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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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Highly Thermoconductive,Strong Graphene‑Based Composite Films by Eliminating Nanosheets Wrinkles 被引量:2
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作者 Guang Xiao Hao Li +2 位作者 Zhizhou Yu Haoting Niu Yagang Yao 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第1期328-340,共13页
Graphene-based thermally conductive composites have been proposed as effective thermal management materials for cooling high-power electronic devices.However,when flexible graphene nanosheets are assembled into macros... Graphene-based thermally conductive composites have been proposed as effective thermal management materials for cooling high-power electronic devices.However,when flexible graphene nanosheets are assembled into macroscopic thermally conductive composites,capillary forces induce shrinkage of graphene nanosheets to form wrinkles during solution-based spontaneous drying,which greatly reduces the thermal conductivity of the composites.Herein,graphene nanosheets/aramid nanofiber(GNS/ANF)composite films with high thermal conductivity were prepared by in-plane stretching of GNS/ANF composite hydrogel networks with hydrogen bonds andπ-πinteractions.The in-plane mechanical stretching eliminates graphene nanosheets wrinkles by suppressing inward shrinkage due to capillary forces during drying and achieves a high in-plane orientation of graphene nanosheets,thereby creating a fast in-plane heat transfer channel.The composite films(GNS/ANF-60 wt%)with eliminated graphene nanosheets wrinkles showed a significant increase in thermal conductivity(146 W m^(−1)K^(−1))and tensile strength(207 MPa).The combination of these excellent properties enables the GNS/ANF composite films to be effectively used for cooling flexible LED chips and smartphones,showing promising applications in the thermal management of high-power electronic devices. 展开更多
关键词 GRAPHENE Aramid nanofiber Wrinkles elimination In-plane stretching Thermal conductivity
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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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Elimination of Computational Systematic Errors and Improvements of Weather and Climate System Models in Relation to Baroclinic Primitive Equations 被引量:2
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作者 钟青 陈家田 孙左令 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2002年第6期1103-1112,共10页
The design of a total energy conserving semi-implicit scheme for the multiple-level baroclinic primitive equation has remained an unsolved problem for a long time. In this work, however, we follow an energy perfect co... The design of a total energy conserving semi-implicit scheme for the multiple-level baroclinic primitive equation has remained an unsolved problem for a long time. In this work, however, we follow an energy perfect conserving semi-implicit scheme of a European Centre for Medium-Range Weather Forecasts (ECMWF) type sigma-coordinate primitive equation which has recently successfully formulated. Some real-data contrast tests between the model of the new conserving scheme and that of the ECMWF-type of global spectral semi-implicit scheme show that the RMS error of the averaged forecast Height at 850 hPa can be clearly improved after the first integral week. The reduction also reaches 50 percent by the 30th day. Further contrast tests demonstrate that the RMS error of the monthly mean height in the middle and lower troposphere also be largely reduced, and some well-known systematical defects can be greatly improved. More detailed analysis reveals that part of the positive contributions comes from improvements of the extra-long wave components. This indicates that a remarkable improvement of the model climate drift level can be achieved by the actual realizing of a conserving time-difference scheme, which thereby eliminates a corresponding computational systematic error source/sink found in the currently-used traditional type of weather and climate system models in relation to the baroclinic primitive equations. 展开更多
关键词 fidelity scheme computational systematical errors baroclinic primitive equation
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Prevalence of visual impairment and estimation of refractive errors among school children in Kakamega,Kenya 被引量:1
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作者 Isabel Signes-Soler Alfred Ragot +2 位作者 Sheilah Nangena Andrew Wekesa Raúl Montalbán Llamusí 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第5期932-939,共8页
