Perspectives on Protection of Deep Groundwater

Most of the groundwater that supports rivers and abstractions in England derive from aquifers lying no more than 400 m below the surface. However, deeper groundwater, including springs that have their sources at depth, may also have value as a resource (for example, the hot springs at Bath) and potentially could be abstracted for other purposes. It is important to develop a better understanding of these waters and the volumes available so that they can be protected, where necessary, from activities that take place at depth such as the exploitation of onshore oil and gas. This project looked at deep subsurface activities and whether we need constraints in order to protect deep groundwaters. These constraints would depend on the value of the groundwater and the risks posed by the activities

Molybdenum Para-Terphenyl Diphosphine Complexes

This dissertation describes studies exploring the coordination chemistry and reactivity of molybdenum complexes bearing a flexible and redox non-innocent para-terphenyl diphosphine ligand. Within this context, transformations relevant to energy storage and conversion, fundamental structure function studies, and unusual group transfer reactivity are presented. Chapter 2 accounts the ability of Mo para-terphenyl diphosphine complexes to catalyze extensive ammonia borane dehydrogenation, releasing greater than two equiv. of hydrogen (H2). Initially believed to be a frontrunner as a high energy density H2 storage medium, AB is a Lewis acid/base adduct that features both hydridic B–H bond and protic N–H bonds. As a highly reactive molecule, the controlled dehydrogenation of AB, accessing ≥ 2 of the 3 stored equiv. of H2, is uncommon. We disclose a catalytic system, utilizing an earth-abundant metal, that is capable of such reactivity. The mechanism by which the catalysis proceeds is dependent on the oxidation state of the precatalyst, with MoII proceeding through a II/IV cycle and Mo0 proceeding through a 0/II cycle. Several Mo hydride complexes were characterized in conjunction with this work. Importantly, the ability of the para-terphenyl diphosphine ancillary ligand to support a range of Mo oxidation states and coordination numbers was established, a feature that provides a foundation for the work presented in subsequent chapters. In Chapter 3, new features of the para-terphenyl diphosphine ligand were discovered, namely facilitation of electron loading that subsequently leads to small molecule functionalization and cleavage. From the Mo dicarbonyl complex described in Chapter 2, stepwise reduction affords Mo0, Mo-II, and Mo-III compounds, all of which were characterized both structurally and by a variety of spectroscopies. The latter two complexes were demonstrated to react with silyl electrophiles, instigating deoxygenative reductive coupling of the bound CO ligands to a metal-free C2O1 fragment. This remarkable four-electron process was studied in detail, characterizing twelve different reaction intermediates, including rare examples of bis(siloxy)carbyne, terminal carbide, and mixed dicarbyne motifs. The cleavage of a bound carbon monoxide (CO), subsequent coupling, and spontaneous product release was an unprecendented sequence of chemical transformations, the detailed mechanistic study of which provides valuable precedent for catalyses for the conversion of C1 oxygenates to multicarbon products. Chapter 4 discusses continuations of this work in an attempt to model Fischer-Tropsch catalysis with higher fidelity. To this end, the silyl electrophiles used in the fundamental studies in Chapter 3 needed to be replaced with protons. Addition of protons to the super-reduced Mo complexes resulted in formal arene hydrogenation; no evidence for C–O functionalization was obtained. These diene-linked complexes; however, provided an opportunity to explore how the nature of the basal π-system effects CO catenation chemistry and ultimately led to the preparation of a Mo-bound C3O3 unit derived entirely from CO. Reactivity with protons was likewise explored for downstream intermediates. Carbide protonation yields a stable methylidyne carbonyl complex, that, upon treatment with hydride, forms a methylidene. Comparison to a silyl-bearing model system suggests that subsequent carbene carbonylation affords enthenone. Chapter 5 and 6 focus on the synthesis and reactivity of Mo(IV) terminal pnictogen complexes isoelectronic to the carbyne and carbide complexes prepared in Chapters 3 and 4. Chapter 5 describes successful N–C bond formation through N– transfer to CO from a MoII anionic nitride precursor. In Chapter 6, the first example of a terminal transition metal phosphide with d-electrons was prepared via a 4 e– oxidative group transfer. This species can undergo a single-electron oxidation, providing, at low temperatures, an unstable Mo(V) phosphide cation that studied extensively by CW and pulse EPR techniques. Upon warming, P–P bond formation is evidenced by chemical trapping and characterization of coupling byproducts. Related phosphinidene (Mo=PR), phosphide (Mo-PR2), and dinuclear μ-phosphido compounds are also reported. In a collaboration with Mr. Yohei Ueda and Dr. Masa Hirahara these complexes were explored for proton reduction reactivity. Isotopic labeling suggests formation of a dinuclear μ-phosphinidene upon treatment with acid, and a bimetallic hydride μ-phosphide was accessed from reaction with hydride. The final chapters of this dissertation are focused on the reduction of carbon dioxide (CO2). Chapter 7 presents a fundamental study involving Lewis acid (LA) aditives, that demonstrates the importance of kinetic stabilization, and not just thermodynamic activation, in productive small molecule functionalization chemistry. Upon addition of LAs, well-defined adducts are formed with Mo-bound CO2. Protonation results in C–O bond cleavage, utilizing two electrons from the metal center to reduce CO2 to CO and H2O. Though the degree of CO2 activation trends well as a function of Lewis acidity, the residence time of the bound CO2, reported via the rate of CO2 self-exchange, is shown to correlate to the degree of C–O scission. Chapter 8 looks at CO2 reactivity with E–H bonds, describing first stoichiometric reactivity with silanes. In this system, CO2 is reduced to CO and silanol; mechanistic studies suggest a pathway that involves oxygen atom transfer to silane from a transient Mo oxo. In a collaboration with Dr. Naoki Shida, CO2 hydrogenation was explored, with demonstration of bidirectional catalysis in addition to detailed studies investigating the elementary steps of both formate formation and formic acid dehydrogenation.</p

