Terahertz Diagnostic for the Advanced Photon Source Particle Accumulator Ring

Terahertz Diagnostic for the Advanced Photon Source Particle Accumulator Rin

Skeletal trade-offs in coralline algae in response to ocean acidification

Ocean acidification is changing the marine environment, with potentially serious consequences for many organisms. Much of our understanding of ocean acidification effects comes from laboratory experiments, which demonstrate physiological responses over relatively short timescales. Observational studies and, more recently, experimental studies in natural systems suggest that ocean acidification will alter the structure of seaweed communities. Here, we provide a mechanistic understanding of altered competitive dynamics among a group of seaweeds, the crustose coralline algae (CCA). We compare CCA from historical experiments (1981-1997) with specimens from recent, identical experiments (2012) to describe morphological changes over this time period, which coincides with acidification of seawater in the Northeastern Pacific. Traditionally thick species decreased in thickness by a factor of 2.0-2.3, but did not experience a change in internal skeletal metrics. In contrast, traditionally thin species remained approximately the same thickness but reduced their total carbonate tissue by making thinner inter-filament cell walls. These changes represent alternative mechanisms for the reduction of calcium carbonate production in CCA and suggest energetic trade-offs related to the cost of building and maintaining a calcium carbonate skeleton as pH declines. Our classification of stress response by morphological type may be generalizable to CCA at other sites, as well as to other calcifying organisms with species-specific differences in morphological types

Modelling long-distance route choice using mobile phone call detail record data: A case study of Senegal

The growing mobile phone penetration rates have led to the emergence of large-scale call detail records (CDRs) that could serve as a low-cost data source for travel behaviour modelling. However, to the best of our knowledge, there is no previous study evaluating the potential of CDR data in the context of route choice behaviour modelling. Being event-driven, the data are discontinuous and only able to yield partial trajectories, thus presenting serious challenges for route identification. This paper proposes techniques for inferring the users' chosen routes or subsets of their likely routes from partial CDR trajectories, as well as data fusion with external sources of information such as route costs, and then adapts the broad choice framework to the current modelling scenario. The model results show that CDR data can capture the expected travel behaviour and the derived values of travel time are found to be realistic for the study area

The role of intraspecific competition in the dispersal of an invasive fish

1. Ponto‐Caspian gobies are among the most successful fish invaders in inland waters of Europe and in the Great Lakes of North America. Their invasions appear to comprise a combination of passive and active dispersal mechanisms, both natural and human‐mediated. Despite the significance of Ponto‐Caspian gobies as invasive species, there is little information about the mechanisms underpinning their dispersal. They are relatively small benthic fish, with high site affinity. Thus, actively dispersing individuals must express a behavioural motivation to engage in persistent directional movement. 2. Several recent studies have suggested that inter‐individual behavioural differences in boldness, activity level and tendency to explore might underpin dispersal. In addition, because males are highly territorial, intraspecific competition may lead to density‐dependent dispersal of subordinate individuals. To date, studies on this subject have focused mainly on comparisons between individuals from the core of established populations with those at the margins and, thus, address the outcome of dispersal rather than the mechanism itself. 3. We conducted a series of experiments on the racer goby Babka gymnotrachelus to address the question of what behavioural and physiological traits predict the tendency of an individual to perform dispersal behaviour, specifically considering the role of conspecifics in influencing the tendency to disperse. We used an artificial channel to measure dispersal tendency in this species in combination with behavioural trials. 4. Our results showed that fish with a greater tendency to disperse in an experimental channel grew more slowly and were bolder; that is displayed a greater propensity to emerge from a cryptic background onto a white background and performed worse in prey capture trials. As predicted, intraspecific competition played a primary role in the dispersal of the racer goby. Dominant males showed a tendency to monopolise limited shelters with an outcome that subordinates were forced to disperse upstream. The specific growth rate of individuals appeared to be a good indicator of social position. Subordinate males expressed the lowest rates of growth, probably as a result of long‐term deprivation of food in the presence of dominant conspecifics. They were also quicker to explore novel environments, possibly to search for food. Contrary to expectations, subordinate individuals performed relatively poorly in feeding trials when tested individually. 5. Our findings suggest that intraspecific competition in racer goby males is an important mechanism for active dispersal. It can also influence inter‐individual variation in traits such as boldness and tendency to explore novel environments. Similar responses to competitive interactions may have encouraged the invasive expansion of other Ponto‐Caspian gobies following establishment in new environments, as well as other fish species that exhibit territorial behaviour

Compact tokamak reactors. Part 1 (analytic results)

We discuss the possible use of tokamaks for thermonuclear power plants, in particular tokamaks with low aspect ratio and copper toroidal field coils. Three approaches are presented. First we review and summarize the existing literature. Second, using simple analytic estimates, the size of the smallest tokamak to produce an ignited plasma is derived. This steady state energy balance analysis is then extended to determine the smallest tokamak power plant, by including the power required to drive the toroidal field, and considering two extremes of plasma current drive efficiency. The analytic results will be augmented by a numerical calculation which permits arbitrary plasma current drive efficiency; the results of which will be presented in Part II. Third, a scaling from any given reference reactor design to a copper toroidal field coil device is discussed. Throughout the paper the importance of various restrictions is emphasized, in particular plasma current drive efficiency, plasma confinement, plasma safety factor, plasma elongation, plasma beta, neutron wall loading, blanket availability and recirculating electric power. We conclude that the latest published reactor studies, which show little advantage in using low aspect ratio unless remarkably high efficiency plasma current drive and low safety factor are combined, can be reproduced with the analytic model

Comparative morphology of the forewing base articulationin Sternorrhyncha compared with a representative of Fulgoromorpha (Insecta, Hemiptera)

