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The recycling of scarce nutrient resources in the sunlit open ocean is crucial to ecosystem function. Nitrification directs ammonium (NH4+) derived from organic matter decomposition towards the regeneration of nitrate (NO3-), an important resource for photosynthetic primary producers. However, the technical challenge of making nitrification rate measurements in oligotrophic conditions combined with the remote nature of these environments means that data availability, and the understanding that provides, is limited. This study reports nitrite (NO2-) regeneration rate (RNO2 – the first product of nitrification derived from NH4+ oxidation) over a 13 000 km transect within the photic zone of the Atlantic Ocean. These measurements, at relatively high resolution (order 300 km), permit the examination of interactions between RNO2 and environmental conditions that may warrant explicit development in model descriptions. At all locations we report measurable RNO2 with significant variability between and within Atlantic provinces. Statistical analysis indicated significant correlative structure between RNO2 and ecosystem variables, explaining ∼65 % of the data variability. Differences between sampling depths were of the same magnitude as or greater than horizontally resolved differences, identifying distinct biogeochemical niches between depth horizons. The best overall match between RNO2 and environmental variables combined chlorophyll-a concentration, light-phase duration, and silicate concentration (representing a short-term tracer of water column physical instability). On this basis we hypothesize that RNO2 is related to the short-term autotrophic production and heterotrophic decomposition of dissolved organic nitrogen (DON), which regenerates NH4+ and supports NH4+ oxidation. However, this did not explain the observation that RNO2 in the deep euphotic zone was significantly greater in the Southern Hemisphere compared to the Northern Hemisphere. We present the complimentary hypothesis that observations reflect the difference in DON concentration supplied by lateral transport into the gyre interior from the Atlantic's eastern boundary upwelling ecosystems.

Background Lung cancer risk prediction models do not routinely incorporate imaging metrics available on low-dose CT (LDCT) imaging of the chest ordered for lung cancer screening. Research Question What is the association between quantitative emphysema measured on LDCT imaging and lung cancer incidence and mortality, all-cause mortality, and airflow obstruction in individuals who currently or formerly smoked and are undergoing lung cancer screening? Study Design and Methods In 7,262 participants in the CT arm of the National Lung Screening Trial, percent low attenuation area (%LAA) was defined as the percentage of lung volume with voxels less than –950 Hounsfield units on the baseline examination. Multivariable Cox proportional hazards models, adjusting for competing risks where appropriate, were built to test for association between %LAA and lung cancer incidence, lung cancer mortality, and all-cause mortality with censoring at 6 years. In addition, multivariable logistic regression models were built to test the cross-sectional association between %LAA and airflow obstruction on spirometry, which was available in 2,700 participants. Results The median %LAA was 0.8% (interquartile range, 0.2%-2.7%). Every 1% increase in %LAA was independently associated with higher hazards of lung cancer incidence (hazard ratio [HR], 1.02; 95% CI, 1.01-1.03; P = .004), lung cancer mortality (HR, 1.02; 95% CI, 1.00-1.05; P = .045), and all-cause mortality (HR, 1.01; 95% CI, 1.00-1.03; P = .042). Among participants with spirometry, 892 had airflow obstruction. The likelihood of airflow obstruction increased with every 1% increase in %LAA (odds ratio, 1.07; 95% CI, 1.06-1.09; P 65 years. Interpretation Quantitative emphysema measured on LDCT imaging of the chest can be leveraged to improve lung cancer risk prediction and help diagnose COPD in individuals who currently or formerly smoked and are undergoing lung cancer screening.

The electromagnetic field confinement and amplification typical of nano-sized metallic objects supporting localized surface plasmon resonances, i.e., light-induced collective electronic oscillations, can significantly strengthen the interaction of light with atomically thin transition metal dichalcogenides. In view of the realization of plasmon-enhanced devices, it is crucial to investigate the effects induced by light confinement within metallic nanostructures on the excitonic properties of these materials at the nanoscale. Here, we exploit tip-enhanced photoluminescence spectroscopy to locally control the excitons of monolayer molybdenum disulfide (MoS2) coupled with gold nanotriangles in the quantum tunneling regime. The spatial resolution of 10 nm in the tip-enhanced photoluminescence measurements made it possible to image the light-emission related properties of monolayer MoS2 across one single metallic nanostructure and to investigate the effect of the plasmonic enhancement on its photoluminescence peak. Moreover, by taking advantage of the degree of freedom given by the tuning of the tip-sample distance; it was possible to probe the effect of the plasmonic pico-cavity size on the photoluminescence quenching rate of monolayer MoS2.

