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This article discusses a study on the assessment of the value of treatment for moderate-to-severe atopic dermatitis (AD) using multi-criteria decision analysis (MCDA). The study aims to determine the most important health outcomes for decision-making from different perspectives. The results show that the value of a new AD treatment is primarily determined by its impact on improving patients' quality of life, controlling the disease, and reducing itching. However, there are differences in how AD patients and experts assess value, emphasizing the importance of considering the patient's opinion. The study acknowledges the limitations of the MCDA methodology and proposes a comprehensive set of criteria for evaluating AD treatments. The report was written by multiple authors and further exploration of the document is necessary to understand the specific topics and perspectives discussed. [Extracted from the article]

In the last two decades, nano-mechanical resonators have risen as highly promising devices for mass sensing due to their ultrahigh sensitivity. They can be used to measure the mass and stiffness of single particles like small pollution particles, viruses, bacteria, or even proteins. These capabilities of the nano-mechanical resonators have allowed the birth of a new type of mass spectrometry with no need of fragmentation or ionization of the sample and therefore ideal to measure big masses, where conventional mass spectrometers have important problems. The shape and modes of vibration of a nano-mechanical resonator can be very different and the advantages and drawbacks of one respect to another is still a hot topic. A unified theoretical framework to describe the effect of particle adsorption on a mechanical resonator is fundamental but still lacks in the literature. In this work, we present such a framework and examine the particular case of a rod-like particle adsorbed on a cantilever beam for flexural and torsional vibrations as well as on a disk resonator for radial breathing vibrations and compare the results with finite element simulations. [ABSTRACT FROM AUTHOR]

Background: Health-related quality of life (HRQoL) of patients with X-linked hypophosphatemia (XLH) is lower than that of both the general population and the patients with other chronic diseases, mainly due to diagnostic delay, treatment difficulties, poor psychosocial support, and problems with social integration. Early diagnosis and optimal treatment are paramount to control the disease in patients with XLH, avoid complications, and maintain or improve their HRQoL. We, therefore, analyzed the HRQoL of pediatric and adult patients with XLH treated with conventional therapy in Spain.Results: We used several versions of the EuroQol-5 dimensions (EQ-5D) instrument according to the age of patients with XLH. Then we compared the HRQoL of patients to that of the general Spanish population. Children with XLH (n = 21) had moderate problems in walking about (61.9%), washing or dressing themselves (9.52%), and performing their usual activities (33.33%). They also felt moderate pain or discomfort (61.9%) and were moderately anxious or depressed (23.81%). Adults with XLH (n = 29) had lower HRQoL, with problems in walking (93%, with 3.45% unable to walk independently), some level of pain (86%, with 3.45% experiencing extreme pain), problems with their usual activities (80%) and self-care (> 50%), and reported symptoms of anxiety and/or depression (65%). There were important differences with the general Spanish population.Conclusions: XLH impacts negatively on physical functioning and HRQoL of patients. In Spanish patients with XLH, the HRQoL was reduced despite conventional treatment, clearly indicating the need to improve the therapeutic approach to this disorder. [ABSTRACT FROM AUTHOR]

CAR-T cell therapy represents a therapeutic revolution in the prognosis and treatment of patients with certain types of hematological cancer. However, they also pose new challenges in the healthcare, regulatory and financial fields. The aim of the RET-A project was to undertake a strategic reflection on the management of CAR-T therapies within the Spanish National Health System, to agree on recommendations that will help to better deal with the new context introduced by these cell therapies in the present and in the future. This think tank involved 40 key agents and opinion leaders. The experts identified three great challenges for implementing advanced therapies in Spain: therapeutic individualisation, with a multidisciplinary approach; acceleration of access times, by minimizing bureaucracy; and increase in the number of centers qualified to manage the CAR-T therapies in the NHS. The experts agreed on the ideal criteria for designating those qualified centers. They also agreed on a comprehensive CAR-T care pathway with the timings and roles which would ideally be involved in each part of the process. [ABSTRACT FROM AUTHOR]

