209 research outputs found
Phosphorylation site sequence of smooth muscle myosin light chain (Mr = 20 000)
AbstractThe amino terminal sequence of the myosin light chain (Mr = 20 000) isolated from chicken gizzards was found to be acetyl-Ser-Ser-Lys-Arg-Ala-Lys-Ala-Lys-Thr-Thr-Lys-Lys-Arg-Pro-Gln-Arg-Ala-Thr-Ser(P)-Asn-Val-Phe. This sequence assignment differs from that reported by Maita et al. [(1981) European J. Biochem. 117, 417] in the order of the tryptic peptides. The revised amino acid sequence exhibits greater homology with the phosphorylation site sequences of the regulatory light chains from cardiac and skeletal muscle. Moreover it is now apparent why synthetic peptides corresponding to the previously reported sequence were very poor substrates for the myosin light chain kinase
Hydraulic fracturing: a review of theory and field experience
This report summarises the current state-of-the-art knowledge of the hydraulic fracturing process used by
the shale gas/oil industry using open peer-reviewed literature and from government commissioned
research reports. This report has been written to make statements on our knowledge of the following
questions:
• How do hydrofractures form?
• How far do hydrofractures extend during stimulation?
• What dictates where hydrofractures propagate?
• How do hydrofractures interact with the existing fracture network?
• Can the size and distribution of hydrofractures be controlled?
Gaps in our knowledge have been highlighted, with the largest of these resulting from differences between
North American and European shale rocks
The effects of anthropogenic pollution on the Kanev Reservoir (Ukraine) phytoplankton. 1. Phytoplankton dynamics at stations with different levels of pollution
The aim of the investigation was to compare the phytoplankton structure in two zones of the river part of Kanev Reservoir characterized by different levels of urban pollution. Two stations were selected for this purpose: 1, in a relatively pure area of the the river part of Kanev Reservoir; and 2, at the mouth of the Dneiper tributary, the Syrets River, which has been polluted by mineral and organic substances from urban sewage. The “vibrancy” of the phytoplankton was evaluated by determining their biomass, cell abundance, and cell surface area (denoted as B, N, and S, respectively), achieved on the basis of a routine monitoring dataset collected over 24 months at these stations. The investigated zones were characterized by divergent phytoplankton composition and considerably different annual dynamics. The profiles shown by the B, N and S dynamics of the phytoplankton at station 1 were characterized by regular and predictable peaks in summer, formed by the same complex of algal species. Similar-type graphs for station 2 exhibited 3-4 peaks per year formed by completely different groups of algae during different periods. Furthermore, the saprobic zone indicator species, as well as those characterized by highly specific cell-surface estimates, were often observed at station 2. Such species were absent or developed only to a minor extent in phytoplankton of station 1. These facts can be interpreted as symptoms of ecosystem destabilization at station 2, which could be due to the impact of polluted water from the Syrets River on the phytoplankton of the Kanev Reservoir.Исследованы структуры фитопланктона двух точек речной части Каневского водохранилища с разным уровнем загрязнения: ст. 1 – в сравнительно чистом районе его русловой части, ст. 2 – в устье притока Днепра, р. Сырец, загрязненной минеральными и органическими веществами с городских стоков. Динамика фитопланктона была оценена посредством определения его биомассы, численности и площади клеточной поверхности (B, N и S соответственно) на основе мониторинга данных, собранных на протяжении 24 мес. с обеих станций. Исследованные точки характеризовались разным видовым составом фитопланктона и существенно различной годовой динамикой. Кривые динамики B, N и S фитопланктона на ст. 1 характеризовались регулярными и предсказуемыми пиками в летний период, сформированными одинаковым комплексом видов водорослей. Такой же тип графиков для ст. 2 демонстрировал 3-4 пика в год, сформированных совершенно разными группами водорослей в течение разных периодов. Кроме того, водоросли-индикаторы высоких зон сапробности, а также характеризующиеся высокой удельной площадью поверхности клеток, часто наблюдались на ст. 2. Эти виды отсутствовали или развивались только в небольших количествах в фитопланктоне ст. 1, что свидетельствует о дестабилизации экосистемы на ст. 2 из-за влияния загрязненной воды из р. Сырец на фитопланктон Каневского водохранилища.Досліджено структури фітопланктону двох пунктів річкової частини Канівського водосховища з різним рівнем забруднення: ст. 1 – в порівняно чистому районі Дніпра, ст. 2 – в гирлі притоку Дніпра, р. Сирець, забрудненої мінеральними і органічними речовинами з міських стоків. Динаміка фітопланктону була оцінена шляхом визначення його біомаси, чисельності і площі клітинної поверхні (B, N і S відповідно) на основі моніторингу даних, зібраних протягом 24 місяців на обох станціях. Досліджувані пункти характеризувалися різним видовим складом фітопланктону і суттєво різною річною динамікою. Криві динаміки B, N і S фітопланктону на ст. 1 характеризувалися регулярними і передбачуваними піками в літній період, зформованими однаковим комплексом видів водоростей. Такий же тип графіків для ст. 2 демонстрував 3-4 піки на рік, зформовані зовсім різними групами водоростей протягом різних періодів. Крім того, водорості-індикатори високих зон сапробності, а також ті, що характеризуються високою питомою площиною поверхні клітин, часто спостерігалися на ст. 2. Ці види були відсутні або розвивалися в невеликій кількості у фітопланктоні ст. 1, що свідчить про дестабілізацію екосистеми на ст. 2 в результаті впливу забрудненої води з р. Сирець на фітопланктон Канівського водосховища
The position of graptolites within Lower Palaeozoic planktic ecosystems.
