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Sea-level rise threatens both human communities and vulnerable species within coastal areas. Joint spatial planning can allow conservation and social resiliency goals to work in synergy. We present a case study integrating distribution information of a threatened saltmarsh bird, the eastern black rail (Laterallus jamaicensis jamaicensis), with social information to facilitate such joint planning. We constructed a distribution model for the species within an urbanizing coastal region (New Jersey, USA) and integrated this with publicly available parcel and protected area data to summarize ownership patterns. We estimated that c. 0.3–2.8% (c. 260–2200 ha) of available saltmarsh is occupied by eastern black rail, most of which is publicly owned (79%). Privately owned saltmarsh was spread across nearly 5000 individual parcels, 10% of which contained areas with the highest likelihood of rail presence according to our model (top quartile of predicted occupancy probabilities). Compared with all privately owned saltmarsh, parcels with probable rail habitat were larger (median: 5 versus 2 ha), contained more marsh (87% versus 59%) and were less economically valuable (US$11 200 versus US$36 100). Our approach of integrating species distributions with landownership data helps clarify trade-offs and synergies in species conservation and coastal resiliency planning.
Since its founding in 1971, the United Arab Emirates (UAE) has advanced rapidly and emerged as a global leader in innovation. One of the best examples of this progress is the development of a comprehensive federal university system and a well-articulated vision and framework for building a highly educated workforce who possess twenty-first-century skills and who will be key players in a knowledge-based economy. This chapter explores the role of undergraduate research within the UAE’s federal university system, and the role for these programmes in national capacity development. Model programmes at each of the UAE’s three federal higher education institutions are explored, and recommendations for policy and practice related to undergraduate research are discussed.
More than 80% of the people of Papua New Guinea (PNG) live in rural areas and produce most of the calories they consume. The rest comes from imported food, mainly rice and wheat. An estimated 83% of all food energy consumed in PNG in 2006 was derived from locally grown food. Rapid population change, an HIV/AIDS epidemic, and global climate change are the main threats to the sustainable production of this food into the future. Rapid population change threatens to bring about land degradation in shifting cultivation systems; also, HIV/AIDS will slow population growth but will selectively remove working-age people from the population, while the outcomes of global warming are less certain. Global warming is apparent in rises in temperatures and some observable changes in plant distributions. If global climate change increases the frequency of El Niño-Southern Oscillation (ENSO) events, then food production will be adversely affected. On the other hand, global warming may have some positive effects. Governance in PNG is poor, so rural people will have to face the outcomes of these three threats largely using their own resources of resilience, innovativeness, and hard work.
Barrows are a prominent feature of Britain's Bronze Age landscape. While they originated as burial monuments, they also appear to have acquired other roles in prehistory. British prehistorians, however, have been hampered in their interpretations of these monuments, as they are wary of speculating about how Bronze Age people might have conceptualised their dead. Here, the authors suggest that a recurring pattern of inversion is significant. They use Conceptual Metaphor Theory to argue that Bronze Age people in Britain saw their dead inhabiting an inverted underworld directly beneath the surface of the earth. This interpretation would explain not only burial practices, but also some of the barrows’ other apparent functions, such as guarding boundaries and controlling routeways.
Colleges and universities around the world engaged diverse strategies during the COVID-19 pandemic. Baylor University, a community of ˜22,700 individuals, was 1 of the institutions which resumed and sustained operations. The key strategy was establishment of multidisciplinary teams to develop mitigation strategies and priority areas for action. This population-based team approach along with implementation of a “Swiss Cheese” risk mitigation model allowed small clusters to be rapidly addressed through testing, surveillance, tracing, isolation, and quarantine. These efforts were supported by health protocols including face coverings, social distancing, and compliance monitoring. As a result, activities were sustained from August 1 to December 8, 2020. There were 62,970 COVID-19 tests conducted with 1435 people testing positive for a positivity rate of 2.28%. A total of 1670 COVID-19 cases were identified with 235 self-reports. The mean number of tests per week was 3500 with approximately 80 of these positive (11/d). More than 60 student tracers were trained with over 120 personnel available to contact trace, at a ratio of 1 per 400 university members. The successes and lessons learned provide a framework and pathway for similar institutions to mitigate the ongoing impacts of COVID-19 and sustain operations during a global pandemic.
Non-invasive prenatal testing (NIPT) for the detection of foetal aneuploidy through analysis of cell-free DNA (cfDNA) in maternal blood is offered routinely by many healthcare providers across the developed world. This testing has recently been recommended for evaluative implementation in the UK National Health Service (NHS) foetal anomaly screening pathway as a contingent screen following an increased risk of trisomy 21, 18 or 13. In preparation for delivering a national service, we have implemented cfDNA-based NIPT in our Regional Genetics Laboratory. Here, we describe our validation and verification processes and initial experiences of the technology prior to rollout of a national screening service.
Data are presented from more than 1000 patients (215 retrospective and 840 prospective) from ‘high- and low-risk pregnancies’ with outcome data following birth or confirmatory invasive prenatal sampling. NIPT was by the Illumina Verifi® test.
