分类： 计算机科学 >> 计算机科学的集成理论 提交时间： 2024-12-03
摘要： Traditional recommendation systems focus on max#2;imizing user satisfaction by suggesting their favorite items. Thisuser-centric approach may lead to unfair exposure distributionamong the providers. On the contrary, a provider-centric designmight become unfair to the users. Therefore, this paper pro#2;poses a re-ranking model FairSort1to find a trade-off solutionamong user-side fairness, provider-side fairness, and personalizedrecommendations utility. Previous works habitually treat thisissue as a knapsack problem, incorporating both-side fairnessas constraints.In this paper, we adopt a novel perspective, treating eachrecommendation list as a runway rather than a knapsack. Inthis perspective, each item on the runway gains a velocity andruns within a specific time, achieving re-ranking for both-sidefairness. Meanwhile, we ensure the Minimum Utility Guaranteefor personalized recommendations by designing a Binary Searchapproach. This can provide more reliable recommendations com#2;pared to the conventional greedy strategy based on the knapsackproblem. We further broaden the applicability of FairSort,designing two versions for online and offline recommendationscenarios. Theoretical analysis and extensive experiments on real#2;world datasets indicate that FairSort can ensure more reliablepersonalized recommendations while considering fairness forboth the provider and user.
分类： 核科学技术 >> 辐射物理与技术 提交时间： 2024-07-12
摘要： 研究了在 700 ◦C 高温下暴露的 UNS N10003 合金激光焊缝的微观组织和拉伸断裂机制的演变。暴露 100 小时后，熔合区中初生共晶 M6C-γ 碳化物周围析出了细小的 M6C 碳化物。在长期热暴露过程中，细小的 M6C 碳化物的尺寸增大。当暴露时间延长至 10 000 小时时，焊态熔合区中的共晶 M6C-γ 碳化物转变为球形 M6C 碳化物。此外，随着暴露时间的增加，球形 M6C 颗粒的尺寸出现粗化。共晶 M6C-γ 碳化物的演变和 M6C 碳化物的粗化不会对焊接接头的拉伸性能产生不利影响。
分类： 医学、药学 >> 临床医学 提交时间： 2020-02-26
Jinnong,Zhang
Wenjing,Wang
Bo,Peng
Wei,Peng
Yisheng,Zhang
Yaling,Wang
Yan,Wan
Jiang,Chang
Ling,Mao
Xiaoping，Miao
Yifan,Zhou
Yanan,Li
Yu,Hu
Bo,Hu
摘要： Background: The efficient transmission of Severe Acute Respiratory Syndrome-2 Coronavirus (SARS-CoV-2) from patients to healthcare workers or family members has been a worrisome and prominent feature of the ongoing outbreak. On the basis of clinical practice and in-vitro studies, we postulated that post-exposure prophylaxis (PEP) using Arbidol is associated with decreased infection among individuals exposed to confirmed cases of COVID-19 infection. Methods: We conducted a retrospective case-control study on family members and health care workers who were exposed to patients confirmed to have SARS-CoV-2 infection by real-time RT-PCR and Chest CT from January 1 to January 16, 2020. We collected demographic information, work location of exposure, post-exposure prophylaxis information, and symptoms, if any, 24 days after exposure. The relation between post-exposure prophylaxis and infection in household contacts and healthcare workers were respectively analyzed. Results: 27 families and 124 health care workers had evidence of close exposure to patients with confirmed COVID-19. There were no differences in age, profession and sex distribution in the two groups with different post-exposure prophylaxis, table 1. Logistic regression based on the data of the family members and health care workers with Arbidol or Oseltamivir prophylaxis showed that Arbidol PEP was a strong protective factor against the development of COVID-19 (Odds ratio 0·011 , 95% CI 0·001-0·125, P=0·0003 for family members and Odds ratio 0·049, 95%CI 0·003-0·717), P= 0·0276 for health care workers). On the contrary, Oseltamivir was associated with an increase in COVID-19 infection (Odds ratio 20·446, 95% CI 1·407-297·143, P= 0·0271). Conclusions: Our findings suggest Arbidol could reduce the infection risk of the novel coronavirus in hospital and family settings. This treatment should be promoted for PEP use and should be the subject of further investigation.
