Stochastic spatio-temporal optimization for control and co-design of systems in robotics and applied physics

THE SPATIO-TEMPORAL VARIATIONS OF WIND SPEED DURING HARMATTAN SEASON IN NORTHEASTERN NIGERIA

Geosfera Indonesia ◽

10.19184/geosi.v4i2.11474 ◽

2019 ◽

Vol 4 (2) ◽

pp. 105

Author(s):

Dantata Danlami ◽

Saidu Idris ◽

Richard Sunday Thlakma ◽

Golly Sammy Gwandum

Keyword(s):

Wind Speed ◽

West Africa ◽

Temporal Variations ◽

West African ◽

Applied Physics ◽

Speed Distribution ◽

Wind Speed Distribution ◽

North Eastern ◽

Temporal And Spatial ◽

Spatio Temporal

Wind speed is the principal climatic element that drives the Marmaton season in West African sub region. It drives the season by conveying huge amount of dust across the Northeastern Nigeria. The presence of dust in the atmosphere brought by the Northeast trade winds during the Harmattan season plays a vital role in absorbing and scattering solar radiation. The study examines the spatial and temporal variations of wind speed in Northeastern Nigeria during the Harmattan season with the sole aim of ascertaining its variability, patterns and trends from1984 to 2014. Descriptive and statistics such as mean, standard deviation, coefficient of variation, and time series analysis with ArcGIS 10.3 was used in examine the temporal and spatial variations of wind speed from 1984–2014 in six synoptic stations of Northeastern Nigeria. The findings show that wind speed varied both temporally and spatially in the last three decades. The pattern of variations in the six synoptic stations shows rising trends within the study years. It was also found that latitude playing a crucial role in determining the speed of the wind in the study area and as the speed of the wind increases with increasing latitude. Keywords: Wind speed, Harmattan, Season, Northeast, Variation and ITD. References Adaramola,M.S.andOyewola,O. M. (2011). Wind Speed Distribution and Characteristics in Nigeria. Asian Research Publishing Network (ARPN). Journal of Engineering and Applied Sciences.ISSN 1819-6608.www.arpnjournals.com Amadi, S. O., Udo, S. O. and Ewona, I. O. (2014). Trends in Monthly Mean Minimum and Maximum Temperature Data over Nigeria for the Period 1950-2012. International Research Journal of Pure and Applied Physics, 2(4), 1-27. Ayoade, J.O. (2004). Introduction to Climatology for the Tropics.2nd ed. Spectrum Books Limitted, Spectrum House Ring Road Ibadan, Nigeria. Balarabe, M., Abdallah, K., and Nawawi, M. (2015). Long- Term Trend and Seasonal Variability of Horizontal Visibility in Nigerian Troposphere.Journal of Atmosphere 6:1462-1486; doi:10.3390/atmos6101462. Dahuwa, D., Promise, K. U., Umar, W., Bello, I. and Mohammed, R. (2018). Analysis of Wind Speed And Frequency InAzare North eastern Part of Nigeria. IOSR Journal of Applied Physics (IOSR-JAP) e-ISSN: 2278-4861.Volume 10, Issue 1 Ver. I. PP 09-17 www.iosrjournals.org DOI: 10.9790/4861-1001010917 www.iosrjournals.org Danlami, D., Gwari, M., Suleiman, S., and Bara, A. (2018). Temporal and Spatial variations of Groung Surface visibility during Harmattan Season in North-Eastern Nigeria.Ceylon Journal Science, 47(4), 337 – 346. DOI: http://doi.org/10.4038/cjs.v47i4.7551. Danlami, D. (2017). Spatio-Temporal Variations of Harmattan Season in Northeastern Nigeria.M.Sc. Dissertation (Not published) Submitted to the Department of Geography, Bayero University, Kano, Nigeria. De Longueville, F., Hountondji, Y. C., Henry, S. and Ozer, P. (2010). What do we Know about the Effects of Desert Dust on Air Quality and Human Health in West Africa compared to other regions? Journal: Science of Total Environment Fagbenle, R.L., Fasade, A.O., Amuludun A.K. andLala,P.O.( 1980). Wind power potentials of Nigeria. 12th Biennial conference of the West African Science Association, University of Ife, Nigeria. Getis, A., Getis, J., Bjelland, M. and Fellmann, J.D. (2011).Introduction to Geography. 13thed. The McGraw-Hill Companies, Inc., 1221 Avenue of the Americas, NY10020. Karabulut, M., Demirci, A. and Kora, F. (2012). Analysis of spatially distributed annual, seasonal and monthly temperatures in Istanbul from 1975 to 2006.World Applied Sciences Journal, 12(10), 1662-1675 Ojosu, J.O. and Salawu, R.I. (1990).An evaluation of wind energy potential as a power generation source in Nigeria.Solar & Wind Technology.ELSEVIER.Volume 7, Issue 6, 1990, Pages 663-673 Schwanghart, W. and Schutt, B. (2007). Meteorological causes of Harmattan dust in West Africa. Journal of Science Direct Geomorphology. Shuman, M. (2007) Evaluation of five GIS basedInterpolation techniques for estimating the Radonconcentration for unmeasured zip codes in thestate of Ohio, Master of Science Degree in Civil Engineering, University of Toledo, 28-29 Pp. Waewsak, J., Chancham, C., Landry, M. and Gagnon, Y (2011).An Analysis of Wind Speed Distribution at Thasala, Nakhon Si Thammarat, Thailand.Journal of Sustainable Energy & Environment 2 pp 51-55 Willmott, C., Robeson, S. and Philpot, W. (1985). Small- scale climate maps: A sensitivity analysisof some common assumptions associated withgrid-point interpolation and contouring. American Cartographer 12(1):5-16. Copyright (c) 2019 Geosfera Indonesia Journal and Department of Geography Education, University of Jember This work is licensed under a Creative Commons Attribution-Share A like 4.0 International License

