bluuebunny/crossref_metadata_2025_split huggingface dataset:
Influence of contact time on the extraction of 233uranyl spike and contaminant uranium from Hanford Site sediment
Authors: Smith Steven C. , Szecsody James E. 
Published: August 2011

Abstract
The development of effective remediation strategies requires a comprehensive understanding of contaminant behavior in the environment. At the Hanford Site, located in southeastern Washington State (United States of America), seasonal fluctuations of the nearby Columbia River cause flushing of the 300 Area uranium (U) plume in the lower vadose zone. The variation of water chemistry alternately promotes adsorption and desorption of U from sediment. Therefore, the following question arises: what is the mobility of U in groundwater that has only recently became associated with sediment relative to U that has been associated with the sediment for decades? Geochemical transformations, including surface complexation, precipitation, and/or physical processes will impact U speciation as the contact time with sediment increases. To investigate this question, dissolved 233uranyl nitrate [UO2(NO3)2] was added to U-contaminated Hanford Site sediment and incubated for up to 1 year. Following 1-week, 1-month, and 1-year incubation periods, the extraction of U from the sediment was accomplished using either batch or continuous leach techniques, and multiple extractants. The elution of 233U during continuous leaching was influenced by the incubation period. The change in the 235U/233U ratio eluted was indicative of the extraction of different U phases, and was a function of the incubation period. Removal of 233U by batch extraction clearly showed the effects of the incubation period and extractant. The extractability of the 233U spike by some extractants is independent of incubation period (up to 1 year) suggesting it is present as either sorbed or surface precipitate phases. Model simulation of the data provides insight into the processes involved with the extraction of U from the sediment.
Luminescence study on the solvation of Cm(III) in binary aqueous solvent mixtures
Authors: Trumm S. , Lieser G. , Panak Petra J. 
Published: August 2011

AbstractThe preferential solvation of Cm(III) in binary aqueous mixtures of MeOH,tBuOH, DMSO, MeCN and acetone is studied at varied solvent composition. Solvation is investigated by time-resolved laser fluorescence spectroscopy and emission spectra and fluorescence lifetime data are obtained. At high mole fractions of organic solvent, preferential solvation of Cm(III) increases in the order: Me2CO <tBuOH ≈ MeOH < MeCN < H2O < DMSO. Thermodynamic data are derived from the spectroscopic results showing small positive standard Gibbs energies for the transfer of Cm(III) into the various solvent mixtures except for DMSO mixtures where negative values are found. The spectroscopically obtained enthalpies of transfer are fitted to a solvation model using the model parameters Δ Δ Hº12and (αn+βN)º, rendering valuable information on the interaction of Cm(III) with the solvent molecules. Cm(III)-solvent interaction increases in the order:tBuOH < MeCN < MeOH < DMSO.
Update on 67Cu half-life
Authors: Kozempel Ján , Bulgheroni Antonio , Simonelli Federica , Holzwarth Uwe , Abbas Kamel , Gibson Neil 
Published: August 2011

Abstract
The half-life of 67Cu was newly determined by measurement of its 185 keV γ-ray (48.7%) over the period of 13 d (approx. 5 × T
1/2). 67Cu was prepared by deuteron irradiation of enriched 70Zn targets. The 67Cu half-life value which resulted from five independent measurements is estimated to be 61.81(22) h.
A ‘cold’ actinide partitioning run at 20 L scale with hollow fibre supported liquid membrane using diglycolamide extractants
Authors: Ansari S. A. , Gujar R. B. , Mohapatra P. K. , Kandwal Pankaj , Sengupta A. , Thulasidas S. K. , Manchanda V. K. 
Published: August 2011

