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China Ocean Engineering 2014年第5期28卷 645-657页

作者： S.Sakthivel MURUGAN v.natarajan K.MAHESWARAN ECE Department SSN College of Engineering Instrumentation Department MIT Campus Anna University Infosys Chennai India

Sonar generated acoustic signals transmitted in underwater channel for distant communications are affected by numerous factors like ambient noise, making them nonlinear and non-stationary in nature. In recent years, the application of Empirical Mode Decomposition(EMD) technique to analyze nonlinear and non-stationary signals has gained much attention. It is an empirical approach to decompose a signal into a set of oscillatory modes known as intrinsic mode functions(IMFs). In general, Hilbert transform is used in EMD for the identification of oscillatory signals. In this paper a new EMD algorithm is proposed using FFT to identify and extract the acoustic signals available in the underwater channel that are corrupted due to various ambient noises over a range of 100 Hz to 10 kHz in a shallow water region. Data for analysis are collected at a depth of 5 m and 10 m offshore Chennai at the Bay of Bengal. The algorithm is validated for different sets of known and unknown reference signals. It is observed that the proposed EMD algorithm identifies and extracts the reference signals against various ambient noises. Significant SNR improvement is also achieved for underwater acoustic signals.

关键词： EMD IMF SNR ambient noises underwater acoustic signals FFT

Optimization of piezoelectric MEMS process on Sr and La co-doped PZT thin films

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Journal of Advanced Dielectrics 2020年第4期10卷 6-12页

作者： M.Kathiresan Jain Jose E.varadarajan R.Ramesh v.natarajan M.K.Jayaraj T.Santhanakrishnan Naval Physical and Oceanographic Laboratory DRDO Kochi-682021India Research Innovation Centre DRDO Chennai-600113India Department of Physics Cochin University of Science and Technology Kochi-682022 India Combat vehicle Research and Development Establishment DRDOChennai-600054India

Doped lead-zirconate-titanate(PZT)thin films are preferred for the development of micro-electro-mechanical systems(MEMS)-based acoustic sensors because of their inherent higher dielectric and piezoelectric *** process is used to develop such MEMS devices which is highly complex even for undoped PZT thin films;therefore,the problem is further cumbersome for doped PZT thin films due to the presence of added dopant elements and their associated *** paper presents patterning of strontium(Sr)and lanthanum(La)co-doped PZT thin film(PSLZT)deposited on platinized silicon substrate using wet and dry etching processes for fabricating a diaphragm structure with thickness of 15-25μm and diameter of 1.4-2 mm,suitable for acoustic sensing *** effects of various etching conditions have been studied and the results are *** is found that the dry etching is the most suited process for realizing the piezoelectric MEMS structure due to its higher etching *** appreciable etching rate of 260-270 nm/min with smooth vertical sidewalls is *** silicon diaphragm with patterned PSLZT thin film is found to retain more than 80%of its dielectric and piezoelectric coefficients and has a resonance of 1.43 MHz.

关键词： PZT etching RF sputtering Doped PZT Sr and La co-doping MEMS acoustic sensor

Optimization of Performance and Emission Characteristics of PPCCI Engine fuelled with Ethanol and Diesel blends Using Grey-Taguchi Method

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Journal of Thermal Science 2018年第1期27卷 89-94页

作者： S.natarajan K.Pitchandi N.v.Mahalakshmi Department of Mechanical Engineering Sri Venkateswara College of EngineeringSriperumbudur-602117TamilnaduIndia. Department of Mechanical Engineering Sri Venkatcswara College of EngineeringSriperumbudur-602117TamilnaduIndia. Internal combustion Engineering Division Department of Mechanical EngineeringCollege of EngineeringAnna UniversityChennai-600025TamilnaduIndia.

The performance and emission characteristics of a PPCCI engine fuelled with ethanol and diesel blends were car- ded out on a single cylinder air cooled CI engine. In order to achieve the optimal process response with a limited number of experimental cycles, multi objective grey relational analysis had been applied for solving a multiple response optimization problem. Using grey relational grade and signal-to-noise ratio as a performance index, a combination of input parameters was prefigured so as to achieve optimum response characteristics. It was observed that 20% premixed ratio of blend was most suitable for use in a PPCCI engine without significantly affecting the engine performance and emissions characteristics.

