limited effect
Recently Published Documents


TOTAL DOCUMENTS

627
(FIVE YEARS 207)

H-INDEX

37
(FIVE YEARS 5)

2022 ◽  
Author(s):  
Qianli Lu ◽  
Zhuang Liu ◽  
Jianchun Guo ◽  
Shouyi Wang ◽  
Le He ◽  
...  

Abstract Casing deformation (CD) is a major challenge for shale gas development in Weiyuan gasfield, natural fracture (NF) slippage is one of the main causes of CD in Weiyuan gas filed. In order to study the mechanism and regularity of NF slippage induced CD, a wellbore shear stress calculation model and a CD degree prediction model are established. And results show that, the approach angle and ground principal stress difference have significant influence on wellbore shear stress, high wellbore shear stress occurs when wellbore orientation is perpendicular to the NF trend. Wellbore shear stress increases with the increase of fracture fluid pressure and NF area, improving casing strength or cementing quality has limited effect on reducing the risk of CD. The smaller the young's modulus, the higher the CD degree, Poisson's ratio has limited effect on CD degree. NF approach and fracture fluid pressure determines the value of CD degree. Field case shows that reasonable fracturing technology to control fracture net pressure and wellbore position arrangement are helpful for reducing CD risk, and the model proposed in this paper can be used to predict CD risk and calculate the CD degree.


2022 ◽  
Vol 29 (1) ◽  
Author(s):  
Malte Storm ◽  
Florian Döring ◽  
Shashidhara Marathe ◽  
Silvia Cipiccia ◽  
Christian David ◽  
...  

Full-field transmission X-ray microscopy (TXM) is a very potent high-resolution X-ray imaging technique. However, it is challenging to achieve fast acquisitions because of the limited efficiency of the optics. Using a broader energy bandwidth, for example using a multilayer monochromator, directly increases the flux in the experiment. The advantage of more counts needs to be weighed against a deterioration in achievable resolution because focusing optics show chromatic aberrations. This study presents theoretical considerations of how much the resolution is affected by an increase in bandwidth as well as measurements at different energy bandwidths (ΔE/E = 0.013%, 0.27%, 0.63%) and the impact on achievable resolution. It is shown that using a multilayer monochromator instead of a classical silicon double-crystal monochromator can increase the flux by an order of magnitude with only a limited effect on the resolution.


Toxics ◽  
2022 ◽  
Vol 10 (1) ◽  
pp. 10
Author(s):  
Mojca Loncnar ◽  
Ana Mladenovič ◽  
Vesna Zalar Serjun ◽  
Marija Zupančič ◽  
Hans A. van der Sloot

Old metallurgical dumps across Europe represent a loss of valuable land and a potential threat to the environment, especially to groundwater (GW). The Javornik electric arc furnace (EAF) and ladle slag heap, situated in Slovenia, was investigated in this study. The environmental impact of the slag heap was evaluated by combining leaching characterization tests of landfill samples and geochemical modelling. It was shown that throughout the landfill the same minerals and sorptive phases control the leaching of elements of potential concern, despite variations in chemical composition. Although carbonation of the disposed steel slags occurred (molar ratio CO3/(Ca+Mg) = 0.53) relative to fresh slag, it had a limited effect on the leaching behaviour of elements of potential concern. The leaching from the slag heaps had also a limited effect on the quality of the GW. A site-specific case, however, was that leachates from the slag heap were strongly diluted, since a rapid flow of GW fed from the nearby Sava River was observed in the landfill area. The sampling and testing approach applied provides a basis for assessing the long-term impact of release and is a good starting point for evaluating future management options, including beneficial uses for this type of slag.


Nutrients ◽  
2021 ◽  
Vol 14 (1) ◽  
pp. 145
Author(s):  
Belal N. Alshaikh ◽  
Adriana Reyes Loredo ◽  
Megan Knauff ◽  
Sarfaraz Momin ◽  
Shirin Moossavi

Necrotizing enterocolitis (NEC) is a significant cause of mortality and morbidity in preterm infants. The pathogenesis of NEC is not completely understood; however, intestinal immaturity and excessive immunoreactivity of intestinal mucosa to intraluminal microbes and nutrients appear to have critical roles. Dietary fats are not only the main source of energy for preterm infants, but also exert potent effects on intestinal development, intestinal microbial colonization, immune function, and inflammatory response. Preterm infants have a relatively low capacity to digest and absorb triglyceride fat. Fat may thereby accumulate in the ileum and contribute to the development of NEC by inducing oxidative stress and inflammation. Some fat components, such as long-chain polyunsaturated fatty acids (LC-PUFAs), also exert immunomodulatory roles during the early postnatal period when the immune system is rapidly developing. LC-PUFAs may have the ability to modulate the inflammatory process of NEC, particularly when the balance between n3 and n6 LC-PUFAs derivatives is maintained. Supplementation with n3 LC-PUFAs alone may have limited effect on NEC prevention. In this review, we describe how various fatty acids play different roles in the pathogenesis of NEC in preterm infants.