Chronic obstructive pulmonary disease (COPD) is a common respiratory disorder with significant morbidity and mortality. Despite its prevalence, COPD is underdiagnosed, and many patients do not receive a diagnosis until the disease is clinically advanced. Recent basic science and clinical research have focused on the early physiologic and pathobiologic changes in COPD with the hopes of improving diagnosis, providing targets for disease-modifying therapy, and identifying patients most likely to benefit from early intervention. Available treatments for COPD have grown substantially in the past 20 years with the introduction of new oral and inhaled medications as well as novel surgical and bronchoscopic procedures. This article summarizes some of the recent advances in our understanding of disease pathogenesis and treatment paradigms.

Batan Bay and Tinago Lake are shallow embayments connected to each other, located on the north of Panay Island, central Philippines (11.53° – 11.67°N, 122.38° – 122.52°E). Although ...

To further understand dissolved carbon dioxide (CO 2 ) dynamics and the link between surface productivity and carbon content in the sediments of the Sulu Sea, seawater samples were obtained from high and low productivity areas during the northeast monsoon of December 2007/January 2008, which also corresponded to a period of weak La Nina. CO 2 concentrations in surface waters of the Sulu Sea are mostly governed by productivity, while sub-surface CO 2 concentrations are influenced by physical processes including vertical mixing and bottom-intensified flow southwest of Mindoro and Panay Straits (central Philippines), and upwelling off the west coast of Zamboanga in Mindanao (south Philippines). These physical processes are manifested in the downward sloping isolines of carbonate parameters near the straits and weak upwelling of waters saturated with respect to atmospheric CO 2 . Deep waters ventilated from the Sulu Sea have lower dissolved inorganic carbon (DIC) and total alkalinity (TA), and higher pH T (pH in the total scale) and carbonate ion concentrations (CO 3 2 − ) than the deep waters of the South China Sea. Nevertheless, TA in the deep waters of the Sulu Sea increases below 2000 m at almost twice the rate as DIC, suggesting possible dissolution of sedimentary CaCO 3 . A small positive “excess” alkalinity signal is observed in the South China Sea but negative values in the Sulu Sea may reflect the possible contribution of organic acids. This study suggests that the upwelling area within the Sulu Sea, albeit limited in size, could be a source of CO 2 to the atmosphere especially during the stronger northeast monsoon periods. Other processes such as dissolution of CaCO 3 in the sediments and possible organic acidity should be considered in understanding the Sulu Sea's CO 2 sink capacity for the coming years.

In this work, we present a complete multiphysics modelling (via the Finite Element Method, FEM) of an air coupled piezoelectric micromachined ultrasonic transducer (PMUT) with preliminary experimental validations. The PMUT is a suspended layered membrane, in which one of the layers is made of piezoelectric material. By means of an applied voltage over the piezoelectric layer thickness, the device emits acoustic waves in air. The model takes into account the multiple interactions between electrical, mechanical and acoustic fields, and in particular gives a realistic estimation of the device quality factor by means of a proper modelling of thermo-viscous losses in the fluid domain. The complexity of the model is increased by the presence of initial large deformations in the membrane and fabrication induced residual stresses. Preliminary experimental matchings are presented for static pre-deflection of the membrane due to residual stresses and for the eigenfrequency corresponding to acoustic wave emission.

In this paper a complete Multiphysics modelling via the Finite Element Method (FEM) of an air-coupled Piezoelectric Micromachined Ultrasonic Transducer (PMUT) is described, with its experimental validation related to the mechanical and acoustic responses.

Towards the fabrication of all-dielectric nanophotonic devices with tunable capabilities, we combined interband and intraband nonlinearities in aluminum-doped zinc oxide thin films thus enlarging the material bandwidth and gaining ultra-fast control over the transmitted spectrum.

