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Organismal metabolic rates reflect the interaction of environmental and physiological factors. Thus, calcifying organisms that record growth history can provide insight into both the ancient environments in which they lived and their own physiology and life history. However, interpreting them requires understanding which environmental factors have the greatest influence on growth rate and the extent to which evolutionary history constrains growth rates across lineages. We integrated satellite measurements of sea-surface temperature and chlorophyll-a concentration with a database of growth coefficients, body sizes, and life spans for 692 populations of living marine bivalves in 195 species, set within the context of a new maximum-likelihood phylogeny of bivalves. We find that environmental predictors overall explain only a small proportion of variation in growth coefficient across all species; temperature is a better predictor of growth coefficient than food supply, and growth coefficient is somewhat more variable at higher summer temperatures. Growth coefficients exhibit moderate phylogenetic signal, and taxonomic membership is a stronger predictor of growth coefficient than any environmental predictor, but phylogenetic inertia cannot fully explain the disjunction between our findings and the extensive body of work demonstrating strong environmental control on growth rates within taxa. Accounting for evolutionary history is critical when considering shells as historical archives. The weak relationship between variation in food supply and variation in growth coefficient in our data set is inconsistent with the hypothesis that the increase in mean body size through the Phanerozoic was driven by increasing productivity enabling faster growth rates.
Oligodepsipeptides (ODPs) with alternating amide and ester bonds prepared by ring-opening polymerization of morpholine-2,5-dione derivatives are promising matrices for drug delivery systems and building blocks for multifunctional biomaterials. Here, we elucidate the behavior of three telechelic ODPs and one multiblock copolymer containing ODP blocks at the air–water interface. Surprisingly, whereas the oligomers and multiblock copolymers crystallize in bulk, no crystallization is observed at the air–water interface. Furthermore, polarization modulation infrared reflection absorption spectroscopy is used to elucidate hydrogen bonding and secondary structures in ODP monolayers. The results will direct the development of the next ODP-based biomaterial generation with tailored properties for highly sophisticated applications.
A large proportion of the persons who join terrorist groups as well as lone-acting terrorists have a history of violent behavior or mental disorder that predated their becoming terrorists. This suggests that brain alterations found to occur in violent perpetrators may also be present in a significant percentage of terrorists. After a short delineation of phylogenetically old neuronal networks that are important for the generation of aggressive behavior in inconspicuous brains, this review summarizes structural and functional brain-imaging studies in violent offenders published over the last 10 years. Depending on the subtype of violence (impulsive or instrumental), deviations in structure or function were mainly found in the prefrontal, orbitofrontal, and insular cortex, as well as in temporolimbic structures (e.g., the amygdala, hippocampus, and parahippocampus). These brain areas are essentially responsible for the control of the archaic neuronal generators of aggression located in the hypothalamus and limbic system. This regional distribution of brain alterations also shows a remarkable overlap with those brain regions that are crucial for such prosocial traits as empathy and compassion. Feelings of superiority, dominance, and satisfaction gained by performing violent and terroristic attacks suggest that a hedonistic component via an activation of brain reward systems plays an additional role. In our current debate about the causes of terrorism, aspects of brain dysfunction should receive more attention.
We recently started a systematic approach to determine the reservoir age in southeast Arabia and its dependence on mollusk species and their environment. This part of the study concentrates on local reservoir age and stable isotopes of the lagoonal species Terebralia palustris and Anadara uropigimelana at Khor Kalba, Oman Sea. Environmental and nutritive influences on mollusks are reflected in the radiocarbon and stable isotope signal. We found a local reservoir age of A. uropigimelana of about 940 yr and that of T. palustris as 800 yr. Sclerochronological analyses yielded information about seasonality of growth and death in A. uropigimelana. The modern shell of Periglypta reticulata shares food resources and habitat with Anadara sp., of which we did not find a modern specimen. It provided information on response to changes in temperature in the lagoonal system needed for suitability as reflecting climatic conditions. We were interested in carbon pathways of the mangrove in Kalba and a mangrove planted anew on a former mangrove sediment in Ajman. Being an obvious source of charcoal and food of T. palustris makes this information necessary. Further analyses will be performed to interpret changes in reservoir age in complex lagoonal systems as reaction to environmental variability.
