Graphical evaluation of complexometric titration curves.
Guinon, J L
1985-04-01
A graphical method, based on logarithmic concentration diagrams, for construction, without any calculations, of complexometric titration curves is examined. The titration curves obtained for different kinds of unidentate, bidentate and quadridentate ligands clearly show why only chelating ligands are usually used in titrimetric analysis. The method has also been applied to two practical cases where unidentate ligands are used: (a) the complexometric determination of mercury(II) with halides and (b) the determination of cyanide with silver, which involves both a complexation and a precipitation system; for this purpose construction of the diagrams for the HgCl(2)/HgCl(+)/Hg(2+) and Ag(CN)(2)(-)/AgCN/CN(-) systems is considered in detail.
Complexometric Determination of Mercury Based on a Selective Masking Reaction
ERIC Educational Resources Information Center
Romero, Mercedes; Guidi, Veronica; Ibarrolaza, Agustin; Castells, Cecilia
2009-01-01
In the first analytical chemistry course, students are introduced to the concepts of equilibrium in water solutions and classical (non-instrumental) analytical methods. Our teaching experience shows that "real samples" stimulate students' enthusiasm for the laboratory work. From this diagnostic, we implemented an optional activity at the end of…
ERIC Educational Resources Information Center
Smith, Garon C.; Hossain, Md Mainul
2017-01-01
"Complexation TOPOS" is a free software package to generate 3-D topographic surfaces ("topos") for metal-ligand complexometric titrations in aqueous media. It constructs surfaces by plotting computed equilibrium parameters above a composition grid with "volume of ligand added" as the x-axis and overall system dilution…
ERIC Educational Resources Information Center
Garvey, Sarah L.; Shahmohammadi, Golbon; McLain, Derek R.; Dietz, Mark L.
2015-01-01
A laboratory experiment is described in which students compare two methods for the determination of the calcium content of commercial dietary supplement tablets. In a two-week sequence, the sample tablets are first analyzed via complexometric titration with ethylenediaminetetraacetic acid and then, following ion exchange of the calcium ion present…
Kovács, G. S.; Tárnoky, K. E.
1960-01-01
A simple and rapid procedure has been developed for the complexometric titration of serum calcium and magnesium using “plasmocorinth B” as indicator. Both determinations can be carried out from the same 0.5 ml. sample. The method is in good agreement with the established calcium and magnesium methods. PMID:14411396
Mishra, Arti; Bhalla, Sumir Rai; Rawat, Sameera; Bansal, Vivek; Sehgal, Rakesh; Kumar, Sunil
2007-10-01
In the present study, Aluminium quantification in immunobiologicals has been described using atomic absorption spectroscopy (AAS) technique. The assay was found to be linear in 25-125 microg/ml Aluminium range. The procedure was found to be accurate for different vaccines with recoveries of external additions ranging between 93.26 and 103.41%. The mean Limit of Variation (L.V.) for both intra- and inter-assay precision was calculated to be 1.62 and 2.22%, respectively. Further the procedure was found to be robust in relation to digestion temperature, alteration in acid (HNO(3) and H(2)SO(4)) ratio used for sample digestion and storage of digested vaccine samples up to a period of 15 days. After validation, AAS method was compared for its equivalency with routinely used complexometric titration method. On simultaneously applying on seven different groups of both bacterial and viral vaccines, viz., DPT, DT, TT, Hepatitis-A and B, Antirabies vaccine (cell culture) and tetravalent DPT-Hib, a high degree of positive correlation (+0.85-0.998) among AAS and titration methods was observed. Further AAS method was found to have an edge over complexometric titration method that a group of vaccines, viz., ARV (cell culture, adsorbed) and Hepatitis-A, in which Aluminium estimation is not feasible by pharmacopoeial approved complexometric titration method (possibly due to some interference in the sample matrix), this newly described and validated AAS assay procedure delivered accurate and reproducible results.
Stepwise Inquiry into Hard Water in a High School Chemistry Laboratory
ERIC Educational Resources Information Center
Kakisako, Mami; Nishikawa, Kazuyuki; Nakano, Masayoshi; Harada, Kana S.; Tatsuoka, Tomoyuki; Koga, Nobuyoshi
2016-01-01
This study focuses on the design of a learning program to introduce complexometric titration as a method for determining water hardness in a high school chemistry laboratory. Students are introduced to the different properties and reactions of hard water in a stepwise manner so that they gain the necessary chemical knowledge and conceptual…
Hafez, M A; Khalifa, M E
1997-05-01
A rapid and simple general complexometric method was presented for the determination of lead, cadmium and thallium or mercury or arsenic(V) in laboratory synthesized mixtures similar to those of some ores, minerals and alloys of such metals. The precision and accuracy attainable in successive titrations of Pb(2+), Cd(2+) and Tl(3+) or Hg(2+) or AsO(3-)(4) (As(5+)) with 0.05 and/or 0.01 mol 1(-1) solutions of disodium ethylenediaminetetraacetate (Na(2)EDTA) and standard Pb(NO(3))(2) of the same concentration using Bromo-Cresol Orange (BCO) as a new metallochromic indicator with visual endpoint indication were studied. For the analysis of a three component mixtures of the aforementioned ions, Tl(3+) was at first directly titrated with Na(2)EDTA at pH 0.5-1 (HNO(3)) using BCO as indicator. At the thallium endpoint an excess of Na(2)EDTA was added and the pH was adjusted at pH approximately 4.8 using hexamine-HNO(3) buffer (solution A). The excess EDTA was back-titrated with standard solution of Pb(NO(3))(2). 1,10-Phenanthroline (1,10-phen) was added to release the EDTA combined with Cd(2+), while thiosemicarbazide (TSC) was used to liberate the EDTA from the mercury-EDTA chelate. To determine AsO(3-)(4) ion in such type of mixtures the pH of (solution A) was raised to a value of 10 using ammonia buffer. Excess standard Mg(2+) solution was added and the formed precipitate of MgNH(4)AsO(4) was separated, dissolved and its magnesium content equivalent to AsO(3-)(4) was determined complexometrically using Eriochrome Black-T (EBT) indicator. The interference caused by different anions, cations and organic acids was investigated. A comparison of the indicators BCO and Xylenol Orange (XO) for successive titration of the studied metal ions was carried out. The proposed successive titration method was applied successfully to some real samples of ores, minerals and alloys of the studied metal ions and the results were satisfactory and agreed with those obtained by AAS.
Validated flow-injection method for rapid aluminium determination in anti-perspirants.
López-Gonzálvez, A; Ruiz, M A; Barbas, C
2008-09-29
A flow-injection (FI) method for the rapid determination of aluminium in anti-perspirants has been developed. The method is based on the spectrophotometric detection at 535nm of the complex formed between Al ions and the chromogenic reagent eriochrome cyanine R. Both the batch and FI methods were validated by checking the parameters included in the ISO-3543-1 regulation. Variables involved in the FI method were optimized by using appropriate statistical tools. The method does not exhibit interference from other substances present in anti-perspirants and it shows a high precision with a R.S.D. value (n=6) of 0.9%. Moreover, the accuracy of the method was evaluated by comparison with a back complexometric titration method, which is currently used for routine analysis in pharmaceutical laboratories. The Student's t-test showed that the results obtained by both methods were not significantly different for a significance level of 95%. A response time of 12s and a sample analysis time, by performing triplicate injections, of 60s were achieved. The analytical figures of merit make the method highly appropriate to substitute the time-consuming complexometric method for this kind of analysis.
Signal processing with a summing operational amplifier in multicomponent potentiometric titrations.
Parczewski, A
1987-06-01
It has been proved that application of two indicator electrodes connected to the ordinary titration apparatus through an auxiliary electronic device (a summing operational amplifier) significantly extends the scope of multicomponent potentiometric titrations in which the analytes are determined simultaneously from a single titration curve. For each analyte there is a corresponding potential jump on the titration curve. By application of the proposed auxiliary device, the sum of the electrode potentials is measured. The device also enables the relative sizes of the potential jumps at the end-points on the titration curve to be varied. The advantages of the proposed signal processing are exemplified by complexometric potentiometric titrations of Fe(III) and Cu(II) in mixtures, with a platinum electrode and a copper ion-selective electrode as the indicator electrodes.
Polyether precursors of molecular recognition systems based on the 9,10-anthraquinone moiety
NASA Astrophysics Data System (ADS)
Wcisło, Anna; Cirocka, Anna; Zarzeczańska, Dorota; Niedziałkowski, Paweł; Nakonieczna, Sandra; Ossowski, Tadeusz
2015-02-01
A series of novel polyether derivatives of 9,10-anthraquinone (AQ) was synthesized and characterized by means of UV-Vis spectroscopy, acid-base titration and complexometric titration. The results were compared with 1-NEt2AQ and 1-NHEtAQ - model compounds of alkylaminoanthraquinones. Acetonitrile and methanol were used as solvents for determination of spectroscopic and acid-base properties. Complexometric titrations were carried out exclusively in acetonitrile. Spectral characteristic of these compounds strongly depends on pH. Addition of acid causes the decrease of absorption intensity and in some cases also a shift of the visible range band. The weakest base is the compound (2), and the strongest - compound (1), both in methanol and acetonitrile solution. The introduction of an additional substituent in the position 8 of the anthraquinone compound increases its basicity. The presence of metal ions causes changes in intensity of absorption (decrease for compounds (2) and (3) and increase with bathochromic shift for (1) and (4)). For the determination of the coordination properties aluminum (III) ions were chosen. The highest complex stability constant with Al (III) ions is observed for compound (1), and the weakest for compound (3). The elongation of the polyether chain decreases the stability of the complex formed.
Polyether precursors of molecular recognition systems based on the 9,10-anthraquinone moiety.
Wcisło, Anna; Cirocka, Anna; Zarzeczańska, Dorota; Niedziałkowski, Paweł; Nakonieczna, Sandra; Ossowski, Tadeusz
2015-02-25
A series of novel polyether derivatives of 9,10-anthraquinone (AQ) was synthesized and characterized by means of UV-Vis spectroscopy, acid-base titration and complexometric titration. The results were compared with 1-NEt2AQ and 1-NHEtAQ--model compounds of alkylaminoanthraquinones. Acetonitrile and methanol were used as solvents for determination of spectroscopic and acid-base properties. Complexometric titrations were carried out exclusively in acetonitrile. Spectral characteristic of these compounds strongly depends on pH. Addition of acid causes the decrease of absorption intensity and in some cases also a shift of the visible range band. The weakest base is the compound (2), and the strongest--compound (1), both in methanol and acetonitrile solution. The introduction of an additional substituent in the position 8 of the anthraquinone compound increases its basicity. The presence of metal ions causes changes in intensity of absorption (decrease for compounds (2) and (3) and increase with bathochromic shift for (1) and (4)). For the determination of the coordination properties aluminum (III) ions were chosen. The highest complex stability constant with Al (III) ions is observed for compound (1), and the weakest for compound (3). The elongation of the polyether chain decreases the stability of the complex formed. Copyright © 2014 Elsevier B.V. All rights reserved.
NASA Technical Reports Server (NTRS)
Khristova, R.; Vanmen, M.
1986-01-01
Based on considerations of principles and experimental data, the interference of sulfate ions in poteniometric titration of EDTA with FeCl3 was confirmed. The method of back complexometric titration of molybdenum of Nonova and Gasheva was improved by replacing hydrazine sulfate with hydrazine hydrochloride for reduction of Mo(VI) to Mo(V). The method can be used for one to tenths of mg of molybdenum with 0.04 mg standard deviation. The specific method of determination of molybdenum in molybdenite concentrates is presented.
Safety study of intravitreal and suprachoroidal Laponite clay in rabbit eyes.
Prieto, Esther; Vispe, Eugenio; De Martino, Alba; Idoipe, Miriam; Rodrigo, María J; Garcia-Martin, Elena; Fraile, José M; Polo-Llorens, Vicente; Mayoral, José A
2018-03-01
To study the safety and biocompatibility of Laponite clay (LAP) within an intravitreal and suprachoroidal administration in rabbit eyes. Thirty-two New Zealand albino rabbits were divided into two experimental groups to test intravitreal (IVT group) and suprachoroidal (SCS group) administration of a 100-μl and 50-μl Laponite suspension respectively. Following injection, the eyes were monitored by ocular tonometry, slit-lamp eye examination and indirect ophthalmoscopy, at 24 h, 1, 4, 12, and 14 weeks post administration. Histological examination was also performed to determine whether any ocular pathological change had occurred. Throughout the study, LAP presence in vitreous was estimated by complexometric titration with ethylenediaminetetraacetic acid (EDTA), taking advantage of the Laponite high content of magnesium ions. Neither significant differences in the intraocular pressure, nor relevant ocular complications were found in the two experimental groups after LAP administration. The histology of the retina remained unchanged. LAP presence in vitreous could be indirectly confirmed by complexometric titration until 14 weeks post administration in eyes of IVT group. Laponite could be considered as a vehicle for potential clinical use in ocular drug administration, due to its proven ocular biocompatibility and its transparency in gel state.
Complexometric determination of gallium with calcein blue as indicator
Elsheimer, H.N.
1967-01-01
A metalfluorechromic indicator, Calcein Blue, has been used for the back-titration of milligram amounts of EDTA in presence of gallium complexes. The indicator was used in conjunction with an ultraviolet titration assembly equipped with a cadmium sulphide detector cell and a microammeter for enhanced end-point detection. The result is a convenient and rapid method with an accuracy approaching 0.1 % and a relative standard deviation of about 0.4% for 10 mg of gallium. ?? 1967.
Granholm, Kim; Sokalski, Tomasz; Lewenstam, Andrzej; Ivaska, Ari
2015-08-12
A new method to convert the potential of an ion-selective electrode to concentration or activity in potentiometric titration is proposed. The advantage of this method is that the electrode standard potential and the slope of the calibration curve do not have to be known. Instead two activities on the titration curve have to be estimated e.g. the starting activity before the titration begins and the activity at the end of the titration in the presence of large excess of titrant. This new method is beneficial when the analyte is in a complexed matrix or in a harsh environment which affects the properties of the electrode and the traditional calibration procedure with standard solutions cannot be used. The new method was implemented both in a method of linearization based on the Grans's plot and in determination of the stability constant of a complex and the concentration of the complexing ligand in the sample. The new method gave accurate results when using titrations data from experiments with samples of known composition and with real industrial harsh black liquor sample. A complexometric titration model was also developed. Copyright © 2015 Elsevier B.V. All rights reserved.
NASA Astrophysics Data System (ADS)
Weigand, Willis A.
2000-10-01
At Altoona College, Chemistry 11 is offered to students as a preparatory course for the University's Chemical Principles course, Chem 12. A relevant laboratory is a source of motivation for the students to learn the chemistry. One way of making the laboratory relevant is to analyze the chemical components of consumer products. Several new shower-cleaning products have been introduced, which advertise that cleaning the shower is no longer necessary. The cleaners work using a combination of surfactants, alcohols, and a chelating agent. The Web site of a popular shower cleaner lists EDTA (ethylenediamine tetraacetate ion) as the chelating agent. The classic EDTA/calcium complexometric titration can be used to determine the EDTA content of the cleaner. This article describes the experiment to determine the EDTA content in a shower-cleaning product.
Banerjee, S
1986-04-01
A sensitive spectrophotometric method for the determination of titanium by formation of its complex with tannin and thioglycollic acid at pH 4 has been developed. The intense yellow colour is measured at 400 nm and the system obeys Beer's law over the range 0.2-5 ppm titanium in the solution measured. The method is applicable to titanium-treated steels, stainless steels, permanent magnet alloys and duralumin alloys. The interference of Co, Ni, Cr, Mn, V, Mo and W can be eliminated by prior separation of titanium by controlled addition of cupferron in the presence of thioglycollic acid (TGA). Copper can be quantitatively separated by precipitation with TGA and determined complexometrically with EDTA, with PAN as indicator. Niobium interferes even in traces.
A Novel Ion - selective Polymeric Membrane Sensor for Determining Thallium(I) With High Selectivity
NASA Astrophysics Data System (ADS)
Kassim, Anuar; Rezayi, Majid; Ahmadzadeh, Saeid; Rounaghi, Gholamhossein; Mohajeri, Masoomeh; Azah Yusof, Noor; Tee, Tan Wee; Yook Heng, Lee; Halim Abdullah, Abd
2011-02-01
Thallium is a toxic metal that introduced into the environment mainly as a waste from the production of zinc, cadmium, and lead and by combustion of coal. Thallium causes gastrointestinal irritation and nerve damage when people are exposed to it for relatively short period of time. For long term, thallium has the potential to cause the following effects: change in blood chemistry, damage to liver, kidney, intestinal and testicular tissue, and hair loss. In this work a membrane was prepared by use of 4'-nitrobenzo -18-crown-6 (4'NB18C6) as an ion carrier, polyvinylchloride (PVC) as a matrix, and diocthylphetalate (DOP) as a plasticizer for making an ion selective electrode for measurement of Tl+ cation in solutions. The amount of 4'-nitrobenzo-18C6 and polyvinylchloride were optimized in the preparation of the membrane. The response of the electrode was Nernstian within the concentration range 1.0 × 10-8 to 1.0 × 10-1M. This sensor displays a drift in Nernstian response for this cation with increasing the amount of ionophore and decreasing the amount of polyvinylchloride.The results of potentiometric measurements showed that, this electrode also responses to Cu2+ Ni2+ and Pb2+ cations, but the electrode has a wider dynamic range and a lower detection limit to Tl+ cation. The effects of various parameters such as pH, different cations interferences, effect of the amount of ionophore and polyvinylchloride and time on response of the coated ion selective electrode were investigated. Finally the constructed electrode was used in complexometric and precipitation titrations of Tl+ cation with EDTA and KBr, respectively. The response of the fabricated electrode at concentration range from 1.0 × 10-8 to 1.0 × 10-1M is linear with a Nernstian slope of 57.27 mV.
