Studies in the Cyperaceae of Georgia: Distribution of Georgia Sedges, Analysis of the Cyperus squarrosus‐granitophilus Complex & Two New Species

The sedge family (Cyperaceae) is one of the most impactful families to agriculture and a key constituent of graminoid communities in many ecosystems. However, there is no full accounting of all of sedge species vouchered in Georgia. Understanding which sedge taxa occur in the state and where they exist is necessary for both effective pest management and protection of communities and species of interest. I examined holdings at the three largest herbaria in the state to inventory the state's sedge flora. For each taxon, I assessed phenology and the physiographic regions where it occurred. Along with this inventory, I did morphometric analyses of three narrow taxonomic problems. The first analyzed the relationship between the granite outcrop endemic Cyperus granitophilus and its close generalist relative, Cyperus squarrosus. In addition to confirming these species are morphometrically distinct, I discovered a new variety of C. squarrosus which is restricted to granitic uplifts of Texas and Oklahoma. I also investigated two putatively new sedge species from Georgia, one, a Cyperus restricted to exsiccated karst ponds in southwestern Georgia, and, the other, an Eleocharis restricted to high-marshes of Camden County, Georgia. My analysis supports both as distinct species.I. Chapter I – An Annotated Checklist of the Cyperaceae of Georgia Based on the Holdings of the Three Largest Herbaria in the State 1 | Introduction 1 | Materials and Methods 2 | Results 4 | Discussion 4 | References 7 | Tables and Figures 12 | Appendix A: A Checklist of the Cyperaceae of Georgia 28 | Appendix B: Exsiccatae for Checklist 69 | II. Chapter II – A Morphometric analysis of the Cyperus squarrosus-granitophilus Complex in | North America 133 | Introduction 133 | Materials and Methods 134 | Results 136 | Discussion 136 | Taxonomic Treatment and Key 139 | References 142 | Tables and Figures 144 | Appendix A: Vouchers Examined Physically and Digitally 165 | III. Chapter III – A Morphometric Analysis of a Putative New Cyperus from Karst Ponds in Southern Georgia 185 | Introduction 185 | Materials and Methods 185 | Results 186 | Discussion 187 | Taxonomic Treatment and Key 188 | References 190 | Tables and Figures 191 | Appendix A: Additional Vouchers Examined 205 | IV. Chapter IV -- A Morphometric Analysis of a Putative New Eleocharis from the High Marsh of Camden County 212 | Introduction 212 | Materials and Methods 213 | Results 213 | Discussion 214 | Taxonomic Treatment and Key 214 | References 217 | Tables and Figures 218 | Appendix A: Additional Specimens Examined Physically and Digitally 230 |Carter, J. RichardGoddard, RussNelson, GilZomlefer, Wendy B.LaPlant, James T.M.S.Biolog

An enzymatic Finkelstein reaction : fluorinase catalyses direct halogen exchange

We thank the Engineering and Physical Sciences Research Council, UK, for a research grant.The fluorinase enzyme from Streptomyces cattleya is shown to catalyse a direct displacement of bromide and iodide by fluoride ion from 5′-bromodeoxyadenosine (5′-BrDA) and 5′-iododeoxyadenosine (5′-IDA) respectively to form 5′-fluorodeoxyadenosine (5′-FDA) in the absence of L-methionine (L-Met) or S-adenosyl-L-methionine (SAM). 5′-BrDA is the most efficient substrate for this enzyme catalysed Finkelstein reaction.PostprintPeer reviewe

Pulsed laser illumination of photovoltaic cells

In future space missions, free electron lasers (FEL) may be used to illuminate photovoltaic receivers to provide remote power. Both the radio-frequency (RF) and induction FEL produce pulsed rather than continuous output. In this work we investigate cell response to pulsed laser light which simulates the RF FEL format. The results indicate that if the pulse repetition is high, cell efficiencies are only slightly reduced compared to constant illumination at the same wavelength. The frequency response of the cells is weak, with both voltage and current outputs essentially dc in nature. Comparison with previous experiments indicates that the RF FEL pulse format yields more efficient photovoltaic conversion than does an induction FEL format

Enzymatic radiosynthesis of a 18F-Glu-Ureido-Lys ligand for the prostate-specific membrane antigen (PSMA)

We thank the Engineering and Physical Sciences Research Council, UK, for a research grant (EP/M01262X/1).Peer reviewedPostprin

