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甘蓝型油菜转录因子SRS基因家族的全基因组鉴定及表达分析
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作者 王龙 张永顺 +1 位作者 王红艳 肖麓 《中国油料作物学报》 CAS CSCD 北大核心 2024年第4期795-807,共13页
SRS(shi-related sequence)是植物特异的转录因子家族,在植物生长发育、激素信号转导和应对胁迫响应过程中发挥着重要的作用。为了研究SRS基因家族在甘蓝型油菜(Brassica napus L.)中潜在的生物学功能以及该基因家族在甘蓝型油菜形成过... SRS(shi-related sequence)是植物特异的转录因子家族,在植物生长发育、激素信号转导和应对胁迫响应过程中发挥着重要的作用。为了研究SRS基因家族在甘蓝型油菜(Brassica napus L.)中潜在的生物学功能以及该基因家族在甘蓝型油菜形成过程中的进化,利用比较基因组学的方法,在甘蓝型油菜及二倍体祖先种白菜(B.rapa L.)和甘蓝(B.oleracea L.)中分别鉴定到38、16和20个SRS基因,并对其理化性质、系统发育关系、基因结构、基因共线性、顺式作用元件和表达模式进行分析。结果表明,所有鉴定的SRS蛋白被分为9个分支,且甘蓝型油菜SRS基因家族的进化过程中发生了内含子/外显子的丢失事件。Ka/Ks分析发现,SRS基因在重复事件后经历了纯化选择。在多数的SRS基因启动子中发现了分别与光响应、厌氧诱导和脱落酸响应相关的顺式作用元件,且甘蓝型油菜SRS基因启动子比二倍体祖先启动子含有更多的胚乳基因表达和光响应顺式作用元件。转录组分析发现,甘蓝型油菜SRS基因在不同处理下以不同的表达模式响应并表现出根部的优势表达。综上,本研究为了解甘蓝型油菜SRS基因家族功能和作用提供初步的理论依据,为甘蓝型油菜及其二倍体祖先之间基因进化的分子机制提供参考。 展开更多
关键词 srs 基因家族 进化 转录组 甘蓝型油菜
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弓形虫srs19d基因敲除株的构建及其在宿主细胞中的生物学功能分析
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作者 牛水珠 潘明 +1 位作者 葛层层 黄思扬 《中国兽医杂志》 CAS 北大核心 2024年第8期10-17,共8页
为探究弓形虫表面抗原1相关序列(SRS)蛋白家族新成员SRS19D的功能,本试验以弓形虫Ⅱ型Pru虫株为亲本,运用成簇规律间隔短回文重复-CRISPR相关蛋白9(CRISPR/Cas9)技术构建了PruΔsrs 19 d敲除虫株,并进行了噬斑试验、细胞内增殖试验、体... 为探究弓形虫表面抗原1相关序列(SRS)蛋白家族新成员SRS19D的功能,本试验以弓形虫Ⅱ型Pru虫株为亲本,运用成簇规律间隔短回文重复-CRISPR相关蛋白9(CRISPR/Cas9)技术构建了PruΔsrs 19 d敲除虫株,并进行了噬斑试验、细胞内增殖试验、体外缓殖子转化试验、小鼠毒力试验和小鼠脑包囊检测试验。噬斑试验和细胞内增殖试验结果显示,与Pru虫株相比,PruΔsrs 19 d敲除虫株在人包皮成纤维(HFF)细胞上形成的噬斑显著变小(P<0.05),纳虫泡内形成的速殖子个数显著减少(P<0.05)。体外缓殖子转化试验发现,与Pru虫株相比,PruΔsrs 19 d敲除虫株的体外缓殖子转化率极显著降低(P<0.01)。小鼠毒力试验结果显示,与Pru虫株相比,弓形虫PruΔsrs 19 d敲除虫株不会引起ICR小鼠的死亡(P<0.05)。小鼠脑包囊检测试验结果显示,与Pru虫株相比,PruΔsrs 19 d敲除虫株感染小鼠后形成的脑包囊数量极显著减少(P<0.01)。本试验成功构建了弓形虫PruΔsrs 19 d敲除虫株,发现srs 19 d基因在弓形虫的体外生长、复制、毒力和慢性感染中发挥重要作用,为进一步探究SRS19D的功能和作用机制提供参考。 展开更多
关键词 弓形虫 表面抗原1相关序列(srs) srs19d 成簇规律间隔短回文重复-CRISPR相关蛋白9(CRISPR/Cas9) 生物学功能
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Dynamic Update Scheme of Spectrum Information Based on Spectrum Opportunity Incentive in the Database-Assisted Dynamic Spectrum Management
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作者 Zhang Yu Chen Yong +1 位作者 He Panfeng Cai Yueming 《China Communications》 SCIE CSCD 2024年第3期75-90,共16页
To solve the problem of delayed update of spectrum information(SI) in the database assisted dynamic spectrum management(DB-DSM), this paper studies a novel dynamic update scheme of SI in DB-DSM. Firstly, a dynamic upd... To solve the problem of delayed update of spectrum information(SI) in the database assisted dynamic spectrum management(DB-DSM), this paper studies a novel dynamic update scheme of SI in DB-DSM. Firstly, a dynamic update mechanism of SI based on spectrum opportunity incentive is established, in which spectrum users are encouraged to actively assist the database to update SI in real time. Secondly, the information update contribution(IUC) of spectrum opportunity is defined to describe the cost of accessing spectrum opportunity for heterogeneous spectrum users, and the profit of SI update obtained by the database from spectrum allocation. The process that the database determines the IUC of spectrum opportunity and spectrum user selects spectrum opportunity is mapped to a Hotelling model. Thirdly, the process of determining the IUC of spectrum opportunities is further modelled as a Stackelberg game by establishing multiple virtual spectrum resource providers(VSRPs) in the database. It is proved that there is a Nash Equilibrium in the game of determining the IUC of spectrum opportunities by VSRPs. Finally, an algorithm of determining the IUC based on a genetic algorithm is designed to achieve the optimal IUC. The-oretical analysis and simulation results show that the proposed method can quickly find the optimal solution of the IUC, and ensure that the spectrum resource provider can obtain the optimal profit of SI update. 展开更多
关键词 database-assisted dynamic spectrum management HOTELLING information updating contribution spectrum information updating STACKELBERG
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Correction:Brillouin scattering spectrum for liquid detection and applications in oceanography
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作者 Yuanqing Wang Jinghao Zhang +6 位作者 Yongchao Zheng Yangrui Xu Jiaqi Xu Jiao Jiao Yun Su Hai-Feng Lü Kun Liang 《Opto-Electronic Advances》 SCIE EI CAS CSCD 2024年第1期47-47,共1页
After publication of this article1,it was brought to our at-tention that the mathematical expressions‘‰’were mis-takenly replaced by‘%’for salinities.Details are listed below.1.In the last sentence in abstract,“... After publication of this article1,it was brought to our at-tention that the mathematical expressions‘‰’were mis-takenly replaced by‘%’for salinities.Details are listed below.1.In the last sentence in abstract,“approximately 0.1℃and 0.5%”should be“approximately 0.1℃and 0.5‰”. 展开更多