The sequestration of anthropogenic carbon dioxide in the form of organic carbon and its eventual deposition in the sediments is an important component of the marine carbon cycle. In the Sulu Sea, Philippines, organic carbon contents in the sediments have been relatively well studied, but the processes that describe the organic carbon distributions in the water column have not been elucidated. Dissolved and particulate organic carbon (DOC, POC) concentrations were measured at several stations in the Sulu Sea during the northeast monsoon of 2007/2008 to understand the dynamics of organic carbon in this unique internal sea. Analyses of primary productivity estimates, beam attenuation coefficient (at 660 nm) profiles, and correlation coefficients among DOC, POC and other parameters (e.g., apparent oxygen utilization) at different layers of the water column indicate that surface primary productivity, upwelling, bottom intensified flows across sills, and ventilation from shallow sills, which may contain semi-labile DOC that is estimated to largely contribute to microbial respiration in the bathypelagic layer, are the major processes that affect the DOC and POC distributions in the Sulu Sea. The variability of these processes should be taken into consideration when assessing the sustainability of internal and marginal seas as carbon sinks.

We introduce an innovative geometry for OPOs in a CMOS-compatible microring resonator that is robust against the effect of thermal fluctuations. It exploits lasing of the pump inherently positioned within the resonances of the microcavity.

– The reported case concerns an unusual localisation of “Royal Tumour” connected with von Recklinghausen's neurofibromatosis. Surgery was necessary because of the increasing difficulty of the patient in having sexual relations due to the progressive swelling of the penile neoformation. The typical clinical picture, the integrity of the corpora cavernosa and the negative impact of the neoformation on the patient's sexual life all indicated the necessity for operation. Results were satisfactory both surgically and functionally/aesthetically and the patient regained normal sexual activity.

The authors describe a new technique for the delayed repair of iatrogenic WF using the fibrous tissue around the fistula as a support for the suture of the bladder muscular wall. The results obtained on five patients are reported.

A set of rotational test structures for on-chip fracture characterization of 0.7 /spl mu/m thick polysilicon film have been designed, modeled and fabricated. The structures are actuated by a large number of comb-fingers capacitors which develop a force sufficient to load the specimens in bending up to rupture. A 3D FE model of the whole structures was used during the design phase. Tests were carried out at room temperature and at atmospheric humidity. The measured Young modulus of the tested polysilicon was 182/spl plusmn/9 GPa. The low dispersion around the mean value confirms the quality and the good reliability of the whole procedure. Rupture stresses computed after the application of Weibull theory were 1875/spl plusmn/333 MPa.

The initiation of graft vs. host disease (GVHD) after stem cell transplantation is dependent on direct antigen presentation by host antigen presenting cells (APC) while the effect of indirect antigen presentation by donor APC is unknown. We have studied the role of indirect antigen presentation in allogenic responses by adding populations of cytokine-expanded donor APC to haematopoietic grafts that would otherwise induce lethal GVHD. Progenipoietin-1 (a synthetic G-CSF/Flt-3 L molecule) and G-CSF expanded myeloid DC, plasmacytoid DC and a novel granulocyte-monocyte precursor population (GM) that differentiate into class IIpos, CD80/CD86pos, CD40neg APC during GVHD. Whereas addition of plasmacytoid and myeloid donor DC augmented GVHD, GM cells induced transplant tolerance via MHC class II restricted generation of IL-10-secreting regulatory T cells. Thus a population of cytokine expanded granulocyte-monocyte precursors function as regulatory antigen presenting cells, suggesting that G-CSF derivatives may have application in disorders characterised by a loss of self-tolerance.

To analyse participation levels in a family planning survey.Descriptive and sectorial survey by means of personal interviews. SITE. Primary Care. Rural Context. Basic Health Area of Sanlúcar la Mayor (Sevilla).271 women of child-bearing age (15 to 49) chosen at random from the Municipal Census, who were invited by letter to the place of work of those doing the survey.Those who did not attend were invited on two further occasions.The level of reply was 24.8% of those invited by the first letter, 25.12% by the second and 28.9% by the third. 40% of the total number did not attend on any of the three occasions: in 29.9% of cases because of work or study; in 22.9% because they hadn't received the letter; in 18.1% because of another commitment; in 26.5% due to lack of interest; 6% due to absence; and 3.6% owing to other reasons. 72.3% had no School Graduation Certificate. Only 10.3% were working. Differences of age, level of studies achieved and work activity between those attending and those not attending were considered significant but of no overall relevance.A survey based on personal interviews is a useful and valid way of collecting information in a rural community. Poor participation is thought to be due to both the low social and cultural levels and to the survey's subjects-matter. We consider that sending follow-up letters of invitation is a sound method of reducing as much as possible the number of home interviews which would otherwise have to be administered to those who did not attend.