An integrated approach has been used to assess the palaeoecology of graptolites both as a discrete group and also as a part of the biota present within Ordovician and Silurian planktic realms. Study of the functional morphology of graptolites and comparisons with recent ecological analogues demonstrates that graptolites most probably filled a variety of niches as primary consumers, with modes of life related to the colony morphotype. Graptolite coloniality was extremely ordered, lacking any close morphological analogues in Recent faunas. To obtain maximum functional efficiency, graptolites would have needed varying degrees of coordinated automobility. A change in lifestyle related to ontogenetic changes was prevalent within many graptolite groups. Differing lifestyle was reflected by differing reproductive strategies, with synrhabdosomes most likely being a method for rapid asexual reproduction. Direct evidence in the form of graptolithophage 'coprolitic' bodies, as well as indirect evidence in the form of probable defensive adaptations, indicate that graptolites comprised a food item for a variety of predators. Graptolites were also hosts to a variety of parasitic organisms and provided an important nutrient source for scavenging organisms
Migration of the Antarctic Polar Front through the mid-Pleistocene transition: evidence and climatic implications
The Antarctic Polar Front is an important biogeochemical divider in the Southern Ocean. Laminated diatom mat deposits record episodes of massive flux of the diatom Thalassiothrix antarctica beneath the Antarctic Polar Front and provide a marker for tracking the migration of the Front through time. Ocean Drilling Program Sites 1091, 1093 and 1094 are the only deep piston cored record hitherto sampled from the sediments of the circumpolar biogenic opal belt. Mapping of diatom mat deposits between these sites indicates a glacial-interglacial front migration of up to 6 degrees of latitude in the early / mid Pleistocene. The mid Pleistocene transition marks a stepwise minimum 7 degree northward migration of the locus of the Polar Front sustained for about 450 kyr until an abrupt southward return to a locus similar to its modern position and further south than any mid-Pleistocene locus. This interval from a “900 ka event” that saw major cooling of the oceans and a ?13C minimum through to the 424 ka Mid-Brunhes Event at Termination V is also seemingly characterised by 1) sustained decreased carbonate in the subtropical south Atlantic, 2) reduced strength of Antarctic deep meridional circulation, 3) lower interglacial temperatures and lower interglacial atmospheric CO2 levels (by some 30 per mil) than those of the last 400 kyr, evidencing less complete deglaciation. This evidence is consistent with a prolonged period lasting 450 kyr of only partial ventilation of the deep ocean during interglacials and suggests that the mechanisms highlighted by recent hypotheses linking mid-latitude atmospheric conditions to the extent of deep ocean ventilation and carbon sequestration over glacial-interglacial cycles are likely in operation during the longer time scale characteristic of the Mid-Pleistocene Transition. The cooling that initiated the “900 ka event” may have been driven by minima in insolation amplitude related to eccentricity modulation of precession that also affected low latitude climates as marked by threshold changes in the African monsoon system. The major thresholds in earth system behaviour through the Mid-Pleistocene Transition were likely governed by an interplay of the 100 kyr and 400 kyr eccentricity modulation of precession
Epidemiology and health related quality of life in hypoparathyroidism in Norway.
