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What can imaging tell us about cognitive impairment and dementia?

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World Journal of Radiology 2016年第3期8卷 240-254页

作者： leela narayanan Alison Dorothy Murray Department of Clinical Radiology NHS Grampian Health Board NHS Foresterhill Health Site Aberdeen Biomedical Imaging Centre Division of Applied Medicine University of Aberdeen Aberdeen Biomedical Imaging Centre Division of Applied Medicine School of Medicine University of Aberdeen

Dementia is a contemporary global health issue with far reaching consequences, not only for affected individuals and their families, but for national and global socio-economic conditions. the hallmark feature of dementia is that of irreversible cognitive decline, usually affecting memory, and impaired activities of daily living. Advances in healthcare worldwide have facilitated longer life spans, increasing the risks of developing cognitive decline and dementia in late life. Dementia remains a clinical diagnosis. the role of structural and molecular neuroimaging in patients with dementia is primarily supportive role rather than diagnostic, American and European guidelines recommending imaging to exclude treatable causes of dementia, such as tumor, hydrocephalus or intracranial haemorrhage, but also to distinguish between different dementia subtypes, the commonest of which is Alzheimer’s disease. However, this depends on the availability of these imaging techniques at individual centres. Advanced magnetic resonance imaging (MRI) techniques, such as functional connectivity MRI, diffusion tensor imaging and magnetic resonance spectroscopy, and molecular imaging techniques, such as 18F fluoro-deoxy glucose positron emission tomography (PEt), amyloid PEt, tau PEt, are currently within the realm of dementia research but are available for clinical use. Increasingly the research focus is on earlier identification of at risk preclinical individuals, for example due to family history. Intervention at the preclinical stages before irreversible brain damage occurs is currently the best hope of reducing the impact of dementia.

关键词： Dementia Alzheimer’s disease Magnetic resonance imaging Molecular imaging Frontotemporal dementia Lewy body dementia Vascular dementia

Frequency regularization of a linked wind- diesel system using dual structure fuzzy with ultra-capacitor

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Protection and Control of Modern Power Systems 2022年第1期7卷 165-173页

作者： Gulshan Sharma K.narayanan t.Adefarati Sachin Sharma Department of Electrical Engineering technology University of JohannesburgJohannesburg 2006South Africa Department of Electrical and Elec-tronics Engineering SASTRA DEEMED UNIVERSITYThanjavurIndia Department of Electrical and Electronic Engineering Federal University Oye EkitiOye EkitiNigeria Department of Electrical Engineering Graphic Era(Deemed to be University)DehradunIndia

Microgrids(μ-grids)are gaining increased interest around the world for supplying cheap and clean *** this paper,aμ-grid comprising a wind turbine generator(WtG)and diesel generator(DG)is *** is one of most practical and demanding systems suitable for the present energy crisis in isolated or rural ***,wind energy is intermittent in nature while load demand changes ***,aμ-grid can experience large frequency and power *** speed governor of the DG tries to minimize the frequency and power deviations inμ-grid though its operation is slow and cannot adequately minimize system *** paper proposes a novel arrangement based on a dual structured fuzzy(DSF)whose structure changes according to the switching limit with a reduced rule *** has the capability to switch between proportional and integral actions and hence improves the frequency regularization of theμ-*** proposed strategy is tested in aμ-grid and the results considering step load alteration,load alteration at different instants of time,nonstop changing load request are compared with some of the well published methods to validate the effectiveness and simplicity of the present *** addition,it shows that ultra-capacitor establishment in aμ-grid has a positive impact in minimizing system deviations with DSF for the studied cases.

关键词： Microgrid Wind generation Diesel generation Frequency control Dual mode fuzzy

Design of internal model control based fractional order PID controller

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控制理论与应用（英文版） 2012年第3期10卷 297-302页

作者： t.VINOPRABA N.SIVAKUMARAN S.narayanan t.K.RADHAKRISHNAN Department of Instrumentation and Control Engineering National Institute of TechnologyTiruchirappalli 620015India Department of Chemical Engineering National Institute of TechnologyTiruchirappalli 620015India

this article presents a design of the internal model control （IMC） based single degree of freedom （SDF） fractional order （FO） PID controller with a desired bandwidth specification for a class of fractional order system （FOS）. the drawbacks of the SDF FO-IMC are eliminated with the help of the two-degree of freedom （tDF） FO PID controller. the robust stability and robust performance of the designed controller are analyzed using an example.

关键词： Fractional order PID controller Fractional order systems Model based control Robust control

Life threatening vitamin B_(12) deficiency:will timely screening make a difference?

