An efficient method for the synthesis of quinoxaline derivatives through oxidative coupling of o-phenylenediamines (OPD) with terminal alkynes by using copper-alumina (Cu-Al) catalyst was described. A series of Cu-Al ...
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An efficient method for the synthesis of quinoxaline derivatives through oxidative coupling of o-phenylenediamines (OPD) with terminal alkynes by using copper-alumina (Cu-Al) catalyst was described. A series of Cu-Al catalysts with different mole ratios of , 2:1 (Cu-Al-1), 2.5:1 (Cu-Al-2) and 3:1 (Cu-Al-3) were prepared by co-precipitation method followed by calcination and their activity was checked for the synthesis of quinoxaline derivatives. Cu-Al-2 showed excellent activity at in presence of . The catalyst is inexpensive, recyclable and environmentally benign. The fresh and recycled catalysts were characterized by different analytical techniques. Different reaction parameters were optimized;catalyst screening, solvent, base and temperature. The protocol was extended towards different substrates. Synopsis. An efficient, robust and recyclable catalyst (Cu-Al catalyst) was developed for the synthesis of quinoxaline. A series of Cu-Al with different molar ratios of , 2:1 (Cu-Al-1), 2.5:1 (Cu-Al-2) and 3:1 (Cu-Al-3) were prepared by co-precipitation method, followed by calcination and the activity of these catalysts was checked for the quinoxaline synthesis. Cu-Al-2 (2.5:1) was found to be the best catalyst with 95% yield of the desired product.
The ongoing debate surrounding the impact of the Internet Research Agency's (IRA) social media campaign during the 2016 U.S. presidential election has largely overshadowed the involvement of other actors. Our anal...
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The ongoing debate surrounding the impact of the Internet Research Agency's (IRA) social media campaign during the 2016 U.S. presidential election has largely overshadowed the involvement of other actors. Our analysis brings to light a substantial group of suspended Twitter users, outnumbering the IRA user group by a factor of 60, who align with the ideologies of the IRA campaign. Our study demonstrates that this group of suspended Twitter accounts significantly influenced individuals categorized as undecided or weak supporters, potentially with the aim of swaying their opinions, as indicated by Granger causality.
为更好地在国家级协学会层面展现升级版的杭州产业和会奖资源,充分展示杭州'新经济会议目的地'的独特魅力,8月27日下午,由杭州市文化广电旅游局主办的'杭州PLUS——杭州新经济会议目的地推介活动'在北京举行。'杭州会议大使'、浙江省科协副主席田梅,杭州市文化广电旅游局党组成员张安胜,国际会议与大会协会(ICCA)亚太区总监Noor Ahmad Hamid,中国科学技术协会学会服务中心学术活动处处长魏丹,中国科学技术协会学会服务中心创新服务处处长沈进,杭州国际博览中心总经理唐雪,杭州市商务会展旅游促进中心主任叶虹,杭州市商务会展旅游促进中心副主任杨保福等领导、嘉宾出席活动。学术会议买家,来自60家全国协学会以及30家专注服务学术会议的会议服务商(PCO)参会。学术会议服务商(卖家),来自杭州的18家优质会议公司、酒店等参加。目前杭州正大力打造数字经济第一城,用科技创新赋能杭州全产业集群化发展。以数字经济为代表的新经济产业呈现出飞速发展之势,新经济会议成为杭州会议市场增长的新引擎。让杭州作为新经济产业会议高地的理念更加深入人心,使杭州成为学术会议的首选城市。
The cascade of physiologic mechanisms in response to infection, the acute phase response, is recognized as having a major role in host defense. Two such responses are an increase in plasma copper and activation of the...
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The cascade of physiologic mechanisms in response to infection, the acute phase response, is recognized as having a major role in host defense. Two such responses are an increase in plasma copper and activation of the hypothalamic-pituitary-adrenal axis, which are consistently reported to occur during bacterial infection. We aimed to determine whether the alterations in plasma copper and corticosterone were conditionable using the conditioned taste aversion paradigm. The regime involved the pairing of a novel-tasting saccharine solution (the conditioned stimulus) with lipopolysaccharide (the unconditioned stimulus). Seven days after the initial pairing of these stimuli (the test day), the saccharine solution was represented. Animals exposed to this condition displayed a significant decrease in plasma copper levels. In addition, these rats experienced a reduction in plasma corticosterone that was time dependent. Paradoxically, the conditioned response of both these variables were in a direction contrary to that reported during bacterial infection. These results suggest that some acute phase responses may condition as a rebound response, or in an opposing trend to that occurring as the initial reaction.
Background: Alzheimer's disease and related disorders are characterized by cognitive impairment associated with behavioral and psychological symptoms of dementia. These symptoms have significant consequences for b...
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Background: Alzheimer's disease and related disorders are characterized by cognitive impairment associated with behavioral and psychological symptoms of dementia. These symptoms have significant consequences for both the patient and his family environment. While risk factors for behavioral disorders have been identified in several studies, few studies have focused on the evolution of these disorders. Moreover, it is important to identify factors linked to the long-term evolution of behavioral disorders, as well as patients' and caregivers' quality of life. Our purpose is to present the methodology of the EVITAL study, which primary objective is to determine the factors associated with the evolution of behavioral disorders among patients with Alzheimer's disease and related disorders during the year following their hospitalization in cognitive and behavioral units. Secondary objectives were 1) to assess the factors related to the evolution of behavioral disorders during hospitalization in cognitive and behavioral units;2) to identify the factors linked to patients' and caregivers' quality of life, as well as caregivers' burden;3) to assess the factors associated with rehospitalization of the patients for behavioral disorders in the year following their hospitalization in cognitive and behavioral units. Method/Design: A multicenter, prospective cohort of patients with Alzheimer's disease and related disorders as well as behavioral disorders who are hospitalized in cognitive and behavioral units. The patients will be included in the study for a period of 24 months and followed-up for 12 months. Socio-demographic and environmental data, behavioral disorders, medications, patients' and caregivers' quality of life as well as caregivers' burden will be assessed throughout hospitalization in cognitive and behavioral units. Follow-up will be performed at months 3, 6 and 12 after hospitalization. Socio-demographic and environmental data, behavioral disorders, medications, pat
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