2021 ◽  
pp. 109861112110538
Author(s):  
Silje Bringsrud Fekjær ◽  
Andreea Ioana Alecu

Recruiting police officers with immigrant backgrounds has a limited effect if many of these recruits leave the police service. The dropout and attrition rates among officers with immigrant backgrounds are also an important indicator of the challenges this group faces when joining the police profession. We investigated police education dropout patterns and attrition rates among police students and officers with immigrant backgrounds. Our study is based on detailed longitudinal data with total coverage of the population, which were previously unavailable for police career studies. Using logistic regression and coarsened exact matching, we analysed administrative registry data covering all individuals admitted to the Norwegian police university college (1995–2010, N = 6570) and all police-educated staff employed in the Norwegian police (1995–2014, N = 7001). Students and police officers with non-Western immigrant backgrounds have a greater tendency to both dropout of education and leave the police service. Prior academic performance can only partly explain these higher educational dropout rates. Female and males with non-Western immigrant backgrounds have similar dropout patterns. Our results provide a rationale for developing policy aimed at not only recruiting, but also retaining police officers with immigrant backgrounds.


Sociobiology ◽  
2021 ◽  
Vol 68 (4) ◽  
pp. e7286
Author(s):  
Adam Véle ◽  
Jovan Dobrosavljević

Red wood ants (the Formica rufa group) are important predators which affect animal communities in their territory. Therefore, they are useful in forest protection. On the other hand, they also prey on beneficial organisms. We have asked whether Formica rufa L. affects the abundance of the parasitic flies Ernestia rudis (Fallén). Ten anthills situated in about 40-year- old pine plantations were used for the study. The presence of E. rudis cocoons was assessed in eight soil samples excavated in the surrounding of each nest at a distance of 2–17 m. Our results show a considerably lower abundance of E. rudis only to 4.5 m from the nests. The occurrence of Formica rufa ants therefore had no significant effect on the beneficial E. rudis population in plantation forests, where ants populations are low.


2021 ◽  
Vol 24 (3-4) ◽  
pp. 428-466
Author(s):  
Noel M. Morada

Abstract This article examines how atrocity prevention efforts have had a limited effect on the violence and atrocities being committed in Myanmar. Myanmar’s military forces, the Tatmadaw, remain free to commit atrocities against vulnerable populations in the country, particularly against the Rohingya minority in Rakhine state. These efforts have been stymied at both the international and regional levels, especially now that the Tatmadaw rule the country following a coup d’etat in February 2021. UN efforts have fallen short as the Tatmadaw refuse to cooperate with the international community due to a lack of trust in UN processes and a subsequent siege mentality over heightened international outrage over the treatment of both the Rohingyas and protesters against the coup. Prevention efforts through asean, of which Myanmar is a member, have also fallen short. This is due primarily to a lack of accountability for erring members, and a long-standing principle of non-interference in members’ domestic affairs. Currently, there are no incentives for the Tatmadaw to negotiate and stop the violence committed against their own people. Indeed, the failure of these prevention efforts and the increased notions of nationalism they foster may be used by the Tatmadaw to continue their current policies of isolation and maintain power.


2021 ◽  
Vol 11 ◽  
Author(s):  
Suna Ye ◽  
Qiqi Fang ◽  
Jinyu Yao ◽  
Jianqiang Xing ◽  
Shibo Tang ◽  
...  

Angiographically silent cystoid macular edema (CME) is a rare complication from nab-paclitaxel. Here we report a 45-year-old woman with breast cancer who developed CME after several months of treatment with albumin-bound paclitaxel (nab-paclitaxel). Her visual acuity did not improve significantly with the cessation of nab-paclitaxel and intravitreal ranibizumab treatment. Then, brinzolamide eye drops were prescribed. One month later, her vision improved, with the macular edema significantly subsided. Finally, we reviewed other cases of CME induced by nab-paclitaxel that have been reported in the literature and discussed the underlying pathogenesis of nab-paclitaxel-induced CME.


Significance This marks the highest-ranking combat casualty suffered by the Nigerian army to date and is part of a series of recent ISWAP attacks as the group transitions into another fighting season following the end of the rainy season. Impacts The military will soon look to launch another major operation into ISWAP-held territory. Absent more robust and flexible ground capabilities, newly delivered A-29 Super Tucano aircraft will have limited effect against ISWAP. Humanitarian services will be confronted by increasing risks.


2021 ◽  
pp. 1-25
Author(s):  
Steffen Elstner ◽  
Svetlana Rujin

Abstract Since at least the mid-2000s, many advanced economies have experienced low productivity growth. This development is often related to declining productivity gains at the technology frontier, which is largely determined by the US. We challenge this explanation by studying the effects of US technology shocks on productivity levels in advanced economies. We find positive but small spillovers of US technology shocks. For many countries, the elasticity of their productivity with respect to a 1% increase in the US technology level is significantly lower than 1. Thus, the recent US productivity slowdown must have had a limited effect on productivity developments in advanced economies. Nevertheless, after 5 years, the degree of productivity spillovers varies across countries. Therefore, we analyze the role of institutions in shaping these results. Our findings suggest that isolated institutional characteristics are not able to explain the observed various spillover degrees.


Sign in / Sign up

Export Citation Format

Share Document