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Non-structural phenolic compounds perform a variety of functions in plants, including acting as antioxidants. We describe a microplate-adapted colorimetric total phenolics assay that utilizes Folin–Ciocalteu (F–C) reagent. The F–C assay relies on the transfer of electrons in alkaline medium from phenolic compounds to phosphomolybdic/phosphotungstic acid complexes, which are determined spectroscopically at 765 nm. Although the electron transfer reaction is not specific for phenolic compounds, the extraction procedure eliminates approximately 85% of ascorbic acid and other potentially interfering compounds. This assay is performed in microcentrifuge tubes and assessed in a 96-well plate reader. At least 64 samples can be processed in 1 d.

Ascorbate is one of the major antioxidant metabolites in plant tissues. This protocol describes a microplate-adapted colorimetric ascorbate assay, in which ferric ion is reduced by ascorbate to the ferrous ion. The ferrous ion reacts with α-α′-bipyridl to form a complex with characteristic absorbance at 525 nm. With the chemical reduction of any dehydroascorbate (DHA) in a sample, total ascorbate can be assayed using the α-α′-bipyridl method, and DHA can be estimated by subtracting the reduced portion from the total ascorbate pool. The assay is performed in microcentrifuge tubes and assessed in a 96-well plate reader. Reduced ascorbate, DHA and total ascorbate of at least 64 experimental samples can be analyzed easily in 1 d.

Summary Maize is one of the world’s most widely cultivated crops. As future demands for maize will continue to rise, fields will face ever more frequent and extreme weather patterns that directly affect crop productivity. Development of environmentally resilient crops with improved standability in the field, like wheat and rice, was enabled by shifting the architecture of plants to a short stature ideotype. However, such architectural change has not been implemented in maize due to the unique interactions between gibberellin (GA) and floral morphology which limited the use of the same type of mutations as in rice and wheat. Here, we report the development of a short stature maize ideotype in commercial hybrid germplasm, which was generated by targeted suppression of the biosynthetic pathway for GA. To accomplish this, we utilized a dominant, miRNA‐based construct expressed in a hemizygous state to selectively reduce expression of the ZmGA20ox3 and ZmGA20ox5 genes that control GA biosynthesis primarily in vegetative tissues. Suppression of both genes resulted in the reduction of GA levels leading to inhibition of cell elongation in internodal tissues, which reduced plant height. Expression of the miRNA did not alter GA levels in reproductive tissues, and thus, the reproductive potential of the plants remained unchanged. As a result, we developed a dominant, short‐stature maize ideotype that is conducive for the commercial production of hybrid maize. We expect that the new maize ideotype would enable more efficient and more sustainable maize farming for a growing world population.

There is growing interest in measuring the antioxidant status of plant tissues. This protocol describes the oxygen radical absorbance capacity (ORAC) assay, which measures antioxidant inhibition of peroxyl radical–induced oxidations and is a measure of total antioxidant capacity. The assay is performed in a microplate and is assessed with a 96-well multi-detection plate reader. Total antioxidant capacity of 64 experimental samples can easily be analyzed in 1 d. This assay is presented along with rapid assays for total phenolic content and total ascorbate content. Overall, these assays provide a general diagnostic tool of the antioxidant capacity in leaf tissue extracts.

Photosynthetic and respiratory exchanges of CO₂ by plants with the atmosphere are significantly larger than anthropogenic CO₂ emissions, and these fluxes will change as growing conditions are altered by climate change. Understanding feedbacks in CO₂ exchange is important to predicting future atmospheric [CO₂] and climate change. At the tissue and plant scale, respiration is a key determinant of growth and yield. Although the stimulation of C₃ photosynthesis by growth at elevated [CO₂] can be predicted with confidence, the nature of changes in respiration is less certain. This is largely because the mechanism of the respiratory response is insufficiently understood. Molecular, biochemical and physiological changes in the carbon metabolism of soybean in a free-air CO₂ enrichment experiment were investigated over 2 growing seasons. Growth of soybean at elevated [CO₂] (550 μmol·mol⁻¹) under field conditions stimulated the rate of nighttime respiration by 37%. Greater respiratory capacity was driven by greater abundance of transcripts encoding enzymes throughout the respiratory pathway, which would be needed for the greater number of mitochondria that have been observed in the leaves of plants grown at elevated [CO₂]. Greater respiratory quotient and leaf carbohydrate content at elevated [CO₂] indicate that stimulated respiration was supported by the additional carbohydrate available from enhanced photosynthesis at elevated [CO₂]. If this response is consistent across many species, the future stimulation of net primary productivity could be reduced significantly. Greater foliar respiration at elevated [CO₂] will reduce plant carbon balance, but could facilitate greater yields through enhanced photoassimilate export to sink tissues.

Soybeans (Glycine max Merr.) were grown at elevated carbon dioxide concentration ([CO₂]) or chronic elevated ozone concentration ([O₃]; 90 ppb), and then exposed to an acute O₃ stress (200 ppb for 4 h) in order to test the hypothesis that the atmospheric environment alters the total antioxidant capacity of plants, and their capacity to respond to an acute oxidative stress. Total antioxidant metabolism, antioxidant enzyme activity, and antioxidant transcript abundance were characterized before, immediately after, and during recovery from the acute O₃ treatment. Growth at chronic elevated [O₃] increased the total antioxidant capacity of plants, while growth at elevated [CO₂] decreased the total antioxidant capacity. Changes in total antioxidant capacity were matched by changes in ascorbate content, but not phenolic content. The growth environment significantly altered the pattern of antioxidant transcript and enzyme response to the acute O₃ stress. Following the acute oxidative stress, there was an immediate transcriptional reprogramming that allowed for maintained or increased antioxidant enzyme activities in plants grown at elevated [O₃]. Growth at elevated [CO₂] appeared to increase the response of antioxidant enzymes to acute oxidative stress, but dampened and delayed the transcriptional response. These results provide evidence that the growth environment alters the antioxidant system, the immediate response to an acute oxidative stress, and the timing over which plants return to initial antioxidant levels. The results also indicate that future elevated [CO₂] and [O₃] will differentially affect the antioxidant system.