关键词 SCATTERING LISTED spectrum
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Construction of a Cu@hollow TS-1 nanoreactor based on a hierarchical full-spectrum solar light utilization strategy for photothermal synergistic artificial photosynthesis
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作者 Sixian Zhu Qiao Zhao +5 位作者 Hongxia Guo Li Liu Xiao Wang Xiwei Qi Xianguang Meng Wenquan Cui 《Carbon Energy》 SCIE EI CAS CSCD 2024年第2期25-36,共12页
The artificial photosynthesis technology has been recognized as a promising solution for CO_(2) utilization.Photothermal catalysis has been proposed as a novel strategy to promote the efficiency of artificial photosyn... The artificial photosynthesis technology has been recognized as a promising solution for CO_(2) utilization.Photothermal catalysis has been proposed as a novel strategy to promote the efficiency of artificial photosynthesis by coupling both photochemistry and thermochemistry.However,strategies for maximizing the use of solar spectra with different frequencies in photothermal catalysis are urgently needed.Here,a hierarchical full-spectrum solar light utilization strategy is proposed.Based on this strategy,a Cu@hollow titanium silicalite-1 zeolite(TS-1)nanoreactor with spatially separated photo/thermal catalytic sites is designed to realize high-efficiency photothermal catalytic artificial photosynthesis.The space-time yield of alcohol products over the optimal catalyst reached 64.4μmol g−1 h−1,with the selectivity of CH3CH2OH of 69.5%.This rationally designed hierarchical utilization strategy for solar light can be summarized as follows:(1)high-energy ultraviolet light is utilized to drive the initial and difficult CO_(2) activation step on the TS-1 shell;(2)visible light can induce the localized surface plasmon resonance effect on plasmonic Cu to generate hot electrons for H2O dissociation and subsequent reaction steps;and(3)low-energy near-infrared light is converted into heat by the simulated greenhouse effect by cavities to accelerate the carrier dynamics.This work provides some scientific and experimental bases for research on novel,highly efficient photothermal catalysts for artificial photosynthesis. 展开更多
关键词 artificial photosynthesis full spectrum NANOREACTORS photothermal catalysis
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Floquet spectrum and universal dynamics of a periodically driven two-atom system
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作者 谢文柱 周正强 +2 位作者 李轩 崔思淼 孙明远 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期436-443,共8页
We investigate the Floquet spectrum and excitation properties of a two-ultracold-atom system with periodically driven interaction in a three-dimensional harmonic trap.The interaction between the atoms is changed by va... We investigate the Floquet spectrum and excitation properties of a two-ultracold-atom system with periodically driven interaction in a three-dimensional harmonic trap.The interaction between the atoms is changed by varying the s-wave scattering length in two ways,the cosine and the square-wave modulations.It is found that as the driving frequency increases,the Floquet spectrum exhibits two main features for both modulations,the accumulating and the spreading of the quasienergy levels,which further lead to different dynamical behaviors.The accumulation is associated with collective excitations and the persistent growth of the energy,while the spread indicates that the energy is bounded at all times.The initial scattering length,the driving frequency and amplitude can all significantly change the Floquet spectrum as well as the dynamics.However,the corresponding relation between them is valid universally.Finally,we propose a mechanism for selectively exciting the system to one specific state by using the avoided crossing of two quasienergy levels,which could guide preparation of a desired state in experiments. 展开更多
关键词 Floquet spectrum universal dynamics two-atom system avoided crossing
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Comparison of inebilizumab or rituximab in addition to glucocorticoid therapy for neuromyelitis optica spectrum disorders
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作者 Chu-Yuan Lou Yong Wang +4 位作者 Jia-Yuan Xing Teng Ma Lei Tao Xiao-Tang Wang Run-Sheng Wang 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第6期1073-1078,共6页
