Serial assessment of the electrocardiographic strain pattern for prediction of new‐onset heart failure during antihypertensive treatment: the LIFE study

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/106144/1/ejhfhfq224.pd

Modeling Land-Cover Types Using Multiple Endmember Spectral Mixture Analysis in a Desert City

Spectral mixture analysis is probably the most commonly used approach among sub-pixel analysis techniques. This method models pixel spectra as a linear combination of spectral signatures from two or more ground components. However, spectral mixture analysis does not account for the absence of one of the surface features or spectral variation within pure materials since it utilizes an invariable set of surface features. Multiple endmember spectral mixture analysis (MESMA), which addresses these issues by allowing endmembers to vary on a per pixel basis, was employed in this study to model Landsat ETM+ reflectance in the Phoenix metropolitan area. Image endmember spectra of vegetation, soils, and impervious surfaces were collected with the use of a fine resolution Quickbird image and the pixel purity index. This study employed 204 (=3x17x4) total four-endmember models for the urban subset and 96 (=6x6x2x4) total five-endmember models for the non-urban subset to identify fractions of soil, impervious surface, vegetation, and shade. The Pearson correlation between the fraction outputs from MESMA and reference data from Quickbird 60 cm resolution data for soil, impervious, and vegetation were 0.8030, 0.8632, and 0.8496 respectively. Results from this study suggest that the MESMA approach is effective in mapping urban land covers in desert cities at sub- pixel level.

Multiculturalismo e femminismo. Il multiculturalismo danneggia le donne?

Traduzione di Maria Chiara Pievatol

Combined Effects of Impervious Surface and Vegetation Cover on Air Temperature Variations in a Rapidly Expanding Desert City

The goal of this study is to improve our understanding of the interac- tive function of impervious and vegetation covers at different levels of the local and intra-urban spatial scales in relation to air temperatures in an urban environment. A multiple regression model was developed using impervious and vegetation frac- tions at different scales to predict maximum air temperature for the entire Phoenix metropolitan area in Arizona, USA. This study demonstrates that a small amount of impervious cover in a desert city can still increase maximum air temperature despite abundant vegetation cover.

A Kantian Critique Of The Care Tradition: Family Law And Systemic Justice

Liberal theories of justice have been rightly criticized for two things by care theorists. First, they have failed to deal with private care relations’ inherent dependency, asymmetry and particularity. Second, they have been shown unable properly to address the asymmetry and dependency constitutive of care workers’ and care-receivers’ systemic conditions. I apply Kant’s theory of right to show that current care theories unfortunately reproduce similar problems because they also argue on the assumption that good care requires only virtuous private individuals. Giving up this assumption enables us to solve the problems regarding both private care relations and systemic injustice

Heart rate adjustment of the time-voltage ST segment integral: Identification of coronary disease and relation to standard and heart rate-adjusted ST segment depression criteria

AbstractTo assess the effect of heart rate adjustment of the magnitude of the ST integral (ST-HR integral) on exercise test performance, the exercise electrocardiogram (ECG) of 50 clinically normal subjects and 100 patients with known or suspected coronary artery disease was analyzed. At matched specificity of 96% with standard ECG criteria (≥0.1 mV of additional horizontal or downsloping ST segment depression), ar unadjusted ST integral partition of 16 μV-s identified coronary disease in the 100 patients with known or suspected disease with a sensitivity of only 41%, a value significantly lower than the 59% sensitivity of standard ECG criteria (p < 0.01) and the 65% sensitivity of an ST depression partition of 130 μV (p < 0.001).However, test performance of the ST integral was greatly improved by simple heart rate adjustment: at a matched specificity of 96%, an ST-HR integral partition of 0.154 μV-s/beat per min identified coronary disease in the 100 patients with a sensitivity of 90%, a value significantly greater than the 59% sensitivity of standard criteria and 65% sensitivity of ST depression criteria (each p < 0.001) and similar to the 91% sensitivity of the ST-HR index and 93% sensitivity of the ST-HR slope (each p = NS). Comparison of receiver-operating characteristic curves confirmed the superior overall test performance of the ST-HR integral relative to the ST integral and ST segment depression, and demonstrated improved performance that was comparable with that of the ST-HR index and the ST-HR slope.These findings support the value of heart rate adjustment of end-exercise repolarization changes during exercise electrocardiography and demonstrate that this approach significantly improves the performance of the ST integral in identifying coronary artery disease

The interactive nutrient and water effects on vegetation biomass at two African savanna sites with different mean annual precipitation

Author's manuscript made available in accordance with the publisher's policy.Savannahs cover more than 40% of Africa and provide a variety of important ecosystem services. Their productivity is constrained by disturbance and limiting resources. In southern Africa, fine-leaf savannahs typical of arid environments are known for being richer in nutrients than broad-leaf mesic savannahs. However, despite numerous recent studies on the dynamics of southern African savannahs, the interplay between water and nutrient limitations remains poorly investigated in these systems. To better understand the interactions between water, nutrients (N and P in this manuscript) and grazing on the productivity of grasses and trees in fine-leaf savannah ecosystems, a fertilization experiment with controlled grazing was conducted at two sites with different mean annual rainfall in Namibia. The experiment demonstrated that the vegetation at the drier site may not be nutrient-limited (N, P or N + P). At the wetter site, however, vegetation showed significant response to nutrient addition. Grasses exhibited N limitation and trees exhibited P limitation. This experiment also showed that grazing reduces the overall grass biomass, but may not modify the response to nutrient treatments. The results indicated a switch from water to nutrient limitation between dry and wet sites and demonstrated different tree and grass responses to nutrient additions

Asynchronous Response of Tropical Forest Leaf Phenology to Seasonal and El Niño-Driven Drought

The Hawaiian Islands are an ideal location to study the response of tropical forests to climate variability because of their extreme isolation in the middle of the Pacific, which makes them especially sensitive to El Niño-Southern Oscillation (ENSO). Most research examining the response of tropical forests to drought or El Niño have focused on rainforests, however, tropical dry forests cover a large area of the tropics and may respond very differently than rainforests. We use satellite-derived Normalized Difference Vegetation Index (NDVI) from February 2000-February 2009 to show that rainforests and dry forests in the Hawaiian Islands exhibit asynchronous responses in leaf phenology to seasonal and El Niño-driven drought. Dry forest NDVI was more tightly coupled with precipitation compared to rainforest NDVI. Rainforest cloud frequency was negatively correlated with the degree of asynchronicity (ΔNDVI) between forest types, most strongly at a 1-month lag. Rainforest green-up and dry forest brown-down was particularly apparent during the 2002–003 El Niño. The spatial pattern of NDVI response to the NINO 3.4 Sea Surface Temperature (SST) index during 2002–2003 showed that the leeward side exhibited significant negative correlations to increased SSTs, whereas the windward side exhibited significant positive correlations to increased SSTs, most evident at an 8 to 9-month lag. This study demonstrates that different tropical forest types exhibit asynchronous responses to seasonal and El Niño-driven drought, and suggests that mechanisms controlling dry forest leaf phenology are related to water-limitation, whereas rainforests are more light-limited