75 research outputs found
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SEIS: Insight's Seismic Experiment for Internal Structure of Mars.
By the end of 2018, 42 years after the landing of the two Viking seismometers on Mars, InSight will deploy onto Mars' surface the SEIS (Seismic Experiment for Internal Structure) instrument; a six-axes seismometer equipped with both a long-period three-axes Very Broad Band (VBB) instrument and a three-axes short-period (SP) instrument. These six sensors will cover a broad range of the seismic bandwidth, from 0.01 Hz to 50 Hz, with possible extension to longer periods. Data will be transmitted in the form of three continuous VBB components at 2 sample per second (sps), an estimation of the short period energy content from the SP at 1 sps and a continuous compound VBB/SP vertical axis at 10 sps. The continuous streams will be augmented by requested event data with sample rates from 20 to 100 sps. SEIS will improve upon the existing resolution of Viking's Mars seismic monitoring by a factor of ∼ 2500 at 1 Hz and ∼ 200 000 at 0.1 Hz. An additional major improvement is that, contrary to Viking, the seismometers will be deployed via a robotic arm directly onto Mars' surface and will be protected against temperature and wind by highly efficient thermal and wind shielding. Based on existing knowledge of Mars, it is reasonable to infer a moment magnitude detection threshold of M w ∼ 3 at 40 ∘ epicentral distance and a potential to detect several tens of quakes and about five impacts per year. In this paper, we first describe the science goals of the experiment and the rationale used to define its requirements. We then provide a detailed description of the hardware, from the sensors to the deployment system and associated performance, including transfer functions of the seismic sensors and temperature sensors. We conclude by describing the experiment ground segment, including data processing services, outreach and education networks and provide a description of the format to be used for future data distribution.Electronic supplementary materialThe online version of this article (10.1007/s11214-018-0574-6) contains supplementary material, which is available to authorized users
An introduction to Graph Data Management
A graph database is a database where the data structures for the schema
and/or instances are modeled as a (labeled)(directed) graph or generalizations
of it, and where querying is expressed by graph-oriented operations and type
constructors. In this article we present the basic notions of graph databases,
give an historical overview of its main development, and study the main current
systems that implement them
The promoter of ZmMRP-1, a maize transfer cell-specific transcriptional activator, is induced at solute exchange surfaces and responds to transport demands
Transfer cells have specializations that facilitate the transport of solutes across plant exchange surfaces. ZmMRP-1 is a maize (Zea mays) endosperm transfer cell-specific transcriptional activator that plays a central role in the regulatory pathways controlling transfer cell differentiation and function. The present work investigates the signals controlling the expression of ZmMRP-1 through the production of transgenic lines of maize, Arabidopsis, tobacco and barley containing ZmMRP-1promoter:GUS reporter constructs. The GUS signal predominantly appeared in regions of active transport between source and sink tissues, including nematode-induced feeding structures and at sites of vascular connection between developing organs and the main plant vasculature. In those cases, promoter induction was associated with the initial developmental stages of transport structures. Significantly, transfer cells also differentiated in these regions suggesting that, independent of species, location or morphological features, transfer cells might differentiate in a similar way under the influence of conserved induction signals. In planta and yeast experiments showed that the promoter activity is modulated by carbohydrates, glucose being the most effective inducer
2-Amino metabolites are key mediators of CB 1954 and SN 23862 bystander effects in nitroreductase GDEPT
Post-stroke self-management interventions: a systematic review of effectiveness and investigation of the inclusion of stroke survivors with aphasia
