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South Africa currently has 90 million cellphone connections and 4G bandwidth is accessible to 75% of the population. Audio-visual media, such as videos, can be used to enhance teaching as the use of multimedia is a key component of blended learning. In total, 92 fourth-year university education students were surveyed to determine their response to video-based assessments. Of the students surveyed, 92% believed that videos assisted their understanding of the course content, 78.5% believed that video-based assessments were less difficult than traditional assessments and 89% intend using audio-visual media in their own classrooms. Significantly, 88.7% believe that such media should be used at least once a week. In addition, once they graduate, 63% of participants intend using social media platforms to communicate with learners. The study suggests that a greater emphasis needs to be placed on blended learning, both in schools and tertiary institutions in South Africa.

Brett, M.R., 2021. How important is coastal tourism for island nations? An assessment of African and Indian Ocean islands. Journal of Coastal Research, 37(3), 568–575. Coconut Creek (Florida), ISSN 0749-0208. Coastal tourism is an important component of the global tourism industry, particularly for island nations where the tourism sector often exceeds 40% of gross domestic product. For African island and Indian Ocean island nations, the tourism sector's economic contribution has not received as much attention. This paper analyses the economic contribution of tourism to the economies of African island nations and analyzes tourism statistics from the World Travel and Tourism Council annual reports. Tourism is a major economic factor for the island nations and is concentrated in the coastal zone. The data indicates that islands with larger and more diversified economies performed better in terms of tourism receipts than did islands with less developed economies. The results show that the average per capita income on the islands is more than six-fold greater than the average for the African continent. To test the importance of the coastal zone, tourist infrastructure was mapped on two African island nations, Mauritius and the Seychelles. Given the predominance of tourist infrastructure in the coastal zone, and the importance of tourism to the economies of many of the African island nations, a rise in sea-level even of 0.5 to 1 meters poses a serious threat to the existence of these island nations.

“Freedom in a commons brings ruin to all.” So argued ecologist Garrett Hardin in “ The Tragedy of the Commons ” in the 13 December 1968 issue of Science ( 1 ). Hardin questioned society's ability to manage shared resources and avoid an environmentally and socially calamitous free-for-all. In the 50 years since, the essay has influenced discussions ranging from climate change (see page 1217 ) to evolution, from infectious disease to the internet, and has reached far beyond academic literature—but not without criticism. Considerable work, notably by Nobelist Elinor Ostrom ( 2 ), has challenged Hardin, particularly his emphasis on property rights and government regulatory leviathans as solutions. Instead, research has documented contexts, cases, and principles that reflect the ability of groups to collectively govern common resources. To mark this anniversary and celebrate the richness of research and practice around commons and cooperation, Science invited experts to share some contemporary views on such tragedies and how to avert them. — Brad Wible

The links between ethics, medicine and the law cannot readily produce appropriate criteria for human quality questions, largely because ethics are misconstrued where they are not excluded; but also because the science at issue is full of unknowns. The paper surveys issues in eugenics, abortion and euthanasia.

Today, the world's forests are threatened by global warming, growing demand for wood products, and increasing pressure to clear tropical forests for agricultural use. Economic globalization has enabled Western corporations to export timber processing jobs and import cheap wood products from developing countries. Timber plantations of exotic, fast-growing species supply an ever-larger amount of the world's wood. In response, many countries have established forest areas protected from development. In this book, Brett Bennett views today's forestry issues from a historical perspective. The separation of wood production from the protection of forests, he shows, stems from entangled environmental, social, political, and economic factors. This divergence -- driven by the concomitant intensification of production and creation of vast protected areas -- is reshaping forest management systems both public and private. Bennett shows that plantations and protected areas evolved from, and then undermined, an earlier integrated forest management system that sought both to produce timber and to conserve the environment. He describes the development of the science and profession of forestry in eighteenth- and nineteenth-century Europe; discusses the twentieth-century creation of timber plantations in the Americas, Asia, Africa, and Australia; and examines the controversies over deforestation that led to the establishment of protected areas. Bennett argues that the problems associated with the bifurcation of forest management -- including the loss of forestry knowledge necessary to manage large ecosystems for diverse purposes -- suggest that a more integrated model would be preferable.

Background Current heart failure (HF) treatment is based on targeting symptoms and left ventricle dysfunction severity, relying on a common HF pathway paradigm to justify common treatments for HF patients. This common strategy may belie an incomplete understanding of heterogeneous underlying mechanisms and could be a barrier to more precise treatments. We hypothesized we could use RNA-sequencing (RNA-seq) in human heart tissue to delineate HF etiology-specific gene expression signatures. Results RNA-seq from 64 human left ventricular samples: 37 dilated (DCM), 13 ischemic (ICM), and 14 non-failing (NF). Using a multi-analytic approach including covariate adjustment for age and sex, differentially expressed genes (DEGs) were identified characterizing HF and disease-specific expression. Pathway analysis investigated enrichment for biologically relevant pathways and functions. DCM vs NF and ICM vs NF had shared HF-DEGs that were enriched for the fetal gene program and mitochondrial dysfunction. DCM-specific DEGs were enriched for cell-cell and cell-matrix adhesion pathways. ICM-specific DEGs were enriched for cytoskeletal and immune pathway activation. Using the ICM and DCM DEG signatures from our data we were able to correctly classify the phenotypes of 24/31 ICM and 32/36 DCM samples from publicly available replication datasets. Conclusions Our results demonstrate the commonality of mitochondrial dysfunction in end-stage HF but more importantly reveal key etiology-specific signatures. Dysfunctional cell-cell and cell-matrix adhesion signatures typified DCM whereas signals related to immune and fibrotic responses were seen in ICM. These findings suggest that transcriptome signatures may distinguish end-stage heart failure, shedding light on underlying biological differences between ICM and DCM.