Our data confirm a high-fidelity service with a failure rate of ~0.24% and a high sensitivity and specificity for the detection of foetal trisomy 13, 18 and 21. Secondly, the data show that a significant proportion of patients continue their pregnancies without prenatal invasive testing or intervention after receiving a high-risk cfDNA-based result. A total of 46.5% of patients referred to date were referred for reasons other than high screen risk. Ten percent (76/840 clinical service referrals) of patients were referred with ultrasonographic finding of a foetal structural anomaly, and data analysis indicates high- and low-risk scan indications for NIPT.
NIPT can be successfully implemented into NHS regional genetics laboratories to provide high-quality services. NHS provision of NIPT in patients with high-risk screen results will allow for a reduction of invasive testing and partially improve equality of access to cfDNA-based NIPT in the pregnant population. Patients at low risk for a classic trisomy or with other clinical indications are likely to continue to access cfDNA-based NIPT as a private test.
To define optimal thromboprophylaxis strategy after stent implantation in superior or total cavopulmonary connections.
Stent thrombosis is a rare complication of intravascular stenting, with a perceived higher risk in single-ventricle patients.
All patients who underwent stent implantation within superior or total cavopulmonary connections (caval vein, innominate vein, Fontan, or branch pulmonary arteries) were included. Cohort was divided into aspirin therapy alone versus advanced anticoagulation, including warfarin, enoxaparin, heparin, or clopidogrel. Primary endpoint was in-stent or downstream thrombus, and secondary endpoints included bleeding complications.
A total of 58 patients with single-ventricle circulation underwent 72 stent implantations. Of them 14 stents (19%) were implanted post-superior cavopulmonary connection and 58 (81%) post-total cavopulmonary connection. Indications for stenting included vessel/conduit stenosis (67%), external compression (18%), and thrombotic occlusion (15%). Advanced anticoagulation was prescribed for 32 (44%) patients and aspirin for 40 (56%) patients. Median follow up was 1.1 (25th–75th percentile, 0.5–2.6) years. Echocardiograms were available in 71 patients (99%), and advanced imaging in 44 patients (61%). Thrombosis was present in two patients on advanced anticoagulation (6.3%) and none noted in patients on aspirin (p = 0.187). Both patients with in-stent thrombus underwent initial stenting due to occlusive left pulmonary artery thrombus acutely post-superior cavopulmonary connection. There were seven (22%) significant bleeding complications for advanced anticoagulation and none for aspirin (p < 0.001).
Antithrombotic strategy does not appear to affect rates of in-stent thrombus in single-ventricle circulations. Aspirin alone may be sufficient for most patients undergoing stent implantation, while pre-existing thrombus may warrant advanced anticoagulation.
Transcatheter right ventricle decompression in neonates with pulmonary atresia and intact ventricular septum is technically challenging, with risk of cardiac perforation and death. Further, despite successful right ventricle decompression, re-intervention on the pulmonary valve is common. The association between technical factors during right ventricle decompression and the risks of complications and re-intervention are not well described.
This is a multicentre retrospective study among the participating centres of the Congenital Catheterization Research Collaborative. Between 2005 and 2015, all neonates with pulmonary atresia and intact ventricular septum and attempted transcatheter right ventricle decompression were included. Technical factors evaluated included the use and characteristics of radiofrequency energy, maximal balloon-to-pulmonary valve annulus ratio, infundibular diameter, and right ventricle systolic pressure pre- and post-valvuloplasty (BPV). The primary end point was cardiac perforation or death; the secondary end point was re-intervention.
A total of 99 neonates underwent transcatheter right ventricle decompression at a median of 3 days (IQR 2–5) of age, including 63 patients by radiofrequency and 32 by wire perforation of the pulmonary valve. There were 32 complications including 10 (10.5%) cardiac perforations, of which two resulted in death. Cardiac perforation was associated with the use of radiofrequency (p=0.047), longer radiofrequency duration (3.5 versus 2.0 seconds, p=0.02), and higher maximal radiofrequency energy (7.5 versus 5.0 J, p<0.01) but not with patient weight (p=0.09), pulmonary valve diameter (p=0.23), or infundibular diameter (p=0.57). Re-intervention was performed in 36 patients and was associated with higher post-intervention right ventricle pressure (median 60 versus 50 mmHg, p=0.041) and residual valve gradient (median 15 versus 10 mmHg, p=0.046), but not with balloon-to-pulmonary valve annulus ratio, atmospheric pressure used during BPV, or the presence of a residual balloon waist during BPV. Re-intervention was not associated with any right ventricle anatomic characteristics, including pulmonary valve diameter.
Technical factors surrounding transcatheter right ventricle decompression in pulmonary atresia and intact ventricular septum influence the risk of procedural complications but not the risk of future re-intervention. Cardiac perforation is associated with the use of radiofrequency energy, as well as radiofrequency application characteristics. Re-intervention after right ventricle decompression for pulmonary atresia and intact ventricular septum is common and relates to haemodynamic measures surrounding initial BPV.
