Among the hundreds of thousands of species of beetles, there is one family, containing some 4,300 species, that stands out as one of the most diverse and important groups of aquatic predatory ...insects. This is the Dytiscidae, whose species are commonly known as diving beetles. No comprehensive treatment of this group has been compiled in over 130 years, a period during which a great many changes in classification and a near quadrupling of known species has occurred. In Diving Beetles of the World , Kelly B. Miller and Johannes Bergsten provide the only full treatments of all 186 Dytiscid genera ever assembled. Entomologists, systematists, limnologists, ecologists, and others with an interest in aquatic systems or insect diversity will find these extensively illustrated keys and taxon accounts immensely helpful. The keys make it possible to identify all taxa from subfamily to genera, and each key and taxon treatment is accompanied by both photographs and detailed pen-and-ink drawings of diagnostic features. Every genus account covers body length, diagnostic characters, classification, species diversity, a review of known natural history, and world distribution. Each account is also accompanied by a range map and at least one high-resolution habitus image of a specimen. Diving beetles are fast becoming important models for aquatic ecology, world biogeography, population ecology, and animal sexual evolution and, with this book, the diversity of the group is finally accessible.
Baltimore was once a vibrant manufacturing town, but today, with factory closings and steady job loss since the 1970s, it is home to some of the most impoverished neighborhoods in America.The Hero's ...Fightprovides an intimate look at the effects of deindustrialization on the lives of Baltimore's urban poor, and sheds critical light on the unintended consequences of welfare policy on our most vulnerable communities.
Drawing on her own uniquely immersive brand of fieldwork, conducted over the course of a decade in the neighborhoods of West Baltimore, Patricia Fernández-Kelly tells the stories of people like D. B. Wilson, Big Floyd, Towanda, and others whom the American welfare state treats with a mixture of contempt and pity-what Fernández-Kelly calls "ambivalent benevolence." She shows how growing up poor in the richest nation in the world involves daily interactions with agents of the state, an experience that differs significantly from that of more affluent populations. While ordinary Americans are treated as citizens and consumers, deprived and racially segregated populations are seen as objects of surveillance, containment, and punishment. Fernández-Kelly provides new insights into such topics as globalization and its effects on industrial decline and employment, the changing meanings of masculinity and femininity among the poor, social and cultural capital in poor neighborhoods, and the unique roles played by religion and entrepreneurship in destitute communities.
Blending compelling portraits with in-depth scholarly analysis,The Hero's Fightexplores how the welfare state contributes to the perpetuation of urban poverty in America.
Polyphenols are important components of plants, and contribute to colour, aroma and taste, as well as having many other functions. In recent years, considerable research has been conducted on ...polyphenols in foods, focusing on their bioavailability, metabolism and biological effects. This was driven by results of epidemiological studies which showed that diets rich in plant foods are associated with decreased incidence of cancer and heart diseases. Fruits are rich in polyphenols, and the extraction and enrichment of these bioactive compounds from fruit is of increasing academic and commercial interest.
In this review, the numerous approaches that have been investigated and utilised for the enrichment of polyphenols in foods over the last 20 years or so are discussed, mainly focusing on fruit-based products. This review summarises some important aspects of traditional polyphenol enrichment processes such as solvent extraction, as well as reviewing some novel approaches such as the use of colloidal gas aphrons and ohmic heating. Applications of each process are explained, advantages and disadvantages discussed, and recovery and enrichment levels of polyphenols presented.
Key findings and conclusions: Pre-treatments such as enzymatic hydrolysis, pulsed electric fields and high-pressure processing can be applied to fruit-based products to improve polyphenol extraction efficiency. There is high potential for the use of environmentally friendly processes for enrichment of polyphenols from fruit-based products using membrane filtration. Polyphenol enrichment technologies need to be cost-effective and rapid and facilitate retention of the biological activities of the polyphenols.