AIM:To investigate the short-term efficacy and safety of inebilizumab for neuromyelitis optica spectrum disorders(NMOSD).METHODS:A total of 33 patients with NMOSD treated with inebilizumab(Group INB,n=15)or rituximab(... AIM:To investigate the short-term efficacy and safety of inebilizumab for neuromyelitis optica spectrum disorders(NMOSD).METHODS:A total of 33 patients with NMOSD treated with inebilizumab(Group INB,n=15)or rituximab(Group RTX,n=18)in addition to high-dose glucocorticoids were included.Both groups underwent hormone shock therapy during the acute phase.Subsequently,Group INB received inebilizumab injections during the remission phase,while Group RTX received rituximab injections.A comparison of aquaporins 4(AQP4)titer values,peripheral blood B lymphocyte counts,and visual function recovery was conducted before and 8wk after treatment.Additionally,adverse reactions and patient tolerability were analyzed after using inebilizumab treatment regimes.RESULTS:Following inebilizumab treatment,there was a significantly improvement in the visual acuity of NMOSD patients(P<0.05),accompanied by a notable decrease in AQP4 titer values and B lymphocyte ratio(P<0.05).Moreover,inebilizumab treatment showed a partial effect in preventing optic nerve atrophy(P<0.05).However,there were no significant differences in other therapeutic effects compared to rituximab,which has previously demonstrated substantial therapeutic efficacy(P>0.05).Furthermore,inebilizumab exhibited higher safety levels than that of rituximab injections.CONCLUSION:The combination of inebilizumab and high-dose glucocorticoids proves to be effective.In comparison to rituximab injections,inebilizumab displays better tolerance and safety.Moreover,it demonstrates a partial effect in preventing optic nerve atrophy.Thus,it stands as an effective method to reduce the disability rates and improve the daily living ability of patients with NMOSD. 展开更多
关键词 neuromyelitis optica spectrum disorders inebilizumab RITUXIMAB GLUCOCORTICOIDS
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Blockchain-Based MCS Detection Framework of Abnormal Spectrum Usage for Satellite Spectrum Sharing Scenario
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作者 Ning Yang Heng Wang +3 位作者 Jingming Hu Bangning Zhang Daoxing Guo Yuan Liu 《China Communications》 SCIE CSCD 2024年第2期32-48,共17页
In this paper, the problem of abnormal spectrum usage between satellite spectrum sharing systems is investigated to support multi-satellite spectrum coexistence. Given the cost of monitoring, the mobility of low-orbit... In this paper, the problem of abnormal spectrum usage between satellite spectrum sharing systems is investigated to support multi-satellite spectrum coexistence. Given the cost of monitoring, the mobility of low-orbit satellites, and the directional nature of their signals, traditional monitoring methods are no longer suitable, especially in the case of multiple power level. Mobile crowdsensing(MCS), as a new technology, can make full use of idle resources to complete a variety of perceptual tasks. However, traditional MCS heavily relies on a centralized server and is vulnerable to single point of failure attacks. Therefore, we replace the original centralized server with a blockchain-based distributed service provider to enable its security. Therefore, in this work, we propose a blockchain-based MCS framework, in which we explain in detail how this framework can achieve abnormal frequency behavior monitoring in an inter-satellite spectrum sharing system. Then, under certain false alarm probability, we propose an abnormal spectrum detection algorithm based on mixed hypothesis test to maximize detection probability in single power level and multiple power level scenarios, respectively. Finally, a Bad out of Good(BooG) detector is proposed to ease the computational pressure on the blockchain nodes. Simulation results show the effectiveness of the proposed framework. 展开更多
关键词 blockchain hypothesis test mobile crowdsensing satellite communication spectrum sharing
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Dietary L-proline supplementation ameliorates autism-like behaviors and modulates gut microbiota in the valproic acid-induced mouse model of autism spectrum disorder
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作者 Jingjing Fang Ruixuan Geng +2 位作者 Seong-Gook Kang Kunlun Huang Tao Tong 《Food Science and Human Wellness》 SCIE CAS CSCD 2024年第5期2889-2905,共17页
