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Effective Elimination of Hazardous Chromium (VI) Using Periodic Elements and Contemporary Adsorption Methods by Using Magnesium Ferrite Nanoparticle: A Review
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作者 Nazmun Nahar Mahabub Hossain Swaron +1 位作者 Md. Aliuzzaman Sheik Md. Jamal Uddin 《Journal of Environmental Protection》 2024年第5期596-619,共24页
A well-known hazardous metal and top contaminant in wastewater is hexavalent chromium. The two forms of most commonly found chromium are chromate ( CrO 4 2− ) and dichromate ( Cr 2 O 7 2− ). Leather tanning, cooling t... A well-known hazardous metal and top contaminant in wastewater is hexavalent chromium. The two forms of most commonly found chromium are chromate ( CrO 4 2− ) and dichromate ( Cr 2 O 7 2− ). Leather tanning, cooling tower blow-down, plating, electroplating, rinse water sources, anodizing baths etc. are the main sources of Cr (VI) contamination. The Cr (VI) is not only non-biodegradable in the environment but also carcinogenic to living population. It is still difficult to treat Cr contaminated waste water effectively, safely, eco-friendly, and economically. As a result, many techniques have been used to treat Cr (VI)-polluted wastewater, including adsorption, chemical precipitation, coagulation, ion-exchange, and filtration. Among these practices, the most practical method is adsorption for the removal of Cr (VI) from aqueous solutions, which has gained widespread acceptance due to the ease of use and affordability of the equipment and adsorbent. It has been revealed that Fe-based adsorbents’ oxides and hydroxides have high adsorptive potential to lower Cr (VI) content below the advised threshold. Fe-based adsorbents were also discovered to be relatively cheap and toxic-free in Cr (VI) treatment. Fe-based adsorbents are commonly utilized in industry. It has been discovered that nanoparticles of Fe-, Ti-, and Cu-based adsorbents have a better capacity to remove Cr (VI). Cr (VI) was effectively removed from contaminated water using mixed element-based adsorbents (Fe-Mn, Fe-Ti, Fe-Cu, Fe-Zr, Fe-Cu-Y, Fe-Mg, etc.). Initial findings suggest that Cr (VI) removal from wastewater may be accomplished by using magnesium ferrite nanomaterials as an efficient adsorbent. 展开更多
关键词 Chromium (VI) Periodic Elements Adsorption elimination Magnesium Ferrite
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Experiences of Mothers on the Utilization of Elimination of Mother to Child Transmission of HIV Services at Mtendere Clinic, Lusaka
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作者 Ireen Kasongo Silavwe Patricia Katowa Mukwato +2 位作者 Sebean Mayimbo Febiano Phiri Laura Lubinda 《Journal of Biosciences and Medicines》 2024年第4期298-318,共21页
Introduction: Acquired immunodeficiency syndrome is one of the leading causes of mortality among women of reproductive age and Mother to Child Transmission of Human immunodeficiency virus is still a challenge affectin... Introduction: Acquired immunodeficiency syndrome is one of the leading causes of mortality among women of reproductive age and Mother to Child Transmission of Human immunodeficiency virus is still a challenge affecting many countries. Globally, an estimation of 180,000 children under 15 years acquire the Human immunodeficiency virus every day, and more than 90% of those infections are due to Mother to Child Transmission. The study sought to explore the experiences of mothers on the Elimination of Mother to Child Transmission-HIV services at Mtendere Clinic, Lusaka. Materials and Methods: Qualitative interpretive phenomenology study design was employed using in-depth interviews to collect data from a sample that was selected using purposive sampling technique. Thirteen participants were recruited, and these were HIV-positive mothers at least between the ages of 15 and 49 years and enrolled in the Elimination of Mother To Child Transmission-HIV program. The in-depth interviews were audiotape recorded and transcribed verbatim. Data was analyzed using thematic method. Findings: Three main themes that emerged are;living with HIV, support system and barriers to utilization of Elimination of Mother To Child Transmission-HIV services. Most of the participants expressed having acquired knowledge from the program, and received counselling and support from spouses, family as well as health personnel at Mtendere health facility which culminated into a positive experience and enhanced their uptake of the Elimination of Mother to Child Transmission-HIV services. However, barriers to service utilization were identified and these included fear of stigma, negative attitudes from health workers, long waiting times, lack of support and lack of transport to the health facility. Conclusion: Interventions such as community awareness campaigns on Elimination of Mother To Child Transmission-HIV, male involvement and implementing mother-to-mother peer support strategies in Elimination of Mother To Child Transmission-HIV service utilization should be prioritized so as to alleviate stigma and enhancing a positive experience for these mothers thus reducing on the Mother to Child HIV Transmission burden and mortality rates. 展开更多