Konopski, Leszek; Kiełczewska, Anna
2012-01-01
2-Trichloromethylbenzimidazole (TCMB) was used as a chromogenic reagent in organic or inorganic analysis, mainly in thin-layer chromatography (TLC). In reactions of TCMB with some heteroaromatic nitrogen containing compounds, such as azines, azoles and benzazoles, a formation of high colored products occurred. For azines, the chromogenic reaction was highly regioselective, since the both adjacent α-positions versus the nitrogen atom(s) must not be substituted. A TLC method of detection was developed. Thirty azines, azoles, and benzazoles were detected at the detection limit 10 ng to 1 μg. This method was also applied for detection of heteroaromatic pesticides, and the attempts to construct active and passive dosimeters for nicotine were made. In a prechromatographic reaction of aromatic o-diamines with methyl trichloroacetimidate, TCMB or its derivatives were formed in situ. Followed by TLC and visualization in pyridine vapors, this procedure was applied for detection of o-phenylenediamine derivatives. The reaction product of TCMB and pyridine (LI Complex) was identified and fully characterized. Two different reaction mechanisms: with electron deficient basic heteroaromatic compounds, like pyridine, and with more acidic compounds, for example, pyrrole, were discussed. In aqueous solutions, the LI Complex may be also used as a new indicator for complexometric, adsorption and acid-base titration of inorganic compounds. PMID:22567563
Vavrusova, Martina; Munk, Merete Bøgelund; Skibsted, Leif H
2013-08-28
Among the calcium hydroxycarboxylates important for cheese quality, D-lactobionate [Ksp = (7.0 ± 0.3) × 10(-3) mol(3) L(-3)] and L-lactate [Ksp = (5.8 ± 0.2) × 10(-3) mol(3) L(-3)] were found more soluble than D-gluconate [Ksp = (7.1 ± 0.2) × 10(-4) mol(3) L(-3)], as indicated by the solubility products determined electrochemically for aqueous 1.0 M NaCl at 25.0 °C. Still, solubility of calcium L-lactate increases by 45% in the presence of 0.50 M sodium D-gluconate and by 37% in the presence of 0.50 M sodium D-lactobionate, while solubility of calcium D-gluconate increases by 66 and 85% in the presence of 0.50 M sodium L-lactate and 0.50 M sodium D-lactobionate, respectively, as determined by complexometric titration. Sodium L-lactate and sodium D-gluconate have only little influence on solubility of calcium D-lactobionate. The increased solubility is described quantitatively by calcium binding to D-gluconate (K1 = 14 ± 3 mol(-1) L) in 1.0 M NaCl at 25 °C, D-lactobionate (K1 = 11 ± 2 mol(-1) L), and L-lactate (K1 = 8 ± 2 mol(-1) L), as indicated by the association constants determined electrochemically. In mixed hydroxycarboxylate solutions, calcium binding is quantitatively described by the geometric mean of the individual association constants for both aqueous 1.0 and 0.20 M NaCl, indicating a 1:1 stoichiometry for complex formation.
Composition and structure of acid leached LiMn 2-yTi yO 4 (0.2≤ y≤1.5) spinels
NASA Astrophysics Data System (ADS)
Avdeev, Georgi; Amarilla, José Manuel; Rojo, José María; Petrov, Kostadin; Rojas, Rosa María
2009-12-01
Lithium manganese titanium spinels, LiMn 2-yTi yO 4, (0.2≤ y≤1.5) have been synthesized by solid-state reaction between TiO 2 (anatase), Li 2CO 3 and MnCO 3. Li + was leached from the powdered reaction products by treatment in excess of 0.2 N HCl at 85 °C for 6 h, under reflux. The elemental composition of the acidic solution and solid residues of leaching has been determined by complexometric titration, atomic absorption spectroscopy and X-ray fluorescence analysis. Powder X-ray diffraction was used for structural characterization of the crystalline fraction of the solid residues. It has been found that the amount of Li + leached from LiMn 2-yTi yO 4 decreases monotonically with increasing y in the interval 0.2≤ y≤1.0 and abruptly drops to negligibly small values for y>1.0. The content of Mn and Li in the liquid phase and of Mn and Ti in the solid (amorphous plus crystalline) residue, were related to the composition and cation distribution in the pristine compounds. A new formal chemical equation describing the process of leaching and a mechanism of the structural transformation undergone by the initial solids as a result of Li + removal has been proposed.
Selective Extraction of Metals from Pacific Sea Nodules with Dissolved Sulfur Dioxide
NASA Astrophysics Data System (ADS)
Khalafalla, Sanaa E.; Pahlman, John E.
1981-08-01
How to tritrate a rock? … The following article illustrates the possibility of titrating a metallic constituent in a mineral with a selective reagent to an endpoint of near complete metal extraction. A very rapid and efficient—almost instantaneous and quantitative—method has been devised to differentially leach manganese, nickel, and cobalt to the exclusion of copper and iron from deep-sea nodules.1 In this method, a given weight of raw sea nodules ground to -200 mesh in an aqueous slurry is contacted for 10 min at room temperature and ambient pressure with a specified quantity of SO2. An independent leaching parameter R has been defined as the ratio of the number of moles of SO2 in the leaching solution to the weight of sea nodules. Variation of metal extraction with R generates sigmoidal curves characteristic of the metals extracted. A threshold value of R is required to initiate the leaching of a given metal from the mixed oxides. Once this threshold is reached, the metal recovery can rise above 95% in less than 10 minutes. For increasing value of R the extractability of various metals from Pacific sea nodules by SO2 follows the order: Mn > Ni > Co ≫ Fe, Al, Cu. Disparity in the R values permits a variety of selective leaching systems and metal separations simply by changing the quantity of SO2 in the contacting solution. Success in this leaching system depends on comminuting the nodules to less than 100 mesh. Above this critical size, leaching is slowed due to the inaccessibility of the inner particle reacting groups to the SO2 leaching agent, resulting in lower and nonselective extractions of preferred metal values. Leaching with HCl solutions of the same pH level as dissolved SO2 yielded mixed, slow, and incomplete metal extractions. This finding rules out any interpretation based on hydrogen ion from the ionization of sulfurous acid as the leaching agent. The leaching curves observed in the new system resemble the complexometric titration curves of heavy metals with specific coordination species.
NASA Astrophysics Data System (ADS)
Chandrasekhar, Anoop; Sander, Sylvia; Milnes, Angie; Boyd, Philip
2015-04-01
Iron plays a significant role in the ocean productivity as a micro nutrient that facilitates the growth of marine phytoplankton and microbes. The bioavailability of iron in the ocean depends on it speciation. Iron is bio available in its dissolved form and about 99.9% of dissolved iron in seawater is organically complexed with natural ligands. The competitive ligand equilibration - adsorptive cathodic stripping voltammetry (CLE-AdCSV) is the widely used technique to examine Fe speciation. The method has its own limitations. The analytical window employed in this technique has a distinct impact on Fe speciation results (Buck, Moffett et al. 2012). Recently, (Pizeta, Sander et al. in preparation) have shown that the accuracy of complexometric titrations improve if multiple analytical windows (MAW) are solved as a united dataset. Several programs are now available that enable this approach with the KMS (Kineteql.xls , Hudson 2014), which is based on an Excel application based on speciation calculation (Hudson, Rue et al. 2003, Sander, Hunter et al. 2011), being one of them. In the present work, the unified MAW data analysis method is applied to determine iron speciation by CLE-AdCSV with salicyl aldoxime (SA) (Abualhaija and van den Berg 2014) in real seawater samples from the Spring bloom FeCycle III voyage, which took place in an anticyclonic eddy in subtropical waters east of New Zealand in spring 2012. Two different analytical windows (5 and 15µM SA) were applied to samples from depth profiles taken during this cruise. The data obtained was analysed using the program KMS (Kineteql.xls). Most samples only returned one Fe-binding ligands class. Higher ligand concentrations were observed in the upper water column and the stability constants were above 22 (e.g. 22.25 ± 0.21 for station 63). Our results will be discussed in the context of microbial community distribution as well as other biogeochemical parameters. Abualhaija, M. M. and C. M. G. van den Berg (2014). "Chemical speciation of iron in seawater using catalytic cathodic stripping voltammetry with ligand competition against salicylaldoxime." Marine Chemistry 164(0): 60-74. Buck, K. N., J. Moffett, K. A. Barbeau, R. M. Bundy, Y. Kondo and J. Wu (2012). "The organic complexation of iron and copper: an intercomparison of competitive ligand exchange-adsorptive cathodic stripping voltammetry (CLE-ACSV) techniques " Limnology and Oceanography: Methods 10: 496-515. Hudson, R. J. M., E. L. Rue and K. W. Bruland (2003). "Modeling Complexometric Titrations of Natural Water Samples." Environ. Sci. Tech. 37: 1553-1562. Pizeta, I., S. G. Sander, O. Baars, K. Buck, R. Bundy, G. Carrasco, P. Croot, C. Garnier, L. Gerringa, M. Gledhill, K. Hirose, D. R. Hudson, Y. Kondo-Jacquot, L. Laglera, D. Omanovic, M. Rijkenberg, B. Twining and M. Wells (in preparation). "Intercomparison of estimating metal binding ligand parameters from simulated titration data using different fitting approaches." for Limnology and Oceanography: Methods. Sander, S. G., K. A. Hunter, H. Harms and M. Wells (2011). "Numerical approach to speciation and estimation of parameters used in modeling trace metal bioavailability." Environmental Science and Technology 45(15): 6388-6395.
Sionkowska, Alina; Kaczmarek, Beata
2017-09-01
3D porous composites based on the blend of chitosan, collagen and hyaluronic acid with the addition of nano-hydroxyapatite were prepared. SEM images for the composites were made and the structure was assessed. Mechanical properties were studied using a Zwick&Roell Testing Mashine. In addition, the porosity and density of composites were measured. The concentration of calcium ions released from the material was detected by the complexometric titration method. The results showed that in 3D porous sponge based on the blend of chitosan, collagen and hyaluronic acid, inorganic particles of nanohydroxyapatite can be incorporated, as well as that the properties of 3D composites depend on the material composition. Mechanical parameters and thermal stability of ternary biopolymeric blends were improved by the addition of hydroxyapatite. Moreover, the porosity of ternary materials was higher than in materials based on pure chitosan or collagen. All composites were characterized by a porous structure with interconnected pores. Calcium ions can be released from the composite during its degradation in water. Copyright © 2017 Elsevier B.V. All rights reserved.
NASA Astrophysics Data System (ADS)
Barabaś, Anna; Madura, Izabela D.; Marek, Paulina H.; Dąbrowska, Aleksandra M.
2017-11-01
The structure, conformation and configuration of the n-propyl 3-azido-2,3-dideoxy-β-D-arabino-hexopyranoside (BAra-nPr) were determined by 1H NMR, 13C NMR, and IR spectroscopy, as well as by optical rotation. The crystal structure was confirmed by single-crystal X-ray diffraction studies at room temperature. The compound crystallizes in P21 space group symmetry of the monoclinic system. The molecule has a 4C1 chair conformation with azide group in the equatorial position both in a solution as well as in the crystal. The spatial arrangement of azide group is compared to other previously determined azidosugars. The hydrogen bonds between the hydroxyl group of sugar molecules lead to a ribbon structure observed also for the ethyl homolog. The packing of ribbons is dependent on the alkyl substituent length and with the elongation changes from pseudohexagonal to lamellar. Acidity constants for the n-propyl 3-azido-2,3-dideoxy-β-D-arabino-hexopyranoside (BAra-nPr) in an aqueous solution were evaluated by the spectrophotometric and potentiometric titrations methods. Title compound exhibit blue absorption with the maximum wavelengths in the range of 266 nm and 306 nm. Based on these measurements we showed equilibria existing in a particular solution and a distribution of species which have formed during the titration. We also investigated interactions between Cu(II), Ni(II) and VO(II) and title compound (as ligand L) during complexometric titration. On these bases we identified that in [CuII-BAra-nPr]2+ the ratio of the ligand L to metal ion M(II) was 3:1, while in [NiII-BAra-nPr]2+ and [VOII-BAra-nPr]2+ complexes 2:1 ratios were found. The cumulative stability constants (as log β) occurring in an aqueous solution for the complexes of BAra-nPr with Cu(II), Ni(II) and VO(IV) were 14.57; 11.71 and 4.20, respectively.
Metal Doped Manganese Oxide Thin Films for Supercapacitor Application.
Tung, Mai Thanh; Thuy, Hoang Thi Bich; Hang, Le Thi Thu
2015-09-01
Co and Fe doped manganese oxide thin films were prepared by anodic deposition at current density of 50 mA cm(-2) using the electrolyte containing manganese sulfate and either cobalt sulfate or ferrous sulfate. Surface morphology and crystal structure of oxides were studied by scanning electron microscope (SEM) and X-ray diffraction (XRD). Chemical composition of materials was analyzed by X-ray energy dispersive spectroscope (EDS), iodometric titration method and complexometric titration method, respectively. Supercapacitive behavior of Co and Fe doped manganese oxide films were characterized by cyclic voltammetry (CV) and impedance spectroscopy (EIS). The results show that the doped manganese oxides are composed of nano fiber-like structure with radius of 5-20 nm and remain amorphous structure after heat treatment at 100 degrees C for 2 hours. The average valence of manganese increases from +3.808 to +3.867 after doping Co and from +3.808 to +3.846 after doping Fe. The doped manganese oxide film electrodes exhibited preferably ideal pseudo-capacitive behavior. The specific capacitance value of deposited manganese oxide reaches a maximum of 175.3 F/g for doping Co and 244.6 F/g for doping Fe. The thin films retained about 84% of the initial capacity even after 500 cycles of charge-discharge test. Doping Co and Fe decreases diffusion and charge transfer resistance of the films. The electric double layer capacitance and capacitor response frequency are increased after doping.
[Sufficiency with water-soluble vitamins and state of bone in pregnant women].
Vrzhesinskaya, O A; Pereverzeva, O G; Gmoshinskaya, M V; Kodentsova, V M; Safronova, A I; Korosteleva, M M; Aleshina, I V; Fandeeva, T A
2015-01-01
Vitamin status and bone strength have been estimated in 91 pregnant women (29.3 ± 4.6 years old) from Moscow by non-invasive methods. Sufficiency with vitamins C, B2, B6 has been evaluated by morning urinary excretion of ascorbic acid, riboflavin and 4-piridoxic acid determined by visual titration and fluorimetric methods. The rate of bone resorption has been measured by the ratio of urinary calcium and creatinine, determined by complexometric titration and spectrophotometrically. The study of the bone strength has been conducted using an ultrasonic densitometer (the speed of the ultrasonic waves along the cortical layer). The lack of vitamin C was found in 20.4% .of the women surveyed, vitamin B2--in 27.4%. Vitamin B6 deficiency was detected most frequently (90%). Excretion of vitamins B2 and B6 in women in the third trimester of pregnancy was lower as compared with the women in the first and second trimester. In 53.3% of the women surveyed an increase in urinary excretion of calcium per creatinine has been observed. Excretion of group B vitamins (especially vitamin B6, 1.75 fold, p < 0.05) in women taking vitamin supplements was higher compared to non-taking vitamins that indicates the better sufficiency of the organism with these vitamins. Among women who took vitamin complexes, inadequate supply with water-soluble vitamins C, B2 and B6 was detected less frequently (the difference was significant for vitamin B2) than among women who did not intake vitamin complexes (in 11.9, 27.7 and 42.4% vs 16.1, 54.8 and 48.8 %). The rate of bone resorption (Ca/creatinine) in women taking vitamins was smaller (0.19 ± 0.09 vs 0.24 ± 0.14, p > 0.05). Ca/creatinine ratio was within normal range in 40% of women who intake vitamins, while in women not taking vitamins--only in 22.2%; this value exceeded the upper limit of norm in the rest. The strength of bone was broken in women in the second and third trimester of pregnancy, having worse supply of vitamins. The percentage of agreement of the results of osteopenia diagnosis assessment (ultrasound densitometry and urinary Ca/creatinine) was 42.2%. Thus, the conclusion has been confirmed that the evaluation of the status of bone is possible only basing on the results of determination of several parameters.
Kararia, Vandana; Jain, Pradeep; Chaudhary, Seema; Kararia, Nitin
2015-01-01
The biocompatibility of orthodontic dental alloys has been investigated over the past 20 years, but the results have been inconclusive. The study compares standard 3 M Unitek nickel-titanium (NiTi) and stainless steel archwires with locally available JJ orthodontics wires. Scanning electron microscope (SEM) study of surface changes and complexometric titration to study compositional change was performed. Ten archwires each of group 1-3 M 0.016" NiTi, group 2-JJ 0.016" NiTi, group 3-3 M 0.019" *0.025" SS and group 4-JJ SS contributed a 10 mm piece of wire for analysis prior to insertion in the patient and 6 weeks post insertion. SEM images were recorded at ×2000, ×4000 and ×6000 magnification. The same samples were subjected to complexiometric titration using ethylenediaminetetraacetic acid to gauge the actual change in the composition. The SEM images of all the archwires showed marked changes with deep scratches and grooves and dark pitting corrosion areas post intraoral use. 3M wires showed an uniform criss-cross pattern in as received wires indicating a coating which was absent after intraoral use. There was a significant release of Nickel and Chromium from both group 3 and 4. Group 2 wires released ions significantly more than group 1 (P = 0.0). Extensive and stringent trials are required before certifying any product to be used in Orthodontics.
Kararia, Vandana; Jain, Pradeep; Chaudhary, Seema; Kararia, Nitin
2015-01-01
Introduction: The biocompatibility of orthodontic dental alloys has been investigated over the past 20 years, but the results have been inconclusive. The study compares standard 3 M Unitek nickel-titanium (NiTi) and stainless steel archwires with locally available JJ orthodontics wires. Scanning electron microscope (SEM) study of surface changes and complexometric titration to study compositional change was performed. Materials and Methods: Ten archwires each of group 1–3 M 0.016” NiTi, group 2-JJ 0.016” NiTi, group 3–3 M 0.019” *0.025” SS and group 4-JJ SS contributed a 10 mm piece of wire for analysis prior to insertion in the patient and 6 weeks post insertion. SEM images were recorded at ×2000, ×4000 and ×6000 magnification. The same samples were subjected to complexiometric titration using ethylenediaminetetraacetic acid to gauge the actual change in the composition. Observations and Results: The SEM images of all the archwires showed marked changes with deep scratches and grooves and dark pitting corrosion areas post intraoral use. 3M wires showed an uniform criss-cross pattern in as received wires indicating a coating which was absent after intraoral use. There was a significant release of Nickel and Chromium from both group 3 and 4. Group 2 wires released ions significantly more than group 1 (P = 0.0). Conclusion: Extensive and stringent trials are required before certifying any product to be used in Orthodontics. PMID:25684911
Abdesselem, Mouna; Schoeffel, Markus; Maurin, Isabelle; Ramodiharilafy, Rivo; Autret, Gwennhael; Clément, Olivier; Tharaux, Pierre-Louis; Boilot, Jean-Pierre; Gacoin, Thierry; Bouzigues, Cedric; Alexandrou, Antigoni
2014-11-25
Collecting information on multiple pathophysiological parameters is essential for understanding complex pathologies, especially given the large interindividual variability. We report here multifunctional nanoparticles which are luminescent probes, oxidant sensors, and contrast agents in magnetic resonance imaging (MRI). Eu(3+) ions in an yttrium vanadate matrix have been demonstrated to emit strong, nonblinking, and stable luminescence. Time- and space-resolved optical oxidant detection is feasible after reversible photoreduction of Eu(3+) to Eu(2+) and reoxidation by oxidants, such as H2O2, leading to a modulation of the luminescence emission. The incorporation of paramagnetic Gd(3+) confers in addition proton relaxation enhancing properties to the system. We synthesized and characterized nanoparticles of either 5 or 30 nm diameter with compositions of GdVO4 and Gd0.6Eu0.4VO4. These particles retain the luminescence and oxidant detection properties of YVO4:Eu. Moreover, the proton relaxivity of GdVO4 and Gd0.6Eu0.4VO4 nanoparticles of 5 nm diameter is higher than that of the commercial Gd(3+) chelate compound Dotarem at 20 MHz. Nuclear magnetic resonance dispersion spectroscopy showed a relaxivity increase above 10 MHz. Complexometric titration indicated that rare-earth leaching is negligible. The 5 nm nanoparticles injected in mice were observed with MRI to concentrate in the liver and the bladder after 30 min. Thus, these multifunctional rare-earth vanadate nanoparticles pave the way for simultaneous optical and magnetic resonance detection, in particular, for in vivo localization evolution and reactive oxygen species detection in a broad range of physiological and pathophysiological conditions.
