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To understand snow structure and snowmelt timing, information about flows of liquid water within the snowpack is essential. Models can make predictions using explicit representations of physical processes, or through parameterization, but it is difficult to verify simulations. In situ observations generally measure bulk quantities. Where internal snowpack measurements are made, they tend to be destructive and unsuitable for continuous monitoring. Here, we present a novel method for in situ monitoring of water flow in seasonal snow using the electrical self-potential (SP) geophysical method. A prototype geophysical array was installed at Col de Porte (France) in October 2018. Snow hydrological and meteorological observations were also collected. Results for two periods of hydrological interest during winter 2018–19 (a marked period of diurnal melting and refreezing, and a rain-on-snow event) show that the electrical SP method is sensitive to internal water flow. Water flow was detected by SP signals before it was measured in conventional snowmelt lysimeters at the base of the snowpack. This initial feasibility study shows the utility of the SP method as a non-destructive snow sensor. Future development should include combining SP measurements with a high-resolution snow physics model to improve prediction of melt timing.
Human donor milk (DM) is Holder pasteurised (62·5°C, 30 min) to ensure its microbiological safety for infant consumption. In low-resource settings, flash heating is used to pasteurise milk. Although there is considerable interest in non-thermal alternatives (high hydrostatic pressure processing (HHP) and UVC irradiation) for pasteurisation, their effect on the fatty acid composition is not well understood. Of particular interest is the effect of pasteurisation on the generation of oxylipins. DM from eight mothers containing bacteria >5 × 107 colony-forming units/l was used. In a paired design, each pool of milk underwent four pasteurisation techniques: Holder; flash heating; UVC (250 nm, 25 min) and HHP (500 MPa, 8 min). Fatty acids were quantified by GC-flame ionisation detection and oxylipins derived from arachidonic acid; 18-carbon PUFA (α-linolenic acid, linoleic acid and γ-linolenic acid) and EPA/DHA were measured by liquid chromatography-tandem MS in aliquots of raw and processed milk. There were no significant changes to the composition of fatty acids following all pasteurisation techniques compared with raw milk. The n-6:n-3 ratio remained constant ranging from 6·4 to 6·6. Several arachidonic acid-derived oxylipins were highest post-UVC and elevated post-HHP compared with raw milk. Several oxylipins derived from 18-carbon PUFA (linoleic and α-linolenic acids) were elevated in UVC-treated milk. EPA/DHA-derived oxylipins were on average, unaffected by pasteurisation. Although some PUFA-derived oxylipins were increased following UVC and HHP, no method affected the fatty acid composition of human DM. Further research is needed to determine if varying levels of oxylipins in human DM as a result of processing can potentially mediate cellular signalling; proliferation and apoptosis, especially important for preterm infant development.
A wide variety of surgical strategies are used in tetralogy of Fallot repair. We sought to describe the international contemporary practice patterns for surgical management of tetralogy of Fallot.
Surgeons from 18 international paediatric cardiac surgery centres (representing over 1800 tetralogy of Fallot cases/year) completed a Research Electronic Data Capture-based survey. Participating countries include: China (4), India (2), Nepal (1), Korea (1), Indonesia (1), Saudi Arabia (3), Japan (1), Turkey (1), Australia (1), United States of America (2), and Canada (1). Summary measures were reported as means and counts (percentages). Responses were weighted based on case volume/centre.
Primary repair is the prevalent strategy (83%) with variation in age at elective repair (range). Approximately 47% of sites use patient age as a factor in determining the strategy, with age <3 months being the common cut-off for staged repair. In addition, patient weight of <3 kg is an indication for staged repair in 80% of participating institutions. Trans-atrial ventricular septal defect closure is the preferred approach in 62% of sites. Approximately 70% of responders reported using pulmonary valve z-score to guide right ventricular outflow tract management technique with the most prevalent cut-off for annulus preservation being a z-score of −3. Estimated incidence of annulus preservation is 53%. Minimal trans-annular incision is performed in >90% of all trans-annular repairs.
In this cohort representing 11 countries, there is variation in tetralogy of Fallot surgical management with no consensus on standard of practice. A large international prospective cohort study would allow analysis of impact of underlying anatomy and repair strategy on early and late outcomes.
Genebanks are important suppliers of genetic resources to the genomics research community, and access to the resulting information will allow traditional genebank users to better select genetic material for their breeding and scientific programmes. We discuss herein a possible solution to interconnect these data automatically based on semantic web technology.