关键词 elimination of Mother-to-Child Transmission Experiences Barriers UTILIZATION HIV/AIDS
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Brain-derived neurotrophic factor signaling in the neuromuscular junction during developmental axonal competition and synapse elimination
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作者 Josep Tomàs Víctor Cilleros-Mañé +7 位作者 Laia Just-Borràs Marta Balanyà-Segura Aleksandra Polishchuk Laura Nadal Marta Tomàs Carolina Silvera-Simón Manel M.Santafé Maria A.Lanuza 《Neural Regeneration Research》 SCIE CAS 2025年第2期394-401,共8页
During the development of the nervous system,there is an overproduction of neurons and synapses.Hebbian competition between neighboring nerve endings and synapses performing different activity levels leads to their el... During the development of the nervous system,there is an overproduction of neurons and synapses.Hebbian competition between neighboring nerve endings and synapses performing different activity levels leads to their elimination or strengthening.We have extensively studied the involvement of the brain-derived neurotrophic factor-Tropomyosin-related kinase B receptor neurotrophic retrograde pathway,at the neuromuscular junction,in the axonal development and synapse elimination process versus the synapse consolidation.The purpose of this review is to describe the neurotrophic influence on developmental synapse elimination,in relation to other molecular pathways that we and others have found to regulate this process.In particular,we summarize our published results based on transmitter release analysis and axonal counts to show the different involvement of the presynaptic acetylcholine muscarinic autoreceptors,coupled to downstream serine-threonine protein kinases A and C(PKA and PKC)and voltage-gated calcium channels,at different nerve endings in developmental competition.The dynamic changes that occur simultaneously in several nerve terminals and synapses converge across a postsynaptic site,influence each other,and require careful studies to individualize the mechanisms of specific endings.We describe an activity-dependent balance(related to the extent of transmitter release)between the presynaptic muscarinic subtypes and the neurotrophin-mediated TrkB/p75NTR pathways that can influence the timing and fate of the competitive interactions between the different axon terminals.The downstream displacement of the PKA/PKC activity ratio to lower values,both in competing nerve terminals and at postsynaptic sites,plays a relevant role in controlling the elimination of supernumerary synapses.Finally,calcium entry through L-and P/Q-subtypes of voltage-gated calcium channels(both channels are present,together with the N-type channel in developing nerve terminals)contributes to reduce transmitter release and promote withdrawal of the most unfavorable nerve terminals during elimination(the weakest in acetylcholine release and those that have already become silent).The main findings contribute to a better understanding of punishment-rewarding interactions between nerve endings during development.Identifying the molecular targets and signaling pathways that allow synapse consolidation or withdrawal of synapses in different situations is important for potential therapies in neurodegenerative diseases. 展开更多
关键词 acetylcholine release adenosine receptors axonal competition brain-derived neurotrophic factor calcium channels motor end-plate muscarinic acetylcholine receptors postnatal synapse elimination serine kinases tropomyosin-related kinase receptorB
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Elimination of lymphatic filariasis:Where do we stand so far? 被引量:2
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作者 Aashna Sinha Sudhashekhar Kumar +4 位作者 Deen Dayal Vaishali Yadav Atreyi Pramanik Kundan Kumar Chaubey Sanjay Kumar 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2023年第9期385-399,共15页
