bluuebunny/crossref_metadata_2025_split huggingface dataset:
Kir3-Based Inward Rectifier Potassium Current
Authors: Cha Tae-Joon , Ehrlich Joachim R. , Chartier Denis , Qi Xiao-Yan , Xiao Ling , Nattel Stanley 
Published: April 2006

Background—We previously characterized a novel K+current (IKH) with properties of constitutively active acetylcholine-related current in dog atrium.IKHis sensitive to tertiapin-Q (IC50≈10 nmol/L), a highly selective Kir3 current blocker. This study assessed the role ofIKHin atrial tachycardia (AT)–remodeled canine left atrium (LA) with the use of tertiapin-Q as a probe.Methods and Results—Dogs were subjected to 7 to 13 days of AT (400 bpm). Coronary-perfused LA preparations were studied intact or subjected to cardiomyocyte isolation.IKHwas recorded with patch-clamp methods. AT pacing increased time-dependent hyperpolarization-activated current (IKH) at −110 mV from −1.8±0.3 (control) to −3.4±0.5 pA/pF (AT) and the 100-nmol/L tertiapin-sensitive component from −1.5±0.4 (control) to −3.3±0.6 pA/pF (AT). Prolonged atrial tachyarrhythmias could be induced with single extrastimuli in AT-remodeled, but not control, preparations, reflecting the atrial fibrillation–promoting effects of AT remodeling. In AT-remodeled preparations, tachyarrhythmia duration averaged 11.0±5.2 seconds, with a cycle length of 108±6 ms. Tertiapin-Q decreased tachyarrhythmia duration (to 0.6±0.1 second;P<0.001) and increased tachyarrhythmia cycle length (to 175±10 ms;P<0.001). Atrial action potential duration (APD) was increased 65±6% by tertiapin in AT-remodeled hearts versus 19±2% (P<0.001) in control. In 2 AT-remodeled preparations, tachyarrhythmia lasted uninterrupted for >20 minutes; tertiapin-Q slowed and then terminated arrhythmia in both. Tertiapin had no effect on left ventricular cardiomyocyte currents or APD.Conclusions—AT remodeling increasesIKH, and a highly selective Kir3 current antagonist, tertiapin-Q, increases APD and suppresses atrial tachyarrhythmias in AT-remodeled preparations without affecting ventricular electrophysiology. Constitutive acetylcholine-related K+current contributes to AT-remodeling effects in dogs and is a potentially interesting antiarrhythmic target.
How Environmental is African Traditional Religion?
Authors: Taringa Nisbert 
Published: April 2006

AbstractThis article examines some of the beliefs and practices underlying traditional African religion's attitudes to nature with reference to Shona religion of Zimbabwe. At the theoretical level, assuming a romantic view of Shona attitudes to nature, it is possible to conclude that Shona traditional religion is necessarily environmentally friendly. The strong beliefs in ancestral spirits (midzimu), pan-vitalism, kinship, taboo and totems have the potential to bear testimony to this. The aim of this article is to critically examine the extent of the claims that Shona traditional religion is environmentally friendly. It shows that Shona attitudes to nature are in fact discriminative and ambivalent. I argue that the ecological attitude of traditional African religion is more based on fear or respect of ancestral spirits than on respect for nature itself. As a result we need to re-examine Shona attitudes to nature if Shona traditional religion is to re-emerge as a stronger environmental force in the global village. After introductory remarks the article gives an overview background about the Shona focusing on their socio-political organization, world-view and religion. An examination of Shona attitudes to nature focusing on the land, animals, and plant life and water bodies follows. After this there is a reflection on the ethical consequences of Shona attitudes to nature. The last part considers the limits of the romantic view of Shona attitudes to nature.
GFDL's CM2 Global Coupled Climate Models. Part II: The Baseline Ocean Simulation
Authors: Gnanadesikan Anand , Dixon Keith W. , Griffies Stephen M. , Balaji V. , Barreiro Marcelo , Beesley J. Anthony , Cooke William F. , Delworth Thomas L. , Gerdes Rudiger , Harrison Matthew J. , Held Isaac M. , Hurlin William J. , Lee Hyun-Chul , Liang Zhi , Nong Giang , Pacanowski Ronald C. , Rosati Anthony , Russell Joellen , Samuels Bonita L. , Song Qian , Spelman Michael J. , Stouffer Ronald J. , Sweeney Colm O. , Vecchi Gabriel , Winton Michael , Wittenberg Andrew T. , Zeng Fanrong , Zhang Rong , Dunne John P. 
Published: April 2006