We present an exploration of the integrated stellar populations of early-type galaxies (ETGs) from the ATLAS3D survey. We use two approaches: firstly the application of line-indices interpreted through single stellar population (SSP) models, which provide a single value of age, metallicity and abundance ratio. And secondly, by fitting a linear combination of SSP spectra to our data, smoothly weighted in the free parameters of age and metallicity, thereby inferring a star-formation history of these galaxies. Despite the significant differences in these approaches, we obtain generally consistent results, such that galaxies that are more massive appear older with enhanced abundance ratios using line indices, and have shorter star-formation histories weighted to early times. We highlight two limitations of the index-SSP approach. Firstly the SSP-equivalent ages belie the fact that ETGs are overwhelmingly composed of ancient stars. Secondly, the young stellar contributions implied in our star formation histories are required to obtain realistic UV-optical colours. We remark that, even fitting solar-abundance models, we can recover a star-formation duration that correlates with the measured alpha-enhancement, in agreement with other recent work.
The bigeye cigarfish (Cubiceps pauciradiatus) is a small pelagic nomeid of the tropical world ocean, often recovered in the stomach contents of top predators such as
tunas, billfishes and marine mammals. In the Indian Ocean, a few studies
have investigated the biology and the ecology of this species that is one of
the most abundant fish of the intermediate trophic levels. In this paper, we
investigated the spatial distribution of C. pauciradiatus in the Indian Ocean using pelagic trawl catches carried out between 20°N and 45°S, and the importance
of bigeye cigarfish in the diet of 9 piscivorous fishes sampled by different
fishing gears in the western part of the Indian Ocean. The highest densities
were observed along the eastern coast of Africa and in the Arabian Sea (87
000 individuals per square nautical mile) during the South-West Monsoon and
in the eastern part of the Seychelles archipelago (62 200 ind. square nmi)
during the North-East Monsoon. Small sized bigeye cigarfish (20–80 mm SL)
was a regular and abundant prey (20 to 200 ind. per stomach) for schooling
predators exploited by purse seine fishery such as large yellowfin and
bigeye tunas chasing prey near the sea surface. Large sized bigeye cigarfish
(61–150 mm SL) occurred in small numbers (3 to 20 ind. per stomach) in the
stomach contents of swordfish and of large yellowfin and bigeye tunas caught
by longline sets at great depths. Large concentrations of bigeye cigarfish
occurred in zones of high productivity, and that species constituted
seasonally a strong link in the transfer of energy from low to high trophic
levels in this part of the Indian Ocean.
The effects of an n-3 PUFA-enriched diet on cardiac cell membrane phospholipid fraction compositions and associated protein kinase-C (PKC) translocation modification have never been studied in higher mammals. This is of importance since membrane fatty acid composition has been shown to influence PKC signalling pathways. In the present study, we have tested whether the incorporation of n-3 PUFA in cardiac membrane phospholipids correlated with changes in the fatty acid composition of diacylglycerols (DAG) and led to a differential translocation of PKC isoforms. Two groups of five dogs were fed the standard diet supplemented with palm oil or fish oil for 8 weeks. Dogs fed a fish oil-enriched diet showed a preferential incorporation of EPA and, to a lesser extent, of DHA, at the expense of arachidonic acid, in the circulating TAG, plasma phospholipids, erythrocyte phospholipids and cardiomyocyte phospholipid fractions. Analysis of 1,2-DAG fatty acid composition also indicated a preferential enrichment of EPA compared with DHA. Associated with these results, a reduction in the expression of PKC-δ and PKC-ε isoforms in the particulate fractions was observed whereas no effect was seen for PKC-α and PKC-ζ. We conclude that a fish oil-enriched diet induces a modification in fatty acid composition of cardiac membrane phospholipids, associated with a differential translocation of PKC isoforms. These results can be explained by the production of structurally different DAG that may participate in some of the protective effects of n-3 PUFA against various chronic diseases.
Describir las observaciones y percepciones de los médicos sobre los pacientes con esquizofrenia y obtener información sobre sus prácticas de prescripción de antipsicóticos.
Psiquiatras de Estados Unidos y de cinco países europeos (Francia, Alemania, Italia, España y Reino Unido), que prescribieron antipsicóticos a ≥ 15 pacientes con esquizofrenia en los 3 meses precedentes, proporcionaron datos sobre las características demográficas y clínicas de sus pacientes y sus prácticas de prescripción de antipsicóticos y características del fármaco que influyeron en la eleccción del mismo.