Lymphatic filariasis(LF),an asymptomatic,acute,and chronic condition in human beings,is the second most common vector-borne disease after malaria.According to the World Health Organization,there are 120 million LF cas... Lymphatic filariasis(LF),an asymptomatic,acute,and chronic condition in human beings,is the second most common vector-borne disease after malaria.According to the World Health Organization,there are 120 million LF cases detected in 81 tropical and subtropical countries,and one billion people are at risk.Therefore,the Global Program to Eliminate Lymphatic Filariasis was launched in 2000,with the primary objective of stopping LF transmission among all at-risk groups using mass drug administration(MDA),managing morbidities,and preventing LF-related impairments using a minimum treatment package.Additionally,other programs such as epidemiological assessment including National Filaria Control Program and World Health Organization recommended routine and pre-MDA microfilaremia surveys also implemented to stop the LF transmission.The routine filaria surveys were also carried out in around 2000-4000 individuals/month throughout the year whereas pre-MDA surveys were also conducted every year in approximately 4000 individuals in four fixed and four random sites.Furthermore,the Transmission Assessment Survey was also conducted to check the risk of LF among primary school children.Moreover,potential diagnostic methods,systematic surveillance regimes,the Direct Network Report system,and regular trainings and awareness may be also effective in preventing the recurrence of LF.Hence,this review emphasizes the potential advocacy tools and various strategies as well as procedures for monitoring,which could be impactful in eliminating LF. 展开更多
关键词 Lymphatic filariasis Treatment Challenges PROSPECT elimination
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Malaria slide bank plays a crucial role in achieving and sustaining malaria elimination in India 被引量:1
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作者 Shrikant Nema Nitika Nitika +1 位作者 Anup R Anvikar Praveen K Bharti 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2023年第10期431-433,共3页
India's healthcare system continues to place the highest priority on the fight against malaria[1].Malaria elimination program has received considerable attention from both the public and private sectors,resulting ... India's healthcare system continues to place the highest priority on the fight against malaria[1].Malaria elimination program has received considerable attention from both the public and private sectors,resulting in a significant drop in malaria cases[2].In 2022,a total of 176000 million cases of malaria were reported in India,in which Plasmodium(P.)falciparum has contributed 57.0%and 42.3%were P.vivax cases and limited cases of P.malariae and P.ovale. 展开更多
关键词 MALARIA MALARIA elimination
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Elimination mechanism of coal and gas outburst based on geo‑dynamic system with stress–damage–seepage interactions 被引量:1
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作者 Lingjin Xu Chaojun Fan +4 位作者 Mingkun Luo Sheng Li Jun Han Xiang Fu Bin Xiao 《International Journal of Coal Science & Technology》 EI CAS CSCD 2023年第4期47-61,共15页
Coal and gas outburst is a complex dynamic disaster during coal underground mining.Revealing the disaster mechanism is of great signifcance for accurate prediction and prevention of coal and gas outburst.The geo-dynam... Coal and gas outburst is a complex dynamic disaster during coal underground mining.Revealing the disaster mechanism is of great signifcance for accurate prediction and prevention of coal and gas outburst.The geo-dynamic system of coal and gas outburst is proposed.The framework of geo-dynamic system is composed of gassy coal mass,geological dynamic environment and mining disturbance.Equations of stress–damage–seepage interaction for gassy coal mass is constructed to resolve the outburst elimination process by gas extraction with boreholes through layer in foor roadway.The results show the occurrence of outburst is divided into the evolution process of gestation,formation,development and termination of geo-dynamic system.The scale range of outburst occurrence is determined,which provides a spatial basis for the prevention and control of outburst.The formation criterion and instability criterion of coal and gas outburst are established.The formation criterion F1 is defned as the scale of the geo-dynamic system,and the instability criterion F2 is defned as the scale of the outburst geo-body.According to the geo-dynamic system,the elimination mechanism of coal and gas outburst—‘unloading+depressurization’is established,and the gas extraction by boreholes through layer in foor roadway for outburst elimination is given.For the research case,when the gas extraction is 120 days,the gas pressure of the coal seam is reduced to below 0.4 MPa,and the outburst danger is eliminated efectively. 展开更多
关键词 Coal and gas outburst Geo-dynamic system Stress–damage–seepage coupling elimination mechanism Instability criterion Gas extraction
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R21 vaccine:A ray of hope for malaria elimination