Evidence of Multi-Component Ion Exchange in Dolomite Formation during Low Salinity Waterflooding
NASA Astrophysics Data System (ADS)
Srisuriyachai, Falan; Meekangwal, Suthida
2017-12-01
Low salinity waterflooding is a technique performed in many oil reservoirs around the globe. The technique is simply implemented by injecting water with very low ionic activity compared to formation water into an injection well. The injected water will increase reservoir pressure that is compulsory to drive oil moving toward production well. More than just maintaining reservoir pressure as obtained from conventional waterflooding, low salinity water creates shifting of surface condition, resulting in additional amount of liberated oil. Nevertheless, exact oil recovery mechanisms are still discussed. Among these proposed mechanisms, Multi-component Ion Exchange (MIE) together with wettability alteration is believed to be a major mechanism leading to higher oil recovery compared to conventional waterflooding. In this study, detection of calcium and magnesium ions which are Potential Determining Ions (PDI) for carbonate reservoirs are detected during the coreflood experiment. Dolomite rock sample is used to represent carbonate formation and detection of previously mentioned ions is performed by complexometric titration of the effluents. From the study, it is observed that during conventional waterflooding and low salinity waterflooding at low temperature of 30 degrees Celsius, calcium and magnesium ions in the produced water is increased compared to the amount of these ions in the injected water. This incremental of ions can be explained by the dissolution of calcium and magnesium from dolomite which is chemically composed of calcium magnesium carbonate. At this temperature, the portion of calcium ion is always less than magnesium ion even though the amount of calcium ion is higher than magnesium ion in injected water. However, at higher temperatures which are 50 and 70 degrees Celsius, ratio of calcium and magnesium ions in injected and produced water is reversed. Disappearance of magnesium ion in the effluent is more obvious especially at 70 degrees Celsius and by low salinity waterflooding. This can be explained that at lower temperature, calcium ion disappears to form of calcium carboxylate complex with oil and at higher temperature, magnesium ion disappears as magnesium can start to form magnesium carboxylate complex with oil and hence, the amount of both calcium and magnesium ions is decreased compared to lower temperature. In dolomite reservoir, since both calcium ions and magnesium ions are provided from dissolution mechanism, the benefit from multi-component ion exchange will occur at high temperature as both calcium and magnesium ions will be consumed for oil recovery mechanism.
van den Bogert, Cornelis A.; van Soest-Poortvliet, Mirjam C.; Fazeli Farsani, Soulmaz; Otten, René H. J.; ter Riet, Gerben; Bouter, Lex M.
2018-01-01
Background Selective reporting is wasteful, leads to bias in the published record and harms the credibility of science. Studies on potential determinants of selective reporting currently lack a shared taxonomy and a causal framework. Objective To develop a taxonomy of determinants of selective reporting in science. Design Inductive qualitative content analysis of a random selection of the pertinent literature including empirical research and theoretical reflections. Methods Using search terms for bias and selection combined with terms for reporting and publication, we systematically searched the PubMed, Embase, PsycINFO and Web of Science databases up to January 8, 2015. Of the 918 articles identified, we screened a 25 percent random selection. From eligible articles, we extracted phrases that mentioned putative or possible determinants of selective reporting, which we used to create meaningful categories. We stopped when no new categories emerged in the most recently analyzed articles (saturation). Results Saturation was reached after analyzing 64 articles. We identified 497 putative determinants, of which 145 (29%) were supported by empirical findings. The determinants represented 12 categories (leaving 3% unspecified): focus on preferred findings (36%), poor or overly flexible research design (22%), high-risk area and its development (8%), dependence upon sponsors (8%), prejudice (7%), lack of resources including time (3%), doubts about reporting being worth the effort (3%), limitations in reporting and editorial practices (3%), academic publication system hurdles (3%), unfavorable geographical and regulatory environment (2%), relationship and collaboration issues (2%), and potential harm (0.4%). Conclusions We designed a taxonomy of putative determinants of selective reporting consisting of 12 categories. The taxonomy may help develop theory about causes of selection bias and guide policies to prevent selective reporting. PMID:29401492
Selective catalyst reduction light-off strategy
Gonze, Eugene V [Pinckney, MI
2011-10-18
An emissions control system includes a temperature determination module and an emissions control module. The temperature determination module determines a first temperature of a heater element of a diesel particulate filter (DPF) assembly in an exhaust system and determines a second temperature of a catalyst of the DPF assembly. The emissions control module selectively activates the heater element, selectively initiates a predefined combustion process in an engine based upon the first temperature, and selectively starts a reductant injection process based upon the second temperature.
Determiner Selection in Romance Languages: Evidence from French
ERIC Educational Resources Information Center
Foucart, Alice; Branigan, Holly P.; Bard, Ellen G.
2010-01-01
Determiner selection requires the retrieval of the noun's syntactic features (e.g., gender) and sometimes of its phonological features. Miozzo and Caramazza (1999) argued that the selection of determiners in Germanic languages is more straightforward than in Romance languages because it is not dependent on the phonological properties of the…
Code of Federal Regulations, 2010 CFR
2010-07-01
... certification; test fleet selections; determinations of parameters subject to adjustment for certification and..., and for 1985 and Later Model Year New Gasoline Fueled, Natural Gas-Fueled, Liquefied Petroleum Gas...; test fleet selections; determinations of parameters subject to adjustment for certification and...
Code of Federal Regulations, 2011 CFR
2011-07-01
... certification; test fleet selections; determinations of parameters subject to adjustment for certification and..., and for 1985 and Later Model Year New Gasoline Fueled, Natural Gas-Fueled, Liquefied Petroleum Gas...; test fleet selections; determinations of parameters subject to adjustment for certification and...
Darlington, P J
1972-02-01
Mathematical biologists have failed to produce a satisfactory general model for evolution of altruism, i.e., of behaviors by which "altruists" benefit other individuals but not themselves; kin selection does not seem to be a sufficient explanation of nonreciprocal altruism. Nonmathematical (but mathematically acceptable) models are now proposed for evolution of negative altruism in dual-determinant and of positive altruism in tri-determinant systems. Peck orders, territorial systems, and an ant society are analyzed as examples. In all models, evolution is primarily by individual selection, probably supplemented by group selection. Group selection is differential extinction of populations. It can act only on populations preformed by selection at the individual level, but can either cancel individual selective trends (effecting evolutionary homeostasis) or supplement them; its supplementary effect is probably increasingly important in the evolution of increasingly organized populations.
A Note on the Determination of "Acceptable" Performance in Thorndike's Standard of Fair Selection.
ERIC Educational Resources Information Center
Brown, Charles
1980-01-01
The determination of acceptable performance in Thorndike's constant ratio standard of fair selection is considered. It is shown that suitable choice of acceptable performance can make any minority-majority selection disparity consistent with Thorndike's standard. A rule for determining acceptable performance which avoids the Petersen-Novick…
Crutzen, Rik; Peters, Gjalt-Jorn Ygram; Noijen, Judith
2017-01-01
When developing an intervention aimed at behavior change, one of the crucial steps in the development process is to select the most relevant social-cognitive determinants. These determinants can be seen as the buttons one needs to push to establish behavior change. Insight into these determinants is needed to select behavior change methods (i.e., general behavior change techniques that are applied in an intervention) in the development process. Therefore, a study on determinants is often conducted as formative research in the intervention development process. Ideally, all relevant determinants identified in such a study are addressed by an intervention. However, when developing a behavior change intervention, there are limits in terms of, for example, resources available for intervention development and the amount of content that participants of an intervention can be exposed to. Hence, it is important to select those determinants that are most relevant to the target behavior as these determinants should be addressed in an intervention. The aim of the current paper is to introduce a novel approach to select the most relevant social-cognitive determinants and use them in intervention development. This approach is based on visualization of confidence intervals for the means and correlation coefficients for all determinants simultaneously. This visualization facilitates comparison, which is necessary when making selections. By means of a case study on the determinants of using a high dose of 3,4-methylenedioxymethamphetamine (commonly known as ecstasy), we illustrate this approach. We provide a freely available tool to facilitate the analyses needed in this approach.
Method of Controlling Steering of a Ground Vehicle
NASA Technical Reports Server (NTRS)
Guo, Raymond (Inventor); Atluri, Venkata Prasad (Inventor); Bluethmann, William J. (Inventor); Lee, Chunhao J. (Inventor); Vitale, Robert L. (Inventor); Dawson, Andrew D. (Inventor)
2016-01-01
A method of controlling steering of a vehicle through setting wheel angles of a plurality of modular electronic corner assemblies (eModules) is provided. The method includes receiving a driving mode selected from a mode selection menu. A position of a steering input device is determined in a master controller. A velocity of the vehicle is determined, in the master controller, when the determined position of the steering input device is near center. A drive mode request corresponding to the selected driving mode to the plurality of steering controllers is transmitted to the master controller. A required steering angle of each of the plurality of eModules is determined, in the master controller, as a function of the determined position of the steering input device, the determined velocity of the vehicle, and the selected first driving mode. The eModules are set to the respective determined steering angles.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Clay, Raymond C.; Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore, California 94550; Morales, Miguel A., E-mail: moralessilva2@llnl.gov
2015-06-21
Multideterminant wavefunctions, while having a long history in quantum chemistry, are increasingly being used in highly accurate quantum Monte Carlo calculations. Since the accuracy of QMC is ultimately limited by the quality of the trial wavefunction, multi-Slater determinants wavefunctions offer an attractive alternative to Slater-Jastrow and more sophisticated wavefunction ansatz for several reasons. They can be efficiently calculated, straightforwardly optimized, and systematically improved by increasing the number of included determinants. In spite of their potential, however, the convergence properties of multi-Slater determinant wavefunctions with respect to orbital set choice and excited determinant selection are poorly understood, which hinders the applicationmore » of these wavefunctions to large systems and solids. In this paper, by performing QMC calculations on the equilibrium and stretched carbon dimer, we find that convergence of the recovered correlation energy with respect to number of determinants can depend quite strongly on basis set and determinant selection methods, especially where there is strong correlation. We demonstrate that properly chosen orbital sets and determinant selection techniques from quantum chemistry methods can dramatically reduce the required number of determinants (and thus the computational cost) to reach a given accuracy, which we argue shows clear need for an automatic QMC-only method for selecting determinants and generating optimal orbital sets.« less
Selection Gradients, the Opportunity for Selection, and the Coefficient of Determination
Moorad, Jacob A.; Wade, Michael J.
2013-01-01
We derive the relationship between R2 (the coefficient of determination), selection gradients, and the opportunity for selection for univariate and multivariate cases. Our main result is to show that the portion of the opportunity for selection that is caused by variation for any trait is equal to the product of its selection gradient and its selection differential. This relationship is a corollary of the first and second fundamental theorems of natural selection, and it permits one to investigate the portions of the total opportunity for selection that are involved in directional selection, stabilizing (and diversifying) selection, and correlational selection, which is important to morphological integration. It also allows one to determine the fraction of fitness variation not explained by variation in measured phenotypes and therefore attributable to random (or, at least, unknown) influences. We apply our methods to a human data set to show how sex-specific mating success as a component of fitness variance can be decoupled from that owing to prereproductive mortality. By quantifying linear sources of sexual selection and quadratic sources of sexual selection, we illustrate that the former is stronger in males, while the latter is stronger in females. PMID:23448880
Selection gradients, the opportunity for selection, and the coefficient of determination.
Moorad, Jacob A; Wade, Michael J
2013-03-01
Abstract We derive the relationship between R(2) (the coefficient of determination), selection gradients, and the opportunity for selection for univariate and multivariate cases. Our main result is to show that the portion of the opportunity for selection that is caused by variation for any trait is equal to the product of its selection gradient and its selection differential. This relationship is a corollary of the first and second fundamental theorems of natural selection, and it permits one to investigate the portions of the total opportunity for selection that are involved in directional selection, stabilizing (and diversifying) selection, and correlational selection, which is important to morphological integration. It also allows one to determine the fraction of fitness variation not explained by variation in measured phenotypes and therefore attributable to random (or, at least, unknown) influences. We apply our methods to a human data set to show how sex-specific mating success as a component of fitness variance can be decoupled from that owing to prereproductive mortality. By quantifying linear sources of sexual selection and quadratic sources of sexual selection, we illustrate that the former is stronger in males, while the latter is stronger in females.
John W. Edwards; Susan C. Loeb; David C. Guynn
1994-01-01
Multiple regression and use-availability analyses are two methods for examining habitat selection. Use-availability analysis is commonly used to evaluate macrohabitat selection whereas multiple regression analysis can be used to determine microhabitat selection. We compared these techniques using behavioral observations (n = 5534) and telemetry locations (n = 2089) of...
ERIC Educational Resources Information Center
Spalek, Katharina; Bock, Kathryn; Schriefers, Herbert
2010-01-01
The form of a determiner is dependent on different contextual factors: in some languages grammatical number and grammatical gender determine the choice of a determiner variant. In other languages, the phonological onset of the element immediately following the determiner affects selection, too. Previous work has shown that the activation of…
Selection of Wavelengths for Optimum Precision in Simultaneous Spectrophotometric Determinations.
ERIC Educational Resources Information Center
DiTusa, Michael R.; Schilt, Alfred A.
1985-01-01
Although many textbooks include a description of simultaneous determinations employing absorption spectrophotometry and treat the mathematics necessary for analytical quantitations, treatment of analytical wavelength selection has been mostly qualitative. Therefore, a general method for selecting wavelengths for optimum precision in simultaneous…
Generating a Simulated Fluid Flow over a Surface Using Anisotropic Diffusion
NASA Technical Reports Server (NTRS)
Rodriguez, David L. (Inventor); Sturdza, Peter (Inventor)
2016-01-01
A fluid-flow simulation over a computer-generated surface is generated using a diffusion technique. The surface is comprised of a surface mesh of polygons. A boundary-layer fluid property is obtained for a subset of the polygons of the surface mesh. A gradient vector is determined for a selected polygon, the selected polygon belonging to the surface mesh but not one of the subset of polygons. A maximum and minimum diffusion rate is determined along directions determined using the gradient vector corresponding to the selected polygon. A diffusion-path vector is defined between a point in the selected polygon and a neighboring point in a neighboring polygon. An updated fluid property is determined for the selected polygon using a variable diffusion rate, the variable diffusion rate based on the minimum diffusion rate, maximum diffusion rate, and the gradient vector.
Bijma, Piter
2011-01-01
Genetic selection is a major force shaping life on earth. In classical genetic theory, response to selection is the product of the strength of selection and the additive genetic variance in a trait. The additive genetic variance reflects a population’s intrinsic potential to respond to selection. The ordinary additive genetic variance, however, ignores the social organization of life. With social interactions among individuals, individual trait values may depend on genes in others, a phenomenon known as indirect genetic effects. Models accounting for indirect genetic effects, however, lack a general definition of heritable variation. Here I propose a general definition of the heritable variation that determines the potential of a population to respond to selection. This generalizes the concept of heritable variance to any inheritance model and level of organization. The result shows that heritable variance determining potential response to selection is the variance among individuals in the heritable quantity that determines the population mean trait value, rather than the usual additive genetic component of phenotypic variance. It follows, therefore, that heritable variance may exceed phenotypic variance among individuals, which is impossible in classical theory. This work also provides a measure of the utilization of heritable variation for response to selection and integrates two well-known models of maternal genetic effects. The result shows that relatedness between the focal individual and the individuals affecting its fitness is a key determinant of the utilization of heritable variance for response to selection. PMID:21926298
Bijma, Piter
2011-12-01
Genetic selection is a major force shaping life on earth. In classical genetic theory, response to selection is the product of the strength of selection and the additive genetic variance in a trait. The additive genetic variance reflects a population's intrinsic potential to respond to selection. The ordinary additive genetic variance, however, ignores the social organization of life. With social interactions among individuals, individual trait values may depend on genes in others, a phenomenon known as indirect genetic effects. Models accounting for indirect genetic effects, however, lack a general definition of heritable variation. Here I propose a general definition of the heritable variation that determines the potential of a population to respond to selection. This generalizes the concept of heritable variance to any inheritance model and level of organization. The result shows that heritable variance determining potential response to selection is the variance among individuals in the heritable quantity that determines the population mean trait value, rather than the usual additive genetic component of phenotypic variance. It follows, therefore, that heritable variance may exceed phenotypic variance among individuals, which is impossible in classical theory. This work also provides a measure of the utilization of heritable variation for response to selection and integrates two well-known models of maternal genetic effects. The result shows that relatedness between the focal individual and the individuals affecting its fitness is a key determinant of the utilization of heritable variance for response to selection.
Systematic wavelength selection for improved multivariate spectral analysis
Thomas, Edward V.; Robinson, Mark R.; Haaland, David M.
1995-01-01
Methods and apparatus for determining in a biological material one or more unknown values of at least one known characteristic (e.g. the concentration of an analyte such as glucose in blood or the concentration of one or more blood gas parameters) with a model based on a set of samples with known values of the known characteristics and a multivariate algorithm using several wavelength subsets. The method includes selecting multiple wavelength subsets, from the electromagnetic spectral region appropriate for determining the known characteristic, for use by an algorithm wherein the selection of wavelength subsets improves the model's fitness of the determination for the unknown values of the known characteristic. The selection process utilizes multivariate search methods that select both predictive and synergistic wavelengths within the range of wavelengths utilized. The fitness of the wavelength subsets is determined by the fitness function F=.function.(cost, performance). The method includes the steps of: (1) using one or more applications of a genetic algorithm to produce one or more count spectra, with multiple count spectra then combined to produce a combined count spectrum; (2) smoothing the count spectrum; (3) selecting a threshold count from a count spectrum to select these wavelength subsets which optimize the fitness function; and (4) eliminating a portion of the selected wavelength subsets. The determination of the unknown values can be made: (1) noninvasively and in vivo; (2) invasively and in vivo; or (3) in vitro.