The effective intervention strategy for autism spectrum disorder(ASD)are currently limited.Herein,we attempted to evaluate the potential of L-proline(Pro),a multifunctional amino acid,in ameliorating autismlike behavi... The effective intervention strategy for autism spectrum disorder(ASD)are currently limited.Herein,we attempted to evaluate the potential of L-proline(Pro),a multifunctional amino acid,in ameliorating autismlike behaviors and clarify the molecular mechanisms involved by using the typical valproic acid(VPA)-induced mouse model of ASD.Pro significantly attenuates repetitive behaviors and social dysfunction in ASD mice.The correlation analysis revealed that the beneficial effects of Pro on autism-like behaviors are related to the modulation of gut microbiota structure and composition.The histological analysis revealed that Pro could reverse the decrease of Nissl-positive cells in the prefrontal cortex(PFC)induced by VPA exposure.RNA sequencing demonstrated that Pro can also alter the PFC transcriptomic profile distinguished by the regulation of genes involved in Parkinson disease,neuroactive ligand-receptor interaction,oxidative phosphorylation,and mitogen activated protein kinase signaling pathway.Overall,dietary Pro supplementation may be a promising intervention strategy for ASD. 展开更多
关键词 L-PROLINE Autism spectrum disorder Gut microbiota Prefrontal cortex Behavior
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Periodic signal extraction of GNSS height time series based on adaptive singular spectrum analysis
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作者 Chenfeng Li Peibing Yang +1 位作者 Tengxu Zhang Jiachun Guo 《Geodesy and Geodynamics》 EI CSCD 2024年第1期50-60,共11页
Singular spectrum analysis is widely used in geodetic time series analysis.However,when extracting time-varying periodic signals from a large number of Global Navigation Satellite System(GNSS)time series,the selection... Singular spectrum analysis is widely used in geodetic time series analysis.However,when extracting time-varying periodic signals from a large number of Global Navigation Satellite System(GNSS)time series,the selection of appropriate embedding window size and principal components makes this method cumbersome and inefficient.To improve the efficiency and accuracy of singular spectrum analysis,this paper proposes an adaptive singular spectrum analysis method by combining spectrum analysis with a new trace matrix.The running time and correlation analysis indicate that the proposed method can adaptively set the embedding window size to extract the time-varying periodic signals from GNSS time series,and the extraction efficiency of a single time series is six times that of singular spectrum analysis.The method is also accurate and more suitable for time-varying periodic signal analysis of global GNSS sites. 展开更多
关键词 GNSS Time series Singular spectrum analysis Trace matrix Periodic signal
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Exploring impedance spectrum for lithium-ion batteries diagnosis and prognosis:A comprehensive review
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作者 Xinghao Du Jinhao Meng +2 位作者 Yassine Amirat Fei Gao Mohamed Benbouzid 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第8期464-483,I0010,共21页
Lithium-ion batteries have extensive usage in various energy storage needs,owing to their notable benefits of high energy density and long lifespan.The monitoring of battery states and failure identification are indis... Lithium-ion batteries have extensive usage in various energy storage needs,owing to their notable benefits of high energy density and long lifespan.The monitoring of battery states and failure identification are indispensable for guaranteeing the secure and optimal functionality of the batteries.The impedance spectrum has garnered growing interest due to its ability to provide a valuable understanding of material characteristics and electrochemical processes.To inspire further progress in the investigation and application of the battery impedance spectrum,this paper provides a comprehensive review of the determination and utilization of the impedance spectrum.The sources of impedance inaccuracies are systematically analyzed in terms of frequency response characteristics.The applicability of utilizing diverse impedance features for the diagnosis and prognosis of batteries is further elaborated.Finally,challenges and prospects for future research are discussed. 展开更多
关键词 Lithium-ion battery Impedance spectrum Temperature monitoring Failure diagnosis Health prognosis
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Aquaporin-4-IgG-seropositive neuromyelitis optica spectrum disorders:progress of experimental models based on disease pathogenesis
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作者 Li Xu Huiming Xu Changyong Tang 《Neural Regeneration Research》 SCIE CAS 2025年第2期354-365,共12页
