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The COllaborative project of Development of Anthropometrical measures in Twins (CODATwins) project is a large international collaborative effort to analyze individual-level phenotype data from twins in multiple cohorts from different environments. The main objective is to study factors that modify genetic and environmental variation of height, body mass index (BMI, kg/m2) and size at birth, and additionally to address other research questions such as long-term consequences of birth size. The project started in 2013 and is open to all twin projects in the world having height and weight measures on twins with information on zygosity. Thus far, 54 twin projects from 24 countries have provided individual-level data. The CODATwins database includes 489,981 twin individuals (228,635 complete twin pairs). Since many twin cohorts have collected longitudinal data, there is a total of 1,049,785 height and weight observations. For many cohorts, we also have information on birth weight and length, own smoking behavior and own or parental education. We found that the heritability estimates of height and BMI systematically changed from infancy to old age. Remarkably, only minor differences in the heritability estimates were found across cultural–geographic regions, measurement time and birth cohort for height and BMI. In addition to genetic epidemiological studies, we looked at associations of height and BMI with education, birth weight and smoking status. Within-family analyses examined differences within same-sex and opposite-sex dizygotic twins in birth size and later development. The CODATwins project demonstrates the feasibility and value of international collaboration to address gene-by-exposure interactions that require large sample sizes and address the effects of different exposures across time, geographical regions and socioeconomic status.
Ecosystem services typically benefit multiple groups of people. However, natural resource management decisions aiming to secure ecosystem services for one beneficiary group rarely consider potential consequences for others. Here, we examine records of moose hunting in Vermont, USA, a recreational ecosystem service with at least two beneficiary groups: hunters, who benefit from recreational experiences and moose meat, and residents, who live in hunting areas and benefit from hunters’ expenditures. We ask how the allocation of hunting permits has affected (1) the total number of hunters and therefore the benefits enjoyed by this group, (2) the benefits residents received, and (3) the spatial distribution of benefits for each group. We found that changes in the allocation of permits had heterogeneous effects on the beneficiaries. For example, increasing the number of hunting permits increased the total number of hunters, but not necessarily the number of residents who potentially benefit. Also, a more balanced distribution of permits across Vermont increased the total number of potentially benefiting residents, but not those from lower socio-economic groups. Understanding these differences and interactions between beneficiary groups is necessary to distribute benefits equitably amongst them.
Identifying options for the sustainable intensification of cropping systems in southern Africa under prevailing high climate risk is needed. With this in mind, we tested an intercropping system that combined the staple crop maize with lablab, a local but underutilised legume. Grain and biomass productivity was determined for four variants (i) sole maize (sole-maize), (ii) sole lablab (sole-lablab), (iii) maize/lablab with both crops sown simultaneously (intercropped-SP) and (iv) maize/lablab with lablab sown 28 days after the maize crop (intercropped-DP). Soil water and weather data were monitored and evaluated. The trial was conducted for two seasons (2015/2016 and 2016/2017) at two sites in the Limpopo Province, South Africa: Univen (847 mm rainfall, 29.2 °C maximum and 18.9 °C minimum temperature average for the cropping season over the years 2008–2017) and Syferkuil (491 mm rainfall, with 27.0 °C maximum and 14.8 °C minimum temperature). Analysis revealed three key results: The treatment with intercropped-SP had significantly lower maize yields (2320 kg ha−1) compared with maize in intercropped-DP (2865 kg ha−1) or sole-maize (2623 kg ha−1). As expected, maize yields in the El Niño affected in season 2015/2016 were on average 1688 kg ha−1 lower than in 2016/2017. Maize yields were significantly lower (957 kg ha−1) at Univen, the warmer site with higher rainfall, than at Syferkuil. In 2015/2016, maximum temperature at Univen exceeded 40 °C around anthesis. Furthermore, soil water was close to the estimated permanent wilting point (PWP) for most of the cropping season, which indicates possible water limitations. In Syferkuil, the soil water was maintained well above PWP. Lablab yields were low, around 500 ha−1, but stable as they were not affected by treatment across season and site. Overall, the study demonstrated that intercropped-DP appears to use available soil water more efficiently than sole maize. Intercropped-DP could therefore be considered as an option for sustainable intensification under high climate risk and resource-limited conditions for smallholders in southern Africa.
Previous research has discovered different subtypes of social withdrawal based on motivations to approach or avoid social interactions. Each of these motivations are uniquely related to indices of maladjustment during emerging adulthood, including aspects of the self. However, research has yet to investigate whether or not relationship quality moderates these associations. The purpose of this study was to examine whether relationship quality with best friends, romantic partners, mothers, and fathers, respectively, serve as protective factors in the negative links between shyness and avoidance and self-worth. The participants included 519 college students (Mage = 19.87, SD = 1.99, 61% female) from four universities across the United States. Results revealed that relationship quality with both best friends and romantic partners moderated the relation between shyness and self-worth. The differences between parent and peer relationships are discussed.
