41 research outputs found
Farmers as experts: interpreting the "hidden" messages of participatory video across African contexts
Recent scholarship has contributed important insights into the political dynamics inherent in the process of making and showing participatory videos (PV). As a research method and an instrument for social change, participatory video has both potential and limitations for overturning the power dynamics embedded within research and in development processes. This paper focuses on experiences of incorporating participatory video in land management projects in four countries in Africa. Along with other participatory methods, the videos represented an effort to include community perspectives and objectives into the research process. Analysis of PV has largely focused on examining the tensions and contradictions involved in the process of making participatory videos. There has been less focus on the content of the videos themselves and what it might suggest for empowerment, voice and representation. This paper attempts to address this gap by examining the implications of the narratives that emerge in five different videos. On the surface, the participants appear to repeat dominant national and global narratives about land degradation. However, the fact that farmers present themselves as experts on these topics and the ways in which they appropriate and reconfigure the dominant narratives, can be seen as an act of empowerment. In this way, they preclude the need for external intervention on how to manage their resources
Rhenium(I) conjugates as tools for tracking cholesterol in cells
Cholesterol is vital to control membrane integrity and fluidity, but is also a precursor to produce steroid hormones, bile acids, and vitamin D. Consequently, altered cholesterol biology has been linked to many diseases, including metabolic syndromes and cancer. Defining the intracellular pools of cholesterol and its trafficking within cells is essential to understand both normal cell physiology and mechanisms of pathogenesis. We have synthesized a new cholesterol mimic (ReTEGCholestanol), comprising a luminescent rhenium metal complex and a cholestanol targeting unit, linked using a tetraethylene glycol (TEG) spacer. ReTEGCholestanol demonstrated favourable imaging properties and improved water solubility when compared to a cholesterol derivative, and structurally related probes lacking the TEG linker. A non-malignant and three malignant prostate cell lines were used to characterize the uptake and intracellular distribution of ReTEGCholestanol. The ReTEGCholestanol complex was effectively internalized and mainly localized to late endosomes/lysosomes in non-malignant PNT1a cells, while in prostate cancer cells it also accumulated in early endosomes and multivesicular bodies, suggesting disturbed cholesterol biology in the malignant cells. The ReTEGCholestanol is a novel imaging agent for visualizing endosomal uptake and trafficking, which may be used to define cholesterol related biology including membrane integration and altered lipid trafficking/processing
Unprecedented staining of polar lipids by a luminescent rhenium complex revealed by FTIR microspectroscopy in adipocytes.
Fourier transform infrared (FTIR) microspectroscopy and confocal imaging have been used to demonstrate that the neutral rhenium(i) tricarbonyl 1,10-phenanthroline complex bound to 4-cyanophenyltetrazolate as the ancillary ligand is able to localise in regions with high concentrations of polar lipids such as phosphatidylethanolamine (PE), sphingomyelin, sphingosphine and lysophosphatidic acid (LPA) in mammalian adipocytes
Do lambs perceive regular human stroking as pleasant? Behavior and heart rate variability analyses
Stroking by humans is beneficial to the human-animal relationship and improves welfare in many species that express intraspecific allogrooming, but very few studies have looked at species like sheep that do not express such contact except around parturition. This study investigated the way lambs perceive regular human tactile contact using behavioral and physiological responses. Twenty-four lambs were reared and bucket-fed in groups of four. All were stroked daily by their familiar caregiver. At 8 weeks of age, the lambs were individually tested in their home pen but in a 1×1m open-barred pen after a 15h period of habituation to physical separation from peers while remaining in visual and auditory contact. Half of the lambs received stroking by their caregiver for 8min and half were exposed to their caregiver’s immobile presence. Heart rate and heart rate variability were recorded and analyzed by 2-min slots over the same interval based on three measures: mean heart rate value (HR), root mean square of successive differences (RMSSD) and standard deviation of all intervals measured between consecutive sinus beats (SDNN). Behavioral responses (ear postures of the lamb and time spent in contact with the familiar caregiver, on the knees of the familiar caregiver, and moving) were recorded throughout the test. Lamb HR decreased continuously while in the presence of their caregiver. Lambs being stroked showed slower HR and higher RMSSD which reflected positive emotional states compared to lambs left unstroked. All behavioral variables were highly correlated with the main component axis of the PCA analyses: the more the animals stayed in contact with their caregiver, the less they moved and the more their ears were hanging. This first component clearly differentiates lambs being stroked or not. Behavioral and physiological observations support the hypothesis that gentle physical contact with the caregiver is perceived positively by lambs