关键词： PPCCI Biodiesel Optimization Grey-Taguchi method

Autism spectrum disorder:difficulties in diagnosis and microRNA biomarkers

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Neural Regeneration Research 2025年第10期20卷 2776-2786页

作者： Bridget Martinez Philip v.Peplow Department of Pharmacology University of Nevada-RenoRenoNVUSA Department of Medicine University of Nevada-RenoRenoNVUSA Department of Anatomy University of OtagoDunedinNew Zealand

We performed a PubMed search for microRNAs in autism spectrum disorder that could serve as diagnostic biomarkers in patients and selected 17 articles published from January 2008 to December 2023,of which 4 studies were performed with whole blood,4 with blood plasma,5 with blood serum,1 with serum neural cell adhesion molecule L1-captured extracellular vesicles,1 with blood cells,and 2 with peripheral blood mononuclear *** of the studies involved children and the study cohorts were largely *** of the studies had performed microRNA sequencing or quantitative polymerase chain reaction assays to measure microRNA *** five studies had used real-time polymerase chain reaction assay to validate microRNA expression in autism spectrum disorder subjects compared to *** microRNAs that were validated in these studies may be considered as potential candidate biomarkers for autism spectrum disorder and include miR-500a-5p,-197-5p,-424-5p,-664a-3p,-365a-3p,-619-5p,-664a-3p,-3135a,-328-3p,and-500a-5p in blood plasma and miR-151a-3p,-181b-5p,-320a,-328,-433,-489,-572,-663a,-101-3p,-106b-5p,-19b-3p,-195-5p,and-130a-3p in blood serum of children,and miR-15b-5p and-6126 in whole blood of *** important limitations were identified in the studies reviewed,and need to be taken into account in future *** studies are warranted with children and adults having different levels of autism spectrum disorder severity and consideration should be given to using animal models of autism spectrum disorder to investigate the effects of suppressing or overexpressing specific microRNAs as a novel therapy.

关键词： autism spectrum disorder biomarker blood cells blood plasma blood serum diagnosis microRNA peripheral blood mononuclear cells serum neural cell adhesion molecule L1-captured extracellular vesicles whole blood

MicroRNAs as potential diagnostic biomarkers for bipolar disorder

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Neural Regeneration Research 2025年第6期20卷 1681-1695页

Abnormal expression of microRNAs is connected to brain development and disease and could provide novel biomarkers for the diagnosis and prognosis of bipolar disorder. We performed a PubMed search for microRNA biomarkers in bipolar disorder and found 18 original research articles on studies performed with human patients and published from January 2011 to June 2023. These studies included microRNA profiling in bloodand brain-based materials. From the studies that had validated the preliminary findings,potential candidate biomarkers for bipolar disorder in adults could be miR-140-3p,-30d-5p,-330-5p,-378a-5p,-21-3p,-330-3p,-345-5p in whole blood, miR-19b-3p,-1180-3p,-125a-5p, let-7e-5p in blood plasma, and miR-7-5p,-23b-5p,-142-3p,-221-5p,-370-3p in the blood serum. Two of the studies had investigated the changes in microRNA expression of patients with bipolar disorder receiving treatment. One showed a significant increase in plasma miR-134 compared to baseline after 4 weeks of treatment which included typical antipsychotics, atypical antipsychotics, and benzodiazepines. The other study had assessed the effects of prescribed medications which included neurotransmitter receptorsite binders(drug class B) and sedatives, hypnotics, anticonvulsants, and analgesics(drug class C) on microRNA results. The combined effects of the two drug classes increased the significance of the results for miR-219 and-29c with miR-30e-3p and-526b* acquiring significance. MicroRNAs were tested to see if they could serve as biomarkers of bipolar disorder at different clinical states of mania, depression, and euthymia. One study showed that upregulation in whole blood of miR-9-5p,-29a-3p,-106a-5p,-106b-5p,-107,-125a-3p,-125b-5p and of miR-107,-125a-3p occurred in manic and euthymic patients compared to controls, respectively, and that upregulation of miR-106a-5p,-107 was found for manic compared to euthymic patients. In two other studies using blood plasma,downregulation of miR-134 was observed i

