56 research outputs found
Decision ambiguity is mediated by a late positive potential originating from cingulate cortex
People often make decisions in the face of ambiguous information, but it remains unclear how ambiguity is represented in the brain. We used three types of ambiguous stimuli and combined EEG and fMRI to examine the neural representation of perceptual decisions under ambiguity. We identified a late positive potential, the LPP, which differentiated levels of ambiguity, and which was specifically associated with behavioral judgments about choices that were ambiguous, rather than passive perception of ambiguous stimuli. Mediation analyses together with two further control experiments confirmed that the LPP was generated only when decisions are made (not during mere perception of ambiguous stimuli), and only when those decisions involved choices on a dimension that is ambiguous. A further control experiment showed that a stronger LPP arose in the presence of ambiguous stimuli compared to when only unambiguous stimuli were present. Source modeling suggested that the LPP originated from multiple loci in cingulate cortex, a finding we further confirmed using fMRI and fMRI-guided ERP source prediction. Taken together, our findings argue for a role of an LPP originating from cingulate cortex in encoding decisions based on task-relevant perceptual ambiguity, a process that may in turn influence confidence judgment, response conflict, and error correction
Free Radical Damage in Ischemia-Reperfusion Injury: An Obstacle in Acute Ischemic Stroke after Revascularization Therapy
Acute ischemic stroke is a common cause of morbidity and mortality worldwide. Thrombolysis with recombinant tissue plasminogen activator and endovascular thrombectomy are the main revascularization therapies for acute ischemic stroke. However, ischemia-reperfusion injury after revascularization therapy can result in worsening outcomes. Among all possible pathological mechanisms of ischemia-reperfusion injury, free radical damage (mainly oxidative/nitrosative stress injury) has been found to play a key role in the process. Free radicals lead to protein dysfunction, DNA damage, and lipid peroxidation, resulting in cell death. Additionally, free radical damage has a strong connection with inducing hemorrhagic transformation and cerebral edema, which are the major complications of revascularization therapy, and mainly influencing neurological outcomes due to the disruption of the blood-brain barrier. In order to get a better clinical prognosis, more and more studies focus on the pharmaceutical and nonpharmaceutical neuroprotective therapies against free radical damage. This review discusses the pathological mechanisms of free radicals in ischemia-reperfusion injury and adjunctive neuroprotective therapies combined with revascularization therapy against free radical damage
Optimal cutoff of the triglyceride to highdensity lipoprotein cholesterol ratio to detect cardiovascular risk factors among Han adults in Xinjiang
Background: To determine whether TG/HDL-C ratio, which has been shown
to be an indicator of the metabolic syndrome (MetS) and insulin
resistance (IR), can predict cardiovascular risk factors in the Chinese
Han population in Xinjiang. Methods: The cardiovascular risk survey
(CRS) was conducted from October 2007 to March 2010. A total of 14,618
representative participants were selected using a four-stage stratified
sampling method. A total of 5757 Han participants were included in the
study. The present statistical analysis was restricted to the 5595 Han
subjects who had complete anthropometric data. The sensitivity,
specificity, and distance on the receiver operating characteristic
(ROC) curve in each TG/HDL level were calculated. The shortest distance
in the ROC curves was used to determine the optimal cutoff of the
TG/HDL-C ratio for detecting cardiovascular risk factors. Results: The
prevalence of hypertension, hypercholesterolemia, and
hypertriglyceridemia was higher with higher TG/HDL-C ratio for both men
and women. The TG/HDL-C ratio was positively associated with systolic
blood pressure, diastolic blood pressure, and serum concentrations of
total cholesterol. The optimal TG/HDL-C ratio cutoffs for predicting
hypertension, dyslipidemia, diabetes, and 652 of these risk
factors for Han adults in Xinjiang were 1.3, 1.3, 1.4, and 1.4 in men
and 0.9, 1.0, 1.0, and 1.1 in women, respectively. Conclusions: The
evaluation of TG/HDL-C ratio should be considered for one of
cardiovascular risk factor predictors among Han adults in Xinjiang
Non-Standard Errors
In statistics, samples are drawn from a population in a data-generating process (DGP). Standard errors measure the uncertainty in estimates of population parameters. In science, evidence is generated to test hypotheses in an evidence-generating process (EGP). We claim that EGP variation across researchers adds uncertainty: Non-standard errors (NSEs). We study NSEs by letting 164 teams test the same hypotheses on the same data. NSEs turn out to be sizable, but smaller for better reproducible or higher rated research. Adding peer-review stages reduces NSEs. We further find that this type of uncertainty is underestimated by participants
Decision ambiguity is mediated by a late positive potential originating from cingulate cortex
How do city-specific factors affect migrant integration in China? A study based on a hierarchical linear model of migrants and cities.
BackgroundPrevious studies indicate that migrant integration is associated with migrants' characteristics as well as restrictions and opportunities in receiving cities. However, the effect of receiving cities and the relationship between migrants and receiving cities have not been fully explored due to the lack of large samples from cities. The objective of this study is to examine the effects of receiving cities alone and their regulating role in the interaction with individual characteristics.MethodsCross-city data on 154,044 Chinese domestic migrants above 15 years old in 289 cities from the 2017 China Migrants Dynamic Survey are used. Migrant integration is assessed by a four-dimensional model proposed by Esser, which is slightly adjusted according to the characteristics of Chinese migrants. A hierarchical linear model is used to measure the proportion of effects of city factors in migrant integration as well as the effects when city factors are considered alone and in interaction with individual factors.ResultsThe individual-level and city-level factors are responsible for 69.81% and 30.19% of the effect on migrant integration, respectively. City political factors do not affect migrant integration directly, and cities with larger sizes and higher wages can directly and significantly improve integration, while higher housing prices will directly inhibit integration. From the cross-level interaction of city and individual, different social, economic and political factors at the city level have an indirect impact on migrant integration by inhibiting or strengthening the effect of individual-level factors on migrant integration.ConclusionThis study is one of the first to show the effect of cities and the relationship between receiving cities and migrants on migrant integration by keeping the national context constant. It is necessary to weaken the social and economic privileges associated with a city's administrative level and reduce the negative impact of cities' social and economic conditions by implementing city agglomeration, developing advantageous industries and optimizing the industrial structure. It is also essential to improve migrants' socioeconomic capital through social support, occupation training and contiguous education
SCC fracture location shifting affected by stress-controlled fatigue damage of NiCrMoV steel welded joints
The influence of stress-controlled fatigue (SCF) damage on the fracture location shifting of welded joints for NiCrMoV steels in the corrosive solution of 3.5wt.% NaCl is systematically investigated by electrochemical measurements, immersion tests, slow strain rate tensile (SSRT) tests, and fractural morphology observations in the present work. The results show that both the yield strength (YS) and the ultimate tensile strength (UTS) of welded joints are increased after the SCF tests. The susceptibility of stress corrosion cracking (SCC) and galvanic corrosion of the SCF damaged welded joints are higher than that of the as-received specimens. In addition, the fracture locations of welded joints after SSRT tests in the corrosive solution are shifted with the degree of SCF damage. Different degrees of fatigue damage are accumulated in the three zones of welded joints during the cyclic deformation, which could change the competitive relation of the most susceptive SCC zone between the fusion zone and the middle of WM
Analysis of the thermodynamic performance limits of the organic Rankine cycle in low and medium temperature heat source applications
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