Photometry and spectroscopy of faint candidate spectrophotometric standard DA white dwarfs

We present precise photometry and spectroscopy for 23 candidate spectrophotometric standard white dwarfs. The selected stars are distributed in the Northern hemisphere and around the celestial equators and are all fainter than r ~ 16.5 mag. This network of stars, when established as standards, together with the three Hubble Space Telescope primary CALSPEC white dwarfs, will provide a set of spectrophotometric standards to directly calibrate data products to better than 1%. These new faint standard white dwarfs will have enough signal-to-noise ratio in future deep photometric surveys and facilities to be measured accurately while still avoiding saturation in such surveys. They will also fall within the dynamic range of large telescopes and their instruments for the foreseeable future. This paper discusses the provenance of the observational data for our candidate standard stars. The comparison with models, reconciliation with reddening, and the consequent derivation of the full spectral energy density distributions for each of them is reserved for a subsequent paper.Comment: 31 pages, 17 figures, 10 tables, ApJ in press (accepted on December 23rd, 2018

Anisotropic Ni–Fe–B films with varying alloy composition for high frequency magnetics on silicon applications

An electroless nickel-iron alloy deposition process utilizing an external magnetic field was studied to achieve varying nickel and iron compositions for the specific high frequency application range. High anisotropy, low coercivity and high saturation flux density values were achieved which show significant improvements appropriate for high frequency magnetics on silicon applications. It has been shown that higher Fe content films can be achieved by increasing the DMAB concentration. The magnetic, electrical and structural characteristics of these application specific films with different Fe content were reported. The increased resistivity of the films reduces the eddy current losses whereas the permeability studies suggests high frequency applicability of the thin films as core material in magnetics on Si applications. The micro-structural analyses suggested that the deposits are nano-crystalline in nature with grain sizes below 33 nm resulting in low coercivity values in the films. The pH value is compatible with standard photoresists used in silicon based microfabrication processes

Competence Checking for the Global E-Service Society Using Games

We study the problem of checking the competence of communicative agents operating in a global society in order to receive and offer electronic services. Such a society will be composed of local sub-societies that will often be semi-open, viz., entrance of agents in a semi-open society is conditional to specific admission criteria. Assuming that a candidate agent provides an abstract description of their communicative skills, we present a test that a controller agent could perform in order to decide if a candidate agent should be admitted. We formulate this test by revisiting an existing knowledge representation framework based on games specified as extended logic programs. The resulting framework finds useful application in complex and inter-operable web-services construed as semi-open societies in support of the global vision known as the Semantic Web

Characterization of maize physiological responses to nitrogen stress by using chlorophyll fluorescence and gas exchange measurements.

Suplemento. Edição dos resumos do IX Congresso Brasileiro de Fisiologia Vegetal, 2003, Atibaia, SP

Quark mass dependence of hadron masses from lattice QCD

We discuss lattice methods to obtain the derivatives of a lattice meson mass with respect to the bare sea and valence quark masses. Applications are made to quenched and dynamical fermion configurations. We find evidence for significant differences between quenched and dynamical fermion configurations. We discuss how to relate dependence on the bare lattice parameters to more phenomenologically useful quantities.Comment: 18 pages, 5 figures, typos fixed and reference adde

Ruminant Agriculture: A Tool for Climate Change Mitigation

The quest to address and mitigate climate change has been dubbed a “wicked problem” as it involves many interconnected processes requiring a multifaceted, comprehensive approach. Animal agriculture contributes roughly 15% to CO2 equivalent (CO2e) emissions; as a result, a concerted effort is being made to develop and promote more climate-friendly production practices. These practices include species diversification in grasslands, improving grazing rotation, adding nitrogen amendments, and the use of feed additives to reduce enteric fermentation. Successful inter-seeding of legumes and deep-rooted native grasses increases soil organic carbon (SOC) pools in many systems by increasing the biological carbon inputs to the rhizosphere. Rotational grazing increases the concentration of ruminant waste in smaller areas resulting in a more uniform application of nutrients and forage use. The rotational grazed pasture allows for longer pasture recovery, thereby increasing SOC stocks indirectly through increased root and aboveground biomass growth. Fertilization of pasturelands with nitrogen-only fertilizers increases SOC stocks. Enteric methane emission makes up over 44% of animal agriculture’s carbon footprint (Tubiello et al. 2013) and can be reduced using novel feed additives to mixed rations for confined cattle consumption. It’s important to consider that none of these management practices is a silver bullet that works in any situation; instead, these can be effective tools to draw down carbon emissions. Many barriers, particularly financial ones, have kept land managers from implementing these climate-improving practices. To help growers address these barriers to adoption Agoro Carbon™ Alliance is implementing carbon offset projects, which provide both financial incentives and education that facilitate the adoption of multiple, improved agricultural management practices involving animal agriculture

Desenvolvimento de um algoritmo baseado em sensores ativos de dossel para recomendação da adubação nitrogenada em taxas variáveis.