Abstract
‘Actinide partitioning’ studies were attempted by hollow fibre supported liquid membrane (HFSLM) technique using pressurized heavy water reactor simulated high level waste (PHWR-SHLW) as the feed. Two diglycolamide extractants for actinide partitioning, viz. 0.1 M TODGA (N,N,N´,N´-tetraoctyl diglycolamide) + 0.5 M DHOA (N,N-dihexyl octanamide) and 0.2 M T2EHDGA (N,N,N´,N´-tetra-2-ethylhexyl diglycolamide) + 30% iso-decanol in n-dodecane were used as the carrier solvent. Quantitative recovery of all trivalent actinides and lanthanides from PHWR-SHLW was achieved with both the carriers within 30 min when the feed volume was 0.5 L. On the other hand, about 18 h were necessary for a similar study carried out using a feed volume of 20 L. None of the other elements present in the PHWR-SHLW were transported, except small quantities of Sr and Mo. The product could be concentrated to two and four times by maintaining the feed to receiver phase volume ratio of 2:1 and 4:1, respectively. The transport behaviour of trivalent actinides and lanthanides by the two diglycolamide extractants were remarkably similar. The present studies revealed that diglycolamide-HFSLM system offers a promising alternative approach for ‘actinide partitioning’, where the use of organic solvent inventory could be drastically reduced. A mathematical model was developed and there was good agreement between the predicted and experimentally obtained data.
Environmental behavior of ZrO2-MgO ceramics containing UO2
Authors: Holliday K. S. , Hartmann T. , Cerefice G.S. , Czerwinski K. 
Published: August 2011

Abstract
In this study a ZrO2-MgO inert matrix fuel containing UO2 (a PuO2 homolog) and Er2O3 (burnable poison) was evaluated under environmental conditions to assess its performance as a waste form should a direct disposal scheme be adopted. A Soxhlet degradation study was used to assess the durability of the ceramic in contact with water for 2000 h over a range of ZrO2 to MgO ratios. This quantified the amount of ZrO2 required to stabilize the material against degradation. A pulse flow dissolution study was used to investigate the stability of the material in aqueous environments relevant to a repository. Although the MgO phase was dissolved, the material was found to retain Zr, U, and Er oxides while immersed in brine, silicate-bicarbonate solution, or deionized water for 3700 h. Aqueous media with a high level of silicate formed a Mg2SiO4 phase at the surface, which retarded further degradation of the material. Brine was found to be the most aggressive solution in altering the material. The data provides an evaluation of the mixed inert matrix behavior under a range of potential repository conditions.
Activation cross-section measurements of some proton induced reactions on Ni, Co and Mo for proton activation analysis (PAA) purposes
Authors: Alharbi A. A. , Alzahrani J. , Azzam A. 
Published: August 2011

Abstract
The experimental proton induced reaction cross sections on some elements of the Havar alloy were measured using the activation method and the well established stacked-foil technique combined with high resolution gamma-ray spectroscopy. They included the reactions natNi(p,x)57Ni, natCo(p,x)58(m+g)Co and natMo(p,x)94g,95g,96(m+g)Tc, the aim being to obtain reliable data in the proton energy range up to 26 MeV for some important reactions to be used in the proton activation analysis of steel or other alloys. Irradiations were performed using the CS-30 Cyclotron at KFSH and RC, Riyadh, Saudi Arabia. The activity measurements were carried out in PNU laboratories, Riyadh, Saudi Arabia. The experimental excitation functions for the investigated reactions were constructed and compared with the performed computed theoretical nuclear model calculations using two different codes: ALICE-IPPE and TALYS. A comparison between our measured cross-section values and the available published data is also presented, with a view to checking the consistency of the reported experimental work from various laboratories.
Neutron activation analysis and atomic absorption spectrophotometry for the analysis of fresh, pasteurised and powder milk
Authors: Wasim Mohammad , Rehman S. , Arif Mohammad , Fatima I. , Zaidi Jamshed Hussain 
Published: August 2011

Abstract
This study shows the application of semi-absolute k
0 instrumental neutron activation analysis (k
0-INAA), epithermal neutron activation analysis (ENAA) and atomic absorption spectrophotometry (AAS) for the determination of 21 elements (Br, Ca, Cl, Co, Cr, Cs, Cu, Fe, Hf, I, K, Mg, Mn, Na, Ni, P, Pb, Rb, Sc Sr, and Zn) in different types of milk samples. The ENAA was required for the determination of iodine, AAS for Cu, Ni and Pb and the rest of the elements were measured by k
0-INAA. Thirteen elements (Br, Ca, Cl, Cs, Cu, Fe, K, Mg, Na, P, Rb, Sr and Zn) were identified in all milk samples. Ni was detected in eleven and Pb in two samples. Concentrations of most of the elements were within the ranges of the world reported data. The data was further explored by principal component analysis to find relationships between samples and elements.
Relaxation Dynamics of Electronically Excited C60
− in o-Dichlorobenzene and Tetrahydrofuran Solution
Authors: Brands Helge , Ehrler Oli T. , Kappes Manfred , Unterreiner Andreas-Neil 
Published: August 2011

