bluuebunny/crossref_metadata_2025 huggingface dataset:
Fruit quality assessment of watermelons grafted onto citron melon rootstock
Authors: Fredes Alejandro , Roselló Salvador , Beltrán Joaquim , Cebolla‐Cornejo Jaime , Pérez‐de‐Castro Ana , Gisbert Carmina , Picó María Belén
Published: July 2016

BACKGROUND

The grafting of watermelons (Citrullus lanatus) is a common technique that increases yield under stressful soil conditions. The most common rootstocks for watermelons are Cucurbita hybrids. However, they often have a negative impact on fruit quality. Exploiting novel Citrullus germplasm such as citron melon (Citrullus lanatus var. citroides) is an alternative to avoid these quality problems.

RESULTS

Citron melon has been validated as watermelon rootstock, comparing its effects on watermelon quality to those of Cucurbita hybrids. Larger fruits with thicker rinds were observed in fruits from plants grafted onto both citron and Cucurbita rootstocks. The citron melon had no significant effect on flesh sugars or acid profiles compared to non‐grafted watermelons, except for an increase in glucose and malic acid content, which also occurred in the Cucurbita rootstocks. The aroma profile of fruits produced on citron melon was similar to that of the non‐grafted and self‐grafted controls. The citron rootstock did not display the increased levels of (Z)‐6‐nonen‐1‐ol (a compound associated with pumpkin‐like odors) found in fruits produced with Cucurbita hybrids.

CONCLUSION

The low impact of citron melon rootstock on fruit quality, along with the enhanced resistance against nematodes, make the citron a promising alternative to Cucurbita rootstocks. © 2016 Society of Chemical Industry
Tumor heterogeneity measured on F‐18 fluorodeoxyglucose positron emission tomography/computed tomography combined with plasma Epstein‐Barr Virus load predicts prognosis in patients with primary nasopharyngeal carcinoma
Authors: Chan Sheng‐Chieh , Chang Kai‐Ping , Fang Yu‐Hua Dean , Tsang Ngan‐Ming , Ng Shu‐Hang , Hsu Cheng‐Lung , Liao Chun‐Ta , Yen Tzu‐Chen
Published: July 2016

Objectives/Hypothesis

Plasma Epstein‐Barr virus (EBV) DNA concentrations predict prognosis in patients with nasopharyngeal carcinoma (NPC). Recent evidence also indicates that intratumor heterogeneity on F‐18 fluorodeoxyglucose positron emission tomography (18F‐FDG PET) scans is predictive of treatment outcomes in different solid malignancies. Here, we sought to investigate the prognostic value of heterogeneity parameters in patients with primary NPC.

Study Design

Retrospective cohort study.

Methods

We examined 101 patients with primary NPC who underwent pretreatment 18F‐FDG PET/computed tomography. Circulating levels of EBV DNA were measured in all participants. The following PET heterogeneity parameters were collected: histogram‐based heterogeneity parameters, second‐order texture features (uniformity, contrast, entropy, homogeneity, dissimilarity, inverse difference moment), and higher‐order (coarseness, contrast, busyness, complexity, strength) texture features.

Results

The median follow‐up time was 5.14 years. Total lesion glycolysis (TLG), tumor heterogeneity measured by histogram‐based parameter skewness, and the majority of second‐order or higher‐order texture features were significantly associated with overall survival (OS) and/or recurrence‐free survival (RFS). In multivariate analysis, age (P =.005), EBV DNA load (P = .0002), and uniformity (P = .001) independently predicted OS. Only skewness retained the independent prognostic significance for RFS. Tumor stage, standardized uptake value, or TLG did not show an independent association with survival endpoints. The combination of uniformity, EBV DNA load, and age resulted in a more reliable prognostic stratification (P < .001).

Conclusions

Tumor heterogeneity is superior to traditional PET parameters for predicting outcomes in primary NPC. The combination of uniformity with EBV DNA load can improve prognostic stratification in this clinical entity.

Level of Evidence

4 Laryngoscope, 127:E22–E28, 2017
Synthesis and Gas Storage Application of Hierarchically Porous Materials
Authors: Lu Chunjing , Ben Teng , Qiu Shilun
Published: July 2016

Porous organic frameworks (POFs) have been synthesized by Yamamoto‐type Ullmann cross‐coupling reaction using tetrakis (4‐bromophenyl) methane (TBPM) and poly‐4‐bromostyrene (PBS) as monomers. Among these POFs, JUC‐Z13 synthesized solely from PBS is found to be microporous (1.27 nm) and SBET = 372 m2 g−1, and copolymerization with TBPM results in POFs with apparent surface areas up to 3137 m2 g−1 and pore size up to 1.41 nm. Interestingly, JUC‐Z14 and JUC‐Z15 show hierarchical porosity. Low pressure gas uptake experiments on activated JUC‐Z13‐JUC‐Z19 show enhanced gas storage capacities and isosteric heats of sorption (Qst) among porous materials.