Neuromyelitis optica spectrum disorders are neuroinflammatory demyelinating disorders that lead to permanent visual loss and motor dysfunction.To date,no effective treatment exists as the exact causative mechanism rem... Neuromyelitis optica spectrum disorders are neuroinflammatory demyelinating disorders that lead to permanent visual loss and motor dysfunction.To date,no effective treatment exists as the exact causative mechanism remains unknown.Therefore,experimental models of neuromyelitis optica spectrum disorders are essential for exploring its pathogenesis and in screening for therapeutic targets.Since most patients with neuromyelitis optica spectrum disorders are seropositive for IgG autoantibodies against aquaporin-4,which is highly expressed on the membrane of astrocyte endfeet,most current experimental models are based on aquaporin-4-IgG that initially targets astrocytes.These experimental models have successfully simulated many pathological features of neuromyelitis optica spectrum disorders,such as aquaporin-4 loss,astrocytopathy,granulocyte and macrophage infiltration,complement activation,demyelination,and neuronal loss;however,they do not fully capture the pathological process of human neuromyelitis optica spectrum disorders.In this review,we summarize the currently known pathogenic mechanisms and the development of associated experimental models in vitro,ex vivo,and in vivo for neuromyelitis optica spectrum disorders,suggest potential pathogenic mechanisms for further investigation,and provide guidance on experimental model choices.In addition,this review summarizes the latest information on pathologies and therapies for neuromyelitis optica spectrum disorders based on experimental models of aquaporin-4-IgG-seropositive neuromyelitis optica spectrum disorders,offering further therapeutic targets and a theoretical basis for clinical trials. 展开更多
关键词 AQUAPORIN-4 experimental model neuromyelitis optica spectrum disorder PATHOGENESIS
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Is a Mini-Screen for Fetal Alcohol Spectrum Disorder Feasible?
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作者 Tyler Mueller Devin Evavold +2 位作者 June-Yung Kim Marilyn G. Klug Larry Burd 《Open Journal of Pediatrics》 2024年第4期767-781,共15页
Background: Fetal Alcohol Spectrum Disorders (FASDs) are a global public health concern with lifelong consequences for affected individuals. Recent prevalence studies suggest FASD prevalence rates range from 1-5% amon... Background: Fetal Alcohol Spectrum Disorders (FASDs) are a global public health concern with lifelong consequences for affected individuals. Recent prevalence studies suggest FASD prevalence rates range from 1-5% among school age children. Most people with FASD are not correctly diagnosed and inadequate screening to identify patients with increased risk may contribute to under-diagnosis. This study developed a 10-item screening tool for FASD and examined its feasibility. Methods: The sample consisted of 355 children who had been evaluated at an FASD clinic. Data from the 33-item Alcohol Related Neurodevelopmental Disorder Behavioral Checklist was used to develop a brief FASD screen by comparing the changes in Cronbach’s alpha for different combinations of items. The validity of the brief scale was then further examined using receiving operating characteristic analyses. Results: The 10-item screen demonstrated acceptable sensitivity, specificity, and accuracy to identify children at high risk for FASD. The percentage correctly classified was 91.3 and the area under the receiving operating characteristic curve was 0.971. Conclusions: This feasibility study demonstrated that a screen for FASD consisting of 10 items with yes or no responses can be completed in 3 - 4 minutes. The tool is brief, with a low administration burden and has acceptable epidemiologic performance characteristics including accuracy. Future research should examine the performance of this tool when used in larger, community-based populations where screening for FASD would be appropriate. 展开更多
关键词 Fetal Alcohol spectrum Disorders (FASDs) CHILDREN SCREENING PREVALENCE
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Increased Mortality Risk in Children with Fetal Alcohol Spectrum Disorders: A Scoping Review
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作者 Devin Evavold Tyler Mueller +2 位作者 Erika Johnson Marilyn G. Klug Larry Burd 《Open Journal of Pediatrics》 2024年第4期754-766,共13页