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World Journal of Gastroenterology 2000年第3期6卷 456-457页

作者： t.S.Dharmarajan S. Lakshmi narayanan Rajiv D. Poduval Chief Division of GeriatricsDirectorGeriatric Medicine Fellowship Program Our Lady of Mercy University Medical Center600 E 233~(rd)StreetBronxNY 10466 Resident Internal Medicine Our Lady of Mercy Medical Center Chief Medical Resident Internal Medicine Our Lady of Mercy Medical Center

INtRODUCtION While Vit.B12 deficiency is common,with aprevalence of about 15% in the elderly,andrecommendations for treatment available,detectionof deficiency at the pre-clinical stage by appropriatescreening does not always take *** report isan example of life threatening Vit.B12 deficiencydiagnosed at age 56,with the onset of Vit.B12depletion likely to have begun in the

关键词： vitamin B12 deficiency/therapy anemia sickle cell gastric mucosa biopsy anemia pernicious toxicity

Androgen receptor deficiency in monocytes/ macrophages does not alter adiposity or glucose homeostasis in male mice

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Asian Journal of Andrology 2018年第3期20卷 276-283页

作者： Katya B Rubinow Barbara Houston Shari Wang leela Goodspeed Kayoko Ogimoto Gregory J Morton Christopher McCarty Robert E Braun Stephanie t Page Division of Metabolism Endocrinology and Nutrition Department of Medicine University of Washington School of Medicine Seattle WA 98195 USA Jackson Laboratory Bar Harbor ME 04609 USA

Androgen deprivation in men leads to increased adiposity, but the mechanisms underlying androgen regulation of fat mass have not been fully defined. Androgen receptor （AR） is expressed in monocytes/macrophages, which are resident in key metabolic tissues and influence energy metabolism in surrounding cells. Male mice bearing a cell-specific knockout of the AR in monocytes/macrophages （M-ARKO） were generated to determine whether selective loss of androgen signaling in these cells would lead to altered body composition. Wild-type （Wt） and M-ARKO mice （12-22 weeks of age, n = 12 per group） were maintained on a regular chow diet for 8 weeks and then switched to a high-fat diet for 8 additional weeks. At baseline and on both the regular chow and high-fat diets, no differences in lean mass or fat mass were observed between groups. Consistent with the absence of differential body weight or adiposity, no differences in food intake （3.0 ± 0.5 g per day for Wt mice vs 2.8 ± 0.4 g per day for M-ARKO mice） or total energy expenditure （0.6 ± 0.1 Kcal h-1 for Wt mice vs 0.5 ± 0.1 Kcal h-1 for M-ARKO mice） were evident between groups during high-fat feeding. Liver weight was greater in M-ARKO than that in Wt mice （1.5 ± 0.1 g vs 1.3 ± 0.0 g, respectively, P = 0.02）. Finally, M-ARKO mice did not exhibit impairments in glucose tolerance or insulin sensitivity relative to Wt mice at any study time point. In aggregate, these findings suggest that AR signaling specifically in monocytes/macrophages does not contribute to the regulation of systemic energy balance, adiposity, or insulin sensitivity in male mice.

关键词： androgen receptor knockout mice macrophages male hypogonadism metabolic syndrome

Molecular therapeutics in pancreas cancer

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World Journal of Gastrointestinal Oncology 2016年第4期8卷 366-379页

作者： Vignesh narayanan Colin D Weekes Division of Medical Oncology Department of Medicine Developmental Therapeutics Program University of Colorado Cancer Center University of Colorado School of Medicine

the emergence of the "precision-medicine" paradigm in oncology has ushered in tremendous improvements in patient outcomes in a wide variety of malignancies. However, pancreas ductal adenocarcinoma(PDAC) has remained an obstinate challenge to the oncology community and continues to be associated with a dismal prognosis with 5-year survival rates consistently less than 5%. Cytotoxic chemotherapy with gemcitabine-based regimens has been the cornerstone of treatment in PDAC especially because most patients present with inoperable disease. But in recent years remarkable basic science research has improved our understanding of the molecular and genetic basis of PDAC. Whole genomic analysis has exemplified the genetic heterogeneity of pancreas cancer and has led to ingenious efforts to target oncogenes and their downstream signaling cascades. Novel stromal depletion strategies have been devised based on our enhanced recognition of the complex architecture of the tumor stroma and the various mechanisms in the tumor microenvironment that sustain tumorigenesis. Immunotherapy using vaccines and immune checkpoint inhibitors has also risen to the forefront of therapeutic strategies against PDAC. Furthermore, adoptive t cell transfer and strategies to target epigenetic regulators are being explored with enthusiasm. this review will focus on the recent advances in molecularly targeted therapies in PDAC and offer future perspectives to tackle this lethal disease.