Abstract
The current generation of coupled climate models run at the Geophysical Fluid Dynamics Laboratory (GFDL) as part of the Climate Change Science Program contains ocean components that differ in almost every respect from those contained in previous generations of GFDL climate models. This paper summarizes the new physical features of the models and examines the simulations that they produce. Of the two new coupled climate model versions 2.1 (CM2.1) and 2.0 (CM2.0), the CM2.1 model represents a major improvement over CM2.0 in most of the major oceanic features examined, with strikingly lower drifts in hydrographic fields such as temperature and salinity, more realistic ventilation of the deep ocean, and currents that are closer to their observed values. Regional analysis of the differences between the models highlights the importance of wind stress in determining the circulation, particularly in the Southern Ocean. At present, major errors in both models are associated with Northern Hemisphere Mode Waters and outflows from overflows, particularly the Mediterranean Sea and Red Sea.
GFDL's CM2 Global Coupled Climate Models. Part III: Tropical Pacific Climate and ENSO
Authors: Wittenberg Andrew T. , Rosati Anthony , Lau Ngar-Cheung , Ploshay Jeffrey J. 
Published: April 2006

Abstract
Multicentury integrations from two global coupled ocean–atmosphere–land–ice models [Climate Model versions 2.0 (CM2.0) and 2.1 (CM2.1), developed at the Geophysical Fluid Dynamics Laboratory] are described in terms of their tropical Pacific climate and El Niño–Southern Oscillation (ENSO). The integrations are run without flux adjustments and provide generally realistic simulations of tropical Pacific climate. The observed annual-mean trade winds and precipitation, sea surface temperature, surface heat fluxes, surface currents, Equatorial Undercurrent, and subsurface thermal structure are well captured by the models. Some biases are evident, including a cold SST bias along the equator, a warm bias along the coast of South America, and a westward extension of the trade winds relative to observations. Along the equator, the models exhibit a robust, westward-propagating annual cycle of SST and zonal winds. During boreal spring, excessive rainfall south of the equator is linked to an unrealistic reversal of the simulated meridional winds in the east, and a stronger-than-observed semiannual signal is evident in the zonal winds and Equatorial Undercurrent.
Both CM2.0 and CM2.1 have a robust ENSO with multidecadal fluctuations in amplitude, an irregular period between 2 and 5 yr, and a distribution of SST anomalies that is skewed toward warm events as observed. The evolution of subsurface temperature and current anomalies is also quite realistic. However, the simulated SST anomalies are too strong, too weakly damped by surface heat fluxes, and not as clearly phase locked to the end of the calendar year as in observations. The simulated patterns of tropical Pacific SST, wind stress, and precipitation variability are displaced 20°–30° west of the observed patterns, as are the simulated ENSO teleconnections to wintertime 200-hPa heights over Canada and the northeastern Pacific Ocean. Despite this, the impacts of ENSO on summertime and wintertime precipitation outside the tropical Pacific appear to be well simulated. Impacts of the annual-mean biases on the simulated variability are discussed.
GFDL's CM2 Global Coupled Climate Models. Part IV: Idealized Climate Response
Authors: Stouffer R. J. , Broccoli A. J. , Delworth T. L. , Dixon K. W. , Gudgel R. , Held I. , Hemler R. , Knutson T. , Lee Hyun-Chul , Schwarzkopf M. D. , Soden B. , Spelman M. J. , Winton M. , Zeng Fanrong 
Published: April 2006