Abstract
The ultrafast response of singly negatively charged C60 fullerene in solution has been investigated by femtosecond pump-probe absorption spectroscopy and transient anisotropy in the visible and near-infrared region. Pump excitation within the near-infrared band demonstrates that this spectral feature can be described as a vibrational progression associated with a single electronic transition. Relaxation of the first electronically excited state occurs primarily by internal conversion with a time constant of 3 ps, slightly depending on the solvents, tetrahydrofuran or o-dichlorobenzene, and also on the excitation wavelength. An excitation of the second electronically excited state around 530 nm leads to an ultrafast internal conversion to the first excited state with a pulse-limited time constant of less than 100 fs. As a minor channel, stimulated emission in the spectral regime of 1150–1300 nm was observed from the first electronically excited state both after near-infrared and visible excitation. After internal conversion to the electronic ground state, C60
− dissipates its excess internal energy into the solvent on a longer timescale of 40–70 ps. The transient anisotropy associated with directly populating the first excited state reveals an ultrafast component decaying within 100 fs, which is attributed to ultrafast vibrational motions, conceivably arising from excited state pseudorotation.
Experimental and Modelling Study of the Unimolecular Thermal Decompostion of CHF3
Authors: Cobos Carlos J. , Croce A. E. , Luther K. , Troe Hans-Jürgen 
Published: August 2011

Abstract
The unimolecular thermal decomposition reaction CHF3 (+M)→CF2 + HF (+M) was studied in shock waves by monitoring the UV absorption of the forming CF2 radicals. The results of the present and previous experiments on the temperature and pressure dependence of the rate constants are analyzed in terms of unimolecular rate theory. Falloff curves (for 1500–1900 K) are represented in terms of fitted limiting low pressure rate constants k
0 = [Ar] 1.1 × 1016exp(−53.0 kcal mol−1/RT) cm3mol−1s−1, limiting high pressure rate constants k
∞ = 1.25 × 1015 exp(−75.8 kcal mol−1/RT) s−1 from quantum-chemical calculations, and center broadening factors F
cent = 0.170(± 0.04) including strong and weak collision contributions from unimolecular rate theory. With these results, approximate analytical expressions of the falloff curves well represent the measured and calculated rate constants over wide ranges of pressure and temperature.
Interleukin‐33 Levels in Gingival Crevicular Fluid, Saliva, or Plasma Do Not Differentiate Chronic Periodontitis
Authors: Buduneli Nurcan , Özçaka Özgün , Nalbantsoy Ayşe 
Published: August 2011

Background: This study investigates whether gingival crevicular fluid (GCF), saliva, and plasma levels of interleukin‐33 (IL‐33) can differentiate individuals with chronic periodontitis from individuals with healthy periodontium.Methods: GCF, whole saliva, and plasma samples together with full‐mouth clinical periodontal recordings were obtained from 32 otherwise healthy, non‐smoker chronic periodontitis individuals and 25 systemically and periodontally healthy, non‐smoker individuals. IL‐33 levels in the biofluid samples were determined by enzyme‐linked immunosorbent assay. Data were tested statistically by Mann‐Whitney U test.Results: The GCF concentrations of IL‐33 were significantly lower in chronic periodontitis individuals than in healthy individuals (P <0.0001), whereas the total amounts in GCF samples were similar (P >0.05). The salivary and plasma contrations of IL‐33 were indifferent in the two study groups (P >0.05).Conclusions: According to the present findings, the GCF, saliva or plasma levels of IL‐33 could not differentiate chronic periodontitis individuals and periodontally healthy individuals. Larger‐scale intervention studies may better clarify this issue.
Validity of Partial Protocols to Assess the Prevalence of Periodontal Outcomes and Associated Sociodemographic and Behavior Factors in Adolescents and Young Adults
Authors: Peres Marco A. , Peres Karen G. , Cascaes Andreia M. , Correa Marcos B. , Demarco Flávio F. , Hallal Pedro C. , Horta Bernardo L. , Gigante Denise P. , Menezes Ana B. 
Published: August 2011

