Novel polymers of intrinsic microporosity

A series of novel network and ladder microporous polymers was prepared by conventional nucleophilic aromatic substitution polycondensation reaction between catechol-containing compounds and activated <italic>o</italic>-fluoro aryl monomers. The building blocks of these prepared polymers consist of rigid compounds such as triptycene, triphenylene or hexaazatriphenylene, which have unique structure properties that force the final product to adopt a large internal free volume within the structure and induce porosity. Also, a series of biphenyl-based polymers was prepared exploiting the severely rotationally hindered structure resulting from steric substitution. The preparation of microporous materials was extended further by using the macrocyclic compounds (such as phthalocyanine) as building blocks to synthesise several macrocyclic-based polymers, taking advantage of the ridged non-planar special geometry of the starting building blocks. The Yamamoto coupling reaction was used to prepare microporous polymers by the self-coupling of various aryl bromide compounds. The resulting polymers were characterised by their elemental and nitrogen adsorption analysis, which showed these materials to possess considerable surface area in each case. The prepared polymers exhibit good thermal stability as indicated by thermogravimetric analysis, the distinct sharing feature of all materials prepared in this study is the rigidity of the resulting polymer architecture originating from severely restricted rotational freedom along the polymer backbone.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Is There Chronic Brain Damage in Retired NFL Players? Neuroradiology, Neuropsychology, and Neurology Examinations of 45 Retired Players

BACKGROUND: Neuropathology and surveys of retired National Football League (NFL) players suggest that chronic brain damage is a frequent result of a career in football. There is limited information on the neurological statuses of living retired players. This study aimed to fill the gap in knowledge by conducting in-depth neurological examinations of 30- to 60-year-old retired NFL players. HYPOTHESIS: In-depth neurological examinations of 30- to 60-year-old retired players are unlikely to detect objective clinical abnormalities in the majority of subjects. STUDY DESIGN: A day-long medical examination was conducted on 45 retired NFL players, including state-of-the-art magnetic resonance imaging (MRI; susceptibility weighted imaging [SWI], diffusion tensor imaging [DTI]), comprehensive neuropsychological and neurological examinations, interviews, blood tests, and APOE (apolipoprotein E) genotyping. LEVEL OF EVIDENCE: Level 3. METHODS: Participants\u27 histories focused on neurological and depression symptoms, exposure to football, and other factors that could affect brain function. The neurological examination included Mini-Mental State Examination (MMSE) evaluation of cognitive function and a comprehensive search for signs of dysarthria, pyramidal system dysfunction, extrapyramidal system dysfunction, and cerebellar dysfunction. The Beck Depression Inventory (BDI) and Patient Health Questionnaire (PHQ) measured depression. Neuropsychological tests included pen-and-paper and ImPACT evaluation of cognitive function. Anatomical examination SWI and DTI MRI searched for brain injuries. The results were statistically analyzed for associations with markers of exposure to football and related factors, such as body mass index (BMI), ethanol use, and APOE4 status. RESULTS: The retired players\u27 ages averaged 45.6 +/- 8.9 years (range, 30-60 years), and they had 6.8 +/- 3.2 years (maximum, 14 years) of NFL play. They reported 6.9 +/- 6.2 concussions (maximum, 25) in the NFL. The majority of retired players had normal clinical mental status and central nervous system (CNS) neurological examinations. Four players (9%) had microbleeds in brain parenchyma identified in SWI, and 3 (7%) had a large cavum septum pellucidum with brain atrophy. The number of concussions/dings was associated with abnormal results in SWI and DTI. Neuropsychological testing revealed isolated impairments in 11 players (24%), but none had dementia. Nine players (20%) endorsed symptoms of moderate or severe depression on the BDI and/or met criteria for depression on PHQ; however, none had dementia, dysarthria, parkinsonism, or cerebellar dysfunction. The number of football-related concussions was associated with isolated abnormalities on the clinical neurological examination, suggesting CNS dysfunction. The APOE4 allele was present in 38% of the players, a larger number than would be expected in the general male population (23%-26%). CONCLUSION: MRI lesions and neuropsychological impairments were found in some players; however, the majority of retired NFL players had no clinical signs of chronic brain damage. CLINICAL RELEVANCE: These results need to be reconciled with the prevailing view that a career in football frequently results in chronic brain damage