Modern observational equipment makes it possible to identify extremely weak metal lines in deep surveys of the optical and near-IR region of the electromagnetic spectrum. In particular, collisionally excited lines from heavy ions (Z > 30) have been recently identified in the spectrum of NGC 7027 (Péquignot & Baluteau 1994). However, detailed quantitative analyses of the observed lines have not been feasible due to the lack of accurate collisional data for the heavy elements.
‘Intimidation through Classicism’ was the heading Brecht gave to his notes on Goethe's Faust in 1964. The colossal scope of this work does indeed have such an intimidating effect that many readers (and the vast majority of directors as well) content themselves with Faust i, not even daring to approach Faust ii, which is almost twice as voluminous. Furthermore, the work as a whole is burdened by 200 years of reception and interpretation, surrounded by countless scholarly interpreters, and completely armed against the curiosity of uninhibited readers with its reputation of fearsome profundity and overwhelming demands. It is easy to see why Thomas Mann wrote to Hermann Hesse that one might be ‘tempted some time to write a totally fresh, intimate commentary on Faust which would relieve people of their all too pious timidity in the face of this sublime, serene, by no means inaccessible work, exceptional and bold but humanly fallible as it is’.
Such a ‘fresh, intimate commentary’ would also have to explain what might otherwise be misunderstood and would certainly be worth understanding correctly. Goethe himself believed that such assistance was required in the case of the great old masters:
Denn bei den alten lieben Toten
Braucht man Erklärung, will man Noten;
Die Neuen glaubt man blank zu verstehn;
Doch ohne Dolmetsch wird's auch nicht gehn.
(BA 1, 441)
For with the old and dear departed
They need explanations, they want notes;
The new ones they think they can understand;
Yet without interpreter they won't succeed, either.
Many applications of high temperature superconductors, HTS, require the presence of lattice defects in the material structure to suppress the motion of magnetic vortices and enhance the critical current density, Jc. The microstructure of Tl2Ba2CaCu2O8-δ (T1–2212) thin films which have extended defects induced by high energy Au and Cu ion irradiation is studied using high resolution transmission electron microscopy, HRTEM, with slow scan digital imaging. In order to optimize the HTS properties and better analyze the consequent microstructural modification, the fluence is varied. At moderate fluences, resulting in ∼4% reduction of the superconducting transition, large enhancements of Jc, and vortex pinning potential are observed. The density and microstructure of isolated defects and surrounding structure will be discussed and compared to damage profiles calculated using the TRIM code. Correlation will be made between the HRTEM results and the changes in HTS properties.
Lattice defects are introduced into the structure to suppress the motion of magnetic vortices and enhance the critical current density in high temperature superconductors. Point defects are not very effective pinning sites for the cuprate superconductors; however, extended defects, such as linear tracks, have been shown to be strong pinning sites. We study the superconducting cuprate TI-2212 (the numbers designate Tl-Ba-Ca-Cu stoichiometry). Large enhancements of vortex pinning potential were observed in TI-2212 after high-intermediate energy heavy-ion irradiations where non-continuous extended defects were induced at dE/dx of 9 to 15.2 keV/nm (60 MeV Au, 60 MeV Cu, and 30 MeV Au) and continuous linear defects were induced at 19.5keV/nm (88MeV Au). Our research addresses the question of pinning in highly anisotropic materials like Tl-2212 where the vortices are “pancakes” rather than “rods” and suitable defect structures may be discontinuous extended damage domains. The defect microstructure and the effectiveness of the pinning potential in TI-2212 after irradiation by intermediate energy Au at lower dE/dx of 5–15 keV/nm, where recoils are more significant, is studied using high resolution transmission electron microscopy digital imaging and a SQUID magnetometer. The nature of the ion irradiation damage at these intermediate dE/dx will be correlated to the average vortex pinning potential and the TRIMRC calculations for recoils.
The coupling of semiconductor field-effect devices (FED) together with chemical and biological recognition elements, like functional intelligent materials, biomolecules and living cells, represents an attractive platform for the creation of different (bio-)chemical sensors, multi-parameter analysis systems and bio-chips. This paper summarises recent developments and current research activities in the field of (bio-)chemically modified FEDs, scaling down from capacitive EIS (electrolyte-insulator-semiconductor) sensors and LAPS (light-addressable potentiometric sensor) to ISFETs (ion-sensitive field-effect transistor) that have been realised in our laboratory. Selected examples of application of ISFETs for the detection of physical parameters in liquids are presented, too. With the aim of future development of nano-devices for the detection of single biomolecules, the possibility of a simple preparation of different self-aligned nano-structures by using conventional photolithography and pattern-size reduction technique has been experimentally demonstrated.
