bluuebunny/crossref_metadata_2025 huggingface dataset:
Chemokines in Atherosclerosis
Authors: Zernecke Alma , Shagdarsuren Erdenechimeg , Weber Christian
Published: June 2008

The fundamental importance of chemokines for atherogenesis, progression, and destabilization of atherosclerotic plaques is now widely appreciated, but the degree of complexity, specificity, and cooperativity harnessed by these signal molecules to govern atherogenic cell recruitment and homeostasis is still being refined. Since the role of chemokines in atherosclerotic vascular disease has been reviewed in this journal, significant progress has been accomplished in defining the regulation of chemokine expression and function in atherosclerosis. In this update, we will highlight these recent developments, in particular the identification of components regulating the transcriptional machinery of the proatherogenic chemokine CCL5, distinct roles of its receptors CCR1 and CCR5 in plaque formation and immunobalance, and differential site- and stage-specific effects of T cell–activating chemokines and their receptors, eg, CXCL10 and CXCR3. The contribution of the transmembrane chemokines CX
3
CL1 and CXCL16 with their respective receptors CX
3
CR1 and CXCR6 in the recruitment of T cell and monocyte subsets and shear-mediated plaque modulation will be discussed. Finally, the role of CXCR2 and CXCR4, their respective ligands CXCL1 and CXCL12, and the noncanonical dual agonist MIF in atheroprogression will be dissected. The considerable leap in insight over recent years leads us to anticipate further advances in comprehending the role of chemokines in atherosclerosis, allowing targeted interventions for its prevention and therapy.
Extended-Release Niacin Alters the Metabolism of Plasma Apolipoprotein (Apo) A-I and ApoB-Containing Lipoproteins
Authors: Lamon-Fava Stefania , Diffenderfer Margaret R. , Barrett P. Hugh R. , Buchsbaum Aaron , Nyaku Mawuli , Horvath Katalin V. , Asztalos Bela F. , Otokozawa Seiko , Ai Masumi , Matthan Nirupa R. , Lichtenstein Alice H. , Dolnikowski Gregory G. , Schaefer Ernst J.
Published: June 2008

Objectives—

Extended-release niacin effectively lowers plasma TG levels and raises plasma high-density lipoprotein (HDL) cholesterol levels, but the mechanisms responsible for these effects are unclear.

Methods and Results—

We examined the effects of extended-release niacin (2 g/d) and extended-release niacin (2 g/d) plus lovastatin (40 mg/d), relative to placebo, on the kinetics of apolipoprotein (apo) A-I and apoA-II in HDL, apoB-100 in TG-rich lipoproteins (TRL), intermediate-density lipoproteins (IDL) and low-density lipoproteins (LDL), and apoB-48 in TRL in 5 men with combined hyperlipidemia. Niacin significantly increased HDL cholesterol and apoA-I concentrations, associated with a significant increase in apoA-I production rate (PR) and no change in fractional catabolic rate (FCR). Plasma TRL apoB-100 levels were significantly lowered by niacin, accompanied by a trend toward an increase in FCR and no change in PR. Niacin treatment significantly increased TRL apoB-48 FCR but had no effect on apoB-48 PR. No effects of niacin on concentrations or kinetic parameters of IDL and LDL apoB-100 and HDL apoA-II were noted. The addition of lovastatin to niacin promoted a lowering in LDL apoB-100 attributable to increased LDL apoB-100 FCR.

Conclusion—

Niacin treatment was associated with significant increases in HDL apoA-I concentrations and production, as well as enhanced clearance of TRL apoB-100 and apoB-48.
Adipose Macrophage Infiltration Is Associated With Insulin Resistance and Vascular Endothelial Dysfunction in Obese Subjects
Authors: Apovian Caroline M. , Bigornia Sherman , Mott Melanie , Meyers Melissa R. , Ulloor Jagadish , Gagua Manana , McDonnell Marie , Hess Donald , Joseph Lija , Gokce Noyan
Published: June 2008

Objective—

Experimental studies suggest that adipose inflammation is etiologically linked to obesity-induced systemic disease. Our goal was to characterize the state of inflammation in human fat in relation to vascular function and metabolic parameters in obese individuals.

Methods and Results—

We collected subcutaneous abdominal fat in 77 obese subjects (BMI ≥30 kg/m
2
) and quantified adipose macrophage population using targeted immunohistochemistry. Brachial artery vasodilator function was examined using high-resolution vascular ultrasound. In 50 subjects, an inflamed adipose phenotype characterized by tissue macrophage accumulation in crown-like structures was associated with systemic hyperinsulinemia and insulin resistance (HOMA-IR 5.5±4.5 versus 2.6±1.9,
P
=0.002) and impaired endothelium-dependent flow-mediated vasodilation (8.5±4.4% versus 10.8±3.8%,
P
<0.05), as compared to subjects with quiescent noninflamed adipose architecture (n=27). Macrophage retention in fat was linked to upregulated tissue CD68 and tumor necrosis factor (TNF)-α mRNA expression in addition to increased plasma hs-CRP.

