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The rocky shores of the north-east Atlantic have been long studied. Our focus is from Gibraltar to Norway plus the Azores and Iceland. Phylogeographic processes shape biogeographic patterns of biodiversity. Long-term and broadscale studies have shown the responses of biota to past climate fluctuations and more recent anthropogenic climate change. Inter- and intra-specific species interactions along sharp local environmental gradients shape distributions and community structure and hence ecosystem functioning. Shifts in domination by fucoids in shelter to barnacles/mussels in exposure are mediated by grazing by patellid limpets. Further south fucoids become increasingly rare, with species disappearing or restricted to estuarine refuges, caused by greater desiccation and grazing pressure. Mesoscale processes influence bottom-up nutrient forcing and larval supply, hence affecting species abundance and distribution, and can be proximate factors setting range edges (e.g., the English Channel, the Iberian Peninsula). Impacts of invasive non-native species are reviewed. Knowledge gaps such as the work on rockpools and host–parasite dynamics are also outlined.
Centenarians have survived into very late life, but whether they reach very old age in good health remains unclear. The purpose of this study was to compare the cardiovascular health status and cognitive functioning of centenarians in the United States with centenarians in Japan.
Design, Setting, and Participants:
This cross-national design compared centenarians from the United States and Japan. The sample of U.S. centenarians was recruited from the Georgia Centenarian Study and included 287 centenarians. The sample of Japanese centenarians was recruited from the Tokyo Centenarian Study and included 304 centenarians.
Cognitive functioning was assessed with a mental status questionnaire, and cardiovascular disease by a health history assessment, blood pressure, and selected blood parameters.
The results suggest that Tokyo centenarians had lower disease experiences and BMI values, when compared to Georgia centenarians, but blood pressure was higher among Japanese centenarians. Lower levels of hemoglobin in Japanese centenarians and higher levels of C-reactive protein in Georgia were also found. The positive association of hypertension and albumin levels with cognitive functioning and the negative association of stroke occurrence with cognitive functioning were replicated in both countries. Differential effects were obtained for heart problems, BMI, and C-reactive protein (with positive effects for Tokyo centenarians, except for C-reactive protein).
For extremely old individuals, some markers of cardiovascular disease are replicable across countries, whereas differential effects for cardiovascular health also need to be considered in cardiovascular health.
Far more than the law has regulated reproduction. Statutes often failed to grasp or change practice, and few cases came to court; popular attitudes, and community pressure, shaped behaviours. Yet disciplinary norms have operated in part through common- law restrictions and a swelling flood of legislation. Formal regulation, however effectively eluded or unevenly enforced, has incited subversion, provoked challenge and offered a yardstick for international comparison.
The major modernizations of legal systems in much of the world in the nineteenth century defined the bourgeois family and brought reproduction within an official framework. Patchworks of laws yielded to single codes for nation-states, which also took over residual legal functions from the Christian churches. For example, the Code Napoléon of 1804, which was emulated especially in Europe and the Middle East, made civil marriage primary and subordinated even aristocratic women to their husbands. In England and Wales, with their system of common or judge-made case law that was influential through the British Empire, the Matrimonial Causes Act 1857 moved divorce from the ecclesiastical to the civil courts and opened it to the middle class, but still favoured men. Laws also defined national populations through obligations to report births, marriages and deaths and complete census forms. Some states obstructed the distribution of contraceptives and criminalized practices that threatened the norm of procreative marital sex, notably abortion and homosexuality.
Early twentieth-century governments legislated more directly to raise population quantity and quality with measures from child tax allowances to compulsory sterilization. They typically proceeded cautiously on such contentious matters, and increasingly deferred to medical practitioners who were themselves often more concerned for their own status. But especially by the 1960s, states and medicine controlled reproduction to such an extent that their paternalism was the chief target of feminist and other reform campaigns. As rights to privacy were recognized and new reproductive technologies introduced, regulators with lay representation came to monitor large medical markets in conception and contraception. This chapter reviews some roles of law in reproduction since around 1800, mainly for the United Kingdom and the United States with their shared emphasis on common law rather than civil codes. Leaving family and population on one side, the focus is on the prevention of births by contraception, sterilization and abortion, the most contested issue, and on their promotion by the techniques of assisted conception for which current regulatory regimes were introduced.
The goal of this study was to perform in situ electrochemical polymerization of poly(3,4-ethylenedioxythiophene) (PEDOT) in peripheral nerves to create a soft, precisely located injectable conductive polymer electrode for bi-directional communication. Intraneural PEDOT polymerization was performed to target both outer and inner fascicles via custom fabricated 3D printed cuff electrodes and monomer injection strategies using a combination electrode-cannula system. Electrochemistry, histology, and laser light sheet microscopy revealed the presence of PEDOT at specified locations inside of peripheral nerve. This work demonstrates the potential for using in situ PEDOT electrodeposition as an injectable electrode for recording and stimulation of peripheral nerves.