Objective: Fetal Alcohol Spectrum Disorders (FASDs) are common, often undiagnosed, lifelong developmental disorders that result from prenatal alcohol exposure. FASD is present at birth and typically identified around ... Objective: Fetal Alcohol Spectrum Disorders (FASDs) are common, often undiagnosed, lifelong developmental disorders that result from prenatal alcohol exposure. FASD is present at birth and typically identified around seven years of age. The most severe outcome in cases of FASD is mortality. The purpose of this scoping review is to 1) use a systematic review to provide an estimated mortality proportion for children with FASD, and 2) update a study published in 2014 by reviewing published reports of mortality in individuals diagnosed with FASD. Method: A search of PubMed, CINAHL, and Google Scholar for reports published between 2013 and 2023 on mortality in individuals with FASD. Results: Three population-based studies have reported on all-cause mortality rates, finding a combined mortality rate of 10.9%, a 2.63 fold (95% CI: 2.61 to 2.65) increase in mortality risk over the general population. Since 2016, this review identified only eight new cases meeting the study inclusion criteria. The reported causes of death were five cases of pneumonia, and one case each of failure to thrive and dehydration, intestinal dilatation and asphyxiation caused by overeating due to pica, and acute gastric volvulus. Discussion: While current research suggests a diagnosis of FASD is associated with a 2.6-fold increase in mortality risk, this is likely an underestimation, as most cases of FASD-related mortality go unreported. Globally, about 1 new case is reported every 15 months. However, in the United States alone, between 1752 to 4400 FASD related deaths occur annually. Our review suggests that FASD is rarely identified as a causal or contributing factor in deaths of children and adolescents, resulting in a substantial undercount of FASD-related deaths. Increased attention to the role of FASD in infant and child mortality case reviews, child death review committee reports, and mortality reviews is needed. 展开更多
关键词 Fetal Alcohol spectrum Disorders MORTALITY Birth Defects DEATH EXPOSURE PNEUMONIA
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Occurrence of K1 and K2 serotypes and genotypic characteristics of extended spectrumβ-lactamases-producing Klebsiella pneumoniae isolated from selected hospitals in Malaysia
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作者 Nurul Syazrah Anuar Hazmin Hazman +5 位作者 Sharven Raj Jeyakumar Mohd Nasir Mohd Desa Hasni Idayu Saidi Siti Norbaya Masri Nur Afiza Aziz Nurshahira Sulaiman 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2024年第1期30-38,共9页
Objective:To determine the distribution,phenotypic and genetic background of extended spectrumβ-lactamases(ESBL)-producing Klebsiella(K.)pneumoniae clinical isolates associated with K1 and K2 serotypes in two selecte... Objective:To determine the distribution,phenotypic and genetic background of extended spectrumβ-lactamases(ESBL)-producing Klebsiella(K.)pneumoniae clinical isolates associated with K1 and K2 serotypes in two selected hospitals in Malaysia.Methods:A total of 192 K.pneumoniae isolates were collected and subjected to antibiotic susceptibility,hypermucoviscosity test and multiplex PCR to detect the presence of K1-and K2-serotype associated genes.Multilocus sequence typing(MLST)was performed on ESBL-producing K.pneumoniae isolates presented with K1 and K2 serotypes,followed by phylogenetic analysis.Results:A total of 87 out of 192(45.3%)of the K.pneumoniae isolates collected were ESBL producers.However,only 8.3%(16/192)and 10.9%(21/192)of the total isolates were detected to carry K1-and K2-serotype associated genes,respectively.Statistical analysis showed that K1 and K2 capsular serotypes were not significantly associated with ESBL phenotype(P=0.196).However,they were significantly associated with hypervirulent,as demonstrated by the positive string test(P<0.001).MLST analysis revealed that ST23 as the predominant sequence type(ST)in the K1 serotype,while the ST in the K2 serotype is more diverse.Conclusions:Although the occurrence of ESBL-producing isolates among the hypervirulent strains was low,their coexistence warrants the need for continuous surveillance.MLST showed that these isolates were genetically heterogeneous. 展开更多
关键词 Extended spectrumβ-lactamases Klebsiella pneumoniae Capsular serotypes GENOTYPIC
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THE ABSENCE OF SINGULAR CONTINUOUS SPECTRUM FOR PERTURBED JACOBI OPERATORS
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作者 傅钲淇 黎雄 《Acta Mathematica Scientia》 SCIE CSCD 2024年第2期515-531,共17页