The Unspace Case: Developing a Maker Movement in a Multipurpose, Flexible Space, Library Setting

This paper presents the ongoing design, development, and implementation of a K-16 maker movement centered around a joint public school/university library whose minimal dedicated space has expanded opportunities for public participation, partnerships, and shared resources. As the library sought to circulate STEM resources for K-9 teachers and students in 2011, University instructors were seeking opportunities for preservice teachers to interact meaningfully with authentic, technology-rich environments. These separate endeavors coalesced over time to form a robust community of various school, university, and public stakeholders focused on mathematics and science learning. Because the space was not bound to a single physical location, proponents were able to leverage various resources, mobile tools, and settings to explore and apply STEM knowledge, construct products, and attract new and returning users. This design case articulates how the maker movement provides curricular programming while maintaining a playful atmosphere that encourages personal exploration regardless of age and ability

RESGATE VEGETATIVO POR SEMIANELAMENTO E ESTAQUIA DE ÁRVORES ADULTAS DE IMBUIA (Ocotea porosa) VEGETATIVE RESCUE BY HALF-ANNEALING AND CUTTING IN ADULT TREES OF Ocotea porosa

O objetivo foi avaliar o método de resgate vegetativo por semianelamento a 30 e 60 cm do solo de árvores adultas de Imbuia e o potencial de enraizamento das estacas provenientes das brotações. Para este experimento foram utilizadas 10 árvores. As estacas oriundas das brotações emitidas receberam ácido indolbutírico (AIB) nas concentrações de 0, 3.000 e 6.000 mg.L-1. Com probabilidade de 5%, não foi observada diferença estatística entre as alturas de semianelamento. As estacas que receberam AIB de 3.000 mg.L-1 apresentaram melhor desempenho na emissão de brotos. Nenhuma estaca enraizou no período de 80 dias

RESGATE VEGETATIVO POR SEMIANELAMENTO E ESTAQUIA DE ÁRVORES ADULTAS DE IMBUIA (Ocotea porosa)

