U-Th vs. AMS 14C dating of shells from the Achenheim loess (Rhine Graben)

2005 ◽  
Vol 176 (3) ◽  
pp. 249-255 ◽  
Author(s):  
Christophe Innocent ◽  
Christine Flehoc ◽  
Francis Lemeille
Keyword(s):  
14C Dating ◽  
Average Value ◽  
Rhine Graben ◽  
Younger Age ◽  
Isochron Diagram ◽  
Dating Method ◽  
Thorium 232 ◽  
Ams 14C Dating ◽  
Good Agreement

Abstract Shells extracted from loess deposits at Achenheim (Rhine Graben) have been investigated for AMS 14C and for U-Th dating by the isochron method on single shells. The two chronometers provide results that are not in agreement : the obtained 14C date is 38 ka B.P. In contrast, U-Th results provide much older ages. The 238U/232Th –230Th/232Th isochron diagram gives an age of 69 kyr, whereas a slightly younger age of 64 kyr is derived from the other, 234U/232Th – 230Th/232Th, diagram. 234U/238U ratios have not been found to vary from a shell to another : the average value is 1.199, slightly higher than radioactive equilibrium. For both isochrons, the Y-axis intercept is slightly negative, which indicates that there is no evidence for a significant detrital component. Thorium 232 that is present in the shells is probably incorporated in the material. The negative intercepts suggest that the two ages have been probably “aged” resulting from a slight mobilisation of uranium. By constraining the Y-axis intercepts at 0, ages that are in good agreement from one to another, can be calculated at 60.9 kyr and 60.4 kyr, respectively. In both cases, the statistical quality of the alignment is only slightly deteriorated. Since U-Th ages are in agreement with stratigraphic data, in contrast to the 14C date, one may believe that they date the end of early diagenesis, with uranium trapping. In contrast, the AMS 14C date is either thought to reflect analytical limitations of AMS 14C dating for such type of material, or to date a younger geologic event. In this latter case, a possible hypothesis is that this event has triggered the slight opening of the 238U – 234U system. In any case, this study demonstrates once again that surface formations often tell such complex stories that only one single dating method cannot usually be sufficient to describe precisely these histories. Instead, informations derived from different independent chronometers have to be compared.

PENENTUAN SIFAT KEKUKUHAN DAN KETEBALAN LAPISAN PERMUKAAN BERASFALT MENGGUNAKAN KAEDAH PENCARIAN RESONAN TAMBAHAN (ERS)

2015 ◽  
Vol 76 (1) ◽  
Author(s):  
Nur Mustakiza Zakaria ◽  
Muhammad Fakhry Md. Jaffary ◽  
Muhammad Kamal Hassan ◽  
Asmah Hamim ◽  
Nur Izzi Md. Yusoff ◽  
...  
Keyword(s):  
Elastic Moduli ◽  
Public Works ◽  
Traffic Load ◽  
Average Value ◽  
Resonance Search ◽  
Materials Used ◽  
Pavement Construction ◽  
Pavement Thickness ◽  
Good Agreement

This study was conducted to investigate the stiffness and thicknesses of asphalt surface layer using the Enhance Resonance Search (ERS) technique. A total of fifteen locations in the Universiti Kebangsaan Malaysia (UKM) Campus have been identified to carry out this experiment. The results were then compared with standards provided by the Malaysian Public Works Department (PWD), Jabatan Pembangunan dan Penyelenggaraan (JPP) UKM and Kumpulan IKRAM Sdn. Bhd. The computation found that the range of elastic moduli values of asphalt layer is between 3928.877 and 17726.012 MPa. A comparison between the experiment results and JPP UKM standard on pavement thickness showed that the different is between 20% to 60%, with the average thickness of 44.13 mm.  However, the average value of thickness is still in good agreement with the JKR and JPP UKM standards. Some stiffness values obtained are higher than the standard, probably due to the quality of materials used, the influence of the traffic load and the age of the pavement construction.

scholarly journals AMS 14C Dating of the Cremated Human Bones and Funeral Fuel of the Western Balts. In Theory and in Practice

2019 ◽  
Vol 20 ◽  
pp. 40-74
Author(s):  
Roman Shiroukhov
Keyword(s):  
Static Analysis ◽  
Radiocarbon Dating ◽  
Baltic Region ◽  
14C Dating ◽  
Human Bones ◽  
Dating Method ◽  
Ams 14C Dating

The article is dedicated to the application of AMS 14C dating method of cremated bones and samples of related charcoal, which is rather new for the East Baltic region. The data of 3 Western Balts cemeteries from Lithuania are analysed. Results of radiocarbon dating are compared to the estimated typological chronology of the artefacts. The OxCal simulation is applied in order to obtain the most probable dates. The study lays the foundation for further spatial and static analysis of selected data.