Objectives: To determine whether nutritional risk is associated with the mortality of elderly patients hospitalized with nonvalvular atrial fibrillation (NVAF). Design: Prospective, multicenter cohort study. Setting: Internal medicine departments in Spain. Participants: Inpatients >75 years with NVAF. Measurements: We measured the thrombotic and hemorrhagic risk at admission using the CHA2DS2-VASc and HAS-BLED scales, respectively, and the nutritional risk with the controlling nutritional status (CONUT) index. We established 4 degrees of nutritional risk: null (CONUT score 0–1 point), low (2–4 points), moderate (5–8 points) and high (9–12 points). We also conducted a 1-year follow-up. Results: We included 449 patients, with a mean age of 85.2(5.2) years. The nutritional risk was null for 70(15.6%) patients, low for 206 45.9%), moderate for 152(33.8%) and high for 21(4.7%). At the end of one year, 177(39.4%) patients had died. The score on the CONUT index was higher for the deceased patients (4.6 vs. 3.6, p<0.001). The CONUT score (HR, 1.076; 95%CI 1.009–1.148; p=0.025), the Charlson index (HR, 1.080; 95%CI 1.017–1.148; p=0.013) and the presence of pressure ulcers (HR, 1.700; 95%CI 1.028–2.810; p=0.039) were independently associated with increased mortality at one year of follow-up. The prescription of oral anticoagulants at discharge was associated with lower mortality (HR, 0.440; 95%CI 0.304–0.638; p<0.001). Conclusions: More than a third of elderly patients hospitalized with NVAF have a moderate to high nutritional risk. These patients have greater mortality at the end of one year. [ABSTRACT FROM AUTHOR]

We investigated the influence of seagrass canopies on the benthic biodiversity of bacteria and macroinvertebrates in a Red Sea tropical lagoon. Changes in abundance, number of taxa and assemblage structure were analyzed in response to seagrass densities (low, SLD; high, SHD; seagrasses with algae, SA), and compared with unvegetated sediments. Biological and environmental variables were examined in these four habitats (hereafter called treatments), both in the underlaying sediments and overlaying waters, at three randomly picked locations in March 2017. Differences between treatments were more apparent in the benthic habitat than in the overlaying waters. The presence of vegetation (more than its cover) and changes in sedimentary features (grain size and metals) at local scales influenced the observed biological patterns, particularly for macroinvertebrates. Of note, the highest percentage of exclusive macroinvertebrate taxa (18% of the gamma diversity) was observed in the SHD treatment peaking in the SA for bacteria. Benthic macroinvertebrates and bacteria shared a generally low number of taxa across treatments and locations; approximately, 25% of the gamma diversity was shared among all treatments and locations for macrofauna, dropping to 11% for bacteria. Given the low overlap in the species distribution across the lagoon, sustaining the connectivity among heterogeneous soft sediment habitats appears to be essential for maintaining regional biodiversity. This study addresses a current scientific gap related to the relative contributions of vegetated and unvegetated habitats to biodiversity in tropical regions. [ABSTRACT FROM AUTHOR]

We present an optical microscopy technique based on the scanning of a laser beam across the surface of a sample and the measurement of the deflection of the reflected laser beam in two dimensions. The technique is intended for characterization of nanomechanical systems. It provides the height of a nanomechanical system with sub-nanometer vertical resolution. In addition, it simultaneously provides a complete map of the resonant properties. We demonstrate the capability of the technique by analyzing the residual stress and vibration mode shape of a system consisting of two elastically coupled nanocantilevers. The technique is simple, allows imaging in air, vacuum and liquids, and it is unique in providing synchronized information of the static and dynamic out-of-plane displacement of nanomechanical systems. [ABSTRACT FROM AUTHOR]

In this study, we have determined the relationship between the nanostructure of the gold film deposited on microcantilevers and the sensitivity and reproducibility of their static response to molecular adsorption. In order to tune the properties of the gold film, gold was deposited at different rates and thicknesses. The cantilever response to molecular adsorption was characterized by exposure of the cantilevers to mercaptohexanol in water. The morphology of the gold surface was characterized by atomic force microscopy, and the residual stress induced in the cantilevers was characterized by a profilometry technique based on the optical beam deflection method. We have found that the discontinuous morphology of the gold film for small thicknesses and low deposition rates gives rise to large values of residual tensile stress due to the formation of grain boundaries at the expense of strain energy. These cantilevers exhibit the highest sensitivity and reproducibility to molecular adsorption. However, larger thicknesses and higher deposition rates produce the coalescence of gold nanoislands via atom diffusion. This is characterized by a large relative decrease (increase) of the tensile (compressive) stress. These cantilevers exhibit small sensitivity and low reproducibility to molecular adsorption. We conclude that the control of the gold coating process is critical for the reliability of the measurements with nanomechanical sensors. [ABSTRACT FROM AUTHOR]