Conclusions—

In a cohort of obese subjects, we demonstrate that proinflammatory changes in adipose tissue are associated with systemic arterial dysfunction and insulin resistance. These findings suggest that adipose inflammation may be linked to vascular injury and increased cardiovascular risk in obese subjects.
Atorvastatin and Fenofibrate Have Comparable Effects on VLDL-Apolipoprotein C-III Kinetics in Men With the Metabolic Syndrome
Authors: Chan Dick C. , Watts Gerald F. , Ooi Esther M.M. , Ji Juying , Johnson Anthony G. , Barrett P. Hugh R.
Published: June 2008

Objectives—

The metabolic syndrome (MetS) is characterized by insulin resistance and dyslipidemia that may accelerate atherosclerosis. Disturbed apolipoprotein (apo) C-III metabolism may account for dyslipidemia in these subjects. Atorvastatin and fenofibrate decrease plasma apoC-III, but the underlying mechanisms are not fully understood.

Methods and Results—

The effects of atorvastatin (40 mg/d) and fenofibrate (200 mg/d) on the kinetics of very-low density lipoprotein (VLDL)-apoC-III were investigated in a crossover trial of 11 MetS men. VLDL-apoC-III kinetics were studied, after intravenous d
3
-leucine administration using gas chromatography-mass spectrometry and compartmental modeling. Compared with placebo, both atorvastatin and fenofibrate significantly decreased (
P
<0.001) plasma concentrations of triglyceride, apoB, apoB-48, and total apoC-III. Atorvastatin, not fenofibrate, significantly decreased plasma apoA-V concentrations (
P
<0.05). Both agents significantly increased the fractional catabolic rate (+32% and +30%, respectively) and reduced the production rate of VLDL-apoC-III (−20% and −24%, respectively), accounting for a significant reduction in VLDL-apoC-III concentrations (−41% and −39%, respectively). Total plasma apoC-III production rates were not significantly altered by the 2 agents. Neither treatment altered insulin resistance and body weight.

Conclusions—

Both atorvastatin and fenofibrate have dual regulatory effects on VLDL-apoC-III kinetics in MetS; reduced production and increased fractional catabolism of VLDL-apoC-III may explain the triglyceride-lowering effect of these agents.
Genetic Factors for Ischemic and Hemorrhagic Stroke in Japanese Individuals
Authors: Yamada Yoshiji , Metoki Norifumi , Yoshida Hidemi , Satoh Kei , Kato Kimihiko , Hibino Takeshi , Yokoi Kiyoshi , Watanabe Sachiro , Ichihara Sahoko , Aoyagi Yukitoshi , Yasunaga Akitomo , Park Hyuntae , Tanaka Masashi , Nozawa Yoshinori
Published: June 2008

Background and Purpose—

Although genetic epidemiologic studies have implicated several genetic variants as risk factors for ischemic or hemorrhagic stroke, the genetic determinants of these conditions remain largely unknown. We performed an association study to identify gene polymorphisms that confer susceptibility to atherothrombotic cerebral infarction, intracerebral hemorrhage, or subarachnoid hemorrhage.

Methods—

The study population comprised 3432 unrelated Japanese individuals: 1362 stroke patients (822 with atherothrombotic cerebral infarction, 333 with intracerebral hemorrhage, and 207 with subarachnoid hemorrhage) and 2070 controls. The genotypes for 50 polymorphisms of 38 candidate genes were determined by a method that combines the polymerase chain reaction and sequence-specific oligonucleotide probes with suspension array technology.

Results—

An initial χ
2
test (false discovery rate <0.05) and subsequent multivariable logistic-regression analysis with adjustment for conventional risk factors (
P
<0.05) revealed that the −14C→T polymorphism (rs1800977) of
ABCA1
, the A→C (rs3027898) and C→T (Ser532Leu, rs1059703) polymorphisms of
IRAK1
, and the G→C (Cys2229Ser) polymorphism (rs619203) of
ROS1
were significantly associated with atherothrombotic cerebral infarction; that the −428G→A polymorphism (rs710968) of
LIMK1
was significantly associated with intracerebral hemorrhage; and that the 13989A→G (Ile118Val) polymorphism (NC_000007.12) of
CYP3A4
was significantly associated with subarachnoid hemorrhage.

Conclusions—

Genotypes for
ABCA1
,
IRAK1
, and
ROS1
may prove useful for assessment of the genetic risk for atherothrombotic cerebral infarction, whereas those for
LIMK1
and
CYP3A4
may be similarly beneficial in assessment of the genetic risk for intracerebral hemorrhage and subarachnoid hemorrhage, respectively. Validation of these findings will require additional studies with independent subject panels.
The Atmospheric Water Balance over the Semiarid Murray–Darling River Basin
Authors: Draper Clara , Mills Graham
Published: June 2008

