Hemiparasitic plant impacts animal and plant communities across four trophic levels

1.Understanding the impact of species on community structure is a fundamental question in ecology. There is a growing body of evidence that suggests that both sub-dominant species and parasites can have a disproportionately large impact. 2.Here we report the impacts of an organism that is both subdominant and parasitic, the hemiparasite Rhinanthus minor. Whilst the impact of parasitic angiosperms on their hosts and, to a lesser degree, co-existing plant species, have been well characterized, much less is known about their impacts on higher trophic levels. 3.We experimentally manipulated field densities of the hemiparasite Rhinanthus minor in a species rich grassland, comparing the plant and invertebrate communities in plots where it was removed, at natural densities or at enhanced densities. 4.Plots with natural and enhanced densities of R. minor had lower plant biomass than plots without the hemiparasite, but enhanced densities almost doubled the abundance of invertebrates within the plots across all trophic levels, with effects evident in herbivores, predators and detritivores. 5.The hemiparasite R. minor, despite being a sub-dominant and transient component within plant communities that it inhabits, has profound effects on four different trophic levels. These effects persist beyond the life of the hemiparasite, emphasizing its role as a keystone species in grassland communitie

A Comparison Between the Theoretical and Measured Longitudinal Stability Characteristics of an Airplane

This report covers an investigation of the application of the theory of dynamic longitudinal stability, based on the assumption of small oscillations, to oscillations an airplane is likely to undergo in flight. The investigation was conducted with a small parasol monoplane for the fixed-stick condition. The period and damping of longitudinal oscillations were determined by direct measurements of oscillations in flight and also by calculation in which the factors that enter the theoretical stability equation were determined in flight. A comparison of the above-mentioned characteristics obtained by these two methods indicates that the theory is applicable to the conditions encountered in flight

Defective repair of cisplatin-induced DNA damage caused by reduced XPA protein in testicular germ cell tumours

AbstractMetastatic cancer in adults usually has a fatal outcome. In contrast, advanced testicular germ cell tumours are cured in over 80% of patients using cisplatin-based combination chemotherapy [1]. An understanding of why these cells are sensitive to chemotherapeutic drugs is likely to have implications for the treatment of other types of cancer. Earlier measurements indicate that testis tumour cells are hypersensitive to cisplatin and have a low capacity to remove cisplatin-induced DNA damage from the genome [2,3]. We have investigated the nucleotide excision repair (NER) capacity of extracts from the well-defined 833K and GCT27 human testis tumour cell lines. Both had a reduced ability to carry out the incision steps of NER in comparison with extracts from known repair-proficient cells. Immunoblotting revealed that the testis tumour cells had normal amounts of most NER proteins, but low levels of the xeroderma pigmentosum group A protein (XPA) and the ERCC1–XPF endonuclease complex. Addition of XPA specifically conferred full NER capacity on the testis tumour extracts. These results show that a low XPA level in the testis tumour cell lines is sufficient to explain their poor ability to remove cisplatin adducts from DNA and might be a major reason for the high cisplatin sensitivity of testis tumours. Targeted inhibition of XPA could sensitise other types of cells and tumours to cisplatin and broaden the usefulness of this chemotherapeutic agent

Photogrammetry and ballistic analysis of a high-flying projectile in the STS-124 space shuttle launch

A method combining photogrammetry with ballistic analysis is demonstrated to identify flying debris in a rocket launch environment. Debris traveling near the STS-124 Space Shuttle was captured on cameras viewing the launch pad within the first few seconds after launch. One particular piece of debris caught the attention of investigators studying the release of flame trench fire bricks because its high trajectory could indicate a flight risk to the Space Shuttle. Digitized images from two pad perimeter high-speed 16-mm film cameras were processed using photogrammetry software based on a multi-parameter optimization technique. Reference points in the image were found from 3D CAD models of the launch pad and from surveyed points on the pad. The three-dimensional reference points were matched to the equivalent two-dimensional camera projections by optimizing the camera model parameters using a gradient search optimization technique. Using this method of solving the triangulation problem, the xyz position of the object's path relative to the reference point coordinate system was found for every set of synchronized images. This trajectory was then compared to a predicted trajectory while performing regression analysis on the ballistic coefficient and other parameters. This identified, with a high degree of confidence, the object's material density and thus its probable origin within the launch pad environment. Future extensions of this methodology may make it possible to diagnose the underlying causes of debris-releasing events in near-real time, thus improving flight safety.Comment: 26 pages, 11 figures, 3 table

