Assessing Feeding Preferences and Spatial Patterns of Lagodon rhomboides Linnaeus

Mesograzers have the ability to greatly mitigate the effects of eutrophication in seagrass systems. In this study we look at pinfish (Lagodon rhomboides Linnaeus) as a potential epiphytic grazer and assess feeding preferences during a transitional stage in the ontogenetic diet shift exhibited by these fish. Since pinfish are abundant in seagrass meadows in the northern Gulf of Mexico, their dietary preferences have the potential to greatly impact seagrasses in this system. Twenty-four hour feeding trials were conducted to determine pinfish preference between seagrass (Thalassia testudinum) and algal epiphytes. St. Joseph Bay, FL was also surveyed to determine areas within this ecosystem that could be highly impacted by pinfish abundance. Significant spatial patterns were found among pinfish, as well as urchins and invertebrates, suggesting that some areas might be experiencing stronger grazing pressures. Feeding trials support previous studies showing that pinfish consume little to no T. testudinum and spatial patterns within St. Joseph Bay support past research showing that S. filliforme is a preferred seagrass for pinfish. Data regarding epiphytes as a preferred food source were inconclusive, as variation was high among treatments; further study is required

Cytological analysis of self-incompatibility in bermudagrass

Agronom

En kvalitativ studie av hvordan relasjonen mellom barneverntjenesten og det afrikanske miljøet kan styrkes

Denne bacheloroppgavens formål er å undersøke hvordan relasjonen mellom barnevernet og det afrikanske miljø kan forbedres. Dette er i forbindelse med barnevernssaker, som er i vurderinger om barnets beste. I flere år har det vært mye diskusjoner om samarbeidet og relasjonen mellom barnevernet og flerkulturelle familier, særlig personer med afrikansk bakgrunn. I media blir det blant annet opplyst at flere flerkulturelle familier opplever frykt og mistillit ovenfor den norske barneverntjenesten (Ylvisaker, Rugkåsa & Hansen-Holm, 2018). Dette kan oftest skyldes ofte manglende informasjon eller feil informasjon om barnevernet, negative rykter om barnevernet i deres nærmiljø. Det har tidligere vært flere afrikanske foreldre som har uttrykt at de opplever fordømmelse og stigma på bakgrunn av deres etnisitet. Samtidig som de opplever at de må skape gode inntrykk i både skoler og barnehage, med bakgrunn av redsel for å motta bekymring. Det har også blitt belyst at afrikanske mødre opplever at det utfordrende å forholde seg til det norske regelverket Problemstillingen for denne bacheloroppgaven er: Hvordan relasjonen mellom barneverntjenesten og det afrikanske miljø kan styrkes? Studiens datamateriale er basert på semi-strukturerte intervjuer. For å utforske oppgavens problemstilling rekrutterte jeg 5 informanter. Informantene bestod av tre personer som har vært i kontakt med barneverntjenesten og som har afrikansk opprinnelse. Videre bestod informantene av en minoritetskonsulent og en barnevernskonsulent. Informantene ble rekruttert gjennom Facebook, og intervjuet ble holdt på Zoom. For å få et større innblikk og forståelse av informantens erfaring har jeg brukt individuelle intervjuer for å samle inn data. Dette er slik at informantene får en større mulighet til å uttale seg om deres personlige meninger, erfaringer og opplevelser. Gjennom intervjuene uttrykte informanten sine forventninger og utfordringer til hvordan samarbeidet og relasjonen mellom barnevernet og barneverntjenesten kan styrkes. I drøftingen har jeg drøftet informantenes besvarelser i lys av teorien, som har blitt brukt i denne oppgaven. Denne oppgaven har vært en spennende og lærerik prosess. Jeg håper videre at denne bacheloroppgaven kan bidra til å gi en større innsikt om hvordan relasjonen mellom barnevernet og det afrikanske miljø kan styrkes.The purpose of this bachelor thesis is to investigate how the relationship between child welfare and the African society can be improved. This is in connection with child welfare cases, which are in assessments of the child's best interests. For several years, there have been many discussions about the cooperation and relationship between the child welfare service and multicultural families, especially people with an African background. Among other things, the media reports that several multicultural families experience fear and mistrust of the Norwegian child welfare service (Ylvisaker, Rugkåsa & Hansen-Holm, 2018). This can most often be due to lack of information or incorrect information about the child welfare service, negative rumors about the child welfare service in their immediate environment. There have previously been several African parents who have expressed that they experience condemnation and stigma on the basis of their ethnicity. At the same time, they experience that they must create good impressions in both schools and kindergartens, based on fear of receiving concern. It has also been highlighted that African mothers find it challenging to comply with Norwegian regulations The topic for this bachelor thesis is: How can the relationship between the child welfare service and the African society be strengthened? The data material is based on semi-structured interviews. To explore the topic of the thesis, I recruited 5 informants. The informants consisted of three people who have been in contact with the child welfare service and who are of African origin. Furthermore, the informants consisted of a minority consultant and a child welfare consultant. The informants were recruited through Facebook, and the interview was held at Zoom. To gain a greater insight and understanding of the informant's experience, I have used individual interviews to collect data. This is so that the informants have a greater opportunity to express themselves about their personal opinions and experiences. Through the interviews, the informant expressed their expectations and challenges to how the cooperation and relationship between the child welfare service can be strengthened. In the discussion, I have discussed the informants' answers in light of the theory, which has been used in this thesis. This bachelor thesis has been exciting and an educational process. I hope this bachelor thesis can help to provide a greater insight into how the relationship between child welfare and the African society can be strengthened