AIM:To investigate the prevalence of visual impairment(VI)and provide an estimation of uncorrected refractive errors in school-aged children,conducted by optometry students as a community service.METHODS:The study was... AIM:To investigate the prevalence of visual impairment(VI)and provide an estimation of uncorrected refractive errors in school-aged children,conducted by optometry students as a community service.METHODS:The study was cross-sectional.Totally 3343 participants were included in the study.The initial examination involved assessing the uncorrected distance visual acuity(UDVA)and visual acuity(VA)while using a+2.00 D lens.The inclusion criteria for a subsequent comprehensive cycloplegic eye examination,performed by an optometrist,were as follows:a UDVA<0.6 decimal(0.20 logMAR)and/or a VA with+2.00 D≥0.8 decimal(0.96 logMAR).RESULTS:The sample had a mean age of 10.92±2.13y(range 4 to 17y),and 51.3%of the children were female(n=1715).The majority of the children(89.7%)fell within the age range of 8 to 14y.Among the ethnic groups,the highest representation was from the Luhya group(60.6%)followed by Luo(20.4%).Mean logMAR UDVA choosing the best eye for each student was 0.29±0.17(range 1.70 to 0.22).Out of the total,246 participants(7.4%)had a full eye examination.The estimated prevalence of myopia(defined as spherical equivalent≤-0.5 D)was found to be 1.45%of the total sample.While around 0.18%of the total sample had hyperopia value exceeding+1.75 D.Refractive astigmatism(cil<-0.75 D)was found in 0.21%(7/3343)of the children.The VI prevalence was 1.26%of the total sample.Among our cases of VI,76.2%could be attributed to uncorrected refractive error.Amblyopia was detected in 0.66%(22/3343)of the screened children.There was no statistically significant correlation observed between age or gender and refractive values.CONCLUSION:The primary cause of VI is determined to be uncorrected refractive errors,with myopia being the most prevalent refractive error observed.These findings underscore the significance of early identification and correction of refractive errors in school-aged children as a means to alleviate the impact of VI. 展开更多
关键词 visual impairment refractive errors MYOPIA AMBLYOPIA sustainable development goals
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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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Hemoperfusion and continuous veno-venous hemodiafiltration for eliminating chlorfenapyr in poisoning patients
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作者 Yanqing Liu Xiaoxia Lu +6 位作者 Haochun Wang Ming Niu Renzheng Zhang Zhongying Liu Limei Han Xiaobo Peng Xigang Zhang 《World Journal of Emergency Medicine》 SCIE CAS CSCD 2024年第3期235-237,共3页
Chlorfenapyr is a liposoluble insecticide belonging to the pyrrole family.Chlorfenapyr is activated when the N-ethoxymethyl side chain breaks,forming a toxic metabolite,which uncouples oxidative phosphorylation in the... Chlorfenapyr is a liposoluble insecticide belonging to the pyrrole family.Chlorfenapyr is activated when the N-ethoxymethyl side chain breaks,forming a toxic metabolite,which uncouples oxidative phosphorylation in the mitochondria,inhibits the production of adenosine triphosphate (ATP),and leads to the death of cells and targe organisms.[1] Symptoms of chlorfenapyr poisoning in patients are mild and atypical in the early stage,especially in patients receiving low dose exposure;however,such cases are rare and may be ignored by physicians,often leading to delayed treatment.[2,3]. 展开更多
关键词 PATIENTS PERFUSION eliminating
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Geometric Error Identification of Gantry-Type CNC Machine Tool Based on Multi-Station Synchronization Laser Tracers
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作者 Jun Zha Huijie Zhang 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2024年第2期150-162,共13页
Laser tracers are a three-dimensional coordinate measurement system that are widely used in industrial measurement.We propose a geometric error identification method based on multi-station synchronization laser tracer... Laser tracers are a three-dimensional coordinate measurement system that are widely used in industrial measurement.We propose a geometric error identification method based on multi-station synchronization laser tracers to enable the rapid and high-precision measurement of geometric errors for gantry-type computer numerical control(CNC)machine tools.This method also improves on the existing measurement efficiency issues in the single-base station measurement method and multi-base station time-sharing measurement method.We consider a three-axis gantry-type CNC machine tool,and the geometric error mathematical model is derived and established based on the combination of screw theory and a topological analysis of the machine kinematic chain.The four-station laser tracers position and measurement points are realized based on the multi-point positioning principle.A self-calibration algorithm is proposed for the coordinate calibration process of a laser tracer using the Levenberg-Marquardt nonlinear least squares method,and the geometric error is solved using Taylor’s first-order linearization iteration.The experimental results show that the geometric error calculated based on this modeling method is comparable to the results from the Etalon laser tracer.For a volume of 800 mm×1000 mm×350 mm,the maximum differences of the linear,angular,and spatial position errors were 2.0μm,2.7μrad,and 12.0μm,respectively,which verifies the accuracy of the proposed algorithm.This research proposes a modeling method for the precise measurement of errors in machine tools,and the applied nature of this study also makes it relevant both to researchers and those in the industrial sector. 展开更多