The atmospheric water balance over the semiarid Murray–Darling River basin in southeast Australia is analyzed based on a consecutive series of 3- to 24-h NWP forecasts from the Australian Bureau of Meteorology’s Limited Area Prediction System (LAPS). Investigation of the LAPS atmospheric water balance, including comparison of the forecast precipitation to analyzed rain gauge observations, indicates that the LAPS forecasts capture the general qualitative features of the water balance. The key features of the atmospheric water balance over the Murray–Darling Basin are small atmospheric moisture flux divergence (at daily to annual time scales) and extended periods during which the atmospheric water balance terms are largely inactive, with the exception of evaporation, which is consistent and very large in summer. These features present unique challenges for NWP modeling. For example, the small moisture fluxes in the basin can easily be obscured by the systematic errors inherent in all NWP models. For the LAPS model forecasts, there is an unrealistically large evaporation excess over precipitation (associated with a positive bias in evaporation) and unexpected behavior in the moisture flux divergence. Two global reanalysis products (the NCEP Reanalysis I and the 40-yr ECMWF Re-Analysis) also both describe (physically unrealistic) long-term negative surface water budgets over the Murray–Darling Basin, suggesting that the surface water budget cannot be sensibly diagnosed based on output from current NWP models. Despite this shortcoming, numerical models are in general the most appropriate tool for examining the atmospheric water balance over the Murray–Darling Basin, as the atmospheric sounding network in Australia has extremely low coverage.
An Assessment of the Biases of Satellite Rainfall Estimates over the Tibetan Plateau and Correction Methods Based on Topographic Analysis
Authors: Yin Zhi-Yong , Zhang Xueqin , Liu Xiaodong , Colella Mike , Chen Xiaoling
Published: June 2008

The hydrological processes over the Tibetan Plateau have significant implications on regional macroscale atmospheric circulation patterns and the Asian monsoon system. Because of its remote setting and lack of ground observations, it is difficult to study the spatial and temporal patterns of precipitation over the plateau, and satellite remote sensing technology can be used to fill in the gaps where station data are not available. In this study the authors examine monthly 1° × 1° rainfall estimates obtained from the Special Sensor Microwave Imager (SSM/I) [National Environmental Satellite, Data, and Information Service (NESDIS) algorithm] and Tropical Rainfall Measuring Mission (TRMM) 3B42 version 5 (V5) products for the months of April–October 1998–2002 over the Tibetan Plateau. By comparing the satellite estimates with ground observations at 94 weather stations in the study region, the authors derived regression models that produced significant improvements to satellite estimates based on various levels of correction efforts, using geographic location and topographic variables extracted from digital elevation models using geographic information systems (GIS) technology. The explained variance in observed precipitation was improved from 34% to 38% by SSM/I and TRMM 3B42 V5 products alone to over 70% when location and topographic variables were added. These topographic variables reflect micro- to mesoscale surface roughness, height of topographic features or relief, slopes facing toward or away from the moisture pathways, and relative locations or directions to prominent topographic features such as mountain peaks and ridgelines.
Simulation of Evapotranspiration and Its Response to Plant Water and CO2 Transfer Dynamics
Authors: Wang Shusen
Published: June 2008

Evapotranspiration (ET) is controlled by atmospheric demand, plant and soil hydraulic constraints, and the plant physiological activities that determine canopy resistance. This paper introduces a new ET scheme developed for the Ecological Assimilation of Land and Climate Observations (EALCO) model that integrates these controls into one dynamic system. This scheme is based on solving the governing equation system that represents the coupled canopy energy–water–CO2 transfer dynamics, where the canopy temperature Tc, plant water potential ψc, and leaf intercellular CO2 concentrations Ci are simultaneously obtained and used in ET calculations. Modeled ET was compared with eddy correlation flux measurement at a boreal aspen forest. Results showed that the correlation coefficient (R) between modeled and measured daily ET was greater than 0.96. The average absolute error was approximately 0.3 mm day−1. Modeled ET was generally higher than measured ET by 10%. This is consistent with the energy balance closure analyses from observations that showed that turbulent energy flux was frequently less than 90% of the total available energy. The effects of the plant CO2 and water transfer dynamics on ET simulations were investigated by running the model in two additional settings. These were 1) static Ci—where the ratio of Ci to atmospheric CO2 concentration was set to a constant value, and 2) static ψc—where the ψc was linearly related to soil water potential. The dynamic CO2 transfer scheme and the static Ci scheme produced relatively small differences in ET that mainly occurred at a subdaily time scale. Differences in ET produced using the dynamic water transfer scheme and the static ψc scheme depended on ecosystem water conditions and were more significant when the plant was under water stress. Ignoring the dynamic water transfer process in the model decreased the correlation coefficient between modeled and measured ET more significantly in drier years. This implies that the dynamic water transfer scheme is of more importance for ET estimates in arid or semiarid ecosystems.
Raindrop Size Distributions and Rain Characteristics in California Coastal Rainfall for Periods with and without a Radar Bright Band
Authors: Martner Brooks E. , Yuter Sandra E. , White Allen B. , Matrosov Sergey Y. , Kingsmill David E. , Ralph F. Martin
Published: June 2008