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Improving the reproducibility of motor unit number index
Authors: Escorcio‐Bezerra Marcio Luiz , Oliveira Acary Souza Bulle , De Oliveira Braga Nadia Iandoli , Manzano Gilberto Mastrocola
Published: July 2016

Introduction: Reproducibility is an important aspect of any method intended to be a marker of disease progression. In this study we investigated approaches for improving motor unit number index (MUNIX) reproducibility. Methods: We used the intraclass correlation coefficient (ICC) and the coefficient of variation (CV) to study reproducibility in healthy subjects. We tested reproducibility between test and retest of a single MUNIX from 3 different muscles (S‐MUNIX) and also of the mean of a set of 3 measurements from these same muscles (M‐MUNIX). Results: M‐MUNIX was more reproducible than S‐MUNIX. The CV showed a greater improvement than the ICC in all 3 muscles. Conclusions: M‐MUNIX may be a valuable approach for following motor unit loss, because it is more replicable than MUNIX. This may be especially relevant in amyotrophic lateral sclerosis patients, in whom MUNIX variability is higher than in healthy individuals. Muscle Nerve, 2016 Muscle Nerve 55: 635–638, 2017
Anthropometric predictors of body fat in a large population of 9‐year‐old school‐aged children
Authors: Almeida Sílvia M , Furtado José M , Mascarenhas Paulo , Ferraz Maria E , Silva Luís R , Ferreira José C , Monteiro Mariana , Vilanova Manuel , Ferraz Fernando P
Published: July 2016

Objective

To develop and cross‐validate predictive models for percentage body fat (%BF) from anthropometric measurements [including BMI z‐score (zBMI) and calf circumference (CC)] excluding skinfold thickness.

Methods

A descriptive study was carried out in 3,084 pre‐pubertal children. Regression models and neural network were developed with %BF measured by Bioelectrical Impedance Analysis (BIA) as the dependent variables and age, sex and anthropometric measurements as independent predictors.

Results

All %BF grade predictive models presented a good global accuracy (≥91.3%) for obesity discrimination. Both overfat/obese and obese prediction models presented respectively good sensitivity (78.6% and 71.0%), specificity (98.0% and 99.2%) and reliability for positive or negative test results (≥82% and ≥96%). For boys, the order of parameters, by relative weight in the predictive model, was zBMI, height, waist‐circumference‐to‐height‐ratio (WHtR) squared variable (_Q), age, weight, CC_Q and hip circumference (HC)_Q (adjusted r2 = 0.847 and RMSE = 2.852); for girls it was zBMI, WHtR_Q, height, age, HC_Q and CC_Q (adjusted r2 = 0.872 and RMSE = 2.171).

Conclusion

%BF can be graded and predicted with relative accuracy from anthropometric measurements excluding skinfold thickness. Fitness and cross‐validation results showed that our multivariable regression model performed better in this population than did some previously published models.
Additive manufacturing of carbon nanotube‐photopolymer composite radar absorbing materials
Authors: Zhang Yuanyuan , Li Houmin , Yang Xi , Zhang Tao , Zhu Kaiqiang , Si Wei , Liu Zhenliang , Sun Houjun
Published: July 2016

Additive manufacturing (AM) including Stereolithography (SLA) and more recent 3D printing derivatives is an innovative manufacturing technology, where objects can be manufactured by accumulation of successive layers of materials. Such technology enables the fabrication of highly customized radar absorbing materials (RAM) and novel RAM structures. The microwave absorption, printability, complex electromagnetic parameters were measured, acrylic ester photopolymer with carbon nanotubes (CNTs) content ranging from 0.5% to 1.5% prepared with digital masking AM technology. Good dispersion and the content of CNTs have major influences on the successful preparation. The printability limit of multiwalled CNT is found to be 1.6%.The maximum absorption of 6 mm‐thick composites is measured to be −15.98 dB with 1.5% CNT content. The real part (
) of permittivity increases from 2.5 to 7 and the imaginary part (
) of permittivity increases from 0.2 to 1.0 with the increasing content of CNTs. Frequencies, thickness, uniformly distribution of CNT and CNT content are the main factors affecting the RAM properties. The calculated reflection loss, for 12 mm‐thick composites, are −7 dB, −26 dB, and −34 dB for 0.5%, 1%, and 1.5% of CNT contents, respectively, and the matching frequency shifts to lower frequencies with the increase of thickness or CNT content, which is in agreement with electromagetic theory and experiment results. POLYM. COMPOS., 39:E671–E676, 2018. © 2016 Society of Plastics Engineers
Experimental demonstration of high‐concentration photovoltaics on a parabolic trough using tracking secondary optics
Authors: Cooper Thomas , Ambrosetti Gianluca , Malnati Fabio , Pedretti Andrea , Steinfeld Aldo
Published: July 2016

A new approach to high‐concentration photovoltaics (HCPV) based on a parabolic trough primary concentrator is presented. The design diverges from the standard HCPV arrangement of a two‐axis tracking point‐focus concentrator, and rather employs a simpler parabolic trough primary concentrator to reduce cost. To break the 2D limit of concentration, and bring the system into the realm of HCPV, the system employs an array of rotating secondary concentrators is arranged along the focal line of the parabolic trough. The resulting line‐to‐point (LTP) focus geometry allows the system to achieve a geometric concentration of 590×, yet still maintains the advantages of having a linear trough primary concentrator, namely manufacturability, economy, and scalability. A full‐scale prototype of the system was constructed in Biasca, Switzerland. During on‐sun tests a flux concentration of 364 suns was measured at the exit of the secondary concentrator, the highest reported concentration for any parabolic‐trough‐based system. Moreover, the system reached a peak efficiency of 20.2%, the highest measured solar‐to‐DC efficiency for a parabolic trough‐based solar collector. Long‐term performance is estimated by means of a coupled optical‐electrical model validated vis‐à‐vis the experimental results. This work serves as an experimental proof‐of‐concept for high‐concentration trough‐based collectors, thereby opening new avenues for reducing the cost of HCPV systems. Copyright © 2016 John Wiley & Sons, Ltd.
Towards a Best Practice Approach in PBPK Modeling: Case Example of Developing a Unified Efavirenz Model Accounting for Induction of CYPs 3A4 and 2B6
Authors: Ke A , Barter Z , Rowland‐Yeo K , Almond L
Published: July 2016

