bluuebunny/crossref_metadata_2025_split huggingface dataset:
Modeling the Distribution of Precipitation Forecasts from the Canadian Ensemble Prediction System Using Kernel Density Estimation
Authors: Peel Syd , Wilson Laurence J. 
Published: August 2008

AbstractKernel density estimation is employed to fit smooth probabilistic models to precipitation forecasts of the Canadian ensemble prediction system. An intuitive nonparametric technique, kernel density estimation has become a powerful tool widely used in the approximation of probability density functions. The density estimators were constructed using the gamma kernels prescribed by S.-X. Chen, confined as they are to the nonnegative real axis, which constitutes the support of the random variable representing precipitation accumulation.Performance of kernel density estimators for several different smoothing bandwidths is compared with the discrete probabilistic model obtained as the fraction of member forecasts predicting the events, which for this study consisted of threshold exceedances. A propitious choice of the smoothing bandwidth yields smooth forecasts comparable, or sometimes superior, to the discrete probabilistic forecast, depending on the character of the raw ensemble forecasts. At the same time more realistic models of the probability density are achieved, particularly in the tail of the distribution, yielding forecasts that can be optimally calibrated for extreme events.
The Application of an Evolutionary Algorithm to the Optimization of a Mesoscale Meteorological Model
Authors: O’Steen Lance , Werth David 
Published: August 2008

Abstract
It is shown that a simple evolutionary algorithm can optimize a set of mesoscale atmospheric model parameters with respect to agreement between the mesoscale simulation and a limited set of synthetic observations. This is illustrated using the Regional Atmospheric Modeling System (RAMS). A set of 23 RAMS parameters is optimized by minimizing a cost function based on the root-mean-square (rms) error between the RAMS simulation and synthetic data (observations derived from a separate RAMS simulation). It is found that the optimization can be done with relatively modest computer resources; therefore, operational implementation is possible. The overall number of simulations needed to obtain a specific reduction of the cost function is found to depend strongly on the procedure used to perturb the “child” parameters relative to their “parents” within the evolutionary algorithm. In addition, the choice of meteorological variables that are included in the rms error and their relative weighting are also found to be important factors in the optimization.
“Warm Rain” in the Tropics: Seasonal and Regional Distributions Based on 9 yr of TRMM Data
Authors: Liu Chuntao , Zipser Edward J. 
Published: August 2008

Abstract
How much precipitation is contributed by warm rain systems over the tropics? What is the typical size, intensity, and echo top of warm rain events observed by the Tropical Rainfall Measuring Mission (TRMM) Precipitation Radar over different regions of the tropics? What proportion of warm raining areas is actually attached to the edges of cold systems? Are there mesoscale warm raining systems, and if so, where and when do they occur? To answer these questions, a 9-yr TRMM precipitation feature database is used in this study. First, warm rain features in 20°S–20°N are selected by specifying precipitation features 1) with minimum infrared brightness temperature &gt; 0°C, 2) with TRMM Precipitation Radar (PR) echo top below freezing level, or 3) without any ice-scattering signature in the microwave observations, respectively. Then, the geographical, seasonal, and diurnal variations of the rain volume inside warm rain features defined in these three ways are presented. The characteristics of warm rain features are summarized.
Raining pixels with cloud-top temperature above 0°C contribute 20% of the rainfall over tropical oceans and 7.5% over tropical land. However, about half of the warm pixels over oceans and two-thirds of the warm pixels over land are attached to cold precipitation systems. A large amount of warm rainfall occurs over oceans near windward coasts during winter. Most of the warm rain systems have small size &lt; 100 km2 and weak radar echo with a modal maximum near-surface reflectivity around 23 dBZ. However, mesoscale warm rain systems with strong radar echoes do occur in large regions of the tropical oceans, more during the nighttime than during daytime. Though the mean height of the warm precipitation features over oceans is lower than that over land, there is no significant regional difference in its size and intensity.
Forward-Looking Assimilation of MODIS-Derived Snow-Covered Area into a Land Surface Model
Authors: Zaitchik Benjamin F. , Rodell Matthew 
Published: August 2008

