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This new edition of a foundational text presents a contemporary review of cladistics, as applied to biological classification. It provides a comprehensive account of the past 50 years of discussion on the relationship between classification, phylogeny and evolution. It covers cladistics in the era of molecular data, detailing new advances and ideas that have emerged over the last 25 years. Written in an accessible style by internationally renowned authors in the field, readers are straightforwardly guided through fundamental principles and terminology. Simple worked examples and easy-to-understand diagrams also help readers navigate complex problems that have perplexed scientists for centuries. This practical guide is an essential addition for advanced undergraduates, postgraduates and researchers in taxonomy, systematics, comparative biology, evolutionary biology and molecular biology.
We present the analysis of global sympagic primary production (PP) from 300 years of pre-industrial and historical simulations of the E3SMv1.1-BGC model. The model includes a novel, eight-element sea ice biogeochemical component, MPAS-Seaice zbgc, which is resolved in three spatial dimensions and uses a vertical transport scheme based on internal brine dynamics. Modeled ice algal chlorophyll-a concentrations and column-integrated values are broadly consistent with observations, though chl-a profile fractions indicate that upper ice communities of the Southern Ocean are underestimated. Simulations of polar integrated sea ice PP support the lower bound in published estimates for both polar regions with mean Arctic values of 7.5 and 15.5 TgC/a in the Southern Ocean. However, comparisons of the polar climate state with observations, using a maximal bound for ice algal growth rates, suggest that the Arctic lower bound is a significant underestimation driven by biases in ocean surface nitrate, and that correction of these biases supports as much as 60.7 TgC/a of net Arctic PP. Simulated Southern Ocean sympagic PP is predominantly light-limited, and regional patterns, particularly in the coastal high production band, are found to be negatively correlated with snow thickness.
Electrochemical capacitors featuring a modified acetonitrile (AN) electrolyte and a binder-free, activated carbon fabric electrode material were assembled and tested at <−40 °C. The melting point of the electrolyte was depressed relative to the standard pure AN solvent through the use of a methyl formate cosolvent, to enable operation at temperatures lower than the rated limit of typical commercial cells (−40 °C). Based on earlier electrolyte formulation studies, a 1:1 ratio of methyl formate to AN (by volume) was selected, to maximize freezing point depression while maintaining a sufficient salt solubility. The salt spiro-(1,1′)-bipyrrolidinium tetrafluoroborate was used, based on its improved conductivity at low temperatures, relative to linear alkyl ammonium salts. The carbon fabric electrode supported a relatively high rate capability at temperatures as low as −65 °C with a modest increase in cell resistance at this reduced temperature. The capacitance was only weakly dependent on temperature, with a specific capacitance of ∼110 F/g.
The risk of endocarditis varies with CHD complexity and the presence of prosthetic valves. The purpose of the study was therefore to describe incidence and outcomes of prosthetic valve endocarditis in adults with repair tetralogy of Fallot.
Retrospective review of adult tetralogy of Fallot patients who underwent prosthetic valve implantation, 1990–2017. We defined prosthetic valve endocarditis-related complications as prosthetic valve dysfunction, perivalvular extension of infection such abscess/aneurysm/fistula, heart block, pulmonary/systemic embolic events, recurrent endocarditis, and death due to sepsis.
A total of 338 patients (age: 37 ± 15 years) received 352 prosthetic valves (pulmonary [n = 308, 88%], tricuspid [n = 13, 4%], mitral [n = 9, 3%], and aortic position [n = 22, 6%]). The annual incidence of prosthetic valve endocarditis was 0.4%. There were 12 prosthetic valve endocarditis-related complications in six patients, and these complications were prosthetic valve dysfunction (n = 4), systemic/pulmonary embolic events (n = 2), heart block (n = 1), aortic root abscess (n = 1), recurrent endocarditis (n = 2), and death due to sepsis (n = 1). Three (50%) patients required surgery at 2 days, 6 weeks, and 23 weeks from the time of prosthetic valve endocarditis diagnosis. Altogether three of the six (50%) patients died, and one of these deaths was due to sepsis.
The incidence, complication rate, and outcomes of prosthetic valve endocarditis in tetralogy of Fallot patients underscore some of the risks of having a prosthetic valve. It is important to educate the patients on the need for early presentation if they develop systemic symptoms, have a high index of suspicion for prosthetic valve endocarditis, and adopt a multi-disciplinary care approach in this high-risk population.