scholarly journals Preparation of Graphite Targets in the Gliwice Radiocarbon Laboratory for AMS 14C Dating

Radiocarbon ◽  
2001 ◽  
Vol 43 (2A) ◽  
pp. 283-291 ◽  
Author(s):  
Justyna Czernik ◽  
Tomasz Goslar
Keyword(s):  
Standard Samples ◽  
14C Dating ◽  
Ams Radiocarbon Dating ◽  
Free Quartz ◽  
Significant Contamination ◽  
To Come ◽  
Ams 14C Dating ◽  
Better Than ◽  
Quartz Tubes

A line for preparation of graphite targets for accelerator mass spectrometry (AMS) radiocarbon dating has been built in the Gliwice 14C Laboratory. The AMS 14C measurements of our targets are performed in the Leibniz-Labor für Altersbestimmung, Kiel, Germany. The quality of our line has been tested in two series of AMS 14C measurements of background and Ox-II standard samples and by measurements of the amount of CO2 released during combustion of sample-free quartz tubes. Most background contamination in the first series was introduced during combustion, which has been greatly reduced by baking quartz tubes vacuum-sealed with CuO and Ag. The residual contamination (ca. 1.5 μg C) seems to come mostly from the quartz tubes themselves. At present, most of the contamination of the background is introduced during graphitization. The reproducibility of background preparations is satisfactory, especially for samples larger than 1.5 mg, when it is better than ± 0.09 pMC. Despite still significant contamination with low-14C carbon during the graphitization process (corresponding to 1.2 ± 0.2% of 14C-free carbon), the good reproducibility of the results allows us to use our line in routine 14C dating.

scholarly journals High-Resolution AMS 14C Dating of Post-Bomb Peat Archives of Atmospheric Pollutants

Radiocarbon ◽  
2001 ◽  
Vol 43 (2B) ◽  
pp. 495-515 ◽  
Author(s):  
Michael E Goodsite ◽  
Werner Rom ◽  
Jan Heinemeier ◽  
Todd Lange ◽  
Suat Ooi ◽  
...  
Keyword(s):  
High Resolution ◽  
Radiocarbon Dating ◽  
General Purpose ◽  
Atmospheric Pollutants ◽  
Published Data ◽  
14C Dating ◽  
Peat Deposits ◽  
Dating Method ◽  
Ams 14C Dating ◽  
Made In

Peat deposits in Greenland and Denmark were investigated to show that high-resolution dating of these archives of atmospheric deposition can be provided for the last 50 years by radiocarbon dating using the atmospheric bomb pulse. 14C was determined in macrofossils from sequential one cm slices using accelerator mass spectrometry (AMS). Values were calibrated with a general-purpose curve derived from annually averaged atmospheric 14CO2 values in the northernmost northern hemisphere (NNH, 30°–90°N). We present a thorough review of 14C bomb-pulse data from the NNH including our own measurements made in tree rings and seeds from Arizona as well as other previously published data. We show that our general-purpose calibration curve is valid for the whole NNH producing accurate dates within 1–2 years. In consequence, 14C AMS can precisely date individual points in recent peat deposits within the range of the bomb-pulse (from the mid-1950s on). Comparing the 14C AMS results with the customary dating method for recent peat profiles by 210Pb, we show that the use of 137Cs to validate and correct 210Pb dates proves to be more problematic than previously supposed.As a unique example of our technique, we show how this chronometer can be applied to identify temporal changes in Hg concentrations from Danish and Greenland peat cores.

Korelasi kreativitas dan motivasi kerja guru terhadap peningkatan mutu pembelajaran

2016 ◽  
Vol 1 (1) ◽  
pp. 51
Author(s):  
Muh Nashiruddin ◽  
Anharurrohman El Muhammadi
Keyword(s):  
Religious Education ◽  
Work Motivation ◽  
Sampling Technique ◽  
Islamic Education ◽  
Learning Improvement ◽  
Average Value ◽  
Teacher Creativity ◽  
Teacher Work ◽  
And Behavior