There are a variety of causes of acute heart failure in children including myocarditis, genetic/metabolic conditions, and congenital heart defects. In cases with a structurally normal heart and a negative personal and family history, myocarditis is often presumed to be the cause, but we hypothesise that genetic disorders contribute to a significant portion of these cases. We reviewed our cases of children who presented with acute heart failure and underwent genetic testing from 2008 to 2017. Eighty-seven percent of these individuals were found to have either a genetic syndrome or pathogenic or likely pathogenic variant in a cardiac-related gene. None of these individuals had a personal or family history of cardiomyopathy that was suggestive of a genetic aetiology prior to presentation. All of these individuals either passed away or were listed for cardiac transplantation indicating genetic testing may provide important information regarding prognosis in addition to providing information critical to assessment of family members.
Introduction: Cardioactive steroid poisoning occurs worldwide with the use of pharmaceutical digoxin and botanical cardiac glycosides. The wholesale price of the antidote, digoxin immune fab, has increased over 300% from 2010 to 2015. Our objective was to identify gaps in the existing literature with respect to the use of digoxin immune fab in cardioactive steroid toxicity in acute care settings. Methods: We used scoping study methodology, as described by Arksey and O'Malley, to assess the range and scope of empiric research and will report: 1) sources of cardioactive steroid toxicity in acute settings; 2) doses of digoxin immune fab used in treatment; and, 3) intervention outcomes of acute cardioactive steroid toxicity following the administration of digoxin immune fab as first or second-line therapy. We collaborated with a library scientist to devise search strategies for PubMed, CINAHL, EMBASE, CENTRAL and Toxnet. We sought unpublished literature through the Canadian Electronic Library, Proquest, and Scopus and searched reference lists of included studies. We hand searched relevant conference proceedings and applicable guidelines. Two reviewers independently reviewed titles and abstracts using predetermined criteria. Using a structured data abstraction form, two reviewers independently extracted data. All discrepancies were resolved through consensus. Results: Our search strategy yielded 3458 results. After screening titles and abstracts 384 underwent full text screening. We included 147 studies and are currently extracting data from 12 French studies and 135 English studies. To date we have extracted data from 90 case reports and case series. Conclusion: Given concerns over rising costs, our findings will shed light on the extent of the evidence for use of digoxin immune fab in acute care settings.
A common property regime was established at the founding of the Maya site of Actuncan, Belize, in the Terminal Preclassic period (175 BC–AD 300), which governed access to land until the Terminal Classic period (AD 780–1000). This interpretation is based on urban settlement patterns documented through household excavation and remote-sensing programs. Excavations of all visible patio-focused groups in the urban core provided data to reconstruct residential histories, and a 60,621 m2 gradiometer survey resulted in a magnetic gradient map that was used to document buried constructions. Twenty ground-truth testpits correlated types of magnetic signatures to buried patio-focused groups and smaller constructions, including walled plots in agricultural field systems that were later exposed more fully through large-scale excavations. Combined, these methods provided data to reconstruct four correlates of land tenure systems: (1) the spatial proximity of residential units to land and resources, (2) diachronic changes in community settlement patterns, (3) land subdivision and improvements, and (4) public goods. Spatial analyses documented that houselots did not cluster through time, but instead became gradually improved, lending evidence to suggest the transgenerational inheritance of property rights in the Late and Terminal Classic periods.
Methods are presented for the determination of uranium, or uranium and neptunium, in plutonium metal and plutonium alloys. Anion exchange or a combination of anion exchange - solvent extraction is used to concentrate the elements for x-ray fluorescence analysis, depending upon the impurities present and the elements to be determined. The precision for determining between 3 and 250 μg of uranium or neptunium ranges “between 30 and 2%.
This paper investigates the diffusion of Pt into polycrystalline thin-film BaxSr1-xTiO3 synthesized by sputter deposition and metal-organic deposition (MOD). Comparison of these two sets of films demonstrated that no remarkable interdiffusion was observed at the Pt/BSTO interface for the sputtered films. This is contrary to the films prepared by MOD which shows Pt has thoroughly diffused into BSTO films. The deeper diffusion of Pt into BSTO films prepared by MOD is attributed to die microstructure of these films. The effects of die diffusion on some physical properties have been discussed. Moreover, the effect of the heat-treatment on the diffusivity and other parameters is discussed
Polypropylene windows stretched to 1-1.5 μm in thickness have been traditionally used for soft x-ray detection on gas flow proportional counters. Theoretical calculations show that significant transmission Improvement could result from a thinner window. The trade-offs to ultimate transmission have traditionally been reliability and durability. A 0.3 um window has been fabricated to show significant improvement for light element transmission, A supporting grid was used to back the film and provide additional support and durability to allow for pressure cycling during venting of the spectrometer chamber. Significant transmission improvements were observed for ultra soft x rays in the energy range below 1 KeV.