Decolonising Fire: Recognition justice and Aboriginal fire knowledge in the 2019-2020 Australian bushfire news narrative

Australia’s 2019-2020 summer bushfires brought to light two key conversations during its news coverage: the need for better forms of bushfire management, and most importantly, the revival of Aboriginal cultural burning practices. The Australian landscape was formed through fire, and for more than 60,000 years, Aboriginal people across the continent have developed knowledge of the land through generations of custodianship and culture. Despite the ecological and scientific value of Aboriginal place-specific knowledge that has developed alongside the changes of this continent's vast ecosystems, the establishment of the settler-colonial system has deemed this knowledge invalid and unscientific. Drawing on the concepts of decolonisation, misrecognition, epistemic violence, Aboriginal academic literature, and recognition as a component of justice especially, this thesis challenges covert themes of settler-colonialism present in the bushfire news narrative, and will showcase why recognition justice must underscore discussions and initiatives concerning cultural burning. Through a thematic content analysis of news articles published prior, during, and after the bushfires, the findings of this study will highlight how Aboriginal people and their knowledge are still undermined in the media, and on a macrocosmic level, Australia as a colonial institution

Using geospatial analytics to find prospective locations for water harvesting in Northern Ghana

Undergraduate thesis submitted to the Department of Computer Science, Ashesi University, in partial fulfillment of Bachelor of Science degree in Computer Science, May 2020Access to potable water is a difficulty for about a quarter of the world’s population. The people living in the northern regions of Ghana, which have arid to semi-arid vegetation cover, form a significantly large percentage of that number in Ghana. Rainwater harvesting has been found to be an appropriate measure to mitigate the effects of water shortages, but its practice has also been fraught with various challenges. Advancing technology has encouraged much research into the best ways to optimise water catchment and distribution in Ghana, but little documented evidence exists on the application of Geographic Information Systems and Remote Sensing. This study investigates the potential of geospatial analytics in selecting suitable locations to channel resources for optimised rainwater harvesting. Adopting a Multi-Criteria Overlay Analysis model, suitability maps were created to be used as a visualisation tool for the classification of places as suitable or not.Ashesi Universit

Reactivation from the Ni-B state in [NiFe] hydrogenase of Ralstonia eutropha is controlled by reduction of the superoxidised proximal cluster

The tolerance towards oxic conditions of O2-tolerant [NiFe] hydrogenases has been attributed to an unusual [4Fe–3S] cluster that lies proximal to the [NiFe] active site. Upon exposure to oxygen, this cluster converts to a superoxidised (5+) state, which is believed to secure the formation of the so-called Ni–B state that is rapidly reactivated under reducing conditions. Here, the reductive reactivation of the membrane-bound [NiFe]-hydrogenase (MBH) from Ralstonia eutropha in a native-like lipid membrane was characterised and compared to a variant that instead carries a typical [4Fe–4S] proximal cluster. Reactivation from the Ni–B state was faster in the [4Fe–4S] variant, suggesting that the reactivation rate in MBH is limited by the reduction of the superoxidised [4Fe–3S] cluster. We propose that the [4Fe–3S] cluster plays a major role in protecting MBH by blocking the reversal of electron transfer to the [NiFe] active site, which would produce damaging radical oxygen species