关键词 Multi-point positioning Multi-station synchronization CNC machine tool Geometric error error separation
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Bayesian Filtering for High-Dimensional State-Space Models With State Partition and Error Compensation
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作者 Ke Li Shunyi Zhao +1 位作者 Biao Huang Fei Liu 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第5期1239-1249,共11页
In the era of exponential growth of data availability,the architecture of systems has a trend toward high dimensionality,and directly exploiting holistic information for state inference is not always computationally a... In the era of exponential growth of data availability,the architecture of systems has a trend toward high dimensionality,and directly exploiting holistic information for state inference is not always computationally affordable.This paper proposes a novel Bayesian filtering algorithm that considers algorithmic computational cost and estimation accuracy for high-dimensional linear systems.The high-dimensional state vector is divided into several blocks to save computation resources by avoiding the calculation of error covariance with immense dimensions.After that,two sequential states are estimated simultaneously by introducing an auxiliary variable in the new probability space,mitigating the performance degradation caused by state segmentation.Moreover,the computational cost and error covariance of the proposed algorithm are analyzed analytically to show its distinct features compared with several existing methods.Simulation results illustrate that the proposed Bayesian filtering can maintain a higher estimation accuracy with reasonable computational cost when applied to high-dimensional linear systems. 展开更多
关键词 FILTERING ESTIMATION error
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A Combined Antenna Array Deployment with High Positioning Accuracy and Low Angular Measurement Error
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作者 Wangjie Chen Weiqiang Zhu +3 位作者 Zhenhong Fan Li Wu Yi He Yixiao Wang 《Journal of Beijing Institute of Technology》 EI CAS 2024年第2期141-154,共14页
In this paper,an antenna array composed of circular array and orthogonal linear array is proposed by using the design of long and short baseline“orthogonal linear array”and the circular array ambiguity resolution de... In this paper,an antenna array composed of circular array and orthogonal linear array is proposed by using the design of long and short baseline“orthogonal linear array”and the circular array ambiguity resolution design of multi-group baseline clustering.The effectiveness of the antenna array in this paper is verified by sufficient simulation and experiment.After the system deviation correction work,it is found that in the L/S/C/X frequency bands,the ambiguity resolution probability is high,and the phase difference system error between each channel is basically the same.The angle measurement error is less than 0.5°,and the positioning error is less than 2.5 km.Notably,as the center frequency increases,calibration consistency improves,and the calibration frequency points become applicable over a wider frequency range.At a center frequency of 11.5 GHz,the calibration frequency point bandwidth extends to 1200 MHz.This combined antenna array deployment holds significant promise for a wide range of applications in contemporary wireless communication systems. 展开更多
关键词 antenna array deployment ambiguity resolution phase consistency angle measurement error positioning error
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Prevalence of Refractive Errors among School Children Aged 5 to 15 Years Old at CHU-IOTA
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作者 Kadiatou Ba Aichata Tall +19 位作者 Mory Coulibaly Cheick Sogodogo Zoumana Bagayogo Aoua Ibrahim Toure Ousmane Toure Brainima Coulibaly Fatoumata Tata Sidibe Aly Konipo Roucky Sangare Seydou Diallo Moro Sidibe Oumar Diallo Assiatou Simaga Gounon Saye Modibo Sissoko Mamadou Kole Sidibe Sidi Diarra Nouhoum Guirou Abdoulaye Napo Adama Guindo 《Surgical Science》 2024年第8期480-491,共12页