In this study, we present efavirenz physiologically based pharmacokinetic (PBPK) model development as an example of our best practice approach that uses a stepwise approach to verify the different components of the model. First, a PBPK model for efavirenz incorporating in vitro and clinical pharmacokinetic (PK) data was developed to predict exposure following multiple dosing (600 mg q.d.). Alfentanil i.v. and p.o. drug‐drug interaction (DDI) studies were utilized to evaluate and refine the CYP3A4 induction component in the liver and gut. Next, independent DDI studies with substrates of CYP3A4 (maraviroc, atazanavir, and clarithromycin) and CYP2B6 (bupropion) verified the induction components of the model (area under the curve [AUC] ratios within 1.0–1.7‐fold of observed). Finally, the model was refined to incorporate the fractional contribution of enzymes, including CYP2B6, propagating autoinduction into the model (Racc 1.7 vs. 1.7 observed). This validated mechanistic model can now be applied in clinical pharmacology studies to prospectively assess both the victim and perpetrator DDI potential of efavirenz.
Antidepressant use and recurrent falls in the elderly
Authors: Lam Y. W. Francis
Published: July 2016

Psychotropic drugs, including antidepressants, are commonly prescribed in elderly patients, and data suggest their use is associated with falls and resultant hip fracture.1,2 Questions remain, however, as to whether the falls are directly related to the use of medication or to the underlying depressive condition, and the association between recurrent falls and antidepressant use has seldom been investigated. The following longitudinal study evaluated the risk of recurrent falls in elderly users of various antidepressants, with the study including individuals with a history of falls and/or fracture.
Estimands in clinical trials – broadening the perspective
Authors: Akacha Mouna , Bretz Frank , Ruberg Stephen
Published: July 2016

Defining the scientific questions of interest in a clinical trial is crucial to align its planning, design, conduct, analysis, and interpretation. However, practical experience shows that oftentimes specific choices in the statistical analysis blur the scientific question either in part or even completely, resulting in misalignment between trial objectives, conduct, analysis, and confusion in interpretation. The need for more clarity was highlighted by the Steering Committee of the International Council for Harmonization (ICH) in 2014, which endorsed a Concept Paper with the goal of developing a new regulatory guidance, suggested to be an addendum to ICH guideline E9. Triggered by these developments, we elaborate in this paper what the relevant questions in drug development are and how they fit with the current practice of intention‐to‐treat analyses. To this end, we consider the perspectives of patients, physicians, regulators, and payers. We argue that despite the different backgrounds and motivations of the various stakeholders, they all have similar interests in what the clinical trial estimands should be. Broadly, these can be classified into estimands addressing (a) lack of adherence to treatment due to different reasons and (b) efficacy and safety profiles when patients, in fact, are able to adhere to the treatment for its intended duration. We conclude that disentangling adherence to treatment and the efficacy and safety of treatment in patients that adhere leads to a transparent and clinical meaningful assessment of treatment risks and benefits. We touch upon statistical considerations and offer a discussion of additional implications. Copyright © 2016 John Wiley & Sons, Ltd.
Variability management of plugin‐based systems using feature models
Authors: Santos André L.
Published: July 2016

Plugin‐based systems are typically realized with resort to a component framework that offers an infrastructure for assembling plugin components, which can be composed to form system variants. Feature models have been proposed as an abstraction to manage software variability, where feature configurations describe variants of a software system. In this paper, we propose an automated approach to map the artifacts of plugin‐based component frameworks to feature models. We describe a methodology for structuring the architecture of a plugin‐based system, so that the variability space and variants are reflected in a feature model and its configurations. We materialized the proposed approach for the Eclipse Equinox component framework in a tool to visualize the variability of plugin‐based systems in feature diagrams, which can be used to generate system variants. We carried out an experiment where we developed a small plugin‐based product line on top of Equinox in the context of an advanced software development course. Copyright © 2016 John Wiley & Sons, Ltd.
Cooperative amplify‐and‐forward partial relay selection with outdated channel information in spectrum‐sharing systems
Authors: Moualeu Jules Merlin , Hamouda Walaa , Takawira Fambirai
Published: July 2016

Recently, cooperative relaying techniques have been integrated into spectrum‐sharing systems in an effort to yield higher spectral efficiency. Many investigations on such systems have assumed that the channel state information between the secondary transmitter and primary receiver used to calculate the maximum allowable transmit secondary user transmit power to limit the interference is known to be perfect. However, because of feedback delay from the primary receiver or the time‐varying properties of the channel, the channel information may be outdated, which is an important scenario to cognitive radio systems. In this paper, we investigate the impact of outdated channel state information for relay selection on the performance of partial relay selection with amplify and forward in underlay spectrum‐sharing systems. We begin by deriving a closed‐form expression for the outage probability of the secondary network in a Rayleigh fading channel along with peak received interference power constraint and maximum allowable secondary user transmit power. We also provide a closed‐form expression for the average bit‐error rate of the underlying system. Moreover, we present asymptotic expressions for both the outage probability and average bit‐error rate in the high signal‐to‐noise ratio regime that reveal practical insights on the achievable diversity gain. Finally, we confirm our results through comparisons with computer simulations. Copyright © 2016 John Wiley & Sons, Ltd.
Abrupt summer warming and changes in temperature extremes over Northeast Asia since the mid-1990s: Drivers and physical processes
Authors: Dong Buwen , Sutton Rowan T. , Chen Wei , Liu Xiaodong , Lu Riyu , Sun Ying
Published: July 2016