关键词： Pancreas neoplasm Vaccines targeted therapy Immunotherapy Kirsten rat sarcoma oncogene

Design of Low Power transmission Gate Based 9t SRAM Cell

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Computers, Materials & Continua 2022年第7期72卷 1309-1321页

作者： S.Rooban Moru leela Md.Zia Ur Rahman N.Subbulakshmi R.Manimegalai Department of Electronics and Communication Engineering Koneru Lakshmaiah Education FoundationVaddeswaramGunturAndhra Pradesh522502India Department of Electronics and Communication Engineering Francis Xavier Engineering CollegeTirunelveliTamil Nadu627003India Department of Computer Science and Engineering PSG Institute of Technology and Applied ResearchCoimbatoreTamil Nadu641062India

Considerable research has considered the design of low-power and high-speed *** integrated circuits with low-power consumption is an important issue due to the rapid growth of high-speed *** static random-access memory(SRAM)units are necessary components in fast mobile *** SRAM cells are more energyconsuming and with lower *** major constraints in SRAM cells are their reliability and low *** objectives of the proposed method are to provide a high read stability,low energy consumption,and better writing abilities.A transmission gate-based multi-threshold single-ended Schmitt trigger(St)9t SRAM cell in a bit-interleaving structure without a write-back scheme is ***,an St inverter with a single bit-line design is used to attain the high read stability.A negative assist technique is applied to alter the trip voltage of the single-ended St *** multithreshold complementary metal oxide semiconductor(MtCMOS)technique is adopted to reduce the leakage power in the proposed single-ended tGSt 9t SRAM *** proposed system uses a combination of standard and St inverters,which results in a large read *** with the previous St 9t,St 11t,11t,10t,and 7t SRAM cells,the proposed cell is implemented in Cadence Virtuoso ADE with 45-nm CMOS technology and consumes 35.80%,42.09%,31.60%,12.54%,and 31.60%less energy for read operations and 73.59%,93.95%,92.76%,89.23%,and 85.78%less energy for write operations,respectively.

关键词： Bit-interleaving low power SRAM cell schmitt trigger transmission gate

On the Growth Mechanism of Nickel and Cobalt Nanowires and Comparison of their Magnetic Properties

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Nano Research 2008年第6期1卷 465-473页

作者： t.N.narayanan M.M.Shaijumon Lijie Ci P.M.Ajayan M.R.Anantharaman Department of Physics Cochin University of Science&TechnologyCochin-22KeralaIndia Department of Mechanical Engineering&Materials Science Rice UniversityHoustonTX 77005USA

Magnetic nanowires(NWs)are ideal materials for the fabrication of various multifunctional nanostructures which can be manipulated by an external magnetic fi *** crystalline and textured nanowires of nickel(Ni NWs)and cobalt(Co NWs)with high aspect ratio(~330)and high coercivity have been synthesized by electrodeposition using nickel sulphate hexahydrate(NiSO_(4)·6H_(2)O)and cobalt sulphate heptahydrate(CoSO_(4)·7H_(2)O)respectively on nanoporous alumina *** exhibit a preferential growth along〈110〉.A general mobility assisted growth mechanism for the formation of Ni and Co NWs is *** role of the hydration layer on the resulting one-dimensional geometry in the case of potentiostatic electrodeposition is verified.A very high interwire interaction resulting from magnetostatic dipolar interactions between the nanowires is *** unusual low-temperature magnetisation switching for fi eld parallel to the wire axis is evident from the peculiar high fi eld M(t)curve.

关键词： Magnetic nanowires mobility assisted growth magnetostatic interaction electrodeposition magnetisation switching

Effect of surface mechanical attrition treatment of titanium using alumina balls： surface roughness, contact angle and apatite forming ability

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Frontiers of Materials Science 2013年第3期7卷 285-294页

作者： M. JAMESH t. S. N. SANKARA narayanan Paul K. CHU II Song PARK Min Ho LEE National Metallurgical Laboratory Madras Centre CSIR Madras Complex Taramani Chennai 600 113 India Department of Physics and Material Science City University of Hong Kong Tat Chee Avenue Kowloon Hong Kong China School of Physics University of Sydney NSW 2006 Australia Department of Dental Biomaterials School of Dentistry Chonbuk National University Jeonju 561-756 South Korea

the effect of surface mechanical attrition treatment （SMAt） of commercially pure titanium （CP-ti） using 8 mm O alumina balls was studied. SMAt induced plastic deformation, increased the surface roughness, reduced the grain size and decreased the contact angle （from 64° to 43°） with a corresponding increase in surface energy （from 32 to 53 mJ/m2）. Untreated CP-ti and those treateded using alumina bails for 900 s reveals no apatite growth until the 28th day of immersion whereas those treated for 1800 and 2700 s exhibit apatite growth In selective areas and the extent of growth is increased with increase in immersion time an SBF; the study reveals that SMAt using alumina balls is beneficial in imparting the desired surface Cheracteristics, provided the surface contamination is limited, which would otherwise decrease the apatite forming ability.

关键词： KEYWORDS: nanostructured material surface modification sca.ning electron micro-scopy (SEM) surface mechanical attrition treatment(SMAt)