Introduction: Undetected refractive errors constitute a health problem among school children who cannot take advantage of educational opportunities. The authors studied the prevalence of refractive errors in school ch... Introduction: Undetected refractive errors constitute a health problem among school children who cannot take advantage of educational opportunities. The authors studied the prevalence of refractive errors in school children aged 5 to 15 at CHU-IOTA. Patients and Method: This is a prospective, descriptive cross-sectional study carried out in the ophthalmic-pediatrics department of CHU-IOTA, from October to November 2023. Results: We received 340 school children aged 5 to 15, among whom 111 presented ametropia, i.e. a prevalence of 32.65%. The average age was 11.42 ± 2.75 years and a sex ratio of 0.59. The average visual acuity was 4/10 (range 1/10 and 10/10). We found refractive defects: astigmatism 73.87%, hyperopia 23.87% of cases and myopia 2.25%. The decline in distance visual acuity was the most common functional sign. Ocular abnormalities associated with ametropia were dominated by allergic conjunctivitis (26.13%) and papillary excavation (6.31%) in astigmatics;allergic conjunctivitis (9.01%) and papillary excavation (7.20%) in hyperopic patients;turbid vitreous (0.90%), myopic choroidosis (0.45%) and allergic conjunctivitis (0.45%) in myopes. Conclusion: Refractive errors constitute a reality and a major public health problem among school children. 展开更多
关键词 Refractive errors PREVALENCE CHILD CHU-IOTA
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Error field penetration in J-TEXT tokamak based on two-fluid drift-MHD model
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作者 王文 徐涛 +1 位作者 张仪 the J-TEXT team 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期545-551,共7页
An externally generated resonant magnetic perturbation can induce complex non-ideal MHD responses in their resonant surfaces.We have studied the plasma responses using Fitzpatrick's improved two-fluid model and pr... An externally generated resonant magnetic perturbation can induce complex non-ideal MHD responses in their resonant surfaces.We have studied the plasma responses using Fitzpatrick's improved two-fluid model and program LAYER.We calculated the error field penetration threshold for J-TEXT.In addition,we find that the island width increases slightly as the error field amplitude increases when the error field amplitude is below the critical penetration value.However,the island width suddenly jumps to a large value because the shielding effect of the plasma against the error field disappears after the penetration.By scanning the natural mode frequency,we find that the shielding effect of the plasma decreases as the natural mode frequency decreases.Finally,we obtain the m/n=2/1 penetration threshold scaling on density and temperature. 展开更多
关键词 plasma responses drift-MHD model error field penetration
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Determination of Timer Error and Evaluation of Its Effect on Dose for OB6, GammaBeam X200 and X-Ray Irradiators at the Secondary Standard Dosimetry Laboratory in Nigeria
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作者 Olumide Olaife Akerele Samuel Mofolorunsho Oyeyemi +3 位作者 David Olakanmi Olaniyi Francis Adole Agada Bamidele Musbau Adeniran Latifat Ronke Owoade 《World Journal of Nuclear Science and Technology》 CAS 2024年第2期118-130,共13页
Timer error as well as its convention is very important for dose accuracy during irradiation. This paper determines the timer error of irradiators at Secondary Standard Dosimetry Laboratory (SSDL) in Nigeria. The irra... Timer error as well as its convention is very important for dose accuracy during irradiation. This paper determines the timer error of irradiators at Secondary Standard Dosimetry Laboratory (SSDL) in Nigeria. The irradiators are Cs-137 OB6 irradiator and X-ray irradiators at the Protection level SSDL;and Co-60 irradiator at the Therapy Level SSDL. PTW UNIDOS electrometer and LS01 Ionization chamber were used at the Protection Level to obtain doses for both Cs-137 OB6 and X-ray irradiators while an IBA farmer type ionization chamber and an IBA DOSE 1 electrometer were used at the Protection Level SSDL. Single/multiple exposure method and graphical method were used in the determination of the timer error for the three irradiators. The timer error obtained for Cs-137 OB6 irradiator was 0.48 ± 0.01 s, the timer error for the X-ray irradiator was 0.09 ± 0.01 s while the timer error obtained for GammaBeam X200 was 1.21 ± 0.04 s. It was observed that the timer error is not affected by source to detector distance. It was also observed that the timer error of Co-60 Gamma X200 irradiator is increasing with the age of the machine. Source to detector distance and field size do not contribute towards the timer error of the irradiators. The timer error of the Co-60 Gamma X200 irradiator (the only irradiator among the irradiators with a pneumatic system) increases with the age of the irradiator. 展开更多
