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Recent Anglophone scholarship has successfully shown that Nietzsche's thought makes important contributions to a wide range of contemporary philosophical debates. In so doing, however, scholarship has lost sight of another important feature of Nietzsche's project, namely his desire to challenge the very conception of philosophy that has been used to assess his merits as a philosopher. In other words, contemporary scholarship has overlooked Nietzsche's contributions to metaphilosophy, i.e. debates around the nature, methods, and aims of philosophy. This important new collection of essays brings together an international group of distinguished scholars to explore and discuss these contributions and debates. It will appeal to anyone interested in metaphilosophy, Nietzsche studies, German studies, or intellectual history.
The annihilation of biological diversity is one of the most severe human-induced global environmental problems. Species and populations are being driven to extinction every year at so high a rate, that Earth’s assemblage of plants and animals is now well into a sixth mass extinction episode. The most recent Living Planet Index has estimated that wildlife abundance on the planet dropped by some 60 per cent between 1970 and 2012 (WWF, 2016). The richest biota the world has ever seen is disappearing in the blink of an eye from the perspective of geological time. And humanity is busily making it worse.
Methane contributes substantially to global warming as the second most important anthropogenic greenhouse gas. Radiocarbon (14C) measurements of atmospheric methane can be used as a source apportionment tool, as they allow distinction between thermogenic and biogenic methane sources. However, these measurements remain scarce due to labor-intensive methods required. A new setup for the preparation of atmospheric methane samples for radiocarbon analysis is presented. The system combines a methane preconcentration line with a preparative gas chromatography technique to isolate pure methane samples for a compound-specific radiocarbon analysis. In order to minimize sample preparation time, we designed a simplified preconcentration line for the extraction of methane from 50 L atmospheric air, which corresponds to 50 µg C as required for a reliable 14C analysis of methane-derived CO2 gas measurement with accelerator mass spectrometry (AMS). The system guarantees a quantitative extraction of methane from atmospheric air samples for 14C analysis, with a good repeatability and a low processing blank. The setup was originally designed for the measurement of samples with low methane concentrations, but it can also be adapted to apportion sources from environmental compartments with high methane levels such as freshwaters or wetlands.
This Element looks at the physiological and social roles of taste and the proximal chemical senses. First, how we perceive food and people when we contact them is discussed. These perceptions help us identify what we are eating and with whom we are present and serves as an analysis of the complex scene. Second, the influence of taste in food choice, metabolism, and nutrition is considered. Next, the impact of taste and the proximal chemical senses in social interactions is examined, including social eating. Then, the role of taste and the proximal chemical senses in emotion is explored.
The late Pleistocene–early Holocene archaeological record of the interior Pacific Northwest is dominated by what has been regionally referred to as the Western Stemmed Tradition (WST). While various efforts have attempted to clarify the chronology of this tradition, these have largely focused on data from the Great Basin and have been disproportionately preoccupied with establishing the beginning of the tradition due to its temporal overlap with Clovis materials. Specifically focusing on the Columbia Plateau, we apply a series of Bayesian chronological models to create concise estimates of the most likely beginning, end, and span of the WST. We then further explore its chronology by modeling its temporal span under various parameters and criteria so as to better identify places in the chronology that need further work and those that are robust regardless of data iteration. Our analysis revealed four major findings: (1) WST conservatively dates between 13,000 and 11,000 cal BP, likely extending to ~13,500 cal BP; (2) the most problematic period for WST is its termination; (3) the WST is incredibly long-lived compared to roughly contemporary Paleoindian traditions; and (4) the WST was seemingly unaffected by the onset of the Younger Dryas.
Objective: To investigate the effects of methylphenidate on long-term executive and neuropsychological functioning in children with attention problems following TBI, as well as the relationship between methylphenidate associated changes in lab-based neuropsychological measures of attentional control, processing speed, and executive functioning and parent- or self-report measures of everyday executive functioning. Method: 26 children aged 6–17 years, who were hospitalized for moderate-to-severe blunt head trauma 6 or more months previously, were recruited from a large children’s hospital medical center. Participants were randomized into a double-masked, placebo-controlled cross-over clinical trial. Participants completed a comprehensive neuropsychological battery and parent- and self-report ratings of everyday executive functioning at baseline, and at 4 weeks and 8 weeks following upward titration of medication to an optimal dose or while administered a placebo. Results: Methylphenidate was associated with significant improvements in processing speed, sustained attention, and both lab-based and everyday executive functioning. Significant treatment-by-period interactions were found on a task of sustained attention. Participants who were randomized to the methylphenidate condition for the first treatment period demonstrated random or erratic responding, with slower and more variable response times when given placebo during the second period. Conclusion: Results indicate that methylphenidate treatment is associated with positive outcomes in processing speed, sustained attention, and both lab-based and everyday measures of executive functioning compared to placebo group. Additionally, results suggest sustained attention worsens when discontinuing medication. (JINS, 2019, 25, 740–749)
The Bristol Radiocarbon Accelerator Mass Spectrometry (BRAMS) Facility was established at the University of Bristol after the commissioning of our dedicated sample preparation laboratories and the installation and acceptance of the BrisMICADAS AMS in 2016. Routine measurements commenced in mid-2016, once validation was completed for each sample type. Herein, we give an overview of the standard pretreatment methods currently employed in the Facility and the results of radiocarbon (14C) determinations on a wide range of standards, blank materials, and intercomparison samples which have been measured during our extensive pretreatment method validation program and during our routine 14C analyses.