Recent studies using vertically pointing S-band profiling radars showed that coastal winter storms in California and Oregon frequently do not display a melting-layer radar bright band and inferred that these nonbrightband (NBB) periods are characterized by raindrop size spectra that differ markedly from those of brightband (BB) periods. Two coastal sites in northern California were revisited in the winter of 2003/04 in this study, which extends the earlier work by augmenting the profiling radar observations with collocated raindrop disdrometers to measure drop size distributions (DSD) at the surface. The disdrometer observations are analyzed for more than 320 h of nonconvective rainfall. The new measurements confirm the earlier inferences that NBB rainfall periods are characterized by greater concentrations of small drops and smaller concentrations of large drops than BB periods. Compared with their BB counterparts, NBB periods had mean values that were 40% smaller for mean-volume diameter, 32% smaller for rain intensity, 87% larger for total drop concentration, and 81% larger (steeper) for slope of the exponential DSDs. The differences are statistically significant. Liquid water contents differ very little, however, for the two rain types. Disdrometer-based relations between radar reflectivity (Z) and rainfall intensity (R) at the site in the Coast Range Mountains were Z = 168R1.58 for BB periods and Z = 44R1.91 for NBB. The much lower coefficient, which is characteristic of NBB rainfall, is poorly represented by the Z–R equations most commonly applied to data from the operational network of Weather Surveillance Radar-1988 Doppler (WSR-88D) units, which underestimate rain accumulations by a factor of 2 or more when applied to nonconvective NBB situations. Based on the observed DSDs, it is also concluded that polarimetric scanning radars may have some limited ability to distinguish between regions of BB and NBB rainfall using differential reflectivity. However, differential-phase estimations of rain intensity are not useful for NBB rain, because the drops are too small and nearly spherical. On average, the profiler-measured echo tops were 3.2 km lower in NBB periods than during BB periods, and they extended only about 1 km above the 0°C altitude. The findings are consistent with the concept that precipitation processes during BB periods are dominated by ice processes in deep cloud layers associated with synoptic-scale forcing, whereas the more restrained growth of hydrometeors in NBB periods is primarily the result of orographically forced condensation and coalescence processes in much shallower clouds.
Investigating Error Metrics for Satellite Rainfall Data at Hydrologically Relevant Scales
Authors: Hossain Faisal , Huffman George J.
Published: June 2008

This paper addresses the following open question: What set of error metrics for satellite rainfall data can advance the hydrologic application of new-generation, high-resolution rainfall products over land? The authors’ primary aim is to initiate a framework for building metrics that are mutually interpretable by hydrologists (users) and algorithm developers (data producers) and to provide more insightful information on the quality of the satellite estimates. In addition, hydrologists can use the framework to develop a space–time error model for simulating stochastic realizations of satellite estimates for quantification of the implication on hydrologic simulation uncertainty. First, the authors conceptualize the error metrics in three general dimensions: 1) spatial (how does the error vary in space?); 2) retrieval (how “off” is each rainfall estimate from the true value over rainy areas?); and 3) temporal (how does the error vary in time?). They suggest formulations for error metrics specific to each dimension, in addition to ones that are already widely used by the community. They then investigate the behavior of these metrics as a function of spatial scale ranging from 0.04° to 1.0° for the Precipitation Estimation from Remotely Sensed Information Using Artificial Neural Networks (PERSIANN) geostationary infrared-based algorithm. It is observed that moving to finer space–time scales for satellite rainfall estimation requires explicitly probabilistic measures that are mathematically amenable to space–time stochastic simulation of satellite rainfall data. The probability of detection of rain as a function of ground validation rainfall magnitude is found to be most sensitive to scale followed by the correlation length for detection of rain. Conventional metrics such as the correlation coefficient, frequency bias, false alarm ratio, and equitable threat score are found to be modestly sensitive to scales smaller than 0.24° latitude/longitude. Error metrics that account for an algorithm’s ability to capture rainfall intermittency as a function of space appear useful in identifying the useful spatial scales of application for the hydrologist. It is shown that metrics evolving from the proposed conceptual framework can identify seasonal and regional differences in reliability of four global satellite rainfall products over the United States more clearly than conventional metrics. The proposed framework for building such error metrics can lay a foundation for better interaction between the data-producing community and hydrologists in shaping the new generation of satellite-based, high-resolution rainfall products, including those being developed for the planned Global Precipitation Measurement (GPM) mission.
The Dry-Entropy Budget of a Moist Atmosphere
Authors: Romps David M.
Published: June 2008

The entropy budget has been a popular starting point for theories of the work, or dissipation, performed by moist atmospheres. For a dry atmosphere, the entropy budget provides a theory for the dissipation in terms of the imposed diabatic heat sources. For a moist atmosphere, the difficulties in quantifying irreversible moist processes or the value of the condensation temperature have so far frustrated efforts to construct a theory of dissipation. With this complication in mind, one of the goals here is to investigate the predictive power of the budget of dry entropy (i.e., the heat capacity times the logarithm of potential temperature).

Toward this end, the dry-entropy budget is derived for an atmosphere with realistic heat capacities and a solid-water phase, features that were absent from some previous studies of atmospheric entropy. It is shown that the dry-entropy budget may be interpreted as the sum of sources and sinks from six processes, which are, in order of decreasing magnitude, radiative cooling, condensation heating, sensible heating at the surface, wind-generated frictional dissipation, lifting of water, and transport of heat from the melting line to the upper troposphere. This picture leads to an alternative explanation for the low efficiency of the moist atmospheric engine.