Intracellular Na elevation in the heart is a hallmark of pathologies where both acute and chronic metabolic remodelling occurs. Here, we assess whether acute (75 μM ouabain 100 nM blebbistatin) or chronic myocardial Na i load (PLM 3SA mouse) are causally linked to metabolic remodelling and whether the failing heart shares a common Na-mediated metabolic ‘fingerprint’. Control (PLM WT ), transgenic (PLM 3SA ), ouabain-treated and hypertrophied Langendorff-perfused mouse hearts are studied by 23 Na, 31 P, 13 C NMR followed by 1 H-NMR metabolomic profiling. Elevated Na i leads to common adaptive metabolic alterations preceding energetic impairment: a switch from fatty acid to carbohydrate metabolism and changes in steady-state metabolite concentrations (glycolytic, anaplerotic, Krebs cycle intermediates). Inhibition of mitochondrial Na/Ca exchanger by CGP37157 ameliorates the metabolic changes. In silico modelling indicates altered metabolic fluxes (Krebs cycle, fatty acid, carbohydrate, amino acid metabolism). Prevention of Na i overload or inhibition of Na/Ca mito may be a new approach to ameliorate metabolic dysregulation in heart failure. The failing heart is characterised by both alterations in mitochondrial metabolism and an elevation of cytosolic sodium. Here, the authors use 23 Na NMR and metabolic profiling to show these are related, and that elevation in intracellular Na reprograms cardiac substrate utilisation via effects on mitochondrial Na/Ca exchange.

We present an overview of the National Science Foundation’s Daniel K. Inouye Solar Telescope (DKIST), its instruments, and support facilities. The 4 m aperture DKIST provides the highest-resolution observations of the Sun ever achieved. The large aperture of DKIST combined with state-of-the-art instrumentation provide the sensitivity to measure the vector magnetic field in the chromosphere and in the faint corona, i.e. for the first time with DKIST we will be able to measure and study the most important free-energy source in the outer solar atmosphere – the coronal magnetic field. Over its operational lifetime DKIST will advance our knowledge of fundamental astronomical processes, including highly dynamic solar eruptions that are at the source of space-weather events that impact our technological society. Design and construction of DKIST took over two decades. DKIST implements a fast (f/2), off-axis Gregorian optical design. The maximum available field-of-view is 5 arcmin. A complex thermal-control system was implemented in order to remove at prime focus the majority of the 13 kW collected by the primary mirror and to keep optical surfaces and structures at ambient temperature, thus avoiding self-induced local seeing. A high-order adaptive-optics system with 1600 actuators corrects atmospheric seeing enabling diffraction limited imaging and spectroscopy. Five instruments, four of which are polarimeters, provide powerful diagnostic capability over a broad wavelength range covering the visible, near-infrared, and mid-infrared spectrum. New polarization-calibration strategies were developed to achieve the stringent polarization accuracy requirement of 5×10 −4 . Instruments can be combined and operated simultaneously in order to obtain a maximum of observational information. Observing time on DKIST is allocated through an open, merit-based proposal process. DKIST will be operated primarily in “service mode” and is expected to on average produce 3 PB of raw data per year. A newly developed data center located at the NSO Headquarters in Boulder will initially serve fully calibrated data to the international users community. Higher-level data products, such as physical parameters obtained from inversions of spectro-polarimetric data will be added as resources allow.

Much uncertainty remains about the origin and public health implications of livestock-associated methicillin-resistant Staphylococcus aureus (LA-MRSA). This study aimed to investigate the occurrence and prevalence of MRSA in general and LA-MRSA in particular in pigs and farm workers in five states. We collected nasal swabs from pigs and farm workers at 45 swine herds (21 antibiotic-free herds; 24 conventional herds) in Illinois, Iowa, Minnesota, North Carolina and Ohio. MRSA was isolated from 50 of 1085 pigs (4.6%) and 31 of 148 (20.9%) of farm workers. MRSA-positive pigs and people were clustered in four conventional swine farms in Iowa and Illinois. Based on genotyping, spa type t034, a common livestock associated variant, was predominant among both human and swine isolates. These results confirm the presence of LA-MRSA in pigs and swine farm workers in the USA, but the prevalence found is relatively low compared with European studies.