2,723 research outputs found
Allozyme and mitochondrial DNA variability within the New Zealand damselfly genera Xanthocnemis, Austrolestes, and Ischnura (Odonata)
We collected larval damselflies from 17 sites in the North, South and Chatham Islands, and tested the hypotheses that: (1) genetic markers (e.g., allozymes, mtDNA) would successfully ¬discriminate taxa; and (2) the dispersal capabilities of adult damselflies would limit differentiation among locations. Four species from three genera were identified based on available taxonomic keys. Using 11 allozyme loci and the mitochondrial cytochrome c-oxidase subunit I (COI) gene, we confirmed that all taxa were clearly discernible. We found evidence for low to moderate differentiation among locations based on allozyme (mean FST = 0.09) and sequence (COI) divergence (<0.034). No obvious patterns with respect to geographic location were detected, although slight differences were found between New Zealand’s main islands (North Island, South Island) and the Chatham Islands for A. colensonis (sequence divergence 0.030–0.034). We also found limited intraspecific genetic variability based on allozyme data (Hexp < 0.06 in all cases). We conclude that levels of gene flow/dispersal on the main islands may have been sufficient to maintain the observed homogeneous population structure, and that genetic techniques, particularly the COI gene locus, will be a useful aid in future identifications
Evolution of Solid Processing Methods in Continuous Flow Technology: Reactive Extrusion
The frustrations of precipitation, fouling and blockages of liquid-based flow reactors are familiar to all researchers working with continuous flow equipment. There have been many innovative solutions to try and circumvent this issue. This short review will highlight the emerging technique of mechanochemistry and reactive extrusion as a continuous process that can directly work on solid (and liquid) materials and elicit chemical transformations
Targeting NaPi2b in ovarian cancer.
Novel biomarkers are needed to direct new treatments for ovarian cancer, a disease for which the standard of care remains heavily focused on platinum-based chemotherapy. Despite the success of PARP inhibitors, treatment options are limited, particularly in the platinum-resistant setting. NaPi2b is a cell surface sodium-dependent phosphate transporter that regulates phosphate homeostasis under normal physiological conditions and is a lineage marker that is expressed in select cancers, including ovarian, lung, thyroid, and breast cancers, with limited expression in normal tissues. Based on its increased expression in ovarian tumors, NaPi2b is a promising candidate to be studied as a biomarker for treatment and patient selection in ovarian cancer. In preclinical studies, the use of antibodies against NaPi2b showed that this protein can be exploited for tumor mapping and therapeutic targeting. Emerging data from phase 1 and 2 clinical trials in ovarian cancer have suggested that NaPi2b can be successfully detected in patient biopsy samples using immunohistochemistry, and the NaPi2b-targeting antibody-drug conjugate under evaluation appeared to elicit therapeutic responses. The aim of this review is to examine literature supporting NaPi2b as a novel biomarker for potential treatment and patient selection in ovarian cancer and to discuss the critical next steps and future analyses necessary to drive the study of this biomarker and therapeutic targeting forward
Effects of movement velocity and training frequency of resistance exercise on functional performance in older adults: a randomised controlled trial
Objectives: To investigate the effects that high-velocity, low-load (HVLL) and low-velocity, high-load (LVHL) resistance exercise, performed once or twice-weekly, have on indices of functional performance (primary outcome), maximal strength, and body composition (secondary outcomes) in older adults. Methods: In a randomised, controlled, multi-armed, parallel design, 54 moderately-highly active, but resistance exercise naïve older adults (aged 60–79 years), attended baseline and post-10-week intervention assessment sessions. Physical and functional assessments were completed, and predicted one-repetition maximums (1-RM) were obtained for eight exercises. Participants were then randomised into one of five conditions: HVLL once-weekly (HVLL1: n = 11) or twice-weekly (HVLL2: n = 11), LVHL once-weekly (LVHL1: n = 10) or twice-weekly (LVHL2: n = 11), no-exercise control condition (CON: n = 11). The HVLL conditions completed 3 sets of 14 repetitions at 40% 1-RM and the LVHL conditions, 3 sets of 7 repetitions at 80% 1-RM. In total, 50 participants completed all testing and were included in analyses. Results: Only LVHL2 improved 30-sec chair stand performance (p =.035; g = 0.89), arm curls (p =.011; g = 1.65) and grip-strength (p =.015; g = 0.34) compared to CON. LVHL2 improved maximal strength compared to CON for 7/8 exercises (p <.05). Whereas, LVHL1 and HVLL2 only improved seated row and chest press compared to CON (p <.05). Conclusion: Possibly due to the lower intensity nature of the HVLL conditions, LVHL, twice-weekly was most beneficial for improving functional performance and strength in moderately-highly active older adults. Therefore, we recommend that exercise professionals ensure resistance exercise sessions have sufficient intensity of effort and volume, in order to maximise functional performance and strength gains in older adults.