Abstract
The climate response to idealized changes in the atmospheric CO2 concentration by the new GFDL climate model (CM2) is documented. This new model is very different from earlier GFDL models in its parameterizations of subgrid-scale physical processes, numerical algorithms, and resolution. The model was constructed to be useful for both seasonal-to-interannual predictions and climate change research. Unlike previous versions of the global coupled GFDL climate models, CM2 does not use flux adjustments to maintain a stable control climate. Results from two model versions, Climate Model versions 2.0 (CM2.0) and 2.1 (CM2.1), are presented.
Two atmosphere–mixed layer ocean or slab models, Slab Model versions 2.0 (SM2.0) and 2.1 (SM2.1), are constructed corresponding to CM2.0 and CM2.1. Using the SM2 models to estimate the climate sensitivity, it is found that the equilibrium globally averaged surface air temperature increases 2.9 (SM2.0) and 3.4 K (SM2.1) for a doubling of the atmospheric CO2 concentration. When forced by a 1% per year CO2 increase, the surface air temperature difference around the time of CO2 doubling [transient climate response (TCR)] is about 1.6 K for both coupled model versions (CM2.0 and CM2.1). The simulated warming is near the median of the responses documented for the climate models used in the 2001 Intergovernmental Panel on Climate Change (IPCC) Working Group I Third Assessment Report (TAR).
The thermohaline circulation (THC) weakened in response to increasing atmospheric CO2. By the time of CO2 doubling, the weakening in CM2.1 is larger than that found in CM2.0: 7 and 4 Sv (1 Sv ≡ 106 m3 s−1), respectively. However, the THC in the control integration of CM2.1 is stronger than in CM2.0, so that the percentage change in the THC between the two versions is more similar. The average THC change for the models presented in the TAR is about 3 or 4 Sv; however, the range across the model results is very large, varying from a slight increase (+2 Sv) to a large decrease (−10 Sv).
Assessing Global Vegetation–Climate Feedbacks from Observations*
Authors: Liu Zhengyu , Notaro M. , Kutzbach J. , Liu Naizhuang 
Published: April 2006

Abstract
The feedback between global vegetation greenness and surface air temperature and precipitation is assessed using remote sensing observations of monthly fraction of photosynthetically active radiation (FPAR) for 1982 to 2000 with a 2.5° grid resolution. Lead/lag correlations are used to infer vegetation–climate interactions. Furthermore, a statistical method is used to quantify the efficiency of vegetation feedback on climate in the observations. This feedback analysis provides a first quantitative assessment of global vegetation feedback on climate. In northern mid- and high latitudes, vegetation variability is found to be driven predominantly by temperature; in the meantime, vegetation also exerts a strong positive feedback on temperature with the feedback accounting for over 10%–25% of the total monthly temperature variance. The strongest positive feedback occurs in the boreal regions of southern Canada/northern United States, northern Europe, and southern Siberia, where the feedback efficiency exceeds 1°C (0.1 FPAR)−1. Over most of the Tropics and subtropics (outside the equatorial rain belt), vegetation is driven primarily by precipitation. However, little vegetation feedback is found on local precipitation when averaged year-round, with the feedback explained variance usually accounting for less than 5% of the total precipitation variance. Nevertheless, in a few isolated small regions such as Northeast Brazil, East Africa, East Asia, and northern Australia, there appears to be some positive vegetation feedback on local precipitation, with the feedback efficiency over 1 cm month−1 (0.1 FPAR)−1. Further studies suggest a significant seasonal variation of the vegetation feedback in some regions. A preliminary analysis also seems to suggest an enhanced intensity of the vegetation feedback, especially on precipitation, at longer time scales and over a larger grid box area. Limitations and implications of the assessment of vegetation feedback are also discussed. The assessed vegetation feedback is shown to be valuable for the evaluation of vegetation–climate feedback in coupled climate–vegetation models.
Attributes of Several Methods for Detecting Discontinuities in Mean Temperature Series
Authors: DeGaetano Arthur T. 
Published: April 2006