Abstract
Snow cover over land has a significant impact on the surface radiation budget, turbulent energy fluxes to the atmosphere, and local hydrological fluxes. For this reason, inaccuracies in the representation of snow-covered area (SCA) within a land surface model (LSM) can lead to substantial errors in both offline and coupled simulations. Data assimilation algorithms have the potential to address this problem. However, the assimilation of SCA observations is complicated by an information deficit in the observation—SCA indicates only the presence or absence of snow, not snow water equivalent—and by the fact that assimilated SCA observations can introduce inconsistencies with atmospheric forcing data, leading to nonphysical artifacts in the local water balance. In this paper, a novel assimilation algorithm is presented that introduces Moderate Resolution Imaging Spectroradiometer (MODIS) SCA observations to the Noah LSM in global, uncoupled simulations. The algorithm uses observations from up to 72 h ahead of the model simulation to correct against emerging errors in the simulation of snow cover while preserving the local hydrologic balance. This is accomplished by using future snow observations to adjust air temperature and, when necessary, precipitation within the LSM. In global, offline integrations, this new assimilation algorithm provided improved simulation of SCA and snow water equivalent relative to open loop integrations and integrations that used an earlier SCA assimilation algorithm. These improvements, in turn, influenced the simulation of surface water and energy fluxes during the snow season and, in some regions, on into the following spring.
Theory and Characterization of Weather Radar Networks
Authors: Junyent Francesc , Chandrasekar V. 
Published: August 2008

Abstract
A dense weather radar network is an emerging concept advanced by the Engineering Research Center for Collaborative Adaptive Sensing of the Atmosphere (CASA). In a weather radar environment, the specific radar units employed and the network topology will influence the characteristics of the data obtained. To define this, a general framework is developed to describe the radar network space, and formulations are obtained that can be used for weather radar network characterization.
The models developed are useful for quantifying and comparing the performance of different weather radar networks. Starting with system characteristics that are used to specify individual radars, a theoretical basis is developed to extend the concept to network configurations of interest. A general network elemental cell is defined and employed as the parameterized domain over which different coverage aspects (such as detection sensitivity, beam size, and minimum beam height) are studied using analytical tools developed in the paper. Other important parameters are the number of different radars with overlapping coverage at a given point in the network domain and the coverage area and number of radars of a network and its elemental cells. A combination of analytical and numerically derived expressions is employed to obtain these parameters for several configurations.
The radar network characterization tools developed are applied to the comparison of individual radar and networked radar configurations of interest. The values used in the calculations illustrate the CASA Integrated Project 1 (IP1) radar network and are compared to other radar systems.
Detecting Source Regions of Wave Activities in the Tropical Atmosphere by Applying Beamforming to Interpolated Data Grids
Authors: Hu Qi , Liang Zhaoning , Hoffman Michael W. 
Published: August 2008

Abstract
Wave activities are primary sources of weather disturbances and cyclones in the tropical atmosphere. One such activity is the intraseasonal variations in wind, convection, and precipitation in the tropical Indian and western tropical Pacific region. These variations affect the intensity, break and reset, and rainfall in the Indian and the East Asian monsoons. Detecting the source regions of these wave activities is essential for understanding and for prediction of wave development. In this study, a fixed beamforming method is proposed to deduce source regions of some wave activities in the tropical atmosphere. This method is tested with simulations of single and distributed complex sources of waves and, then, fixed beamformers are applied to the ECMWF interpolated data grids to detect and identify source regions of the intraseasonal oscillations–waves in the tropical Indian and tropical Pacific Ocean region. Results show that the fixed beamforming technique can uniquely identify the source regions of the intraseasonal oscillations. Applications of this method have revealed various source regions of all major intraseasonal oscillation (ISO) events in the tropical Indian and western equatorial Pacific region during the 29 yr from 1974 to 2002. Knowing these source regions will make it possible to extract the relevant information and, thus, to better understand the development of the intraseasonal oscillations as well as their effects on the tropical weather and climate.
Treating each and every depressed patient
Authors: Kennedy SH 
Published: August 2008