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作者 Nitika Nitika Shrikant Nema Praveen Kumar Bharti 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2023年第6期243-244,共2页
The steady decline in malaria cases and deaths in recent years is a step ahead toward elimination;however,an increasing number of reports of antimalarial and insecticide resistance highlight the importance of having n... The steady decline in malaria cases and deaths in recent years is a step ahead toward elimination;however,an increasing number of reports of antimalarial and insecticide resistance highlight the importance of having newer approaches to achieve the goal in the stipulated time frame.Therefore,having an effective and durable malaria vaccine is extremely crucial,which can complement the tools currently in use.Although the malaria vaccine development efforts initiated in the 1910’s with the first attempts to develop a malaria vaccine involved inoculating humans with live,attenuated strains of the malaria parasite but the efforts have been intensified over the previous decade,resulting in several significant developments. 展开更多
关键词 MALARIA VACCINE elimination
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Status Report on the Elimination of Mother-to-Child Transmission (EMCT) of HIV at the Pikine National Hospital Center (CHNP), Dakar/Senegal
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作者 Fatou Ly Ablaye Faye +2 位作者 Adjaratou Fatou Kane Sakho Codou Sene Ndèye Fatou Sarr 《Open Journal of Pediatrics》 2023年第5期734-747,共14页
Introduction: For several years, the fight against the human immunodeficiency virus (HIV) has been a major public health issue in Africa. Since 2012, Senegal has adopted WHO option B+, consisting of systematic triple ... Introduction: For several years, the fight against the human immunodeficiency virus (HIV) has been a major public health issue in Africa. Since 2012, Senegal has adopted WHO option B+, consisting of systematic triple therapy for HIV-positive pregnant women, combined with breastfeeding and antiretroviral (ARV) prophylaxis for exposed newborns. It is in this dynamic that we set ourselves the objectives of evaluating the rate of transmission of HIV from mother to child and taking stock of the monitoring of children born to HIV-positive mothers at the Pediatric Department of the CHN of Pikine located in the Dakar suburbs. Methodology: Thus, we conducted a descriptive and analytical cross-sectional cohort follow-up study from 11/25/2014 to 03/09/2022 including all children born to HIV-positive mothers followed at the Pikine CHN since the start of care. Results: We had collected 51 children exposed to HIV and followed in our structure. They were exposed to HIV1 in 92% of cases. The HIV status of the mothers was known before pregnancy in more than half of the cases. The couples were serodiscordant in 56% of cases. The mothers were in clinical stage 1 of the disease in 69.6% of cases and were already under treatment in 47% of cases. The most used treatment regimen was ATRIPLA with Tenofovir (TDF) + Emtracitabine (FTC) + Efavirenz (EFV) in 59% of cases. Compliance was good in the majority of cases. The CD4 count during pregnancy was low in 10.6% of cases. The pregnancy was well followed in only 36.2% of cases. The mothers had given birth in our structure in 91.4% of cases. The vaginal route was found in 72.5% of cases and delivery was carried out by a midwife in 69.4% of cases. The average birth weight was 2733 ± 564. The majority of newborns had received antiretroviral (ARV) prophylaxis after birth, half of them between 12 and 24 hours. The most used therapeutic protocol was Zidovudine (AZT) + Lamivudine (3TC) + Lopinavir/Ritonavir (LPV/r). Protected breastfeeding was the option chosen in 76.8% of cases. The PCR performed at 6 weeks was negative in more than half of the cases. Retroviral serology was carried out after 14 months in 43% of cases. We noted a single positive case with a negative initial PCR, representing an overall transmission rate of 1.96%. Conclusion: Senegal’s current policy targeting EMTCT of HIV is on good momentum with a fairly low transmission rate thanks to screening of pregnant women and prophylaxis with antiretrovirals (ARV) for HIV-positive mothers during pregnancy and for life. And children exposed from birth and during breastfeeding up to 6 weeks with regular monitoring. 展开更多
关键词 elimination of Mother-to-Child Transmission HIV Pikine
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Preparation, characterization, and catalytic performance of high efficient CeO_2-MnO_x-Al_2O_3 catalysts for NO elimination 被引量:8
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作者 姚小江 李露露 +5 位作者 邹伟欣 虞硕涵 安继斌 李红丽 杨复沫 董林 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第8期1369-1380,共12页