The ability to interface electronic materials with the peripheral nervous system is required for stimulation and monitoring of neural signals. Thus, the design and engineering of robust neural interfaces that maintain material-tissue contact in the presence of material or tissue micromotion offer the potential to conduct novel measurements and develop future therapies that require chronic interface with the peripheral nervous system. However, such remains an open challenge given the constraints of existing materials sets and manufacturing approaches for design and fabrication of neural interfaces. Here, we investigated the potential to leverage a rapid prototyping approach for the design and fabrication of nerve cuffs that contain supporting features to mechanically stabilize the interaction between cuff electrodes and peripheral nerve. A hybrid 3D printing and robotic-embedding (i.e., pick-and-place) system was used to design and fabricate silicone nerve cuffs (800 µm diameter) containing conforming platinum (Pt) electrodes. We demonstrate that the electrical impedance of the cuff electrodes can be reduced by deposition of the conducting polymer poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) on cuff electrodes via a post-processing electropolymerization technique. The computer-aided design and manufacturing approach was also used to design and integrate supporting features to the cuff that mechanically stabilize the interface between the cuff electrodes and the peripheral nerve. Both ‘self-locking’ and suture-assisted locking mechanisms are demonstrated based on the principle of making geometric alterations to the cuff opening via 3D printing. Ultimately, this work shows 3D printing offers considerable opportunity to integrate supporting features, and potentially even novel electronic materials, into nerve cuffs that can support the design and engineering of next generation neural interfaces.
Healthy adults (n 30) participated in a placebo-controlled, randomised, double-blinded, cross-over study consisting of two 28 d treatments (β2-1 fructan or maltodextrin; 3×5 g/d) separated by a 14-d washout. Subjects provided 1 d faecal collections at days 0 and 28 of each treatment. The ability of faecal bacteria to metabolise β2-1 fructan was common; eighty-seven species (thirty genera, and four phyla) were isolated using anaerobic medium containing β2-1 fructan as the sole carbohydrate source. β2-1 fructan altered the faecal community as determined through analysis of terminal restriction fragment length polymorphisms and 16S rRNA genes. Supplementation with β2-1 fructan reduced faecal community richness, and two patterns of community change were observed. In most subjects, β2-1 fructan reduced the content of phylotypes aligning within the Bacteroides, whereas increasing those aligning within bifidobacteria, Faecalibacterium and the family Lachnospiraceae. In the remaining subjects, supplementation increased the abundance of Bacteroidetes and to a lesser extent bifidobacteria, accompanied by decreases within the Faecalibacterium and family Lachnospiraceae. β2-1 Fructan had no impact on the metagenome or glycoside hydrolase profiles in faeces from four subjects. Few relationships were found between the faecal bacterial community and various host parameters; Bacteroidetes content correlated with faecal propionate, subjects whose faecal community contained higher Bacteroidetes produced more caproic acid independent of treatment, and subjects having lower faecal Bacteroidetes exhibited increased concentrations of serum lipopolysaccharide and lipopolysaccharide binding protein independent of treatment. We found no evidence to support a defined health benefit for the use of β2-1 fructans in healthy subjects.
Ten ice-sheet models are used to study sensitivity of the Greenland and Antarctic ice sheets to prescribed changes of surface mass balance, sub-ice-shelf melting and basal sliding. Results exhibit a large range in projected contributions to sea-level change. In most cases, the ice volume above flotation lost is linearly dependent on the strength of the forcing. Combinations of forcings can be closely approximated by linearly summing the contributions from single forcing experiments, suggesting that nonlinear feedbacks are modest. Our models indicate that Greenland is more sensitive than Antarctica to likely atmospheric changes in temperature and precipitation, while Antarctica is more sensitive to increased ice-shelf basal melting. An experiment approximating the Intergovernmental Panel on Climate Change’s RCP8.5 scenario produces additional first-century contributions to sea level of 22.3 and 8.1 cm from Greenland and Antarctica, respectively, with a range among models of 62 and 14 cm, respectively. By 200 years, projections increase to 53.2 and 26.7 cm, respectively, with ranges of 79 and 43 cm. Linear interpolation of the sensitivity results closely approximates these projections, revealing the relative contributions of the individual forcings on the combined volume change and suggesting that total ice-sheet response to complicated forcings over 200 years can be linearized.
