scholarly journals EFFECTS OF WELDING PARAMETERS, TIME INTERVAL AND PREHEATING ON RESIDUAL STRESS AND DISTORTION OF JOINING ST52 STIFFENER RING IN AN AISI 4130 TUBULAR SHELL

2020 ◽  
Vol 3 (1) ◽  
pp. 11-15
Author(s):  
Alireza M. Haghighi ◽  
Farhad S. Samani
Keyword(s):  
Residual Stress ◽  
Welding Current ◽  
Welding Parameters ◽  
Time Interval ◽  
Negative Effects ◽  
Short Term ◽  
Welding Line ◽  
Aisi 4130 ◽  
Comparison Of The Results

Stiffener rings and stringers are used commonly in offshore and aerospace structures. Welding the stiffener to the structure causes the appearance of residual stress and distortion that leads to short-term and long-term negative effects. Residual stress and distortion of welding have destructive effects such as deformation, brittle fracture, and fatigue of the welded structures. This paper aims to investigate the effects of preheating, time interval and welding parameters such as welding current and speed on residual stress and distortion of joining an ST52-3N (DIN 1.0570) T-shape stiffener ring to an AISI 4130 (DIN 1.7218) thin-walled tubular shell by eleven pairs of welding line in both sides of the ring by means of finite element method (FEM). Results in tangent (longitudinal), axial and radial directions have been compared and the best welding methods proposed. After the comparison of the results, simultaneous welding both sides of the ring with preheating presented as the best method with less distortion and residual stresses among the studied conditions. The correctness of the FEM confirmed by the validation of the results.

scholarly journals Time Interval to Biochemical Failure as a Surrogate End Point in Locally Advanced Prostate Cancer: Analysis of Randomized Trial NRG/RTOG 9202

2019 ◽  
Vol 37 (3) ◽  
pp. 213-221 ◽  
Author(s):  
James J. Dignam ◽  
Daniel A. Hamstra ◽  
Herbert Lepor ◽  
David Grignon ◽  
Harmar Brereton ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
Randomized Trial ◽  
Locally Advanced ◽  
Biochemical Failure ◽  
Mediating Effect ◽  
Time Interval ◽  
Short Term ◽  
End Points ◽  
End Point

Background In prostate cancer, end points that reliably portend prognosis and treatment benefit (surrogate end points) can accelerate therapy development. Although surrogate end point candidates have been evaluated in the context of radiotherapy and short-term androgen deprivation (AD), potential surrogates under long-term (24 month) AD, a proven therapy in high-risk localized disease, have not been investigated. Materials and Methods In the NRG/RTOG 9202 randomized trial (N = 1,520) of short-term AD (4 months) versus long-term AD (LTAD; 28 months), the time interval free of biochemical failure (IBF) was evaluated in relation to clinical end points of prostate cancer–specific survival (PCSS) and overall survival (OS). Survival modeling and landmark analysis methods were applied to evaluate LTAD benefit on IBF and clinical end points, association between IBF and clinical end points, and the mediating effect of IBF on LTAD clinical end point benefits. Results LTAD was superior to short-term AD for both biochemical failure (BF) and the clinical end points. Men remaining free of BF for 3 years had relative risk reductions of 39% for OS and 73% for PCSS. Accounting for 3-year IBF status reduced the LTAD OS benefit from 12% (hazard ratio [HR], 0.88; 95% CI, 0.79 to 0.98) to 6% (HR, 0.94; 95% CI, 0.83 to 1.07). For PCSS, the LTAD benefit was reduced from 30% (HR, 0.70; 95% CI, 0.52 to 0.82) to 6% (HR, 0.94; 95% CI, 0.72 to 1.22). Among men with BF, by 3 years, 50% of subsequent deaths were attributed to prostate cancer, compared with 19% among men free of BF through 3 years. Conclusion The IBF satisfied surrogacy criteria and identified the benefit of LTAD on disease-specific survival and OS. The IBF may serve as a valid end point in clinical trials and may also aid in risk monitoring after initial treatment.