关键词： biomarker bipolar disorder blood leukocytes blood plasma blood plasma extracellular vesicles/exosomes blood serum brain tissue brain tissue extracellular vesicles/exosomes lymphoblastoid cell lines microRNA neural progenitor cells whole blood

MicroRNAs as potential biomarkers for diagnosis of post-traumatic stress disorder

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Neural Regeneration Research 2025年第7期20卷 1957-1970页

Post-traumatic stress disorder is a mental disorder caused by exposure to severe traumatic life ***,there are no validated biomarkers or laboratory tests that can distinguish between trauma survivors with and without post-traumatic stress *** addition,the heterogeneity of clinical presentations of post-traumatic stress disorder and the overlap of symptoms with other conditions can lead to misdiagnosis and inappropriate *** suggests that this condition is a multisystem disorder that affects many biological systems,raising the possibility that peripheral markers of disease may be used to diagnose post-traumatic stress *** performed a PubMed search for microRNAs(miRNAs)in post-traumatic stress disorder(PTSD)that could serve as diagnostic biomarkers and found 18 original research articles on studies performed with human patients and published January 2012 to December *** included four studies with whole blood,seven with peripheral blood mononuclear cells,four with plasma extracellular vesicles/exosomes,and one with serum *** of these studies had also used whole *** studies were excluded as they did not involve microRNA *** of the studies had collected samples from adult male veterans who had returned from deployment and been exposed to combat,and only two were from recently traumatized adult *** measuring miRNA expression levels,many of the studies had used microarray miRNA analysis,miRNA Seq analysis,or NanoString *** six studies had used real time polymerase chain reaction assay to determine/validate miRNA expression in PTSD subjects compared to *** miRNAs that were found/validated in these studies may be considered as potential candidate biomarkers for PTSD and include miR-3130-5p in whole blood;miR-193a-5p,-7113-5p,-125a,-181c,and-671-5p in peripheral blood mononuclear cells;miR-10b-5p,-203a-3p,-4488,-502-3p,-874-3p,-5100,and-7641 in plasma extracellular vesicles/

关键词： biomarker diagnosis microRNA peripheral blood mononuclear cells plasma extracellular vesicles/exosomes post-traumatic stress disorder serum exosomes whole blood whole plasma

Microbial aspects of acid mine drainage and its bioremediation

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中国有色金属学会会刊：英文版 2008年第6期18卷 1352-1360页

作者： K.A.natarajan Department of Materials Engineering Indian Institute of Science

象从一些被孤立的 Acidithiobacillus ferrooxidans， Acidithiobacillus thiooxidans 和 Leptospirillum ferrooxidans 那样的 chemolithotrophs 的角色放弃了矿并且在酸矿排水和有毒的金属溶解的产生处理了废物跟踪被讨论。酸形成和从铜，铅锌和忍受毒砂的硫化物矿石和跟踪的铜，锌，铁和砷的溶解的机制面对细菌的 Acidithiobacillus 组被建立。从上述矿地点孤立的硫酸盐减少细菌(SRB ) 能被用来猛抛溶解金属象铜，锌，铁和砷那样。砷 bioremediation 通过本国的微生物的使用被表明如此的 Thiomonas spp。它能氧化亚砷酸盐到砷酸盐。通过 jarosite 的使用的砷的 Bioremoval 猛抛由 Acidithiobacillus ferrooxidans 产生了， Leptospirillum ferrooxidans 也被发现很有效。Biotechnological 过程在酸矿排水和象铜，锌和砷那样的有毒的金属离子的有效移动的补习保持大诺言。