Background: Most studies comparing prevalence of periodontal disease and risk factors by using partial protocols were performed in adult populations, with several studies being conducted in clinical settings. The aim of this study is to assess the accuracy of partial protocols in estimating the prevalence of periodontal outcomes in adolescents and young adults from two population‐based birth cohorts from Pelotas, Brazil, and to assess differences in the estimation and strength of the effect measures when partial protocols are adopted compared to full‐mouth examination.Methods: Gingival bleeding at probing among adolescents (n = 339) and young adults (n = 720) and dental calculus and periodontal probing depth among young adults were assessed using full‐mouth examinations and four partial protocols: Ramfjord teeth (RT), community periodontal index (CPI), and two random diagonal quadrants (1 and 3, 2 and 4). Socioeconomic, demographic, and periodontal health–related variables were also collected. Sensitivity, absolute and relative bias, and inflation factors were calculated. Prevalence ratio for each periodontal outcome for the risk factors was estimated.Results: Two diagonal quadrants showed better accuracy; RT had the worst, whereas CPI presented an intermediate pattern when compared to full‐mouth examination. For bleeding assessment in adolescence, RT and CPI underestimated by 18.4% and 16.2%, respectively, the true outcome prevalence, whereas among young adults, all partial protocols underestimated the prevalence. All partial protocols presented similar magnitude of association measures for all investigated periodontal potential risk factors.Conclusion: Two diagonal quadrants protocol may be effective in identifying the risk factors for the most relevant periodontal outcomes in adolescence and in young adulthood.
Effects of Non‐Surgical Periodontal Treatment on Clinical Response, Serum Inflammatory Parameters, and Metabolic Control in Patients With Type 2 Diabetes: A Randomized Study
Authors: Chen Lei , Luo Gang , Xuan Dongying , Wei Bihong , Liu Fang , Li Jing , Zhang Jincai 
Published: August 2011

Background: Scientific evidence on the effects of chronic periodontitis on diabetes mellitus remains inadequate and inconclusive. This intervention study is designed to evaluate the effects of periodontal treatment on clinical response, systemic inflammatory parameters, and metabolic control in patients with Type 2 diabetes.Methods: A total of 134 patients were randomly allocated into two treatment groups and one control group. Treatment group 1 underwent non‐surgical periodontal treatment at baseline and additional subgingival debridement at the 3‐month follow‐up. Patients in treatment group 2 received non‐surgical periodontal treatment and supragingival prophylaxis at the 3‐month follow‐up, and those in the control group received no intervention throughout the study. All participants were reexamined at 1.5, 3, and 6 months after initial treatment. At each visit, clinical periodontal examinations were conducted and blood samples were taken to evaluate high‐sensitivity C‐reactive protein (hsCRP), tumor necrosis factor‐α (TNF‐α), glycated hemoglobin (HbA1c), fasting plasma glucose (FPG), and lipid profiles.Results: Both treatment groups had a significantly lower hsCRP level after periodontal therapy (P <0.05). Although HbA1c declined significantly in treatment group 2 (P <0.05), the intergroup difference for HbA1c, FPG, TNF‐α, and lipid profiles was not statistically significant after therapy (P >0.05).Conclusions: Non‐surgical periodontal treatment can effectively improve periodontal and circulating inflammatory status. Despite a lack of strong evidence, trends in some results support improved glycemic control after periodontal treatment in patients with diabetes.
Evidence‐Based Periodontal Plastic Surgery. II. An Individual Data Meta‐Analysis for Evaluating Factors in Achieving Complete Root Coverage
Authors: Chambrone Leandro , Pannuti Cláudio Mendes , Tu Yu‐Kang , Chambrone Luiz Armando 
Published: August 2011