GaxIn1−xAs and GayIn1−yP layers were grown lattice mismatched to GaAs and Ge by low-pressure metal organic vapor phase epitaxy (LP-MOPVE). These materials are very promising for further increasing the efficiency of monolithic triple-junction solar cells. Different buffer layer structures were realized. Transmission electron microscopy and x-ray diffraction analysis were used to characterize the quality of the crystal. Both linear and step-graded buffers in GaxIn1−xAs were successfully used under an active solar cell structure. GayIn1−yP as buffer material showed a worse performance. Excellent solar cell performance was achieved for lattice mismatched single-, dual- and triple-junction solar cells.
Fear conditioning involves the amygdala as the main neural structure for learning fear responses whereas fear extinction mainly activates the inhibitory prefrontal cortex (PFC). In this study we investigated whether individual differences in trait anxiety affect amygdala and dorsal anterior cingulate cortex (dACC) activation during fear conditioning and extinction.
Thirty-two healthy subjects were investigated by functional magnetic resonance imaging (fMRI) at 3 T while performing a cued fear-conditioning task. All participants completed the trait version of the State-Trait Anxiety Inventory (STAI-T). Activations of the amygdala and the dACC were examined with respect to the effects of trait anxiety.
Analysis of the fMRI data demonstrated enhanced activation in fear-related brain areas, such as the insula and the ACC, during both fear conditioning and extinction. Activation of the amygdala appeared only during the late acquisition phase whereas deactivation was observed during extinction. Regression analyses revealed that highly trait-anxious subjects exhibited sustained amygdala activation and reduced dACC involvement during the extinction of conditioned responses.
This study reveals that high levels of trait anxiety are associated with both increased amygdala activation and reduced dACC recruitment during the extinction of conditioned fear. This hyper-responsitivity of the amygdala and the deficient cognitive control during the extinction of conditioned fear in anxious subjects reflect an increased resistance to extinct fear responses and may thereby enhance the vulnerability to developing anxiety disorders.
In this paper, self-recorded interactions from two studies of verbal interaction in Denmark are analysed using key concepts from Erving Goffman's frame analysis and Don Zimmerman's theory of identities in talk. It is documented how the recorder is integrated into everyday interaction as soon as the informant in his or her capacity as temporary fieldworker has explained the reason for its being there and has obtained the permission from his or her partners to record them. In several excerpts ascribed identities and using the recorder as an addressee are used to create amusement and to exploit the possibilities for supplying the innocent overhearing researcher with new and shocking information. The question of language norms during recorded sessions was raised in conversations in both studies and the limits of privacy were brought up.
The queen conch, Strombus gigas, is an important fisheries resource in the Western Tropical Atlantic. In order to maintain harvesting success, improve
fisheries management and contribute to mariculture pursuits, a detailed
understanding of the life history traits of this species is required.
Traditionally, this has been achieved by tedious and time-consuming
long-term field observations. This study presents a highly versatile and
rapid technique to estimate the timing and rate of shell growth based on
sclerochronology. The Belizean S. gigas specimens (N = 2) from the offshore atoll,
Glovers Reef, reached their final shell size (maximum shell height: 22.7 and
23.5 cm, respectively; completed formation of the flared lip) after only two
years. However, seasonal growth rates varied considerably. Shells grew up to
6 mm d−1 during spring (April-June) and fall (September-November) but
only 1 to 2 mm d−1d uring July and August. Furthermore, shell growth
ceased between December and March. Fastest shell growth occurred nearly
contemporaneously with times of maximum precipitation which probably
resulted in increased food availability. Slowest shell growth however,
occurred during times of reduced rainfall and reduced riverine runoff, i.e.
during times of reduced food supply. Sea-water temperature apparently did
not exert a major control on shell growth. Notably, the slow winter growth
was marked by a distinct purple-colored growth line in the cross-sectioned
flared lip. Formation of a second major growth line (brown) fell together with the main
reproduction period (late October/early November). Shell microgrowth
patterns potentially represent daily or semidiurnal periods but cannot be
used to assign exact calendar dates to each shell portion, because they were
not visible across the entire cross-section of the whorl. Also, the
protruding spines developed on the outer shell surface do not function as
time gauges. The time represented by the shell portion between consecutive
spines varies greatly from 1 to 72 days. Sclerochronology can potentially
facilitate maricultural strategies and aid in site pre-testing and selection
to grow S. gigas.