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The search for life in the Universe is a fundamental problem of astrobiology and modern science. The current progress in the detection of terrestrial-type exoplanets has opened a new avenue in the characterization of exoplanetary atmospheres and in the search for biosignatures of life with the upcoming ground-based and space missions. To specify the conditions favourable for the origin, development and sustainment of life as we know it in other worlds, we need to understand the nature of global (astrospheric), and local (atmospheric and surface) environments of exoplanets in the habitable zones (HZs) around G-K-M dwarf stars including our young Sun. Global environment is formed by propagated disturbances from the planet-hosting stars in the form of stellar flares, coronal mass ejections, energetic particles and winds collectively known as astrospheric space weather. Its characterization will help in understanding how an exoplanetary ecosystem interacts with its host star, as well as in the specification of the physical, chemical and biochemical conditions that can create favourable and/or detrimental conditions for planetary climate and habitability along with evolution of planetary internal dynamics over geological timescales. A key linkage of (astro)physical, chemical and geological processes can only be understood in the framework of interdisciplinary studies with the incorporation of progress in heliophysics, astrophysics, planetary and Earth sciences. The assessment of the impacts of host stars on the climate and habitability of terrestrial (exo)planets will significantly expand the current definition of the HZ to the biogenic zone and provide new observational strategies for searching for signatures of life. The major goal of this paper is to describe and discuss the current status and recent progress in this interdisciplinary field in light of presentations and discussions during the NASA Nexus for Exoplanetary System Science funded workshop ‘Exoplanetary Space Weather, Climate and Habitability’ and to provide a new roadmap for the future development of the emerging field of exoplanetary science and astrobiology.
Biological centrifugation is a process that uses centrifugal force to separate and purify mixtures of biological particles in a liquid medium. The smaller the particles, the higher the g-forces (see next section) required for the separation. It is a key technique for isolating and analysing cells, subcellular fractions, supramolecular complexes and, with higher g-force instruments or ‘ultra’-centrifuges (up to 60 000 revolutions per minute corresponding to ~ 200 000×g) isolated macromolecules such as proteins or nucleic acids. Such high-speed devices require a vacuum to avoid overheating of samples. The development of the first analytical ultracentrifuge – with a specially designed optical system for monitoring and recording the sedimentation process – by Svedberg in the late 1920s and the technical refinement of the preparative centrifugation technique by Claude and colleagues in the 1940s positioned centrifugation technology at the centre of biological and biomedical research for many decades. Today, centrifugation techniques represent a critical tool for modern biochemistry and are employed in almost all invasive subcellular studies. While analytical ultracentrifugation is mainly concerned with the study of purified macromolecules or isolated supramolecular assemblies, preparative centrifugation methodology is devoted to the actual separation of tissues, cells, subcellular structures, membrane vesicles and other particles of biochemical interest.
Most undergraduate students will be exposed to preparative centrifugation protocols during practical classes and might also experience a demonstration of analytical centrifugation techniques. This chapter is accordingly divided into a short introduction into the theoretical background of sedimentation, an overview of practical aspects of using centrifuges in the biochemical laboratory, an outline of preparative centrifugation and a description of the usefulness of ultracentrifugation techniques in the biochemical characterisation of macromolecules. To aid in the understanding of the basic principles of centrifugation, the general designs of various rotors and separation processes are diagrammatically represented. Often, the learning process of undergraduate students is hampered by the lack of a proper linkage between theoretical knowledge and practical applications. To overcome this problem, the description of preparative centrifugation techniques is accompanied by an explanatory flow chart and the detailed discussion of the subcellular fractionation protocol for a specific tissue preparation.
This article documents the development of a community-based drug intervention for low- to mild-risk drug users who surrendered as part of the Philippine government's anti-drug campaign. It highlights the importance of developing evidence-informed drug recovery interventions that are appropriate to the Asian culture and to developing economies. Interviews and consultations with users and community stakeholders reveal the need for an intervention that would improve the drug recovery skills and life skills of users. Evidence-based interventions were adapted using McKleroy and colleagues’ (2006) Map of Adaptation Process (MAP) framework. The resulting intervention reflected the country's collectivist culture, relational values, propensity for indirect and non-verbal communication, and interdependent self-construal. The use of small groups, interactive and creative methodologies, and the incorporation of music and prayer also recognised the importance of these in the Philippine culture.
The mixing of unfamiliar sows at weaning forces the establishment of dominance hierarchies, which frequently involves aggression (Kay et al, 1999). The objective of this study was to determine whether different stocking densities and pen shapes would reduce the incidence of aggression and levels of skin damage. The ultimate aim was to design a mixing pen which could be used to enhance the welfare of groups of newly-weaned sows.