This study investigated the drivers and physical processes for the abrupt decadal summer surface warming and increases in hot temperature extremes that occurred over Northeast Asia in the mid-1990s. Observations indicate an abrupt increase in summer mean surface air temperature (SAT) over Northeast Asia since the mid-1990s. Accompanying this abrupt surface warming, significant changes in some temperature extremes, characterized by increases in summer mean daily maximum temperature (Tmax), daily minimum temperature (Tmin), annual hottest day temperature (TXx), and annual warmest night temperature (TNx) were observed. There were also increases in the frequency of summer days (SU) and tropical nights (TR). Atmospheric general circulation model experiments forced by changes in sea surface temperature (SST)/sea ice extent (SIE), anthropogenic greenhouse gas (GHG) concentrations, and anthropogenic aerosol (AA) forcing, relative to the period 1964–93, reproduced the general patterns of observed summer mean SAT changes and associated changes in temperature extremes, although the abrupt decrease in precipitation since the mid-1990s was not simulated. Additional model experiments with different forcings indicated that changes in SST/SIE explained 76% of the area-averaged summer mean surface warming signal over Northeast Asia, while the direct impact of changes in GHG and AA explained the remaining 24% of the surface warming signal. Analysis of physical processes indicated that the direct impact of the changes in AA (through aerosol–radiation and aerosol–cloud interactions), mainly related to the reduction of AA precursor emissions over Europe, played a dominant role in the increase in TXx and a similarly important role as SST/SIE changes in the increase in the frequency of SU over Northeast Asia via AA-induced coupled atmosphere–land surface and cloud feedbacks, rather than through a direct impact of AA changes on cloud condensation nuclei. The modelling results also imply that the abrupt summer surface warming and increases in hot temperature extremes over Northeast Asia since the mid-1990s will probably sustain in the next few decades as GHG concentrations continue to increase and AA precursor emissions over both North America and Europe continue to decrease.
Voltammetric Response and Determination of an Anti‐Inflammatory Drug at a Cationic Surfactant‐Modified Glassy Carbon Electrode
Authors: Nayak Deepti S. , Shetti Nagaraj P.
Published: July 2016

Electrochemical oxidation of thiosalicylic acid in the presence of cationic surfactant, cetyl trimethylammonium bromide (CTAB), at a glassy carbon electrode was investigated. The electrochemical response of a modified sensor towards thiosalicylic acid determination was studied by the means of cyclic voltammetry, linear sweep voltammetry and differential pulse voltammetry (DPV). The liquid phase oxidation of thiosalicylic acid in the presence of CTAB leads to a notable enhancement in the peak current and a lowering of the peak potential. The electrochemical process was observed to be adsorption‐controlled, irreversible and involves oxidation of one electron. Effects of anodic peak potential (Ep), anodic peak current (Ipa) and heterogeneous rate constant (k0) were calculated. The linear response was obtained in the range of 1.0 µM–1.0 mM with a detection limit of 113 nM.
Florida State University Radiocarbon Dates I
Authors: Stipp J. J. , Knauer G. A. , Goodell H. G.
Published: July 2016

Laboratory construction was begun in December 1964 and routine dating was in progress by late February 1965. The primary purpose of this facility is to assist in marine geological studies and the archaeological chronologies of the region. Dating is carried out by utilizing the techniques of liquid scintillation described by Noakes et al. (1965), wherein the carbon of the sample to be dated is converted to benzene and the natural radioactivity detected in a liquid scintillation spectrometer.
University of Pennsylvania Radiocarbon Dates IX
Authors: Stuckenrath Robert , Coe William R. , Ralph Elizabeth K.
Published: July 2016

This date list includes those series of samples completed in this laboratory as of November, 1965. The B.P. ages are based upon A.D. 1950, and are calculated with a half-life value of 5568 yr. Errors quoted are those derived from measurements of sample, background, and modern-age calibration, and do not include any half-life error. All samples were pretreated with 3N HCl, and some, where noted, received additional pretreatment with 2% NaOH for the removal of possible humic contaminants.
Hannover Radiocarbon Measurements V
Authors: Geyh M. A.
Published: July 2016

This date list contains a selection of C14 dates of geological samples obtained from March 1963 until July 1966. The preceding date lists (Hannover I, III, IV) give a description of preparation and measuring methods.
University of Rome Carbon-14 Dates V
Authors: Alessio M. , Bella F. , Bachechi F. , Cortesi C.
Published: July 2016

The list of age measurements given below was obtained from December 1965 to October 1966, Nearly all archaeologic samples dated come from Italian territory, a few from Europe, Asia, and Africa. Some of the series continue or complete measurements published in previous lists (Rome II, III and IV) and refer to important deposits whose material, the result of several excavation campaigns, has been submitted at different times to our laboratory. All geologic samples come from Italian territory.
Uppsala Radiocarbon Measurements VIII
Authors: Stenberg Allan , Olsson Ingrid U.
Published: July 2016

The following list covers the samples measured since autumn 1964, when Uppsala VI was written, to determine the increase of the C14/C12 ratio due to explosion of nuclear devices.
UCLA Radiocarbon Dates VI
Authors: Berger Rainer , Libby W. F.
Published: July 2016