•Recovery of polyphenols is widely researched due to their potential applications.•The food industry requires clean and cost-effective polyphenol enrichment processes.•Membrane technology and pressurised liquid extraction are potentially exciting.•Solvent extraction has poor selectivity and generates solvent waste streams.•Pre-treatments, e.g., ohmic heating, can be used to improve extraction efficiency.
Why too much work and too little time is hurting workers and companies—and how a proven workplace redesign can benefit employees and the bottom line
Today's ways of working are not working—even for ...professionals in good jobs. Responding to global competition and pressure from financial markets, companies are asking employees to do more with less, even as new technologies normalize 24/7 job expectations. In Overload , Erin Kelly and Phyllis Moen document how this new intensification of work creates chronic stress, leading to burnout, attrition, and underperformance. Flexible work policies and corporate lip service about work-life balance don't come close to fixing the problem. But this unhealthy and unsustainable situation can be changed—and Overload shows how.
Drawing on five years of research, including hundreds of interviews with employees and managers, Kelly and Moen tell the story of a major experiment that they helped design and implement at a Fortune 500 firm. The company adopted creative and practical work redesigns that gave workers more control over how and where they worked and encouraged managers to evaluate performance in new ways. The result? Employees' health, well-being, and ability to manage their personal and work lives improved, while the company benefited from higher job satisfaction and lower turnover. And, as Kelly and Moen show, such changes can—and should—be made on a wide scale.
Complete with advice about ways that employees, managers, and corporate leaders can begin to question and fix one of today's most serious workplace problems, Overload is an inspiring account about how rethinking and redesigning work could transform our lives and companies.
Interactions between the microbiota and distal gut are fundamental determinants of human health. Such interactions are concentrated at the colonic mucosa and provide energy for the host epithelium ...through the production of the short-chain fatty acid butyrate. We sought to determine the role of epithelial butyrate metabolism in establishing the austere oxygenation profile of the distal gut. Bacteria-derived butyrate affects epithelial O2 consumption and results in stabilization of hypoxia-inducible factor (HIF), a transcription factor coordinating barrier protection. Antibiotic-mediated depletion of the microbiota reduces colonic butyrate and HIF expression, both of which are restored by butyrate supplementation. Additionally, germ-free mice exhibit diminished retention of O2-sensitive dyes and decreased stabilized HIF. Furthermore, the influences of butyrate are lost in cells lacking HIF, thus linking butyrate metabolism to stabilized HIF and barrier function. This work highlights a mechanism where host-microbe interactions augment barrier function in the distal gut.
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•The mammalian colon exists in a state of relative hypoxia•Hypoxic regions of the normal colon provide a signaling axis through HIF-1•Microbial-derived butyrate depletes O2 and activates HIF-1•Microbiota-derived butyrate is barrier-protective in the mucosa
Decreased short-chain fatty acid (SCFA) production by the microbiota has been correlated with colonic inflammation and disease. Kelly et al. show that microbial-derived SCFAs, particularly butyrate, stimulate epithelial metabolism and deplete intracellular O2, resulting in stabilization of the transcription factor HIF-1 and increased epithelial barrier function.
Maximum lifespan in birds and mammals varies strongly with body mass such that large species tend to live longer than smaller species. However, many species live far longer than expected given their ...body mass. This may reflect interspecific variation in extrinsic mortality, as life-history theory predicts investment in long-term survival is under positive selection when extrinsic mortality is reduced. Here, we investigate how multiple ecological and mode-of-life traits that should reduce extrinsic mortality (including volancy (flight capability), activity period, foraging environment and fossoriality), simultaneously influence lifespan across endotherms. Using novel phylogenetic comparative analyses and to our knowledge, the most species analysed to date (n = 1368), we show that, over and above the effect of body mass, the most important factor enabling longer lifespan is the ability to fly. Within volant species, lifespan depended upon when (day, night, dusk or dawn), but not where (in the air, in trees or on the ground), species are active. However, the opposite was true for non-volant species, where lifespan correlated positively with both arboreality and fossoriality. Our results highlight that when studying the molecular basis behind cellular processes such as those underlying lifespan, it is important to consider the ecological selection pressures that shaped them over evolutionary time.