O objetivo foi avaliar o método de resgate vegetativo por semianelamento a 30 e 60 cm do solo de árvores adultas de Imbuia e o potencial de enraizamento das estacas provenientes das brotações. Para este experimento foram utilizadas 10 árvores. As estacas oriundas das brotações emitidas receberam ácido indolbutírico (AIB) nas concentrações de 0, 3.000 e 6.000 mg.L-1. Com probabilidade de 5%, não foi observada diferença estatística entre as alturas de semianelamento. As estacas que receberam AIB de 3.000 mg.L-1 apresentaram melhor desempenho na emissão de brotos. Nenhuma estaca enraizou no período de 80 dias

Genomic structural variations lead to dysregulation of important coding and non-coding RNA species in dilated cardiomyopathy

The transcriptome needs to be tightly regulated by mechanisms that include transcription factors, enhancers, and repressors as well as non-coding RNAs. Besides this dynamic regulation, a large part of phenotypic variability of eukaryotes is expressed through changes in gene transcription caused by genetic variation. In this study, we evaluate genome-wide structural genomic variants (SVs) and their association with gene expression in the human heart. We detected 3,898 individual SVs affecting all classes of gene transcripts (e.g., mRNA, miRNA, lncRNA) and regulatory genomic regions (e.g., enhancer or TFBS). In a cohort of patients (n = 50) with dilated cardiomyopathy (DCM), 80,635 non-protein-coding elements of the genome are deleted or duplicated by SVs, containing 3,758 long non-coding RNAs and 1,756 protein-coding transcripts. 65.3% of the SV-eQTLs do not harbor a significant SNV-eQTL, and for the regions with both classes of association, we find similar effect sizes. In case of deleted protein-coding exons, we find downregulation of the associated transcripts, duplication events, however, do not show significant changes over all events. In summary, we are first to describe the genomic variability associated with SVs in heart failure due to DCM and dissect their impact on the transcriptome. Overall, SVs explain up to 7.5% of the variation of cardiac gene expression, underlining the importance to study human myocardial gene expression in the context of the individual genome. This has immediate implications for studies on basic mechanisms of cardiac maladaptation, biomarkers, and (gene) therapeutic studies alike

Progressive skin fibrosis is associated with a decline in lung function and worse survival in patients with diffuse cutaneous systemic sclerosis in the European Scleroderma Trials and Research (EUSTAR) cohort.

Objectives To determine whether progressive skin fibrosis is associated with visceral organ progression and mortality during follow-up in patients with diffuse cutaneous systemic sclerosis (dcSSc). Methods We evaluated patients from the European Scleroderma Trials and Research database with dcSSc, baseline modified Rodnan skin score (mRSS) ≥7, valid mRSS at 12±3 months after baseline and ≥1 annual follow-up visit. Progressive skin fibrosis was defined as an increase in mRSS &gt;5 and ≥25% from baseline to 12±3 months. Outcomes were pulmonary, cardiovascular and renal progression, and all-cause death. Associations between skin progression and outcomes were evaluated by Kaplan-Meier survival analysis and multivariable Cox regression. Results Of 1021 included patients, 78 (7.6%) had progressive skin fibrosis (skin progressors). Median follow-up was 3.4 years. Survival analyses indicated that skin progressors had a significantly higher probability of FVC decline ≥10% (53.6% vs 34.4%; p&lt;0.001) and all-cause death (15.4% vs 7.3%; p=0.003) than non-progressors. These significant associations were also found in subgroup analyses of patients with either low baseline mRSS (≤22/51) or short disease duration (≤15 months). In multivariable analyses, skin progression within 1 year was independently associated with FVC decline ≥10% (HR 1.79, 95% CI 1.20 to 2.65) and all-cause death (HR 2.58, 95% CI 1.31 to 5.09). Conclusions Progressive skin fibrosis within 1 year is associated with decline in lung function and worse survival in dcSSc during follow-up. These results confirm mRSS as a surrogate marker in dcSSc, which will be helpful for cohort enrichment in future trials and risk stratification in clinical practice