关键词：酸矿排水生物治疗砷含量硫酸盐硫化物沉淀

High-temperature synthesis and electronic bonding analysis of Ca-doped LaMnO_(3) rare-earth manganites

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Rare Metals 2022年第11期41卷 3932-3942页

作者： natarajan Thenmozhi Ramachandran Saravanan Post Graduate and Research Department of Physics Nadar Mahajana Sangam S.Vellaichamy Nadar CollegeNagamalaiMaduraiTamil Nadu625019India Research Centre and Post Graduate Department of Physics The Madura CollegeMaduraiTamil Nadu625011India

Doped lanthanum manganites La_(1-x)Ca_(x)MnO_(3) with five different concentrations of Ca(x=0.1,0.2,0.3,0.4 and 0.5) were synthesized by high-temperature solidstate reaction method and *** prepared samples were experimentally analyzed by X-ray diffraction(XRD),ultraviolet-visible spectroscopy(Uv-vis),scanning electron microscopy/energy dispersive spectroscopy(SEM/EDS) and vibrating sample magnetometer(vSM)*** structure is confirmed for this compound from powder X-ray diffraction *** XRD data confirm the shrinkage in the unit cell of synthesized samples for increasing calcium *** Uv-visible analysis for the estimation of optical band gap(E_(g)) reveals that the band gap decreases with the incorporation of *** synthesized samples were investigated for charge density distribution using maximum entropy method,utilizing the XRD data *** the charge density analysis,it is found that the bond lengths for La-O and Mn-O bonds decrease with the addition of *** ionic nature between La and O atoms and covalent nature between Mn and O atoms are enhanced for 40% of *** 50% of Ca-doped sample,ionic nature between La and O atoms and covalent nature between Mn and O atoms *** the prepared samples exhibit ferromagnetism at 20 K and paramagnetism at 300 K.

关键词： Manganites Mixed valency Magnetocaloric Magnetoresistive SOFC

Unlocking hypoglycemia–associated brain microvascular dysfunction:critical insights from proteomic analysis

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Neural Regeneration Research 2025年第6期20卷 1707-1708页

作者： Siva S.v.P.Sakamuri Anil Sakamuri Department of Chemistry Auburn University at MontgomeryMontgomeryALUSA vascular Biology Center and Department of Medicine Medical College of Georgia at Augusta UniversityAugustaGAUSA

Hypoglycemia-a critical complication linked to worsened brain function in diabetic subjects:Hypoglycemia is characterized by a decline in circulatory glucose levels below sta nda rd physiological *** hypoglycemia,classified as level 1 hypoglycemia,is defined by blood glucose levels below 70 mg/dL and can be effectively addressed through carbohydrate *** hypoglycemia,denoted by blood glucose levels less than 54 mg/dL,poses a life-threatening risk if left *** with type 1 and type 2 diabetes undergoing insulin treatment are particularly susceptible to hypoglycemia due to impaired counterregulatory mechanisms.

关键词： impaired intake critical

Cortical hem signaling center: functions, development, and potential implications for evolution and brain disorders

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Neural Regeneration Research 2025年第4期20卷 1079-1080页

作者： victor v.Chizhikov Igor Y.Iskusnykh Department of Anatomy and Neurobiology University of Tennessee Health Science CenterMemphisTNUSA

Development of the telencephalon relies upon several signaling centers-localized cellular populations that supply secreted factors to pattern the cortical *** such signaling center is the cortical hem,which arises during embryonic development at the telencephalic dorsal midline,adjacent to the choroid plexus and hippocampal primordium(Figure 1A).While the cortical hem has also been described in reptiles and birds,most of our knowledge about the developmental roles of the cortical hem is derived from the analysis in *** cortical hem produces several types of secreted molecules,including wingless-related integration site(Wnt)and bone morphogenetic(Bmp)*** cortical hem is particularly important for the development of the hippocampus,which is involved in learning and memory,and the neocortex,which is the most complex brain region that mediates multiple types of behavior and higher cognitive functions(Mangale et al.,2008;Dal-valle-Anton and Borrell,2022).

关键词： epithelium Figure center