Physical activity (PA) and exercise are among the most important determinants of health. However, PA is a complex and heterogeneous behavior and the biological mechanisms through which it impacts ...individuals and populations in different ways are not well understood. Genetics and environment likely play pivotal roles but further work is needed to understand their relative contributions and how they may be mediated. Metabolomics offers a promising approach to explore these relationships.
In this review, we provide a comprehensive appraisal of the PA-metabolomics literature to date. This overwhelmingly supports the hypothesis of a metabolomic response to PA, which can differ between groups and individuals. It also suggests a biological gradient in this response based on PA intensity, with some evidence for global longer-term changes in the metabolome of highly active individuals. However, many questions remain and we conclude by highlighting future critical research avenues to help elucidate the role of PA in the maintenance of health and the development of disease.
•Physical inactivity is a strong disease risk factor, but mechanisms are elusive.•Metabolomics is ideally suited to explore the physical activity-health relationship.•Literature supports metabolomic response to physical activity and exercise that can differ between individuals.•Volume of physical activity and exercise may be the biggest drivers of the metabolomic adaptions.•Branched chain amino acids, Tricarboxylic Acid (TCA) cycle, oxidative stress and fatty acid mobilization are key.
This paper is an introductory tutorial for numerical trajectory optimization with a focus on direct collocation methods. These methods are relatively simple to understand and effectively solve a wide ...variety of trajectory optimization problems. Throughout the paper we illustrate each new set of concepts by working through a sequence of four example problems. We start by using trapezoidal collocation to solve a simple one-dimensional toy problem and work up to using Hermite-Simpson collocation to compute the optimal gait for a bipedal walking robot. Along the way, we cover basic debugging strategies and guidelines for posing well-behaved optimization problems. The paper concludes with a short overview of other methods for trajectory optimization. We also provide an electronic supplement that contains well-documented MATLAB code for all examples and methods presented. Our primary goal is to provide the reader with the resources necessary to understand and successfully implement their own direct collocation methods.
Theory suggests that evolutionary changes in phenotypic plasticity could either hinder or facilitate evolutionary rescue in a changing climate. Nevertheless, the actual role of evolving plasticity in ...the responses of natural populations to climate change remains unresolved. Direct observations of evolutionary change in nature are rare, making it difficult to assess the relative contributions of changes in trait means versus changes in plasticity to climate change responses. To address this gap, this review explores several proxies that can be used to understand evolving plasticity in the context of climate change, including space for time substitutions, experimental evolution and tests for genomic divergence at environmentally responsive loci. Comparisons among populations indicate a prominent role for divergence in environmentally responsive traits in local adaptation to climatic gradients. Moreover, genomic comparisons among such populations have identified pervasive divergence in the regulatory regions of environmentally responsive loci. Taken together, these lines of evidence suggest that divergence in plasticity plays a prominent role in adaptation to climatic gradients over space, indicating that evolving plasticity is also likely to play a key role in adaptive responses to climate change through time. This suggests that genetic variation in plastic responses to the environment (G × E) might be an important predictor of species' vulnerabilities to climate-driven decline or extinction. This article is part of the theme issue 'The role of plasticity in phenotypic adaptation to rapid environmental change'.
In this book, Robert L. Kelly challenges the preconceptions that hunter-gatherers were Paleolithic relics living in a raw state of nature, instead crafting a position that emphasizes their diversity, ...and downplays attempts to model the original foraging lifeway or to use foragers to depict human nature stripped to its core. Kelly reviews the anthropological literature for variation among living foragers in terms of diet, mobility, sharing, land tenure, technology, exchange, male-female relations, division of labor, marriage, descent and political organization. Using the paradigm of human behavioral ecology, he analyzes the diversity in these areas and seeks to explain rather than explain away variability, and argues for an approach to prehistory that uses archaeological data to test theory rather than one that uses ethnographic analogy to reconstruct the past.
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