The mixing of unfamiliar sows at weaning leads to aggression whilst dominance hierarchies within the group are established (Kay et al, 1999). The objective of this study was to determine whether the presence of a boar would reduce the incidence of aggression and level of skin damage of newly mixed sows. The overall aim of the project was to improve welfare by designing a suitable strategy for mixing groups of newly-weaned sows
We strongly agree that general intelligence occurs in many animals but find the cultural intelligence hypothesis of limited usefulness. Any viable hypothesis explaining the evolution of general intelligence should be able to account for it in all species where it is known to occur, and should also predict the conditions under which we can develop machines with general intelligence as well.
Training for the clinical research workforce does not sufficiently prepare workers for today’s scientific complexity; deficiencies may be ameliorated with training. The Enhancing Clinical Research Professionals’ Training and Qualifications developed competency standards for principal investigators and clinical research coordinators.
Clinical and Translational Science Awards representatives refined competency statements. Working groups developed assessments, identified training, and highlighted gaps.
Forty-eight competency statements in 8 domains were developed.
Training is primarily investigator focused with few programs for clinical research coordinators. Lack of training is felt in new technologies and data management. There are no standardized assessments of competence.
The translation of discoveries to drugs, devices, and behavioral interventions requires well-prepared study teams. Execution of clinical trials remains suboptimal due to varied quality in design, execution, analysis, and reporting. A critical impediment is inconsistent, or even absent, competency-based training for clinical trial personnel.
In 2014, the National Center for Advancing Translational Science (NCATS) funded the project, Enhancing Clinical Research Professionals’ Training and Qualifications (ECRPTQ), aimed at addressing this deficit. The goal was to ensure all personnel are competent to execute clinical trials. A phased structure was utilized.
This paper focuses on training recommendations in Good Clinical Practice (GCP). Leveraging input from all Clinical and Translational Science Award hubs, the following was recommended to NCATS: all investigators and study coordinators executing a clinical trial should understand GCP principles and undergo training every 3 years, with the training method meeting the minimum criteria identified by the International Conference on Harmonisation GCP.
We anticipate that industry sponsors will acknowledge such training, eliminating redundant training requests. We proposed metrics to be tracked that required further study. A separate task force was composed to define recommendations for metrics to be reported to NCATS.
One case of hospital-acquired listeriosis was linked to milkshakes produced in a commercial-grade shake freezer machine. This machine was found to be contaminated with a strain of Listeria monocytogenes epidemiologically and molecularly linked to a contaminated pasteurized, dairy-based ice cream product at the same hospital a year earlier, despite repeated cleaning and sanitizing. Healthcare facilities should be aware of the potential for prolonged Listeria contamination of food service equipment. In addition, healthcare providers should consider counselling persons who have an increased risk for Listeria infections regarding foods that have caused Listeria infections. The prevalence of persistent Listeria contamination of commercial-grade milkshake machines in healthcare facilities and the risk associated with serving dairy-based ice cream products to hospitalized patients at increased risk for invasive L. monocytogenes infections should be further evaluated.
Due to limitations in available instrumentation and observation time, a spectroscopic determination of distance is not feasible for all objects in the sky. Therefore statistical methods that estimate redshifts, based on photometric measurement are of tremendous importance to many astrophysical questions. Determining cosmological parameters and understanding evolutionary processes in the universe are just two examples. When perform astrophysical analyses, it is necessary to treat the uncertainties of the estimates correctly. Over-simplification of results and the usage of wrong tools to evaluate the performance of probabilistic redshift estimates were commonly found in the literature. We present proper tools for evaluating uncertain redshift estimates and discuss the necessity of multimodal redshift distributions.
Large volumes of data and multiple computing platforms are now universal components of paediatric cardiovascular medicine, but are in a constant state of evolution. Often, multiple sets of related data reside in disconnected “silos”, resulting in clinical, administrative, and research activities that may be duplicative, inefficient, and at times inaccurate. Comprehensive and integrated data solutions are needed to facilitate these activities across congenital heart centres. We describe methodology, key considerations, successful use cases, and lessons learnt in developing an integrated data platform across our congenital heart centre.