This paper is mainly about the spectral properties of a class of Jacobi operators(H_(c,b)u)(n)=c_(n)u(n+1)+c_(n-1)u(n-1)+b_(n)u(n),.where∣c_(n)−1∣=O(n^(−α))and b_(n)=O(n^(−1)).We will show that,forα≥1,the singula... This paper is mainly about the spectral properties of a class of Jacobi operators(H_(c,b)u)(n)=c_(n)u(n+1)+c_(n-1)u(n-1)+b_(n)u(n),.where∣c_(n)−1∣=O(n^(−α))and b_(n)=O(n^(−1)).We will show that,forα≥1,the singular continuous spectrum of the operator is empty. 展开更多
关键词 Jacobi operator singular continuous spectrum Prüfer variables
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Distinct and Additive Effects of Alcohol and Thiamine Deficiency in the Developing Brain: Relevance to Fetal Alcohol Spectrum Disorder
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作者 Suzanne M. de la Monte Elizabeth Silbermann Ming Tong 《Journal of Behavioral and Brain Science》 2024年第6期161-186,共26页
Background: Neurodevelopmental abnormalities in fetal alcohol spectrum disorder (FASD) are linked to brain insulin resistance and oxidative stress. However, the role of thiamine deficiency as a distinct or additive fa... Background: Neurodevelopmental abnormalities in fetal alcohol spectrum disorder (FASD) are linked to brain insulin resistance and oxidative stress. However, the role of thiamine deficiency as a distinct or additive factor in the pathogenesis of the neurodevelopmental and metabolic derangements in FASD has not been determined. Methods: Control and ethanol-exposed human PNET2 cerebellar neuronal cells and rat cerebellar slice cultures were treated with vehicle or pyrithiamine (Pyr) to assess independent and additive effects of thiamine deficiency on ethanol-mediated neurotoxicity, mitochondrial dysfunction, insulin resistance, inhibition of neuronal and glial genes, and oxidative stress. Results: Pyr treatments (0 - 200 µM) caused dose-dependent cell loss (Crystal Violet assay) and reduced mitochondrial function (MTT assay) in PNET2 neuronal cultures. Ethanol alone (100 mM) significantly reduced PNET2 neuronal viability, MTT activity, and ATP production. Over the broad dose range of Pyr treatment, ethanol significantly reduced ATP content and cell number and increased mitochondrial mass (MitoTracker Green). Ex vivo cerebellar slice culture studies revealed ethanol-induced developmental architectural disruption that was substantially worsened by Pyr. The adverse effects of ethanol were linked to increased lipid peroxidation and inhibition of asparatyl-asparaginyl-β-hydroxylase (ASPH) expression. The independent and additive effects of Pyr were associated with increased cytotoxicity, lipid peroxidation, Caspase 3 activation, and Tau accumulation. Conclusions: During development, alcohol exposure and thiamine deficiency exert distinct but overlapping molecular pathologies that ultimately impair the structure and function of cerebellar neurons. While both insults drive cell loss and mitochondrial dysfunction with increased lipid peroxidation, ethanol’s additional inhibitory effects on ASPH reflect impairments in insulin and IGF signaling. In contrast, Pyr’s main adverse effects were likely due to neurotoxicity and the activation of apoptosis cascades. The findings suggest that FASD severity may be reduced by thiamine supplementation, but without additional support for insulin/IGF signaling networks, FASD would not be prevented. 展开更多
关键词 Fetal Alcohol spectrum Disorder Thiamine Deficiency CEREBELLUM Slice Culture PYRITHIAMINE
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Joint Optimization for on-Demand Deployment of UAVs and Spectrum Allocation in UAVs-Assisted Communication
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作者 Chen Yong Liao Naiwen +2 位作者 WangWei Zhang Xianyu Zhang Yu 《China Communications》 SCIE CSCD 2024年第7期278-290,共13页
To improve the efficiency and fairness of the spectrum allocation for ground communication assisted by unmanned aerial vehicles(UAVs),a joint optimization method for on-demand deployment and spectrum allocation of UAV... To improve the efficiency and fairness of the spectrum allocation for ground communication assisted by unmanned aerial vehicles(UAVs),a joint optimization method for on-demand deployment and spectrum allocation of UAVs is proposed,which is modeled as a mixed-integer non-convex optimization problem(MINCOP).An algorithm to estimate the minimum number of required UAVs is firstly proposed based on the pre-estimation and simulated annealing.The MINCOP is then decomposed into three sub-problems based on the block coordinate descent method,including the spectrum allocation of UAVs,the association between UAVs and ground users,and the deployment of UAVs.Specifically,the optimal spectrum allocation is derived based on the interference mitigation and channel reuse.The association between UAVs and ground users is optimized based on local iterated optimization.A particle-based optimization algorithm is proposed to resolve the subproblem of the UAVs deployment.Simulation results show that the proposed method could effectively improve the minimum transmission rate of UAVs as well as user fairness of spectrum allocation. 展开更多