The measurements reported have been carried out during 1966 in the Isotope Laboratory of the Institute of Geophysics and Planetary Physics as a continuation of the UCLA date lists I through V. Samples were analyzed as CO2-gas at one atm in a 7.5 L proportional counter with three energy channels. The all-solid-state unit is supplied with high voltage from a remarkably stable and interference-free battery source. Radiocarbon ages have been calculated on the basis of a 5568-yr half-life as was recommended by the Sixth International C14 and H3 Dating Conference, June 1965, in Pullman, Washington. The standard for the contemporary biosphere remains as 95% of the count rate of NBS oxalic acid for radiocarbon laboratories. Background determinations have been based on CO2 obtained from marble. The error listed is always at least a one-sigma statistical counting error. In critical cases C13/C12 isotope ratio measurements were made to correct the dates. All samples were subjected to accepted pretreatments differing in the individual cases to exclude contamination.
Instituto Venezolano de Investigaciones Cientificas Natural Radiocarbon Measurements VI
Authors: Tamers M. A.
Published: July 2016

The I.V.I.C. laboratory continues operation using liquid scintillation spectrometry with synthesized benzene. A plastic-glass counting vessel contains 3 ml benzene, 1 ml commercial toluene, and concentrations of 0.4% PPO and 0.01% POPOP as scintillators. Background is 6.9 cpm and activity of the modern standard, 95% of the activity of the NBS oxalic acid, is 21.4 cpm. In the age calculations, 5568 years is taken for the half-life of C14and quoted errors are one standard deviation arising from the random nature of the radioactive disintegration process. Uncertainties in the half-life are not included nor are variations in the deposition rate of stratospheric radiocarbon and dilution by industrial use of fossil fuels. A.D. 1950 is employed as the reference year in the B.P. (before present) notation of ages.
University of Tokyo Radiocarbon Measurements IV
Authors: Kobayashi Hiromi , Matsui Yasuko , Suzuki Hisashi
Published: July 2016

The C14 measurements reported here were made in this laboratory between January 1969 and July 1970. Details of our apparatus, sample preparation, and measuring procedure were described in R., 1968, v. 10, p. 144–148. A change has been made since January 1969: strontium carbonate is reduced to strontium carbide with a mixture of 60g of SrCO3 to 40g of Mg-powder (<200 mesh) instead of 60g of SrCO3 to 50g of Mg-powder (<50 mesh).
Isotopes' Radiocarbon Measurements IX
Authors: Buckley James , Willis Eric H.
Published: July 2016

The measurements presented in this date list were made in the Radiocarbon Dating Laboratory at Teledyne Isotopes during 1969–70. Samples were analyzed by techniques described in R., 1968, v. 10, p. 246. Methods and references to sample pretreatment are provided in R., 1970, v. 12, p. 87. Errors associated with the age determinations are calculated by combining standard deviations from oxalic acid standard, background, and actual sample data. Samples which approach modern or background are reported with at least 2σ limits. Counting time for calculation of errors of background and standard is the same as that used for the sample. The error associated with the De Vries effect and the uncertainty of the half-life are not included.
Institute of Geological Sciences Radiocarbon Dates IV
Authors: Welin E. , Engstrand L. , Vaczy S.
Published: July 2016

This date list was compiled by the Institute of Geological Sciences (U.K.) incorporating data supplied under contract by E. Welin, Radioactive Dating Laboratory, Stockholm. Unless otherwise stated, age figures are in C14 years before a.d. 1950. The half-life of C14 is taken as 5568 years and the error, based on counting statistics of sample, background, and modern, is given as one standard deviation. Correction for C13/C12 fractionation has not been made.
Institut Royal Du Patrimoine Artistique Radiocarbon Dates IV
Authors: Dauchot-Dehon M. , Heylen J.
Published: July 2016

This list includes the results of datings made during 1970–71. The methods of measurements are the same as described in R., 1971, v. 13, p. 29–31.
University of Pennsylvania Radiocarbon Dates XV
Authors: Lawn Barbara
Published: July 2016

This date list includes most of the archaeologic and geologic samples dated in this laboratory since publication of our last date list (R., v. 12, p. 577–589), as well as some samples which had previously been dated, but lacked the sample information necessary for publication. Known-age samples, completed in this time period, will be reported elsewhere. The b.p. ages are based upon a.d. 1950, and have been calculated with the half-life value of 5568 yr. All samples were counted at least twice for periods of not less than 1000 minutes each. Errors quoted for each sample are derived from the measurement of the sample, the background, and of several counts of our mid-19th century standard oak sample, but do not include the half-life error. All samples were pretreated with 3N HCl, and some, where noted, were given additional pretreatment with 2% NaOH for the removal of possible humic acid contaminants.
University of Rome Carbon-14 Dates XI
Authors: Alessio M. , Bella F. , Improta S. , Belluomini G. , Cortesi C. , Manelli G. L.
Published: July 2016

During the last few years, we have set up the benzene scintillation method in our laboratory. C14 activity measurements are now carried out with both liquid scintillation and CO2-proportional counters. Chemical apparatus for benzene synthesis and a liquid scintillation spectrometer for low-level counting were built and are described below.
Geological Survey of Finland Radiocarbon Measurements VI
Authors: Heikkinen Aulis , Koivisto Anna-Kristina , Aikaa Osmo
Published: July 2016

In September 1970, the laboratory moved into new premises on the ground floor of a new building. The measuring room is constructed of low radioactive limestone concrete and is lined with grounded copper plate. Air conditioning insures a working temperature of 20 ± 1°C and a relative humidity of 40%.
Belfast Radiocarbon Dates VII
Authors: Smith A G , Pearson G W , Pilcher J R
Published: July 2016

