459 research outputs found
The sustained influence of prior experience induced by social observation on placebo and nocebo responses
Background: Social observation is one of the main ways to gain experience. Similar to first-person experience, observational experience affects the effectiveness of subsequent treatments. Yet, it is still undetermined whether the influence of social observation on placebo and nocebo effects to subsequent treatments remains even if related experience occurred a few days ago.</p
The Influence of Expectation on Nondeceptive Placebo and Nocebo Effects
Nondeceptive placebo has demonstrated its efficiency in clinical practice. Although the underlying mechanisms are still unclear, nondeceptive placebo effect and nondeceptive nocebo effect may be mediated by expectation. To examine the extent to which expectation influences these effects, the present study compared nondeceptive placebo and nocebo effects with different expectation levels. Seventy-two healthy female participants underwent a standard conditioning procedure to establish placebo and nocebo effects. Sequentially, participants were randomized to one of the four experimental groups-baseline (BL), no expectation intervention (NoEI), expectation increasing (EI), and expectation decreasing (ED) groups, to receive either no intervention or interventions through different verbal suggestions that modulated their expectation. Placebo and nocebo effects were established in all four groups after the conditioning phase. However, after disclosing the placebo and nocebo, the analgesic and the hyperalgesic effects only persisted in the EI group, when compared with the BL group. Our results provide evidence highlighting the critical role of increased expectation in nondeceptive placebo and nocebo effects. The finding suggests that open-label placebo or nocebo per se might be insufficient to induce strong analgesic or hyperalgesic response and sheds insights into administrating open-label placebo and avoiding open-label nocebo in clinical practice.</p
Learning Discriminative Representation via Metric Learning for Imbalanced Medical Image Classification
Data imbalance between common and rare diseases during model training often
causes intelligent diagnosis systems to have biased predictions towards common
diseases. The state-of-the-art approaches apply a two-stage learning framework
to alleviate the class-imbalance issue, where the first stage focuses on
training of a general feature extractor and the second stage focuses on
fine-tuning the classifier head for class rebalancing. However, existing
two-stage approaches do not consider the fine-grained property between
different diseases, often causing the first stage less effective for medical
image classification than for natural image classification tasks. In this
study, we propose embedding metric learning into the first stage of the
two-stage framework specially to help the feature extractor learn to extract
more discriminative feature representations. Extensive experiments mainly on
three medical image datasets show that the proposed approach consistently
outperforms existing onestage and two-stage approaches, suggesting that metric
learning can be used as an effective plug-in component in the two-stage
framework for fine-grained class-imbalanced image classification tasks
The effect of fluorogypsum on the properties of high-water filling materials
Filling mining is an important way to realize the green development of mines. High-water filling materials have been widely used because of their short setting time. In this material, 40% of the raw material is natural anhydrite, and the main component is anhydrous calcium sulfate (CaSO4). Fluorogypsum is an industrial solid waste produced in the production of hydrofluoric acid. Its main composition is type II CaSO4. In order to explore the influence of fluorogypsum (F1, lime content of 3%; F2, lime content of 5%) on the performance of high water filling materials, the influence of fluorogypsum content on the setting time and 1, 7 and 28 d compressive strength of high-water filling materials at different experimental water temperatures and water binder ratio of 3∶1 was studied. At the same time, the hydration mechanism was studied by XRD, SEM, and TG-DTA. The results show that the setting time of high-water filling material increases gradually with the increase of fluorogypsum content at different experimental water temperatures. With the increase of F1 content, the low content has little effect on the compressive strength of high-water filling materials at different ages. When its content is higher than 20%, the compressive strength of high-water filling materials at 1, 7, and 28 days decrease gradually; with the increase of F2 content, the compressive strength of the high water filling material increases gradually at 1, 7, and 28 d. At different ages, compared with the blank group, the F2 content is 80%, and the maximum growth rate of its compressive strength is 29.7%. Microscopic analysis shows that the hydration products of high-water filling materials mainly include AFt, Al (OH) 3 (gel), and CaSO4 · 2H2O. After hydration for 1 d, the hydration rate of the F2 group (80% of F2) is fast and the amount of AFt is the largest, while the hydration rate of the blank group is the smallest and the amount of AFt is the smallest; After 28 d of hydration, the amount of aft produced in the three groups was the same. At the same time, based on the hydration kinetics of high-water filling material, the influence of fluorogypsum on the hydration process of high-water filling material is analyzed. It is concluded that fluorogypsum can replace natural anhydrite in high-water filling material systems and be applied to high-water filling material systems
Ten-year changes in the prevalence of overweight, obesity and central obesity among the Chinese adults in urban Shanghai, 1998–2007 — comparison of two cross-sectional surveys