Abstract
Simulated annual temperature series are used to compare seven homogenization procedures. The two that employ likelihood ratio tests routinely outperform other methods in their ability to identify modest (0.33°C; 0.6 standard deviation anomaly) shifts in the mean. The percentage of imposed shifts that are detected by these methods is similar to that based on tests that rely on a priori metadata information concerning the position of potential shifts. These methods, along with a two-phase regression approach, are also best at identifying and placing multiple shifts within a single time series. Although the regression procedure is better able to detect multiple breaks that are separated by relatively short time intervals, in its published form it suffers from a higher-than-expected Type I error rate. This was also found to be a problem with a metadata-based procedure currently in operational use. The likelihood tests are strongly influenced by the presence of trends in the difference series and short (&lt;20 yr) series length.
The ability of a given procedure to detect a discontinuity is predominately influenced by the magnitude of the discontinuity relative to the standard deviation of the data series being evaluated. Data series length, correlation between the test series and its associated reference series, and test series autocorrelation also influence test performance. These features were not considered in previous homogenization method comparisons.
Discontinuities with magnitudes less than 0.6 times the standard deviation of the time series represent the lower limit for homogenization. Based on the most effective homogenization techniques, 10% of the 1.25 standard deviation discontinuities are likely to remain in climatic data series, unless reference station correlations are exceptional or quality station metadata are available.
Measurement Requirements for Climate Monitoring of Upper-Air Temperature Derived from Reanalysis Data
Authors: Seidel Dian J. , Free Melissa 
Published: April 2006

Abstract
Using a reanalysis of the climate of the past half century as a model of temperature variations over the next half century, tests of various data collection protocols are made to develop recommendations for observing system requirements for monitoring upper-air temperature. The analysis focuses on accurately estimating monthly climatic data (specifically, monthly average temperature and its standard deviation) and multidecadal trends in monthly temperatures at specified locations, from the surface to 30 hPa. It does not address upper-air network size or station location issues.
The effects of reducing the precision of temperature data, incomplete sampling of the diurnal cycle, incomplete sampling of the days of the month, imperfect long-term stability of the observations, and changes in observation schedule are assessed. To ensure accurate monthly climate statistics, observations with at least 0.5-K precision, made at least twice daily, at least once every two or three days are sufficient. Using these same criteria, and maintaining long-term measurement stability to within 0.25 (0.1) K, for periods of 20 to 50 yr, errors in trend estimates can be avoided in at least 90% (95%) of cases. In practical terms, this requires no more than one intervention (e.g., instrument change) over the period of record, and its effect must be to change the measurement bias by no more than 0.25 (0.1) K. The effect of the first intervention dominates the effects of subsequent, uncorrelated interventions. Changes in observation schedule also affect trend estimates. Reducing the number of observations per day, or changing the timing of a single observation per day, has a greater potential to produce errors in trends than reducing the number of days per month on which observations are made.
These findings depend on the validity of using reanalysis data to approximate the statistical nature of future climate variations, and on the statistical tests employed. However, the results are based on conservative assumptions, so that adopting observing system requirements based on this analysis should result in a data archive that will meet climate monitoring needs over the next 50 yr.
Role of Land Surface Processes in South American Monsoon Development
Authors: Xue Yongkang , de Sales F. , Li W-P. , Mechoso C. R. , Nobre C. A. , Juang H-M. 
Published: April 2006

