An Investigation of the Automatic Relative Gravimeters

2013 ◽  
Vol 199 ◽  
pp. 261-266 ◽  
Author(s):  
Eimuntas Parseliunas ◽  
Petras Petroškevičius ◽  
Romuald Obuchovski ◽  
Rosita Birvydiene

The laboratory and field investigations of the several automatic gravimeters Scintrex CG_5 with a quartz elastic system used for the determining of gravity acceleration were performed. Research on characteristics of four gravimeters includes a five-year period. The data consists of gravimetric observations at a laboratory, on the gravimetric testline and at the points of the Lithuanian gravimetric network. The evaluation of the phenomena of the spring systems of the gravimeters was made. The stress on the estimation of the zero drift at a laboratory and field investigations was done. It was detected that zero drift does not exceed 500 μGal per day with a diapason of 200 μGal. The zero drifts per hour do not exceed 25 μGal, mostly they are under 10 μGal. According to the annual calibration results the character of the changes of the linear scale coefficients of the gravimeters were analysed too. The calibration base of 270 km length in Lithuania where the difference of the gravity acceleration of the end points is 201 mGal was used for investigations. The research showed that the biggest deviation from the unit of the linear scale coefficients does not exceed 0.013. It was noted, that the values of the linear scale coefficients of the gravimeters have a tendency to decrease. Also was noted, that the values of the linear scale coefficients have a tendency to decrease in the period between field works, and to increase - in the field works period. So the calibration of the gravimeters should be carried out before and after the field works. Based on measurements carried out during development of the Lithuanian gravimetric network, which consists of 686 gravimetric points, accuracy of gravity acceleration increments was assessed. The comparison of the observations results against the results, obtained by the LaCoste and Romberg gravimeters with metal elastic system, is presented too. The total number of common points is 51. It was stated, that the differences of the gravity accelerations measured by the different types of gravimeters at gravimetric points do not differ more than 10 μGal, therefore maximum difference of 25 μGal was received. The standard deviations of the gravity accelerations of the gravimetric points do not exceed 7 μGal. Such results show the good performance of the SCINTREX CG_5 gravimeters.

2012 ◽  
Vol 13 (6) ◽  
pp. 867-872 ◽  
Author(s):  
Sudhir Kumar ◽  
P Ratnakar ◽  
NV Murali Krishna Chakka ◽  
Sanjib Das ◽  
Anandamy Bagchi ◽  
...  

ABSTRACT Aims Visual and microscopic evaluation of defects caused by torsional fatigue in hand and rotary nickel titanium (NiTi) instruments. Materials and methods Ninety-six NiTi greater taper instruments which were routinely used for root canal treatment only in anterior teeth were selected for the study. The files taken include ProTaper for hand use, ProTaper Rotary files and Endowave rotary files. After every use, the files were observed visually and microscopically (Stereomicroscope at 10×) to evaluate the defects caused by torsional fatigue. Scoring was given according to a new classification formulated which gives an indication of the severity of the defect or damage. Statistical analysis Data was statistically analyzed using KruskallWallis and Mann-Whitney U test. Results Number of files showing defects were more under stereomicroscope than visual examination. But, the difference in the evaluation methods was not statistically significant. The different types of defects observed were bent instrument, straightening/stretching of twist contour and partial reverse twisting. Endowave files showed maximum number of defects followed by ProTaper for hand use and least in ProTaper Rotary. Conclusion Visible defects due to torsional fatigue do occur in NiTi instruments after clinical use. Both visual and microscopic examinations were efficient in detecting defects caused due to torsional fatigue. This study emphasizes that all files should be observed for any visible defects before and after every instrumentation cycle to minimize the risk of instrument separation and failure of endodontic therapy. How to cite this article Chakka NVMK, Ratnakar P, Das S, Bagchi A, Kumar S, Anumula L. Do NiTi Instruments show Defects before Separation? Defects caused by Torsional Fatigue in Hand and Rotary Nickel-Titanium (NiTi) Instruments which Lead to Failure during Clinical Use. J Contemp Dent Pract 2012;13(6):867-872.


Foods ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 1546
Author(s):  
Tomoko Hasegawa ◽  
Nobuyuki Sakai

In Japan, as in other countries, the externalization of food preparation is increasing. Japanese people are interested in the combination of food and tableware and they are concerned about transferring ready-made meals from plastic containers to natural tableware. This study aimed to examine the varying evaluations of meals due to differences in tableware. In this study, we investigated the effect of tableware on meal satisfaction, which is emphasized in Japanese culture. We studied the difference in the evaluation of ready-made meals (a rice ball, salad, croquette, and corn soup) before, during, and after a meal under two conditions: plastic tableware and natural wooden tableware. The results showed that there was no difference in the perceptual evaluation of taste and texture during the meal, except for the color of the salad and the temperature of the soup. On the other hand, meals served on natural wooden tableware were rated more positively than those served on plastic tableware before and after meals. These results suggest that, in Japan, the use of tableware, even for ready-made meals, increases the level of meal satisfaction. These findings have implications for both the providers and consumers of ready-made meals as well as the food industry.