Abstract Major depressive disorder (MDD) is a prevalent condition with substantial heterogeneity in terms of clinical symptom profiles, overlapping syndromes and degree of severity. The challenge for any new antidepressant is to demonstrate efficacy across the spectrum of patient subpopulations with a diagnosis of MDD. The anxious depressed patient historically has a lower rate of response to traditional antidepressants and high pretreatment anxiety symptoms have also been shown to increase the risk of recurrence. In addition, severity based on standard antidepressant rating scale scores influences treatment outcomes. Some antidepressants display greater placebo separation at higher levels of severity while others fail to separate from placebo in more severe populations. Gender differences in antidepressant response have also been reported in several studies. In particular, women appear to experience a greater side-effect burden with current antidepressants. This is also important in treating late-life depression, where elderly patients are more prone to experiencing side effects and drug interactions. Despite the improved tolerability with SSRIs and other novel antidepressants, restoration of healthy sleep patterns has frequently been lacking. Finally, antidepressant efficacy must include demonstrated relapse prevention during placebo-controlled drug discontinuation trials. As a novel antidepressant with melatonin receptor agonist and 5HT2C antagonist properties, agomelatine has demonstrated efficacy in randomized placebo-controlled trials. Additional analyses support the benefits of agomelatine in anxious depression, increasing efficacy with greater baseline severity, including severe late-life depression. Agomelatine has also demonstrated favourable tolerability and efficacy in separate analyses of women and men and displays successful relapse prevention at doses 25 and 50 mg. Both subjective and polysomnographic measures of sleep support increased sleep efficiency and decreased awakenings during agomelatine treatment. Combining these efficacy data with favourable effects on sexual function, CNS and GI systems, there are grounds to endorse the view that agomelatine is a well-tolerated and efficacious antidepressant for a diverse range of depressed populations.
Short Term Equity Returns of Chinese IPOs, 1999 to 2004
Authors: Li Larry , Fowler John , Naughton Tony 
Published: August 2008

Our study of 531 Initial Public Offerings (IPOs) on the two Chinese Stock Exchanges during the period 1999 to 2004 indicates initial returns to investors of approximately 114.04 per cent and these earnings were sustained through the first month of trading. High initial returns on IPOs are most often characterised as a reflection of state policy acting with a view to longer-term economic gains and sound social policy. The sample IPOs were found to be oversubscribed by 243 times the share offered. Such a level of excess demand is a major factor in high initial returns to Chinese IPOs. Regression analysis indicated other major factors associated with these high initial returns including company size, offer size, general market conditions in the period of lead up to the first listing, the proportion of tradable-A shares available and the signal PE ratio at the time of offer. In addition, the paper emphasises the potential for very significant wealth effects, capital formation and development of a private capital market which arises from private sector gains linked to the IPOs.
B lymphocytes: how they develop and function
Authors: LeBien Tucker W. , Tedder Thomas F. 
Published: August 2008

AbstractThe discovery that lymphocyte subpopulations participate in distinct components of the immune response focused attention onto the origins and function of lymphocytes more than 40 years ago. Studies in the 1960s and 1970s demonstrated that B and T lymphocytes were responsible primarily for the basic functions of antibody production and cell-mediated immune responses, respectively. The decades that followed have witnessed a continuum of unfolding complexities in B-cell development, subsets, and function that could not have been predicted. Some of the landmark discoveries that led to our current understanding of B lymphocytes as the source of protective innate and adaptive antibodies are highlighted in this essay. The phenotypic and functional diversity of B lymphocytes, their regulatory roles independent of antibody production, and the molecular events that make this lineage unique are also considered. Finally, perturbations in B-cell development that give rise to certain types of congenital immunodeficiency, leukemia/lymphoma, and autoimmune disease are discussed in the context of normal B-cell development and selection. Despite the significant advances that have been made at the cellular and molecular levels, there is much more to learn, and cross-disciplinary studies in hematology and immunology will continue to pave the way for new discoveries.
Selective Partial Hydrogenation of Dinitrobenzenes to Nitroanilines Catalyzed by Ru/C
Authors: Hou Jie , Ma Yonghuan , Li Yuhan , Guo Fang , Lu Lianhai 
Published: August 2008