Do researchers impact their study populations? Assessing the effect of field procedures in a long term population monitoring of sea kraits

2012 ◽  
Vol 33 (3-4) ◽  
pp. 365-372 ◽  
Author(s):  
Thomas Fauvel ◽  
François Brischoux ◽  
Marine Jeanne Briand ◽  
Xavier Bonnet
Keyword(s):  
Body Condition ◽  
New Caledonia ◽  
Stress Hormones ◽  
Population Level ◽  
Population Monitoring ◽  
Long Term Effects ◽  
Negative Effects ◽  
Short Term ◽  
Head Morphology

Long term population monitoring is essential to ecological studies; however, field procedures may disturb individuals. Assessing this topic is important in worldwide declining taxa such as reptiles. Previous studies focussed on animal welfare issues and examined short-term effects (e.g. increase of stress hormones due to handling). Long-term effects with possible consequences at the population level remain poorly investigated. In the present study, we evaluated the effects of widely used field procedures (e.g. handling, marking, forced regurgitation) both on short-term (hormonal stress response) and on long-term (changes in body condition, survival) scales in two intensively monitored populations of sea kraits (Laticauda spp.) in New Caledonia. Focusing on the most intensively monitored sites, from 2002 to 2012, we gathered approximately 11 200 captures/recaptures on 4500 individuals. Each snake was individually marked (scale clipping + branding) and subjected to various measurements (e.g. body size, head morphology, palpation). In addition, a subsample of more than 500 snakes was forced to regurgitate their prey for dietary analyses. Handling caused a significant stress hormonal response, however we found no detrimental long-term effect on body condition. Forced regurgitation did not cause any significant effect on both body condition one year later and survival. These results suggest that the strong short-term stress provoked by field procedures did not translate into negative effects on the population. Although similar analyses are required to test the validity of our conclusions in other species, our results suggest distinguishing welfare and population issues to evaluate the potential impact of population surveys.

Low Mortality of Larval Lampreys from Electrofishing, Suction-pumping, Anesthesia, and Handling

2017 ◽  
Vol 8 (2) ◽  
pp. 640-647 ◽  
Author(s):  
Jeffrey C. Jolley ◽  
Christina T. Uh ◽  
Gregory S. Silver ◽  
Timothy A. Whitesel
Keyword(s):  
Pacific Northwest ◽  
Control Group ◽  
Long Term Effects ◽  
Negative Effects ◽  
Short Term ◽  
Important Species ◽  
Pacific Lamprey ◽  
The Pacific ◽  
Delayed Mortality

Abstract Native lamprey populations are declining worldwide. In the Pacific Northwest focus on conservation and management of these ecologically and culturally important species has increased. Concern has emerged regarding the effects of sampling and handling of lamprey, with little to no attention given to the larval lifestage. We monitored the survival of larval Pacific Lamprey Entosphenus tridentatus and Lampetra spp. after backpack electrofishing, deepwater electrofishing and suction-pumping, anesthesia, and handling. We performed survival trials on wild-caught lamprey (n = 15 larvae in each trial) collected from the Clackamas River drainage in Oregon, USA, coupled with control group trials from lamprey sourced from a hatchery (n = 10 larvae). Short-term (96 h) survival was >98% with only one observed mortality. Delayed mortality (1 wk) was observed for four individuals that had fungus; two of those were positive for the bacteria Aeromonas hyrdrophila. We recorded blood hematocrit as a secondary measure of stress. The baseline, nonstressed larvae hematocrit levels did not differ from those of fish that had undergone stress through electrofishing, suction-pumping, and handling without anesthesia. Electrofishing, suction-pumping, and anesthesia showed no short-term negative effects on larval lamprey although potential long-term effects remain unstudied. These techniques appear to provide efficient and relatively safe methods for collecting and surveying larval lamprey.