The dating equipment and operating conditions remain essentially as previously described. All samples are from Ireland unless specified.
University of Texas at Austin Radiocarbon Dates X
Authors: Valastro S , Davis E Mott , Varela Alejandra G
Published: July 2016

This list reports 14C measurements completed between August 1971 and November 1973. Other projects completed in that period will be reported later. Age calculations are based on 14C half-life of 5568 yr and modern standard of 95% NBS oxalic acid, supplemented by tree rings of pre-industrial wood from a log cut in the 1850's (Tx-540; R, 1970, v 12, p 249). Deviations reported are based on counting statistics of sample, background, and modern, and are ± 1σ, except when sample count approaches either modern or background, 2σ limits are reported. Unless noted, 12C/13C measurements were not made and results are not corrected for 13C fractionation. The laboratory uses liquid scintillation counting of benzene, with Li2C2 and vanadium-activated catalyst in preparation; chemical yields average 90%. Three counters are employed: a Packard Tri-Carb Model 3002, and 2 Beckman LS-230 spectrometers obtained through a grant from the National Science Foundation.
University of Pennsylvania Radiocarbon Dates XVIII
Authors: Lawn Barbara
Published: July 2016

This date list includes most of the archaeologic samples dated in this laboratory since publication of our last date list (R, 1974, v 16, p 219–237), as well as some samples dated previously, which lacked adequate sample information. The BP ages are based on AD 1950, and have been calculated with the half-life value of 5568 yr. All samples were counted at least twice for periods of not less than 1000 min each. Errors quoted for each sample are derived from the measurement of the sample, the background, and several counts of our mid-19th century Oak sample, but do not include the half-life error. All samples were pretreated with 3N HCl and some, where noted, were given additional pretreatment with 2% NaOH for the removal of possible humic acid contaminants.
University of Miami Radiocarbon Dates III
Authors: Eldridge K L , Stipp J J , Cohen S J
Published: July 2016

The following radiocarbon measurements made since our last date list (R, v 17, p 112–120), are a partial list of projects and samples released for publication by the submitters. The technique employed is liquid scintillation counting of wholly synthesized benzene as described by Noakes et al (1965) and discussed in R, v 16, p 402–408. Errors are reported as one standard deviation. No correction factors are applied.
Vienna Radium Institute Radiocarbon Dates VI
Authors: Felber Heinz
Published: July 2016

Measurements have continued with the same proportional counter system, pretreatment procedure, methane preparation and measurement, and calculation, as described previously (R, 1970, v 12, p 298–318). Uncertainties quoted are single standard deviations originating from standard, sample, background counting rates and half-life. No C13/C12 ratios were measured.
Dalhousie University Natural Radiocarbon Measurements I
Authors: Ogden J Gordon , Hart W C
Published: July 2016

The Dalhousie University Radiocarbon Dating Laboratory was established in 1972, utilizing equipment and procedures formerly in use at Ohio Wesleyan University, Delaware, Ohio. The laboratory is located on the third floor of the 8-story Life Sciences Center at Dalhousie University. Sample preparation includes leaching with dilute alkali and acid, followed by pyrolysis in a stream of N2 at 500°C. Operating procedures remain essentially the same, utilizing reduction of acid or combustion generated CO2 to the counting gas, methane, over Ruthenium catalyst at 500°C. The flow reactor formerly used has been replaced by an in-line static reactor. Following gas purification and one month product gas storage to permit decay of Radon, samples are counted at 50 to 152cm pressure in either of 2 500ml detectors, or a 2L detector.
Gliwice (Gdansk) Radiocarbon Dates III
Authors: Moscicki W , Zastawny A
Published: July 2016

The first natural 14C measurements in Poland were made, using CO2 + CS2 G M counter as early as 1953 (Mościcki, 1953), but continuous operation was not possible until 1971. Following Poznań Toruń (Mościcki, 1958; 1961) and Gdańsk (Mościcki and Zastawny, 1962a), where the first long series of 14C measurements were made (Mościcki et al, 1967), an actively operating radiocarbon dating laboratory was installed at Gliwice in 1971.
Glasgow University Radiocarbon Measurements VIII
Authors: Stenhouse M J , Baxter M S
Published: July 2016

The analytical facilities at Glasgow have been extended to include gas proportional (CO2 and CH4) and liquid scintillation (C6H6) counting laboratories. The results presented here were obtained during 1972-1974 using the CO2 gas counting system only. In brief, organic samples, after pretreatment as described in the text, are burned in a tube combustion unit and the evolved CO2 absorbed in KOH solution. BaCO3 is precipitated and acid-hydrolyzed in vacuo using H3PO4. Evolved CO2 is purified via adsorption/desorption on CaO and is stored prior to counting. The 2.6L proportional counter is surrounded by a gas-flow Geiger anticoincidence guard and 10cm thick Pb shielding to reduce background count rates to ca 4.9 cpm at 1 atm filling and barometric pressures. A barometric sensitivity in background of −0.01cpm/mbar is observed. Constant gas gain is ensured by monitoring the coincidence meson spectrum and normalizing the detector operating voltage. All sample activities are related to the NBS oxalic acid standard count rate which averages 14.71 cpm at 1 atm filling pressure and 15°C. Mass spectrometric assay of CO2 after counting is performed on a VG Micromass 602B instrument to a precision of 0.05% (±1σ). Since uncertainties quoted on all results represent 1σ counting errors alone, they are related to precision of measurement rather than accuracy. The bulk of data quoted here are connected with a long-term study of the medical aspects of artificial 14C from nuclear weapon tests. These results should therefore be assessed in conjunction with those pub previously (Harkness and Walton, 1972; Farmer et al, 1972).
Birmingham University Radiocarbon Dates X
Authors: Williams R E G , Johnson A S
Published: July 2016