Purpose: To systematically review self-management interventions to determine their efficacy for people with stroke in relation to any health outcome and to establish whether stroke survivors with aphasia were included. Method: We searched MEDLINE, EMBASE, PsycINFO, CINAHL, The Cochrane Library, and IBSS and undertook gray literature searches. Randomized controlled trials were eligible if they included stroke survivors aged 18 + in a “self-management” intervention. Data were extracted by two independent researchers and included an assessment of methodological quality. Results: 24 studies were identified. 11 out of 24 reported statistically significant benefits in favor of self-management. However, there were significant limitations in terms of methodological quality, and meta-analyses (n= 8 studies) showed no statistically significant benefit of self-management upon global disability and stroke-specific quality of life at 3 months or ADL at 3 or 6 months follow-up. A review of inclusion and exclusion criteria showed 11 out of 24 (46%) studies reported total or partial exclusion of stroke survivors with aphasia. Four out of 24 (17%) reported the number of stroke survivors with aphasia included. In nine studies (38%) it was unclear whether stroke survivors with aphasia were included or excluded. Conclusions: Robust conclusions regarding the effectiveness of poststroke self-management approaches could not be drawn. Further trials are needed, these should clearly report the population included. •Implications for rehabilitation •There is a lack of evidence to demonstrate the effectiveness of self-management approaches for stroke survivors. •It is unclear whether self-management approaches are suitable for stroke survivors with aphasia, particularly those with moderate or severe aphasia. •Further research is needed to understand the optimal timing for self-management in the stroke pathway and the format in which self-management support should be offered
A nontoxic polypeptide oligomer with a fungicide potency under agricultural conditions which is equal or greater than that of their chemical counterparts
Research ArticleThere are literally hundreds of polypeptides described in the literature which exhibit fungicide
activity. Tens of them have had attempted protection by patent applications but none,
as far as we are aware, have found application under real agricultural conditions. The reasons
behind may be multiple where the sensitivity to the Sun UV radiation can come in first
place. Here we describe a multifunctional glyco-oligomer with 210 kDa which is mainly composed
by a 20 kDa polypeptide termed Blad that has been previously shown to be a stable
intermediary product of β-conglutin catabolism. This oligomer accumulates exclusively in
the cotyledons of Lupinus species, between days 4 and 12 after the onset of germination.
Blad-oligomer reveals a plethora of biochemical properties, like lectin and catalytic activities,
which are not unusual per si, but are remarkable when found to coexist in the same protein
molecule. With this vast range of chemical characteristics, antifungal activity arises
almost as a natural consequence. The biological significance and potential technological
applications of Blad-oligomer as a plant fungicide to agriculture, its uniqueness stems from
being of polypeptidic in nature, and with efficacies which are either equal or greater than the
top fungicides currently in the market are addressedinfo:eu-repo/semantics/publishedVersio
Macroscopic coherent structures in a stochastic neural network: from interface dynamics to coarse-grained bifurcation analysis
We study coarse pattern formation in a cellular automaton modelling a spatially-extended stochastic neural network. The model, originally proposed by Gong and Robinson (Phys Rev E 85(5):055,101(R), 2012), is known to support stationary and travelling bumps of localised activity. We pose the model on a ring and study the existence and stability of these patterns in various limits using a combination of analytical and numerical techniques. In a purely deterministic version of the model, posed on a continuum, we construct bumps and travelling waves analytically using standard interface methods from neural field theory. In a stochastic version with Heaviside firing rate, we construct approximate analytical probability mass functions associated with bumps and travelling waves. In the full stochastic model posed on a discrete lattice, where a coarse analytic description is unavailable, we compute patterns and their linear stability using equation-free methods. The lifting procedure used in the coarse time-stepper is informed by the analysis in the deterministic and stochastic limits. In all settings, we identify the synaptic profile as a mesoscopic variable, and the width of the corresponding activity set as a macroscopic variable. Stationary and travelling bumps have similar meso- and macroscopic profiles, but different microscopic structure, hence we propose lifting operators which use microscopic motifs to disambiguate them. We provide numerical evidence that waves are supported by a combination of high synaptic gain and long refractory times, while meandering bumps are elicited by short refractory times
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Working relationships between obstetric care staff and their managers: a critical incident analysis
Background
Malawi continues to experience critical shortages of key health technical cadres that can adequately respond to Malawi’s disease burden. Difficult working conditions contribute to low morale and frustration among health care workers. We aimed to understand how obstetric care staff perceive their working relationships with managers.
