Science Education for Citizenship and a Sustainable Future

In this article Jerry Wellington argues very strongly in favour of the role of science in citizenship education. He emphasizes the need for knowledge, skills and action and suggests areas and ways in which pupils can be engaged in the struggle for a sustainable future where interdependence and interconnectedness mesh well with notions of equity and justice

An appraisal of housing satisfaction in South Africa low income housing scheme

Abstract: Post-occupancy evaluation techniques have been developed to provide a means for evaluating occupant responses to changes in an environment and linking this response to physical measures of that environment. POE has been used to evaluate the performance of buildings after they have been built and occupied for some time. This paper presents findings on the social and physical factors which influence residential satisfaction in four different government Housing Subsidy locations in the Gauteng Province of South Africa. Data obtained from the occupant survey were analyzed through the use of descriptive statistics. Findings arising from the survey revealed that the respondents were satisfied with their overall housing situation, but had complaints about certain aspects of the housing unit. However, the respondents informed that most of their housing needs were not being met. Also, a comparison is also made of the perceived factors of dissatisfaction amongst the housing subsidy occupants. It is recommended that a wider systematic coverage of the subject through investigation and diagnostic POE and occupants’ need assessment should be carried out in housing subsidy schemes in South Africa

modCHIMERA: A novel murine closed-head model of moderate traumatic brain injury

AbstractTraumatic brain injury is a major source of global disability and mortality. Preclinical TBI models are a crucial component of therapeutic investigation. We report a tunable, monitored model of murine non-surgical, diffuse closed-head injury—modCHIMERA—characterized by impact as well as linear and rotational acceleration. modCHIMERA is based on the Closed-Head Impact Model of Engineered Rotational Acceleration (CHIMERA) platform. We tested this model at 2 energy levels: 1.7 and 2.1 Joules—substantially higher than previously reported for this system. Kinematic analysis demonstrated linear acceleration exceeding injury thresholds in humans, although outcome metrics tracked impact energy more closely than kinematic parameters. Acute severity metrics were consistent with a complicated-mild or moderate TBI, a clinical population characterized by high morbidity but potentially reversible pathology. Axonal injury was multifocal and bilateral, neuronal death was detected in the hippocampus, and microglial neuroinflammation was prominent. Acute functional analysis revealed prolonged post-injury unconsciousness, and decreased spontaneous behavior and stimulated neurological scores. Neurobehavioral deficits were demonstrated in spatial learning/memory and socialization at 1-month. The overall injury profile of modCHIMERA corresponds with the range responsible for a substantial portion of TBI-related disability in humans. modCHIMERA should provide a reliable platform for efficient analysis of TBI pathophysiology and testing of treatment modalities.</jats:p

Metabolic modeling and analysis of the metabolic switch in Streptomyces coelicolor

Background The transition from exponential to stationary phase in Streptomyces coelicolor is accompanied by a major metabolic switch and results in a strong activation of secondary metabolism. Here we have explored the underlying reorganization of the metabolome by combining computational predictions based on constraint-based modeling and detailed transcriptomics time course observations. Results We reconstructed the stoichiometric matrix of S. coelicolor, including the major antibiotic biosynthesis pathways, and performed flux balance analysis to predict flux changes that occur when the cell switches from biomass to antibiotic production. We defined the model input based on observed fermenter culture data and used a dynamically varying objective function to represent the metabolic switch. The predicted fluxes of many genes show highly significant correlation to the time series of the corresponding gene expression data. Individual mispredictions identify novel links between antibiotic production and primary metabolism. Conclusion Our results show the usefulness of constraint-based modeling for providing a detailed interpretation of time course gene expression data

Large Dust Aerosol Sizes Seen During the 2018 Martian Global Dust Event by the Curiosity Rover

Mars’ atmosphere typically supports dust aerosol with an effective radius near 1.5 μm, varying from ~1 μm during low dust times near northern summer solstice to ~2 μm during higher dust times in southern spring and summer. After global dust events, size variations outside this range have not previously been observed. We report on imaging and spectral observations by the Curiosity rover through the 2018 global dust event. These observations show that the dust effective radius was seasonally normal prior to the local onset of increased opacity, increased rapidly above 4 μm with increasing opacity, remained above 3 μm over a period of ~50 Martian solar days, then returned to seasonal values before the opacity did so. This demonstrates lifting and regionalâ scale transport of a dust population ~3 times the size of typical dust aerosol.Plain Language SummaryDuring the global dust storm of 2018, the Curiosity rover measured the variation of atmospheric dust over time. During the onset of the dust storm, typical Martian dust was enhanced by much larger particles that were freshly lifted off the surface in distant storms and then carried to the rover site at Gale crater. The larger dust particles persisted for weeks, but fell out of the atmosphere faster than the typical dust as normal conditions were restored.Key PointsThe Curiosity rover observed dust aerosol size variations through the 2018 global dust eventThe average dust radius increased above 4 μm, more than double the largest sizes previously seen with Curiosity’s instrumentsThe observations demonstrate the lifting and regionalâ scale transport of dust significantly larger than typical dust aerosolPeer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/151856/1/grl59493.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/151856/2/grl59493_am.pd

Mineral Composition of \u3cem\u3eBrachiaria brizantha\u3c/em\u3e cv. MG5 Irrigated and Non-Irrigated Subjected to Grazing

Brachiaria brizantha cv. MG5 is an important component of pastures in Brazil. Past studies (Corsi and Marta Jr. (1998), Maya (2003)) have shown significant pasture and animal production increases can be obtained through irrigation and associated grazing management. Such systems can significantly increase economic viability of production systems based on these pastures (Cedeño 2003). However, past studies have not measured possible differences in mineral composition of such pastures throughout the year with and without irrigation. Such differences, if present, may have implication for animal productivity. This study had the objective of evaluating the mineral composition of Brachiaria brizantha cv. MG5 with and without irrigation in different times of the year

Effects of Irrigation and Season on Performance of Grazed Pastures of \u3cem\u3eBrachiaria brizantha\u3c/em\u3e cv. MG5

In Brazil, livestock production is based primarily on systems with continuously grazed natural or cultivated pastures (FAO 2009). Intensifying animal breeding, handling and knowledge strategies is necessary to obtain improvements in production indices for economically feasible and sustainable grazing systems (Cedeño et al. 2003). Beef cattle breeding on irrigated pasture, like all forms of intensive grazing, requires the use of forage species with high potential for production and quality, and Brachiaria brizantha cv. MG5 is considered a good option. This study aimed to evaluate the effects of irrigation on the performance of B. brizantha cv. MG5 grazed rotationally by beef cattle at different times of the year