A series of CeO2‐MnOx‐Al2O3 mixed oxide catalysts (Ce:Mn:Al mole ratio=6:4:x, x=0.25, 0.5, 1, 2) were prepared by a simple one‐step inverse co‐precipitation method to investigate the influence of the incorpo... A series of CeO2‐MnOx‐Al2O3 mixed oxide catalysts (Ce:Mn:Al mole ratio=6:4:x, x=0.25, 0.5, 1, 2) were prepared by a simple one‐step inverse co‐precipitation method to investigate the influence of the incorporation of Al3+ into CeO2‐MnOx mixed oxides. CeO2‐MnOx, CeO2‐Al2O3, and MnOx‐Al2O3 mixed oxides, and CeO2 were prepared by the same method for comparison. The samples were characterized by XRD, Raman, N2 physisorption, H2‐TPR, XPS, and in situ DRIFTS. The catalytic re‐duction of NO by CO was chosen as a model reaction to evaluate the catalytic performance. The incorporation of a small amount of Al3+into CeO2‐MnOx mixed oxides resulted in a decrease of crys‐tallite size, with the increase of the BET specific surface area and pore volume, as well as the in‐crease of Ce3+and Mn4+. The former benefits good contact between catalyst and reactants, and the latter promotes the adsorption of CO and the desorption, conversion and dissociation of adsorbed NO. All these enhanced the catalytic performance for the NO+CO model reaction. A reaction mecha‐nism was proposed to explain the excellent catalytic performance of CeO2‐MnOx‐Al2O3 catalysts for NO reduction by CO. 展开更多
关键词 Ceria-based mixed oxide Incorporation Electron interaction Adsorption property NO elimination
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In-situ Elimination Effect on Heavy Metals in Contaminated Soil from the Mining Area by Ramie 被引量:4
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作者 王冶 张兴 +3 位作者 揭雨成 佘玮 刑虎成 朱守晶 《Agricultural Science & Technology》 CAS 2012年第2期375-379,共5页
[Objective] The aim was to study on in-situ elimination effect on heavy metals in soil of the mining area by ramie (Boehmeria nivea (L.) Gaud.). [Methods] Based on Xiangzhu No.3 and Zhongzhu No.1, we conducted res... [Objective] The aim was to study on in-situ elimination effect on heavy metals in soil of the mining area by ramie (Boehmeria nivea (L.) Gaud.). [Methods] Based on Xiangzhu No.3 and Zhongzhu No.1, we conducted research on heavy metals contents of plants growing in soil of Qibao Mountain orefield in Liuyang, Hunan Province, and on characteristics of enrichment and transfer of heavy metals (Cu, Pb, Cd, Zn) under influence of the two ramie species. [Result] It was concluded that trend of Cu content in different parts of ramie was as follows: rootskinleafbone; trend of Pb was rootleafskinbone; trend of Cd was rootskinboneleaf; the trend of Zn was rootskinboneleaf. In farmland A (with low content of heavy metal), for per square meter of plough horizon, effect of Zhong 1 on heavy metals transferring volume and the period for restoration of the soil into national standard one (Category Ⅲ of Environmental Quality Standard for Soil) have been concluded. Specifically, for Cu, the corresponding values were 3 404.44 mg and 8.59 y, respectively; for Pb, the values were 3 638.5 mg and 13.52 y; for Cd, the values were 720.48 mg and 1.49 y; for Zn, the values were 37 324.8 mg and 0.67 y. [Conclusion] Soil contaminated by Cu, Pb, Cd, and Zn in orefield can be rapidly restored by growing ramie. 展开更多
关键词 RAMIE Mining area Contaminated Soil Heavy metal In-situ elimination
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Application of Wavelet Analysis toInterference Elimination for Geochemical Hydrocarbon Exploration 被引量:7
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作者 Zhang Liuping Ruan Tianjian Faculty of Earth Resources, China University of Geosciences, Wuhan 430074 《Journal of Earth Science》 SCIE CAS CSCD 2000年第1期91-93,共3页
Interference in the data of geochemical hydrocarbon exploration is a large obstacle for anomaly recognition. The multiresolution analysis of wavelet analysis can extract the information at different scales so as to pr... Interference in the data of geochemical hydrocarbon exploration is a large obstacle for anomaly recognition. The multiresolution analysis of wavelet analysis can extract the information at different scales so as to provide a powerful tool for information analysis and processing. Based on the analysis of the geometric nature of hydrocarbon anomalies and background, Mallat wavelet and symmetric border treatment are selected and data pre-processing (logarithm-normalization) is established. This approach provide good results in Shandong and Inner Mongolia, China. It is demonstrated that this approach overcome the disadvantage of backgound variation in the window (interference in window), used in moving average, frame filtering and spatial and scaling modeling methods. 展开更多
关键词 geochemical exploration petroleum exploration interference elimination wavelet analysis data processing anomaly recognition.