Methods
A qualitative exploratory study was conducted in health facilities in Malawi between October and December 2008. Critical Incident Analysis interviews were done in government district hospitals, faith-based health facilities, and a sample of health centres’ providing emergency obstetric care. A total of 84 service providers were interviewed. Data were analyzed using NVivo 8 software.
Results
Poor leadership styles affected working relationships between obstetric care staff and their managers. Main concerns were managers’ lack of support for staff welfare and staff performance, lack of mentorship for new staff and junior colleagues, as well as inadequate supportive supervision. All this led to frustrations, diminished motivation, lack of interest in their job and withdrawal from work, including staff seriously considering leaving their post.
Conclusions
Positive working relationships between obstetric care staff and their managers are essential for promoting staff motivation and positive work performance. However, this study revealed that staff were demotivated and undermined by transactional leadership styles and behavior, evidenced by management by exception and lack of feedback or recognition. A shift to transformational leadership in nurse-manager relationships is essential to establish good working relationships with staff. Improved providers’ job satisfaction and staff retentionare crucial to the provision of high quality care and will also ensure efficiency in health care delivery in Malawi
Genetic Characterization of Zika Virus Strains: Geographic Expansion of the Asian Lineage
Zika virus (ZIKV) is a mosquito-transmitted flavivirus found in both Africa and Asia. Human infection with the virus may result in a febrile illness similar to dengue fever and many other tropical infections found in these regions. Previously, little was known about the genetic relationships between ZIKV strains collected in Africa and those collected in Asia. In addition, the geographic origins of the strains responsible for the recent outbreak of human disease on Yap Island, Federated States of Micronesia, and a human case of ZIKV infection in Cambodia were unknown. Our results indicate that there are two geographically distinct lineages of ZIKV (African and Asian). The virus has circulated in Southeast Asia for at least the past 50 years, whereupon it was introduced to Yap Island resulting in an epidemic of human disease in 2007, and in 2010 was the cause of a pediatric case of ZIKV infection in Cambodia. This study also highlights the danger of ZIKV introduction into new areas and the potential for future epidemics of human disease
A simple method for defining malaria seasonality
BACKGROUND: There is currently no standard way of defining malaria seasonality, resulting in a wide range of definitions reported in the literature. Malaria cases show seasonal peaks in most endemic settings, and the choice and timing for optimal malaria control may vary by seasonality. A simple approach is presented to describe the seasonality of malaria, to aid localized policymaking and targeting of interventions. METHODS: A series of systematic literature reviews were undertaken to identify studies reporting on monthly data for full calendar years on clinical malaria, hospital admission with malaria and entomological inoculation rates (EIR). Sites were defined as having 'marked seasonality' if 75% or more of all episodes occurred in six or less months of the year. A 'concentrated period of malaria' was defined as the six consecutive months with the highest cumulative proportion of cases. A sensitivity analysis was performed based on a variety of cut-offs. RESULTS: Monthly data for full calendar years on clinical malaria, all hospital admissions with malaria, and entomological inoculation rates were available for 13, 18, and 11 sites respectively. Most sites showed year-round transmission with seasonal peaks for both clinical malaria and hospital admissions with malaria, with a few sites fitting the definition of 'marked seasonality'. For these sites, consistent results were observed when more than one outcome or more than one calendar year was available from the same site. The use of monthly EIR data was found to be of limited value when looking at seasonal variations of malaria transmission, particularly at low and medium intensity levels. CONCLUSION: The proposed definition discriminated well between studies with 'marked seasonality' and those with less seasonality. However, a poor fit was observed in sites with two seasonal peaks. Further work is needed to explore the applicability of this definition on a wide-scale, using routine health information system data where possible, to aid appropriate targeting of interventions
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