1987 ◽  
Vol 62 (4) ◽  
pp. 1627-1634 ◽  
Author(s):  
J. H. Bittel

Several types of cold adaptation in men have been described in the literature (metabolic, insulative, hypothermic). The aim of this study is to show that the decrease of heat debt can be considered as a new index for cold adaptation. Ten male subjects were acclimated by water immersions (temperature 10–15 degrees C, 4 immersions/wk over 2 mo). Thermoregulatory responses before and after acclimation were tested by a standard cold test in a climatic chamber for 2 h at rest [dry bulb temperature (Tdb): 10 degrees C; relative humidity (rh): 25%]. After adaptation, four thermoregulatory modifications were observed: an increase in the delay for the onset of shivering (32.7 +/- 7.99 instead of 14.1 +/- 5.25 min); a decrease of body temperature levels for the onset of shivering [rectal temperature (Tre): 37.06 +/- 0.08 instead of 37.31 +/- 0.06 degrees C; mean skin temperature (Tsk): 24.83 +/- 0.56 instead of 26.86 +/- 0.46 degrees C; mean body temperature (Tb): 33.03 +/- 0.20 instead of 34.16 +/- 0.37 degrees C); a lower level of body temperatures in thermoneutrality (Tre = 37.16 +/- 0.08 instead of 37.39 +/- 0.06 degrees C; Tsk = 31.29 +/- 0.21 instead of 32.01 +/- 0.22 degrees C; Tb = 35.92 +/- 0.08 instead of 36.22 +/- 0.05 degrees C); a decrease of heat debt calculated from the difference between heat gains and heat losses (5.66 +/- 0.08 instead of 8.33 +/- 0.38 kJ/kg). The different types of cold adaptation observed are related to the physical characteristics of the subjects (percent body fat content) and the level of physical fitness (VO2max).(ABSTRACT TRUNCATED AT 250 WORDS)


2006 ◽  
Vol 7 (4) ◽  
pp. 17-28 ◽  
Author(s):  
Ayman Ellakwa ◽  
Khalid Al-Abidi

Abstract Aim Gypsum products are used for the preparation of stone casts of oral and maxillofacial structures and as important adjuncts to dental laboratory operations involved in the production of dental prostheses. The aim of this study was to determine the effect on the dimensional accuracy of a working cast of adding a stone base using different stone products. Methods and Materials A total of forty impressions of a mandibular dentoform were made. The impressions were dried with compressed air and stored at room temperature for 24 hours before pouring stone casts. The forty impressions were randomly divided into four groups of ten each. All forty impressions were poured once using one pre-weighed 140 Gm package of Silky Rock (SR) Type IV improved stone (Whip Mix Corporation, Louisville, KY, USA) per impression. All working casts and the die setups were prepared according to the manufacturer's recommendations for pin placement (M.R. Dual pin and sleeve). Four different types of dental stone (II, III, and IV) and Flow Stone (FS) were used as bases for the working models. They were mixed according to the manufacturer's recommendations. The lower posterior teeth were flattened on the dentoform prior to taking the impressions. All were indexed using a mounted abrasive disc. Four teeth were selected as follows: 21, 28, 30, and 18. These represented A, B, C, and D landmarks, respectively. All measurements (five times for each specimen) were made with a Universal measuring microscope (Unitron Instruments, Inc., Bohemia, NY, USA). After the pre-sectioned measurements were recorded, the stone base was poured. A manual hand saw was used to section and fabricate removable dies for the mandibular landmarks A, B, C, and D. The dies were later seated and removed ten times to simulate the average amount of handling during laboratory procedures. Each die was carefully seated and measurements were made using the same technique as for the master model and unsectioned casts. Multivariate repeated measures analysis of variance (MANOVA) was used to test the difference in three different landmark distances (AB, AC, and AD) among the master model before and after sectioning of the working dies and among the four different base materials. Univariate analysis of variance (ANOVA) was conducted for each measurement, AB, AC, and AD to test the difference in landmark distances on the master model at pre sectioning and then at post sectioning using four different base materials. When there was a significant main effect (p < .05), the Student-Newman-Keul's (SNK) were used to test for pair wise comparison of means (P<0.05). Results The results of the MANOVA indicated there was a significant difference in three landmark measurements on the master model before and after sectioning of the working dies for the four different base materials (F=6.60, p=0.0001). In addition there was a significant difference in three landmark measurements on the master model at: (1) pre sectioning (p=0.0001), (2) between the master model and SR material (p=0.0002), (3) between the master model and Laboratory Plaster (LP) material (p=0.0001), (4) between the master model and Quick Stone (QS) material (p=0.0001), and (5) between the master model and FS material (p=0.0001). Citation Al-Abidi K, Ellakwa A. The Effect of Adding a Stone Base on the Accuracy of Working Casts Using Different Types of Dental Stone. J Contemp Dent Pract 2006 September;(7)4:017-028.