We report the selective excitation of the flexural modes of microcantilevers in aqueous solutions, by applying the photothermal excitation technique. The experiments show that a particular vibration mode can be efficiently excited by focusing the intensity-modulated laser beam on regions of high curvature of the vibration shape. In addition, the resulting resonant peaks in liquid appear distorted by an amplitude component that decreases with the frequency. This distortion produces a shift of the resonance to lower frequencies. A theoretical model based on the transformation of optical energy into mechanical energy via an intermediate thermal stage is proposed to interpret the experimental results. The theory shows that the driven oscillation of the cantilever depends on the curvature of the eigenmode at the excitation position and the heating induced by the excitation laser, which decreases with the frequency. The results reported here set the basis for efficient excitation of high vibration modes in liquids and for optimized design of optically driven microresonators. [ABSTRACT FROM AUTHOR]

Using real-time in situ laser light scattering we study, in this work, the influence of growth kinetics on the initial development of the crosshatched morphology and its subsequent evolution. The crosshatched morphology is characteristic of relaxed low strained layers (ε< 2%) and has been traditionally related to the plastic relaxation process driven by generation and multiplication of dislocations. However we have observed that, if the growth rate is slow enough, the onset of crosshatch formation takes place at a layer thickness in which the dislocation formation and multiplication processes have not appeared yet. This reveals that the stress field generated by the small density of misfit dislocations formed by bending of the dislocations preexisting in the substrate is strong enough to affect the evolution of the growth front morphology. Our results also show that the starting point and evolution of this characteristic morphology depend on the growth rate in such a way that when the growth rate is lower the crosshatched morphology starts to develop at a smaller thickness and shows a faster evolution rate. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The Asian tiger mosquito, Aedes albopictus (Diptera: Culicidae), is a highly invasive species and a vector of several viruses of serious concern to public health. Investigating the habitat selection of this species at small to medium scales is essential to the planning of effective prevention and control campaigns. The present group considered detailed data for this species' presence/absence collected at 228 sites on Mallorca Island (Spain) in autumn 2015, 3 years after the first detection of the species on the island. Site occupancy models accounting for false negative detections and imperfect monitoring were used to evaluate the relationships between mosquito presence and habitat variables. In the study area, mosquito presence was negatively associated with altitude, probably as a result of greater human presence at low altitudes near the coast. Moreover, the presence of Ae. albopictus was positively associated with swimming pools as a result of associated gardens, plants and sources of fresh water. These two variables were combined to predict the presence of the species across the entire island. Three years after its arrival, the probability of the presence of the mosquito Aedes albopictus (Diptera: Culicidae) in Mallorca was 83% and was highest in coastal and tourist areas.On the island of Mallorca, mosquito presence was negatively associated with altitude, probably as a result of greater human presence at low altitudes near the coast.The presence of Ae. albopictus was positively associated with swimming pools as a result of associated gardens, plants and fresh water sources. [ABSTRACT FROM AUTHOR]

Ultrasensitive physical, chemical and biological sensors have emerged in the last decade based on the measurement of the eigenfrequencies of micro- and nanosized cantilever plates. Surface stress is omnipresent in these devices due to a variety of factors such as the fabrication process, temperature variations and analyte adsorption. How surface stress influences on the eigenfrequencies of cantilever plates has remained as an unsolved question in physics that has raised a long debate since first experiments in 1975. Recent theoretical models have shed light on the role of the net surface stress. Still, there exists a discrepancy between theory and some experimental reports, affecting to the capability for quantification of these sensors. In this Letter, we present a theoretical framework that demonstrates that the cantilever bending due to differential surface stress between opposite faces of the cantilever, a neglected effect in classical beam theory, plays a relevant role in the stiffness and eigenfrequencies of cantilevers. We develop a new theoretical framework that provides analytical equations that accurately describe the effect of surface stress on the first three vibration modes of cantilevers. Our findings provide the final piece of the puzzle for solving this long-standing problem in physics. [ABSTRACT FROM AUTHOR]

Precision medicine is an emerging approach for disease treatment and prevention that takes into account individual variability in genes, environment, and lifestyle for each person. Precision medicine is transforming clinical and biomedical research, as well as health care itself from a conceptual, as well as a methodological viewpoint, providing extraordinary opportunities to improve public health and lower the costs of the healthcare system. However, the implementation of precision medicine poses ethical-legal, regulatory, organizational, and knowledge-related challenges. Without a national strategy, precision medicine, which will be implemented one way or another, could take place without the appropriate planning that can guarantee technical quality, equal access of all citizens to the best practices, violating the rights of patients and professionals, and jeopardizing the solvency of the healthcare system. With this paper from the Spanish Societies of Medical Oncology, Pathology, and Hospital Pharmacy, we highlight the need to institute a consensual national strategy for the development of precision medicine in our country, review the national and international context, comment on the opportunities and challenges for implementing precision medicine, and outline the objectives of a national strategy on precision medicine in cancer. [ABSTRACT FROM AUTHOR]

