502 research outputs found
The story of Wellesley, Massachusetts, for fifth grade children
Thesis (Ed.M.)--Boston Universit
An NADPH-Dependent Genetic Switch Regulates Plant Infection by the Rice Blast Fungus
To cause rice blast disease, the fungus Magnaporthe oryzae breaches the tough outer cuticle of the rice leaf by using specialized infection structures called appressoria. These cells allow the fungus to invade the host plant and proliferate rapidly within leaf tissue. Here, we show that a unique NADPH-dependent genetic switch regulates plant infection in response to the changing nutritional and redox conditions encountered by the pathogen. The biosynthetic enzyme trehalose-6-phosphate synthase (Tps1) integrates control of glucose-6-phosphate metabolism and nitrogen source utilization by regulating the oxidative pentose phosphate pathway, the generation of NADPH, and the activity of nitrate reductase. We report that Tps1 directly binds to NADPH and, thereby, regulates a set of related transcriptional corepressors, comprising three proteins, Nmr1, Nmr2, and Nmr3, which can each bind NADP. Targeted deletion of any of the Nmr-encoding genes partially suppresses the nonpathogenic phenotype of a Δtps1 mutant. Tps1-dependentNmr corepressors control the expression of a set of virulence-associated genes that are derepressed during appressorium-mediated plant infection. When considered together, these results suggest that initiation of rice blast disease by M. oryzae requires a regulatory mechanism involving an NADPH sensor protein, Tps1, a set of NADP-dependent transcriptional corepressors, and the nonconsuming interconversion ofNADPHandNADPacting as signal transducer
Comparisons of trace constituents from ground stations and the DC-8 aircraft during PEM-West B
Chemical data from ground stations in Asia and the North Pacific are compared with data from the DC-8 aircraft collected during the Pacific Exploratory Measurements in the Western Pacific Ocean (PEM-West B) mission. Ground station sampling took place on Hong Kong, Taiwan, Okinawa, and Cheju; and at three Pacific islands, Shemya, Midway, and Oahu. Aircraft samples were collected during 19 flights, most over the western North Pacific. Aluminum was used as an indicator of mineral aerosol, and even though the aircraft did sample Asian dust, strong dust storms were not encountered. The frequency distribution for non-sea-salt sulfate (nss SO4=) in the aircraft samples was bimodal: the higher concentration mode (∼1 μg m−3) evidently originated from pollution or, less likely, from volcanic sources, while the lower mode, with a peak at 0.040 μg m−3, probably was a product of biogenic emissions. In addition, the concentrations of aerosol sulfate varied strongly in the vertical: arithmetic mean SO4=concentrations above 5000 m ( = 0.21±0.69 μg m−3) were substantially lower than those below ( = 1.07±0.87 μg m−3), suggesting the predominance of the surface sources. Several samples collected in the stratosphere exhibited elevated SO4=, however, probably as a result of emissions from Mount Pinatubo. During some boundary layer legs on the DC-8, the concentrations of CO and O3 were comparable to those of clean marine air, but during other legs, several chemically distinct air masses were sampled, including polluted air in which O3was photochemically produced. In general, the continental outflow sampled from the aircraft was substantially diluted with respect to what was observed at the ground stations. Higher concentrations of aerosol species, O3, and CO at the Hong Kong ground station relative to the aircraft suggest that much of the continental outflow from southeastern Asia occurs in the lower troposphere, and extensive long-range transport out of this part of Asia is not expected. In comparison, materials emitted farther to the north apparently are more susceptible to long-range transport
Hyperexcitability in young iPSC-derived C9ORF72 mutant motor neurons is associated with increased intracellular calcium release
S.B. was supported by a Motor Neuron Disease Association studentship (WadeMartins/Oct13/867-792) and D.A.B was supported by the Monument Trust Discovery Award (J-1403) from Parkinson’s UK. The work was supported by the Medical Research Council Dementias Platform UK Stem Cell Network (Grant MR/M024962/1 to RW-M).A large hexanucleotide repeat expansion in the C9ORF72 gene is the most prevalent cause of amyotrophic lateral sclerosis (ALS). To better understand neuronal dysfunction during ALS progression, we studied motor neuron (MN) cultures derived from iPSC lines generated from C9ORF72 (C9) expansion carriers and unaffected controls. C9 and control MN cultures showed comparable mRNA levels for MN markers SMI-32, HB9 and ISL1 and similar MN yields (> 50% TUJ1/SMI-32 double-positive MNs). Using whole-cell patch clamp we showed that C9-MNs have normal membrane capacitance, resistance and resting potential. However, immature (day 40) C9-MNs exhibited a hyperexcitable phenotype concurrent with increased release of calcium (Ca2+) from internal stores, but with no changes to NaV and KV currents. Interestingly, this was a transient phenotype. By day 47, maturing C9-MNs demonstrated normal electrophysiological activity, displaying only subtle alterations on mitochondrial Ca2+ release. Together, these findings suggest the potential importance of a developmental component to C9ORF72-related ALS.Publisher PDFPeer reviewe
Autologous transplantation of rabbit limbal epithelia cultured on fibrin gels for ocular surface reconstruction
Purpose: Regeneration of the corneal epithelium could be severely impaired in patients suffering from limbal stem cell
deficiency. The purpose of this study was to evaluate the restoration of the corneal epithelium by grafting onto denuded
corneas autologous limbal cells cultured on fibrin gels. The rabbit model was chosen to allow the microscopic evaluation
over time after grafting.