To evaluate differences in interstage growth of pulmonary arteries between use of polytetrafluoroethylene and femoral vein homograft as Sano shunt during stage-I Norwood palliation.
A retrospective review of all patients who survived to the second stage following Norwood–Sano operation at two institutions was performed. Either polytetrafluoroethylene or the valved segment of femoral vein homograft was used for construction of the Sano shunt. The size of pulmonary arteries was compared at pre-Glenn catheterisation.
A total of 48 neonates with the diagnosis of hypoplastic left heart syndrome or its variants comprised the study population. Femoral vein homograft of 5–6 mm diameter was used in 14 and polytetrafluoroethylene graft of 5 mm was used in 34 patients. The two groups were comparable in terms of preoperative demographics and age at time of pre-Glenn catheterisation (3.9±0.7 versus 3.4±0.8 months, p=0.06). Patients who received femoral vein homograft demonstrated a significantly higher pre-Glenn Nakata index [264 (130–460) versus 165 (108–234) mm2/m2, p=0.004]. The individual branch pulmonary arteries were significantly larger in the femoral vein group (right, 7.8±3.6 versus 5.0±1.2, p=0.014; left, 7.2±2.1 versus 5.6±1.9, p=0.02). There were no differences in cardiac index, Qp:Qs, ventricular end-diastolic pressure or systemic oxygen saturations.
Utilisation of a valved segment of femoral vein homograft as right ventricle to pulmonary artery conduit during Norwood–Sano operation confers better interstage growth of the pulmonary arteries. Further studies are needed to evaluate the impact of femoral vein homograft on single ventricle function.
After the Portuguese discovered the Cape Verde Islands in AD 1456 they divided its main island, Santiago, into two governing captaincies. The founding settlement in the south-west, Cidade Velha, soon became the Islands’ capital and a thriving trade centre; in contrast, that in the east, Alcatrazes, only lasted as an official seat from 1484–1516 and is held to have ‘failed’ (see Richter 2015).
Stonehenge is a site that continues to yield surprises. Excavation in 2009 added a new and unexpected feature: a smaller, dismantled stone circle on the banks of the River Avon, connected to Stonehenge itself by the Avenue. This new structure has been labelled ‘Bluestonehenge’ from the evidence that it once held a circle of bluestones that were later removed to Stonehenge. Investigation of the Avenue closer to Stonehenge revealed deep periglacial fissures within it. Their alignment on Stonehenge's solstitial axis (midwinter sunset–midsummer sunrise) raises questions about the early origins of this ritual landscape.
We describe a versatile infrared camera/spectrograph, IRIS, designed and constructed at the Anglo-Australian Observatory for use on the Anglo-Australian Telescope. A variety of optical configurations can be selected under remote control to provide several direct image scales and a few low-resolution spectroscopic formats. Two cross-dispersed transmission echelles are of novel design, as is the use of a modified Bowen-Burch system to provide a fast f/ratio in the widest-field option. The drive electronics includes a choice of readout schemes for versatility, and continuous display when the array is not taking data, to facilitate field acquisition and focusing.
The linearity of the detector has been studied in detail. Although outwardly good, slight nonlinearities prevent removal of fixed-pattern noise from the data without application of a cubic linearising function.
Specific control and data-reduction software has been written. We describe also a scanning mode developed for spectroscopic imaging.
Our knowledge of the universe comes from recording the photon and particle fluxes incident on the Earth from space. We thus require sensitive measurement across the entire energy spectrum, using large telescopes with efficient instrumentation located on superb sites. Technological advances and engineering constraints are nearing the point where we are recording as many photons arriving at a site as is possible. Major advances in the future will come from improving the quality of the site. The ultimate site is, of course, beyond the Earth’s atmosphere, such as on the Moon, but economic limitations prevent our exploiting this avenue to the degree that the scientific community desires. Here we describe an alternative, which offers many of the advantages of space for a fraction of the cost: the Antarctic Plateau.
Due to the wide bandgap and other key materials properties of 4H-SiC, SiC MOSFETs
offer performance advantages over competing Si-based power devices. For example,
SiC can more easily be used to fabricate MOSFETs with very high voltage ratings,
and with lower switching losses. Silicon carbide power MOSFET development has
progressed rapidly since the market release of Cree’s 1200V 4H-SiC
power MOSFET in 2011. This is due to continued advancements in SiC substrate
quality, epitaxial growth capabilities, and device processing. For example,
high-quality epitaxial growth of thick, low-doped SiC has enabled the
fabrication of SiC MOSFETs capable of blocking extremely high voltages (up to
15kV); while dopant control for thin highly-doped epitaxial layers has helped
enable low on-resistance 900V SiC MOSFET production. Device design and
processing improvements have resulted in lower MOSFET specific on-resistance for
each successive device generation. SiC MOSFETs have been shown to have a long
device lifetime, based on the results of accelerated lifetime testing, such as
high-temperature reverse-bias (HTRB) stress and time-dependent dielectric