The following list of dates contains the majority of measurements made during 1975, ie, since our last list (R, 1975, v 17, p 255-275).
University of Georgia Radiocarbon Dates V
Authors: Noakes John E , Brandau Betty Lee
Published: July 2016

The following list of dates is compiled from samples prepared and catalogued since publication of our last date list (R, 1975, v 17, p 99-111). The counting equipment and operating procedures are the same. Ages are quoted with a 1σ counting error which includes statistical variation of the sample count as well as for background and standard, using ad 1950 as the reference year and 95% NBS oxalic acid for 14C dating as the standard. The half-life value used is 5570 years.
Quebec Radiocarbon Measurements I
Authors: Samson C , Barrette L , Lasalle P , Fortier J
Published: July 2016

The present list reports 14C measurements made in our laboratory from December 1972 to December 1973.
Yale University Geology and Geophysics Radiocarbon Dates I
Authors: Nozaki Y , Turekian K K
Published: July 2016

A radiocarbon dating system has been established at the Department of Geology and Geophysics, Yale University. Liquid-scintillation counting of benzene described by Noakes et al (1965) and Polach and Stipp (1967) is used. The operation of the original Yale Radiocarbon Laboratory, based on counting CO2 gas, was suspended in 1969. The present facility is operated as part of the geochemical laboratories of the Department of Geology and Geophysics. The operation is small, geared to solving geochemical problems, through the use of radiocarbon as a dating tool and as a natural tracer in combination with other geochemical parameters. The facility will collaborate on significant archaeologic and geologic problems. However, it will not be a facility to which samples are submitted routinely. We believe that commercial facilities and other laboratories dedicated to such kinds of operation are better suited to handling such diversity and volume of samples.
Physical Research Laboratory Radiocarbon Date List II
Authors: Agrawal D P , Krishnamurthy R V , Kusumgar Sheela , Pant R K
Published: July 2016

Presented below are dates from some important archaeologic and Quaternary sites. For the first time, a large number of dates have been reported here on the eustatic changes on the Eastern Indian coast. All dates are based on τ1/2 — 5568 yr; to convert the radiocarbon dates for archaeological samples into ad/bc scale, 1950 has been used as base year as per resolution passed at the Ninth International Radiocarbon Conference, San Diego, 1976. The dates are not corrected for 13C fractionation.
Mineralogical Studies On Bone Apatite and Their Implications for Radiocarbon Dating
Authors: Hassan Afifa A , Termine John D , Haynes C Vance
Published: July 2016

Infrared (IR) spectrophotometry and X-ray diffraction (XRD) were conducted on modern and fossil bone material from archaeological sites in the U S to determine post-mortem changes in bone apatite and to evaluate the effect of these changes on radiocarbon dating. IR absorption bands, XRD peak-broadening parameters, and XRD unit cell measurements indicated that during fossilization, bone apatite, a mineral similar to dahllite, was partially or completely recrystallized to francolite. Post-mortem changes involved then removal of some of the endogenous crystal carbonate both at surfaces and at internal OH-sites and introduction of exogenous carbonate into internal crystal PO4sites. Increased fluorine content accompanied carbonate substitution.

Both the carbon isotopic composition and the amount of exogenous carbonate introduced into the apatite structure will affect the radiocarbon dating of bone apatite. Special sample pre-treatment may remove most of the substituted carbonate in some cases. Simulated experiments are suggested for a better understanding of the nature and mechanism of carbonate substitution in bone apatite for the removal of the exogenously substituted carbon and the improvement of radiocarbon dates.
An Improved Procedure for Wet Oxidation of the 14C Nbs Oxalic Acid Standard
Authors: Valastro S , Land L S , Varela A G
Published: July 2016

An improved procedure for wet combustion of 14C NBS oxalic acid standard has been devised which gives consistent high carbon yields and average δ13C values of —19.1‰. The principal cause of fractionation in earlier attempts to prepare CO2 by the wet oxidation method was the inexact nature of the end-point. The new procedure employs a chocolate-brown end-point by adding 5ml more of the sulfuric acid-potassium permanganate solution after the initial reddish brown end-point is reached. The sulfuric acid-potassium permanganate solution is added to the NBS oxalic acid in a steady drop-wise flow, heat is applied to the generating apparatus, and a cycling technique is utilized to collect the CO2.

Fifteen samples of the NBS oxalic acid were processed. The per cent carbon yields range from 98.8 to 100.9% with an average of 99.7% and an average δ13C of —19.12‰. The results obtained by this procedure are much more consistent than previous results obtained in several laboratories by direct combustion.
Dalhousie University Natural Radiocarbon Measurements II
Authors: Ogden J Gordon , Hart W C
Published: July 2016

The following list includes determinations completed since publication of our last date list (R, 1976, v 18, p 43-49). Sample preparation and counting configuration remains the same as for DAL-I. Age determinations are based on at least two counter fillings (except as noted for very small samples) for a total of 3000 minutes and are calculated from at least 5000 minutes modern and background counts updated weekly by alternating modern and background samples in the counters over weekends. Age calculations are based on the Libby half-life of 5568 y and includes 1 σ statistical uncertainties of sample, modern, and background activity. Reference age is ad 1950 and is determined from 95 oxalic acid activity or age-corrected 1850 wood.
Nancy Natural Radiocarbon Measurements IV
Authors: Richard P , Guillet B , Jaegy R , Coppens R
Published: July 2016