Numerical simulations are presented from a new cloud-resolving model, Das Atmosphärische Modell, which was designed to conserve energy and close the dry-entropy budget. Simulations with and without subgrid diffusion of heat and water are compared to investigate the impact of subgrid parameterizations on the terms in the dry-entropy budget. The numerical results suggest a particularly simple parameterization of wind-generated dissipation that appears to be valid for changes in sea surface temperature and mean wind. The dry-entropy budget also points to various changes in forcings and parameterizations that could be expected to increase or decrease the wind-generated dissipation.
Causes of Interannual–Decadal Variability in the Meridional Overturning Circulation of the Midlatitude North Atlantic Ocean
Authors: Biastoch Arne , Böning Claus W. , Getzlaff Julia , Molines Jean-Marc , Madec Gurvan
Published: June 2008

The causes and characteristics of interannual–decadal variability of the meridional overturning circulation (MOC) in the North Atlantic are investigated with a suite of basin-scale ocean models [the Family of Linked Atlantic Model Experiments (FLAME)] and global ocean–ice models (ORCA), varying in resolution from medium to eddy resolving (½°–1/12°), using various forcing configurations built on bulk formulations invoking atmospheric reanalysis products. Comparison of the model hindcasts indicates similar MOC variability characteristics on time scales up to a decade; both model architectures also simulate an upward trend in MOC strength between the early 1970s and mid-1990s. The causes of the MOC changes are examined by perturbation experiments aimed selectively at the response to individual forcing components. The solutions emphasize an inherently linear character of the midlatitude MOC variability by demonstrating that the anomalies of a (non–eddy resolving) hindcast simulation can be understood as a superposition of decadal and longer-term signals originating from thermohaline forcing variability, and a higher-frequency wind-driven variability. The thermohaline MOC signal is linked to the variability in subarctic deep-water formation, and rapidly progressing to the tropical Atlantic. However, throughout the subtropical and midlatitude North Atlantic, this signal is effectively masked by stronger MOC variability related to wind forcing and, especially north of 30°–35°N, by internally induced (eddy) fluctuations.
Probing Regional Orographic Controls of Precipitation and Cloudiness in the Central Andes Using Satellite Data
Authors: Giovannettone Jason P. , Barros Ana P.
Published: June 2008

Data obtained from NOAA’s Geostationary Operational Environmental Satellite (GOES) and NASA’s Tropical Rainfall Measuring Mission (TRMM) satellites were used to investigate the relationships between topography, large-scale circulation, and the climatology of precipitation and cloudiness in the Andes—specifically over Peru and the Altiplano Plateau—at diurnal, seasonal, and interannual time scales. The spatial variability of cloudiness was assessed through empirical orthogonal function (EOF) analysis of GOES brightness temperatures. Results indicate that landform is the principal agent of the space–time variability of moist atmospheric processes in the Andes, with the first mode explaining up to 70% of all observed variability. These results substantiate the differences between “continental” (Andes and Himalayas) and “maritime” (Western Cordillera) orographic precipitation regimes, reflecting the degree to which upwind landmasses modulate moisture transport toward and across mountain barriers. GOES brightness temperatures show that afternoon convective activity during the rainy season is more intense on wet hydrometeorological years such as 2001, whereas the space–time structure of nighttime cloudiness at the foothills and outlets of deep interior valleys does not change during the monsoon and from one year to another independently of large-scale conditions. This suggests that daytime cloud formation and precipitation is strongly dependent on large-scale moisture transport. Interactions between mesoscale and ridge–valley circulations, which are locked to the topography, determine the space–time organization of clouds and precipitation at nighttime. This leads to strong clustering of precipitation features associated with enhanced convection at high elevations along the ridges and near the headwaters of the major river systems in the TRMM data.
The Conversion of Total Column Ozone Data to Numerical Weather Prediction Model Initializing Fields, with Simulations of the 24–25 January 2000 East Coast Snowstorm
Authors: Durnford Dorothy , Gyakum John , Atallah Eyad
Published: June 2008

Satellites are uniquely capable of providing uniform data coverage globally. Motivated by such capability, this study builds on a previously described methodology that generates numerical weather prediction (NWP) model initial conditions (ICs) from satellite total column ozone (TCO) data. The methodology is based on three principal steps: 1) conversion of TCO to mean potential vorticity (MPV) via linear regression, 2) conversion of two-dimensional MPV to three-dimensional potential vorticity (PV) via vertical mapping onto average PV profiles, and 3) inversion of the three-dimensional PV field to obtain model-initializing height, temperature, and wind fields in the mid- and upper troposphere. The overall accuracy of the process has been significantly increased through a substantial reworking of the details of this previous version. For instance, in recognition of the fact that TCO ridges tend to be less reliable than troughs, the authors vertically map an MPV field that is a synthesis of ozone-derived MPV troughs and analysis MPV ridges. The vertical mapping procedure itself produces a more physical three-dimensional PV field by eliminating unrealistically strong features at upper levels.