Abstract
This study explores the role of vegetation biophysical processes (VBPs) in the structure and evolution of the South American monsoon system (SAMS) with an emphasis on the precipitation field. The approach is based on comparing ensemble simulations by the National Centers for Environmental Prediction general circulation model (GCM) in which the land surface parameterization in one ensemble includes an explicit representation of vegetation processes in the calculation of surface fluxes while the other does not [GCM/Simplified Simple Biosphere Model (SSiB) and GCM/Soil, respectively], but with similar monthly mean surface albedo and initial soil moisture. The ensembles consist of five pairs of 1-yr integrations differing in the initial conditions for the atmosphere. The results show that, during the austral summer, consideration of explicit vegetation processes does not alter the monthly mean precipitation at the planetary scale. However, at continental scales, GCM/SSiB produces a more successful simulation of SAMS than GCM/Soil. The improvement is particularly clear in reference to the seasonal southward displacement of precipitation during the onset of the SAMS and its northward merging with the intertropical convergence zone during the monsoon mature stage, as well as better monthly mean austral summer precipitation over the South American continent.
The changes in surface water and energy balances and circulation in October (monsoon onset) and December (the start of the monsoon mature stage) were analyzed for a better understanding of the results and mechanisms involved. It was found that the major difference between the simulations is in the partitioning of latent heat and sensible heat fluxes (i.e., different Bowen ratio), which produced different latitudinal and longitudinal thermal gradients at the surface. A stronger sensible heat flux gradient between continent and ocean in the GCM/SSiB simulation helped generate an enhanced ventilation effect, which lowered moist static energy (MSE) over the northeast coast of South America leading to stronger counterclockwise turning of the low-level wind from the Atlantic Ocean toward the continent during the premonsoon and early monsoon stages, modifying moisture flux convergence (MFC). It was further identified that the seasonality of savanna and shrublands to the south and east of the Amazon rain forest contributed to the variability of heating gradients and influenced the SAMS onset and its northward merge with the ITCZ at the early monsoon mature stage. The comparison of the differences between precipitation, evaporation, advection of MSE, and MFC based on simulations using two different land parameterizations suggested that the VBP modulated the surface water budget, but its impact on precipitation was determined by the changes in circulation via changes in heat gradient and MSE.
Mandate for Creation of a National Peripheral Arterial Disease Public Awareness Program: An Opportunity to Improve Cardiovascular Health
Authors: Hirsch Alan T. , Gloviczki Peter , Drooz Alain , Lovell Marge , Creager Mark A. ,   The Board of Directors of the Vascular Disease Foundation
Published: April 2006

Background: There has been increasing recognition of the detrimental effect of peripheral arterial disease (PAD) on the health of Americans, and yet there is no common national program of public PAD education designed to diminish this effect.Format: To heighten awareness of this problem, a 2-day PAD Public Education Strategy Meeting was recently attended by representatives of 17 professional societies and public health associations whose missions support the prevention, diagnosis, treatment, and rehabilitation of vascular diseases. This Public Education Strategy Meeting was intended to provide the rationale and structure to create a national PAD public awareness campaign to diminish the health effect of PAD and to improve cardiovascular outcomes in the United States. This document (1) provides the rationale for creation of a national PAD public education program; (2) reviews the development and success of national hypertension, hypercholesterolemia, and Women’s Heart Health public education programs as models of educational efficacy; (3) elucidates how the work of many vascular professionals has led to a national consensus for creation of a national PAD public educational program; (4) provides an overview of the National Heart, Lung, and Blood Institute PAD education meeting; and (5) outlines the “next steps” required to accomplish these goals.Outcome: This meeting achieved consensus that we share responsibility for developing accurate, unified messages to promote PAD awareness and improved care. Participants agreed
Language Learning Styles and Learning Strategies of Tertiary-Level English Learners in China
Authors: Jie Li , Xiaoqing Qin 
Published: April 2006

This study focuses on the relationship between learning styles and language learning strategies in the EFL context in China. The study presents two kinds of data: quantitative and qualitative. In the quantitative study, the subjects consisted of 187 second-year undergraduates. Two self-reported inventories, the Chinese version of MBTI-G and a questionnaire on the use of learning strategies adapted from O’Malley and Chamot’s classification system, were used to examine the students’ learning styles and learning strategies respectively. Structured interviews have been performed among the six high and low achievers in the qualitative aspect of the study.The analyses show that learning styles have a significant influence on learners’ learning strategy choices. There is evidence that the Judging scale correlates positively with seven sets of learning strategies. Thus it turns out to be the most influential learning style variable affecting learners’ learning strategy choices. Compared with low achievers, high achievers are more capable of exercising strategies that are associated with their non-preferred styles.Based on the available research results, it is proposed that learning styles may influence learners’ language learning outcomes through their relationship with learning strategies. The pedagogical implications of these findings are discussed, as are suggestions for future research.