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Effect of pre-culture on virus elimination from in vitro apple by thermotherapy coupled with shoot tip culture 被引量:3
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作者 HU Guo-jun DONG Ya-feng +3 位作者 ZHANG Zun-ping FAN Xu-dong REN Fang LI Zheng-nan 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2018年第9期2015-2023,共9页
We evaluated the role of pre-culture on survival rate of in vitro apple plants treated by thermotherapy. Two apple cultivars, Malusxdomestica cv. Pink Lady and Huafu, were used in the experiment and both have widely g... We evaluated the role of pre-culture on survival rate of in vitro apple plants treated by thermotherapy. Two apple cultivars, Malusxdomestica cv. Pink Lady and Huafu, were used in the experiment and both have widely grown in China and infected with Apple chlorotic leafspot virus (ACLSV) and Apple stem grooving virus (ASGV). Results in growth and virus titer of apple plants did not exhibit clear trends during five different periods of pre-culture. Whilst, pre-culture increased the survival rate of the two cultivars during thermotherapy. The survival rate of plants pre-cultured for 13 d (P-13d) was 14 and 51% higher than that of P-ld plants for Pink Lady and Huafu, respectively. Moreover, pre-culture positively influenced regeneration of Huafu plants. The average survival rate of plants regenerated from P-ld and P-4d was 20% lower than that regenerated from P-7d, P-10d, and P-13d. The efficiency of virus eradication was determined by reverse-transcription PCR with two primer pairs for each virus, and the detection results showed that pre-culture scarcely affected apple virus elimination. Despite the fact that the two viruses were hardly detected at 5 d of thermotherapy, no virus-free plants were found in the two cultivars of regenerated apple plantlets after 30-d treatment. 展开更多
关键词 APPLE in vitro culture pre-culture THERMOTHERAPY virus elimination
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Experimental Studies on Elimination of Microbial Contamination by Hydroxyl Radicals Produced by Strong Ionization Discharge 被引量:4
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作者 白敏冬 张芝涛 +1 位作者 赵董艳 杨波 《Plasma Science and Technology》 SCIE EI CAS CSCD 2008年第4期463-465,共3页
Using fogdrops of OH^· radicals to eliminate microbial contamination is an effective way to solve the current domestic and international problem. The results show that the threshold of OH solution used in the exp... Using fogdrops of OH^· radicals to eliminate microbial contamination is an effective way to solve the current domestic and international problem. The results show that the threshold of OH solution used in the experiment is 0.6 mg/L, the lethal time is 1 s, and the spray density of OH solution is 21 μL/m^2. The experimental results show that the OH radical possesses the following advantages: celerity, low lethal concentration and spray density, short lethal time, and absence of secondary pollution. 展开更多
关键词 microbial contamination OH^· radical elimination technology
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ON-LINE ELIMINATION OF OIL WHIP 被引量:3
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作者 ZhengShuiying LiuShulian 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2005年第2期228-231,共4页
A new method to eliminate the oil whip online is put forward by use ofpassive electromagnetic damper. The damper works contactless and with DC current. Neither sensor norclosed loop control is needed. The dynamic equa... A new method to eliminate the oil whip online is put forward by use ofpassive electromagnetic damper. The damper works contactless and with DC current. Neither sensor norclosed loop control is needed. The dynamic equations of rotor-bearing system are built up bycombining d'Alemdert principle with Rize way, and the nonlinear oil film forces based on unsteadyshort bearing model are coupled to system. Such nonlinear equations are numerically solved byNewmark integration method. The calculated results show that the bifurcation behavior of the systemcan be. changed and the oil whip of the rotor may be well damped by external damping. Thebifurcation diagrams also show that the subharmonic vibration amplitude decreases in motion and thespeed at which the system losses its stability increases obviously by exerting external damping.Then experiments are carried out to demonstrate this phenomenon. It is observed that the complextrajectories of the journal motion are disappeared and the rotor-bearing system became stable whenthe power of passive electromagnetic damper is turned on. The experiments have good repeatability. 展开更多
关键词 Oil whip Rotor-bearing system elimination online
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Crosstalk elimination in multi-view autostereoscopic display based on polarized lenticular lens array 被引量:3
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作者 王志远 侯春萍 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第1期309-314,共6页
An autostereoscopic display composed of a directional backlight, an image display panel, a striped half-wave plate,and a polarized lenticular lens array is proposed. The directional backlight emitting the parallel lig... An autostereoscopic display composed of a directional backlight, an image display panel, a striped half-wave plate,and a polarized lenticular lens array is proposed. The directional backlight emitting the parallel light can redirect the cones of light to lenticular lens array and reduce the chromatic spatial-interference effect. The striped half-wave plate, located in front of the image display panel, transformed the polarization direction of the lights from the directional backlight into two mutually perpendicular directions. The polarized lenticular lens array not only can divide the light from the left and right view images to send to left and right eyes but also can reduce the crosstalk of the stereoscopic images. The proposed autostereoscopic display can produce high quality stereoscopic images without crosstalk at the optimal viewing distance. 展开更多