It is found that the ozone-influenced upper-level initializing fields improve the quantitative precipitation forecast (QPF) of the 24–25 January 2000 East Coast snowstorm for two of the three (re)analyses. Furthermore, the best QPF involves ozone-influenced upper-level initializing fields. Its high threat scores reflect a superior placement, amplitude, and structure. This best QPF is apparently superior to a forecast of the same case where TCO data were assimilated using four-dimensional variational data assimilation.
The Sex Worker and Her Pleasure
Authors: Kontula Anna
Published: June 2008

The stereotypical view of prostitution is based on the idea that sex work destroys the woman's capability for sexual pleasure and alienates her from her sexuality. The author argues that the idea of the destructive capacity of sex work is not universally obvious. Sex workers interviewed seem to derive sexual pleasure in both commercial and private relationships. Professional sex work can be perceived as a distancing from the prostitute's own enjoyment but it can also be a channel to a more emancipated and pleasurable sex life.
Development of Needle-punched Nonwoven Fabrics from Flax Fibers for Air Filtration Applications
Authors: Anandjiwala Rajesh D. , Boguslavsky Lydia
Published: June 2008

This paper reports an exploratory study on the production and measurement of the air permeability, mechanical properties, pore size distribution and filtration efficiency of different nonwoven fabrics produced by systematically changing the machine variables to influence the physical parameters of the fabrics. Only flax fiber waste was utilized for this trial, so that the possibility of value addition to a cheap source of raw material could be explored. The changes in air permeability were interpreted in terms of fabric density profile and pore size distribution. The tensile strength, fiber orientation distribution and bond strength between the layers of multi-layered fabrics were investigated. The filtration parameters, such as filtration efficiency, dust holding capacity and pressure drop, were evaluated. Furthermore, the effect of calendering on pore size and filtration properties was evaluated to explore the possibility of fine-tuning the performance of filters. The results in this study showed an overall improvement in all filtration characteristics due to the calendering operation.
The Nature of Metropolitan Governance in Urban America
Authors: Wood Curtis
Published: June 2008

The evidence in this study demonstrates that the dominant pattern of metropolitan governance in the Kansas City metro area across 46 cities and 28 public services is one of intergovernmental cooperation, punctuated by conflict. Contrary to what would be predicted by theories of cooperation, the scope of cooperation is negatively related to the number and percent of joint intergovernmental service arrangements and that the scope of cooperation increases when a municipality transfers a service to another public entity or a municipality specializes in a regional service.
The Establishment and Promotion of the First Youth Quitline in Hong Kong Challenges and Opportunities
Authors: Chan Sophia S. C. , Wong David C. N. , Fong Daniel Y. T. , Leung Angela Y. M. , Lam Debbie O. B. , Mak Yim-Wah , Lam Tai-Hing
Published: June 2008

This study describes the establishment, promotion, and preliminary findings of a peer-led smoking cessation quitline for Chinese youth smokers in Hong Kong. The Youth Quitline targeted Chinese smokers aged 12 to 25, who smoked at least one cigarette in the past 30 days and were willing to leave telephone numbers for follow up. The protocol was translated from the California Smoker's Helpline and we provided toll-free telephone counseling based on motivational intervention with multiple follow-up sessions for smokers who called the service. By intention-to-treat analysis, 55% reported at least one quit attempt, and the quit rate was 22.1% (self-reported 7-day point prevalence) or 17.5% (self-reported 30-day point prevalence). The Hong Kong Youth Quitline, along with enforcement of the antismoking legislation for both youth and adults, advocacy to de-normalize smoking in the society, and appropriate publicity, could help to promote quitting among youth smokers in Hong Kong.
A review of conflict of interest, competing interest, and bias for toxicologists
Authors: Claxton LD
Published: June 2008

One of the issues often associated with scientific misconduct is conflict of interest. Although there is a lack of uniformity in the definition of conflict of interest, many express concerns that competing interests may bias research methods and the interpretation of data and conclusions. In extreme cases, conflict of interest activity could contribute to scientific misconduct, hinder the training of scientists, delay the dissemination of research results, lead to the harming of human health and the environment, and misdirect society’s decisions that rely on science. This article is not a commentary or editorial but an attempt to supply an overview of what has been said, researched, and accomplished in the area of conflict of interest for toxicologists. Discussion of the financial, professional, and philosophical concerns associated with conflict of interest will be followed by brief discussion of general management approaches and the roles of scientists and organizations from all sectors (i.e., academia, industry, non-profit organizations, and government).
Levels of retinyl palmitate and retinol in the skin of SKH-1 mice topically treated with retinyl palmitate and concomitant exposure to simulated solar light for thirteen weeks
Authors: Yan J , Xia Q , Wamer WG , Boudreau MD , Warbritton A , Howard PC , Fu PP
Published: June 2008

Retinyl esters account for more than 70% of the endogenous vitamin A found in human skin, and retinyl palmitate is one of the retinyl esters in this pool. Human skin is also exposed to retinyl palmitate exogenously through the topical application of cosmetic and skin care products that contain retinyl palmitate. To date, there is limited information on the penetration and distribution of retinyl palmitate and vitamin A within in the skin. In this study, the accumulation of retinyl palmitate and generation of retinol in the skin of male and female SKH-1 mice that received repeated topical applications of creams containing 0.0%, 0.1%, 0.5%, 1.0%, 5.0%, 10%, or 13% of retinyl palmitate 5 days a week for a period of 13 weeks were studied. Because products containing retinyl palmitate are frequently applied to sun-exposed skin, and because it is well established that exposure to sunlight and UV light can alter cutaneous levels of retinoids, mice in this study were additionally exposed 5 days a week to simulated solar light. The results showed that retinyl palmitate diffused into the skin and was partially hydrolyzed to retinol. The levels of retinyl palmitate in the skin of mice that were administered retinyl palmitate cream were higher than control values, and levels of both retinyl palmitate and retinol increased with the application of higher concentrations of retinyl palmitate in the cream. Our results indicate that topically applied retinyl palmitate may alter the normal physiological levels of retinyl palmitate and retinol in the skin of SKH-1 mice and may have a significant impact on vitamin A homeostasis in the skin.
The periodontal status of indirectly lead-exposed apprentices working in autorepair workshops
Authors: Yetkin-Ay Z , Çadır B , Uskun E , Bozkurt FY , Delibaş N , Gültepe FM , Ergürhan-İlhan İ
Published: June 2008