Selection of forages by timor deer (cervus timorensis blainville) in menjangan island, bali
NASA Astrophysics Data System (ADS)
Ketut Ginantra, I.; Bagus Made Suaskara, Ida; Ketut Muksin, I.
2018-03-01
This study was conducted to determine the selection of forages plants by Timor deer (Cervus timorensis) on Menjangan Island and its relation to the availability, chemical and physical properties of feed plants. The study was conducted in July-September 2016 in savanna and monsoon forest habitats. The availability of habitat feed plants in the habitat was determined by the quadrat method, and the species of plant eaten by Timor deer was determined through the microhistological analysis of the fecal sample. The food selection index is determine by the Ivlev index. Energy contents of forages plants by bomb calorimeter apparatus, crude protein analyzed by Semi-Micro Kjeldahl technique, NDF, ADF and lignin levels refer to the method of Goering and Van Soest. Mineral content of calcium (Ca) and phosphorus (P) by using atomic absorption spectrophotometer. Determination of tannin content with Folin Denish reaction. Physical properties determine are water regain capacity and water solubility. The relationship between availability with the utilization of plants by Timor deer was analyzed with the similarity index. Multiple regression statistic to test the relationship between index selection with nutritional value factor and physical characteristic of plant species. The result showed that Timor deer selected 32 plants species of graminoids, forbs and woody plants. Feeding selection of Timor deer is strongly influenced by the availability of forage plants in habitat. The feeding selection was significantly influenced by three predictor variables i.e. positive nutritional value is crude protein and negative nutritional value were lignin and tannins. Selection of forage plant Timor deer is positively correlated with the physical properties of feed plants.
Zhan, Xue-yan; Zhao, Na; Lin, Zhao-zhou; Wu, Zhi-sheng; Yuan, Rui-juan; Qiao, Yan-jiang
2014-12-01
The appropriate algorithm for calibration set selection was one of the key technologies for a good NIR quantitative model. There are different algorithms for calibration set selection, such as Random Sampling (RS) algorithm, Conventional Selection (CS) algorithm, Kennard-Stone(KS) algorithm and Sample set Portioning based on joint x-y distance (SPXY) algorithm, et al. However, there lack systematic comparisons between two algorithms of the above algorithms. The NIR quantitative models to determine the asiaticoside content in Centella total glucosides were established in the present paper, of which 7 indexes were classified and selected, and the effects of CS algorithm, KS algorithm and SPXY algorithm for calibration set selection on the accuracy and robustness of NIR quantitative models were investigated. The accuracy indexes of NIR quantitative models with calibration set selected by SPXY algorithm were significantly different from that with calibration set selected by CS algorithm or KS algorithm, while the robustness indexes, such as RMSECV and |RMSEP-RMSEC|, were not significantly different. Therefore, SPXY algorithm for calibration set selection could improve the predicative accuracy of NIR quantitative models to determine asiaticoside content in Centella total glucosides, and have no significant effect on the robustness of the models, which provides a reference to determine the appropriate algorithm for calibration set selection when NIR quantitative models are established for the solid system of traditional Chinese medcine.
Method and apparatus for monitoring a hydrocarbon-selective catalytic reduction device
Schmieg, Steven J; Viola, Michael B; Cheng, Shi-Wai S; Mulawa, Patricia A; Hilden, David L; Sloane, Thompson M; Lee, Jong H
2014-05-06
A method for monitoring a hydrocarbon-selective catalytic reactor device of an exhaust aftertreatment system of an internal combustion engine operating lean of stoichiometry includes injecting a reductant into an exhaust gas feedstream upstream of the hydrocarbon-selective catalytic reactor device at a predetermined mass flowrate of the reductant, and determining a space velocity associated with a predetermined forward portion of the hydrocarbon-selective catalytic reactor device. When the space velocity exceeds a predetermined threshold space velocity, a temperature differential across the predetermined forward portion of the hydrocarbon-selective catalytic reactor device is determined, and a threshold temperature as a function of the space velocity and the mass flowrate of the reductant is determined. If the temperature differential across the predetermined forward portion of the hydrocarbon-selective catalytic reactor device is below the threshold temperature, operation of the engine is controlled to regenerate the hydrocarbon-selective catalytic reactor device.
76 FR 27374 - Determination To Transfer Title of Selected Aircraft to the Government of Mexico
Federal Register 2010, 2011, 2012, 2013, 2014
2011-05-11
... DEPARTMENT OF STATE [Public Notice: 7453] Determination To Transfer Title of Selected Aircraft to... determine that section 484(a)(1) of the Act (Which requires that the United States retain title to aircraft... interest to transfer title. This Determination, supported by the Memorandum of Justification, Section 484...
Generating a Simulated Fluid Flow Over an Aircraft Surface Using Anisotropic Diffusion
NASA Technical Reports Server (NTRS)
Rodriguez, David L. (Inventor); Sturdza, Peter (Inventor)
2013-01-01
A fluid-flow simulation over a computer-generated aircraft surface is generated using a diffusion technique. The surface is comprised of a surface mesh of polygons. A boundary-layer fluid property is obtained for a subset of the polygons of the surface mesh. A pressure-gradient vector is determined for a selected polygon, the selected polygon belonging to the surface mesh but not one of the subset of polygons. A maximum and minimum diffusion rate is determined along directions determined using a pressure gradient vector corresponding to the selected polygon. A diffusion-path vector is defined between a point in the selected polygon and a neighboring point in a neighboring polygon. An updated fluid property is determined for the selected polygon using a variable diffusion rate, the variable diffusion rate based on the minimum diffusion rate, maximum diffusion rate, and angular difference between the diffusion-path vector and the pressure-gradient vector.
Mitchell, Timothy S; Maciel, Jessica A; Janzen, Fredric J
2013-12-07
Evolutionary theory predicts that dioecious species should produce a balanced primary sex ratio maintained by frequency-dependent selection. Organisms with environmental sex determination, however, are vulnerable to maladaptive sex ratios, because environmental conditions vary spatio-temporally. For reptiles with temperature-dependent sex determination, nest-site choice is a behavioural maternal effect that could respond to sex-ratio selection, as mothers could adjust offspring sex ratios by choosing nest sites that will have particular thermal properties. This theoretical prediction has generated decades of empirical research, yet convincing evidence that sex-ratio selection is influencing nesting behaviours remains absent. Here, we provide the first experimental evidence from nature that sex-ratio selection, rather than only viability selection, is probably an important component of nest-site choice in a reptile with temperature-dependent sex determination. We compare painted turtle (Chrysemys picta) neonates from maternally selected nest sites with those from randomly selected nest sites, observing no substantive difference in hatching success or survival, but finding a profound difference in offspring sex ratio in the direction expected based on historical records. Additionally, we leverage long-term data to reconstruct our sex ratio results had the experiment been repeated in multiple years. As predicted by theory, our results suggest that sex-ratio selection has shaped nesting behaviour in ways likely to enhance maternal fitness.
Mitchell, Timothy S.; Maciel, Jessica A.; Janzen, Fredric J.
2013-01-01
Evolutionary theory predicts that dioecious species should produce a balanced primary sex ratio maintained by frequency-dependent selection. Organisms with environmental sex determination, however, are vulnerable to maladaptive sex ratios, because environmental conditions vary spatio-temporally. For reptiles with temperature-dependent sex determination, nest-site choice is a behavioural maternal effect that could respond to sex-ratio selection, as mothers could adjust offspring sex ratios by choosing nest sites that will have particular thermal properties. This theoretical prediction has generated decades of empirical research, yet convincing evidence that sex-ratio selection is influencing nesting behaviours remains absent. Here, we provide the first experimental evidence from nature that sex-ratio selection, rather than only viability selection, is probably an important component of nest-site choice in a reptile with temperature-dependent sex determination. We compare painted turtle (Chrysemys picta) neonates from maternally selected nest sites with those from randomly selected nest sites, observing no substantive difference in hatching success or survival, but finding a profound difference in offspring sex ratio in the direction expected based on historical records. Additionally, we leverage long-term data to reconstruct our sex ratio results had the experiment been repeated in multiple years. As predicted by theory, our results suggest that sex-ratio selection has shaped nesting behaviour in ways likely to enhance maternal fitness. PMID:24266033
Sex selection and restricting abortion and sex determination.
Zilberberg, Julie
2007-11-01
Sex selection in India and China is fostered by a limiting social structure that disallows women from performing the roles that men perform, and relegates women to a lower status level. Individual parents and individual families benefit concretely from having a son born into the family, while society, and girls and women as a group, are harmed by the widespread practice of sex selection. Sex selection reinforces oppression of women and girls. Sex selection is best addressed by ameliorating the situations of women and girls, increasing their autonomy, and elevating their status in society. One might argue that restricting or prohibiting abortion, prohibiting sex selection, and prohibiting sex determination would eliminate sex selective abortion. But this decreases women's autonomy rather than increases it. Such practices will turn underground. Sex selective infanticide, and slower death by long term neglect, could increase. If abortion is restricted, the burden is placed on women seeking abortions to show that they have a legally acceptable or legitimate reason for a desired abortion, and this seriously limits women's autonomy. Instead of restricting abortion, banning sex selection, and sex determination, it is better to address the practice of sex selection by elevating the status of women and empowering women so that giving birth to a girl is a real and positive option, instead of a detriment to the parents and family as it is currently. But, if a ban on sex selective abortion or a ban on sex determination is indeed instituted, then wider social change promoting women's status in society should be instituted simultaneously.
DOE Office of Scientific and Technical Information (OSTI.GOV)
None
A system according to the principles of the present disclosure includes an air/fuel ratio determination module and an emission level determination module. The air/fuel ratio determination module determines an air/fuel ratio based on input from an air/fuel ratio sensor positioned downstream from a three-way catalyst that is positioned upstream from a selective catalytic reduction (SCR) catalyst. The emission level determination module selects one of a predetermined value and an input based on the air/fuel ratio. The input is received from a nitrogen oxide sensor positioned downstream from the three-way catalyst. The emission level determination module determines an ammonia level basedmore » on the one of the predetermined value and the input received from the nitrogen oxide sensor.« less
Grammatical and Nongrammatical Contributions to Closed-Class Word Selection
ERIC Educational Resources Information Center
Alario, F.-Xavier; Ayora, Pauline; Costa, Albert; Melinger, Alissa
2008-01-01
Closed-class word selection was investigated by focusing on determiner production. Native speakers from three different languages named pictures of objects using determiner plus noun phrases (e.g., in French "la table" (the [subscript feminine] table), while ignoring distractor determiners printed on the pictures (e.g., "le"…
Kotter, Dale K [Shelley, ID; Rohrbaugh, David T [Idaho Falls, ID
2010-09-07
A frequency selective surface (FSS) and associated methods for modeling, analyzing and designing the FSS are disclosed. The FSS includes a pattern of conductive material formed on a substrate to form an array of resonance elements. At least one aspect of the frequency selective surface is determined by defining a frequency range including multiple frequency values, determining a frequency dependent permittivity across the frequency range for the substrate, determining a frequency dependent conductivity across the frequency range for the conductive material, and analyzing the frequency selective surface using a method of moments analysis at each of the multiple frequency values for an incident electromagnetic energy impinging on the frequency selective surface. The frequency dependent permittivity and the frequency dependent conductivity are included in the method of moments analysis.
ERIC Educational Resources Information Center
Diamandis, E. P.; And Others
1983-01-01
The kinetic of the Jaffe reaction with picrate ion selective electrode (ISE) and a kinetic method for determining creatinine in urine is presented. The experiment could be used to familarize students with the application of ISE in kinetic studies and chemical analysis. (Author/JN)
Federal Register 2010, 2011, 2012, 2013, 2014
2012-05-29
... With Discretion to Determine Whether Parties to a FINRA Mediation May Select a Mediator Who Is Not on... Director'') with discretion to determine whether parties to a FINRA mediation may select a mediator who is... mediation to select a mediator either from a list of FINRA mediators supplied by the Mediation Director, or...
Signatures of selection among sex-determining alleles of the honey bee.
Hasselmann, Martin; Beye, Martin
2004-04-06
Patterns of DNA polymorphisms are a primary tool for dissecting signatures of selection; however, the underlying selective forces are poorly understood for most genes. A classical example of diversifying selection is the complementary sex-determining locus that is found in the very large insect order Hymenoptera (bees, wasps, ants, and sawflies). The gene responsible for sex determination, the complementary sex determiner (csd), has been most recently identified in the honey bee. Females are heterozygous at this locus. Males result when there is only one functional allele present, as a result of either homozygosity (fertilized eggs) or, more commonly, hemizygosity (unfertilized eggs). The homozygotes, diploid males, do not reproduce and have zero fitness, which implies positive selection in favor of rare alleles. Large differences in csd cDNA sequences within and between four populations were found that fall into two major groups, types I and II. Type I consists of several allelic lineages that were maintained over an extended period, an indication of balancing selection. Diversifying selection has operated on several confined parts of the protein, as shown by an excess of nonsynonymous differences. Elevated sequence differences indicate another selected part near a repeat region. These findings have general implications about the understanding of both the function of the multiallelic mechanism and the adaptive processes on the level of nucleotide sequences. Moreover, the first csd sequence data are a notable basis for the avoidance of diploid males in bee selection programs by allele-assisted breeding.
Patterns and Mechanisms of Evolutionary Transitions between Genetic Sex-Determining Systems
Sander van Doorn, G.
2014-01-01
The diversity and patchy phylogenetic distribution of genetic sex-determining mechanisms observed in some taxa is thought to have arisen by the addition, modification, or replacement of regulators at the upstream end of the sex-determining pathway. Here, I review the various evolutionary forces acting on upstream regulators of sexual development that can cause transitions between sex-determining systems. These include sex-ratio selection and pleiotropic benefits, as well as indirect selection mechanisms involving sex-linked sexually antagonistic loci or recessive deleterious mutations. Most of the current theory concentrates on the population–genetic aspects of sex-determination transitions, using models that do not reflect the developmental mechanisms involved in sex determination. However, the increasing availability of molecular data creates opportunities for the development of mechanistic models that can clarify how selection and developmental architecture interact to direct the evolution of sex-determination genes. PMID:24993578
NASA Astrophysics Data System (ADS)
Kwak, Kyuju; Kumar, S. Senthil; Lee, Dongil
2012-06-01
We report here the selective determination of dopamine (DA) using quantum-sized gold nanoparticles coated with charge selective ligands. Glutathione protected gold nanoparticles (GS-Au25) were synthesized and immobilized into a sol-gel matrix via thiol linkers. The GS-Au25 modified sol-gel electrode was found to show excellent electrocatalytic activity towards the oxidation of DA but no activity towards the oxidation of ascorbic acid. The role of electrostatic charge in the selective electrocatalytic activity of GS-Au25 was verified by voltammetry of redox markers carrying opposite charges. The pH dependent sensitivity for the determination of DA further confirmed the charge screening effect of GS-Au25. Mechanistic investigation revealed that the selectivity is attained by the selective formation of an electrostatic complex between the negatively charged GS-Au25 and DA cation. The GS-Au25 modified sol-gel electrode also showed excellent selectivity for DA in the presence of an interferent, ascorbic acid.We report here the selective determination of dopamine (DA) using quantum-sized gold nanoparticles coated with charge selective ligands. Glutathione protected gold nanoparticles (GS-Au25) were synthesized and immobilized into a sol-gel matrix via thiol linkers. The GS-Au25 modified sol-gel electrode was found to show excellent electrocatalytic activity towards the oxidation of DA but no activity towards the oxidation of ascorbic acid. The role of electrostatic charge in the selective electrocatalytic activity of GS-Au25 was verified by voltammetry of redox markers carrying opposite charges. The pH dependent sensitivity for the determination of DA further confirmed the charge screening effect of GS-Au25. Mechanistic investigation revealed that the selectivity is attained by the selective formation of an electrostatic complex between the negatively charged GS-Au25 and DA cation. The GS-Au25 modified sol-gel electrode also showed excellent selectivity for DA in the presence of an interferent, ascorbic acid. Electronic supplementary information (ESI) available: TEM image of GS-Au25, SWV of GS-Au25 in solution, effect of scan rate on the CV of GS-Au25ME, CVs of DA and AA at the bare GCE and CVs of GS-Au25ME at different pHs. See DOI: 10.1039/c2nr30481c
Ayala Quezada, Alejandro; Ohara, Keisuke; Ratanawimarnwong, Nuanlaor; Nacapricha, Duangjai; Murakami, Hiroya; Teshima, Norio; Sakai, Tadao
2015-11-01
An automated stopped-in-loop flow analysis (SILFA) system is proposed for the successive catalytic determination of vanadium and iron. The determination of vanadium was based on the p-anisidine oxidation by potassium bromate in the presence of Tiron as an activator to form a reddish dye, which has an absorption maximum at 510 nm. The selectivity of the vanadium determination was greatly improved by adding diphosphate as a masking agent of iron. For the iron determination, an iron-catalyzed oxidative reaction of p-anisidine by hydrogen peroxide with 1,10-phenanthroline as an activator to produce a reddish dye (510 nm) was employed. The SILFA system consisted of two peristaltic pumps, two six-port injection valves, a four-port selection valve, a heater device, a spectrophotometric detector and a data acquisition device. One six-port injection valve was used for the isolation of a mixed solution of standard/sample and reagent to promote each catalytic reaction, and another six-port injection valve was used for switching the reagent for vanadium or iron to achieve selective determination of each analyte. The above mentioned four-port selection valve was used to select standard solutions or sample. These three valves and the two peristaltic pumps were controlled by a built-in programmable logic controller in a touchscreen controller. The obtained results showed that the proposed SILFA monitoring system constituted an effective approach for the selective determination of vanadium and iron. The limits of detection, 0.052 and 0.55 µg L(-1), were obtained for vanadium and iron, respectively. The proposed system was successfully applied to drinking water samples without any preconcentration procedures. Copyright © 2015 Elsevier B.V. All rights reserved.
