2,180 research outputs found
Review of the Monitoring Programme: Baseline Measurement and Analysis of UK Ozone and UV
The Department for Environment, Food and Rural Affairs (Defra) and the Devolved Administrations (DA) continue to fund a long-running programme Baseline Measurement and Analysis of UK Ozone and UV to monitor column (effectively stratospheric) ozone and surface UV. The main driver for the monitoring programme is the 1985 Vienna Convention on the Protection of the Ozone Layer. The Convention obliges parties (including the UK) to undertake inter alia monitoring, data dissemination and information exchange activities.
The current monitoring programme comprises:
• measurements of column ozone at two sites in the UK (Lerwick and Reading)
• spectrally-resolved UV measurements at one site (Reading)
The ozone element of the monitoring programme was reviewed in 2002. Defra has commissioned this review of the programme to ensure that it continues to meet current and future policy and scientific requirements as well as international obligations.
The Review
The review was structured in terms of 7 questions, which addressed a range of strategic, technical and organisational aspects of the monitoring programme.
1. How does the monitoring programme help to meet the UK obligations under the Vienna Convention on the Protection of the Ozone Layer?
2. Are the data currently collected in the monitoring programme fit for purpose?
If not, what measures could be employed to make the data fit for purpose? Are there any activities in the current monitoring programme which are no longer needed?
3. Are the current measurement techniques viable into the future (over a 5-20 year timescale), and what other techniques/instruments are available?
4. Are current methodologies for disseminating information sufficient?
If other techniques/instruments are preferable, how (or indeed could) they be introduced whilst maintaining the continuity of the results?
5. Is the current monitoring programme cost effective?
6. Is the current monitoring programme structured for optimum delivery?
7. Should all or part of the programme be competitively tendered, or indeed should it be competitively tendered at all?
Summary of Findings
The key findings were
1. The current monitoring programme is working well but it has a low profile and impact
2. There are options to evolve the programme but these require further, more detailed evaluation
The contribution of cool and hot executive function to academic achievement, learning-related behaviours, and classroom behaviour
The primary aim of this study was to examine whether individual differences in cool and hot executive functions (EF) were associated with children’s transition to school, in terms of both academic performance and classroom behaviour. Children between 5- and 7-years-of-age (N = 90) completed performance based assessments of cool and hot EF as well as verbal ability. Teachers reported on children’s reading and numeracy performance, learning-related behaviours, hyperactivity, and aggression. Results revealed that EF, in particular working memory, was associated with reading and numeracy performance and that this relation was mediated by learning-related behaviours. EF was not associated with hyperactive or aggressive behaviour. The findings strengthen the evidence base for the importance of EF in early academic performance and underscore its potential to be a beneficial part of early education curriculum and a target for early intervention for successful transition to school
Organellar Contacts of Milk Lipid Droplets
Milk-secreting epithelial cells of the mammary gland are functionally specialized for the synthesis and secretion of large quantities of neutral lipids, a major macronutrient in milk from most mammals. Milk lipid synthesis and secretion are hormonally regulated and secretion occurs by a unique apocrine mechanism. Neutral lipids are synthesized and packaged into perilipin-2 (PLIN2) coated cytoplasmic lipid droplets within specialized cisternal domains of rough endoplasmic reticulum (ER). Continued lipid synthesis by ER membrane enzymes and lipid droplet fusion contribute to the large size of these cytoplasmic lipid droplets (5–15 μm in diameter). Lipid droplets are directionally trafficked within the epithelial cell to the apical plasma membrane. Upon contact, a molecular docking complex assembles to tether the droplet to the plasma membrane and facilitate its membrane envelopment. This docking complex consists of the transmembrane protein, butyrophilin, the cytoplasmic housekeeping protein, xanthine dehydrogenase/oxidoreductase, the lipid droplet coat proteins, PLIN2, and cell death-inducing DFFA-like effector A. Interactions of mitochondria, Golgi, and secretory vesicles with docked lipid droplets have also been reported and may supply membrane phospholipids, energy, or scaffold cytoskeleton for apocrine secretion of the lipid droplet. Final secretion of lipid droplets into the milk occurs in response to oxytocin-stimulated contraction of myoepithelial cells that surround milk-secreting epithelial cells. The mechanistic details of lipid droplet release are unknown at this time. The final secreted milk fat globule consists of a triglyceride core coated with a phospholipid monolayer and various coat proteins, fully encased in a membrane bilayer
Organellar Contacts of Milk Lipid Droplets