The aim of this study was to evaluate the periodontal health status of lead-exposed apprentices and to search the correlation between clinical periodontal parameters and either blood lead or oxidative stress/damage indices in erythrocytes. Sixty male subjects were recruited for this study (30 apprentices and 30 controls). The periodontal health status was determined with gingival index, plaque index, gingival bleeding time index, probing depth, and clinical attachment level records. Additionally, blood lead level and indices of oxidative stress (glutathione peroxidase, superoxide dismutase), catalase activities and damage (malondialdehyde concentration) in erythrocytes were determined. The results showed that lead level was significantly higher in apprentices than in controls ( P < 0.05). None of the clinical periodontal parameters and oxidative stress/damage indices were significantly different between the groups ( P > 0.05). Significant correlation between plaque index and catalase, probing depth and superoxide dismutase, clinical attachment level and superoxide dismutase, and clinical attachment level and malondialdehyde in apprentices group ( P < 0.05), and gingival bleeding time index and glutathione peroxidase in control group were found ( P < 0.05). In multiple regression analysis, there were statistically significant associations between gingival index and working status, family income and either probing depth or clinical attachment level ( P < 0.05). The results of this study showed significant association between the clinical periodontal parameters and oxidative stress/damage indices in apprentices indirectly exposed to low levels of lead.
Parametric Identification and Health Monitoring of Complex Ground Vehicle Models
Authors: Metallidis P. , Stavrakis I. , Natsiavas S.
Published: June 2008

A systematic methodology is applied for performing parametric identification and health monitoring in the suspension substructures of complex vehicle models. The equations of motion are derived by applying a finite element method. As a consequence, they involve quite a large number of degrees-of-freedom (DOF). In addition, they include strongly nonlinear terms. In particular, the main nonlinearities arise due to the function of the suspension dampers and springs. Moreover, the action of the bushings connecting the suspension subsystems to the vehicle body is also strongly nonlinear. Since the resulting number of DOF is large, an appropriate coordinate condensation technique is applied first. This drastically reduces the dimension of the original system and allows the application of a statisticcal system identification methodology, which is effective for dynamical systems with relatively small dimension, in order to perform parametric identification and fault detection studies in the suspension subsystems of an example vehicle model. In the second part of this study, the methodology developed is applied and yields numerical results related to parametric identification and fault detection in the suspensions of the vehicle model examined. The results are found to be sufficiently accurate even in the presence of considerable measurement noise and model errors.
A Multicenter Trial of an Assess-and-Fit Hearing Aid Service Using Open Canal Fittings and Comply Ear Tips
Authors: Smith Pauline , Mack Angela , Davis Adrian
Published: June 2008

Large potential benefits have been suggested for an assess-and-fit approach to hearing health care, particularly using open canal fittings. However, the clinical effectiveness has not previously been evaluated, nor has the efficiency of this approach in a National Health Service setting. These two outcomes were measured in a variety of clinical settings in the United Kingdom. Twelve services in England and Wales participated, and 540 people with hearing problems, not previously referred for assessment, were included. Of these, 68% ( n = 369) were suitable and had hearing aids fitted to NAL NL1 during the assess-and-fit visit using either open ear tips, or Comply ear tips. The Glasgow Hearing Aid Benefit Profile was used to compare patients fitted with open ear tips with a group of patients from the English Modernization of Hearing Aid Services evaluation, who used custom earmolds. This showed a significant improvement in outcome for those with open ear tips after allowing for age and hearing loss in the analysis. In particular, the benefits of using bilateral open ear tips were significantly larger than bilateral custom earmolds. This assess-and-fit model showed a mean service efficiency gain of about 5% to 10%. The actual gain will depend on current practice, in particular on the separate appointments used, the numbers of patients failing to attend appointments, and the numbers not accepting a hearing aid solution for their problem. There are potentially further efficiency and quality gains to be made if patients are appropriately triaged before referral.
Confronting the Past?
Authors: Basu Paul
Published: June 2008

Cultural heritage is not a priority in Sierra Leone. As one of the poorest countries in the world and one only gradually recovering from civil war, there are more immediate concerns. Despite long-term neglect, this article considers whether there is, however, a role for Sierra Leone's cultural heritage in post-conflict recovery. It examines two arenas for the production of Sierra Leone's national past: its list of proclaimed national monuments notionally protected by a Monuments and Relics Commission, and the report of its Truth and Reconciliation Commission (TRC). Whilst the rhetoric of the TRC calls Sierra Leoneans to confront their past, history is rewritten in its report and a mythic past of `peaceful co-existence' posited. To confront Sierra Leone's `indigenous' cultural heritage is, however, to confront a long history of conflict. The article asks whether it is not better to acknowledge this difficult past rather than deny it.
Heritage as Therapy
Authors: Meskell Lynn , Scheermeyer Colette
Published: June 2008