Synthetic biology has a huge potential to produce the next generation of advanced materials by accessing previously unreachable (bio)chemical space. In this prospective review, we take a snapshot of current activity in this rapidly developing area, focusing on prominent examples for high-performance applications such as those required for protective materials and the aerospace sector. The continued growth of this emerging field will be facilitated by the convergence of expertise from a range of diverse disciplines, including molecular biology, polymer chemistry, materials science, and process engineering. This review highlights the most significant recent advances and addresses the cross-disciplinary challenges currently being faced.
In recent years, an increasing number of online archival databases of primary sources related to the history of the African diaspora and slavery have become freely and readily accessible for scholarly and public consumption. This proliferation of digital projects and databases presents a number of challenges related to aggregating data geographically according to the movement of people in and out of Africa across time and space. As a requirement to linking data of open-source digital projects, it has become necessary to delimit the entire continent of precolonial Africa during the era of the slave trade into broad regions and sub-regions that can allow the grouping of data effectively and meaningfully.
We read with interest the recent editorial, “The Hennepin Ketamine Study,” by Dr. Samuel Stratton commenting on the research ethics, methodology, and the current public controversy surrounding this study.1 As researchers and investigators of this study, we strongly agree that prospective clinical research in the prehospital environment is necessary to advance the science of Emergency Medical Services (EMS) and emergency medicine. We also agree that accomplishing this is challenging as the prehospital environment often encounters patient populations who cannot provide meaningful informed consent due to their emergent conditions. To ensure that fellow emergency medicine researchers understand the facts of our work so they may plan future studies, and to address some of the questions and concerns in Dr. Stratton’s editorial, the lay press, and in social media,2 we would like to call attention to some inaccuracies in Dr. Stratton’s editorial, and to the lay media stories on which it appears to be based.
Ho JD, Cole JB, Klein LR, Olives TD, Driver BE, Moore JC, Nystrom PC, Arens AM, Simpson NS, Hick JL, Chavez RA, Lynch WL, Miner JR. The Hennepin Ketamine Study investigators’ reply. Prehosp Disaster Med. 2019;34(2):111–113
Protected areas are frequently used loci for ecological and conservation research, with several national/international designations identifying scientific research as a key objective. For example, Ecological Stations (ESs) in Brazil are strictly protected areas with the explicit goals of protecting nature and hosting scientific research. Nevertheless, simply mandating scientific research does not necessarily translate into action. Here, we quantitatively assess the scientific productivity of ESs and identify the main socio-ecological factors associated with different levels of scientific research. Specifically, we adopt a multi-model inference approach with a hurdle regression model to independently evaluate the factors associated with the presence/absence of research and the volume of studies in ESs. Surprisingly, given their stated remit, a large proportion of ESs had little or no scientific productivity. Results also indicate that older ESs were more likely to be associated with published research and that the volume of publications was associated with the number of years since the first article was published. The presence of a management plan and a management council were also significant positive drivers of research. Our results strongly suggest that, despite their clear mandate, ESs are not effectively fulfilling their role as a policy instrument for generating valuable scientific data.
Three new tephras have been identified in Southeast Alaska. An 8-cm-thick black basaltic tephra with nine discrete normally graded beds is present in cores from a lake on Baker Island. The estimated age of the tephra is 13,492 ± 237 cal yr BP. Although similar in age to the MEd tephra from the adjacent Mt. Edgecumbe volcanic field, this tephra is geochemically distinct. Black basaltic tephras recovered from two additional sites in Southeast Alaska, Heceta Island and the Gulf of Esquibel, are also geochemically distinct from the MEd tephra. The age of the tephra from Heceta Island is 14,609 ± 343 cal yr BP. Whereas the tephras recovered from Baker Island/Heceta Island/Gulf of Esquibel are geochemically distinct from each other, similarities in the ages of these tephras and the MEd tephra suggest a shared eruptive trigger, possibly crustal unloading caused by retreat of the Cordilleran Ice Sheet. The submerged Addington volcanic field on the continental shelf, which may have been subaerially exposed during the late Pleistocene, is a possible source for the Southeast Alaska tephras.
X-ray elastic constants for the 511+333 and the 422 reflections of β-SiC were calculated from the single crystal data of Tolpygo using the Voigt-Reuss, Eshelby-Kroner and x-ray methods. Agreement was satisfactory for the 511+333, but less so for the 422. A hot-pressed α-Al2O3/ 29 vol % β-SiC (whisker) composite was investigated on its 3 principal faces. The total residual strains were found to be consistently anisotropic on all 3 faces suggesting that texture was present in the whiskers as a result of hot-pressing. Assuming no texture in the matrix, it was found possible to determine the average residual microstresses in the whiskers using the theory of Noyan and Cohen, without needing to know the whisker elastic constants or texture. The average microstresses were determined in each phase as well as the average residual macrostresses on each face.
X-rays can be used to measure residual as well as applied stresses in polymers and reinforced polymeric composites, by diffracting from filler particles that are embedded before curing. We have investigated various fillers that exhibit suitable stress induced shifts of diffraction angle when embedded in uniaxial graphite fiber/epoxy composites. X-ray measurements of elastic strains in the particles are proportional to the corresponding composite strains, in agreement with the model of H. T. Hahn. Results indicate that the stress sensitivity (change in X-ray diffraction angle per MPa applied to the composite) increases in the order W, CdO, Hi, Ag, Nb, Al. With Al 333 + 511 reflections of CuKα1, the diffraction angle shifts 8.52 x 10-4 deg 2θ per MPa. Theoretical predictions are in reasonable agreement with this figure. The elastic range terminates at a yield point beyond which little or no further shift of the diffracted beams is seen for metallic fillers, but no such yield point has appeared with CdO particles. Oppositely directed shifts are seen after unloading from stress levels that have exceeded the yield point.