Methods: Rabbit limbal epithelial cells (RLECs) were isolated and cultured from small limbal biopsies (3 mm2
). The
epithelium was separated from stroma after dispase digestion and put in culture on lethally irradiated fibroblasts used as a
feeder layer. At the first passage, RLECs were cultured on a fibrin gel matrix. At confluence, the cultured epithelia were
grafted in vivo on denuded autologous rabbit corneas. At different postoperative times, grafted and control (without graft
or grafted with fibrin gels only) rabbit corneas were compared in vivo with a slit lamp microscope, and in situ by histological
and immunohistological microscopy of harvested biopsies.
Results: A small limbal biopsy was sufficient to generate enough RLECs to prepare several grafts and to perform cell
analysis. Only two weeks were required to produce a cultured epithelium suitable for autologous transplantation. One
month after grafting, a normal corneal phenotype was observed on the ocular surface of grafted rabbits in contrast to the
control rabbits (ungrafted or grafted with fibrin gel only) where histological signs of conjunctivalization were found. The
absence of goblet cells and negative staining for keratin 4 confirmed that the cultured cells persisted and that the epithelium
regenerated after grafting was not from conjunctival origin.
Conclusions: Our results demonstrate that an autologous epithelium cultured on a physiologically biodegradable matrix
can be prepared from a small biopsy and grafted on denuded cornea. The autologous graft allows epithelial regeneration
from cultured cells and promotes corneal healing of unilateral total stem cell deficiency
Evidence that pairing with genetically similar mates is maladaptive in a monogamous bird
<p>Abstract</p> <p>Background</p> <p>Evidence of multiple genetic criteria of mate choice is accumulating in numerous taxa. In many species, females have been shown to pair with genetically dissimilar mates or with extra-pair partners that are more genetically compatible than their social mates, thereby increasing their offsprings' heterozygosity which often correlates with offspring fitness. While most studies have focused on genetically promiscuous species, few studies have addressed genetically monogamous species, in which mate choice tends to be mutual.</p> <p>Results</p> <p>Here, we used microsatellite markers to assess individual global heterozygosity and genetic similarity of pairs in a socially and genetically monogamous seabird, the black-legged kittiwake <it>Rissa tridactyla</it>. We found that pairs were more genetically dissimilar than expected by chance. We also identified fitness costs of breeding with genetically similar partners: (i) genetic similarity of pairs was negatively correlated with the number of chicks hatched, and (ii) offspring heterozygosity was positively correlated with growth rate and survival.</p> <p>Conclusion</p> <p>These findings provide evidence that breeders in a genetically monogamous species may avoid the fitness costs of reproducing with a genetically similar mate. In such species that lack the opportunity to obtain extra-pair fertilizations, mate choice may therefore be under high selective pressure.</p
Primary physical education, coaches and continuing professional development
This is an Author's Accepted Manuscript of an article published in Sport, Education and Society, 16(4), 485 - 505, 2011, copyright @ Taylor & Francis, available online at: http://www.tandfonline.com/10.1080/13573322.2011.589645.Physical education (PE) in primary schools has traditionally been taught by qualified primary teachers. More recently, some teaching of PE in primary schools has been undertaken by coaches (mostly football coaches). These coaches hold national governing body awards but do not hold teaching qualifications. Thus, coaches may not be adequately prepared to teach PE in curriculum time. The purpose of this study was to evaluate the perceptions of a group of community-based football coaches working in primary schools for the impact of a Continuing Professional Development (CPD) programme on their ability to undertake ‘specified work’ to cover PE in primary schools. The programme focused on four areas identified as important to enable coaches to cover specified work: short- and medium-term planning, pedagogy, knowledge of the curriculum and reflection. Results showed that for the majority of coaches the CPD programme had made them more aware of the importance of these four areas and had helped to develop their knowledge and ability to put this into practice in covering planning, preparation and assessment time. However, further input is still required to develop coaches’ knowledge and understanding in all four areas, but especially their curriculum knowledge, as well as their ability to put these into practice consistently. These findings are discussed in relation to the implications of employing coaches to cover the teaching of PE in primary schools and, if employed, what CPD coaches need to develop the necessary knowledge, skill and understanding for covering specified work in schools