关键词 block coordinate descent method on-demand deployment spectrum allocation UAVs-assisted Communication
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Construction of a broadband impedance spectrum and synchronous DC voltammetry measurement system for solar cells
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作者 XIAO Wenbo LI Ao +1 位作者 WU Huaming LI Yongbo 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2024年第3期302-307,共6页
The current impedance spectroscopy measurement techniques face difficulties in diagnosing solar cell faults due to issues such as cost,complexity,and accuracy.Therefore,a novel system was developed for precise broadba... The current impedance spectroscopy measurement techniques face difficulties in diagnosing solar cell faults due to issues such as cost,complexity,and accuracy.Therefore,a novel system was developed for precise broadband impedance spectrum measurement of solar cells,which was composed of an oscilloscope,a signal generator,and a sampling resistor.The results demonstrate concurrent accurate measurement of the impedance spectrum(50 Hz-0.1 MHz)and direct current voltametric characteristics.Comparative analysis with Keithley 2450 data yields a global relative error of approximately 6.70%,affirming the accuracy.Among excitation signals(sine,square,triangle,pulse waves),sine wave input yields the most accurate data,with a root mean square error of approximately 13.3016 and a global relative error of approximately 4.25%compared to theoretical data.Elevating reference resistance expands the half circle in the impedance spectrum.Proximity of reference resistance to that of the solar cell enhances the accuracy by mitigating line resistance influence.Measurement error is lower in high-frequency regions due to a higher signal-to-noise ratio. 展开更多
关键词 solar cell OSCILLOSCOPE signal generator volt-ampere characteristics impedance spectrum
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A research on the effect of plasma spectrum collection device on LIBS spectral intensity
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作者 林晓梅 董艳杰 +5 位作者 林京君 黄玉涛 杨江飞 岳星宇 张倬嘉 段鑫杨 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第5期121-128,共8页
Only a small amount of spectral information is collected because the collection solid angle of the optical fiber probe and lens is very limited when collecting spectral information.To overcome this limitation,this stu... Only a small amount of spectral information is collected because the collection solid angle of the optical fiber probe and lens is very limited when collecting spectral information.To overcome this limitation,this study presents a novel method for acquiring plasma spectral information from various spatial directions.A parabolic-shaped plasma spectral collection device(PSCD)is employed to effectively collect more spectral information into the spectrometer,thereby enhancing the overall spectral intensity.The research objects in this study were soil samples containing different concentrations of heavy metals Pb,Cr,and Cd.The results indicate that the PSCD significantly enhances the spectral signal,with an enhancement rate of up to 45%.Moreover,the signal-to-noise ratio also increases by as much as 36%.Simultaneously,when compared to the absence of a device,it is found that there is no significant variation in plasma temperature when the PSCD is utilized.This observation eliminates the impact of the spatial effect caused by the PSCD on the spectral intensity.Consequently,a concentrationspectral intensity relationship curve is established under the PSCD.The results revealed that the linear fitting R^(2)for Pb,Cr,and Cd increased by 0.011,0.001,and 0.054,respectively.Additionally,the limit of detection(LOD)decreased by 0.361 ppm,0.901 ppm,and 0.602 ppm,respectively.These findings indicate that the spectral enhancement rate elevates with the increase in heavy metal concentration.Hence,the PSCD can effectively enhance the spectral intensity and reduce the detection limit of heavy metals in soil. 展开更多
关键词 LIBS plasma spectrum collection device spectral enhancement plasma temperature limit of detection
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