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In 2020, the Human Genetics Society of Australasia released its Position Statement on Predictive and Presymptomatic Genetic Testing in Adults and Children. This Position Statement synthesizes the major practical, psychosocial and ethical considerations associated with presymptomatic and predictive genetic testing in adults who have the capacity to make a decision, children and young people who lack capacity and adults living with reduced or fluctuating capacity. Recommendations include that predictive testing in adults, young people and children should only be offered with pretest genetic counseling and the option of posttest genetic counseling. An individual considering (for themselves or on behalf of another) whether to have a predictive test should also be supported to allow them to make an autonomous and informed decision. Predictive testing should only be offered to children and young people for conditions where there is likely to be a direct medical benefit to them through surveillance, use of prevention strategies or other medical interventions in the immediate future. Where symptoms are likely to develop in childhood, in the absence of options to implement surveillance or risk reduction measures, genetic health professionals and parents/guardians should discuss whether undertaking predictive testing is the best course of action for the child and the family as a whole. Where symptoms are likely to develop in adulthood, the default position should be to postpone predictive testing until the young person achieves the capacity to make their own autonomous and informed decision.
Identifying routes of transmission among hospitalized patients during a healthcare-associated outbreak can be tedious, particularly among patients with complex hospital stays and multiple exposures. Data mining of the electronic health record (EHR) has the potential to rapidly identify common exposures among patients suspected of being part of an outbreak.
We retrospectively analyzed 9 hospital outbreaks that occurred during 2011–2016 and that had previously been characterized both according to transmission route and by molecular characterization of the bacterial isolates. We determined (1) the ability of data mining of the EHR to identify the correct route of transmission, (2) how early the correct route was identified during the timeline of the outbreak, and (3) how many cases in the outbreaks could have been prevented had the system been running in real time.
Correct routes were identified for all outbreaks at the second patient, except for one outbreak involving >1 transmission route that was detected at the eighth patient. Up to 40 or 34 infections (78% or 66% of possible preventable infections, respectively) could have been prevented if data mining had been implemented in real time, assuming the initiation of an effective intervention within 7 or 14 days of identification of the transmission route, respectively.
Data mining of the EHR was accurate for identifying routes of transmission among patients who were part of the outbreak. Prospective validation of this approach using routine whole-genome sequencing and data mining of the EHR for both outbreak detection and route attribution is ongoing.
The expansion of genetic and genomic testing in clinical practice and research and the growing market for at home personal genome testing has led to increased awareness about the impact of this form of testing on insurance. Genetic or genomic information can be requested by providers of mutually rated insurance products, who may then use it when setting premiums or determining eligibility for cover under a particular product. Australian insurers are subject to relevant legislation and an industry standard that was updated in late 2016. In 2018, the Human Genetics Society of Australasia updated its position statement on genetic testing and life insurance to account for these changes and to increase the scope of the statement to include a wider scope of insurance products that are not rated according to community risk, such as life, critical care, and income protection products. Recommendations include that providers of professional education involving genetics should include ethical, legal, and social aspects of insurance discrimination in their curricula; that the Australian government take a more active role in regulating use of genetic information in personal insurance, including enacting a moratorium on use of genetic test results; that information obtained in the course of a research project be excluded; and that there is improved engagement between the insurance industry, regulators, and the genetics profession.
Longer-lived cows tend to be more profitable and the stayability trait is a selection criterion correlated to longevity. An alternative to the traditional approach to evaluate stayability is its definition based on consecutive calvings, whose main advantage is the more accurate evaluation of young bulls. However, no study using this alternative approach has been conducted for Zebu breeds. Therefore, the objective of this study was to compare linear random regression models to fit stayability to consecutive calvings of Guzerá, Nelore and Tabapuã cows and to estimate genetic parameters for this trait in the respective breeds. Data up to the eighth calving were used. The models included the fixed effects of age at first calving and year-season of birth of the cow and the random effects of contemporary group, additive genetic, permanent environmental and residual. Random regressions were modeled by orthogonal Legendre polynomials of order 1 to 4 (2 to 5 coefficients) for contemporary group, additive genetic and permanent environmental effects. Using Deviance Information Criterion as the selection criterion, the model with 4 regression coefficients for each effect was the most adequate for the Nelore and Tabapuã breeds and the model with 5 coefficients is recommended for the Guzerá breed. For Guzerá, heritabilities ranged from 0.05 to 0.08, showing a quadratic trend with a peak between the fourth and sixth calving. For the Nelore and Tabapuã breeds, the estimates ranged from 0.03 to 0.07 and from 0.03 to 0.08, respectively, and increased with increasing calving number. The additive genetic correlations exhibited a similar trend among breeds and were higher for stayability between closer calvings. Even between more distant calvings (second v. eighth), stayability showed a moderate to high genetic correlation, which was 0.77, 0.57 and 0.79 for the Guzerá, Nelore and Tabapuã breeds, respectively. For Guzerá, when the models with 4 or 5 regression coefficients were compared, the rank correlations between predicted breeding values for the intercept were always higher than 0.99, indicating the possibility of practical application of the least parameterized model. In conclusion, the model with 4 random regression coefficients is recommended for the genetic evaluation of stayability to consecutive calvings in Zebu cattle.