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Delivering word retrieval therapies for people with aphasia in a virtual communication environment
Background: Delivering therapy remotely, via digital technology, can enhance provision for people with aphasia. EVA Park is a multi-user virtual island that can be used for such delivery. The first EVA Park study showed that daily language stimulation delivered via the platform improved functional communication and was positively received by users (Marshall et al, 2016; Amaya et al, 2018). This paper reports two single case studies, evaluating its capacity to deliver targeted language interventions. The first employed therapy for noun retrieval, using cued picture naming and modified Sematic Feature Analysis. The second employed modified Verb Network Strengthening Treatment (VNeST).
Aims: This study aimed to determine if treatment delivery was feasible in EVA Park, as assessed by participant compliance, treatment fidelity and participants’ views. It explored the impact of the therapies on treated and untreated word production, connected speech and functional communication.
Methods & Procedures: Two participants with aphasia each received 20 sessions of individual therapy in EVA Park, delivered over 5 weeks. Feasibility was assessed by measuring compliance with the therapy regime, recording and checking the fidelity of 20% of treatment sessions, and using post therapy interviews to explore participant views. Treatment outcomes were evaluated via repeated measures single case designs, in which assessments were administered twice before therapy, immediately post therapy and five weeks later. Outcome measures included Object Picture Naming (study 1), Sentence Elicitation Pictures (study 2), Naming 84 items from the Object and Action Naming Battery (study 2), Narrative Production (Study 2), the Northwestern Assessment of Verb and Sentences: Argument Structure Production Test (Study 2) and Communication Activities of Daily Living – 2 (Study 1 & 2).
Outcomes & Results: Feasibility results were excellent. Both participants were fully compliant with the therapy regime. There was at least 90% fidelity with the treatment protocols and participant views were positive. Outcomes varied across the studies. The noun therapy significantly improved the naming of treated words, with good maintenance. Lexical gains were less evident on the Sentence Elicitation Pictures used in the VNeST study. Neither study demonstrated generalisation to untreated words, connected speech or functional communication.
Conclusions: Two treatment approaches, designed for face to face delivery, could be delivered remotely in EVA Park. Outcomes for the noun treatment were comparable to previous evaluations. Comparisons with previous research were more challenging for VNeST, owing to differences in methodology. Further evaluations of other treatment approaches are warranted
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Transforming CyberSecurity R&D within the Department of Energy: Getting Ahead of The Threat
This report outlines a preliminary response from DOE researchers to the following three questions: a) what are the key priorities w.r.t. cybersecurity R&D over the next decade? b) what would we recommend, in terms of a program, to address those priorities c) how would a DOE Office of Science program in this area complement other cybersecurity R&D initiatives such as NSF's or other agency programs
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Enhanced viability of corneal epithelial cells for efficient transport/storage using a structurally-modified calcium alginate hydrogel
Aims: Therapeutic limbal epithelial stem cells could be managed more efficiently if clinically validated
batches were transported for ‘on-demand’ use. Materials & methods: In this study, corneal epithelial cell
viability in calcium alginate hydrogels was examined under cell culture, ambient and chilled conditions
for up to 7 days. Results: Cell viability improved as gel internal pore size increased, and was further
enhanced with modification of the gel from a mass to a thin disc. Ambient storage conditions were optimal
for supporting cell viability in gel discs. Cell viability in gel discs was significantly enhanced with increases
in pore size mediated by hydroxyethyl cellulose. Conclusion: Our novel methodology of controlling alginate
gel shape and pore size together provides a more practical and economical alternative to established
corneal tissue/cell storage methods
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