The St. Louis aerosol was sampled during the period 16-22 August 1973 simultaneously at two locations using cascade impactors for sequential 12-hour samples. The six particle size fractions of each sampling were individually analyzed using PIXE for elements from S to Br and beyond and for heavy elements including Pb which permitted time variations of concentrations and particle size distributions to be followed and related to meteorological changes during the sampling period. In addition, the data were compared with average levels of the elements in coastal north Florida and maritime Bermuda as well as at a third St. Louis site. From this it appeared that some of the concentrations in St. Louis were at natural levels whereas others appeared to be higher and linked to air pollution sources. These relationships and others in this study may lead to criteria for distinguishing between pollutants and natural background in urban aerosols.
Proton scattering quantitative elemental analysis is examined as a complement to proton induced X-ray emission analysis for air particulate samples. Both methods are absolute, non-destructive, and are suitable for use on samples up to about 1 mg/cm2 in areal density. Characteristics of the method are discussed and examples of aerosol spectra are presented.
Increasing attention is currently focused on the generation of characteristic x-ray by proton irradiation. This has the advantage of yielding “clean” x-ray- i. e. free from background brerasstrahlung radiation, from even the lightest elements. The disadvantage is that the yields are naturally much lower than those produced by electrons of the same energy. A recent study has extended characteristic x-ray production to a variety of heavy ions and has shown that the cross- sections for the production of clean x-rays are often higher , by as much as several orders of magnitude, than those produced by protons of the same energy. In addition, there has emerged a further advantage, viz. the ability of specially chosen heavy ions to excite characteristic x-ray from a particular element in a selective manner. Since heavy ions penetrate only a few hundred Angstroms in to most solids, the phenomenon can be used as the basis of a technique for the examination of surface deposits, or to measure depth distributions of impurities. For example, Kr ions can be used t o determine the range distribution of antimony which had been implanted in to silicon at 100 keV. The antimony concentration was determined as a function of ∼ 150 Å steps, and was found to exhibit a maximum concentration of ∼ 1 part in 103 of silicon at 450 Å below the surface, falling to zero concentration at ∼2000 Å a depth. In the past, in order to obtain the required degree of sensitivity, such range determinations have relied on radio active tracer techniques.
An entirely new type of proportional counter has been developed during the course of these studies. This instrument, because of its special construction, can be positioned very close to targets in non-dispersive studies, so as to collect the highest possible fraction of emitted x-ray. It incorporates a replaceable anode unit, together with a built- in miniature head amplifier, and exhibits extremely good performance, particularly for ultra-soft x-ray. In addition, rotation of a dial on the end of the counter body allows alteration of the active gas volume during operation, and so permits tuning into x-rays of a particular energy.
In this chapter we introduce a framework for qualitatively assessing the security of machine learning systems that captures a broad set of security characteristics common to a number of related adversarial learning settings. There has been a rich set of work that examines the security of machine learning systems; here we survey prior studies of learning in adversarial environments, attacks against learning systems, and proposals for making systems secure against attacks. We identify different classes of attacks on machine learning systems (Section 3.3), categorizing a threat in terms of three crucial properties.
We also present secure learning as a game between an attacker and a defender— the taxonomy determines the structure of the game and its cost model. Further, this taxonomy provides a basis for evaluating the resilience of the systems described by analyzing threats against them to construct defenses. The development of defensive learning techniques is more tentative, but we also discuss a variety of techniques that show promise for defending against different types of attacks.
The work we present not only provides a common language for thinking and writing about secure learning, but goes beyond that to show how the framework applies to both algorithm design and the evaluation of real-world systems. Not only does the framework elicit common themes in otherwise disparate domains but it has also motivated our study of practical machine learning systems as presented in Chapters 5, 6, and 8. These foundational principles for characterizing attacks against learning systems are an essential first step if secure machine learning is to reach its potential as a tool for use in real systems in security-sensitive domains.
This chapter builds on earlier research (Barreno, Nelson, Sears, Joseph, & Tygar 2006; Barreno, Nelson, Joseph, & Tygar 2010; Barreno 2008).
Analyzing the Phases of Learning
Attacks can occur at each of the phases of the learning process that were outlined in Section 2.2. Figure 2.1(a) depicts how data flows through each phase of learning. We briefly outline how attacks against these phases differ.
The Measuring Phase
With knowledge of the measurement process, an adversary can design malicious instances to mimic the measurements of innocuous data. After a successful attack against the measurement mechanism, the system may require expensive reinstrumentation or redesign to accomplish its task.