The Murchison Widefield Array (MWA) is an open access telescope dedicated to studying the low-frequency (80–300 MHz) southern sky. Since beginning operations in mid-2013, the MWA has opened a new observational window in the southern hemisphere enabling many science areas. The driving science objectives of the original design were to observe 21 cm radiation from the Epoch of Reionisation (EoR), explore the radio time domain, perform Galactic and extragalactic surveys, and monitor solar, heliospheric, and ionospheric phenomena. All together
programs recorded 20 000 h producing 146 papers to date. In 2016, the telescope underwent a major upgrade resulting in alternating compact and extended configurations. Other upgrades, including digital back-ends and a rapid-response triggering system, have been developed since the original array was commissioned. In this paper, we review the major results from the prior operation of the MWA and then discuss the new science paths enabled by the improved capabilities. We group these science opportunities by the four original science themes but also include ideas for directions outside these categories.
In this chapter, the authors discuss the issues related to post-operative neonatal apnea with an example of an infant hernia repair. Neonatal apnea, its etiology and associated risk factors is reviewed. The use of infant spinal anesthesia versus general anesthesia and its relationship to neonatal post-operative apnea is discussed.
In this article, we review some of the recent developments in instrumentation and methods that have led to the rise of cryo-electron microscopy (cryo-EM) in the life sciences community, and consider how researchers in the materials community might benefit from these advances. Transmission electron microscopy (TEM) is compared with scanning transmission electron microscopy (STEM) for cryogenic imaging in both biological and materials science applications. We discuss the developments in detector technologies that have in part powered the development of cryo-EM and anticipate exciting areas for productive overlap between life science and materials science cryo-EM applications.
Multi- and hyperspectral sensors in the visible to short-wave infrared (0.4–2.5 μm) are sensitive to spectral features caused by electronic charge transfer and transition metal crystal field band as well as molecular overtone absorptions. This chapter reviews several processing techniques used to map materials on planetary surfaces based on their reflectance spectra in this spectral region. Techniques that are reviewed include spectral matching in the form of spectral angle and spectral information divergence, linear and nonlinear spectral unmixing, partial unmixing/matched filters, and machine learning approaches in the form of self-organizing maps, neural network classification, and support vector machines.
Multispectral imaging – the acquisition of spatially contiguous imaging data in a modest number (~3–16) of spectral bandpasses – has proven to be a powerful technique for augmenting panchromatic imaging observations on Mars focused on geologic and/or atmospheric context. Specifically, multispectral imaging using modern digital CCD photodetectors and narrowband filters in the 400–1100 nm wavelength region on the Mars Pathfinder, Mars Exploration Rover, Phoenix, and Mars Science Laboratory missions has provided new information on the composition and mineralogy of fine-grained regolith components (dust, soils, sand, spherules, coatings), rocky surface regions (cobbles, pebbles, boulders, outcrops, and fracture-filling veins), meteorites, and airborne dust and other aerosols. Here we review recent scientific results from Mars surface-based multispectral imaging investigations, including the ways that these observations have been used in concert with other kinds of measurements to enhance the overall scientific return from Mars surface missions.
The near-infrared reflectance spectra of Pluto and its satellites are rich with diagnostic absorption bands of ices of CH4, N2, CO, H2O, and an incompletely identified ammonia-bearing molecule. Following years of investigation of the spectra of Pluto and Charon with ground-based telescopes, NASA’s New Horizons spacecraft obtained spectral maps of these bodies and three small satellites on its passage through the system on July 14, 2015, showing the distribution of these ices, as well as a colored, non-ice component. Spectral modeling mapped the distribution of the various ices and showed their abundance and mixing details in relationship to regions of differing surface elevation, albedo, and geologic structure. Additionally, owing to their greatly different degrees of volatility, the ices of Pluto are distributed in patterns responsive to Pluto’s climatic changes on both short and long terms. The surface of Charon is dominated spectrally by H2O ice with one or more ammoniated compounds, and three of the four very small satellites show both H2O ice and the ammonia signature.
Scientific quality and feasibility are part of ethics review by Institutional Review Boards (IRBs). Scientific Review Committees (SRCs) were proposed to facilitate this assessment by the Clinical and Translational Science Award (CTSA) SRC Consensus Group. This study assessed SRC feasibility and impact at CTSA-affiliated academic health centers (AHCs).
SRC implementation at 10 AHCs was assessed pre/post-intervention using quantitative and qualitative methods. Pre-intervention, four AHCs had no SRC, and six had at least one SRC needing modifications to better align with Consensus Group recommendations.