Shone’s syndrome is a complex consisting of mitral valve stenosis in addition to left ventricle outflow obstruction. There are a few studies evaluating the long-term outcomes in this population. We sought to determine the long-term outcomes in our paediatric population with Shone’s syndrome and the factors associated with left heart growth.
All patients diagnosed with Shone’s syndrome with biventricular circulation treated between 1978 and 2010 were reviewed. Baseline echocardiograms and data from catheterisations were also reviewed. Number of interventions (surgical+transcatheter), incidence of mitral valve replacement, and incidence of heart transplantation were tracked. Survival of the population and left heart structural growth were also reviewed.
A total of 121 patients with Shone’s syndrome presented at a median age of 28 days (0–17.3 years) and were followed-up for 7.2 years (0.01–35.5 years). These patients underwent 258 interventions during the study period, and the presence of coarctation was associated with repeat left heart interventions. The 10-year, transplant-free survival was 86%. Presence of pulmonary hypertension was associated with mortality. Left heart structural growth was seen for mitral and aortic valve annuli and left ventricular end-diastolic dimension over time.
Shone’s syndrome patients undergo a number of left heart interventions. Coarctation of the aorta is associated with an increased likelihood for repeat interventions. Survival appears to be more favourable than expected. Significant left heart growth will occur in the population. Pulmonary hypertension is associated with an increased risk of mortality.
Species with physically dormant (PY) seeds make up over 25% of plant species in a number of ecologically important ecosystems around the globe, such as savannah and Mediterranean shrublands. Many of these ecosystems are subject to temporally stochastic events, such as fire and drought; but are in areas projected to experience some of the most extreme climatic changes in the future. Given the importance of PY in controlling germination timing for successful recruitment, we ask how plastic the PY trait is, and if changes to the maternal environment from climate change could alter recruitment. This review focuses on: (1) the evidence for inter- and intraspecific variation in PY; (2) the genetic, maternal and environmental controls involved; and (3) the ecological consequences of (1) and (2) above. Evidence for (within-community) interspecific variation in conditions required to break PY is strong, but for intraspecific variation evidence is contradictory and limited by a paucity of studies. Identifying controllers of variation in PY is complex, there is some suggestion that conditions of the maternal environment may be important, but no consensus on the nature of effects. The implications of PY plasticity for the persistence of seed banks, species and communities under climate change are discussed. We highlight a number of key knowledge gaps, such as a lack of research estimating the components of variation in non-agricultural species, and identify a suite of seed attributes relevant to understanding the potential impacts of climate change on the population dynamics of PY species in the future.
The high carrier concentrations typically reported for nanowire devices indicate that when Schottky barrier transport is present, it occurs in the thermionic field emission regime with a substantial but not exclusive tunneling component. Analysis by thermionic field emission is difficult due to its multivariate nature. In recent work, we developed a mathematical stability approach that greatly simplified the evaluation of the multivariate thermionic field emission parameters. This is a general method with potentially wide applicability, requiring only the effective mass m* and relative dielectric constant εr for a given semiconductor as inputs. In the present work, we investigate the influence of the materials properties effective mass m* and relative dielectric constant εr on stability for a range of real and simulated semiconductor nanowires. A further investigation of temperature sensitivity and regime trends is presented.
The real-time electronic performance of a gallium nitride nanowire-based field effect transistor was investigated at five-minute intervals over thirty minutes of continuous irradiation by Xenon-124 relativistic heavy ions. An initial current surge that resulted in device improvement rather than device failure was observed. The current surge, and subsequent electronic behavior, was modeled using a combined thermionic emission-tunnelling approach, leading to information about barrier height, carrier concentrations, expected temperature behavior, and tunnelling.
The metal-catalyst-free growth of carbon nanotubes (CNTs) using chemical vapor deposition and the application in field-effect transistors (FETs) is presented. The CNT growth process used a 3-nm-thick Ge layer on SiO2 that was subsequently annealed to produce Ge nanoparticles. Raman measurements show the presence of radial breathing mode (RBM) peaks and the absence of the disorder induced D-band, indicating single walled CNTs (SWNTs) with a low defect density. The synthesized CNTs are used to fabricate CNTFETs and the best device has a state-of-the-art on/off current ratio of 3×108 and a steep sub-threshold slope of 110 mV/decade.