Impaired Orthostatic Blood Pressure Recovery is associated with Unexplained and Injurious Falls
Background/Objectives: Cardiovascular disorders are recognised as important modifiable risk factors for falls. However the association between falls and orthostatic hypotension (OH) remains ambivalent, particularly because of poor measurement methods of previous studies. Our goal was to determine for the first time to what extent OH (and variants) are risk factors for incident falls, unexplained falls (UF), injurious falls (IF) and syncope using dynamic blood pressure (BP) measurements in a population study. Design: Nationally Representative Longitudinal Cohort Study - The Irish Longitudinal Study on Ageing (TILDA) – wave 1 (2009-2011) with 2 year follow-up at wave 2 (2012-2013). Setting: Community dwelling adults. Participants: 4127 participants were randomly sampled from the population of older adults aged ≥50 years resident in Ireland. Measurements: Continuous BP recordings measured during active stands were analysed. OH and variants (initial OH and impaired orthostatic BP stabilisation OH(40)) were defined using dynamic BP measurements. Associations with the number of falls, UF, IF and syncope reported two years later were assessed using negative binomial and modified Poisson regression. Results: Participants had a mean age 61.5(8.2) years (54.2% female). OH(40) was associated with increased relative risk of UF (RR:1.52 95%CI:1.03-2.26). OH was associated with all-cause falls (IRR:1.40 95%CI:1.01-1.96), UF(RR:1.81 95%CI:1.06-3.09), and IF(RR:1.58 95%CI:1.12-2.24). IOH was not associated with any outcome. Conclusion: With the exception of initial orthostatic hypotension, beat-to-beat measures of impaired orthostatic BP recovery (delayed or incomplete stabilisation) are independent risk factors for future falls, unexplained falls, and injurious falls
Differential cell autonomous responses determine the outcome of coxsackievirus infections in murine pancreatic α and β cells
This is the final version of the article. Available from eLife Sciences Publications via the DOI in this record.Type 1 diabetes (T1D) is an autoimmune disease caused by loss of pancreatic β cells via apoptosis while neighboring α cells are preserved. Viral infections by coxsackieviruses (CVB) may contribute to trigger autoimmunity in T1D. Cellular permissiveness to viral infection is modulated by innate antiviral responses, which vary among different cell types. We presently describe that global gene expression is similar in cytokine-treated and virus-infected human islet cells, with up-regulation of gene networks involved in cell autonomous immune responses. Comparison between the responses of rat pancreatic α and β cells to infection by CVB5 and 4 indicate that α cells trigger a more efficient antiviral response than β cells, including higher basal and induced expression of STAT1-regulated genes, and are thus better able to clear viral infections than β cells. These differences may explain why pancreatic β cells, but not α cells, are targeted by an autoimmune response during T1D.Fonds De La Recherche Scientifique – FNRS: FNRS- F 5/4/5.MCF/KP. Project de secherche (PDR) T.0036.13; European Commission (EC): Projects Naimit and BetaBat, in the Framework Programme 7 of the European Community; Federation Wallonie- Bruxelles: the Communaute Franc¸ aise de BelgiqueActions de Recherche Concertees (ARC); Fonds De La Recherche Scientifique – FNRS: FNRS post-doctoral fellowship; Governo Brasil: PDE/CSF Pos-Doutorado no Exterior; Juvenile Diabetes Research Foundation International (JDRF): JDRF Career Development Award; European Commission (EC): European Union’s Seventh Framework Programme [FP7/2007-2013] under grant agreement 261441 PEVNE
Fragments of the earliest land plants
The earliest fossil evidence for land plants comes from microscopic dispersed spores. These microfossils are abundant and widely distributed in sediments, and the earliest generally accepted reports are from rocks of mid-Ordovician age (Llanvirn, 475 million years ago). Although distribution, morphology and ultrastructure of the spores indicate that they are derived from terrestrial plants, possibly early relatives of the bryophytes, this interpretation remains controversial as there is little in the way of direct evidence for the parent plants. An additional complicating factor is that there is a significant hiatus between the appearance of the first dispersed spores and fossils of relatively complete land plants (megafossils): spores predate the earliest megafossils (Late Silurian, 425 million year ago) by some 50 million years. Here we report the description of spore-containing plant fragments from Ordovician rocks of Oman. These fossils provide direct evidence for the nature of the spore-producing plants. They confirm that the earliest spores developed in large numbers within sporangia, providing strong evidence that they are the fossilized remains of bona fide land plants. Furthermore, analysis of spore wall ultrastructure supports liverwort affinities