Coarse-grained meandering distributive fluvial system of the Basal Cedar mountain formation, U.S.A.

Funding Information: We thank the following for reviews of this manuscript: Associate Editor Tobi Payenberg, Matt Joeckel, two anonymous reviewers, and John Southard. This work was funded by the SAFARI group. We are deeply grateful to Joe Phillips, Sean Kelly, James Mullins, Ryan King, and Jostein Myking Kjærefjord for help in the field.Peer reviewedPostprin

The evolution and storage of primitive melts in the Eastern Volcanic Zone of Iceland: the 10 ka Grímsvötn tephra series (i.e. the Saksunarvatn ash)

Major, trace and volatile elements were measured in a suite of primitive macrocrysts and melt inclusions from the thickest layer of the 10 ka Grímsvötn tephra series (i.e. Saksunarvatn ash) at Lake Hvítárvatn in central Iceland. In the absence of primitive tholeiitic eruptions (MgO > 7 wt%) within the Eastern Volcanic Zone (EVZ) of Iceland, these crystal and inclusion compositions provide an important insight into magmatic processes in this volcanically productive region. Matrix glass compositions show strong similarities with glass compositions from the AD 1783–1784 Laki eruption, confirming the affinity of the tephra series with the Grímsvötn volcanic system. Macrocrysts can be divided into a primitive assemblage of zoned macrocryst cores (An78–An92, Mg#cpx = 82–87, Fo79.5–Fo87) and an evolved assemblage consisting of unzoned macrocrysts and the rims of zoned macrocrysts (An60–An68, Mg#cpx = 71–78, Fo70–Fo76). Although the evolved assemblage is close to being in equilibrium with the matrix glass, trace element disequilibrium between primitive and evolved assemblages indicates that they were derived from different distributions of mantle melt compositions. Juxtaposition of disequilibrium assemblages probably occurred during disaggregation of incompatible trace element-depleted mushes (mean La/Ybmelt = 2.1) into aphyric and incompatible trace element-enriched liquids (La/Ybmelt = 3.6) shortly before the growth of the evolved macrocryst assemblage. Post-entrapment modification of plagioclase-hosted melt inclusions has been minimal and high-Mg# inclusions record differentiation and mixing of compositionally variable mantle melts that are amongst the most primitive liquids known from the EVZ. Coupled high-field strength element (HFSE) depletion and incompatible trace element enrichment in a subset of primitive plagioclase-hosted melt inclusions can be accounted for by inclusion formation following plagioclase dissolution driven by interaction with plagioclase-undersaturated melts. Thermobarometric calculations indicate that final crystal–melt equilibration within the evolved assemblage occurred at ~1140 °C and 0.0–1.5 kbar. Considering the large volume of the erupted tephra and textural evidence for rapid crystallisation of the evolved assemblage, 0.0–1.5 kbar is considered unlikely to represent a pressure of long-term magma accumulation and storage. Multiple thermometers indicate that the primitive assemblage crystallised at high temperatures of 1240–1300 °C. Different barometers, however, return markedly different crystallisation depth estimates. Raw clinopyroxene–melt pressures of 5.5–7.5 kbar conflict with apparent melt inclusion entrapment pressures of 1.4 kbar. After applying a correction derived from published experimental data, clinopyroxene–melt equilibria return mid-crustal pressures of 4 ± 1.5 kbar, which are consistent with pressures estimated from the major element content of primitive melt inclusions. Long-term storage of primitive magmas in the mid-crust implies that low CO2 concentrations measured in primitive plagioclase-hosted inclusions (262–800 ppm) result from post-entrapment CO2 loss during transport through the shallow crust. In order to reconstruct basaltic plumbing system geometries from petrological data with greater confidence, mineral–melt equilibrium models require refinement at pressures of magma storage in Iceland. Further basalt phase equilibria experiments are thus needed within the crucial 1–7 kbar range