Milk-secreting epithelial cells of the mammary gland are functionally specialized for the synthesis and secretion of large quantities of neutral lipids, a major macronutrient in milk from most mammals. Milk lipid synthesis and secretion are hormonally regulated and secretion occurs by a unique apocrine mechanism. Neutral lipids are synthesized and packaged into perilipin-2 (PLIN2) coated cytoplasmic lipid droplets within specialized cisternal domains of rough endoplasmic reticulum (ER). Continued lipid synthesis by ER membrane enzymes and lipid droplet fusion contribute to the large size of these cytoplasmic lipid droplets (5–15 μm in diameter). Lipid droplets are directionally trafficked within the epithelial cell to the apical plasma membrane. Upon contact, a molecular docking complex assembles to tether the droplet to the plasma membrane and facilitate its membrane envelopment. This docking complex consists of the transmembrane protein, butyrophilin, the cytoplasmic housekeeping protein, xanthine dehydrogenase/oxidoreductase, the lipid droplet coat proteins, PLIN2, and cell death-inducing DFFA-like effector A. Interactions of mitochondria, Golgi, and secretory vesicles with docked lipid droplets have also been reported and may supply membrane phospholipids, energy, or scaffold cytoskeleton for apocrine secretion of the lipid droplet. Final secretion of lipid droplets into the milk occurs in response to oxytocin-stimulated contraction of myoepithelial cells that surround milk-secreting epithelial cells. The mechanistic details of lipid droplet release are unknown at this time. The final secreted milk fat globule consists of a triglyceride core coated with a phospholipid monolayer and various coat proteins, fully encased in a membrane bilayer
The development and validation of a teacher-reported low-level classroom disruption scale (LLCD-S)
Low-level classroom disruption (LLCD) is characterised by pupils swinging on chairs, whispering or fidgeting in class. This paper provides initial data on the development and validation of the teacher-rated Low-Level Classroom Disruption Scale (LLCD-S), with two samples of primary school pupils. Exploratory factor analysis in Study 1 (N= 120) revealed one factor accounting for 61% of the variance; supported by confirmatory factor analysis in Study 2 (N= 274), with one factor accounting for 63% of the variance. Both studies reported high Cronbach’s alpha values of.82 and.93 respectively. The evidence supports LLCD being a unidimensional construct, measured by the eight item LLCD-S. Weak convergence validity was found between the LLCD-S and the Strengths and Difficulties Questionnaire’s (SDQ) externalising behaviours: conduct problems and hyperactivity. This preliminary evidence indicates that LLCD-S is a valid and reliable measure of low-level classroom disruption. Further research is needed to test the utility of the LLCD-S across different levels of education, cultures and as a pupil-reported measure
A Qualitative Exploration of Practitioners' Understanding of and Response to Child-to-Parent Aggression.
There has been limited research and policy directed toward defining and understanding child-to-parent aggression (CPA), resulting in inconsistent definitions, understandings, and responses, which has a detrimental impact on families. In particular, there have been limited qualitative studies of those working on the frontline of CPA, hindering the development of effective policy. The present qualitative study therefore aimed to explore practitioner perspectives of CPA. Twenty-five practitioners from diverse fields (e.g., youth justice, police, charities) participated in four focus groups relating to their experiences of working with CPA in the United Kingdom. Thematic analysis of focus groups revealed three key themes: definitions of CPA, understanding of CPA risk factors, and responding to CPA. Practitioners understood CPA to be a broad use of aggression to intimidate and control parents and highlighted a range of individual (e.g., mental health, substance abuse) and social (e.g., parenting, gangs) risk factors for CPA. Further, practitioners felt that current methods of reporting CPA were ineffective and may have a detrimental impact on families. The findings of this study have implications for CPA policy and support the need for a multiagency and coordinated strategy for responding to CPA
Evaluating conservation strategies for the endangered daisy Schoenia filifolia subsp. subulifolia (Asteraceae): fitness consequences of genetic rescue and hybridisation with a widespread subspecies
Context: To establish translocated populations of threatened plants with the genetic resources to adapt to changing environmental conditions, the source of propagation material is an important consideration.
Aim: We investigated the fitness consequences of genetic rescue and admixture for the threatened annual daisy Schoenia filifolia subsp. subulifolia, and the common S. filifolia subsp. filifolia, to inform seed-sourcing strategies for translocations of the threatened subspecies.
Methods: We evaluated genetic diversity of two populations of S. filifolia subsp. subulifolia and four populations of S. filifolia subsp. filifolia by using microsatellite markers. We grew seedlings from each study population and cross-pollinated inflorescences within and among populations of the same subspecies, and between subspecies. We evaluated the fitness consequences of each cross by using seed set, seed weight and seed viability.
Key results: There was a lower genetic diversity in the small (10 000 plants, Nar = 4.42, He = 0.51) population of S. filifolia subsp. subulifolia, although none of the measures was significantly different, and seed fitness was slightly, although not significantly, reduced in interpopulation crosses compared with the small population. Genetic diversity was similar between the threatened and widespread subspecies; however, the subspecies were genetically divergent (Fst = 0.242–0.294) and cross-pollination between subspecies produced negligible amounts of seeds (<3% seed set).