分类： 生物学 >> 生态学 提交时间： 2018-01-10
摘要： The health risks associated with the consumption of rice may decrease if consumers use cooking practices which can reduce the concentrations of metal(loid)s and their bioaccessibility. The effects of cooking on the bioaccessibility of Cd and As in three contamination levels of rice were studied. The results indicated that cooking reduced bioaccessibility of Cd and As in rice. Cooking resulted in a significant increase in Cd and As concentrations in the residual fraction. Low volume cooking rice to dryness remove total Cd by about 10% for rice A and B, while middle or high volume water had no effect on Cd bioaccessibility in all rice types. In contrast, low volume cooking did not remove As, but a significant decrease was observed when cooking with middle or high volume water. This study provides information for a better understanding of more realistic estimation of metal(loid)s exposure from rice and the possible health risks.
分类： 生物学 >> 生物物理学 >> 生物物理、生物化学与分子生物学 提交时间： 2016-05-11
Liu Ying
Mo Wei-Chuan
Fu Jing-Peng
Liu Ying
He Rong-Qiao
Fu Jing-Peng
Liu Ying
He Rong-Qiao
Ding Hai-Min
Hua Qian
摘要： It has been established that exposure in the hypomagnetic field (HMF), which is one of the environmental factor of outer space, has adverse effects on animal and human behavior and brain function. Thus, it is necessary to develop appropriate counteract strategy to avoid the HMF-induced risks to the health of the astronauts during long-term and long-distance manned space mission. However, the physical and mental effects of the HMF in details still await systematic evaluation and the underlying mechanism remains elusive, so far. In this study, we constructed an HMF animal rearing system (<500 nT) and examined the effects of one-month HMF exposure on the circadian behavior, pain response and emotions in adult male C57BL/6 mice (4 similar to 6 weeks old, (20 +/- 2) g). The control animals were reared in the geomagnetic field (GMF). The HMF-exposed animals exhibited a prolonged alteration of the circadian drinking rhythm and a decrease in general activity, accompanied with an increase in thermal hyperalgesia. But the HMF did not induce obvious depression-like and anxiety-related behaviors. The serum noradrenalin concentration in HMF-exposed mice significantly decreased. These findings indicate that the HMF disturbs the behavior rhythm and the function of endocrine system, which probably leads to the subsequently weakened activities of the animal.
分类： 生物学 >> 生物物理学 提交时间： 2016-05-11
Zhao, Jiating
Gao, Yuxi
Peng, Xiaomin
Li, Yunyun
Xu, Xiaohan
Li, Bai
Dong, Juncai
Li, Yu-Feng
Pu, Yunxia
Wu, Gang
Zhu, Nali
摘要： A comprehensive approach that can identify and quantify selenium (Se) in seleno-proteins in Se-enriched yeast was developed. The Se-containing compounds in Se-enriched yeast were first extracted and then the fraction of Se-containing proteins in the supernatant was analyzed by 2-dimensional electrophoresis (2-DE) and synchrotron radiation X-ray fluorescence (SR-XRF). The detection limit (DL) of SR-XRF analysis for Se quantification in Se-containing proteins after 2-DE separation was calculated to be 0.20 mu g g(-1), which is suitable for Se quantification in the Se-containing spots present on the 2-D gel. After being scanned by SR-XRF, only spots with a mean Se content exceeding twice the DL of SR-XRF were considered to be seleno-proteins. In this way, a total of 157 Se-containing spots in the gel were visually distinguished. Se contents in all the Se-containing proteins of different molecular weights were quantified. The total Se content on the 2-D gel was calculated to be 126.56 mu g g(-1), which covered most of the seleno-proteins on the 2-D gel.
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