关键词 crosstalk elimination stereoscopic display lenticular lens
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Economic evaluation of the hepatitis C elimination strategy in Greece in the era of affordable direct-acting antivirals 被引量:2
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作者 Ilias Gountas Vana Sypsa +4 位作者 George Papatheodoridis Kyriakos Souliotis Kostas Athanasakis Homie Razavi Angelos Hatzakis 《World Journal of Gastroenterology》 SCIE CAS 2019年第11期1327-1340,共14页
BACKGROUND Hepatitis C virus(HCV) is a leading cause of worldwide liver-related morbidity and mortality. The World Health Organization released an integrated strategy targeting HCV-elimination by 2030. This study aims... BACKGROUND Hepatitis C virus(HCV) is a leading cause of worldwide liver-related morbidity and mortality. The World Health Organization released an integrated strategy targeting HCV-elimination by 2030. This study aims to estimate the required interventions to achieve elimination using updated information for direct-acting antiviral(DAA) treatment coverage, to compute the total costs(including indirect/societal costs) of the strategy and to identify whether the elimination strategy is cost-effective/cost-saving in Greece.AIM To estimate the required interventions and subsequent costs to achieve HCV elimination in Greece.METHODS A previously validated mathematical model was adapted to the Greek HCVinfected population to compare the outcomes of DAA treatment without the additional implementation of awareness or screening campaigns versus an HCV elimination strategy, which includes a sufficient number of treated patients. We estimated the total costs(direct and indirect costs), the disability-adjusted life years and the incremental cost-effectiveness ratio using two different price scenarios.RESULTS Without the implementation of awareness or screening campaigns,approximately 20000 patients would be diagnosed and treated with DAAs by2030. This strategy would result in a 19.6% increase in HCV-related mortality in2030 compared to 2015. To achieve the elimination goal, 90000 patients need to be treated by 2030. Under the elimination scenario, viremic cases would decrease by78.8% in 2030 compared to 2015. The cumulative direct costs to eliminate the disease would range from 2.1-2.3 billion euros(€) by 2030, while the indirect costs would be €1.1 billion. The total elimination cost in Greece would range from €3.2-3.4 billion by 2030. The cost per averted disability-adjusted life year is estimated between €10100 and €13380, indicating that the elimination strategy is very costeffective. Furthermore, HCV elimination strategy would save €560-895 million by2035.CONCLUSION Without large screening programs, elimination of HCV cannot be achieved. The HCV elimination strategy is feasible and cost-saving despite the uncertainty of the future cost of DAAs in Greece. 展开更多
关键词 HEPATITIS C elimination COST effectiveness COST of elimination Indirect COSTS Projections Mathematical modelling AWARENESS and screening programs World Health ORGANIZATION targets
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Towards hepatitis C virus elimination:Egyptian experience,achievements and limitations 被引量:2
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作者 Dalia Omran Mohamed Alboraie +10 位作者 Rania A Zayed Mohamed-Naguib Wifi Mervat Naguib Mohamed Eltabbakh Mohamed Abdellah Ahmed Fouad Sherief Sahar Maklad Heba Hamdy Eldemellawy Omar Khalid Saad Doaa Mohamed Khamiss Mohamed El Kassas 《World Journal of Gastroenterology》 SCIE CAS 2018年第38期4330-4340,共11页
Worldwide, more than one million people die each year from hepatitis C virus(HCV) related diseases, and over 300 million people are chronically infected with hepatitis B or C. Egypt used to be on the top of the countr... Worldwide, more than one million people die each year from hepatitis C virus(HCV) related diseases, and over 300 million people are chronically infected with hepatitis B or C. Egypt used to be on the top of the countries with heavy HCV burden. Some countries are making advances in elimination of HCV, yet multiple factors preventing progress; remain for the majority. These factors include lack of global funding sources for treatment, late diagnosis, poor data, and inadequate screening. Treatment of HCV in Egypt has become one of the top national priorities since 2007. Egypt started a national treatment program intending to provide cure for Egyptian HCV-infected patients. Mass HCV treatment program had started using Pegylated interferon and ribavirin between 2007 and 2014. Yet, with the development of highly-effective direct acting antivirals(DAAs) for HCV, elimination of viral hepatitis has become a real possibility. The Egyptian National Committee for the Control of Viral Hepatitis did its best to provide Egyptian HCV patients with DAAs. Egypt adopted a strategy that represents a model of care that could help other countries with high HCV prevalence rate in their battle against HCV. This review covers the effects of HCV management in Egyptian real life settings and the outcome of different treatment protocols. Also, it deals with the current and future strategies for HCV prevention and screening as well as the challenges facing HCV elimination and the prospect of future eradication of HCV. 展开更多