Cho, Soochin; Huang, Zachary Y; Green, Daniel R; Smith, Deborah R; Zhang, Jianzhi
2006-11-01
The mechanism of sex determination varies substantively among evolutionary lineages. One important mode of genetic sex determination is haplodiploidy, which is used by approximately 20% of all animal species, including >200,000 species of the entire insect order Hymenoptera. In the honey bee Apis mellifera, a hymenopteran model organism, females are heterozygous at the csd (complementary sex determination) locus, whereas males are hemizygous (from unfertilized eggs). Fertilized homozygotes develop into sterile males that are eaten before maturity. Because homozygotes have zero fitness and because common alleles are more likely than rare ones to form homozygotes, csd should be subject to strong overdominant selection and negative frequency-dependent selection. Under these selective forces, together known as balancing selection, csd is expected to exhibit a high degree of intraspecific polymorphism, with long-lived alleles that may be even older than the species. Here we sequence the csd genes as well as randomly selected neutral genomic regions from individuals of three closely related species, A. mellifera, Apis cerana, and Apis dorsata. The polymorphic level is approximately seven times higher in csd than in the neutral regions. Gene genealogies reveal trans-species polymorphisms at csd but not at any neutral regions. Consistent with the prediction of rare-allele advantage, nonsynonymous mutations are found to be positively selected in csd only in early stages after their appearances. Surprisingly, three different hypervariable repetitive regions in csd are present in the three species, suggesting variable mechanisms underlying allelic specificities. Our results provide a definitive demonstration of balancing selection acting at the honey bee csd gene, offer insights into the molecular determinants of csd allelic specificities, and help avoid homozygosity in bee breeding.
Doughten, M.W.; Gillison, J.R.
1990-01-01
Methods for the determination of 24 elements in whole coal and coal ash by inductively coupled argon plasma-atomic emission spectrometry, flame, graphite furnace, and cold vapor atomic absorption spectrometry, and by ion-selective electrode are described. Coal ashes were analyzed in triplicate to determine the precision of the methods. Results of the analyses of NBS Standard Reference Materials 1633, 1633a, 1632a, and 1635 are reported. Accuracy of the methods is determined by comparison of the analysis of standard reference materials to their certified values as well as other values in the literature.
Method to monitor HC-SCR catalyst NOx reduction performance for lean exhaust applications
Viola, Michael B [Macomb Township, MI; Schmieg, Steven J [Troy, MI; Sloane, Thompson M [Oxford, MI; Hilden, David L [Shelby Township, MI; Mulawa, Patricia A [Clinton Township, MI; Lee, Jong H [Rochester Hills, MI; Cheng, Shi-Wai S [Troy, MI
2012-05-29
A method for initiating a regeneration mode in selective catalytic reduction device utilizing hydrocarbons as a reductant includes monitoring a temperature within the aftertreatment system, monitoring a fuel dosing rate to the selective catalytic reduction device, monitoring an initial conversion efficiency, selecting a determined equation to estimate changes in a conversion efficiency of the selective catalytic reduction device based upon the monitored temperature and the monitored fuel dosing rate, estimating changes in the conversion efficiency based upon the determined equation and the initial conversion efficiency, and initiating a regeneration mode for the selective catalytic reduction device based upon the estimated changes in conversion efficiency.
Determining a Retention Model for the Selected Marine Corps Reserve
2016-03-01
RETENTION MODEL FOR THE SELECTED MARINE CORPS RESERVE by Andrew D. Dausman March 2016 Thesis Advisor: Marigee Bacolod Co-Advisor: Chad W...2016 3. REPORT TYPE AND DATES COVERED Master’s thesis 4. TITLE AND SUBTITLE DETERMINING A RETENTION MODEL FOR THE SELECTED MARINE CORPS RESERVE...Approved for public release; distribution is unlimited 12b. DISTRIBUTION CODE A 13. ABSTRACT (maximum 200 words) This thesis develops a retention
NASA Astrophysics Data System (ADS)
Tian, Han; Li, Ming; Wang, Yue; Sheng, Dinggao; Liu, Jun; Zhang, Linna
2017-11-01
Hemoglobin concentration is commonly used in clinical medicine to diagnose anemia, identify bleeding, and manage red blood cell transfusions. The golden standard method for determining hemoglobin concentration in blood requires reagent. Spectral methods were advantageous at fast and non-reagent measurement. However, model calibration with full spectrum is time-consuming. Moreover, it is necessary to use a few variables considering size and cost of instrumentation, especially for a portable biomedical instrument. This study presents different wavelength selection methods for optical wavelengths for total hemoglobin concentration determination in whole blood. The results showed that modelling using only two wavelengths combination (1143 nm, 1298 nm) can keep on the fine predictability with full spectrum. It appears that the proper selection of optical wavelengths can be more effective than using the whole spectra for determination hemoglobin in whole blood. We also discussed the influence of water absorptivity on the wavelength selection. This research provides valuable references for designing portable NIR instruments determining hemoglobin concentration, and may provide some experience for noninvasive hemoglobin measurement by NIR methods.
DETERMINATION OF HENRY'S LAW CONSTANTS OF SELECTED PRIORITY POLLUTANTS
The Henry's law constants (H) for 41 selected priority pollutants were determined to characterize these pollutants and provide information on their fate as they pass through wastewater treatment systems. All experimental values presented for H are averages of two or more replicat...
Darvasi, A.; Soller, M.
1994-01-01
Selective genotyping is a method to reduce costs in marker-quantitative trait locus (QTL) linkage determination by genotyping only those individuals with extreme, and hence most informative, quantitative trait values. The DNA pooling strategy (termed: ``selective DNA pooling'') takes this one step further by pooling DNA from the selected individuals at each of the two phenotypic extremes, and basing the test for linkage on marker allele frequencies as estimated from the pooled samples only. This can reduce genotyping costs of marker-QTL linkage determination by up to two orders of magnitude. Theoretical analysis of selective DNA pooling shows that for experiments involving backcross, F(2) and half-sib designs, the power of selective DNA pooling for detecting genes with large effect, can be the same as that obtained by individual selective genotyping. Power for detecting genes with small effect, however, was found to decrease strongly with increase in the technical error of estimating allele frequencies in the pooled samples. The effect of technical error, however, can be markedly reduced by replication of technical procedures. It is also shown that a proportion selected of 0.1 at each tail will be appropriate for a wide range of experimental conditions. PMID:7896115
Linking seasonal home range size with habitat selection and movement in a mountain ungulate.
Viana, Duarte S; Granados, José Enrique; Fandos, Paulino; Pérez, Jesús M; Cano-Manuel, Francisco Javier; Burón, Daniel; Fandos, Guillermo; Aguado, María Ángeles Párraga; Figuerola, Jordi; Soriguer, Ramón C
2018-01-01
Space use by animals is determined by the interplay between movement and the environment, and is thus mediated by habitat selection, biotic interactions and intrinsic factors of moving individuals. These processes ultimately determine home range size, but their relative contributions and dynamic nature remain less explored. We investigated the role of habitat selection, movement unrelated to habitat selection and intrinsic factors related to sex in driving space use and home range size in Iberian ibex, Capra pyrenaica . We used GPS collars to track ibex across the year in two different geographical areas of Sierra Nevada, Spain, and measured habitat variables related to forage and roost availability. By using integrated step selection analysis (iSSA), we show that habitat selection was important to explain space use by ibex. As a consequence, movement was constrained by habitat selection, as observed displacement rate was shorter than expected under null selection. Selection-independent movement, selection strength and resource availability were important drivers of seasonal home range size. Both displacement rate and directional persistence had a positive relationship with home range size while accounting for habitat selection, suggesting that individual characteristics and state may also affect home range size. Ibex living at higher altitudes, where resource availability shows stronger altitudinal gradients across the year, had larger home ranges. Home range size was larger in spring and autumn, when ibex ascend and descend back, and smaller in summer and winter, when resources are more stable. Therefore, home range size decreased with resource availability. Finally, males had larger home ranges than females, which might be explained by differences in body size and reproductive behaviour. Movement, selection strength, resource availability and intrinsic factors related to sex determined home range size of Iberian ibex. Our results highlight the need to integrate and account for process dependencies, here the interdependence of movement and habitat selection, to understand how animals use space. This study contributes to understand how movement links environmental and geographical space use and determines home range behaviour in large herbivores.
The GS (genetic selection) Principle.
Abel, David L
2009-01-01
The GS (Genetic Selection) Principle states that biological selection must occur at the nucleotide-sequencing molecular-genetic level of 3'5' phosphodiester bond formation. After-the-fact differential survival and reproduction of already-living phenotypic organisms (ordinary natural selection) does not explain polynucleotide prescription and coding. All life depends upon literal genetic algorithms. Even epigenetic and "genomic" factors such as regulation by DNA methylation, histone proteins and microRNAs are ultimately instructed by prior linear digital programming. Biological control requires selection of particular configurable switch-settings to achieve potential function. This occurs largely at the level of nucleotide selection, prior to the realization of any integrated biofunction. Each selection of a nucleotide corresponds to the setting of two formal binary logic gates. The setting of these switches only later determines folding and binding function through minimum-free-energy sinks. These sinks are determined by the primary structure of both the protein itself and the independently prescribed sequencing of chaperones. The GS Principle distinguishes selection of existing function (natural selection) from selection for potential function (formal selection at decision nodes, logic gates and configurable switch-settings).
Alexander, H J; Richardson, J M L; Anholt, B R
2014-09-01
Polygenic sex determination (PSD) is relatively rare and theoretically evolutionary unstable, yet has been reported across a range of taxa. Evidence for multilocus PSD is provided by (i) large between-family variance in sex ratio, (ii) paternal and maternal effects on family sex ratio and (iii) response to selection for family sex ratio. This study tests the polygenic hypothesis of sex determination in the harpacticoid copepod Tigriopus californicus using the criterion of response to selection. We report the first multigenerational quantitative evidence that clutch sex ratio responds to artificial selection in both directions (selection for male- and female-biased families) and in multiple populations of T. californicus. In the five of six lines that showed a response to selection, realized heritability estimated by multigenerational analysis ranged from 0.24 to 0.58. Divergence of clutch sex ratio between selection lines is rapid, with response to selection detectable within the first four generations of selection. © 2014 The Authors. Journal of Evolutionary Biology © 2014 European Society For Evolutionary Biology.
Determination of the cement content of hardened concrete by selective solution : final report.
DOT National Transportation Integrated Search
1972-01-01
The method of selective solution by methanolic maleic acid, developed by Tabikh et. al for the determination of cement content in hardened concrete, was evaluated. It was found to be relatively simple and inexpensive, and is accurate to within 1 pe...
A selective liquid pressurized extraction (SPLE) method was developed as a streamlined sample preparation/cleanup procedure for determining Aroclors and coplanar polychlorinated biphenyls (PCBs) in soil and sediment matrices. The SPLE method was coupled with an enzyme-linked imm...
What Determines Limb Selection for Reaching?
ERIC Educational Resources Information Center
Helbig, Casi Rabb; Gabbard, Carl
2004-01-01
While motor dominance appears to drive limb selection for reaching movements at the midline and ipsilateral (dominant) side, this study examined the possible determinants associated with what drives the programming of movements in response to stimuli presented in contralateral space. Experiment 1 distinguished between object proximity and a…
Tan, E L; Shah, H S; Leister, K J; Kozick, L M; Pasciak, P; Vanderlaan, R K; Yu, C D; Patel, B
1993-08-01
The selection of an ideal semisolid vehicle for growth factors presents a challenge. Some antimicrobial agents are known to delay wound healing. The objective of this investigation was to identify appropriate preservatives and vehicles for TGF-alpha. Criteria for acceptance are noninterference with the mitogenic activity of TGF-alpha as well as adequate product preservation. Vehicles considered were o/w creams, ointments, and a gel. Combinations of six preservatives were tested. Selection was determined using both microbial preservative challenge and TGF-alpha mitogenic assay. In the former, 10 species of microorganisms were inoculated into formulation samples. At selected time intervals, it was determined whether colonies decreased, increased, or remained constant. In the mitogenic assay, samples of either preservatives or formulation prototypes were introduced to TGF-alpha-stimulated fibroblast cell cultures. Mitogenesis was determined by measuring 3H-dThd uptake into newly synthesized DNA. As preservatives, sorbic acid and quaternium-15 appear to satisfy both selection criteria. A thermosetting gel appears most promising as vehicle.
Wang, Xianghong; Jiang, Daiming; Yang, Daichang
2015-01-01
The selection of homozygous lines is a crucial step in the characterization of newly generated transgenic plants. This is particularly time- and labor-consuming when transgenic stacking is required. Here, we report a fast and accurate method based on quantitative real-time PCR with a rice gene RBE4 as a reference gene for selection of homozygous lines when using multiple transgenic stacking in rice. Use of this method allowed can be used to determine the stacking of up to three transgenes within four generations. Selection accuracy reached 100 % for a single locus and 92.3 % for two loci. This method confers distinct advantages over current transgenic research methodologies, as it is more accurate, rapid, and reliable. Therefore, this protocol could be used to efficiently select homozygous plants and to expedite time- and labor-consuming processes normally required for multiple transgene stacking. This protocol was standardized for determination of multiple gene stacking in molecular breeding via marker-assisted selection.
Three-dimensional, position-sensitive radiation detection
He, Zhong; Zhang, Feng
2010-04-06
Disclosed herein is a method of determining a characteristic of radiation detected by a radiation detector via a multiple-pixel event having a plurality of radiation interactions. The method includes determining a cathode-to-anode signal ratio for a selected interaction of the plurality of radiation interactions based on electron drift time data for the selected interaction, and determining the radiation characteristic for the multiple-pixel event based on both the cathode-to-anode signal ratio and the electron drift time data. In some embodiments, the method further includes determining a correction factor for the radiation characteristic based on an interaction depth of the plurality of radiation interactions, a lateral distance between the selected interaction and a further interaction of the plurality of radiation interactions, and the lateral positioning of the plurality of radiation interactions.
A selective-update affine projection algorithm with selective input vectors
NASA Astrophysics Data System (ADS)
Kong, NamWoong; Shin, JaeWook; Park, PooGyeon
2011-10-01
This paper proposes an affine projection algorithm (APA) with selective input vectors, which based on the concept of selective-update in order to reduce estimation errors and computations. The algorithm consists of two procedures: input- vector-selection and state-decision. The input-vector-selection procedure determines the number of input vectors by checking with mean square error (MSE) whether the input vectors have enough information for update. The state-decision procedure determines the current state of the adaptive filter by using the state-decision criterion. As the adaptive filter is in transient state, the algorithm updates the filter coefficients with the selected input vectors. On the other hand, as soon as the adaptive filter reaches the steady state, the update procedure is not performed. Through these two procedures, the proposed algorithm achieves small steady-state estimation errors, low computational complexity and low update complexity for colored input signals.
Reliable Refuge: Two Sky Island Scorpion Species Select Larger, Thermally Stable Retreat Sites.
Becker, Jamie E; Brown, Christopher A
2016-01-01
Sky island scorpions shelter under rocks and other surface debris, but, as with other scorpions, it is unclear whether these species select retreat sites randomly. Furthermore, little is known about the thermal preferences of scorpions, and no research has been done to identify whether reproductive condition might influence retreat site selection. The objectives were to (1) identify physical or thermal characteristics for retreat sites occupied by two sky island scorpions (Vaejovis cashi Graham 2007 and V. electrum Hughes 2011) and those not occupied; (2) determine whether retreat site selection differs between the two study species; and (3) identify whether thermal selection differs between species and between gravid and non-gravid females of the same species. Within each scorpion's habitat, maximum dimensions of rocks along a transect line were measured and compared to occupied rocks to determine whether retreat site selection occurred randomly. Temperature loggers were placed under a subset of occupied and unoccupied rocks for 48 hours to compare the thermal characteristics of these rocks. Thermal gradient trials were conducted before parturition and after dispersal of young in order to identify whether gravidity influences thermal preference. Vaejovis cashi and V. electrum both selected larger retreat sites that had more stable thermal profiles. Neither species appeared to have thermal preferences influenced by reproductive condition. However, while thermal selection did not differ among non-gravid individuals, gravid V. electrum selected warmer temperatures than its gravid congener. Sky island scorpions appear to select large retreat sites to maintain thermal stability, although biotic factors (e.g., competition) could also be involved in this choice. Future studies should focus on identifying the various biotic or abiotic factors that could influence retreat site selection in scorpions, as well as determining whether reproductive condition affects thermal selection in other arachnids.
Neltner, Thomas G; Alger, Heather M; O'Reilly, James T; Krimsky, Sheldon; Bero, Lisa A; Maffini, Maricel V
Food and Drug Administration (FDA) guidance allows food manufacturers to determine whether additives to food are "generally recognized as safe" (GRAS). Manufacturers are not required to notify the FDA of a GRAS determination, although in some instances they notify the agency. The individuals that companies select to make these determinations may have financial conflicts of interest. To determine the extent to which individuals selected by manufacturers to make GRAS determinations have conflicts of interest between their obligations to ensure that the use of the additive is safe and their financial relationships to the company. DESIGN Using conflict of interest criteria developed by a committee of the Institute of Medicine, we analyzed 451 GRAS notifications that were voluntarily submitted to the FDA between 1997 and 2012. Number of GRAS notices submitted to the FDA; frequency of various types of relationships between decision maker and additive manufacturer; frequency of participation on GRAS panels by individuals; and number of GRAS safety determinations identified by the FDA that were not submitted to the agency. For the 451 GRAS notifications, 22.4% of the safety assessments were made by an employee of an additive manufacturer, 13.3% by an employee of a consulting firm selected by the manufacturer, and 64.3% by an expert panel selected by either a consulting firm or the manufacturer. A standing expert panel selected by a third party made none of these safety assessments. The 290 panels that made GRAS determinations had an average of 3.5 members, with a maximum of 7. Ten individuals served on 27 or more panels; 1 individual served on 128 panels (44.1%). At least 1 of the 10 individuals with the most frequent service was a member of 225 panels (77.6%). Between 1997 and 2012, financial conflicts of interest were ubiquitous in determinations that an additive to food was GRAS. The lack of independent review in GRAS determinations raises concerns about the integrity of the process and whether it ensures the safety of the food supply, particularly in instances where the manufacturer does not notify the FDA of the determination. The FDA should address these concerns.
On the maintenance of sex chromosome polymorphism by sex-antagonistic selection.
Blaser, Olivier; Neuenschwander, Samuel; Perrin, Nicolas
2011-10-01
Complex sex determination systems are a priori unstable and require specific selective forces for their maintenance. Analytical derivations suggest that sex antagonistic selection may play such a role, but this assumes absence of recombination between the sex-determining and sex-antagonistic genes. Using individual-based simulations and focusing on the sex chromosome and coloration polymorphisms of platy fishes as a case study, we show that the conditions for polymorphism maintenance induce female biases in primary sex ratios, so that sex ratio selection makes the system collapse toward male or female heterogamety as soon as recombinant genotypes appear. However, a polymorphism can still be maintained under scenarios comprising strong sexual selection against dull males, mild natural selection against bright females, and low recombination rates. Though such conditions are plausibly met in natural populations of fishes harboring such polymorphisms, quantitative empirical evaluations are required to properly test whether sex antagonistic selection is a causal agent or whether other selective processes are required (such as local mate competition favoring female-biased sex ratios).