Penelitian ini bertujuan untuk mengetahui korelasi antara: 1) kreativitas guru PAI terhadap peningkatan mutu pembelajaran Pendidikan Agama dan Budi Pekerti , 2) motivasi kerja guru PAI terhadap peningkatan mutu pembelajaran Pendidikan Agama dan Budi Pekerti , dan 3) kreativitas dan motivasi kerja guru terhadap peningkatan mutu pembelajaran Pendidikan Agama dan Budi. Penelitian ini menggunakan metode deskripsi korelasional dengan melibatkan 33 orang sampel yang dipilih secara dengan metode sensus. Teknik pengumpulan data dilakukan dengan angket/kuesioner. Teknikanalisis data diawali dengan uji prasyarat yaitu uji normalitas dan linieritas. Uji hipotesis menggunakanuji regresi sederhana danuji regresi ganda. Hasil penelitian menunjukkan ; 1) Kreativitas guru berpengaruh terhadap peningkatan mutu pembelajaran Pendidikan Agama Islam dan Budi Pekerti. 2) motivasi kerja guru berpengaruh terhadap peningkatan mutu pembelajaran Pendidikan Agama Islam dan Budi Pekerti. 3) kreativitas guru dan motivasi kerja guru secara bersama-sama atau simultan berpengaruh terhadap mutu pembelajaran. Hasil analisis juga menunjukkan bahwa rata-rata nilai dari ketiga variabel tersebut hanya dapat dimasukkan dalam kategori sedang, sehingga untuk meningkatkan kinerja guru dalam mengajar perlu diperhatikan faktor-faktor lain seperti: gaji, jaminan kerja, jaminan hari tua, penghargaan atas prestasi kerja, dan sebagainya. Kata kunci: kreativitas, motivasi, mutupembelajaran Abstract [The Relationship Between Teachers’ Creativity and Motivation Toward Learning Improvement]. This research aim at determine the correlation between the creativity of teachers on the improvement of learning quality of religious education and behavior, the work motivation of teachers on the improvement of learning quality of religious education and behavior, and the creativity and the work motivation of eachers on the improvement of learning quality of religious education and behavior. This research employed a method of correlation description with 33 Islamic education teacher were selected as sample by means of census sampling. Technique of collecting data employed questionnaire. Technique of data analysis began with prerequisite of normality and linearity. Hypothesis used test of simple regression and double regression.The study revealed that teacher creativity affects on the improvement of learning quality of religious education and behavior, as well as teacher work motivation affects on the improvement of learning quality of religious education and behavior. Futhermore, analysis show that teacher creativity as well as teacher work motivation affects simultaneously on the learning quality of Islamic Education. In conclusion, the average value of those three variables may be only included into medium category. Thus, to increase teacher performance, it needs other factors, such as; salary, job guarantee, pension, appreciation of work achievement, etc. Keywords: Creativity, Motivation, Learning Quality

Associations of Age, Gender, and Family Income with Quality of Life in Children With Advanced Cancer

2021 ◽  
pp. 104345422199232
Author(s):  
Piera C. Robson ◽  
Mary S. Dietrich ◽  
Terrah Foster Akard
Keyword(s):  
Quality Of Life ◽  
Advanced Cancer ◽  
Family Income ◽  
Hematologic Malignancy ◽  
Secondary Analysis ◽  
Quality Of Life Inventory ◽  
Younger Age ◽  
Self Reports ◽  
Life Inventory

Background: Children with cancer often experience decreased quality of life (QOL) throughout the illness trajectory. The purpose of this study was to explore the associations of demographic characteristics with QOL in children with advanced cancer. Methods: This secondary analysis was part of a larger randomized clinical trial that evaluated the efficacy of a legacy intervention for children (7–17 years) with relapsed/refractory cancer and their primary parent caregivers. Assessments included child self-reports on the Pediatric Quality of Life Inventory (PedsQL) Cancer Module. Researchers used descriptive and linear regression statistical methods. Results: Children ( n = 128) averaged 10.9 years (SD = 3.0). The majority were female ( n = 68, 53%), white ( n = 107, 84%), had a hematologic malignancy ( n = 67, 52%), with family incomes of $50,000 or less ( n = 81, 63.3%). Statistically significant positive associations of both age and income level with PedsQL scores were observed ( p < .05) but not gender ( p > .05). The strongest correlations for age were with the procedural anxiety ( beta = 0.42), treatment anxiety ( beta = 0.26), and total ( beta = 0.28) scores (all p < .01). In general, there was a positive correlation between family income levels and PedsQL scores ( p < .05). The strongest correlations for income were with nausea ( R = 0.49), appearance ( R = 0.44), pain, and treatment anxiety (both R = 0.42) (all p < .01). Associations adjusted for age remained essentially the same (all p < .01). Discussion: Children with advanced cancer with lower family income and younger age are at high risk for poorer QOL. Oncology nurses should seek to identify families who may benefit from additional resources to promote QOL.