Facilitators of successful SRC implementation included broad-based communication, an external motivator, senior-level support, and committed SRC reviewers. Barriers included limited resources and staffing, variable local mandates, limited SRC authority, lack of anticipated benefit, and operational challenges. Research protocol quality did not differ significantly between study periods, but respondents suggested positive effects. During intervention, median total review duration did not lengthen for the 40% of protocols approved within 3 weeks. For the 60% under review after 3 weeks, review was lengthened primarily due to longer IRB review for SRC-reviewed protocols. Site interviews recommended designing locally effective SRC processes, building buy-in by communication or by mandate, allowing time for planning and sharing best practices, and connecting SRC and IRB procedures.
The CTSA SRC Consensus Group recommendations appear feasible. Although not conclusive in this relatively short initial implementation, sites perceived positive impact by SRCs on study quality. Optimal benefit will require local or federal mandate for implementation, adapting processes to local contexts, and employing SRC stipulations.
The Murchison Widefield Array (MWA) is an electronically steered low-frequency (<300 MHz) radio interferometer, with a ‘slew’ time less than 8 s. Low-frequency (∼100 MHz) radio telescopes are ideally suited for rapid response follow-up of transients due to their large field of view, the inverted spectrum of coherent emission, and the fact that the dispersion delay between a 1 GHz and 100 MHz pulse is on the order of 1–10 min for dispersion measures of 100–2000 pc/cm3. The MWA has previously been used to provide fast follow-up for transient events including gamma-ray bursts (GRBs), fast radio bursts (FRBs), and gravitational waves, using systems that respond to gamma-ray coordinates network packet-based notifications. We describe a system for automatically triggering MWA observations of such events, based on Virtual Observatory Event standard triggers, which is more flexible, capable, and accurate than previous systems. The system can respond to external multi-messenger triggers, which makes it well-suited to searching for prompt coherent radio emission from GRBs, the study of FRBs and gravitational waves, single pulse studies of pulsars, and rapid follow-up of high-energy superflares from flare stars. The new triggering system has the capability to trigger observations in both the regular correlator mode (limited to ≥0.5 s integrations) and using the Voltage Capture System (VCS, 0.1 ms integration) of the MWA and represents a new mode of operation for the MWA. The upgraded standard correlator triggering capability has been in use since MWA observing semester 2018B (July–Dec 2018), and the VCS and buffered mode triggers will become available for observing in a future semester.
Clonal Mycobacterium mucogenicum isolates (determined by molecular typing) were recovered from 19 bronchoscopic specimens from 15 patients. None of these patients had evidence of mycobacterial infection. Laboratory culture materials and bronchoscopes were negative for Mycobacteria. This pseudo-outbreak was caused by contaminated ice used to provide bronchoscopic lavage. Control was achieved by transitioning to sterile ice.
The WHO African region is characterised by the largest infectious disease burden in the world. We conducted a retrospective descriptive analysis using records of all infectious disease outbreaks formally reported to the WHO in 2018 by Member States of the African region. We analysed the spatio-temporal distribution, the notification delay as well as the morbidity and mortality associated with these outbreaks. In 2018, 96 new disease outbreaks were reported across 36 of the 47 Member States. The most commonly reported disease outbreak was cholera which accounted for 20.8% (n = 20) of all events, followed by measles (n = 11, 11.5%) and Yellow fever (n = 7, 7.3%). About a quarter of the outbreaks (n = 23) were reported following signals detected through media monitoring conducted at the WHO regional office for Africa. The median delay between the disease onset and WHO notification was 16 days (range: 0–184). A total of 107 167 people were directly affected including 1221 deaths (mean case fatality ratio (CFR): 1.14% (95% confidence interval (CI) 1.07%–1.20%)). The highest CFR was observed for diseases targeted for eradication or elimination: 3.45% (95% CI 0.89%–10.45%). The African region remains prone to outbreaks of infectious diseases. It is therefore critical that Member States improve their capacities to rapidly detect, report and respond to public health events.
To assess the impact of a newly developed Central-Line Insertion Site Assessment (CLISA) score on the incidence of local inflammation or infection for CLABSI prevention.
A pre- and postintervention, quasi-experimental quality improvement study.
Setting and participants:
Adult inpatients with central venous catheters (CVCs) hospitalized in an intensive care unit or oncology ward at a large academic medical center.