[Measurement of Water COD Based on UV-Vis Spectroscopy Technology].
Wang, Xiao-ming; Zhang, Hai-liang; Luo, Wei; Liu, Xue-mei
2016-01-01
Ultraviolet/visible (UV/Vis) spectroscopy technology was used to measure water COD. A total of 135 water samples were collected from Zhejiang province. Raw spectra with 3 different pretreatment methods (Multiplicative Scatter Correction (MSC), Standard Normal Variate (SNV) and 1st Derivatives were compared to determine the optimal pretreatment method for analysis. Spectral variable selection is an important strategy in spectrum modeling analysis, because it tends to parsimonious data representation and can lead to multivariate models with better performance. In order to simply calibration models, the preprocessed spectra were then used to select sensitive wavelengths by competitive adaptive reweighted sampling (CARS), Random frog and Successive Genetic Algorithm (GA) methods. Different numbers of sensitive wavelengths were selected by different variable selection methods with SNV preprocessing method. Partial least squares (PLS) was used to build models with the full spectra, and Extreme Learning Machine (ELM) was applied to build models with the selected wavelength variables. The overall results showed that ELM model performed better than PLS model, and the ELM model with the selected wavelengths based on CARS obtained the best results with the determination coefficient (R2), RMSEP and RPD were 0.82, 14.48 and 2.34 for prediction set. The results indicated that it was feasible to use UV/Vis with characteristic wavelengths which were obtained by CARS variable selection method, combined with ELM calibration could apply for the rapid and accurate determination of COD in aquaculture water. Moreover, this study laid the foundation for further implementation of online analysis of aquaculture water and rapid determination of other water quality parameters.
Telschow, K.L.; Siu, B.K.
1996-07-09
A method of evaluating integrity of adherence of a conductor bond to a substrate includes: (a) impinging a plurality of light sources onto a substrate; (b) detecting optical reflective signatures emanating from the substrate from the impinged light; (c) determining location of a selected conductor bond on the substrate from the detected reflective signatures; (d) determining a target site on the selected conductor bond from the detected reflective signatures; (e) optically imparting an elastic wave at the target site through the selected conductor bond and into the substrate; (f) optically detecting an elastic wave signature emanating from the substrate resulting from the optically imparting step; and (g) determining integrity of adherence of the selected conductor bond to the substrate from the detected elastic wave signature emanating from the substrate. A system is disclosed which is capable of conducting the method. 13 figs.
Telschow, Kenneth L.; Siu, Bernard K.
1996-01-01
A method of evaluating integrity of adherence of a conductor bond to a substrate includes: a) impinging a plurality of light sources onto a substrate; b) detecting optical reflective signatures emanating from the substrate from the impinged light; c) determining location of a selected conductor bond on the substrate from the detected reflective signatures; d) determining a target site on the selected conductor bond from the detected reflective signatures; e) optically imparting an elastic wave at the target site through the selected conductor bond and into the substrate; f) optically detecting an elastic wave signature emanating from the substrate resulting from the optically imparting step; and g) determining integrity of adherence of the selected conductor bond to the substrate from the detected elastic wave signature emanating from the substrate. A system is disclosed which is capable of conducting the method.
Careau, Vincent; Wolak, Matthew E.; Carter, Patrick A.; Garland, Theodore
2015-01-01
Given the pace at which human-induced environmental changes occur, a pressing challenge is to determine the speed with which selection can drive evolutionary change. A key determinant of adaptive response to multivariate phenotypic selection is the additive genetic variance–covariance matrix (G). Yet knowledge of G in a population experiencing new or altered selection is not sufficient to predict selection response because G itself evolves in ways that are poorly understood. We experimentally evaluated changes in G when closely related behavioural traits experience continuous directional selection. We applied the genetic covariance tensor approach to a large dataset (n = 17 328 individuals) from a replicated, 31-generation artificial selection experiment that bred mice for voluntary wheel running on days 5 and 6 of a 6-day test. Selection on this subset of G induced proportional changes across the matrix for all 6 days of running behaviour within the first four generations. The changes in G induced by selection resulted in a fourfold slower-than-predicted rate of response to selection. Thus, selection exacerbated constraints within G and limited future adaptive response, a phenomenon that could have profound consequences for populations facing rapid environmental change. PMID:26582016
Federal Register 2010, 2011, 2012, 2013, 2014
2011-07-29
... DEPARTMENT OF STATE [Public Notice: 7540] Culturally Significant Objects Imported for Exhibition Determinations: ``5,000 Years of Chinese Jade Featuring Selections From the National Museum of Taiwan and the... ``5,000 Years of Chinese Jade Featuring Selections from the National Museum of Taiwan and the Arthur M...
Chocholik, Joan K.; Bouchard, Susan E.; Tan, Joseph K. H.; Ostrow, David N.
1999-01-01
Objectives: To determine the relevant weighted goals and criteria for use in the selection of an automated patient care information system (PCIS) using a modified Delphi technique to achieve consensus. Design: A three-phase, six-round modified Delphi process was implemented by a ten-member PCIS selection task force. The first phase consisted of an exploratory round. It was followed by the second phase, of two rounds, to determine the selection goals and finally the third phase, of three rounds, to finalize the selection criteria. Results: Consensus on the goals and criteria for selecting a PCIS was measured during the Delphi process by reviewing the mean and standard deviation of the previous round's responses. After the study was completed, the results were analyzed using a limits-of-agreement indicator that showed strong agreement of each individual's responses between each of the goal determination rounds. Further analysis for variability in the group's response showed a significant movement to consensus after the first goal-determination iteration, with consensus reached on all goals by the end of the second iteration. Conclusion: The results indicated that the relevant weighted goals and criteria used to make the final decision for an automated PCIS were developed as a result of strong agreement among members of the PCIS selection task force. It is therefore recognized that the use of the Delphi process was beneficial in achieving consensus among clinical and nonclinical members in a relatively short time while avoiding a decision based on political biases and the “groupthink” of traditional committee meetings. The results suggest that improvements could be made in lessening the number of rounds by having information available through side conversations, by having other statistical indicators besides the mean and standard deviation available between rounds, and by having a content expert address questions between rounds. PMID:10332655
Sex determination based on a thoracic vertebra and ribs evaluation using clinical chest radiography.
Tsubaki, Shun; Morishita, Junji; Usumoto, Yosuke; Sakaguchi, Kyoko; Matsunobu, Yusuke; Kawazoe, Yusuke; Okumura, Miki; Ikeda, Noriaki
2017-07-01
Our aim was to investigate whether sex can be determined from a combination of geometric features obtained from the 10th thoracic vertebra, 6th rib, and 7th rib. Six hundred chest radiographs (300 males and 300 females) were randomly selected to include patients of six age groups (20s, 30s, 40s, 50s, 60s, and 70s). Each group included 100 images (50 males and 50 females). A total of 14 features, including 7 lengths, 5 indices for the vertebra, and 2 types of widths for ribs, were utilized and analyzed for sex determination. Dominant features contributing to sex determination were selected by stepwise discriminant analysis after checking the variance inflation factors for multicollinearity. The accuracy of sex determination using a combination of the vertebra and ribs was evaluated from the selected features by the stepwise discriminant analysis. The accuracies in each age group were also evaluated in this study. The accuracy of sex determination based on a combination of features of the vertebra and ribs was 88.8% (533/600). This performance was superior to that of the vertebra or ribs only. Moreover, sex determination of subjects in their 20s demonstrated the highest accuracy (96.0%, 96/100). The features selected in the stepwise discriminant analysis included some features in both the vertebra and ribs. These results indicate the usefulness of combined information obtained from the vertebra and ribs for sex determination. We conclude that a combination of geometric characteristics obtained from the vertebra and ribs could be useful for determining sex. Copyright © 2017 Elsevier B.V. All rights reserved.
Selecting the Administrative Computing Executive.
ERIC Educational Resources Information Center
Bielec, John A.
1985-01-01
Important steps in the computing administrator selection process are outlined, including: reviewing the administrative computing organization, determining a search methodology, selecting a search or screening committee, narrowing the candidate pool, scheduling interviews and evaluating candidates, and conducting negotiations. (MSE)
The (Un)Certainty of Selectivity in Liquid Chromatography Tandem Mass Spectrometry
NASA Astrophysics Data System (ADS)
Berendsen, Bjorn J. A.; Stolker, Linda A. M.; Nielen, Michel W. F.
2013-01-01
We developed a procedure to determine the "identification power" of an LC-MS/MS method operated in the MRM acquisition mode, which is related to its selectivity. The probability of any compound showing the same precursor ion, product ions, and retention time as the compound of interest is used as a measure of selectivity. This is calculated based upon empirical models constructed from three very large compound databases. Based upon the final probability estimation, additional measures to assure unambiguous identification can be taken, like the selection of different or additional product ions. The reported procedure in combination with criteria for relative ion abundances results in a powerful technique to determine the (un)certainty of the selectivity of any LC-MS/MS analysis and thus the risk of false positive results. Furthermore, the procedure is very useful as a tool to validate method selectivity.
NASA Technical Reports Server (NTRS)
Heine, John J. (Inventor); Clarke, Laurence P. (Inventor); Deans, Stanley R. (Inventor); Stauduhar, Richard Paul (Inventor); Cullers, David Kent (Inventor)
2001-01-01
A system and method for analyzing a medical image to determine whether an abnormality is present, for example, in digital mammograms, includes the application of a wavelet expansion to a raw image to obtain subspace images of varying resolution. At least one subspace image is selected that has a resolution commensurate with a desired predetermined detection resolution range. A functional form of a probability distribution function is determined for each selected subspace image, and an optimal statistical normal image region test is determined for each selected subspace image. A threshold level for the probability distribution function is established from the optimal statistical normal image region test for each selected subspace image. A region size comprising at least one sector is defined, and an output image is created that includes a combination of all regions for each selected subspace image. Each region has a first value when the region intensity level is above the threshold and a second value when the region intensity level is below the threshold. This permits the localization of a potential abnormality within the image.
Evaluation and selection of 3PL provider using fuzzy AHP and grey TOPSIS in group decision making
NASA Astrophysics Data System (ADS)
Garside, Annisa Kesy; Saputro, Thomy Eko
2017-11-01
Selection of a 3PL provider is a problem of multi criteria decision making, where the decision maker has to select several 3PL provider alternatives based on several evaluation criteria. A decision maker will have difficulty to express judgments in exact numerical values due to the fact that information is often incomplete and the decision environment is uncertain. This paper presents an integrated fuzzy AHP and Grey TOPSIS for the evaluation and selection of 3PL provider method. Fuzzy AHP is used to determine the importance weight of evaluation criteria. For final selection, grey TOPSIS is used to evaluate the alternatives and obtain the overall performance which is measured as closeness coefficient. This method is applied to solve the selection of 3PL provider at PT. X. Five criterias and twelve sub-criterias were determined and then the best alternative among four 3PL providers was selected by proposed method.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Giner, Emmanuel; Scemama, Anthony; Caffarel, Michel
2015-01-28
The potential energy curve of the F{sub 2} molecule is calculated with Fixed-Node Diffusion Monte Carlo (FN-DMC) using Configuration Interaction (CI)-type trial wavefunctions. To keep the number of determinants reasonable and thus make FN-DMC calculations feasible in practice, the CI expansion is restricted to those determinants that contribute the most to the total energy. The selection of the determinants is made using the CIPSI approach (Configuration Interaction using a Perturbative Selection made Iteratively). The trial wavefunction used in FN-DMC is directly issued from the deterministic CI program; no Jastrow factor is used and no preliminary multi-parameter stochastic optimization of themore » trial wavefunction is performed. The nodes of CIPSI wavefunctions are found to reduce significantly the fixed-node error and to be systematically improved upon increasing the number of selected determinants. To reduce the non-parallelism error of the potential energy curve, a scheme based on the use of a R-dependent number of determinants is introduced. Using Dunning’s cc-pVDZ basis set, the FN-DMC energy curve of F{sub 2} is found to be of a quality similar to that obtained with full configuration interaction/cc-pVQZ.« less
Kryzanowski, Julie A; McIntyre, Lynn
2011-01-01
Mainstream environmental assessment (EA) methodologies often inadequately address health, social and cultural impacts of concern for Canadian indigenous communities affected by industrialization. Our objective is to present a holistic, culturally-appropriate framework for the selection of indigenous health indicators for baseline health assessment, impact prediction, or monitoring of impacts over time. We used a critical population health approach to explore the determinants of health and health inequities in indigenous communities and conceptualize the pathways by which industrialization affects these determinants. We integrated and extended key elements from three indigenous health frameworks into a new holistic model for the selection of indigenous EA indicators. The holistic model conceptualizes individual and community determinants of health within external social, economic and political contexts and thus provides a comprehensive framework for selecting indicators of indigenous health. Indigenous health is the product of interactions among multiple determinants of health and contexts. Potential applications are discussed using case study examples involving indigenous communities affected by industrialization. Industrialization can worsen indigenous health inequities by perpetuating the health, social and cultural impacts of historic environmental dispossession. To mitigate impacts, EA should explicitly recognize linkages between environmental dispossession and the determinants of health and health inequities and meaningfully involve indigenous communities in the process.
An Analysis of Illegibilities in the Cursive Handwriting of 1,000 Selected Sixth-Grade Students.
ERIC Educational Resources Information Center
Horton, Lowell Wayne
The purpose of this study was to collect and analyze specimens of cursive handwriting of 1,000 selected sixth grade students in an attempt to determine analytically how sex and handedness differences affected cursive handwriting. Specifically, an attempt was made to determine those particular letters or letter combinations which were illegible…
1.1. This is a gas chromatography/mass spectrometry (GC/MS) method for the determination of selected semivolatile organic compounds in drinking waters. Accuracy and precision data have been generated in reagent water, and in finished ground and surface waters for the compounds li...
Children's Reasons and Motivations for the Selection of Favorite Books.
ERIC Educational Resources Information Center
Lawson, Cornelia V.
The twofold purpose of this study was to determine the reasons and motivations for the choice of favorite books made by fifth grade children and to determine whether teachers and librarians were able to identify the reasons influencing the children in this selection. Results showed that primary interest areas were animals, mystery and ghost…
2015-01-01
The origin of selectivity in the α-fluorination of cyclic ketones catalyzed by cinchona alkaloid-derived primary amines is determined with density functional calculations. The chair preference of a seven-membered ring at the fluorine transfer transition state is key in determining the sense and level of enantiofacial selectivity. PMID:24967514
Determination of coronal magnetic fields from vector magnetograms
NASA Technical Reports Server (NTRS)
Mikic, Zoran
1992-01-01
The determination of coronal magnetic fields from vector magnetograms, including the development and application of algorithms to determine force-free coronal fields above selected observations of active regions is studied. Two additional active regions were selected and analyzed. The restriction of periodicity in the 3-D code which is used to determine the coronal field was removed giving the new code variable mesh spacing and is thus able to provide a more realistic description of coronal fields. The NOAA active region AR5747 of 20 Oct. 1989 was studied. A brief account of progress during the research performed is reported.
Lysine and the Na+/K+ Selectivity in Mammalian Voltage-Gated Sodium Channels.
Li, Yang; Liu, Huihui; Xia, Mengdie; Gong, Haipeng
2016-01-01
Voltage-gated sodium (Nav) channels are critical in the generation and transmission of neuronal signals in mammals. The crystal structures of several prokaryotic Nav channels determined in recent years inspire the mechanistic studies on their selection upon the permeable cations (especially between Na+ and K+ ions), a property that is proposed to be mainly determined by residues in the selectivity filter. However, the mechanism of cation selection in mammalian Nav channels lacks direct explanation at atomic level due to the difference in amino acid sequences between mammalian and prokaryotic Nav homologues, especially at the constriction site where the DEKA motif has been identified to determine the Na+/K+ selectivity in mammalian Nav channels but is completely absent in the prokaryotic counterparts. Among the DEKA residues, Lys is of the most importance since its mutation to Arg abolishes the Na+/K+ selectivity. In this work, we modeled the pore domain of mammalian Nav channels by mutating the four residues at the constriction site of a prokaryotic Nav channel (NavRh) to DEKA, and then mechanistically investigated the contribution of Lys in cation selection using molecular dynamics simulations. The DERA mutant was generated as a comparison to understand the loss of ion selectivity caused by the K-to-R mutation. Simulations and free energy calculations on the mutants indicate that Lys facilitates Na+/K+ selection by electrostatically repelling the cation to a highly Na+-selective location sandwiched by the carboxylate groups of Asp and Glu at the constriction site. In contrast, the electrostatic repulsion is substantially weakened when Lys is mutated to Arg, because of two intrinsic properties of the Arg side chain: the planar geometric design and the sparse charge distribution of the guanidine group.
Effects of selection for decreased residual feed intake on composition and quality of fresh pork.
Smith, R M; Gabler, N K; Young, J M; Cai, W; Boddicker, N J; Anderson, M J; Huff-Lonergan, E; Dekkers, J C M; Lonergan, S M
2011-01-01
The objectives of this study were to determine the extent to which selection for decreased residual feed intake (RFI) affects pork composition and quality. Pigs from the fifth generation of selection for decreased RFI (select) and a randomly selected line (control) were utilized. Two experiments were conducted. In Exp. 1, barrows (22.6 ± 3.9 kg) from select and control lines were paired based on age and BW. The test was conducted in 8 replicates of pairs for the test period of 6 wk. Calpastatin activity and myosin isoforms profile were determined on samples from the LM. Control barrows were heavier (59.1 vs. 55.0 kg; P < 0.01) at the end of the test period. Calpastatin activity was greater (P < 0.01) in LM of select barrows than control barrows. In Exp. 2, composition and quality of gilts (114 kg) from control and select lines were determined. The model included fixed effects of line, slaughter date, melanocortin-4 receptor (MC4R) genotype, barn group, line × slaughter date, genotype × line interactions, a covariate of off-test BW, and sire, pen, and litter fitted as random effects. The select line (n = 80) had 0.043 kg less (P < 0.05) RFI per day than the control line (n = 89). Loin quality and composition were determined at 2 d postmortem. Desmin degradation was measured at 2 and 7 d postmortem. Purge, cook loss, sensory traits, and star probe texture were measured at 7 to 10 d postmortem on cooked chops. Residual correlations between RFI and composition and quality traits were calculated. Compared with the control line, carcasses from the select line tended to have less (P = 0.09) backfat, greater (P < 0.05) loin depth, and greater (P < 0.05) fat free lean. Loin chops from the select line had less (P < 0.01) intramuscular lipid content than loin chops from control line. Significant residual correlations between RFI and both tenderness (r = 0.24, P < 0.01) and star probe (r = -0.26, P < 0.01) were identified. Selection for decreased RFI has the potential to improve carcass composition with few effects on pH and water-holding capacity. However, decreased RFI could negatively affect tenderness and texture because of decreased lipid content and decreased postmortem protein degradation.