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Electrostatic optics and aberration correction in the 1940s and today

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100120436 ◽

1992 ◽

Vol 50 (1) ◽

pp. 6-7

Author(s):

Gertrude F. Rempfer

Keyword(s):

Electron Microscope ◽

Focal Point ◽

Focal Length ◽

High Vacuum ◽

Electron Optics ◽

Applied Physics ◽

Electrostatic Lenses ◽

Commercial Instrument ◽

The University ◽

Theory And Experiment

I became involved in electron optics in early 1945, when my husband Robert and I were hired by the Farrand Optical Company. My husband had a mathematics Ph.D.; my degree was in physics. My main responsibilities were connected with the development of an electrostatic electron microscope. Fortunately, my thesis research on thermionic and field emission, in the late 1930s under the direction of Professor Joseph E. Henderson at the University of Washington, provided a foundation for dealing with electron beams, high vacuum, and high voltage.At the Farrand Company my co-workers and I used an electron-optical bench to carry out an extensive series of tests on three-electrode electrostatic lenses, as a function of geometrical and voltage parameters. Our studies enabled us to select optimum designs for the lenses in the electron microscope. We early on discovered that, in general, electron lenses are not “thin” lenses, and that aberrations of focal point and aberrations of focal length are not the same. I found electron optics to be an intriguing blend of theory and experiment. A laboratory version of the electron microscope was built and tested, and a report was given at the December 1947 EMSA meeting. The micrograph in fig. 1 is one of several which were presented at the meeting. This micrograph also appeared on the cover of the January 1949 issue of Journal of Applied Physics. These were exciting times in electron microscopy; it seemed that almost everything that happened was new. Our opportunities to publish were limited to patents because Mr. Farrand envisaged a commercial instrument. Regrettably, a commercial version of our laboratory microscope was not produced.

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E3 ubiquitin ligases

Essays in Biochemistry ◽

10.1042/bse0410015 ◽

2005 ◽

Vol 41 ◽

pp. 15-30 ◽

Cited By ~ 123

Author(s):

Helen C. Ardley ◽

Philip A. Robinson

Keyword(s):

Protein Complexes ◽

Loss Of Function ◽

Direct Role ◽

Cellular Processes ◽

Substrate Protein ◽

Protein Ubiquitination ◽

C Terminus ◽

Full Complement ◽

Spatio Temporal ◽

Eukaryotic Organisms

The selectivity of the ubiquitin–26 S proteasome system (UPS) for a particular substrate protein relies on the interaction between a ubiquitin-conjugating enzyme (E2, of which a cell contains relatively few) and a ubiquitin–protein ligase (E3, of which there are possibly hundreds). Post-translational modifications of the protein substrate, such as phosphorylation or hydroxylation, are often required prior to its selection. In this way, the precise spatio-temporal targeting and degradation of a given substrate can be achieved. The E3s are a large, diverse group of proteins, characterized by one of several defining motifs. These include a HECT (homologous to E6-associated protein C-terminus), RING (really interesting new gene) or U-box (a modified RING motif without the full complement of Zn2+-binding ligands) domain. Whereas HECT E3s have a direct role in catalysis during ubiquitination, RING and U-box E3s facilitate protein ubiquitination. These latter two E3 types act as adaptor-like molecules. They bring an E2 and a substrate into sufficiently close proximity to promote the substrate's ubiquitination. Although many RING-type E3s, such as MDM2 (murine double minute clone 2 oncoprotein) and c-Cbl, can apparently act alone, others are found as components of much larger multi-protein complexes, such as the anaphase-promoting complex. Taken together, these multifaceted properties and interactions enable E3s to provide a powerful, and specific, mechanism for protein clearance within all cells of eukaryotic organisms. The importance of E3s is highlighted by the number of normal cellular processes they regulate, and the number of diseases associated with their loss of function or inappropriate targeting.

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Elucidating cyclic AMP signaling in subcellular domains with optogenetic tools and fluorescent biosensors

Biochemical Society Transactions ◽

10.1042/bst20190246 ◽

2019 ◽

Vol 47 (6) ◽

pp. 1733-1747 ◽

Cited By ~ 3

Author(s):

Christina Klausen ◽

Fabian Kaiser ◽

Birthe Stüven ◽

Jan N. Hansen ◽

Dagmar Wachten

Keyword(s):

Cyclic Amp ◽

Adenosine Monophosphate ◽

Adenylyl Cyclases ◽

Temporal Precision ◽

Fluorescent Biosensors ◽

Subcellular Domains ◽

Spatio Temporal ◽

Hydrolysis Of ◽

Shed Light ◽

Cyclic Amp Signaling

The second messenger 3′,5′-cyclic nucleoside adenosine monophosphate (cAMP) plays a key role in signal transduction across prokaryotes and eukaryotes. Cyclic AMP signaling is compartmentalized into microdomains to fulfil specific functions. To define the function of cAMP within these microdomains, signaling needs to be analyzed with spatio-temporal precision. To this end, optogenetic approaches and genetically encoded fluorescent biosensors are particularly well suited. Synthesis and hydrolysis of cAMP can be directly manipulated by photoactivated adenylyl cyclases (PACs) and light-regulated phosphodiesterases (PDEs), respectively. In addition, many biosensors have been designed to spatially and temporarily resolve cAMP dynamics in the cell. This review provides an overview about optogenetic tools and biosensors to shed light on the subcellular organization of cAMP signaling.

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