We report the first evidence of stimulated emission in photopumped modulation doped GaInAs/AlInAs multiple quantum wells (MDQWs) emitting in the technologically important 1.3–1.5 μm wavelength region. The modulation doped heterostructures exhibit higher performances and optical gain as compared to identical undoped quantum wells. The recombination mechanism in the MDQWs is interpreted in terms of a photoinduced switching from a one- to a two-component carrier plasma.

This study summarizes a portion of the validation data used in the development of CLASS.LD2, an expert system for classifying learning disabled students. Two hundred sixty-four students files were evaluated using CLASS.LD. There was disagreement between the multidisciplinary teams and CLASS.LD2 in 78 cases. These 78 cases were then submitted to three experts in LD classification. These experts were asked to make eligibility decisions for each of the 78 cases. Their decisions were compared to those of the expert system and the placement teams. The data from these comparisons suggested that (a) CLASS. LD2 was in agreement with the experts more often than were the placement teams, (b) the expert system's decisions were significantly correlated with those of the experts, and (c) in those cases in which the experts were in unanimous disagreement with CLASS.LD2, it was shown that CLASS.LD2 conformed strictly to state rules and regulations in making its eligibility decisions.

Skin electrical impedance parameters have been calculated in 15 hemiplegic subjects and in 10 healty subjects in order to evaluate differences before and after physiokynesitheraphy. The first result put in evidence a significant reduction in the impedance of the hemiplegic subjects in comparison with normal subjects; after physiokinesitheraphy the values tend to become more like the normal ones. On the contrary, till now significant skin impedance differences between ill and healty side have not been registered.

A new MEMS for on-chip mechanical testing of 0.9 /spl mu/m thick polysilicon film has been designed, modelled and fabricated. The polysilicon film is electrostatically loaded under bending until rupture in the out of plane direction, by means of electrostatic attraction in the direction orthogonal to the substrate. This is at difference with previous works of the same authors, in which results relevant to in plane loading conditions have been presented. 3D finite element (FE) and boundary element (BE) models of the structure were used during the design and data reduction phases. Tests were carried out at room temperature and at atmospheric humidity. The measured Young modulus of the tested polysilicon was 169 /spl plusmn/ 11 GPa. Rupture stress computed after the application of Weibull theory was 5669 MPa, with a Weibull modulus m = 22.5.

A set of rotational test structures for on-chip fracture characterization of 0.7 ,urn thick polysilicon film have been designed, modeled and fabricated. The structures are actuated by a large number of comb-fingers capacitors which develop a force sufficient to load the specimens in bending up to rupture. A 3D FE model of the whole structures was used during the design phase. Tests were carried out at room temperature and at atmospheric humidity. The measured Young modulus of the tested polysilicon was 182 & 9 GPa. The low dispersion around the mean value confirms the quality and the good reliability of the whole procedure. Rupture stresses computed after the application of Weibull theory were 1875 f 333 MPa.

It is often claimed that in normative political theory political imagination should remain unaffected by real-world contingencies: our idea of how the world “ought to be” should be independent from how the world “actually is”. According to the practice-dependent thesis, instead, “[t]he content, scope, and justification of a conception of justice depends on the structure and form of the practices that the conception is intended to govern” (Sangiovanni 2008). This methodological approach conceives the relationship between theory and practice as an interplay: normative theory applies to practice, but practices are also able to affect the content of normative theory. In this paper, I argue that the interplay between theory and practices that the practice-dependent method generates has not been fully understood. Though it may – at a superficial look – appear as a method compliant with the status quo, I will show that this method implies an idea of political theory as an activity of continuous critical engagement. Given an extended account of the method, political imagination has boundaries but these are not fixed nor easily-definable: the real-world fact that constrains practice-dependent principles is the point and purpose of the practice they are meant to apply to, but this fact in itself is partly shaped and critically assessed by the theorist.