Sawdy, R J; Slater, D M; Dennes, W J; Sullivan, M H; Bennett, P R
2000-01-01
The aim of this study was to determine the relative contributions of cyclo-oxygenase (COX) types 1 and 2 to prostaglandin synthesis at term. Fetal membranes were collected from 6 pregnancies after elective caesarean section at term, prior to labour. The presence of COX-1 and COX-2 protein was determined using Western analysis. The relative contributions of the two isoforms of COX to prostaglandin synthesis were determined by incubation of fetal membrane discs with either a COX-2 selective inhibitor, SC236, or a COX-1 selective inhibitor, SC560, and measurement of prostaglandin release during 24 h using enzyme-linked immuno-sorbent assay (ELISA). Both COX-1 and COX-2 protein were demonstrated in amnion and chorion-decidua. The COX-2 selective inhibitor, SC-236, significantly reduced prostaglandin synthesis, both in its COX-2 specific and higher, non-specific concentration ranges. The COX-1 selective inhibitor, SC-560, had no effect upon prostaglandin synthesis in its COX-1 specific concentration range, but did significantly reduce prostaglandin synthesis at higher, non-selective concentrations. Fetal membranes contain both COX-1 and COX-2 at term, but only COX-2 contributes towards prostaglandin synthesis. COX-2 selective NSAI drugs will be as effective as non-selective agents in inhibition of fetal membrane prostaglandin synthesis and may represent a new strategy for tocolysis. Copyright 2000 Harcourt Publishers Ltd.
Reproducibility of CT bone densitometry: operator versus automated ROI definition.
Louis, O; Luypaert, R; Kalender, W; Osteaux, M
1988-05-01
Intrasubject reproducibility with repeated determination of vertebral mineral density from a given set of CT images was investigated. The region of interest (ROI) in 10 patient scans was selected by four independent operators either manually or with an automated procedure separating cortical and spongeous bone, the operators being requested to interact in ROI selection. The mean intrasubject variation was found to be much lower with the automated process (0.3 to 0.6%) than with the conventional method (2.5 to 5.2%). In a second study, 10 patients were examined twice to determine the reproducibility of CT slice selection by the operator. The errors were of the same order of magnitude as in ROI selection.
Tuning the ion selectivity of tetrameric cation channels by changing the number of ion binding sites
DOE Office of Scientific and Technical Information (OSTI.GOV)
Derebe, Mehabaw G.; Sauer, David B.; Zeng, Weizhong
2015-11-30
Selective ion conduction across ion channel pores is central to cellular physiology. To understand the underlying principles of ion selectivity in tetrameric cation channels, we engineered a set of cation channel pores based on the nonselective NaK channel and determined their structures to high resolution. These structures showcase an ensemble of selectivity filters with a various number of contiguous ion binding sites ranging from 2 to 4, with each individual site maintaining a geometry and ligand environment virtually identical to that of equivalent sites in K{sup +} channel selectivity filters. Combined with single channel electrophysiology, we show that only themore » channel with four ion binding sites is K{sup +} selective, whereas those with two or three are nonselective and permeate Na{sup +} and K{sup +} equally well. These observations strongly suggest that the number of contiguous ion binding sites in a single file is the key determinant of the channel's selectivity properties and the presence of four sites in K{sup +} channels is essential for highly selective and efficient permeation of K{sup +} ions.« less
Lutka, Anna; Maruszewska, Małgorzata
2011-01-01
It were established and validated the conditions of voltammetric determination of copper in pharmaceutical preparations. The three selected preparations: Zincuprim (A), Wapń, cynk, miedź z wit. C (B), Vigor complete (V) contained different salts and different quantity of copper (II) and increasing number of accompanied ingredients. For the purpose to transfer copper into solution, the samples of powdered tablets of the first and second preparation were undergone extraction and of the third the mineralization procedures. The concentration of copper in solution was determined by differential pulse voltammetry (DP) using comparison with standard technique. In the validation process, the selectivity, accuracy, precision and linearity of DP determination of copper in three preparations were estimated. Copper was determined within the concentration range of 1-9 ppm (1-9 microg/mL): the mean recoveries approached 102% (A), 100% (B), 102% (V); the relative standard deviations of determinations (RSD) were 0.79-1.59% (A), 0.62-0.85% (B) and 1.68-2.28% (V), respectively. The mean recoveries and the RSDs of determination satisfied the requirements for the analyte concentration at the level 1-10 ppm. The statistical verification confirmed that the tested voltammetric method is suitable for determination of copper in pharmaceutical preparation.
Successful Air Force Source Selections Start with an Effective Empowered Team
responsibilities of the team that will conduct a source selection, there is less guidance and focus how to create an effective source selection team and...empower that team to successfully complete a source selection. This purpose of this research was to determine if an increased focus on the formation and...empowerment of source selection teams and not just processes and procedures contribute to the efficiency and success of Air Force source selections
Careau, Vincent; Wolak, Matthew E; Carter, Patrick A; Garland, Theodore
2015-11-22
Given the pace at which human-induced environmental changes occur, a pressing challenge is to determine the speed with which selection can drive evolutionary change. A key determinant of adaptive response to multivariate phenotypic selection is the additive genetic variance-covariance matrix ( G: ). Yet knowledge of G: in a population experiencing new or altered selection is not sufficient to predict selection response because G: itself evolves in ways that are poorly understood. We experimentally evaluated changes in G: when closely related behavioural traits experience continuous directional selection. We applied the genetic covariance tensor approach to a large dataset (n = 17 328 individuals) from a replicated, 31-generation artificial selection experiment that bred mice for voluntary wheel running on days 5 and 6 of a 6-day test. Selection on this subset of G: induced proportional changes across the matrix for all 6 days of running behaviour within the first four generations. The changes in G: induced by selection resulted in a fourfold slower-than-predicted rate of response to selection. Thus, selection exacerbated constraints within G: and limited future adaptive response, a phenomenon that could have profound consequences for populations facing rapid environmental change. © 2015 The Author(s).
Glenn, David F.; Matthern, Gretchen E.; Propp, W. Alan; Glenn, Anne W.; Shaw, Peter G.
2006-08-08
A method and apparatus for determining spatial locations of defects in a material are described. The method includes providing a plurality of electrodes in contact with a material, applying a sinusoidal voltage to a select number of the electrodes at a predetermined frequency, determining gain and phase angle measurements at other of the electrodes in response to applying the sinusoidal voltage to the select number of electrodes, determining impedance values from the gain and phase angle measurements, computing an impedance spectrum for an area of the material from the determined impedance values, and comparing the computed impedance spectrum with a known impedance spectrum to identify spatial locations of defects in the material.
1990-01-01
Titers 31 1. Collection of samples 31 2. Enzyme-linkedimmunosorbent assay 31 B. Development of Dot-Blot Assay 32 1. Selection of en2yme-sUbstrate system...ELISA results 39 2., Selection -of appropriate serum dilution 46 3. Selection -of appropriate antigen diltion 59 4. Selection of blockina concentration 64 5... Selection of incubation time for antibody-containing 65 fluid .6. Selection -of enn’me Conitumate reation. time . 6 7. Selection of svbstrate
Howard, David M; Pong-Wong, Ricardo; Knap, Pieter W; Kremer, Valentin D; Woolliams, John A
2018-05-10
Optimal contributions selection (OCS) provides animal breeders with a framework for maximising genetic gain for a predefined rate of inbreeding. Simulation studies have indicated that the source of the selective advantage of OCS is derived from breeding decisions being more closely aligned with estimates of Mendelian sampling terms ([Formula: see text]) of selection candidates, rather than estimated breeding values (EBV). This study represents the first attempt to assess the source of the selective advantage provided by OCS using a commercial pig population and by testing three hypotheses: (1) OCS places more emphasis on [Formula: see text] compared to EBV for determining which animals were selected as parents, (2) OCS places more emphasis on [Formula: see text] compared to EBV for determining which of those parents were selected to make a long-term genetic contribution (r), and (3) OCS places more emphasis on [Formula: see text] compared to EBV for determining the magnitude of r. The population studied also provided an opportunity to investigate the convergence of r over time. Selection intensity limited the number of males available for analysis, but females provided some evidence that the selective advantage derived from applying an OCS algorithm resulted from greater weighting being placed on [Formula: see text] during the process of decision-making. Male r were found to converge initially at a faster rate than female r, with approximately 90% convergence achieved within seven generations across both sexes. This study of commercial data provides some support to results from theoretical and simulation studies that the source of selective advantage from OCS comes from [Formula: see text]. The implication that genomic selection (GS) improves estimation of [Formula: see text] should allow for even greater genetic gains for a predefined rate of inbreeding, once the synergistic benefits of combining OCS and GS are realised.
NASA Technical Reports Server (NTRS)
Curley, Michael J. (Inventor); Sarkisov, Sergey S. (Inventor)
2008-01-01
A refractometer computer controls the rotation of a rotary plate upon which are mounted a prism optically coupled via an optical window to a spectroscopic cell holding a resin exhibiting a dynamic refractive index during photocuring. The computer system positions the prism and spectroscopic cell relative to a visible light laser which illuminates the prism-resin interface at selected incidence angles. A photodetector mounted on the plate generates a signal to the computer proportional to intensity of an internally reflected light beam. A curing light is selectively transmitted through the prism and into the photocurable resin. The refractometer determines the intensity of the internally reflected beam a selected incidence angles and determines the effective refractive index curve of the resin at an uncured state and, optionally, at a completely cured state. Next, an amount of uncured resin and selected optical components to be joined by the resin is placed in the spectroscopic cell and irradiated with the UV light. The refractometer is fixed at a selected incidence angle and measures the intensity of an internally reflected light beam of light throughout the cure cycle. The refractometer determines the resin's refractive index of the polymeric mixture by means of extrapolation of a horizontal shift in the effective refractive index curve of the resin from an uncured state to a selected point in the cure cycle.
7 CFR 2201.18 - Application selection.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 7 Agriculture 15 2010-01-01 2010-01-01 false Application selection. 2201.18 Section 2201.18 Agriculture Regulations of the Department of Agriculture (Continued) LOCAL TELEVISION LOAN GUARANTEE BOARD... selection. (a) Application Priority. When evaluating applications to determine which Project or combinations...
Kanadhia, Kirti C; Ramavataram, Divvi Venkata Subrahmanya Shri; Nilakhe, Shreeyas Prasad Dhanpal; Patel, Swati
2014-01-01
Various sources of drinking water, with varying levels of total hardness, and calcium and magnesium concentrations, are used by populations in different regions. The use of water purifiers can compound the problem of maintaining the desired levels of hardness. An inverse relationship between various conditions, including cardiovascular disease, and hard water has been reported. Until this study, investigation of the hardness of drinking water from different sources, and serum magnesium and calcium in normal subjects from the Surat district, had not been undertaken. This study was performed to assess the concentrations of calcium and magnesium, and total hardness in filtered and non-filtered water and the relationship with serum magnesium and calcium levels in normal subjects consuming such water. Three water samples were collected, at 15-day intervals, from 12 urban and rural areas of Surat; and also 10 different brands of bottled water. Samples were analyzed for total hardness and calcium by complexometric and EDTA methods respectively. Magnesium concentrations were obtained by subtraction of the calcium concentration from total hardness. Serum samples from healthy individuals were analyzed for magnesium and calcium using calmagite and arsenazo methods respectively. The independent t-test was used to establish significance at a level of 95%. A p-value <0.05 was considered significant. Mean total hardness, and calcium and magnesium concentrations in non-filtered, rural tube-well water were much higher than in filtered water from the same area, and the magnesium concentrations were significantly higher (p = 0.038). Filtered urban municipal had lower hardness and concentrations of calcium and magnesium (p = 0.01) compared to corresponding non-filtered water. Significantly lower levels were observed in bottled water compared to rural and urban sources of water. Serum magnesium was significantly lower in the population who were consuming filtered water compared to those drinking non-filtered water (p<0.05). No such difference was observed for serum calcium. Hypomagnesemia correlates with lower magnesium concentrations in drinking water (both rural tube-well and urban municipal waters), which can be attributed to the use of water purifiers. Assuming that a person consumes two liters of drinking water per day, it is estimated that there is an average loss of 160 mg (79%) of magnesium from total waterborne magnesium levels as a result of the filtration of both rural and urban water supplies. Bottled water is too hardness as in calcium and magnesium concentrations.
Ji, Wenhua; Zhang, Mingming; Yan, Huijiao; Zhao, Hengqiang; Mu, Yan; Guo, Lanping; Wang, Xiao
2017-12-01
We describe a solid-phase extraction adsorbent based on molecularly imprinted polymers (MIPs), prepared with use of a mimic template. The MIPs were used for the selective extraction and determination of three chlorogenic acids as combined quality markers for Lonicera japonica and Lianhua qingwen granules. The morphologies and surface groups of the MIPs were assessed by scanning electron microscopy, Brunauer-Emmett-Teller surface area analysis, and Fourier transform infrared spectroscopy. The adsorption isotherms, kinetics, and selectivity of the MIPs were systematically compared with those of non-molecularly imprinted polymers. The MIPs showed high selectivity toward three structurally similar chlorogenic acids (chlorogenic acid, cryptochlorogenic acid, and neochlorogenic acid). A procedure using molecularly imprinted solid-phase extraction coupled with high-performance liquid chromatography was established for the determination of three chlorogenic acids from Lonicera japonica and Lianhua qingwen granules. The recoveries of the chlorogenic acids ranged from 93.1% to 101.4%. The limits of detection and limits of quantification for the three chlorogenic acids were 0.003 mg g -1 and 0.01 mg g -1 , respectively. The newly developed method is thus a promising technique for the enrichment and determination of chlorogenic acids from herbal medicines. Graphical Abstract Mimic molecularly imprinted polymers for the selective extraction of chlorogenic acids.
ERIC Educational Resources Information Center
Kleinert, Jane O'Regan; Harrison, Elizabeth; Mills, Karen Rose; Dueppen, Brittney M.; Trailor, Ann Michelle
2014-01-01
The purpose of this study was to analyze a large data base of self-selected/self-determined goals developed by students aged 7-21 that had developmental disabilities. Data included 288 goals developed by 205 students involved in the Kentucky Youth Advocacy Project. Students, teachers, Speech/Language pathologists and families utilized the Self…
ERIC Educational Resources Information Center
Benson, Shanelle R.
2010-01-01
Purpose. The purpose of this study was to determine, to what degree, African American teachers in five selected, urban charter schools in New York performed the historical roles of counselor, advocate, disciplinarian, surrogate parent, and role model in, to determine how African American Teachers perceived the importance of performing the…
Paternity and Nested-within-Family Marker Assisted Selection in Space Planted Red Clover Nurseries
USDA-ARS?s Scientific Manuscript database
Presented is a cost effective marker assisted selection methodology that utilizes individual plant phenotypes, seed production based knowledge of maternity, molecular marker determined paternity, and nested within halfsib family linkage relationships. Combining all above listed components, selection...
Selective Exposure to Televised Violence.
ERIC Educational Resources Information Center
Atkin, Charles; And Others
1979-01-01
Present the results of a study conducted to determine the correlation between children's selection of television programs and aggression. The regression analysis suggests that the relationship between viewing and aggression may be attributable to selective exposure rather than the reverse viewing-causes-aggression sequence. (Author/JVP)
NASA Technical Reports Server (NTRS)
Schipper, John F. (Inventor)
2009-01-01
A mobile pill transmitter system that moves through or adjacent to one or more organs in an animal's body and that provides signals from which the pill's present location and/or present angular orientation can be determined. The system also provides signals from which the present roll angle of the pill, about a selected axis, can be determined. When the location coordinates and the roll angle of the pill are within selected ranges, an aperture on the pill container releases a selected chemical into or onto the body. Optionally, the pill as it moves also provides a sequence of visually perceptible images; the times for image formation may correspond to times at which the pill transmitter system location or image satisfies one or at least four different criteria.
Blanca-Lopez, N; Perez-Alzate, D; Ruano, F; Garcimartin, M; de la Torre, V; Mayorga, C; Somoza, M L; Perkins, J; Blanca, M; Canto, M G; Torres, M J
2015-08-01
An increasing number of patients show immediate selective hypersensitivity reactions to clavulanic acid (CLV) and amoxicillin (AX), probably due to their increased prescription. The maintenance of this response should be established. To assess that the immediate hypersensitivity selective response to AX or to CLV is maintained after repeated administration of penicillin G (PG)/penicillin V (PV) and AX. Patients with proven immediate hypersensitivity to AX (Group A) or CLV (Group B) were included. Diagnosis was performed using skin tests with major and minor determinants of PG (PPL/MDM), AX and CLV and by drug provocation test (DPT) if required. Selectivity was established by confirming tolerance to PG/PV (Group A) and to PG/PV and AX (Group B). The maintenance of the selective response was verified by repeating DPT, 15 days after the initial investigation, with the same procedure. Of 51 patients, 78% belonged to Group A and 22% to Group B. Most had anaphylaxis. In Group A, 72% were skin test positive; 28% required DPT. In Group B, 63% were skin test positive; 37% required DPT. Only two AX-selective cases developed positive responses after re-provocation with PG/PV. No cases selective for CLV developed a positive response to PG, PV or AX. The selective response to AX appears consistent, and a response to penicillin determinants only develops in a minority of cases. For the case of CLV, the selective response appears not to be modified by exposure to penicillin determinants, meaning that patients with CLV allergy can take penicillin derivatives safely. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Figueroa Velez, Dario X.; Ellefsen, Kyle L.; Hathaway, Ethan R.; Carathedathu, Mathew C.