Features of relativistic charged particles produced in catastrophic destruction of heavy emulsion nuclei at 4.5 A GeV

1998 ◽  
Vol 76 (7) ◽  
pp. 559-566 ◽  
Author(s):  
P Singh ◽  
M S Khan ◽  
H Khushnood
Keyword(s):  
Poisson Distribution ◽  
Linear Dependence ◽  
Charged Particles ◽  
Average Multiplicity ◽  
Average Value ◽  
Multiplicity Distributions ◽  
Good Agreement ◽  
Fireball Model

Total disintegration events produced in 4.5 A GeV/c 12C--AgBr reactions are analysed to investigate the characteristics of secondary charged particles produced in such collisions. The results reveal that multiplicity distributions of grey, black, and relativistic charged particles agree with the Poisson distribution. The average multiplicity of grey particles is found to increase with the increasing mass of projectile, while the average value of black particles is found to decrease with the increasing mass of projectile. This result is in good agreement with the prediction of fireball model. Finally, the linear dependence of grey and compound multiplicities on black, heavy, and relativistic charged particles is also observed. PACS No.: 25.70

Technically Classified Rubber—The Non-Rubber Content and the Measurement of Cure Rate

1953 ◽  
Vol 26 (3) ◽  
pp. 655-673 ◽  
Author(s):  
A. G. Veith
Keyword(s):  
Preliminary Investigation ◽  
National Bureau ◽  
Cure Rate ◽  
Average Value ◽  
Astm Method ◽  
Viscosity Increase ◽  
Strain Testing ◽  
Time Test ◽  
Short Time ◽  
Good Agreement

Abstract The nonrubber content of typical samples of all grades of technically classified rubber has been determined. It is found that the nonrubber content increases in the order: red, yellow, and blue. The chemical analyses performed to determine the nonrubber content were as follows: per cent ash, per cent nitrogen, per cent acetone extract, and per cent fatty acid. The pH of both a slurry of the ash and the aqueous digest indicates that blue rubber is more basic in these respects than are red and yellow rubbers. The measurement of the cure rate of these samples of technically classified rubber has been carried out by means of (1) conventional stress-strain testing, (2) the present ASTM method utilizing the Mooney viscometer, (3) the National Bureau of Standards strain test, (4) a new and more quantitative approach developed by Gee and coworkers, and (5) a utilization of the Mooney viscometer to determine two of the parameters of Gee's equation which gives the time dependence of modulus. All of these methods place the rubbers in the same relative order. The use of the viscometer to determine two of the parameters of Gee's equation was prompted by the degree of correlation between the rate parameter obtained with the present ASTM method and the rate constant k calculated by Gee's methods. As a result of a preliminary investigation as to the causes of viscosity increases at curing temperatures, it was found that, within limits of experimental error, all of the viscosity increase is due to the formation of a cross-linked network, with a linear relationship existing between viscosity increase ΔVc and modulus (at 100 per cent elongation) f. The results of a comparison of the rate constants obtained by the viscometer and by Gee's method indicate that for MBT mixes at 260° F there is good agreement between the methods. Statistical analysis shows that the samples employed for this study are significantly different in their rate of cure. The variance, range, and mean of some of the parameters obtained with the viscometer over a 10-week period are also given. It is suggested that the Mooney viscometer be employed to classify natural rubber according to its cure rate. If this is done, it will be necessary to define the degree of accuracy desired. To determine accurately the cure rate, it is necessary that the viscometer be used in conjunction with a press cure for the estimation of the parameter f∞. If it is not feasible to carry out press cures, an average value for f∞ can be assumed, and then only a short time test with the viscometer is required.

scholarly journals Rates and risk factors for amputation in people with diabetes in Japan: a historical cohort study using a nationwide claims database

2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Masanori Kaneko ◽  
Kazuya Fujihara ◽  
Mayuko Yamada Harada ◽  
Taeko Osawa ◽  
Masahiko Yamamoto ◽  
...  
Keyword(s):  
Lower Limb ◽  
Cox Regression ◽  
Lower Limb Amputation ◽  
Limb Amputation ◽  
Historical Cohort ◽  
Cox Regression Analysis ◽  
Claims Database ◽  
Younger Age

Abstract Background The prevalence of diabetes is rising, and diabetes develops at a younger age in East Asia. Although lower limb amputation negatively affects quality of life and increases the risk of cardiovascular events, little is known about the rates and predictors of amputation among persons with diabetes from young adults to those in the “young-old” category (50–72 y). Methods We analyzed data from a nationwide claims database in Japan accumulated from 2008 to 2016 involving 17,288 people with diabetes aged 18–72 y (mean age 50.2 y, HbA1c 7.2%). Amputation occurrence was determined according to information from the claims database. Cox regression model identified variables related to lower limb amputation. Results The mean follow-up time was 5.3 years, during which time 16 amputations occurred (0.17/1000 person-years). Multivariate Cox regression analysis showed that age (hazard ratio [HR] 1.09 [95% confidence intervals] 1.02–1.16, p = 0.01) and HbA1c (HR 1.46 [1.17–1.81], p < 0.01) were independently associated with amputations. Compared with those aged < 60 years with HbA1c < 8.0%, the HR for amputation was 27.81 (6.54–118.23) in those aged ≥60 years and HbA1c ≥8.0%. Conclusions Age and HbA1c were associated with amputations among diabetic individuals, and the rates of amputation were significantly greater in those ≥60 years old and with HbA1c ≥8.0%.

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