Author(s):  
R.A. Herring

Rapid thermal annealing (RTA) of ion-implanted Si is important for device fabrication. The defect structures of 2.5, 4.0, and 6.0 MeV As-implanted silicon irradiated to fluences of 2E14, 4E14, and 6E14, respectively, have been analyzed by electron diffraction both before and after RTA at 1100°C for 10 seconds. At such high fluences and energies the implanted As ions change the Si from crystalline to amorphous. Three distinct amorphous regions emerge due to the three implantation energies used (Fig. 1). The amorphous regions are separated from each other by crystalline Si (marked L1, L2, and L3 in Fig. 1) which contains a high concentration of small defect clusters. The small defect clusters were similar to what had been determined earlier as being amorphous zones since their contrast was principally of the structure-factor type that arises due to the difference in extinction distance between the matrix and damage regions.


1979 ◽  
Vol 42 (04) ◽  
pp. 1332-1339 ◽  
Author(s):  
Hiroh Yamazaki ◽  
Takeshi Motomiya ◽  
Minoru Sonoda ◽  
Noboru Miyagawa

SummaryChanges in platelets in 48 patients with uterine myoma before and after hysterectomy with and without ovariectomy were examined. Bilateral ovariectomy in 25 cases (ovariec-tomized group) and unilateral or non-ovariectomy in 23 cases (control group) were performed at the hysterectomy. Platelet count and an appearance rate of secondary aggregation decreased at one day after and increased at one week after the operation, similarly in both the ovariectomized and the control group. The appearance rate of secondary aggregation was reflected in an intensity of aggregation at 5 min after the addition of reagent to PRP. At one month after the operation, the appearance rate of secondary aggregation induced by 3 μM ADP showed a statistically significant decrease in comparison with the preoperation value (P <0.05) and the enhancement of 5-min aggregation was still observed in the control group, while ceased in the ovariectomized group. The difference between the two groups was significant (P < 0.05). There was almost no change in the speed and intensity of primary and secondary aggregation during the observation period. No significant differences in collagen-induced aggregation were noted between the two groups. The results suggest that ovarian hormones, mainly estrogen, facilitate platelet activation which is mediated by the so-called secondary aggregation.


Author(s):  
Niken Setyaningrum ◽  
Andri Setyorini ◽  
Fachruddin Tri Fitrianta

ABSTRACTBackground: Hypertension is one of the most common diseases, because this disease is suffered byboth men and women, as well as adults and young people. Treatment of hypertension does not onlyrely on medications from the doctor or regulate diet alone, but it is also important to make our bodyalways relaxed. Laughter can help to control blood pressure by reducing endocrine stress andcreating a relaxed condition to deal with relaxation.Objective: The general objective of the study was to determine the effect of laughter therapy ondecreasing elderly blood pressure in UPT Panti Wredha Budhi Dharma Yogyakarta.Methods: The design used in this study is a pre-experimental design study with one group pre-posttestresearch design where there is no control group (comparison). The population in this study wereelderly aged over> 60 years at 55 UPT Panti Wredha Budhi Dharma Yogyakarta. The method oftaking in this study uses total sampling. The sample in this study were 55 elderly. Data analysis wasused to determine the difference in blood pressure before and after laughing therapy with a ratio datascale that was using Pairs T-TestResult: There is an effect of laughing therapy on blood pressure in the elderly at UPT Panti WredhaBudhi Dharma Yogyakarta marked with a significant value of 0.000 (P <0.05)


2020 ◽  
Vol 22 (3) ◽  
pp. 341-361
Author(s):  
Gonzalo Grau-Pérez ◽  
J. Guillermo Milán

In Uruguay, Lacanian ideas arrived in the 1960s, into a context of Kleinian hegemony. Adopting a discursive approach, this study researched the initial reception of these ideas and its effects on clinical practices. We gathered a corpus of discursive data from clinical cases and theoretical-doctrinal articles (from the 1960s, 1970s and 1980s). In order to examine the effects of Lacanian ideas, we analysed the difference in the way of interpreting the clinical material before and after Lacan's reception. The results of this research illuminate some epistemological problems of psychoanalysis, especially the relationship between theory and clinical practice.


1962 ◽  
Vol 41 (1) ◽  
pp. 123-128 ◽  
Author(s):  
Pentti A. Järvinen ◽  
Sykkö Pesonen ◽  
Pirkko Väänänen

ABSTRACT The fractional determination of 17-ketosteroids in the daily urine was performed in nine cases of hyperemesis gravidarum and in four control cases, in the first trimester of pregnancy both before and after corticotrophin administration. The excretion of total 17-KS is similar in the two groups. Only in the hyperemesis group does the excretion of total 17-KS increase significantly after corticotrophin administration. The fractional determination reveals no difference between the two groups of patients with regard to the values of the fractions U (unidentified 17-KS), A (androsterone) and Rest (11-oxygenated 17-KS). The excretion of dehydroepiandrosterone is significantly higher in the hyperemesis group than in the control group. The excretion of androstanolone seems to be lower in the hyperemesis group than in the control group, but the difference is not statistically significant. The differences in the correlation between dehydroepiandrosterone and androstanolone in the two groups is significant. The high excretion of dehydroepiandrosterone and low excretion of androstanolone in cases of hyperemesis gravidarum is a sign of adrenal dysfunction.


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