Analysis of clinical uncertainties by health professionals and patients: an example from mental health
<p>Abstract</p> <p>Background</p> <p>The first step in practising Evidence Based Medicine (EBM) has been described as translating clinical uncertainty into a structured and focused clinical question that can be used to search the literature to ascertain or refute that uncertainty. In this study we focus on questions about treatments for schizophrenia posed by mental health professionals and patients to gain a deeper understanding about types of questions asked naturally, and whether they can be reformulated into structured and focused clinical questions.</p> <p>Methods</p> <p>From a survey of uncertainties about the treatment of schizophrenia we describe, categorise and analyse the type of questions asked by mental health professionals and patients about treatment uncertainties for schizophrenia. We explore the value of mapping from an unstructured to a structured framework, test inter-rater reliability for this task, develop a linguistic taxonomy, and cross tabulate that taxonomy with elements of a well structured clinical question.</p> <p>Results</p> <p>Few of the 78 Patients and 161 clinicians spontaneously asked well structured queries about treatment uncertainties for schizophrenia. Uncertainties were most commonly about drug treatments (45.3% of clinicians and 41% of patients), psychological therapies (19.9% of clinicians and 9% of patients) or were unclassifiable.(11.8% of clinicians and 16.7% of patients). Few naturally asked questions could be classified using the well structured and focused clinical question format (i.e. PICO format). A simple linguistic taxonomy better described the types of questions people naturally ask.</p> <p>Conclusion</p> <p>People do not spontaneously ask well structured clinical questions. Other taxonomies may better capture the nature of questions. However, access to EBM resources is greatly facilitated by framing enquiries in the language of EBM, such as posing queries in PICO format. People do not naturally do this. It may be preferable to identify a way of searching the literature that more closely matches the way people naturally ask questions if access to information about treatments are to be made more broadly available.</p
Easily retrievable objects among the NEO population
Asteroids and comets are of strategic importance for science in an effort to understand the formation, evolution and composition of the Solar System. Near-Earth Objects (NEOs) are of particular interest because of their accessibility from Earth, but also because of their speculated wealth of material resources. The exploitation of these resources has long been discussed as a means to lower the cost of future space endeavours. In this paper, we consider the currently known NEO population and define a family of so-called Easily Retrievable Objects (EROs), objects that can be transported from accessible heliocentric orbits into the Earth’s neighbourhood at affordable costs. The asteroid retrieval transfers are sought from the continuum of low energy transfers enabled by the dynamics of invariant manifolds; specifically, the retrieval transfers target planar, vertical Lyapunov and halo orbit families associated with the collinear equilibrium points of the Sun-Earth Circular Restricted Three Body problem. The judicious use of these dynamical features provides the best opportunity to find extremely low energy Earth transfers for asteroid material. A catalogue of asteroid retrieval candidates is then presented. Despite the highly incomplete census of very small asteroids, the ERO catalogue can already be populated with 12 different objects retrievable with less than 500 m/s of Δv. Moreover, the approach proposed represents a robust search and ranking methodology for future retrieval candidates that can be automatically applied to the growing survey of NEOs
Association of treatment satisfaction and psychopathological sub-syndromes among involuntary patients with psychotic disorders
Publisher's version: http://www.springerlink.com/content/rx24036274667t10
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