O uso de sensores ativos de dossel (ACS) para o ajuste da aplicação localizada em tempo real de fertilizantes nitrogenados é promissor na região do Cerrado, onde grande quantidade de fertilizantes à base de nitrogênio (N) são aplicados em doses uniformes. A vantagem desta técnica comparada com a aplicação tradicional em dose uniforme é principalmente na sincronia da aplicação do N com a época ideal de absorção do nutriente pela planta no decurso da cultura considerando a variabilidade espacial. O objetivo deste estudo foi a geração de um primeiro algoritmo para cálculo da dose de N em milho baseado em leituras destes ACS na região do Cerrado. O experimento foi conduzido em fazenda em 7 locais (durante as safras 2010 e 2011), utilizando faixas longas experimentais com diferentes doses de N (0, 72, 144, 216, 288 and 360 kg N ha-1) com três repetições. Cada uma consistiu de uma faixa de 500m de comprimento em sistema de plantio direto em sequeiro. As medições com os sensores foram realizadas entre os estádios fenológicos de V11 e V13 utilizando um sensor ativo de três bandas (infravermelho próximo, vermelho e vermelho próximo) e um clorofilômetro portátil. A produtividade de grãos foi medida com colhedoras equipadas com monitores de produtividade e DGPS. Foi possível a geração de um primeiro algoritmo para utilização no segundo estágio do projeto, onde serão realizadas as validações comparando com outros procedimentos e abordagens para manejo localizado de N

Calculation of K→πK\to \pi matrix elements in quenched domain-wall QCD

We explore the possibility for an evaluation of non-leptonic $\Delta S=1$ $K$ decay amplitudes through the calculation of $K\to\pi$ matrix elements using domain-wall QCD. The relation between the physical $K\to\pi\pi$ matrix elements and $K\to\pi$ matrix elements deduced from chiral perturbation theory is recapitulated. Quenched numerical simulations are performed on an $16^3\times 32\times 16$ lattice at a lattice spacing $a^{-1}\approx 2$GeV for both the standard plaquette gauge action and a renormalization-group improved gauge action, and reasonable signals for $K\to\pi$ matrix elements are obtained. Preliminary results are reported on the $K\to\pi\pi$ matrix elements, and results from two actions are compared.Comment: Lattice 2000 (Hadronic Matrix Elements), 4 pages, 8 figures, Addresses of the author was revise

Empirical evidence for discrete neurocognitive subgroups in bipolar disorder: clinical implications

Background. Recent data suggest trait-like neurocognitive impairments in bipolar disorder (BPD), with deficits about 1 S.D. below average, less severe than deficits noted in schizophrenia. The frequency of significant impairment in BPD is approximately 60%, with 40% of patients characterized as cognitively spared. This contrasts with a more homogeneous presentation in schizophrenia. It is not understood why some BPD patients develop deficits while others do not. Method. A total of 136 patients with BPD completed the MATRICS Consensus Cognitive Battery and data were entered into hierarchical cluster analyses to: (1) determine the optimal number of clusters (subgroups) that fit the sample; and (2) assign subjects to a specific cluster based on individual profiles. We then compared subgroups on several clinical factors and real-world community functioning. Results. Three distinct neurocognitive subgroups were found: (1) an intact group with performance comparable with healthy controls on all domains but with superior social cognition; (2) a selective impairment group with moderate deficits on processing speed, attention, verbal learning and social cognition and normal functioning in other domains; and (3) a global impairment group with severe deficits across all cognitive domains comparable with deficits in schizophrenia. Conclusions. These results suggest the presence of multiple cognitive subgroups in BPD with unique profiles and begin to address the relationships between these subgroups, several clinical factors and functional outcome. Next steps will include using these data to help guide future efforts to target these disabling symptoms with treatment