Intraindividual variation of glycohemoglobin: implications for interpretation and analytical goals

1993 ◽  
Vol 39 (11) ◽  
pp. 2305-2308 ◽  
Author(s):  
G Phillipou ◽  
P J Phillips
Keyword(s):  
Weighted Average ◽  
Affinity Column ◽  
Time Interval ◽  
Short Term ◽  
Intraindividual Variation ◽  
Clinical Control ◽  
Significant Difference ◽  
Patients With Diabetes ◽  
Analytical Imprecision

Abstract Intraindividual variation (CVi) for glycohemoglobin (GHb) was estimated from serial measurements in patients with diabetes in either stable or variable clinical control. GHb determinations were performed by an affinity column procedure with an analytical imprecision of 4.9% (weighted average; GHb 8.2-14.7%). Within the groups of patients, both a short- (28-32 days) and long-term (approximately 85 days) sampling protocol was used. The derived CVi for each category was 4.2% (n = 16, stable, short-term), 7.1% (n = 23, stable, long-term), 5.1% (n = 13, variable, short-term), and 9.8% (n = 21, variable, long-term). The mean GHb within each category was similar (approximately 11%), and there was no statistically significant difference in GHb values between categories. The results establish that the CVi for GHb is affected by both clinical control and the sampling time interval. These findings have important implications for the estimation of significant differences between serial GHb measurements and the setting of appropriate analytical precision goals.

scholarly journals Prediction of Net Profit Growth of Pharmacy Companies on the Indonesian Stock Exchange

2019 ◽  
Author(s):  
Dhani Ichsanuddin Nur
Keyword(s):  
Stock Exchange ◽  
Funding Source ◽  
Negative Effects ◽  
Short Term ◽  
Applied Model ◽  
Positive Effects ◽  
Funding Sources ◽  
Net Profit ◽  
Auto Regressive

Background: The research purpose to analyzing impacts of funding source changes on pharmacy company profits that went public on Indonesian Stock Exchange, with analysis period of 2008 to 2013. Methods: The research applied analysis means in line with requirements of change variable measurements of funding sources in its interconnectedness with company profits; the applied model was Auto-regressive. Results: The research results indicated that changes of the last one-period short term debts had negative effects insignificantly on company profits, the last two-period short term debts had positive effects significantly on company profits, changes of the last one-period and two-period long term debts had negative effects insignificantly on company profits, equity changes of the last period had positive effects significantly on company profits, the last period profit changes had negative effects significantly on company profits. Conclusion: Last one-period short term, last one-period long term, last two-period long term debt changes, and last period profit have negative insignificant effect on company profit. Last two-period short term debt changes, last one-period equity changes, and last two-period equity changes have positive significant effect on company profit.

scholarly journals Magmatic sill formation during dike opening

Geology ◽  
2021 ◽  
Author(s):  
Zhonglan Liu ◽  
W. Roger Buck
Keyword(s):  
Viscoelastic Medium ◽  
Average Density ◽  
Spreading Center ◽  
Time Interval ◽  
Two Dimensional ◽  
Short Term ◽  
Magma Intrusion ◽  
Spreading Ridges ◽  
Plate Spreading

The origin of horizontal magma-filled sills is disputed, particularly for extensional settings where the opening of vertical dikes is the predicted mode of magma intrusion. We simulate long-term extension followed by short-term dike opening in a two-dimensional viscoelastic medium representing a plate spreading center. We show that dike opening in extensionally stressed lithosphere can reduce sublithospheric vertical stresses enough for sill opening given three conditions: (1) the Maxwell time of the asthenosphere is <5× the time interval between dike episodes; (2) the average density of the lithosphere is not much greater than the magma density; and (3) the depth of an axial valley is smaller than a few hundred meters. This mechanism explains the presence of sills along much of the axis of faster-spreading ridges and their absence along slower-spreading centers where thick dense lithosphere and/or sizeable axial valleys exist.

scholarly journals Pleasure junkies all around! Why it matters and why ‘the arts’ might be the answer: a biopsychological perspective

2017 ◽  
Vol 284 (1854) ◽  
pp. 20162837 ◽  
Author(s):  
Julia F. Christensen
Keyword(s):  
Prefrontal Cortex ◽  
Well Being ◽  
Anterior Cingulate ◽  
Neural Systems ◽  
Negative Effects ◽  
Choice Behaviour ◽  
Short Term ◽  
The Arts ◽  
Dorsolateral Prefrontal