Abstract
Ru/C was found to be a highly effective catalyst for the selective partial hydrogenation of a range of dinitrobenzenes to their corresponding nitroanilines with excellent selectivity under mild conditions. Furthermore, the effect from other substitute groups of dinitrobenzenes on partial hydrogenation was also explored in this study.
Silicon-based Synthesis of [2]Rotaxanes without Polar Functional Groups
Authors: Phan Son Thanh , Setaka Wataru , Kira Mitsuo 
Published: August 2008

Abstract
The synthesis of [2]rotaxanes without polar functional groups was achieved by protodesilylation of the corresponding phenylene-bridged 1,12-disilacyclodocosanes in 20–30% isolated yields. The molecular structure of rotaxane 1a showed that the wheel is not at the center of the rod but on a dimethylene group of the dumbbell. By detailed NMR analyses, facile shuttling of the wheel was found to control the geometry of the dumbbells in the rotaxanes.
Synthesis and Characterization of Starburst 9-Phenylcarbazole/Triazatruxene Hybrids
Authors: Lai Wen-Yong , He Qi-Yuan , Chen Dao-Yong , Huang Wei 
Published: August 2008

Abstract
Novel starburst triazatruxenes functionalized with six N-phenylated carbazole units have been synthesized and characterized. Good yields and high purity were readily obtained via an optimized microwave-enhanced six-fold Suzuki coupling methodology. High thermal stability and good amorphous properties as well as deep blue emissions (423–434 nm) were demonstrated. The introduction of six-substituted triazatruxene scaffolds could provide a new guideline for exploring novel solution-processable amorphous materials with dual functions for light-emitting and/or hole-transporting applications.
Preparation of Hydrolyzable Polyrotaxane Containing Ester Linkages and Its Degradation Behavior
Authors: Katoono Ryo , Fukuda Shin-ichiroh , Shin Hojoon , Yui Nobuhiko 
Published: August 2008

Abstract
A hydrolyzable polyrotaxane composed of an ester-containing poly(ethylene glycol) chain and α-cyclodextrins showed gradual degradation into its water-soluble components in aqueous conditions, based on the dissociation of the polyrotaxane triggered by the hydrolysis of the ester groups.
Effects of O3 and NO2 on Catalytic Oxidation of Diesel PM
Authors: Yamamoto Shin , Yao Shuiliang , Kodama Satoshi , Mine Chieko , Fujioka Yuichi 
Published: August 2008

Abstract
Oxidative activities of ten different catalysts to particulate matter (PM) emitted from a diesel engine have been compared by thermogravimetric analysis under an atmosphere containing O3 and NO2. MnO2 has been found to exceed noble metal catalysts in the PM oxidation efficiency even at 300 °C. The PM oxidative activities of transition-metal oxides possessing high formation enthalpies are enhanced by the active oxygen species owing to acceleration of redox catalytic cycles.
Incomplete laboratory request forms: the extent and impact on critical results at a tertiary hospital in South Africa
Authors: Nutt Louise , Zemlin Annalise E , Erasmus Rajiv T 
Published: August 2008