Resonant microcantilevers are being actively investigated as sensitive mass sensors for biological detection. By performing experiments of adsorption of the bacteria Escherichia coli on singly clamped microcantilevers, we demonstrate that the effect of the added mass is not the only and may not be the main origin of the response of these sensors. The experiments show that the magnitude and sign of resonance frequency shift both depend critically on the distribution of the adsorbed bacterial cells on the cantilever. We relate this behavior to the added mass that shifts the resonance to lower frequencies and the higher effective flexural rigidity of the cantilever due to the bacteria stiffness that shifts the resonance to higher frequencies. Both effects can be uncoupled by positioning the cells where each effect dominates, near the free cantilever end for measuring the added mass or near the clamping for measuring the increase of flexural rigidity. [ABSTRACT FROM AUTHOR]

Blood contains a range of protein biomarkers that could be used in the early detection of disease. To achieve this, however, requires sensors capable of detecting (with high reproducibility) biomarkers at concentrations one million times lower than the concentration of the other blood proteins. Here, we show that a sandwich assay that combines mechanical and optoplasmonic transduction can detect cancer biomarkers in serum at ultralow concentrations. A biomarker is first recognized by a surface-anchored antibody and then by an antibody in solution that identifies a free region of the captured biomarker. This second antibody is tethered to a gold nanoparticle that acts as a mass and plasmonic label; the two signatures are detected by means of a silicon cantilever that serves as a mechanical resonator for 'weighing' the mass of the captured nanoparticles and as an optical cavity that boosts the plasmonic signal from the nanoparticles. The capabilities of the approach are illustrated with two cancer biomarkers: the carcinoembryonic antigen and the prostate specific antigen, which are currently in clinical use for the diagnosis, monitoring and prognosis of colon and prostate cancer, respectively. A detection limit of 1 × 10−16 g ml−1 in serum is achieved with both biomarkers, which is at least seven orders of magnitude lower than that achieved in routine clinical practice. Moreover, the rate of false positives and false negatives at this concentration is extremely low, ∼10−4. [ABSTRACT FROM AUTHOR]

Exchangeable organic carbon (OC) dynamics and CO2 fluxes in the Antarctic Peninsula region during austral summer are highly variable. By stations, the region is a weak source of CO2 to the atmosphere, however, continuous records of CO2 revealed this area as a weak sink. OC fluxes are also in both directions but generally towards the ocean and much higher than CO2 fluxes, sometimes by a factor of 10. Surface exchangeable dissolved organic carbon (EDOC) measurements had a 43±3 μmolCL-1 overall mean, while the gaseous organic carbon equilibrated in water as given by the Henry's Law constant (H') resulted in (GOC H'-1) concentrations of 46±3 μmolCL-1. EDOC represents around 66% of surface dissolved organic carbon (DOC) in Antarctic waters. There is a tendency towards low partial pressures of CO2 in waters with high Chlorophyll a (Chl a) content and high fCO2 in areas with high krill densities. However, such relationships were not found for EDOC. Depth profiles of EDOC were also quite variable and followed Chl a profiles, but only in some instances, while diel cycles of EDOC revealed two distinct peaks around midday and middle of the short austral dark period concurrent with solar radiation maxima and krill night migration patterns. However, there was no evident diel pattern for GOC H'-1. The pool of exchangeable OC reveals itself as an important compartment of the carbon budget in the Antarctic Peninsula and adds to previous studies highlighting its importance in the redistribution of carbon in marine environments. [ABSTRACT FROM AUTHOR]

The article presents several quiz related to diagnosis of a 66-year-old female presented with a long history of lower back pain, other of 59-year-old female complained of low back pain radiating to left leg and 28-year-old female presented with a long history of back pain.