Conclusions: Although genetic rescue or admixture of S. filifolia subsp. subulifolia would not necessarily result in greatly increased levels of genetic diversity or seed fitness, we still consider it a potential option. Negligible seed set in crosses between subspecies indicates that deliberate hybridisation is not a possibility.
Implications: Studies of fitness consequences of admixture or genetic rescue are rare yet critical to assessing the benefits of different translocation strategies
The TOMCAT global chemical transport model v1.6: description of chemical mechanism and model evaluation
This paper documents the tropospheric chemical mechanism scheme used in the TOMCAT 3-D chemical transport model. The current scheme includes a more detailed representation of hydrocarbon chemistry than previously included in the model, with the inclusion of the emission and oxidation of ethene, propene, butane, toluene and monoterpenes. The model is evaluated against a range of surface, balloon, aircraft and satellite measurements. The model is generally able to capture the main spatial and seasonal features of high and low concentrations of carbon monoxide (CO), ozone (O3), volatile organic compounds (VOCs) and reactive nitrogen. However, model biases are found in some species, some of which are common to chemistry models and some that are specific to TOMCAT and warrant further investigation. The most notable of these biases are (1) a negative bias in Northern Hemisphere (NH) winter and spring CO and a positive bias in Southern Hemisphere (SH) CO throughout the year, (2) a positive bias in NH O3 in summer and a negative bias at high latitudes during SH winter and (3) a negative bias in NH winter C2 and C3 alkanes and alkenes. TOMCAT global mean tropospheric hydroxyl radical (OH) concentrations are higher than estimates inferred from observations of methyl chloroform but similar to, or lower than, multi-model mean concentrations reported in recent model intercomparison studies. TOMCAT shows peak OH concentrations in the tropical lower troposphere, unlike other models which show peak concentrations in the tropical upper troposphere. This is likely to affect the lifetime and transport of important trace gases and warrants further investigation
Peroxy radicals in the summer free troposphere: seasonality and potential for heterogeneous loss
The sum of peroxy radicals (HO2+ΣiRiO2) and supporting trace gases were measured on the Jungfraujoch (3580 m a.s.l.) during the late summer of 2005. The period was marked by extended times of heavy snow which led to reduction in the observed peroxy radicals during the snowy periods that was greater than the concomitant reduction in j(O1D). In the limit a first order loss rate of 0.0063 s−1 can be derived for the peroxy radical loss in the snowy conditions that could be potentially ascribed to a heterogenous loss process. On snow free days photolysis of HCHO is shown to be a significant peroxy radical source. The seasonal trends of the peroxy radical concentrations have been mapped from the winter to summer transition in line with previous experiments. Net ozone production in late summer at the Jungfraujoch was net neutral to marginally ozone destructive. A value of 28±4 pptv is calculated for the ozone compensation point for the snow free days.ISSN:1680-7375ISSN:1680-736
Tbx1 and Brn4 regulate retinoic acid metabolic genes during cochlear morphogenesis
<p>Abstract</p> <p>Background</p> <p>In vertebrates, the inner ear is comprised of the cochlea and vestibular system, which develop from the otic vesicle. This process is regulated via inductive interactions from surrounding tissues. <it>Tbx1</it>, the gene responsible for velo-cardio-facial syndrome/DiGeorge syndrome in humans, is required for ear development in mice. <it>Tbx1 </it>is expressed in the otic epithelium and adjacent periotic mesenchyme (POM), and both of these domains are required for inner ear formation. To study the function of <it>Tbx1 </it>in the POM, we have conditionally inactivated <it>Tbx1 </it>in the mesoderm while keeping expression in the otic vesicle intact.</p> <p>Results</p> <p>Conditional mutants (<it>TCre-KO</it>) displayed malformed inner ears, including a hypoplastic otic vesicle and a severely shortened cochlear duct, indicating that <it>Tbx1 </it>expression in the POM is necessary for proper inner ear formation. Expression of the mesenchyme marker <it>Brn4 </it>was also lost in the <it>TCre-KO</it>. <it>Brn4</it><sup>-</sup>;<it>Tbx1</it><sup>+/-</sup>embryos displayed defects in growth of the distal cochlea. To identify a potential signal from the POM to the otic epithelium, expression of retinoic acid (RA) catabolizing genes was examined in both mutants. <it>Cyp26a1 </it>expression was altered in the <it>TCre-KO</it>, while <it>Cyp26c1 </it>showed reduced expression in both <it>TCre-KO </it>and <it>Brn4</it><sup>-</sup>;<it>Tbx1</it><sup>+/- </sup>embryos.</p> <p>Conclusion</p> <p>These results indicate that <it>Tbx1 </it>expression in the POM regulates cochlear outgrowth potentially via control of local retinoic acid activity.</p
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