Background Research has demonstrated that most laboratory errors occur in the preanalytical phase of testing. In view of the paucity of studies examining preanalytical errors, we evaluated our laboratory request forms for the frequency and impact of incomplete data. Methods This study examined all request forms received at our laboratory during a five-day period. The forms were scrutinized for the presence of specific parameters. The impact of abbreviated diagnoses was analysed, as well as how lack of ward or telephone details affects the communication of critical results to clinicians. Results A total of 2550 request forms were analysed. Medication(s) used by the patient (89.6%) and doctor’s contact number (61.2%) were the most incomplete parameters. No diagnosis was provided on 19.1% of forms, and when a diagnosis was present it was an abbreviated form in 37.3%. This resulted in 35.5% of diagnoses not being recorded by reception staff. Incomplete ward information was found on 4.9% of forms. In a separate search, the impact of 151 request forms (collected over a period of eight months), with incomplete ward location information and corresponding to critical results was assessed. Critical results were not communicated by telephone to clinicians in 19.9% of cases. Conclusion As laboratory data influences 70% of medical diagnoses, incorrect or incomplete data provided to the laboratory could significantly impact the success and cost of overall treatment.
Role of conformational change in the C-terminus of β2-microglobulin in dialysis-related amyloidosis
Authors: Kim Jaemi , Motomiya Yoshihiro , Ueda Mitsuharu , Nakamura Masaaki , Misumi Yohei , Saito Shiori , Ikemizu Shinji , Misumi Shogo , Ota Kazutoshi , Shinriki Satoru , Kai Hirofumi , Ando Yukio 
Published: August 2008

Background β2-Microglobulin (β2m) has been identified as the precursor protein of dialysis-related amyloidosis (DRA), which is a serious complication for haemodialysis (HD) patients. However, mechanisms underlying β2m amyloid fibril formation remains to be elucidated. We previously demonstrated, in amyloid deposits from HD patients, a conformational isoform of β2m with an unfolded C-terminus. However, no direct experiments have previously been performed to address whether unfolded β2m in the C-terminus may be prone to form amyloid fibrils. Methods To evaluate roles of C-terminal amino acids in β2m-induced amyloid formation, we generated six types of recombinant β2m with amino acid substitutions in the C-terminal region. To investigate their conformational change and amyloidogenicity, we measured circular dichroism spectra, the fluorescence intensity of tryptophan and thioflavin-T (ThT) of the recombinant β2m. To analyse morphological change of β2m, we performed electron microscopy (EM) on the samples with elevated ThT fluorescence intensity. We used ultrasonication to enhance β2m destabilization of the protein. Results β2M Trp95Leu and Arg97Ala showed conformational changes and increased their amyloidgenicity compared with β2m wild-type (WT). With ultrasonication, β2m Trp95Leu and Arg97Ala generated more amyloid fibrils than did β2m WT even in physiological solution. EM showed that β2m formed amorphous debris containing typical amyloid fibrils at 24 hours, when ThT fluorescence intensity was three-fold lower than that at six hours. Conclusions Conformational changes in the C-terminus of β2m may play an important role in DRA and that ultrasonication is useful for analysis of β2m amyloidogenesis.
Independent clinical predictors of impaired response to hepatitis B vaccination in HIV-infected persons
Authors: Kim H Nina , Harrington Robert D , Van Rompaey Stephen E , Kitahata Mari M 
Published: August 2008

Summary: Protective response rates to hepatitis B (HB) vaccination have been reported as low as 18-62% in HIV-infected persons. The relative importance of various predictors for this poor response has not been fully characterized. In this retrospective cohort study, we examined the relationship between clinical characteristics and vaccine non-response (HB surface antibody <10 IU/L) among patients attending an urban HIV clinic. Among the 97 patients who met the inclusion criteria, 43 (44%) developed a protective antibody response. In multivariate analyses, age >40 years (odds ratio [OR] 3.03 [95% confidence interval [CI], 1.14-8.06]; P = 0.026) and alcohol abuse (OR 4.92 [95% CI, 1.72-20.89]; P = 0.007) were independent predictors of failure to develop vaccine response. In addition, CD4 nadir <200 (OR 7.24 [95% CI, 1.91-27.41]; P = 0.004), rather than CD4 current to vaccination, remained a strong independent risk factor. Patients with HIV viral suppression on highly active antiretroviral therapy had a significantly lower rate of vaccine failure (OR 0.31 [95% CI, 0.11-0.91]; P = 0.033), after adjusting for these other covariates. Our findings underscore the importance of confirming seroconversion after HB vaccination in HIV-infected patients and initiating vaccination early in the course of HIV infection.