Background: The present study explored the reliability, validity, and factor structure of a modified version of the Moral Disengagement Scale (MDS), which comprehensively assesses proneness to disengage from different forms of conduct specific to Australian adolescents. Methods: A sample of 452 students (Mage = 12.79; SD = 1.93) completed the modified MDS and the Australian Self-Report Delinquency Scale. A multistep approach was used to evaluate the factor structure of the MDS. The sample was divided into exploratory (n = 221) and cross-validation samples (n = 231). Principal component analysis was conducted with the exploratory sample and multiple factor solutions compared to determine the optimal factor structure of the modified MDS. The final factor solution was confirmed in the cross-validation sample using confirmatory factor analysis. Internal consistency of the final scale and convergent validity with the delinquency questionnaire was also assessed. Results: Analyses resulted in a 22-item MDS for use in Australia, with four factors mapping onto the four conceptual categories of moral disengagement. The individual subscales demonstrated adequate to good internal consistency, and the total scale also demonstrated high internal consistency (α = 0.87). Convergent validity of the scale was established. Conclusions: The 22-item Australian MDS is a reliable and valid instrument for use within an Australian population.
Kesterite-type compound semiconductors, containing copper and zinc, have photovoltaic properties depending on cation distribution in the crystal structure. Anomalous diffraction allows discrimination of isoelectronic cations, in principle allowing a straightforward determination of site occupation factors from data collected at multiple energies close to the X-ray absorption edges of copper and zinc. However, extremely strong correlation between structural parameters precludes this. We present a recipe based on the direct dependency between refined occupation factors and atomic scattering power, which allows to lift the correlations and to detect issues of individual diffraction patterns or assumptions in the model, thereby allowing for reliable quantitative analysis of the Cu/Zn distribution.
Improvements in colorectal cancer (CRC) detection and treatment have led to greater numbers of CRC survivors, for whom there is limited evidence on which to provide dietary guidelines to improve survival outcomes. Higher intake of red and processed meat and lower intake of fibre are associated with greater risk of developing CRC, but there is limited evidence regarding associations with survival after CRC diagnosis. Among 3789 CRC cases in the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort, pre-diagnostic consumption of red meat, processed meat, poultry and dietary fibre was examined in relation to CRC-specific mortality (n 1008) and all-cause mortality (n 1262) using multivariable Cox regression models, adjusted for CRC risk factors. Pre-diagnostic red meat, processed meat or fibre intakes (defined as quartiles and continuous grams per day) were not associated with CRC-specific or all-cause mortality among CRC survivors; however, a marginal trend across quartiles of processed meat in relation to CRC mortality was detected (P 0·053). Pre-diagnostic poultry intake was inversely associated with all-cause mortality among women (hazard ratio (HR)/20 g/d 0·92; 95 % CI 0·84, 1·00), but not among men (HR 1·00; 95 % CI 0·91, 1·09) (Pfor heterogeneity=0·10). Pre-diagnostic intake of red meat or fibre is not associated with CRC survival in the EPIC cohort. There is suggestive evidence of an association between poultry intake and all-cause mortality among female CRC survivors and between processed meat intake and CRC-specific mortality; however, further research using post-diagnostic dietary data is required to confirm this relationship.
It is unclear whether cryoablation or radiofrequency ablation offers better value for treating atrioventricular nodal re-entrant tachycardia in children. We aimed to compare the value of these procedures for treating atrioventricular nodal re-entrant tachycardia in children, with value being outcomes relative to costs.
We performed a retrospective cohort study of all atrioventricular nodal re-entrant tachycardia ablations for children (age⩽18 years) from July, 2009 to June, 2011 at our institution. Costs included fixed costs, miscellaneous hospital costs, and labour costs, and key outcomes were acute and long-term success (6 months) of the ablations. We conducted T-tests and regression analyses to investigate the associations between the ablation procedure type and the cost and success of the ablations.
Of 96 unique cases performed by three paediatric electrophysiologists, 48 were cryoablation only, 42 radiofrequency ablation only, and six were a combination. Acute success was 100% for the cryoablation only and radiofrequency ablation only cases and 83% for the combination cases. There were no notable adverse events. The average total cost was $9636 for cryoablation cases, $9708 for radiofrequency ablation cases, and $10,967 for combination cases (p=0.51 for cryoablation only versus radiofrequency ablation only). The long-term success rate was 79.1% for cryoablation only, 92.8% for radiofrequency ablation only, and 66.7% for the combination (p=0.01 for cryoablation only versus radiofrequency ablation only), but long-term success varied notably by provider.
Cryoablation and radiofrequency ablation offer similar value in the short term for the treatment of atrioventricular nodal re-entrant tachycardia in children. Differences in long-term success may vary substantially by physician, and thus may lead to differences in long-term value.