The feminist adage “the personal is political” is not ahistorical. It is being operationalized in a time when the relationship between the private and the public is undergoing historic transformation. Making privatized violence public under current conditions often involves channeling the most authoritarian tendencies of the state into relationships made increasingly desperate by the conditions of contemporary capitalism. The ethnographic focus of the essay is the work of a feminist organization operating in the context of Lavender Hill in Cape Town, a neighborhood created by apartheid forced removals and made more precarious by post-apartheid abandonment. The essay focuses on an explosion in the use of protection orders to compel police to intervene in the intimate relationships of households and neighbors, and offers an extended explanation of how and why feminism provides an exemplary case of reactionary politics for our times. The essay ends with a plea to draw on a different trajectory of feminism as a way of reconstituting a transformative political agenda, one that must take the historical transformations of racial capitalism seriously. [feminism; anti-privatization; protection orders; violence; authoritarianism; neoliberalism; South Africa]

Falling Monuments, Reluctant Ruins: The Persistence of the Past in the Architecture of Apartheid interrogates how, in the era of decolonisation, post-apartheid South Africa reckons with its past in order to shape its future. Architects, historians, artists, social anthropologists and urban planners seek answers in this book to complex and unsettling questions around heritage, ruins and remembrance. What do we do with hollow memorials and political architectural remnants? Which should remain, which forgotten, and which dismantled? Are these vacant buildings, cemeteries, statues, and derelict grounds able to serve as inspiration in the fight against enduring racism and social neglect? Should they become exemplary as spaces for restitution and justice? The contributors examine the influence of public memory, planning and activism on such anguished places of oppression, resistance and defiance. Their focus on visible markers in the landscape to interrogate our past will make readers reconsider these spaces, looking at their landscape and history anew. Through a series of 14 empirically grounded chapters and 48 images, the contributors seek to understand how architecture contests or subverts these persistent conditions in order to promote social justice, land reclamation and urban rehabilitation. The decades following the dismantling of apartheid are surveyed in light of contemporary heritage projects, where building ruins and abandoned spaces are challenged and renegotiated across the country to become sites of protest, inspiration and anger. This ground-breaking collection is an important resource for professionals, academics and activists working in South Africa today. Falling Monuments, Reluctant Ruins: The Persistence of the Past in the Architecture of Apartheid interrogates how, in the era of decolonisation, post-apartheid South Africa reckons with its past in order to shape its future. Architects, historians, artists, social anthropologists and urban planners seek answers in this book to complex and unsettling questions around heritage, ruins and remembrance. What do we do with hollow memorials and political architectural remnants? Which should remain, which forgotten, and which dismantled? The contributors examine the influence of public memory, planning and activism on such anguished places of oppression, resistance and defiance. Their focus on visible markers in the landscape to interrogate our past will make readers reconsider these spaces, looking at their landscape and history anew. Through a series of 14 empirically grounded chapters and over 48 images, the contributors seek to understand how, in the decades following the dismantling of apartheid, architecture contests or subverts these persistent conditions in order to promote social justice, land reclamation and urban rehabilitation. This ground-breaking collection is an important resource for professionals, academics and activists working in South Africa today.

In South Africa in the 1940s, an extensive public discussion about prison reform was led by a powerful collective of white liberals concerned with the growing rates of incarceration in the Union, particularly of urban Africans. This article argues that liberals understood prisons as significant sites in negotiating the 'problems' arising from African urbanism. The large migration of Africans to urban areas during the rapid industrialisation of the 1940s hyperbolised what was known as the 'Native Question', a set of colonialist concerns about how to manage Africans within the changing racial jurisdictions of South African society. Much of the anxiety surrounding the Native Question concerned the threat of African criminality, seen to be located predominantly in the figure of the 'wandering native', either unemployed, unhoused, or simply out of place according to the logics of racialised statutory law. The question of how best to punish this figure elicited extensive research from liberal commentators'. This new form of information drew Africans into a form of governance that rested on ideas of civilisation and 'Christian trusteeship', a term used by one of South Africa's most important penal reformists, anthropologist Winifred Hoernlé. Punishment as an idea as much an institution preoccupied liberals because it threw up for review the critical discussion of social jurisdiction, the responsibilities at stake in the rapidly emerging social contract of industrial capitalism, and the thorny and perduring question of racial difference and universalism.

Purpose - The purpose of this study is to assess the volunteer component of the Neighbors Helping Neighbors (NHN) program, a service program designed to assist community-residing older adults to remain in their homes and avoid premature institutionalization. The study seeks to examine how meaningful and satisfying the volunteer experience has been for individuals involved with NHN.Design methodology approach - This study employed an exploratory cross-sectional survey format developed specifically for NHN for descriptive purposes. A purposive sample of 26 NHN volunteers completed the survey examining their experiences with the NHN program.Findings - A total of 91 percent (21) volunteers reported being \"satisfied\" or \"very satisfied\" with their volunteer experience and 70 percent felt that they had made a difference in their community.Social implications - Programs such as NHN may be promising service models to meet the needs of older adults by building communities from the inside-out.Originality value - This study provides new knowledge concerning the satisfaction of volunteers in a unique community-based program serving older adults.