INFLUENCE OF DIFFERENT SOURCES AND LEVELS OF NITROGEN AND ROCK PHOSPHATE ADDITION ON MAIZE PRODUCTIVITY AND SOIL FERTILITY

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The Applications of Shape-Changing Rigid Body Mechanisms in Arts and Engineering

Design of shape-changing or shape-morphing machines is an area of growing importance. Shape-change can potentially be applied soon to vary the cross section of a wing, create wind or liquid flow control by morphing shapes to locally influence downstream fluid behavior, or vary the size of a car seat to meet a wider array of human anthropometric needs. Rigid body shape-change mechanisms offer many advantages including the high capacity to endure substantial loads while achieving large displacements. Their design techniques are also well-established. The goal of this research project is to develop the synthesis theory to address planar rigid-body shape-change where significant differences in arc length define the problem. A MATLAB-based software was developed to facilitate visual assessment of the process and results. Lastly, this paper illustrates several mechanization examples that apply the segmentation process, and the fundamental mechanism synthesis to guide the motion of the chain of rigid bodies to progress to the subsequent positions

Root Caries in an Optimally Fluoridated and a High-fluoride Community

The purpose of this study was to measure the prevalence and distribution of root caries in two New Mexico communities. One community, Deming, had a natural fluoride concentration of 0.7 mglL in its drinking water, optimum for its climate. The other, Lordsburg, was naturally fluoridated at 3.5 mg/L, five times the optimum. Dental examinations were carried out on 151 adults in Deming (mean age, 39.8 years) and 164 in Lordsburg (mean age, 43.2 years); only persons born in the communities were included. Prevalence of root caries was 23.8% in Deming and 7.3% in Lordsburg; mean number of lesions was 0.69 in Deming and 0.08 in Lordsburg (p < 0.0001). Although there was more gingival recession in Lordsburg, Root Caries Index scores were five times greater in Deming. Root caries was more prevalent in older age groups, and was correlated with coronal caries experience in both communities. Root caries was correlated with plaque and calculus scores in Deming only. Logistic regression showed that city of residence was the major predictor of root caries, with other significant predictors being age, education, gingival recession, and loss of periodontal attachment. When combined with previous research, these results confirm that root caries experience is directly related to the fluoride concentration in the drinking water.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/66733/2/10.1177_00220345860650090801.pd

PEMODELAN KEAUSAN PIN-ON-DISC DENGAN ANALISA ELEMEN HINGGA

Dunia engineering tidak bisa dilepaskan dari mekanisme perkontakan antara komponen mesin yang satu dengan yang lain. Berbagai masalah dapat timbul akibat kontak ini, diantaranya adalah keausan. Pemodelan keausan pin-on-disc  antara baja dengan baja  dimodelkan  dengan  analisa elemen hingga  (FEA). Kontak sliding disederhanakan menjadi model 2D dengan input sifat-sifat  material berbantuan software ANSYS. Hasil simulasi berupa tekanan kontak rata-rata digunakan untuk menghitung keausan Model Archard. Updating geometry dilakukan  untuk mengetahui besarnya keausan yang terjadi pada pin. Hasil pemodelan menunjukkan jari-jari kontak  dan keausan  mengalami peningkatan  sangat  signifikan  pada tahap awal, kemudian mencapai kestabilan  seiring dengan bertambahnya jarak sliding.  Kestabilan  tercapai  setelah menempuh jarak sliding 80405 mm. Fenomena kestabilan aus ini memperlihatkan bahwa sistem telah berada dalam fase steady state setelah melewati running-in dalam aplikasi pemesinan. Kata kunci:  keausan, pin-on-disc, upadating geometry, FE

Prevalence of Total Tooth Loss, Dental Caries, and Periodontal Disease in Mexican-American Adults: Results from the Southwestern HHANES

The Southwestern portion of the Hispanic Health and Nutrition Examination Survey (HHANES) was conducted by the National Center for Health Statistics (NCHS) in 1982 and 1983. The survey population was Mexican-Americans residing in five Southwestern states. This report presents data on the prevalence of total tooth loss, dental caries, and periodontal diseases in 3860 Mexican-American adults aged from 18 to 74. Results show that 4.3% of this group was edentulous. Among the dentate, Mexican-Americans had lower overall DMF scores but higher numbers of untreated decayed teeth than did residents of the same region seen in the NHANES I survey in 1971-1974. Caries of the smooth surfaces in both posterior and anterior teeth was more pronounced in the older than in the younger age groups. Mexican-Americans had more gingivitis but fewer periodontal pockets than did the general population in the Western states during NHANES 1. The caries pattern in the Mexican-Americans suggests that caries among adults may remain a problem in the future, with the possibility of increased involvement with the aging, although modest, of smooth tooth surfaces.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/68143/2/10.1177_00220345870660061801.pd

Effects of zinc oxide nanoparticles on viscosity of transesterified neem oil

Efforts have been made worldwide to find alternative fluids for industrial applications. Vegetable oil appears to be a perfect alternative, but using most of the vegetable oil as a feedstock made its use for industrial purposes challenging. The recent trend is to develop coolants/lubricants from non-edible seed oil. This work investigates the effects of zinc oxide nanoparticles on viscosity of transesterified neem oil. The crude neem oil was purified, transesterified and nanoparticles were dispersed in the transesterified oil at concentrations ranging from 0.0% to 1.0% at 0.2% intervals. Fourier Transform Infrared (FTIR) spectra were used to examine the structures of the samples and Scanning Electron Microscopy (SEM) analyses were used to examine the surface morphology of the samples. Viscosity were examined. Among other things, it was found that a small amount of ZnO (0.6%) nanoparticles in the oil could improve the viscosity of the fluid. The nanoliquid with a ZnO concentration of 0.6% appears to have optimal properties

Two new xanthones from Artocarpus obtusus

Two new xanthones, pyranocycloartobiloxanthone A (1) and dihydroartoindonesianin C (2), were isolated from the stem bark of Artocarpus obtusus Jarrett by chromatographic separation. Their structures were determined by using spectroscopic methods and comparison with known related compounds. Pyranocycloartobiloxanthone A (1) showed strong free radical scavenging activity by using DPPH assay as well as cytotoxicity towards K562, HL-60, and MCF7 cell lines