关键词 Hepatitis C virus Egypt Direct ACTING ANTIVIRALS screening elimination LIMITATIONS
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Global elimination of hepatitis C virus infection:Progresses and the remaining challenges 被引量:20
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作者 Reza Taherkhani Fatemeh Farshadpour 《World Journal of Hepatology》 CAS 2017年第33期1239-1252,共14页
Today, with the introduction of interferon-free direct-acting antivirals and outstanding progresses in the prevention, diagnosis and treatment of hepatitis C virus(HCV) infection, the elimination of HCV infection seem... Today, with the introduction of interferon-free direct-acting antivirals and outstanding progresses in the prevention, diagnosis and treatment of hepatitis C virus(HCV) infection, the elimination of HCV infection seems more achievable. A further challenge is continued transmission of HCV infection in high-risk population specially injecting drug users(IDUs) as the major reservoir of HCV infection. Considering the fact that most of these infections remain undiagnosed, unidentified HCVinfected IDUs are potential sources for the rapid spread of HCV in the community. The continuous increase in the number of IDUs along with the rising prevalence of HCV infection among young IDUs is harbinger of a forthcoming public health dilemma, presenting a serious challenge to control transmission of HCV infection. Even the changes in HCV genotype distribution attributed to injecting drug use confirm this issue. These circumstances create a strong demand for timely diagnosis and proper treatment of HCV-infected patients through risk-based screening to mitigate the risk of HCV transmission in the IDUs community and, consequently, in the society. Meanwhile, raising general awareness of HCV infection, diagnosis and treatment through public education should be the core activity of any harm reduction intervention, as the root cause of failure in control of HCV infection has been lack of awareness among young drug takers. In addition, effective prevention, comprehensive screening programs with a specific focus on high-risk population, accessibility to the new anti-HCV treatment regimens and public education should be considered as the top priorities of any health policy decision to eliminate HCV infection. 展开更多
关键词 Hepatitis C virus EPIDEMIOLOGY elimination Injecting drug user PREVENTION VACCINE Diagnosis Treatment
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Elimination of spiral waves and spatiotemporal chaos by the pulse with a specific spatiotemporal configuration 被引量:1
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作者 袁国勇 杨世平 +1 位作者 王光瑞 陈式刚 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第5期1925-1934,共10页
Spiral waves and spatiotemporal chaos are sometimes harmful and should be controlled. In this paper spiral waves and spatiotemporal chaos are successfully eliminated by the pulse with a very specific spatiotemporal co... Spiral waves and spatiotemporal chaos are sometimes harmful and should be controlled. In this paper spiral waves and spatiotemporal chaos are successfully eliminated by the pulse with a very specific spatiotemporal configuration. The excited position D of spiral waves or spatiotemporal chaos is first recorded at an arbitrary time (to). When the system at the domain D enters a recovering state, the external pulse is injected into the domain. If the intensity and the working time of the pulse are appropriate, spiral waves and spatiotemporal chaos can finally be eliminated because counter-directional waves can be generated by the pulse. There are two advantages in the method. One is that the tip can be quickly eliminated together with the body of spiral wave, and the other is that the injected pulse may be weak and the duration can be very short so that the original system is nearly not affected, which is important for practical applications. 展开更多
关键词 spiral wave spatiotemporal chaos elimination
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The Optimum Dosage Regimen of Intravenous Infusion for Drugs Obeying Parallel First-order and Michaelis-Menten Elimination Kinetics 被引量:1
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作者 Ding Yong(Department of Biomathematics,Nanjing Medical University,Nanjing 210029) 《生物数学学报》 CSCD 北大核心 1996年第4期6-11,共6页
For drugs obeying parallel first-order and Michaelis-Menten elimination kinetics,mathematical analysis concerning the optimum dosage regimen of intravenous infusion is conducted and following equations are derived:whe... For drugs obeying parallel first-order and Michaelis-Menten elimination kinetics,mathematical analysis concerning the optimum dosage regimen of intravenous infusion is conducted and following equations are derived:where Xo is the intravenous loading dose,Cb the plasma concentration level desired in clinical therapy,V the apparent distribution volume,k0 the rate constant of intravenouns infusion,K the first-order elimination rate constant,Vm the theoretical maximum rate of the Michaelis-Menten elimination process,Km the Michaelis constant.From this dosage regimen,plasma level maintains a constant Cb during the administration period.When K=0 the dosage regimen above is also suitable for drugs obeying Michaelis-Menten elimination kinetics. 展开更多
关键词 INTRAVENOUS infusion OPTIMUM dosage REGIMEN MICHAELIS-MENTEN elimination KINETICS Mathematical analysis
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