Se recogieron datos de 872 médicos sobre 6.523 pacientes (un 85% de europeos, un 15% de Estados Unidos). La mayoría de los pacientes tenía 25-44 años, el 63% eran hombres y el 66% se trataban de forma ambulatoria. Aproximadamente, el 50% de los pacientes sufrían disfunción moderada a grave; cerca del 50% estaban desempleados y el 34% y el 75% tomaban antipsicóticos convencionales o atípicos, respectivamente. Los síntomas positivos identificados con más frecuencia fueron ideas delirantes (73%), pensamiento desorganizado (59%) y alucinaciones (59%); los síntomas negativos más comunes fueron aislamiento social (54%), pobreza del pensamiento (39%) y afecto embotado (38%). Los motivos principales para la selección del antipsicóticofueron eficacia para los síntomas positivos (90%) o negativos (62%) y tolerabilidad (47%). Los síntomas negativos (71-77%) se controlaron inadecuadamente con más frecuencia que los positivos (47-60%). Algunos efectos adversos fueron sedación, aumento de peso y síntomas extrapiramidales.
En esta encuesta de gran tamaño, transversal multinacional, los médicos afirmaron que los síntomas positivos eran más comunes que los negativos. El tratamiento de los síntomas positivos fue más satisfactorio que el de los síntomas negativos, considerando los médicos que el tratamiento era inadecuado en más del 70% de los pacientes con síntomas negativos.
Concerns have been raised in Europe about the efficiency, sustainability,
and environmental impact of the first genetically modified crops. The
committees and regulators in charge of approving procedures have encouraged
a field trial approach for safety assessment studies under current agronomic
conditions. We describe the gene flow from sugar beet (Beta vulgaris L.) in a multi-year
and multi-crop monitoring study on farmers' fields at two locations that has
been carried out since 1995. We analyzed two sugar beet lines that have been
genetically transformed for herbicide resistance. One sugar beet has
resistance to glufosinate and the other to glyphosate. Large differences
among lines, years and locations were observed. These differences provided a
broad range of situations to estimate the risks. Sugar beet bolters produced
the majority (86%) of the herbicide-resistant seeds harvested in the
field. Direct pollen flow from sugar beet bolters to weed beets that were
growing within the same field as well as in a neighboring field that was
left fallow accounted for only 0.4% of the resistant seeds released over
the years and locations. Descendants of the hybrids between the sugar beet
and the weed beet produced the remaining 13.6% of resistant seeds.
Herbicide-resistant seeds from the progeny of the weed beet were recorded up
to 112 m away from the closest transgenic pollen donor. Indications were
observed of non-randomness of the weed beet producing resistant progeny. We
also analyzed pollen flow to male-sterile bait plants located within and
outside of the sugar beet field. Herbicide-resistant pollen flow was
recorded up to 277 m, and fitted with an inverse power regression. Using
sugar beet varieties with no, or very low, sensitivity to bolting and
destroying bolters are two necessary measures that could delay gene flow.
To describe physicians' observations and perceptions of patients with schizophrenia and to obtain information about antipsychotic prescribing practices.
Psychiatrists in the United States and five European countries (France, Germany, Italy, Spain, and the United Kingdom) who prescribed antipsychotics for ≥15 patients with schizophrenia within the preceding 3 months provided data on their patients' demographic and clinical characteristics and their antipsychotic prescribing practices and drug attributes influencing treatment choice.
Data were collected from 872 physicians on 6523 patients (85% European, 15% US). Most patients were aged 25–44 years, 63% were men, and 66% were outpatients. About 50% of patients were moderately to grossly dysfunctional; about 50% were unemployed; 34% and 75% were taking conventional or atypical antipsychotics, respectively. Frequently identified positive symptoms included delusions (73%), disordered thought (59%), and hallucinations (59%); common negative symptoms included social withdrawal (54%), impoverished thought (39%), and blunted affect (38%). Reasons for antipsychotic selection included efficacy for positive (90%) or negative symptoms (62%) and tolerability (47%). Inadequate control was reported more frequently for negative (71–77%) than positive (47–60%) symptoms. Adverse events included sedation, weight gain, and extrapyramidal symptoms.
In this large, multinational, cross-sectional survey, physicians reported that positive symptoms were more common than negative symptoms. Treatment for positive symptoms was more successful than that for negative symptoms, with physicians considering treatment inadequate for >70% of patients with negative symptoms.
The nature of the interface between Si and Ge substrates and high-k dielectrics often controls the performance of MOSFET devices. Precleaning and/or chemical functionalization of the surfaces can dramatically affect the formation of an interfacial layer. We have used in-situ IR spectroscopy to probe the relevant interfaces during ALD growth for a variety of surface treatments, including H- and Cl-termination, and nitridation. This paper focuses on understanding of the mechanisms for interfacial SiO2 (or GeOx) formation during HfO2 growth using tetrakis-ethylmethylamidohafnium (TEMAH) as the metal precursor and water or ozone as the oxygen precursor. We find that impurities arising from incomplete ligand elimination during growth (e.g. OH for H2O processing and CO- and NO-containing species for O3 processing) are incorporated into the HfO2 film during growth. Upon annealing, most of these species react, but can also migrate to the interface. Nitridation of Si and Ge surfaces will in general prevent SiO2 or GeOx formation but can also affect the growth rate.