The forewing articulation of single species from each of the four subgroups of Sternorrhyncha (Aleyrodomorpha, Aphidomorpha, Coccomorpha, Psyllomorpha) was examined by optical and scanning electron microscopy. The species were compared with a species of Cixiidae (Fulgoromorpha), as an outgroup of Sternorrhyncha. We present the results of a comparative analysis of the forewing articulation in these five groups, propose a standardized terminology and compare our findings with those previously reported. The wing base of all examined species is composed of the following structures: anterior and posterior notal wing process, first, second, and third axillary sclerites, tegula, and axillary cord. The number of elements included in the wing base and the surrounding area is the greatest in Cacopsylla mali, the most complicated species from Sternorrhyncha. Based on the shape of axillary sclerites and the number of elements forming the wing base environment, Orthezia urticae (Coccomorpha) and Cixius nervosus (Fulgoromorpha) are the most similar. Among Sternorrhyncha, the most similar axillaries are those of Aphis fabae and Orthezia urticae, which is congruent with existing classifications. In this paper we show that the four groups from Sternorrhyncha exhibit their own distinct wing base morphology

Measuring the effects of acupuncture and homoeopathy in general practice: An uncontrolled prospective documentation approach

BACKGROUND: Despite the increasing demand for acupuncture and homoeopathy in Germany, little is known about the effects of these treatments in routine care. We set up a pragmatic documentation study in general practice funded within the scope of project launched by a German health insurer. Patients were followed-up for up to four years. METHODS: The aim of the project was to study the effects and benefits of acupuncture and/or homoeopathy, and to assess patient satisfaction within a prospective documentation of over 5000 acupuncture and over 900 homoeopathy patients. As data sources, we used the documentation made available by therapists on every individual visit and a standardised quality-of-life questionnaire (MOS SF-36); these were complemented by questions concerning the patient's medical history and by questions on patient satisfaction. The health insurer provided us with data on work absenteeism. RESULTS: Descriptive analyses of the main outcomes showed benefit of treatment with middle to large-sized effects for the quality of life questionnaire SF-36 and about 1 point improvement on a rating scale of effects, given by doctors. Data on the treatment and the patients' and physicians' background suggests chronically ill patients treated by fairly regular schemes. CONCLUSION: Since the results showed evidence of a subjective benefit for patients from acupuncture and homoeopathy, this may account for the increase in demand for these treatments especially when patients are chronically ill and unsatisfied with the conventional treatment given previously

Quantum memories at finite temperature

To use quantum systems for technological applications one first needs to preserve their coherence for macroscopic time scales, even at finite temperature. Quantum error correction has made it possible to actively correct errors that affect a quantum memory. An attractive scenario is the construction of passive storage of quantum information with minimal active support. Indeed, passive protection is the basis of robust and scalable classical technology, physically realized in the form of the transistor and the ferromagnetic hard disk. The discovery of an analogous quantum system is a challenging open problem, plagued with a variety of no-go theorems. Several approaches have been devised to overcome these theorems by taking advantage of their loopholes. The state-of-the-art developments in this field are reviewed in an informative and pedagogical way. The main principles of self-correcting quantum memories are given and several milestone examples from the literature of two-, three- and higher-dimensional quantum memories are analyzed

The impacts of environmental warming on Odonata: a review

Climate change brings with it unprecedented rates of increase in environmental temperature, which will have major consequences for the earth's flora and fauna. The Odonata represent a taxon that has many strong links to this abiotic factor due to its tropical evolutionary history and adaptations to temperate climates. Temperature is known to affect odonate physiology including life-history traits such as developmental rate, phenology and seasonal regulation as well as immune function and the production of pigment for thermoregulation. A range of behaviours are likely to be affected which will, in turn, influence other parts of the aquatic ecosystem, primarily through trophic interactions. Temperature may influence changes in geographical distributions, through a shifting of species' fundamental niches, changes in the distribution of suitable habitat and variation in the dispersal ability of species. Finally, such a rapid change in the environment results in a strong selective pressure towards adaptation to cope and the inevitable loss of some populations and, potentially, species. Where data are lacking for odonates, studies on other invertebrate groups will be considered. Finally, directions for research are suggested, particularly laboratory studies that investigate underlying causes of climate-driven macroecological patterns

Palaeozoic giant dragonfies were hawker predators

The largest insects to have ever lived were the giant meganeurids of the Late Palaeozoic, ancient stem relatives of our modern dragonfies. With wingspans up to 71cm, these iconic insects have been the subject of varied documentaries on Palaeozoic life, depicting them as patrolling for prey through coal swamp forests amid giant lycopsids, and cordaites. Such reconstructions are speculative as few defnitive details of giant dragonfy biology are known. Most specimens of giant dragonfies are known from wings or isolated elements, but Meganeurites gracilipes preserves critical body structures, most notably those of the head. Here we show that it is unlikely it thrived in densely forested environments where its elongate wings would have become easily damaged. Instead, the species lived in more open habitats and possessed greatly enlarged compound eyes. These were dorsally hypertrophied, a specialization for long-distance vision above the animal in fight, a trait convergent with modern hawker dragonfies. Sturdy mandibles with acute teeth, strong spines on tibiae and tarsi, and a pronounced thoracic skewness are identical to those specializations used by dragonfies in capturing prey while in fight. The Palaeozoic Odonatoptera thus exhibited considerable morphological specializations associated with behaviours attributable to ‘hawkers’ or ‘perchers’ among extant Odonata.This work benefted from a grant of the French ‘Agence Nationale de la Recherche’ via the program ‘Investissements d’avenir’ (ANR-11-INBS-0004-RECOLNAT)JP and MP gratefully acknowledge research support from the Grant Agency of the Czech Republic No. 18-03118 SThe work of MSE was supported by US National Science Foundation grant DEB-114416