Since the democratic dispensation in South Africa, heritage as a category has been necessarily framed by the specter of the Truth and Reconciliation Commission, its place in wider society, the general underpinnings of amnesty, forgiveness and the desire to move forward as a nation. Human rights activism, truth commissions, and juridical proceedings are powerful mechanisms for dealing with historical trauma. More materially, South African cultural productions, including objects, memorials, museums, heritage sites and public spaces of commemoration provide another therapeutic arena. After 13 years of democracy, the material spaces of daily life provide a vantage point to examine how practices of remembering and forgetting pervade the public sphere and the world of things, and how traumatic embrace is configured to include (and exclude) certain constituencies as our case studies demonstrate. Spectacles of trauma and memory in the new South Africa are similarly shot through with other interventions including the pressures of state politics, development tactics and international tourism. Perhaps like never before, this `state in search of a nation', has been under an international spotlight and has been held up as a beacon for other oppressive contexts and post-conflict states.
Understanding the Dynamics of Collective Learning: The Role of Trust and Social Capital
Authors: Gubbins Claire , MacCurtain Sarah
Published: June 2008

The problem and the solution. A focus on collective, as opposed to individual learning, points to the social network component of learning. Collective learning is fundamentally concerned with social interaction and the development of relational synergies.A key challenge to understanding social interaction is the influence of trust. Trust is important for social capital development and thus for collective learning.This article addresses a significant gap in the literature by reviewing the literature on collective learning, trust, and social capital theory and proposing a set of propositions for further research.The article also identifies a number of implications for HRD in tandem with each proposition.
Team Learning and Metacognition: A Neglected Area of HRD Research and Practice
Authors: McCarthy Alma , Garavan Thomas N.
Published: June 2008

The problem and the solution. An important and somewhat neglected level of analysis in human resource development research and practice is learning and development that occurs within a team. Increasingly, teams are required to make important decisions in organizations. Employees must learn to be team members and to function not merely as a collective of individuals, but rather as a cohesive team that learns to learn. A key component of team learning concerns metacognitive processes. Although metacognition has been established as an important aspect of individual level learning, there is a paucity of research exploring how metacognition can impact learning at a team and collective level. We propose a conceptual model of team learning and metacognition and discuss the implications for research and practice.
Gossypol, a BH3 mimetic, induces apoptosis in chronic lymphocytic leukemia cells
Authors: Balakrishnan Kumudha , Wierda William G. , Keating Michael J. , Gandhi Varsha
Published: June 2008

Gossypol, a cottonseed extract derivative, acts as a BH3-mimetic, binding to the BH3 pocket of antiapoptotic proteins and displacing pro-death partners to induce apoptosis. However, knowledge on the molecular underpinnings of its downstream effects is limited. Since chronic lymphocytic leukemia (CLL) cells express high levels of antiapoptotic proteins that act as a survival mechanism for these replicationally quiescent lymphocytes, we investigated whether gossypol induces apoptosis in these cells and what mechanism underlies gossypol-mediated cytotoxicity. Gossypol induced cell death in a concentration- and time-dependent manner; 24-hour incubation with 30 μM gossypol resulted in 50% cell death (median; range, 10%-80%; n = 47) that was not abrogated by pan-specific caspase inhibitor. Starting at 4 hours, the mitochondrial outer membrane was significantly permeabilized (median, 77%; range, 54%-93%; n = 15). Mitochondrial outer membrane permeabiliztaion (MOMP) was concurrent with increased production of reactive oxygen species (ROS); however, antioxidants did not abrogate gossypol-induced cell death. Mitochondrial membrane permeabilization was also associated with loss of intracellular adenosine triphosphate (ATP), activation of BAX, and release of cytochrome c and apoptosis-inducing factor (AIF), which was translocated to the nucleus. Blocking AIF translocation resulted in a decreased apoptosis, suggesting that AIF contributes to gossypol-mediated cytotoxicity in CLL lymphocytes.
Leukemic transformation in mice expressing a NUP98-HOXD13 transgene is accompanied by spontaneous mutations in Nras, Kras, and Cbl
Authors: Slape Christopher , Liu Leah Y. , Beachy Sarah , Aplan Peter D.
Published: June 2008

The NUP98-HOXD13 (NHD13) fusion gene occurs in patients with myelodysplastic syndrome (MDS) and acute nonlymphocytic leukemia (ANLL). We reported that transgenic mice expressing NHD13 develop MDS, and that more than half of these mice eventually progress to acute leukemia. The latency period suggests a requirement for at least 1 complementary event before leukemic transformation. We conducted a candidate gene search for complementary events focused on genes that are frequently mutated in human myeloid leukemia. We investigated 22 ANLL samples and found a high frequency of Nras and Kras mutations, an absence of Npm1, p53, Runx1, Kit and Flt3 mutations, and a single Cbl mutation. Our findings support a working hypothesis that predicts that ANLL cases have one mutation which inhibits differentiation, and a complementary mutation which enhances proliferation or inhibit apoptosis. In addition, we provide the first evidence for spontaneous collaborating mutations in a genetically engineered mouse model of ANLL.