In situ, real-time visualization of electrochemistry using magnetic resonance imaging

The drive to develop better electrochemical energy storage devices requires the development of not only new materials, but also better understanding of the underpinning chemical and dynamical processes within such devices during operation, for which new analytical techniques are required. Currently, there are few techniques that can probe local composition and transport in the electrolyte during battery operation. In this paper, we report a novel application of magnetic resonance imaging (MRI) for probing electrochemical processes in a model electrochemical cell. Using MRI, the transport and zinc and oxygen electrochemistry in an alkaline electrolyte, typical of that found in zinc-air batteries, are investigated. Magnetic resonance relaxation maps of the electrolyte are used to visualize the chemical composition and electrochemical processes occurring during discharge in this model metal-air battery. Such experiments will be useful in the development of new energy storage/conversion devices, as well as other electrochemical technologies

Uso de la lama del lago “El Nihuil”, digestión anaeróbica para obtención de biogás

Esta investigación consiste en mitigar los efectos naturales y artificiales causados en un lago de una localidad turística de la provincia de Mendoza. Una de las soluciones más efectivas para este caso es la poda de las algas del mismo. Pero ésta acarrea el inconveniente: deposición final de estos desechos. Se propuso aprovechar la degradación de estas plantas en forma anaeróbica. Se realizaron pruebas a escala, las que comprenden dos etapas. En la primera se verificó la producción de gas combustible y se realizaron análisis químicos de la materia antes y después de la degradación. En la segunda se midió el gas producido. Al final de este proceso se consigue también una disminución de la masa residual, la que a su vez puede ser aprovechada como fertilizante y/o mejorador de suelos. En la actualidad es fundamental encontrar nuevas fuentes de energías que contaminen menos, y un mayor aprovechamiento de los residuos.This project consists in mitigating the natural and artificial effects caused in a touristic village’s lake from Mendoza. One of the best solutions is pruning alga of the lake. But this one produces another inconvenient which is his final deposition. The solution propounded is: use it as a source of biogas degrading this plant. The anaerobic digestion was studied, and then there were done small experiment in two stages. In the first one was verified the combustible gas production. There was done a chemical analysis of this matter after the degradation and before it. In the second part of the experience we measured the gas produced. At the end of this process we had less waste, and this one can be used as fertilizer and to improve ground mechanical properties. It is truly important to found new sources of energy that are less polluting and a better use of waste.Asociación Argentina de Energías Renovables y Medio Ambiente (ASADES

Uso de la lama del lago “El Nihuil”, digestión anaeróbica para obtención de biogás

Esta investigación consiste en mitigar los efectos naturales y artificiales causados en un lago de una localidad turística de la provincia de Mendoza. Una de las soluciones más efectivas para este caso es la poda de las algas del mismo. Pero ésta acarrea el inconveniente: deposición final de estos desechos. Se propuso aprovechar la degradación de estas plantas en forma anaeróbica. Se realizaron pruebas a escala, las que comprenden dos etapas. En la primera se verificó la producción de gas combustible y se realizaron análisis químicos de la materia antes y después de la degradación. En la segunda se midió el gas producido. Al final de este proceso se consigue también una disminución de la masa residual, la que a su vez puede ser aprovechada como fertilizante y/o mejorador de suelos. En la actualidad es fundamental encontrar nuevas fuentes de energías que contaminen menos, y un mayor aprovechamiento de los residuos.This project consists in mitigating the natural and artificial effects caused in a touristic village’s lake from Mendoza. One of the best solutions is pruning alga of the lake. But this one produces another inconvenient which is his final deposition. The solution propounded is: use it as a source of biogas degrading this plant. The anaerobic digestion was studied, and then there were done small experiment in two stages. In the first one was verified the combustible gas production. There was done a chemical analysis of this matter after the degradation and before it. In the second part of the experience we measured the gas produced. At the end of this process we had less waste, and this one can be used as fertilizer and to improve ground mechanical properties. It is truly important to found new sources of energy that are less polluting and a better use of waste.Asociación Argentina de Energías Renovables y Medio Ambiente (ASADES