We study optical back-action effects associated with confined electromagnetic modes in silicon nanowire resonators interacting with a laser beam used for interferometric read-out of the nanowire vibrations. Our analysis describes the resonance frequency shift produced in the nanowires by two different mechanisms: the temperature dependence of the nanowire's Young's modulus and the effect of radiation pressure. We find different regimes in which each effect dominates depending on the nanowire morphology and dimensions, resulting in either positive or negative frequency shifts. Our results also show that in some cases bolometric and radiation pressure effects can have opposite contributions so that their overall effect is greatly reduced. We conclude that Si nanowire resonators can be engineered for harnessing back-action effects for either optimizing frequency stability or exploiting dynamic phenomena such as parametric amplification. [ABSTRACT FROM AUTHOR]

We present an instrument based on the scanning of a laser beam and the measurement of the reflected beam deflection that enables the readout of arrays of nanomechanical systems without limitation in the geometry of the sample, with high sensitivity and a spatial resolution of few micrometers. The measurement of nanoscale deformations on surfaces of cm2 is performed automatically, with minimal need of user intervention for optical alignment. To exploit the capability of the instrument for high throughput biological and chemical sensing, we have designed and fabricated a two-dimensional array of 128 cantilevers. As a proof of concept, we measure the nanometer-scale bending of the 128 cantilevers, previously coated with a thin gold layer, induced by the adsorption and self-assembly on the gold surface of several self-assembled monolayers. The instrument is able to provide the static and dynamic responses of cantilevers with subnanometer resolution and at a rate of up to ten cantilevers per second. The instrumentation and the fabricated chip enable applications for the analysis of complex biological systems and for artificial olfaction. [ABSTRACT FROM AUTHOR]

Achilles tendon disorders are among the most common conditions seen by sports medicine physicians. The request for radiological assessment and for radiologically assisted therapy is on the steady increase. Thus understanding the anatomy and biomechanics of the Achilles tendon is crucial to the effective radiological diagnosis and thus the management of such conditions. [ABSTRACT FROM AUTHOR]

Background and purpose: The question whether patients with essential tremor (ET) have slowed movements as part of their clinical manifestations is still a matter of controversy. We analyzed basic motor function in patients with ET and in healthy matched controls. Methods: We studied 61 patients with ET and 122 age- and sex-matched controls. Evaluation included four timed tests (pronation-supination, finger tapping and movement between two points, all with both hands, and walking test); and three tests performed on a personal computer (speed for pressing repetitively a key – frequency, visual reaction time and movement time, all with both hands). Results: Essential tremor patients showed higher mean values for right and left finger tapping, left movement between two points; and with right and left frequency and reaction time. In the logistic regression study, ET patients showed significantly higher values than controls for right and left finger tapping; mean, SD, maximum and rank values of right and left frequency; and mean, SD, minimum, maximum and rank values of right and left visual reaction time. Tremor severity was not correlated with the altered values. Conclusions: Patients with ET showed impaired motor performance, at least in some tasks, such as rapid repetitive finger movements (finger tapping and frequency) and visual reaction time (impairment was not related with tremor severity). This probably means that patients with ET have some degree of bradykinesia. [ABSTRACT FROM AUTHOR]

Air-sea CO2 exchange depends on the air-sea CO2 gradient and the gas transfer velocity (k), computed as a function of wind speed. Large discrepancies among relationships predicting k from wind suggest that other processes also contribute significantly to modulate CO2 exchange. Here we report, on the basis of the relationship between the measured gas transfer velocity and the organic carbon concentration at the ocean surface, a significant role of surface organic matter in suppressing air-sea gas exchange, at low and intermediate winds, in the open ocean, confirming previous observations. The potential role of total surface organic matter concentration (TOC) on gas transfer velocity (k) was evaluated by direct measurements of air-sea CO2 fluxes at different wind speeds and locations in the open ocean. According to the results obtained, high surface organic matter contents may lead to lower air-sea CO2 fluxes, for a given air-sea CO2 partial pressure gradient and wind speed below 5 m s-1, compared to that observed at low organic matter contents. We found the bias in calculated gas fluxes resulting from neglecting TOC to co-vary geographically and seasonally with marine productivity. These results support previous evidences that consideration of the role of organic matter in modulating air-sea CO2 exchange may improve flux estimates and help avoid possible bias associated to variability in surface organic concentration across the ocean. [ABSTRACT FROM AUTHOR]