An engineered E. coli strain for direct in vivo fluorination

This work was funded by the Industrial Biotechnology Innovation Centre (IBioIC) with support from GlaxoSmithKline, and also the EU Horizon 2020 (Sinfonia consortia).Selectively fluorinated compounds are found frequently in pharmaceutical and agrochemical products where currently 25–30 % of optimised compounds emerge from development containing at least one fluorine atom. There are many methods for the site‐specific introduction of fluorine, but all are chemical and they often use environmentally challenging reagents. Biochemical processes for C−F bond formation are attractive, but they are extremely rare. In this work, the fluorinase enzyme, originally identified from the actinomycete bacterium Streptomyces cattleya, is engineered into Escherichia coli in such a manner that the organism is able to produce 5′‐fluorodeoxyadenosine (5′‐FDA) from S‐adenosyl‐l‐methionine (SAM) and fluoride in live E. coli cells. Success required the introduction of a SAM transporter and deletion of the endogenous fluoride efflux capacity in order to generate an E. coli host that has the potential for future engineering of more elaborate fluorometabolites.PostprintPeer reviewe

Mild bleeding disorders::what every clinician should know

Patients with mild bleeding disorders are under-recognized and frequently present to general physicians. The underlying reasons for bleeding are multifactorial. There is little evidence to guide diagnostic and management decision making in patients with mild bleeding disorders. This article outlines different types of mild bleeding disorders, with a particular focus on bleeding associated with low levels of von Willebrand factor and mild platelet defects. It gives practical, evidence-based advice on the investigation and management of patients with a suspected or known mild bleeding disorder, considering the scenarios of an acute bleed, stable outpatient, peri-surgical management and thrombosis. Patients with a mild bleeding disorder have variable bleeding because of the interplay of genetic and environmental factors. The clinical history remains of utmost importance in their general management. Liaison with a specialist centre, multidisciplinary assessment and a careful judgement of the balance of risk in each individual circumstance is required to safely manage these patients. </jats:p

What Angles Can Tell Us About What Holes Are Not

In this paper I argue that holes are not objects, but should instead be construed as properties or relations. The argument proceeds by first establishing a claim about angles: that angles are not objects, but properties or relations. It is then argued that holes and angles belong to the same category, on the grounds that they share distinctive existence and identity conditions. This provides an argument in favour of categorizing holes as one categorizes angles. I then argue that a commitment to the existence of properties to be identified with holes provides sufficient resources to account for true claims about holes. © 2011 Springer Science+Business Media B.V

Empirical Models of Transitions between Coral Reef States: Effects of Region, Protection, and Environmental Change

There has been substantial recent change in coral reef communities. To date, most analyses have focussed on static patterns or changes in single variables such as coral cover. However, little is known about how community-level changes occur at large spatial scales. Here, we develop Markov models of annual changes in coral and macroalgal cover in the Caribbean and Great Barrier Reef (GBR) regions

Oligomerization engineering of the fluorinase enzyme leads to an active trimer that supports synthesis of fluorometabolites in vitro

This work was funded by The Novo Nordisk Foundation grant to the Center for Biosustainability (NNF10CC1016517). P.I.N. was funded by grants from The Novo Nordisk Foundation (NNF20CC0035580, and LiFe, NNF18OC0034818), the European Union’s Horizon 2020 Research and Innovation Programme under grant agreement No. 814418 (SinFonia) and the Danish Council for Independent Research (SWEET, DFF-Research Project 8021-00039B). T.K. and M.N.D. were funded by fellowships from the European Union's Horizon 2020 research and innovation program under a Marie Skłodowska Curie project under grant agreement No. 713683 (COFUNDfellowsDTU).The fluorinase enzyme represents the only biological mechanism capable of forming stable C–F bonds characterized in nature thus far, offering a biotechnological route to the biosynthesis of value-added organofluorines. The fluorinase is known to operate in a hexameric form, but the consequence(s) of the oligomerization status on the enzyme activity and its catalytic properties remain largely unknown. In this work, this aspect was explored by rationally engineering trimeric fluorinase variants that retained the same catalytic rate as the wild-type enzyme. These results ruled out hexamerization as a requisite for the fluorination activity. The Michaelis constant (KM) for S-adenosyl-l-methionine, one of the substrates of the fluorinase, increased by two orders of magnitude upon hexamer disruption. Such a shift in S-adenosyl-l-methionine affinity points to a long-range effect of hexamerization on substrate binding – likely decreasing substrate dissociation and release from the active site. A practical application of trimeric fluorinase is illustrated by establishing in vitro fluorometabolite synthesis in a bacterial cell-free system.Publisher PDFPeer reviewe

InGaAs PV Device Development for TPV Power Systems

Indium gallium arsenide (InGaAs) photovoltaic devices have been fabricated with bandgaps ranging from 0.75 eV to 0.60 eV on Indium Phosphide (InP) substrates. Reported efficiencies have been as high as 11.2 percent (AMO) for the lattice matched 0.75 eV devices. The 0.75 eV cell demonstrated 14.8 percent efficiency under a 1500 K blackbody with a projected efficiency of 29.3 percent. The lattice mismatched devices (0.66 and 0.60 eV) demonstrated measured efficiencies of 8 percent and 6 percent respectively under similar conditions. Low long wavelength response and high dark currents are responsible for the poor performance of the mismatched devices. Temperature coefficients have been measured and are presented for all of the bandgaps tested