Thin Zn0.98Mn0.02O films were grown by pulsed laser deposition on glass substrates under oxygen pressure. The structural properties were studied by X-ray diffraction and Raman techniques, while the conductivity was characterized by the Hall effect. The oxygen pressure during the growth seems to govern the structural and the electrical properties of the thin Zn0.98Mn0.02 films. In fact, the micron size grain and the resistivity of the Zn0.98Mn0.02O increase with the partial oxygen pressure. However, no evident effect was observed on the magnetic behavior. Electronic structure calculations were performed and magnetic moment carried by Mn atom was computed as well.
We analyzed nitrogen (N) content in phloem and xylem of 75 northern red oak, Quercus rubra L. (Fagaceae), removed in 2002–2007 from three sites within the Ozark National Forest, Arkansas, to investigate the relationship between vascular tissue N status and wood borer infestation. Populations of native red oak borer, Enaphalodes rufulus (Haldeman) (Coleoptera: Cerambycidae), experienced an outbreak and population crash during the sampling period. Vascular tissue N was not correlated with borer infestation density (exit holes/m−2/bark surface), which suggests variation in N status of vascular tissue was not influenced by or did not influence borer success. Vascular tissue N was greater in trees sampled during winter months than in trees sampled in spring and summer months.
The toxicity and palatability of coumatetralyl (3-(α-tetralyl)-4-hydroxycoumarin) to rats (Rattus norvegicus Berk.) were investigated in the laboratory by means of feeding tests. Animals resistant to warfarin (3-(α-acetonylbenzyl)-4-hydroxy-coumarin) and warfarin-resistant rats from infestations refractory to coumatetralyl, as well as non-resistant animals, were employed in the tests.
Medium oatmeal containing a concentration of 0·1% coumatetralyl was not markedly less palatable than the same food unpoisoned. In comparison warfarin at 0·05% but not at 0·025% was significantly less readily eaten than the plain food. Coumatetralyl at 0·05% and 0·005% was about as toxic as 0·005% warfarin is reported to be to non-resistant rats. Warfarin-resistant rats were significantly less susceptible to coumatetralyl than were non-resistant rats. Warfarin-resistant rats from an infestation refractory to coumatetralyl were significantly less susceptible to coumatetralyl than were animals from other sources.
It is considered that coumatetralyl at concentrations of the order of 0·05% in bait would be a good alternative to warfarin against non-resistant rats. While it would be expected that, at this concentration, coumatetralyl would often give good results against warfarin-resistant infestations, this use might eventually produce an increase in the incidence of resistance to both anticoagulants.
We thank Baywood Chemicals Ltd., for supplying the coumatetralyl used in this work. We are also indebted to several colleagues for supplying wild rats and information on field investigations and to Messrs G. Snell and P. Romer for technical assistance.
Wild populations of the Norway rat, Rattus norvegicus, in Jutland have been known to be resistant to the anticoagulant rodenticide warfarin since 1962. The inheritance of the resistance was investigated in the F1, backcross and intercross. The results are consistent with the resistance being due to a major gene at the Rw locus. Resistant homozygotes, heterozygotes and susceptible homozygotes appeared to be distinguishable experimentally on the basis of differences in their susceptibility to vitamin K deficiency. The results are discussed in relation to previous studies of the inheritance of warfarin resistance in rats.
The inheritance of resistance to the rodenticide, warfarin, in the Norway rat, Rattus norvegicus, derived from a wild rat population in Scotland was studied in the backcross, intercross and testcross. The resistance was found to be due to a major gene with about the same map position in Linkage Group I as the warfarin-resistance gene, Rw2, which occurs in the wild rat population in Wales. In heterozygotes, the Scottish resistance gene, unlike the Welsh gene, is incompletely penetrant in expression, though the penetrance was found to increase markedly in response to selection. Differences between the Scottish and Welsh types of resistance suggest that the two resistance genes are allelic.
The frequency of monogenic resistance to anticoagulant rodenticides in Rattus norvegicus in an area straddling the England–Wales border was monitored from 1967 until 1975. Rats were trapped on farms and tested in the laboratory by administering a dose of warfarin lethal to susceptibles. The mean incidence of resistance was 44% and did not change significantly, despite the extensive use of anticoagulants by farmers during the 9-year period. In 1975 more refined techniques showed that the frequencies of susceptible (SS) and resistant (RR) homozygotes were significantly below the Hardy–Weinberg expectations and simple estimates of the relative fitness ratios for the RR, RS and SS phenotypes were 0·37, 1·0 and 0·68 respectively. In two relatively isolated valleys, where selection with anticoagulants was minimal, the frequency of resistance decreased significantly from 57% to 39% during 1973–5. The results are consistent with the hypothesis that a balanced polymorphism is being maintained. Selection against susceptible homozygotes by the use of anticoagulant rodenticides, and against the resistant homozygote due to its high susceptibility to a primary deficiency of vitamin K gives the heterozygotes a selective advantage. A number of ecological factors that influence the incidence of the resistance are discussed briefly.