Air-sea CO2 exchange depends on the air-sea CO2 gradient and the gas transfer velocity (k), computed as a simple function of wind speed. Large discrepancies among relationships predicting k from wind suggest that other processes may also contribute significantly to modulate CO2 exchange. Here we report, on the basis of the relationship between the measured gas transfer velocity and the ocean surface organic carbon concentration at the ocean surface, a significant role of surface organic matter in suppressing air-sea gas exchange, at low and intermediate winds, in the open ocean. The potential role of total surface organic matter concentration (TOC) on gas transfer velocity (k) was evaluated by direct measurements of air-sea CO2 fluxes at different wind speeds and locations in the open ocean. According to the results obtained, high surface organic matter contents may lead to lower air-sea CO2 fluxes, for a given air-sea CO2 partial pressure gradient and wind speed below 5ms-1, compared to that observed at low organic matter contents. We found the bias in calculated gas fluxes resulting from neglecting TOC to co-vary geographically and seasonally with marine productivity. These findings suggest that consideration of the role of organic matter in modulating air-sea CO2 exchange can improve flux estimates and help avoid possible bias associated to variability in surface organic concentration across the ocean. [ABSTRACT FROM AUTHOR]

This study aimed to improve the modelling of flowering time in fruit trees and to understand to what extent global warming has affected this trait since the end of the 1980s. The onset of flowering time (F1 stage) in apple trees has advanced by 7 - 8 d in France since the late 1980s. In this context, a sequential model composed of a chilling sub-model and a heat sub-model was considered. The input data consisted of F1 dates for 'Golden Delicious' apple in three French cropping areas from the North-West to South-East over the period 1976 - 2002 (81 F1 dates). A user-oriented software package, called 'Pollenoscope', automatically optimised combinations between seven chilling and three heat temperature functions. This was achieved by maximizing the R2 values between the observed and simulated flowering dates. The study provided comparative information for assessing the respective effects of temperature functions commonly used for modelling flowering time in temperate trees. Three selected models explained 82 - 86% of the observed variability in flowering. Their fitness for an accurate prediction of the F1 date was validated using independent flowering datasets. All three models simulated similar time-course changes in the duration of the chilling effect at all three locations [i.e., a mean increase in the duration of this effect (by 3 - 5 d) since the end of the 1980s]. Consequently, it suggested that the duration of the heat effect had decreased (10 - 13 d) to explain the advance in flowering time. Hence, our results support the idea that global warming has, simultaneously, exerted two opposing effects in France between 1976 - 2002: (i) a slower mean rate of completion for the chilling requirement, and (ii) a higher mean rate of completion for the heat requirement. A more marked effect on completion of the heat requirement may have resulted from more pronounced warming from January to April, corresponding to the active growth phase of floral primordia, than from October to January, corresponding to the dormancy-breaking phase. [ABSTRACT FROM AUTHOR]

A series of dust pollen samples was collected along N-S transects in east China (18°N to 53°N latitudes). Sample sites extend from the cold-temperate zone in the north to the tropical region in the south. Pollen taxa characterize each region and reflect the natural and devastated vegetation as well as corresponding climatic zones. The quantitative pollen data can be used to estimate the spatial distribution of planted and introduced species. Valuable information of human disturbance of the natural forest is evaluated by quantitative comparison between dust pollen and in-situ pollen of protected forest. In addition, percentages of grass pollen vary regularly from north to south that is consistent with spatial distribution of net primary productivity in east China. Among all grasses, Artemisia and the Gramineae carry the clearest signal: their ratio increases northwards and therefore represent a suitable and convenient tool for palaeoclimate reconstructions. [ABSTRACT FROM AUTHOR]

We present the results of simulations, using density functional theory (DFT) with generalized gradient corrections (GGA), on the troilite (FeS), pyrrhotite (Fe1-xS) and MnP phases of FeS. The values obtained for the cell parameters and c / a ratio of troilite accurate to within 1% of those determined by experiment, a significant improvement on previous simulations. Energy–volume curves for FeS in the troilite and MnP structures indicate a pressure-induced transition at 4?GPa (experimentally observed at 3.4?GPa). Comparison of spin-polarised and non-spin-polarised simulations of the troilite structure demonstrate the significance of magnetostructural effects in determining the c / a ratio and shed light on the magnetic and volume collapse of FeS on its transition from the MnP to a monoclinic structure at 6.7?GPa. Simulations of different (001) surface terminations of troilite indicate that stable surfaces are characterised by triangles of iron atoms “capped” with a sulphur atom. [ABSTRACT FROM AUTHOR]

Collaboratories provide an environment where researchers at distant locations work together at tackling important scientific and industrial problems. In this paper we outline the tools and principles used to form the e Minerals collaboratory, and discuss the experience, from within, of working towards establishing the e Minerals project team as a functioning virtual organisation. Much of the emphasis of this paper is on experience with the IT tools. We introduce a new application sharing tool. [ABSTRACT FROM AUTHOR]