Impact of group housing of pregnant sows on health
Group housing of sows during gestation is mandatory in the EU since 2013. Compared to housing in individual crates, group housing allows the animals to express normal activity and behavior. The present paper discusses the impact of group housing on health, with emphasis on lameness, aggression and possible spread of infectious diseases. The prevalence of lameness is generally higher in sows housed in group than in sows housed individually. Floor space per sow, group size, pen design and flooring are the main factors of group housing involved in lameness development. Especially floor characteristics are important, and particular attention should be paid to the type, building material and quality of the floor, hygiene and the use of bedding such as straw or rubber mats. Aggression between sows is another critical issue in group housing systems. It occurs predominantly because of competition for access to a limited resource, or to establish a social hierarchy. Key factors to prevent aggression in group housing include gradual familiarization of unfamiliar animals, sufficient space and pen structure during initial mixing, minimizing opportunities for dominant sows to steal food from subordinates, provision of a good quality floor, environmental enrichment and use of straw bedding. Very scarce evidence-based information is available on the relationship between group housing and infectious disease. Compared to individual housing, sows in group housing have more nose-to-nose contact, and they have more oral contact with feces and urine. These factors could contribute to a higher or faster transmission of pathogens, but so far, there is no evidence showing more disease problems in group housing systems. In conclusion, in group housing systems, particular attention should be paid to prevention of lameness and aggression. Management is crucial but also feeding strategies, floor and bedding, and design of housing are very important as relatively minor adjustments may exert major effects on the animals.Peer reviewe
Nanoassembled Capsules as Delivery Vehicles for Large Payloads of High Relaxivity Gd3+ Agents
Nanoassembled capsules (NACs) that incorporate a polymer aggregate inside a silica shell may be loaded with agents that are of particular interest for therapeutic or diagnostic applications. NACs formed using the MRI contrast agent GdDOTP5− in the internal polymer aggregate are reported herein, the smaller of which show promise as potential MRI contrast agents. Unlike many other nanoencapsulated systems, water access to the inner core of these NACs does not appear to be limited and consequently the water relaxivity per Gd3+ agent can reach as high as 24 mM−1 s−1. Robust, spherical capsules were formed using polyallylamine or poly-l-lysine ranging from 0.2 to 5 μm in diameter. The greatest gains in relaxivity were observed for smaller NACs, for which water accessibility remained high but molecular rotation of the Gd3+ chelate was effectively restricted. Larger NACs did not afford such large gains in relaxivity, the result of poorer water accessibility combined with less-effective rotational restriction
Photophysical and biological properties of iridium tetrazolato complexes functionalised with fatty acid chains
Five cyclometalated Ir(III) tetrazolato complexes functionalised with fatty acid chains (octanoic, palmitic, stearic, palmitoleic, and oleic) have been synthesised. The fatty acids were chosen to evaluate the potential effect of the length and degree of unsaturation on the biological properties of the complexes for use as cellular imaging agents. The complexes were analysed in both organic and aqueous media to determine if the presence and nature of the fatty acid chains had a significant effect on their photophysical properties. The complexes display green-yellow emission in dichloromethane solutions with relatively long excited state decays, within the range 360-393 ns, and quantum yields between 5.4% and 6.7% (from degassed solutions). Temperature-dependent photophysical studies suggest that the emitting excited states of the complexes might be quenched by the thermal population of dark states. In water, the quantum yields drop within the range of 0.5%-2.4%, and the photophysical measurements are influenced by the variable degrees of aggregation. In general, the entire series displayed low cytotoxicity and relatively high photostability, which are favourable attributes in the design of cellular imaging agents. Images of live HeLa cells were obtained for all the complexes, but those functionalised with palmitic and stearic acids had limitations due the lower solubility conferred by the saturated aliphatic chains. The complexes were mainly detected within the endoplasmic reticulum
Blackboard Collaborate Ultra: An Online, Interactive Teaching Tool
The last decade has seen a significant increase in the use of online, interactive teaching (Wdonik, 2014) in higher education. This correlates to the increased use of student-centred learning approaches used in higher education (Baeten, Dochy, Struyven, Parmentier, & Vanderbruggen, 2016) including in traditional lectures (Plush & Kehrwald, 2014). The utilisation of online teaching tools has had a significant impact on teaching (Hussein, 2016). These tools are an excellent way of promoting student satisfaction (Li & Pitts, 2009) and, in particular, Millennials’ or digital natives’ desire for interactivity (McCann, Schneiderman, & Hinton, 2010; Prensky, 2001). Management and business educators have also found that online interactive teaching tools have enhanced higher level thinking (Wdowik, 2014), communication and problem-solving competencies (Politis & Politis, 2016)