关键词 Timer error Irradiation SSDL Irradiators Dose Accuracy
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Resurgence of measles virus infection in an eliminated country, Sri Lanka
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作者 Merennage Anusha Yasanthi Fernando Gankandage Prabhath Chathuranga +2 位作者 Kaanthaka Gunaradha Abeygunasekara Dedunu Dias Weligamage Janaki Indira Abeynayake 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2024年第5期208-213,共6页
Objective:To describe the situation of measles in Sri Lanka from May to November,2023 and to define the role of virology laboratory towards case confirmation and epidemiological and genetic characterization of the out... Objective:To describe the situation of measles in Sri Lanka from May to November,2023 and to define the role of virology laboratory towards case confirmation and epidemiological and genetic characterization of the outbreak.Methods:This retrospective study analyzed all samples tested for measles from 1st of May to 30th of November,2023 at National Measles Rubella Laboratory,Sri Lanka.According to the World Health Organization(WHO)algorithm,serum and oropharyngeal/nasopharyngeal swabs were tested with WHO recommended kits for anti-measles IgM and measles virus specific RNA,respectively.Selected RNA positive samples were sequenced at reference laboratory,India.Analysis of sequencing data and construction of phylogenetic tree were carried out at National Measles Rubella Laboratory.Data was analyzed using descriptive statistics.Results:Of the total 1132 serum samples and 497 oropharyngeal/nasopharyngeal swabs from 1326 patients,657(49.5%)patients were confirmed as measles by anti-measles IgM,measles virus specific RNA or both.Males(55.6%,n=365)and the age group from>20 to≤30 years(33.0%,n=217)predominated positive patients.All provinces reported measles positive cases.All samples sequenced(100%,n=42)were genotype D8 with 95.2%(n=40)bearing Victoria.Australia origin.Conclusions:We described resurgence of measles in an eliminated country,confirming the genotype to be D8,one of the two genotypes currently circulating globally.Further,the study strongly convinced the importance of a strengthened virological surveillance system in an eliminated country,despite its eliminated status. 展开更多
关键词 Measles elimination Resurgence of measles Sri Lanka Genotype D8 National Measles Rubella Laboratory
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An Insight Survey on Sensor Errors and Fault Detection Techniques in Smart Spaces
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作者 Sheetal Sharma Kamali Gupta +2 位作者 DeepaliGupta Shalli Rani Gaurav Dhiman 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第3期2029-2059,共31页
The widespread adoption of the Internet of Things (IoT) has transformed various sectors globally, making themmore intelligent and connected. However, this advancement comes with challenges related to the effectiveness... The widespread adoption of the Internet of Things (IoT) has transformed various sectors globally, making themmore intelligent and connected. However, this advancement comes with challenges related to the effectiveness ofIoT devices. These devices, present in offices, homes, industries, and more, need constant monitoring to ensuretheir proper functionality. The success of smart systems relies on their seamless operation and ability to handlefaults. Sensors, crucial components of these systems, gather data and contribute to their functionality. Therefore,sensor faults can compromise the system’s reliability and undermine the trustworthiness of smart environments.To address these concerns, various techniques and algorithms can be employed to enhance the performance ofIoT devices through effective fault detection. This paper conducted a thorough review of the existing literature andconducted a detailed analysis.This analysis effectively links sensor errors with a prominent fault detection techniquecapable of addressing them. This study is innovative because it paves theway for future researchers to explore errorsthat have not yet been tackled by existing fault detection methods. Significant, the paper, also highlights essentialfactors for selecting and adopting fault detection techniques, as well as the characteristics of datasets and theircorresponding recommended techniques. Additionally, the paper presents amethodical overview of fault detectiontechniques employed in smart devices, including themetrics used for evaluation. Furthermore, the paper examinesthe body of academic work related to sensor faults and fault detection techniques within the domain. This reflectsthe growing inclination and scholarly attention of researchers and academicians toward strategies for fault detectionwithin the realm of the Internet of Things. 展开更多
关键词 error fault detection techniques sensor faults OUTLIERS Internet of Things
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