Computer modelling techniques were used to investigate the structures and stabilities of Li–K solid solutions of three different disilicate structures, employing a newly developed program based on symmetry arguments to identify identical configurations and hence eliminate unnecessary duplication of calculations. Even so, the large number of calculations needed to sample the complete set of configurations of a wide range of solid solutions necessitated the use of an extensive Condor pool of PC clusters, which afforded the necessary computing resources for this study. The results of our calculations show that in the wide range of Li–K solid solutions investigated, the mixed-cationic KLiSi2O5 material retains its original structure when the composition was varied, where six-membered rings of silica tetrahedra are linked to form continuous channels throughout the structure. The channel positions are found to be preferentially occupied by the potassium ions rather than by the smaller lithium ions. The original framework of the experimental K2Si2O5 structure, containing 14-membered rings of silica tetrahedra, similarly remains intact with the introduction of smaller lithium atoms into the bigger potassium lattice sites. However, the replacement of potassium ions for lithium ions in the Li2Si2O5 material causes significant distortions of the original structure, which loses its symmetry, although the ring structure remains. [ABSTRACT FROM AUTHOR]

We present the structural as well as elastic properties of the alkaline earth oxides and FeO, calculated using hybrid exchange functionals within DFT. We show that by empirically fitting the amount of Fock-exchange in the hybrid functionals, we can accurately reproduce the pressure-induced phase transitions for MgO, CaO, SrO and BaO. For FeO the hybrid functionals predict an insulator?metal transition at ca. 150?GPa, associated with an i-B8?B8 structural phase transition. The structural phase transition is accompanied by a spin transition from a high- to low-spin electron configuration on the Fe 2+ ions. Hence, FeO undergoes a magnetic phase transition from an anti-ferromagnetic to non-magnetic structure. We also find that as the ionicity of the polymorphs increases a higher fraction of Fock-exchange is required to reproduce the structural volumes reported from experiments. [ABSTRACT FROM AUTHOR]

This article describes the techniques and mechanisms that have been used to tackle workflow problems encountered in the e Minerals project. We examine how established tools and technologies can be brought together to specify and deploy a computational process , consisting of a set of jobs and tasks, on our production level mini-grid infrastructure, with respect to a specific problem—the distribution of calculations required to determine, in a systematic way, the mechanisms by which pollutant molecules such as DDT, dioxins and biphenyls, become bound to soil minerals. We also briefly discuss the use of data standards such as the Chemical Mark-up Language (CML) and web-service based grid standards as a means to facilitate workflow specification. [ABSTRACT FROM AUTHOR]

This paper describes a prototype grid infrastructure, called the “ e Minerals minigrid”, for molecular simulation scientists. which is based on an integration of shared compute and data resources. We describe the key components, namely the use of Condor pools, Linux/Unix clusters with PBS and IBM's LoadLeveller job handling tools, the use of Globus for security handling, the use of Condor-G tools for wrapping globus job submit commands, Condor's DAGman tool for handling workflow, the Storage Resource Broker for handling data, and the CCLRC dataportal and associated tools for both archiving data with metadata and making data available to other workers. [ABSTRACT FROM AUTHOR]

AlthoughCupressus sempervirenshas been spread over southern Europe since antiquity, cypress pollen allergy has not been reported until 1945 (). In France, the very first case reports were published in 1962 (). Since then, the prevalence of cypress pollinosis seems to demonstrate an upward trend, concomitantly with the increased use of cypress trees as ornamental plants, as wind breaks and as hedges. Hyposensitization, using improved pollen extracts, is increasingly prescribed. Besides, prevention measures begin to be implemented. Such measures include avoidance of planting new cypress trees, especially near human populations’ centres, trimming of cypress hedges before the pollination season and agronomical research for hypoallergenic trees. Altogether, such new developments in cypress allergy deserve an update review. [ABSTRACT FROM AUTHOR]