Adoption and Use of Electronic Health Records by Rural Health Clinics: Results of a National Survey [Working Paper]

Rural Health Clinics (RHCs) are a vital source of primary care services with more than 4,000 clinics serving rural communities. Relatively little is known about the extent to which RHCs have adopted and are using electronic health records (EHRs) to support clinical services. Because EHR adoption is an essential element for inclusion in accountable care organizations, patient centered medical homes, and health plan provider networks offered on state and national health insurance marketplaces, EHR implementation will be increasingly important to RHCs if they are to remain competitive participants in the evolving healthcare market. Key Findings: Nearly 72 percent of Rural Health Clinics (RHCs) have an operational electronic health record (EHR), with 63 percent indicating use by 90 percent or more of their staff. Slightly over 17 percent of RHCs without an EHR plan to implement one within six months, and 27 percent plan to do so within seven to twelve months. Common barriers to EHR implementation include acquisition and maintenance costs (72 percent), lack of capital (51 percent), and concerns about productivity and income loss during implementation (45 percent). RHCs continue to lag on some meaningful use measures, but perform well on measures related to clinical care and patient management. With Regional Extension Centers facing the loss of federal funding it is important to identify additional resources to assist RHCs in maximizing EHR adoption and use

Rural Health Clinic Readiness for Patient-Centered Medical Home Recognition: Preparing for the Evolving Healthcare Marketplace [Working Paper]

The patient-centered medical home (PCMH) model reaffirms traditional primary care values including continuity of care, connection with an identified personal clinician, provision of same day- and after-hours access, and positions providers to participate in accountable care and other financing and delivery system models. However, little is known about the readiness of the over 4,000 Rural Health Clinics (RHCs) to meet the PCMH Recognition standards established by the National Council for Quality Assurance (NCQA). The authors present findings from a survey of RHCs that examined their capacity to meet the NCQA PCMH requirements, and discuss the implications of the findings for efforts to support RHC capacity development. Key Findings: Based on their performance on the “must pass” elements and related key factors, Rural Health Clinics (RHCs) are likely to have difficulties gaining National Center for Quality Assurance’s (NCQA) Patient-Centered Medical Home (PCMH) Recognition. RHCs perform best on standards related to recording demographic information and managing clinical activities, particularly for those using an electronic health record. RHCs perform less well on improving access to and continuity of services, supporting patient self-management skills and shared decision-making, implementing continuous quality improvement systems, and building practice teams. RHCs are likely to need substantial technical assistance targeting clinical and operational performance to gain NCQA PCMH Recognition

Meaningful Use of Electronic Health Record by Rural Health Clinics [Policy Brief]

Little information is available on the rate of Electronic Health Record (EHR) adoption by Rural Health Clinics. (RHCs). This study was conducted to identify the rates of EHR adoption among a national random sample of RHCs and the extent to which RHCs that have adopted an EHR are likely to achieve Stage 1 meaningful use. To achieve Stage 1 meaningful use and qualify for meaningful use incentive payments, eligible health professionals must, at a minimum, meet CMS defined criteria for the required 14 core measures. Fifty-nine percent of RHCs report having an EHR, and independent RHCs were more likely than hospital-based RHCs to have an EHR. Common barriers to EHR adoption by RCHs include acquisition and maintenance costs, lack of capital, and potential productivity or income loss during transition