This list includes results of measurements made during 1973-1974 and 1975 in the Natural Radiocarbon Laboratory of the Centre de Recherches Radiogéologiques de Nancy (CRR).
University of Miami Radiocarbon Dates XII
Authors: Calvert M , Rudolph Kim , Stipp J J
Published: July 2016

The following radiocarbon dates are a partial list of samples measured since March 1977. The techniques used are the same as reported in R, v 16, p 402-408, and modified in R, v 18, p 210-220, with the following exception. A third liquid scintillation counter (Beckman LS-100) has been added and the shortened, low-K glass-counting vials have been replaced with teflon vials of Noakes (1975) design. Backgrounds on the counters were thus reduced from 9.1 cpm, 8.8 cpm and 4.9 cpm to 3.8 cpm, 3.5 cpm and 2.8 cpm, respectively, with an attendant small increase in efficiency.
Precise 14C Measurement By Liquid Scintillation Counting
Authors: Pearson Gordon W
Published: July 2016

Radiocarbon dating involves a comparison of the count rate of sample carbon with that of modern reference standard material. To calculate a date the ratio Z must be determined where
Rudjer Bošković Institute Radiocarbon Measurements V
Authors: Srdoč Dušan , Sliepčevic Adela , Obelic Bogomil , Horvatinčic Nada
Published: July 2016

The following list contains dates of samples measured since our previous list (R, 1977, v 19, p 465-475). As before, age calculations are based on the Libby half-life, 5570 ± 30 years, and reported in years before 1950. The modern standard is 0.95 of the activity of NBS oxalic acid. Solid sample pretreatment, combustion and counting technique are essentially the same as described in R, 1971, v 13, p 135-140. Groundwater samples were prepared following the procedure adopted by the IAEA (IAEA, 1977). Carbonates and hydrocarbonates from water samples were precipitated by adding saturated barium chloride solution while the alkalinity was adjusted to pH = 8 by adding carbonate-free saturated solution of sodium hydroxide. The precipitation was enhanced by adding iron salts and Praestol as coagulating medium. Carbon dioxide was evolved by acidification of the precipitate and converted to methane. Statistical processing of data has been computerized (Obelić and Planinić, 1975). Sample descriptions were prepared with collectors and submitters. The errors quoted correspond to 1σ variation of sample net counting rate and do not include the uncertainty in 14C half-life.
Glasgow University Radiocarbon Measurements IX
Authors: Campbell J A , Baxter M S
Published: July 2016

The following date list presents results obtained during 1975-1977. The facilities at Glasgow have been further developed and include a gas counting system utilizing CO2 as counting material and two liquid scintillation counting laboratories based on synthesis of benzene. The results presented here were obtained using the liquid scintillation system only. Sample pretreatment varied according to individual sample type, whether wood or charcoal. The majority of samples were of preserved wood. After manual removal of gross contamination, samples of wood were finely chopped and digested in boiling, 2M KOH solution. The dehumified wood was then separated by filtration, thoroughly washed with distilled water and dilute hydrochloric acid, and then bleached in a solution of NaClO2/HCl at 80°C for 48 hours. Pure, white wood cellulose was obtained by filtration and washed with a large volume of distilled water. The cellulose, typically 40% by weight of the original material, was then dried overnight in an oven at 80°C. Samples of charcoal were closely examined for non-contemporaneous contamination and then subjected to successive treatments with hot, dilute (1M) KOH and HCL, respectively. The remaining charcoal was then dried overnight at 80°C.
US Geological Survey, Reston, Virginia, Radiocarbon Dates XV: Mauna Loa and Kilauea Volcanoes, Hawaii
Authors: Kelley M L , Spiker E C , Lipman P W , Lockwood J P , Holcomb R T , Rubin M
Published: July 2016

Ninety-six new 14C dates are reported for carbonized roots and other plant material coll from beneath prehistoric lava flows and ash deposits from Mauna Loa (ML) and Kilauea volcanoes. Before 1976, only 10 flows from these volcanoes had been dated by radiocarbon methods. Collection of dateable material has been facilitated by an improved understanding of the conditions of charcoal formation and preservation beneath basaltic lavas (Lockwood & Lipman, 1979).
Lyon Natural Radiocarbon Measurements VIII
Authors: Evin J , Marien G , Pachiaudi C
Published: July 2016

This list includes most of the measurements made in 1977 and 1978 using the two Packard liquid scintillation spectrometers described in Lyon VII (R, 1978, v 20, p 19). The backgrounds of both spectrometers decreased by about 30% with new photomultipliers, giving 1.9 ± 0.1cpm and 2.4 ± 0.2 cpm, respectively, for 3ml C6H6(depending on counting vessels). Proportional detectors are only used for very small samples. Counting procedures are described in the text. Dilution ratios indicate the amount of sample versus the total quantity of C6H6or CO2introduced in the detectors. No change was made either in chemical treatment or in the calculation method (half-life: 5570 ± 0, one standard deviation, standard13C correction only for bones).
Temple University Radiocarbon Dates I
Authors: Eldridge Koneta
Published: July 2016

Temple's radiocarbon dating facility is housed in the Department of Geology on the Main Campus. The laboratory was established to support research in late Pleistocene and Holocene Geology, Archaeology, and Anthropology.