How the oxygen tolerance of a [NiFe]-hydrogenase depends on quaternary structure

‘Oxygen-tolerant’ [NiFe]-hydrogenases can catalyze H(2) oxidation under aerobic conditions, avoiding oxygenation and destruction of the active site. In one mechanism accounting for this special property, membrane-bound [NiFe]-hydrogenases accommodate a pool of electrons that allows an O(2) molecule attacking the active site to be converted rapidly to harmless water. An important advantage may stem from having a dimeric or higher-order quaternary structure in which the electron-transfer relay chain of one partner is electronically coupled to that in the other. Hydrogenase-1 from E. coli has a dimeric structure in which the distal [4Fe-4S] clusters in each monomer are located approximately 12 Å apart, a distance conducive to fast electron tunneling. Such an arrangement can ensure that electrons from H(2) oxidation released at the active site of one partner are immediately transferred to its counterpart when an O(2) molecule attacks. This paper addresses the role of long-range, inter-domain electron transfer in the mechanism of O(2)-tolerance by comparing the properties of monomeric and dimeric forms of Hydrogenase-1. The results reveal a further interesting advantage that quaternary structure affords to proteins

Probing intermediates in the activation cycle of [NiFe] hydrogenase by infrared spectroscopy: the Ni-SIr state and its light sensitivity

The [NiFe] hydrogenase from the sulphate-reducing bacterium Desulfovibrio vulgaris Miyazaki F is reversibly inhibited in the presence of molecular oxygen. A key intermediate in the reactivation process, Ni-SIr, provides the link between fully oxidized (Ni-A, Ni-B) and active (Ni-SIa, Ni-C and Ni-R) forms of hydrogenase. In this work Ni-SIr was found to be light-sensitive (T ≤ 110 K), similar to the active Ni-C and the CO-inhibited states. Transition to the final photoproduct state (Ni-SL) was shown to involve an additional transient light-induced state (Ni-SI1961). Rapid scan kinetic infrared measurements provided activation energies for the transition from Ni-SL to Ni-SIr in protonated as well as in deuterated samples. The inhibitor CO was found not to react with the active site of the Ni-SL state. The wavelength dependence of the Ni-SIr photoconversion was examined in the range between 410 and 680 nm. Light-induced effects were associated with a nickel-centred electronic transition, possibly involving a change in the spin state of nickel (Ni2+). In addition, at T ≤ 40 K the CN− stretching vibrations of Ni-SL were found to be dependent on the colour of the monochromatic light used to irradiate the species, suggesting a change in the interaction of the hydrogen-bonding network of the surrounding amino acids. A possible mechanism for the photochemical process, involving displacement of the oxygen-based ligand, is discussed

Suppression of the Nrf2-Dependent Antioxidant Response by Glucocorticoids and 11β-HSD1-Mediated Glucocorticoid Activation in Hepatic Cells

Nuclear factor (erythroid-derived 2)-like 2 (Nrf2) is a key transcription factor regulating a plethora of detoxifying enzymes and antioxidant genes involved in drug metabolism and defence against oxidative stress. The glucocorticoid receptor (GR) is a ligand-induced transcription factor involved in the regulation of energy supply for metabolic needs to cope with various stressors. GR activity is controlled by glucocorticoids, which are synthesized in the adrenal glands and regenerated mainly in the liver from inactive cortisone by 11β-hydroxysteroid dehydrogenase-1 (11β-HSD1).; Using transfected HEK-293 cells and hepatic H4IIE cells we show that glucocorticoids, activated by 11β-HSD1 and acting through GR, suppress the Nrf2-dependent antioxidant response. The expression of the marker genes NQO1, HMOX1 and GST2A was suppressed upon treatment of 11β-HSD1 expressing cells with cortisone, an effect that was reversed by 11β-HSD1 inhibitors. Furthermore, our results demonstrate that elevated glucocorticoids lowered the ability of cells to detoxify H(2)O(2). Moreover, a comparison of gene expression in male and female rats revealed an opposite sexual dimorphism with an inverse relationship between 11β-HSD1 and Nrf2 target gene expression.; The results demonstrate a suppression of the cellular antioxidant defence capacity by glucocorticoids and suggest that elevated 11β-HSD1 activity may lead to impaired Nrf2-dependent antioxidant response. The gender-specific differences in hepatic expression levels of 11β-HSD1 and Nrf2 target genes and the impact of pharmacological inhibition of 11β-HSD1 on improving cellular capacity to cope with oxidative stress warrants further studies in vivo

Electrochemical insights into the mechanism of NiFe membrane-bound hydrogenases

Hydrogenases are enzymes of great biotechnological relevance because they catalyse the interconversion of H2, water (protons) and electricity using non-precious metal catalytic active sites. Electrochemical studies into the reactivity of NiFe membrane-bound hydrogenases (MBH) have provided a particularly detailed insight into the reactivity and mechanism of this group of enzymes. Significantly, the control centre for enabling O2 tolerance has been revealed as the electron-transfer relay of FeS clusters, rather than the NiFe bimetallic active site. The present review paper will discuss how electrochemistry results have complemented those obtained from structural and spectroscopic studies, to present a complete picture of our current understanding of NiFe MBH