We evaluated CLISA score impact on insertion site inflammation and infection (CLISA score of 2 or 3) incidence in the baseline period (June 2014–January 2015) and the intervention period (April 2015–October 2017) using interrupted times series and generalized linear mixed-effects multivariable analyses. These were run separately for days-to-line removal from identification of a CLISA score of 2 or 3. CLISA score interrater reliability and photo quiz results were evaluated.
Among 6,957 CVCs assessed 40,846 times, percentage of lines with CLISA score of 2 or 3 in the baseline and intervention periods decreased by 78.2% (from 22.0% to 4.7%), with a significant immediate decrease in the time-series analysis (P < .001). According to the multivariable regression, the intervention was associated with lower percentage of lines with a CLISA score of 2 or 3, after adjusting for age, gender, CVC body location, and hospital unit (odds ratio, 0.15; 95% confidence interval, 0.06–0.34; P < .001). According to the multivariate regression, days to removal of lines with CLISA score of 2 or 3 was 3.19 days faster after the intervention (P < .001). Also, line dwell time decreased 37.1% from a mean of 14 days (standard deviation [SD], 10.6) to 8.8 days (SD, 9.0) (P < .001). Device utilization ratios decreased 9% from 0.64 (SD, 0.08) to 0.58 (SD, 0.06) (P = .039).
The CLISA score creates a common language for assessing line infection risk and successfully promotes high compliance with best practices in timely line removal.
Herbicides have been a primary means of managing undesirable brush on grazing lands across the southwestern United States for decades. Continued encroachment of honey mesquite and huisache on grazing lands warrants evaluation of treatment life and economics of current and experimental treatments. Treatment life is defined as the time between treatment application and when canopy cover of undesirable brush returns to a competitive level with native forage grasses (i.e., 25% canopy cover for mesquite and 30% canopy cover for huisache). Treatment life of industry-standard herbicides was compared with that of aminocyclopyrachlor plus triclopyr amine (ACP+T) from 10 broadcast-applied honey mesquite and five broadcast-applied huisache trials established from 2007 through 2013 across Texas. On average, the treatment life of industry standard treatments (IST) for huisache was 3 yr. In comparison, huisache canopy cover was only 2.5% in plots treated with ACP+T 3 yr after treatment. The average treatment life of IST for honey mesquite was 8.6 yr, whereas plots treated with ACP+T had just 2% mesquite canopy cover at that time. Improved treatment life of ACP+T compared with IST life was due to higher mortality resulting in more consistent brush canopy reduction. The net present values (NPVs) of ACP+T and IST for both huisache and mesquite were similar until the treatment life of the IST application was reached (3 yr for huisache and 8.6 yr for honey mesquite). At that point, NPVs of the programs diverged as a result of brush competition with desirable forage grasses and additional input costs associated with theoretical follow-up IST necessary to maintain optimum livestock forage production. The ACP+T treatments did not warrant a sequential application over the 12-yr analysis for huisache or 20-yr analysis for honey mesquite that this research covered. These results indicate ACP+T provides cost-effective, long-term control of honey mesquite and huisache.
TwinsUK is the largest cohort of community-dwelling adult twins in the UK. The registry comprises over 14,000 volunteer twins (14,838 including mixed, single and triplets); it is predominantly female (82%) and middle-aged (mean age 59). In addition, over 1800 parents and siblings of twins are registered volunteers. During the last 27 years, TwinsUK has collected numerous questionnaire responses, physical/cognitive measures and biological measures on over 8500 subjects. Data were collected alongside four comprehensive phenotyping clinical visits to the Department of Twin Research and Genetic Epidemiology, King’s College London. Such collection methods have resulted in very detailed longitudinal clinical, biochemical, behavioral, dietary and socioeconomic cohort characterization; it provides a multidisciplinary platform for the study of complex disease during the adult life course, including the process of healthy aging. The major strength of TwinsUK is the availability of several ‘omic’ technologies for a range of sample types from participants, which includes genomewide scans of single-nucleotide variants, next-generation sequencing, metabolomic profiles, microbiomics, exome sequencing, epigenetic markers, gene expression arrays, RNA sequencing and telomere length measures. TwinsUK facilitates and actively encourages sharing the ‘TwinsUK’ resource with the scientific community — interested researchers may request data via the TwinsUK website (http://twinsuk.ac.uk/resources-for-researchers/access-our-data/) for their own use or future collaboration with the study team. In addition, further cohort data collection is planned via the Wellcome Open Research gateway (https://wellcomeopenresearch.org/gateways). The current article presents an up-to-date report on the application of technological advances, new study procedures in the cohort and future direction of TwinsUK.