Floral nectars are rich in energy but contain only traces of amino acids, and it has been hypothesized that arthropods may be an important source of energy and amino acids for hummingbirds. We studied the nitrogen requirements of hummingbirds as well as how they use small arthropods to satisfy their nitrogen and energy requirements and how organ mass varies with nitrogen intake. Non-reproductive green-backed firecrowns Sephanoides sephaniodes were maintained for 10 days on diets containing 0%, 0.96%, 1.82%, 4.11% and 11.1% nitrogen (dry-matter basis). A second group of individuals were fed with varying amounts of nitrogen-free nectar supplemented with fruit flies. Finally, non-reproductive hummingbirds were captured as a control group for analysis of organ mass and size as well as fat content. The maintenance nitrogen requirement of green-backed firecrowus determined by regression was 1.42 mg N day[sup -1], yet they required nearly 10 mg N day[sup -1] to maintain body mass. When arthropods were available, we observed that hummingbirds required approximately 150 fruit flies to maintain body mass, which corresponds to a 5% nitrogen diet. Interestingly, when nectar was restricted (to 4 ml day[sup -1]), or was absent, arthropods alone were not able to satisfy the body mass balance requirements of hummingbirds, suggesting that arthropods are not adequate as an energy source. In the group offered an 11.1% nitrogen diet, the size and surface of the small intestine, and liver and kidney mass increased in comparison with the control group (non-reproductive field hummingbirds) or the nitrogen-free group, suggesting a nitrogen overload. Our results are in agreement with other studies showing low nitrogen requirements by nectarivores. An important point to stress is that nitrogen digestibility declined in the 11.1% nitrogen diet, which strongly supports our nitrogen absorption saturation hypothesis. [ABSTRACT FROM AUTHOR]

The mechanisms involved in the regulation of mitochondrial DNA (mtDNA) replication, a process that is crucial for mitochondrial biogenesis, are not well understood. In this study, we evaluate the role of DNA polymerase γ (pol γ), the key enzyme in mtDNA replication, in both Drosophila cell culture and in developing flies. We report that overexpression of the pol γ catalytic subunit (pol γ-α) in cultured Schneider cells does not alter either the amount of mtDNA or the growth rate of the culture. The polypeptide is properly targeted to mitochondria, yet the large excess of pol γ-α does not interfere with mtDNA replication under these conditions where the endogenous polypeptide is apparently present in amounts that exceed of the demand for its function in the cell. In striking contrast, overexpression of pol γ-α at the same level in transgenic flies interferes with the mtDNA replication process, presumably by altering the mechanism of DNA synthesis, suggesting differential requirements for, and/or regulation of, mtDNA replication in Drosophila cell culture versus the developing organism. Overexpression of pol γ-α in transgenic flies produces a significant depletion of mtDNA that causes a broad variety of phenotypic effects. These alterations range from pupal lethality to moderate morphological abnormalities in adults, depending on the level and temporal pattern of overexpression. Our results demonstrate that although cells may tolerate a variable amount of the pol γ catalytic subunit under some conditions, its level may be critical in the context of the whole organism. [ABSTRACT FROM AUTHOR]

Presents a study which examined the role of gastrolites on feeding behavior and digestive efficiency in the Rufous-collared Sparrow. Methodology; Results; Discussion.

Features a study which examined the feeding behavior and nutritional ecology of Rufous-tailed Plantcutter or Phytotoma rara, one of the smallest species of avian herbivores. Methodology; Diet and feeding preferences; Roles of experimental diets on body mass change, intake and apparent digestibility.

Presents information on a study which examined the activity of three intestinal membrane-bound digestive enzymes in rufous-tailed plantcutter. Impact of the study on avian intestinal biochemistry; Results; Discussion.

A previous two-parameter model of a molecular fluid is extended to three parameters and applied to a fluid of hard ellipsoids with restricted orientations. The direct correlation function of the fluid is written as a linear combination of three basic functions derived from the geometry of two molecules and the coefficients determined from algebraic equations also satisfied by the Percus-Yevick (PY) solution of the problem. The theory yields the PY solution and PY equation of state in the special case of hard spheres. For ellipsoids the equation of state agrees better with the results of computer simulation than the two-parameter version although the discrepancy increases with increasing anisotropy of the molecules. According to the model the fluid makes a transition to a nematic state although the predicted densities at which the transition takes place are too low. [ABSTRACT FROM AUTHOR]

Despite the biological relevance, the physical origin of attraction between highly negatively charged DNA strands in condensation remains an open question. We have used microcantilever sensors to study the forces involved in DNA condensation by spermidine. The experiments were performed under flow conditions with gold-coated cantilevers sensitized with thiolated single stranded DNA. The experiments show that above a critical concentration of spermidine, the DNA strands abruptly experiences large attractive forces. The critical spermidine concentration for the transition increases with the monovalent salt concentration. The experiments provide a direct insight of the forces responsible of condensation. [ABSTRACT FROM AUTHOR]