Development of a New Method to Reduce Drying Shrinkage of Concrete by Applying Urea

Cracking of concrete caused by drying shrinkage adversely affects the durability of the structure. In the past research results, it is effective to add urea to concrete as a way to reduce drying shrinkage. However, in ready mixed concrete factory in Japan, adding various admixture materials to concrete will increase equipment costs and labor costs because of the increase in the number of input items, the management problem and putting problem when mixing. In this research, in consideration of the above problems, we attempted to develop a cheaper and simpler method to apply or infiltrate the urea solution on the surface of concrete after demoulding as a method to reduce drying shrinkage. As a result, it was possible to reduce drying shrinkage by spraying urea solution on the concrete surface. It was also found that when the amount of urea solution in the concrete is higher, the drying shrinkage is lesser. This is considered that the urea solution entering into the concrete crystallizes in the gaps in the process of drying, and the expansion pressure of the crystallizing resists the drying shrinkage. It can also be considered that the water holding ability of urea prevents excessive drying of concrete. Furthermore, in order to prevent elution of urea inside the concrete due to rainwater, Na2SO4 reacting with remaining unreacted chemical components of concrete was mixed to the solution. And it was confirmed that effect of using the mix solution of urea and Na2SO4 was not lost if exposed in the rain

A Case History of Raft Foundation Behavior for a Large-Scaled Building Complex

This paper describes the field observation of settlement of a raft foundation for a large scale building complex in Nagoya city in Japan. The complex consists of a 28 story hotel, a 15 story office building and a low-storied banquet hall in the middle all of which are supported on a single 80 m square basement on raft foundation. Since the load on the foundation is non-uniform, the differential settlement of the foundation was investigated analytically, taking into consideration the interaction between the ground and the raft. To confirm the validity of the design, measurements were conducted for about 2 years during the building construction. The results of the measurement are discussed below

Geological structure of an arsenic-contaminated aquifer at Sonargaon, Bangladesh

ArticleJOURNAL OF GEOLOGY. 116(3):288-302(2008)journal articl

On Exceptional Vertex Operator (Super) Algebras

We consider exceptional vertex operator algebras and vertex operator superalgebras with the property that particular Casimir vectors constructed from the primary vectors of lowest conformal weight are Virasoro descendents of the vacuum. We show that the genus one partition function and characters for simple ordinary modules must satisfy modular linear differential equations. We show the rationality of the central charge and module lowest weights, modularity of solutions, the dimension of each graded space is a rational function of the central charge and that the lowest weight primaries generate the algebra. We also discuss conditions on the reducibility of the lowest weight primary vectors as a module for the automorphism group. Finally we analyse solutions for exceptional vertex operator algebras with primary vectors of lowest weight up to 9 and for vertex operator superalgebras with primary vectors of lowest weight up to 17/2. Most solutions can be identified with simple ordinary modules for known algebras but there are also four conjectured algebras generated by weight two primaries and three conjectured extremal vertex operator algebras generated by primaries of weight 3, 4 and 6 respectively.Comment: 37 page

Phase III Trial of Everolimus in Metastatic Renal Cell Carcinoma: Subgroup Analysis of Japanese Patients from RECORD-1

Objective: To assess the efficacy and safety of everolimus in Japanese patients with metastatic renal cell carcinoma. Methods: A subgroup analysis of the pivotal Phase III, randomized, double-blind, placebocontrolled trial of everolimus 10 mg/day in patients with disease progression after treatment with sorafenib, sunitinib or both assessed outcomes in Japanese participants. Results were compared with those for the overall study population. Results: The final trial analysis included 24 Japanese patients (everolimus, n 15; placebo, n 9). Median progression-free survival in the Japanese subpopulation was 5.75 months (95% confidence interval, 4.90 months to not reached) with everolimus and 3.61 months (95 % confidence interval, 1.91–9.03 months) with placebo (hazard ratio, 0.19; 95 % confidence interval, 0.05–0.83). Median overall survival was not reached with everolimus and was 14.9 month

Validity of self-reported diagnoses of gynaecological and breast cancers in a prospective cohort study: the Japan Nurses' Health Study