Background: The aim of this review is to conduct an individual patient data meta‐analysis of randomized controlled clinical trials (RCTs) to evaluate whether baseline recession‐, patient‐, and procedure‐related factors can influence the achievement of complete root coverage (CRC).Methods: A literature search with no restrictions regarding status or the language of publication was performed for MEDLINE (for Medical Literature Analysis and Retrieval System Online), EMBASE (for Excerpta Medica Database), CENTRAL (for Cochrane Central Register of Controlled Trials), and the Cochrane Oral Health Group's Specialized Register databases up to and including March 2011. Only RCTs, with a duration of ≥6 months evaluating recession areas (Miller Class I or II) that were treated by means of root coverage procedures were included. Mixed‐effects logistic regression analyses were conducted to evaluate associations between five baseline variables and CRC.Results: Of the 70 potentially eligible trials, 22 were included in the meta‐analyses. In total, the data from 320 patients and 16 procedures were evaluated. None of the RCTs were classified as low risk of bias. Of the 602 recessions treated, 310 (51.5%) achieved CRC. Subepithelial connective tissue grafts (SCTGs), matrix grafts, and enamel matrix derivative protein (EMD) procedures were superior in achieving CRC when compared to coronally advanced flap (CAF) alone. For the adjusted covariates, the greater the baseline recession depth, the smaller the chance of achieving CRC (individual procedure analysis [odds ratio (OR) = 0.55; 95% confidence interval (CI) = 0.44, 0.70] and grouped procedure analysis [OR = 0.56; 95% CI = 0.45, 0.71]), as well as studies with conflict of interest were more likely to achieve CRC than those without conflict of interest (individual procedure analysis [OR = 6.78; 95% CI = 1.78, 25.86]).Conclusions: SCTGs, matrix grafts, and EMD were superior to CAF in achieving CRC, but SCTGs showed the best predictability. The impossibility of inclusion of all identified RCTs should be taken into consideration when interpreting the present findings.
The Association Between Neighborhood Characteristics and Body Size and Physical Activity in the California Teachers Study Cohort
Authors: Keegan Theresa H. M. , Hurley Susan , Goldberg Debbie , Nelson David O. , Reynolds Peggy , Bernstein Leslie , Horn-Ross Pam L. , Gomez Scarlett L. 
Published: August 2011

Objectives. We considered interactions between physical activity and body mass index (BMI) and neighborhood factors. Methods. We used recursive partitioning to identify predictors of low recreational physical activity (< 2.5 hours/week) and overweight and obesity (BMI ≥ 25.0 kg/m2) among 118 315 women in the California Teachers Study. Neighborhood characteristics were based on 2000 US Census data and Reference US business listings. Results. Low physical activity and being overweight or obese were associated with individual sociodemographic characteristics, including race/ethnicity and age. Among White women aged 36 to 75 years, living in neighborhoods with more household crowding was associated with a higher probability of low physical activity (54% vs 45% to 51%). In less crowded neighborhoods where more people worked outside the home, the existence of fewer neighborhood amenities was associated with a higher probability of low physical activity (51% vs 46%). Among non–African American middle-aged women, living in neighborhoods with a lower socioeconomic status was associated with a higher probability of being overweight or obese (46% to 59% vs 38% in high–socioeconomic status neighborhoods). Conclusions. Associations between physical activity, overweight and obesity, and the built environment varied by sociodemographic characteristics in this educated population.
Reinforcement of Smoking and Drinking: Tobacco Marketing Strategies Linked With Alcohol in the United States
Authors: Jiang Nan , Ling Pamela M. 
Published: August 2011

Objectives. We investigated tobacco companies’ knowledge about concurrent use of tobacco and alcohol, their marketing strategies linking cigarettes with alcohol, and the benefits tobacco companies sought from these marketing activities. Methods. We performed systematic searches on previously secret tobacco industry documents, and we summarized the themes and contexts of relevant search results. Results. Tobacco company research confirmed the association between tobacco use and alcohol use. Tobacco companies explored promotional strategies linking cigarettes and alcohol, such as jointly sponsoring special events with alcohol companies to lower the cost of sponsorships, increase consumer appeal, reinforce brand identity, and generate increased cigarette sales. They also pursued promotions that tied cigarette sales to alcohol purchases, and cigarette promotional events frequently featured alcohol discounts or encouraged alcohol use. Conclusions. Tobacco companies’ numerous marketing strategies linking cigarettes with alcohol may have reinforced the use of both substances. Because using tobacco and alcohol together makes it harder to quit smoking, policies prohibiting tobacco sales and promotion in establishments where alcohol is served and sold might mitigate this effect. Smoking cessation programs should address the effect that alcohol consumption has on tobacco use.