Richard Samuels's book Machiavelli's Children: Leaders and Their Legacies in Italy and Japan raises a number of important issues concerning political leadership and the role individual leaders can play in a nation's history. The book won the 2003 Marraro Prize from the Society for Italian Historical Studies and the 2004 Jervis-Schroeder Prize for the best book in International History and Politics, awarded by the International History and Politics section of the American Political Science Association. This is a roundtable involving four critical essays and the author's response. Discussion centers on the book, its methods, its broader applicability, and the ways in which it dovetails with other intellectual concerns, particularly as these apply to contemporary East Asia.
Using a stochastic lattice model we have studied the architectural changes of trabecular bone occurring while the structure is remodeled. Our model considers the mechanical feedback loop, which control the remodeling process. A fast algorithm was employed to solve approximately the mechanical problem. A general feature of the model is that a networklike structure emerges, which further coarsens while the bone volume fraction remains unchanged. Decreasing the mechanical response of the system by either lowering the external load or the internal mechano-sensitivity leads not only to a reduction of the bone volume fraction, but results in topological changes of the trabecular bone architecture, where the loss of horizontal trabeculae is the most obvious effect.
Many snow models have been developed for various applications such as hydrology, global atmospheric circulation models and avalanche forecasting. The degree of complexity of these models is highly variable, ranging from simple index methods to multi-layer models that simulate snow-cover stratigraphy and texture. In the framework of the Snow Model Intercomparison Project (SnowMIP), 23 models were compared using observed meteorological parameters from two mountainous alpine sites. The analysis here focuses on validation of snow energy-budget simulations. Albedo and snow surface temperature observations allow identification of the more realistic simulations and quantification of errors for two components of the energy budget: the net short- and longwave radiation. In particular, the different albedo parameterizations are evaluated for different snowpack states (in winter and spring). Analysis of results during the melting period allows an investigation of the different ways of partitioning the energy fluxes and reveals the complex feedbacks which occur when simulating the snow energy budget. Particular attention is paid to the impact of model complexity on the energy-budget components. The model complexity has a major role for the net longwave radiation calculation, whereas the albedo parameterization is the most significant factor explaining the accuracy of the net shortwave radiation simulation.
We obtained narrow-band continuum images of the Crab Nebula at 16, 6.4 and 2.2 µm. From these we derive spectral index maps, extending the optical work of Véron-Cetty & Woltjer (1993). In the central parts of the Nebula the IR spectral index is close to the radio one, indicating the region where the radio-emitting electrons are accelerated.
To study the possible presence of staphylococcal enterotoxin A
goats' milk lactic cheese, milk was inoculated with an enterotoxigenic
aureus strain to a final concentration of 4, 5 and 6 log(cfu/ml).
Cheese was prepared
following industrial specifications and ripened for 42 d. Detection of
was by the Vidas Staph enterotoxin test (BioMérieux) and by an indirect
double-sandwich ELISA technique using anti-enterotoxin monoclonal antibodies.
counts declined markedly after draining, and by the end of ripening they
had disappeared from some cheeses. In contrast, aerobic mesophilic organisms
well. The level of staphylococcal enterotoxin A recovered varied from 1
to 2·5 ng/g
cheese made with an initial population of 105 or
106 cfu/ml. Only traces of
enterotoxin A (0·5 ng/g) were detected in cheeses made
with the lowest Staph. aureus
inoculum used in this study. Enterotoxin A was also detected in cheeses
Staph. aureus had disappeared.
Pleistocene deposits in alpine Pierre Saint-Martin cave are preserved in an abandoned river gallery. The deposits, 300 m long and 25 m high, are composed of a lower unit of fallen blocks overlain by debris flows, a main unit of laminated clay, and a series of river terraces inset into these units. The lower and main units are each overlain by speleothems. The lower unit represents a cold period, probably isotope stage 10. Corroded speleothems above it have given U/Th ages greater than 300,000–330,000 yr B.P. The main unit, with carbonate-rich varves devoid of pollen, represents a glaciation that occurred before 225,000 yr B.P. and probably correlates with stage 8, even though such a glaciation has not been previously recognized in the Pyrenees. The river terraces, covered by many noncorroded speleothems, probably formed during stage 7 (U/Th ages between 194,000 and 211,000–225,000 yr B.P.). Subsequent sinking of an underground river protected the deposits from erosion.