BACKGROUND: In China, obesity is expected to increase rapidly in both urban and rural areas. However, there have been no comprehensive reports on secular trends in obesity prevalence among Chinese adults in urban Shanghai, which is the largest city in southern China. METHODS: In 1998–2001 and again in 2007–2008, two independent population-based cross-sectional surveys were conducted in Shanghai to investigate the prevalence of metabolic disorders. These surveys obtained height, waist circumference (WC), and weight measurements for Chinese adults aged between 20 and 74 years who lived in urban communities. From the 1998–2001 survey, 4,894 participants (2,081 men and 2,813 women, mean age: 48.9 years) were recruited, and 4,395 participants (1,599 men and 2,796 women, mean age: 49.8 years) were recruited from the 2007–2008 survey. Using the World Health Organization criteria, overweight was defined as 25 kg/m(2) ≤ BMI < 30 kg/m(2) and obesity as BMI ≥ 30 kg/m(2). Central obesity was defined as WC ≥ 90 cm in men or ≥85 cm in women. The differences in prevalence of obesity, central obesity and overweight between the two surveys were tested using multivariable logistic regression analyses. RESULTS: Compared to the 1998–2001 survey, in the 2007–2008 survey the BMI distribution for men and the WC distribution for both genders is shifted significantly to the right along the x-axis (all p < 0.001). Over the ten years, the prevalence of combined overweight and obesity increased 24% (from 31.5% to 39.1%, p < 0.001) in men, but decreased 8% (from 27.3% to 25.0%; p < 0.01) in women. The prevalence of central obesity increased 40% in men (from 19.5% to 27.3%; p < 0.01), but the increase was not significant in women (15.0% to 17.1%; p = 0.051). In the total population, only central obesity showed a significant change between the populations in the two surveys, increasing 29% (from 17.3% to 22.4%; p < 0.001). CONCLUSIONS: Over this 10 year period, central obesity increased significantly in the Shanghai adult population. However, the prevalence of combined overweight and obesity was significantly increased in men but not in women
Serum electrolyte levels in relation to macrovascular complications in Chinese patients with diabetes mellitus
BACKGROUND: The prevalence of diabetes in China is increasing rapidly. However, scarce data are available on serum electrolyte levels in Chinese adults with diabetes, especially in those with cardiovascular complications. This study measured serum electrolyte levels and examined their relationship with macrovascular complications in Chinese adults with diabetes. METHODS: The three gender- and age-matched groups were enrolled into this analysis, which were 1,170 subjects with normal glucose regulation (NGR), 389 with impaired glucose regulation (IGR) and 343 with diabetes. Fasting plasma glucose (FPG), 2-hour post-load plasma glucose (2hPG), glycosylated hemoglobin A1c (HbA1c) and serum electrolyte levels were measured. Data collection included ankle brachial index results. RESULTS: Serum sodium and magnesium levels in the diabetes group were significantly decreased compared to the NGR group (sodium: 141.0 ± 2.4 vs. 142.1 ± 2.0 mmol/l; magnesium: 0.88 ± 0.08 vs. 0.91 ± 0.07 mmol/l, all P < 0.01), while the serum calcium level was significantly increased (2.36 ± 0.11 vs. 2.33 ± 0.09 mmol/l, P < 0.01). Multiple linear regression showed that serum sodium and magnesium levels in the diabetes group were negatively correlated with FPG, 2hPG and HbA1c (sodium: Std β = −0.35, -0.19, -0.25; magnesium: Std β = −0.29, -0.17, -0.34, all P < 0.01), while the serum calcium level was positively correlated with HbA1c (Std β = 0.17, P < 0.05). In diabetic subjects, serum sodium, magnesium and potassium levels were decreased in the subjects with the elevation of estimated glomerular filtration rates (P < 0.05). ANCOVA analysis suggested that serum magnesium level in subjects with diabetic macrovascular complications was significantly decreased compared with diabetic subjects without macrovascular complications after the effect of some possible confounding being removed (P < 0.05). CONCLUSIONS: Serum sodium and magnesium levels were decreased in Chinese subjects with diabetes, while the observed increase in calcium level correlated with increasing glucose level. Diabetic patients with macrovascular complications had lower serum magnesium level than those with no macrovascular complications
Pt nanoparticles decorated rose-like Bi2O2CO3 configurations for efficient photocatalytic removal of water organic pollutants
Pt nanoparticles decorated with rose-like Bi2O2CO3 configurations were synthesized via a simple photoreduction method at room temperature. The structure, morphology, optical and electronic properties, and photocatalytic performance of the as-prepared materials were characterized. Compared to pure Bi2O2CO3, the Pt/Bi2O2CO3 photocatalysts show better performance in decomposing RhB, BPA and OTC under visible light (? > 420 nm). The enhanced photocatalytic activity of Pt/Bi2O2CO3 could be attributed to the modification in light absorption (? > 420 nm) charge migration and the separation of photo-generated electrons (e?) and holes (h+). Free radical trapping experiments demonstrated that the main active species of the catalytic reaction are different in decomposing RhB and BPA.publishersversionPeer reviewe
The Influence of Expectancy Level and Personal Characteristics on Placebo Effects: Psychological Underpinnings
Placebo effects benefit a wide range of clinical practice, which can be profoundly influenced by expectancy level and personal characteristics. However, research on the issue of whether these factors independently or interdependently affect the placebo effects is still in its infancy. Here, we adopted a 3-day between-subject placebo analgesia paradigm (2-day conditioning and 1-day test) to investigate the influence of expectancy levels (i.e., No, Low, and High) and personal characteristics (i.e., gender, dispositional optimism, and anxiety state) on placebo effects in 120 healthy participants (60 females). Our results showed that the reduction of pain intensity in the test phase was influenced by the interaction between expectancy and gender, as mainly reflected by greater reductions of pain intensity in females at Low expectancy level than females at No/High expectancy levels, and greater reductions of pain intensity in males than in females at High expectancy level. Additionally, the reduction of pain unpleasantness was not only modulated by the interaction between expectancy and gender, but also by the interaction between expectancy and dispositional optimism, as well as the interaction between expectancy and anxiety state. Specifically, participants who were more optimistic in Low expectancy group, or those who were less anxious in High expectancy group showed greater reductions of pain unpleasantness. To sum up, we emphasized on regulating the expectancy level individually based on the assessment of personal characteristics to maximize placebo effects in clinical conditions
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