OBJECTIVE: The epidemiology of hypoparathyroidism (HP) is largely unknown. We aimed to determine prevalence, etiologies, health related quality of life (HRQoL) and treatment pattern of HP. METHODS: Patients with HP and 22q11 deletion syndrome (DiGeorge syndrome) were identified in electronic hospital registries. All identified patients were invited to participate in a survey. Among patients who responded, HRQoL was determined by Short Form 36 (SF-36) and Hospital Anxiety and Depression scale (HADS). Autoantibodies were measured and candidate genes (CaSR, AIRE, GATA3 and 22q11-deletion) were sequenced for classification of etiology. RESULTS: We identified 522 patients (511 alive) and estimated overall prevalence at 102 per million divided among post-surgical HP (64 per million), non-surgical HP (30 per million) and pseudo-HP (8 per million). Non-surgical HP comprised autosomal dominant hypocalcemia (21%), autoimmune polyendocrine syndrome type 1 (17%), DiGeorge/22q11 deletion syndrome (15%), idiopathic HP (44%), and others, 4%. Among the 283 respondents (median age 53 years (range 9-89), 75% females), seven formerly classified as idiopathic were reclassified after genetic and immunological analyses, whereas 26 (17% of non-surgical HP) remained idiopathic. Most were treated with vitamin D (94%) and calcium (70%), and 10 received parathyroid hormone. HP patients scored significantly worse than the normative population on SF-36 and HADS; patients with post-surgical scored worse than those with non-surgical HP and pseudo-HP, especially on physical health. CONCLUSIONS: We found higher prevalence of non-surgical HP in Norway than reported elsewhere. Genetic testing and autoimmunity screening of idiopathic HP identified a specific cause in 21%. Further research is necessary to unravel the causes of idiopathic HP and to improve the reduced HRQoL reported by HP patients
Self-control and early adolescent antisocial behavior: A longitudinal analysis
Contains fulltext :
73179.pdf (publisher's version ) (Closed access)The article discusses a three-wave longitudinal study that investigates the relationship between self-control and aggressive and delinquent behavior of early adolescent boys and girls. The sample consists of 1,012 Dutch adolescents (mean age = 12.3) in their first year of secondary education. Structural equation modeling analyses reveal that high levels of self-control consistently decrease aggressive and delinquent behavior in the subsequent 6 months follow-up intervals. Results for the total sample do not support the hypothesis that self-control is influenced by previous levels of aggression or delinquency. For boys, the partial evidence found indicates reciprocal effects of self-control and delinquency.21 p
Determination of optimal glucose concentration for microcalorimetric metabolic evaluation of equine spermatozoa
Effect of age, sex and gender on pain sensitivity: A narrative review
© 2017 Eltumi And Tashani. Introduction: An increasing body of literature on sex and gender differences in pain sensitivity has been accumulated in recent years. There is also evidence from epidemiological research that painful conditions are more prevalent in older people. The aim of this narrative review is to critically appraise the relevant literature investigating the presence of age and sex differences in clinical and experimental pain conditions. Methods: A scoping search of the literature identifying relevant peer reviewed articles was conducted on May 2016. Information and evidence from the key articles were narratively described and data was quantitatively synthesised to identify gaps of knowledge in the research literature concerning age and sex differences in pain responses. Results: This critical appraisal of the literature suggests that the results of the experimental and clinical studies regarding age and sex differences in pain contain some contradictions as far as age differences in pain are concerned. While data from the clinical studies are more consistent and seem to point towards the fact that chronic pain prevalence increases in the elderly findings from the experimental studies on the other hand were inconsistent, with pain threshold increasing with age in some studies and decreasing with age in others. Conclusion: There is a need for further research using the latest advanced quantitative sensory testing protocols to measure the function of small nerve fibres that are involved in nociception and pain sensitivity across the human life span. Implications: Findings from these studies should feed into and inform evidence emerging from other types of studies (e.g. brain imaging technique and psychometrics) suggesting that pain in the older humans may have unique characteristics that affect how old patients respond to intervention
Volume I. Introduction to DUNE
The preponderance of matter over antimatter in the early universe, the dynamics of the supernovae that produced the heavy elements necessary for life, and whether protons eventually decay—these mysteries at the forefront of particle physics and astrophysics are key to understanding the early evolution of our universe, its current state, and its eventual fate. The Deep Underground Neutrino Experiment (DUNE) is an international world-class experiment dedicated to addressing these questions as it searches for leptonic charge-parity symmetry violation, stands ready to capture supernova neutrino bursts, and seeks to observe nucleon decay as a signature of a grand unified theory underlying the standard model. The DUNE far detector technical design report (TDR) describes the DUNE physics program and the technical designs of the single- and dual-phase DUNE liquid argon TPC far detector modules. This TDR is intended to justify the technical choices for the far detector that flow down from the high-level physics goals through requirements at all levels of the Project. Volume I contains an executive summary that introduces the DUNE science program, the far detector and the strategy for its modular designs, and the organization and management of the Project. The remainder of Volume I provides more detail on the science program that drives the choice of detector technologies and on the technologies themselves. It also introduces the designs for the DUNE near detector and the DUNE computing model, for which DUNE is planning design reports. Volume II of this TDR describes DUNE\u27s physics program in detail. Volume III describes the technical coordination required for the far detector design, construction, installation, and integration, and its organizational structure. Volume IV describes the single-phase far detector technology. A planned Volume V will describe the dual-phase technology
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