Objectives To validate the self-reported diagnoses of gynaecological and breast cancers in a nationwide prospective cohort study of nursing professionals: the Japan Nurses’ Health Study (JNHS).Design and setting Retrospective analysis of the JNHS.Participants and measures Data were reviewed for 15 717 subjects. The mean age at baseline was 41.6±8.3 years (median: 41), and the mean follow-up period was 10.5±3.8 years (median: 12). Participants are regularly mailed a follow-up questionnaire once every 2 years. Respondents who self-reported a positive cancer diagnosis were sent an additional confirmation questionnaire and contacted the diagnosing facility to confirm the diagnosis based on medical records. A review panel of experts verified the disease status. Regular follow-up, confirmation questionnaires and expert review were validated for their positive predictive value (PPV) and negative predictive value (NPV).Results New incidences were verified in 37, 47, 26 and 300 cervical, endometrial, ovarian and breast cancer cases, respectively. The estimated incidence rates were 22.0, 25.4, 13.8 and 160.4 per 100 000 person-years. These were comparable with those of national data from regional cancer registries in Japan. For regular follow-up, the corresponding PPVs for cervical, endometrial, ovarian and breast cancer were 16.9%, 54.2%, 45.1% and 81.4%, and the NPVs were 100%, 99.9%, 99.9% and 99.9%, respectively. Adding the confirmation questionnaire improved the PPVs to 31.5%, 88.9%, 76.7% and 99.9%; the NPVs were uniformly 99.9%. Expert review yielded PPVs and NPVs that were all ~100%.Conclusions Gynaecological cancer cannot be accurately assessed by self-reporting alone. Additionally, the external validity of cancer incidence in this cohort was confirmed

Synthesis and reactivity of 4-oxo-5-trimethylsilanyl derived α-amino acids

A Lewis-acid promoted one-carbon homologation of an aspartic acid semialdehyde with trimethylsilyldiazomethane has led to the efficient synthesis of two silicon-containing α-amino acids. The use of trimethylaluminium or catalytic tin(II) chloride gave novel 4-oxo-5-trimethylsilanyl derived amino acids in yields of 71–88%. An investigation into the reactivity of these highly functional α-amino acids showed that selective cleavage of the C–Si bond could be achieved under mild basic conditions to give a protected derivative of the naturally occurring amino acid, 4-oxo-l-norvaline. Alternatively, Peterson olefination with aryl or alkyl aldehydes resulted in the formation of E-enone derived α-amino acids

The effect of maternal anthropometric characteristics and social factors on gestational age and birth weight in Sudanese newborn infants

<p>Abstract</p> <p>Background</p> <p>In Africa low birth weight (LBW) (<2500 g), is the strongest determinant of infant morbidity and mortality. The aim of this study was to quantify the effect of maternal anthropometry, education and socio-economic status on gestational age and birth weight.</p> <p>Methods</p> <p>In 1000 Sudanese mothers with singleton births, anthropometric measurements (weight, height, mid-arm circumference) and newborn birth weight were taken within 24 hours of delivery. Furthermore, maternal education and socio-economic status were recorded. The effect of these maternal variables on gestational age and birth weight was investigated by receiver operating characteristic (ROC) curves and by multivariate logistic regression analysis.</p> <p>Results</p> <p>Although maternal height was significantly correlated (p = 0.002) with gestational age, we did not find maternal characteristics of value in determining the risk for preterm birth. Birth order was the strongest determinant of birth weight compared to other maternal characteristics. The LBW rate of first born babies of 12.2% was nearly twice that of infants of multiparous mothers. Maternal age and all maternal anthropometric measurements were positively correlated (p < 0.001) with birth weight. A maternal height of <156 cm, a maternal weight of <66 kg, a maternal mid arm circumference of <27 cm and years of education of ≤ 8 years were found to increase the relative risk of LBW but this was statistically significant only in the case of maternal height. Maternal age and BMI had no statistically significant effect on determining the risk for LBW. The social class did not affect the birth weight, while the number of years of education was positively correlated with birth weight (p = 0.01). The LBW rate decreased from 9.2% for ≤ 8 years of education to 6.0% for >12 years of education.</p> <p>Conclusion</p> <p>Birth order and maternal height were found to be the most important maternal parameters which influences birth weight and the risk for LBW. The duration of maternal education and not social class was found to significantly affect the risk for LBW.</p