The significant impact of extant carnivores, particularly spotted hyenas, on the depositional history and physical characteristics of archaeofaunal and paleontological assemblages is well recognized. We focus on the behavioral ecology of extant spotted hyenas (Crocuta crocuta) in relation to bone accumulations produced by one East African clan at communal dens. Limbs and skulls of prey animals more frequently appear at dens than do other carcass portions. These items reflect the relative abundance of prey species near dens; carnivore remains are poorly represented. Comparative analysis reveals that bones are deposited far more slowly (<7 carcass portions per month) and accumulations tend to be smaller at Crocuta dens than at dens of either brown (Parahyaena brunnea) or striped (Hyaena hyaena) hyenas. We propose that extant Crocuta bone accumulation rates and sizes are likely affected by prey species abundance, clan size, social interactions within the clan, and the type and availability of den sites. We also suggest that the potential for intraspecific behavioral variability in bone accumulation patterns is important when comparisons are made among spotted hyena populations and across hyena species. For example, accumulation patterns may be dramatically influenced by the temporal span, potentially ranging from days to hundreds or thousands of years, in which bones are collected, depending on the species-specific history of occupation at a given site. Understanding the behavioral and ecological variability likely to influence bone accumulation patterns at dens used by different hyaenids will allow taphonomists and zooarchaeologists to refine their knowledge of mechanisms underlying site formation processes and potential causes of variability in deeper-time den assemblages.
To describe trends in country- and individual-level dual burden of malnutrition in children <5 years, and age-stratified (<2 years, ≥2 years) country-level trends, in thirty-six low- and middle-income countries (LMIC).
Using repeated cross-sectional nationally representative data, we calculated the prevalence of malnutrition (stunting, wasting, overweight) at each survey wave, annualized rates of prevalence change for each country over time, and trends before and after 2000, for all children <5 years and separately for those </≥2 years. We examined country- (ratio of stunting to overweight) and individual-level (coexistence of stunting and overweight) dual burden in children <5 years.
Demographic and Health Surveys from thirty-six LMIC between 1990 and 2012.
Children <5 years.
Overall malnutrition prevalence decreased in children <5 years, driven by stunting decreases. Stunting rates decreased in 78 % of countries, wasting rates decreased in 58 % of countries and overweight rates increased in 36 % of countries. Rates of change differed for children </≥2 years, with children <2 years experiencing decreases in stunting in fewer countries yet increases in overweight in more countries. Countries with nearly equal prevalences of stunting and overweight in children <5 years increased from 2000 to the final year. Within a country, 0·3–10·9 % of children <5 years were stunted and overweight, and 0·6–37·8 % of stunted children <5 years were overweight.
The dual burden exists in children <5 years on both country and individual levels, indicating a shift is needed in policies and programmes to address both sides of malnutrition. Children <2 years should be identified as a high-risk demographic.
This article documents the prevalence in organized interest politics in the United States of organizations—for example, corporations, think tanks, universities, or hospitals—that have no members in the ordinary sense and analyzes the consequences of that dominance for the democratic representation of citizen interests. We use data from the Washington Representatives Study, a longitudinal data base containing more than 33,000 organizations active in national politics in 1981, 1991, 2001, 2006, and 2011. The share of membership associations active in Washington has eroded over time until, in 2011, barely a quarter of the more than 14,000 organizations active in Washington in 2011 were membership associations, and less than half of those were membership association with individuals as members. In contrast, a majority of the politically involved organizations were memberless organizations, of which nearly two-thirds were corporations. The dominance of memberless organizations in pressure politics raises important questions about democratic representation. Studies of political representation by interest groups raise several concerns about democratic inequalities: the extent to which representation of interests by groups is unequal, the extent to which groups fail to represent their members equally, and the extent to which group members are unable to control their leaders. All of the dilemmas that arise when membership associations advocate in politics become even more intractable when organizations do not have members.
Solidarity is supposed to facilitate collective action. We argue that it can also help overcome false consciousness. Groups practice ‘epistemic solidarity’ if they pool information about what is in their true interest and how to vote accordingly. The more numerous ‘Masses’ can in this way overcome the ‘Elites,’ but only if they are minimally confident with whom they share the same interests and only if they are (perhaps only just) better-than-random in voting for the alternative that promotes their interests. Being more cohesive and more competent than the Masses, the Elites can employ the same strategy perhaps all the more effectively. But so long as the Masses practice epistemic solidarity they will almost always win, whether or not the Elites do. By enriching the traditional framework of the Condorcet Jury Theorem with group-specific standards of correctness, we investigate how groups can organize to support the alternatives truly in their interests.