliphatic monoamines and monocarboxylic acids is unclear; experimental results evaluating the decomposition of amino acids have produced inconclusive results about the preferred pathways, reaction intermediates, and if the conditions applied may be compatible with those occurring inside meteoritic parent bodies. In this work, we performed extensive tandem metadynamics, umbrella sampling, and committor analysis to simulate the neutral mild hydrothermal decomposition mechanisms of glycine and isovaline and put them into context for the origins of meteoritic organic compounds. Our ab initio simulations aimed to determine free energy profiles and decomposition pathways for glycine and isovaline. We found that under our modeled conditions, methylammonium, glycolic acid, and sec-butylamine are the most likely decomposition products. These results suggest that meteoritic aliphatic monocarboxylic acids are not produced from decomposition of meteoritic amino acids. Our results also indicate that the decomposition of L-isovaline prefers an enantioselective pathway resulting in the production of (S)-sec-butylamine