A new constant-speed penetrometer for field and laboratory measurement has been developed. The initially independent work of SFISAR and CRREL has been brought together, and a portable field device is now in an advanced stage of testing. The new penetrometer has high rigidity and a high-resolution large dynamic range force sensor. It uses a much smaller sensing head (5 mm) than previous designs and has a constant-speed drive. With this construction, the penetration resistance of very fine layers and the influence of the bonding strength between snow grains can be more accurately determined than is possible with the rammsonde or Pandalp. Artificial foam layers as thin as 2 mm and thin layers in snow have been detected by the penetrometer. Thin snow layers detected from penetration-resistance profiles have been correlated to fine layering as determined from plane-section microphotographs of samples taken adjacent to the profile. The instrument’s measurements are highly repeatable and the lack of subjective decisions when operating the penetrometer makes the penetration resistance a quantitative measure of snow stratigraphy.
The ultimatum game is a standard instrument for laboratory experimentalists. It has been replicated in a large number of environments and points to special considerations for fairness. Although it has been popular in the experimental community, researchers have not harnessed all the statistical power they should to evaluate the dynamics at work in this type of a bargaining game. This research uses two planned treatments, the first involving a signaling condition concerning a subject's “type”, and the second a price effect built into the structure of the game. We find that there are no significant main effects as a result of the signaling condition of a subject's type, but that there are strong effects as a result of the different payoff parameters. Using a variety of multivariate models we find important, nonobvious interactions with the gender of the subjects. The lesson that we take away from this research is that experimentalists can learn more from data collected in the tightly controlled laboratory environment by using statistical techniques that complement their research designs.
The dynamic nature of sand dunes over relatively short spatial and temporal scales makes them an ideal phenomenon from which to obtain a better understanding of the interactions between the geosciences and biological sciences. Most early studies of sand dunes focused on classification of dune forms, plant species composition on various dune types, plant succession, and the morphological adaptation of plants to sand burial, salt spray, and xeric conditions. In this chapter, the interaction of ecology and geomorphology in the development of coastal sand dunes will be discussed, from the origin of ecology in the 1800s through to the present. Underlying this history is a struggle by both disciplines to move from a mainly descriptive approach toward an understanding of how sand dunes and plants influence each other. The difficulty has always been how to couple the physical processes of sand transport with the influence of plants and, in turn, how to connect plants with different life histories to sand transport. This undertaking is still in its infancy.
Physiography and Physiographic Ecology
At the end of the 1800s, both physiography (as geomorphology was called at the time) and biology adopted a neo-Lamarckian evolutionary viewpoint (Johnson, 1979; Inkpen and Collier, 2007). Evolution, at this time, incorporated ideas of directional development that could take place at scales above the individual or population (today this idea is called group selection and is mostly rejected as having no valid mechanism (Williams, 1966)). Stages in this directional development were believed to facilitate further evolution. The result was a belief that many forms in biology developed in a progressive, integrated manner with an end-stage that would be in equilibrium. Herbert Spencer, a prolific but now largely forgotten philosopher, was a popular exponent of these ideas, combining both “evolutionary” and “quasi-thermodynamic” ideas in Principles of Biology (1864). He is best remembered for the teleological term “survival of the fittest.”
These evolutionary viewpoints can be found in numerous scientific studies, such as the landscape cycles of Davis (1889; 1899) and in the ecology of communities and succession of Cowles (1899), Clements (1916), and Cooper (1926).
We are not students of some subject matter but students of problems. And problems may cut right across the boundaries of our subject matter and disciplines.
– Karl Popper, 1963. Conjectures and Refutations: Growth of Scientific Knowledge.
This is not an ecosystem textbook in the usual sense in being primarily about biology but rather it is a collateral book that introduces the physical environment into ecosystems using a biogeoscience approach. Why do this? A biogeoscience approach uses: 1) process- or mechanistic-based approaches and 2) formal (mathematical) models of governing equations that involve transport processes and continuity or conservation equations. Ecology has, in general, viewed the physical environment as a black box, using simple arrows to indicate the connections between the physical environment and ecological systems, but with minimal or no consideration of the operation of these physical environmental processes. The reasons for this are varied, but may be attributed partly to different approaches of problem solving in biological vs. geophysical sciences and to both disciplines not always understanding how the other could be connected in more than a descriptive or correlational manner.
The purpose of this book is to take advantage of progress in the geosciences (including geomorphology, soil science, hydrology, and meteorology/climatology) to advance the understanding of ecosystem science. The goal is to present these geoscience developments in a manner such that ecologists who have had limited exposure to these ideas and methods can gain an introduction and understanding of how these couplings can be used in ecosystem science. We intend the book not to be a hopeful discussion of what we should or could be doing to tie the disciplines together, but rather to be a set of chapters providing examples of explicit approaches and procedures of how such research has coupled successfully the fields of ecology and geoscience.
A quick look at the research areas of biogeoscience (Table 1.1) will note large and very active topics (e.g., geomicrobiology) that are not considered in this book. It is easy to think of topics that we could (should) have included in this book.