Today's society is pleasure seeking. We expect to obtain pleasurable experiences fast and easily. We are used to hyper-palatable foods and drinks, and we can get pornography, games and gadgets whenever we want them. The problem: with this type of pleasure-maximizing choice behaviour we may be turning ourselves into mindless pleasure junkies, handing over our free will for the next dopamine shoot. Pleasure-only activities are fun. In excess, however, such activities might have negative effects on our biopsychological health: they provoke a change in the neural mechanisms underlying choice behaviour. Choice behaviour becomes biased towards short-term pleasure-maximizing goals, just as in the addicted brain (modulated by the amygdala, posterior ventromedial prefrontal cortex' (VMPFC), striatum, nucleus accumbens; ‘A-system’) and away from long-term prosperity and general well-being maximizing objectives (normally ensured by the insula, anterior VMPFC, hippocampus, dorsolateral prefrontal cortex (DLPFC), anterior cingulate cortex (ACC); ‘I-system‘). This paper outlines, first, what ‘pleasure’ is and what ‘pleasure-only’ activities are (e.g. social media engagement, hyper-palatable eating). Second, an account is given of the type of action that might aid to maintain the neural systems underlying choice behaviour balanced. Finally, it is proposed that engagement with the arts might be an activity with the potential to foster healthy choice behaviour—and not be just for pleasure. The evidence in this rather new field of research is still piecemeal and inconclusive. This review aims to motivate targeted research in this domain.

Taking advantage of time-averaging

Paleobiology ◽  
1999 ◽  
Vol 25 (2) ◽  
pp. 226-238 ◽  
Author(s):  
Thomas Olszewski
Keyword(s):  
Temporal Resolution ◽  
Full Range ◽  
Exponential Model ◽  
Published Data ◽  
Time Interval ◽  
Time Averaging ◽  
Short Term ◽  
Constant Rate ◽  
Rapid Destruction

AbstractOne of the major obstacles in dealing with any form of data derived from fossils is the effects of time-averaging, which are the result of mixing the remains of organisms that did not live contemporaneously. Although this process results in loss of temporal resolution, it also serves to filter out short-term variations. Temporal resolution of a collection depends not only on the range of fossil ages, but also on their frequency distribution. Previous studies of marine molluscs indicate that most shells in an accumulation are relatively young. Such a distribution of shell ages can be fit by an exponential curve (assuming both a constant probability of shell loss and a constant rate of shell addition), which implies that 90% of the shells were added during the last 50% of the time interval represented by the collection. That is to say, differences between two collections can be discerned even if they overlap 50% in time, because the proportion of shells with shared ages is only 10%. Applying the exponential model to previously published data suggests that long-term rates of destruction are controlled by how frequently shells from the taphonomically active zone are re-exposed to rapid destruction. To take advantage of the “noise-filtering” property of time-averaging, samples need to be large enough to catch the full range of environmental variation recorded by an accumulation. A simple probability formula indicates that samples of easily achievable size can give satisfactory time-averaged results depending on the level of confidence and sampling density defined by the researcher.

Election boycott in a hybrid regime: The case of 2020 parliamentary elections in Serbia

2021 ◽  
pp. 2336825X2110091
Author(s):  
Dejan Bursać ◽  
Dušan Vučićević
Keyword(s):  
Hybrid Regimes ◽  
Negative Effects ◽  
Short Term ◽  
Parliamentary Elections ◽  
Election Results ◽  
Hybrid Regime ◽  
Progressive Party ◽  
Ruling Party ◽  
Short Term Effects

The 2020 elections in Serbia were held on 21st of June, as the first elections in Europe since the outbreak of coronavirus pandemic. The pre-electoral period was marked by the announcement of boycott from opposition, followed by a number of attempts of ruling party to mitigate the potential negative effects. The decision of opposition to restrain from participation came as a response to the long-term accusations of heavily biased electoral and media conditions, which culminated in EU-mediated (but largely unsuccessful) roundtable talks in 2019. On a larger scale, the administration headed by the President Aleksandar Vučić is becoming increasingly authoritarian, with several indices now classifying Serbia as a hybrid regime. As expected, the elections brought a convincing victory to Vučić’s Serbian Progressive Party, which won 188 out of 250 seats. Despite the overwhelming triumph, government was formed more than four months later. This paper is contributing to the literature on actors’ strategies in hybrid regimes. Although only short-term effects of the boycott could be assessed, the 2020 elections in Serbia demonstrate that legitimacy of the regime cannot be endangered if the opposition is not supported by international actors, and moreover, that the election results have only strengthened the regime.

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