2017-01-01
The maturation of cortical parvalbumin-positive (PV) interneurons depends on the interaction of innate and experience-dependent factors. Dark-rearing experiments suggest that visual experience determines when broad orientation selectivity emerges in visual cortical PV interneurons. Here, using neural transplantation and in vivo calcium imaging of mouse visual cortex, we investigated whether innate mechanisms contribute to the maturation of orientation selectivity in PV interneurons. First, we confirmed earlier findings showing that broad orientation selectivity emerges in PV interneurons by 2 weeks after vision onset, ∼35 d after these cells are born. Next, we assessed the functional development of transplanted PV (tPV) interneurons. Surprisingly, 25 d after transplantation (DAT) and >2 weeks after vision onset, we found that tPV interneurons have not developed broad orientation selectivity. By 35 DAT, however, broad orientation selectivity emerges in tPV interneurons. Transplantation does not alter orientation selectivity in host interneurons, suggesting that the maturation of tPV interneurons occurs independently from their endogenous counterparts. Together, these results challenge the notion that the onset of vision solely determines when PV interneurons become broadly tuned. Our results reveal that an innate cortical mechanism contributes to the emergence of broad orientation selectivity in PV interneurons. SIGNIFICANCE STATEMENT Early visual experience and innate developmental programs interact to shape cortical circuits. Visual-deprivation experiments have suggested that the onset of visual experience determines when interneurons mature in the visual cortex. Here we used neuronal transplantation and cellular imaging of visual responses to investigate the maturation of parvalbumin-positive (PV) interneurons. Our results suggest that the emergence of broad orientation selectivity in PV interneurons is innately timed. PMID:28123018
Saad, Ahmed S; Abo-Talib, Nisreen F; El-Ghobashy, Mohamed R
2016-01-05
Different methods have been introduced to enhance selectivity of UV-spectrophotometry thus enabling accurate determination of co-formulated components, however mixtures whose components exhibit wide variation in absorptivities has been an obstacle against application of UV-spectrophotometry. The developed ratio difference at coabsorptive point method (RDC) represents a simple effective solution for the mentioned problem, where the additive property of light absorbance enabled the consideration of the two components as multiples of the lower absorptivity component at certain wavelength (coabsorptive point), at which their total concentration multiples could be determined, whereas the other component was selectively determined by applying the ratio difference method in a single step. Mixture of perindopril arginine (PA) and amlodipine besylate (AM) figures that problem, where the low absorptivity of PA relative to AM hinders selective spectrophotometric determination of PA. The developed method successfully determined both components in the overlapped region of their spectra with accuracy 99.39±1.60 and 100.51±1.21, for PA and AM, respectively. The method was validated as per the USP guidelines and showed no significant difference upon statistical comparison with reported chromatographic method. Copyright © 2015 Elsevier B.V. All rights reserved.
Willemsen-Seegers, Nicole; Uitdehaag, Joost C M; Prinsen, Martine B W; de Vetter, Judith R F; de Man, Jos; Sawa, Masaaki; Kawase, Yusuke; Buijsman, Rogier C; Zaman, Guido J R
2017-02-17
Target residence time (τ) has been suggested to be a better predictor of the biological activity of kinase inhibitors than inhibitory potency (IC 50 ) in enzyme assays. Surface plasmon resonance binding assays for 46 human protein and lipid kinases were developed. The association and dissociation constants of 80 kinase inhibitor interactions were determined. τ and equilibrium affinity constants (K D ) were calculated to determine kinetic selectivity. Comparison of τ and K D or IC 50 values revealed a strikingly different view on the selectivity of several kinase inhibitors, including the multi-kinase inhibitor ponatinib, which was tested on 10 different kinases. In addition, known pan-Aurora inhibitors resided much longer on Aurora B than on Aurora A, despite having comparable affinity for Aurora A and B. Furthermore, the γ/δ-selective PI3K inhibitor duvelisib and the δ-selective drug idelalisib had similar 20-fold selectivity for δ- over γ-isoform but duvelisib resided much longer on both targets. Copyright © 2016 Elsevier Ltd. All rights reserved.
Plasticizer Effects in the PVC Membrane of the Dibasic Phosphate Selective Electrode
Carey, Clifton
2016-01-01
The PVC membrane of an ion-selective electrode (ISE) sensitive to dibasic phosphate ions (HPO4-ISE) has not been optimized for maximum selectivity, sensitivity, and useable ISE lifetime and further work was necessary to improve its performance. Two areas of investigation are reported here: include the parameters for the lipophilicity of the plasticizer compound used and the amount of cyclic polyamine ionophore incorporated in the PVC membrane. Six candidate plasticizers with a range of lipophilicity were evaluated for their effect on the useable lifetime, sensitivity, and selectivity of the ISE against 13 different anions. Selectivity was determined by a modified fixed interferent method, sensitivity was determined without interferents, and the usable lifetime evaluated at the elapsed time where 50% of the HPO4-ISE failed (L50). The results show that choosing a plasticizer that has a lipophilicity similar to the ionophore's results in the best selectivity and sensitivity and the longest L50. PMID:27347487
Sharp, T G
1984-02-01
The study was designed to determine whether any one of seven selected variables or a combination of the variables is predictive of performance on the State Board Test Pool Examination. The selected variables studied were: high school grade point average (HSGPA), The University of Tennessee, Knoxville, College of Nursing grade point average (GPA), and American College Test Assessment (ACT) standard scores (English, ENG; mathematics, MA; social studies, SS; natural sciences, NSC; composite, COMP). Data utilized were from graduates of the baccalaureate program of The University of Tennessee, Knoxville, College of Nursing from 1974 through 1979. The sample of 322 was selected from a total population of 572. The Statistical Analysis System (SAS) was designed to accomplish analysis of the predictive relationship of each of the seven selected variables to State Board Test Pool Examination performance (result of pass or fail), a stepwise discriminant analysis was designed for determining the predictive relationship of the strongest combination of the independent variables to overall State Board Test Pool Examination performance (result of pass or fail), and stepwise multiple regression analysis was designed to determine the strongest predictive combination of selected variables for each of the five subexams of the State Board Test Pool Examination. The selected variables were each found to be predictive of SBTPE performance (result of pass or fail). The strongest combination for predicting SBTPE performance (result of pass or fail) was found to be GPA, MA, and NSC.
Flammability Parameters of Candles
NASA Astrophysics Data System (ADS)
Balog, Karol; Kobetičová, Hana; Štefko, Tomáš
2017-06-01
The paper deals with the assessment of selected fire safety characteristics of candles. Weight loss of a candle during the burning process, candle burning rate, soot index, heat release rate and yield of carbon oxides were determined. Soot index was determined according to EN 15426: 2007 - Candles - Specification for Sooting Behavior. All samples met the prescribed amount of produced soot. Weight loss, heat release rate and the yield of carbon oxides were determined for one selected sample. While yield of CO increased during the measurement, the yield of CO2 decreased by half in 40 minutes.
Site-Selection in Single-Molecule Junction for Highly Reproducible Molecular Electronics.
Kaneko, Satoshi; Murai, Daigo; Marqués-González, Santiago; Nakamura, Hisao; Komoto, Yuki; Fujii, Shintaro; Nishino, Tomoaki; Ikeda, Katsuyoshi; Tsukagoshi, Kazuhito; Kiguchi, Manabu
2016-02-03
Adsorption sites of molecules critically determine the electric/photonic properties and the stability of heterogeneous molecule-metal interfaces. Then, selectivity of adsorption site is essential for development of the fields including organic electronics, catalysis, and biology. However, due to current technical limitations, site-selectivity, i.e., precise determination of the molecular adsorption site, remains a major challenge because of difficulty in precise selection of meaningful one among the sites. We have succeeded the single site-selection at a single-molecule junction by performing newly developed hybrid technique: simultaneous characterization of surface enhanced Raman scattering (SERS) and current-voltage (I-V) measurements. The I-V response of 1,4-benzenedithiol junctions reveals the existence of three metastable states arising from different adsorption sites. Notably, correlated SERS measurements show selectivity toward one of the adsorption sites: "bridge sites". This site-selectivity represents an essential step toward the reliable integration of individual molecules on metallic surfaces. Furthermore, the hybrid spectro-electric technique reveals the dependence of the SERS intensity on the strength of the molecule-metal interaction, showing the interdependence between the optical and electronic properties in single-molecule junctions.
USDA-ARS?s Scientific Manuscript database
The objective of this study was to: 1) determine if supplementation of Zilpaterol Hydrochloride (ZH) altered select organ weights, histology and cardiac anatomical features at harvest and 2) determine if administration of a corticotropin-releasing hormone (CRH) and vasopressin (VP) challenge followi...
The chemical composition of atmospheric precipitation from selected stations in Michigan
Curtis J. Richardson; George E. Merva
1976-01-01
The pH and amount of rainfall from over 60 selected stations throughout northern and lower Michigan was determined from September 1972 to December 1974. Precipitation pH was determined for each station by calibrated electrode meters. The seasonal weighted average and median pH from all stations in the study was 5.0 and 6.3, respectively. Daily readings from stations...
DATA QUALITY OBJECTIVES FOR SELECTING WASTE SAMPLES FOR THE BENCH STEAM REFORMER TEST
DOE Office of Scientific and Technical Information (OSTI.GOV)
BANNING DL
2010-08-03
This document describes the data quality objectives to select archived samples located at the 222-S Laboratory for Fluid Bed Steam Reformer testing. The type, quantity and quality of the data required to select the samples for Fluid Bed Steam Reformer testing are discussed. In order to maximize the efficiency and minimize the time to treat Hanford tank waste in the Waste Treatment and Immobilization Plant, additional treatment processes may be required. One of the potential treatment processes is the fluid bed steam reformer (FBSR). A determination of the adequacy of the FBSR process to treat Hanford tank waste is required.more » The initial step in determining the adequacy of the FBSR process is to select archived waste samples from the 222-S Laboratory that will be used to test the FBSR process. Analyses of the selected samples will be required to confirm the samples meet the testing criteria.« less
DOT National Transportation Integrated Search
1978-09-01
A five-test selection battery was given to select Air Traffic Controllers. Data were collected on two new tests being considered for incorporation into the battery. To determine the utility of the old and new tests, it is necessary to correlate the t...
Positive interference in lithium determinations from clot activator in collection container.
Sampson, M; Ruddel, M; Albright, S; Elin, R J
1997-04-01
We describe positive interference with the ion-selective electrode determination of lithium (Lytening 2Z analyzer; Dade) when blood is collected in a 10-mL plain red-top plastic Vacutainer Plus Tube (Becton Dickinson) containing a silica clot activator and silicone surfactant (prod. no. 36-7820). We evaluated both the original tube (blue-labeled) and a new tube formulated to contain less silicone surfactant (striped-labeled). We determined that the interference is from either the silica clot activator or the silicone surfactant used to fix the silica to the tube and is inversely related to the volume of blood in the tube. Long-term intermittent exposure of the Li ion-selective electrode to the silica clot activator or surfactant results in decreased Li values--in terms of both the positive interference by the silica clot activator or surfactant and the actual Li determinations. Moreover, this long-term interference with the Li ion-selective electrode for patient's specimens is undetected by the Dade control material (QCLytes).
Selective Mutism Questionnaire: Measurement Structure and Validity
ERIC Educational Resources Information Center
Letamendi, Andrea M.; Chavira, Denise A.; Hitchcock, Carla A.; Roesch, Scott C.; Shipon-Blum, Elisa; Stein, Murray B.
2008-01-01
The psychometric properties of the Selective Mutism Questionnaire (SMQ) are evaluated using a clinical sample of children with selective mutism (SM). The study shows that SMQ is useful in determining the severity of a child's nonspeaking behaviors, the scope of these behaviors and necessary follow up assessment.
Code of Federal Regulations, 2010 CFR
2010-04-01
...-DETERMINATION AND EDUCATION ACT Selection of Additional Tribes for Participation in Tribal Self-Governance...). A Tribe may be selected to negotiate an AFA under section 403(c) at the same time that it negotiates...
SH2 Domains Recognize Contextual Peptide Sequence Information to Determine Selectivity*
Liu, Bernard A.; Jablonowski, Karl; Shah, Eshana E.; Engelmann, Brett W.; Jones, Richard B.; Nash, Piers D.
2010-01-01
Selective ligand recognition by modular protein interaction domains is a primary determinant of specificity in signaling pathways. Src homology 2 (SH2) domains fulfill this capacity immediately downstream of tyrosine kinases, acting to recruit their host polypeptides to ligand proteins harboring phosphorylated tyrosine residues. The degree to which SH2 domains are selective and the mechanisms underlying selectivity are fundamental to understanding phosphotyrosine signaling networks. An examination of interactions between 50 SH2 domains and a set of 192 phosphotyrosine peptides corresponding to physiological motifs within FGF, insulin, and IGF-1 receptor pathways indicates that individual SH2 domains have distinct recognition properties and exhibit a remarkable degree of selectivity beyond that predicted by previously described binding motifs. The underlying basis for such selectivity is the ability of SH2 domains to recognize both permissive amino acid residues that enhance binding and non-permissive amino acid residues that oppose binding in the vicinity of the essential phosphotyrosine. Neighboring positions affect one another so local sequence context matters to SH2 domains. This complex linguistics allows SH2 domains to distinguish subtle differences in peptide ligands. This newly appreciated contextual dependence substantially increases the accessible information content embedded in the peptide ligands that can be effectively integrated to determine binding. This concept may serve more broadly as a paradigm for subtle recognition of physiological ligands by protein interaction domains. PMID:20627867
Genomic analysis reveals major determinants of cis-regulatory variation in Capsella grandiflora
Steige, Kim A.; Laenen, Benjamin; Reimegård, Johan; Slotte, Tanja
2017-01-01
Understanding the causes of cis-regulatory variation is a long-standing aim in evolutionary biology. Although cis-regulatory variation has long been considered important for adaptation, we still have a limited understanding of the selective importance and genomic determinants of standing cis-regulatory variation. To address these questions, we studied the prevalence, genomic determinants, and selective forces shaping cis-regulatory variation in the outcrossing plant Capsella grandiflora. We first identified a set of 1,010 genes with common cis-regulatory variation using analyses of allele-specific expression (ASE). Population genomic analyses of whole-genome sequences from 32 individuals showed that genes with common cis-regulatory variation (i) are under weaker purifying selection and (ii) undergo less frequent positive selection than other genes. We further identified genomic determinants of cis-regulatory variation. Gene body methylation (gbM) was a major factor constraining cis-regulatory variation, whereas presence of nearby transposable elements (TEs) and tissue specificity of expression increased the odds of ASE. Our results suggest that most common cis-regulatory variation in C. grandiflora is under weak purifying selection, and that gene-specific functional constraints are more important for the maintenance of cis-regulatory variation than genome-scale variation in the intensity of selection. Our results agree with previous findings that suggest TE silencing affects nearby gene expression, and provide evidence for a link between gbM and cis-regulatory constraint, possibly reflecting greater dosage sensitivity of body-methylated genes. Given the extensive conservation of gbM in flowering plants, this suggests that gbM could be an important predictor of cis-regulatory variation in a wide range of plant species. PMID:28096395
Personnel Selection Influences on Remotely Piloted Aircraft Human-System Integration.
Carretta, Thomas R; King, Raymond E
2015-08-01
Human-system integration (HSI) is a complex process used to design and develop systems that integrate human capabilities and limitations in an effective and affordable manner. Effective HSI incorporates several domains, including manpower, personnel and training, human factors, environment, safety, occupational health, habitability, survivability, logistics, intelligence, mobility, and command and control. To achieve effective HSI, the relationships among these domains must be considered. Although this integrated approach is well documented, there are many instances where it is not followed. Human factors engineers typically focus on system design with little attention to the skills, abilities, and other characteristics needed by human operators. When problems with fielded systems occur, additional training of personnel is developed and conducted. Personnel selection is seldom considered during the HSI process. Complex systems such as aviation require careful selection of the individuals who will interact with the system. Personnel selection is a two-stage process involving select-in and select-out procedures. Select-in procedures determine which candidates have the aptitude to profit from training and represent the best investment. Select-out procedures focus on medical qualification and determine who should not enter training for medical reasons. The current paper discusses the role of personnel selection in the HSI process in the context of remotely piloted aircraft systems.
Bunz, Svenja-Catharina; Neusüß, Christian
2013-01-01
Metabolite identification and metabolite profiling are of major importance in the pharmaceutical and clinical context. However, anions of biological relevance such as sulfates, sulfonates, and phosphates are rarely included in common techniques for metabolite studies. In this protocol, we demonstrate a unique method to selectively determine these anions. The method comprises a capillary electrophoresis separation using an acidic background electrolyte (pH ≤ 2) and anodic detection by mass spectrometry via negative electrospray ionization. In this way, only anions of strong acids like sulfates are determined. The selectivity for sulfur-containing species is proved based on the specific isotopic ratios. In conjunction with the accurate mass from the time-of-flight mass spectrometer, the presented method is well suited for clinical and pharmaceutical applications to identify possible metabolites and to quantify known metabolites.
A space efficient flexible pivot selection approach to evaluate determinant and inverse of a matrix.
Jafree, Hafsa Athar; Imtiaz, Muhammad; Inayatullah, Syed; Khan, Fozia Hanif; Nizami, Tajuddin
2014-01-01
This paper presents new simple approaches for evaluating determinant and inverse of a matrix. The choice of pivot selection has been kept arbitrary thus they reduce the error while solving an ill conditioned system. Computation of determinant of a matrix has been made more efficient by saving unnecessary data storage and also by reducing the order of the matrix at each iteration, while dictionary notation [1] has been incorporated for computing the matrix inverse thereby saving unnecessary calculations. These algorithms are highly class room oriented, easy to use and implemented by students. By taking the advantage of flexibility in pivot selection, one may easily avoid development of the fractions by most. Unlike the matrix inversion method [2] and [3], the presented algorithms obviate the use of permutations and inverse permutations.
NASA Technical Reports Server (NTRS)
Schwab, Andrew J. (Inventor); Aylor, James (Inventor); Hitchcock, Charles Young (Inventor); Wulf, William A. (Inventor); McKee, Sally A. (Inventor); Moyer, Stephen A. (Inventor); Klenke, Robert (Inventor)
2000-01-01
A data processing system is disclosed which comprises a data processor and memory control device for controlling the access of information from the memory. The memory control device includes temporary storage and decision ability for determining what order to execute the memory accesses. The compiler detects the requirements of the data processor and selects the data to stream to the memory control device which determines a memory access order. The order in which to access said information is selected based on the location of information stored in the memory. The information is repeatedly accessed from memory and stored in the temporary storage until all streamed information is accessed. The information is stored until required by the data processor. The selection of the order in which to access information maximizes bandwidth and decreases the retrieval time.
NASA Astrophysics Data System (ADS)
Sun, Tao; Li, Yang; Niu, Qingfen; Li, Tianduo; Liu, Yan
2018-04-01
A new simple and efficient fluorescent sensor L based on 1,8-diaminonaphthalene Schiff-base for highly sensitive and selective determination of Cu2+ in drink and water has been developed. This Cu2+-selective detection over other tested metal ions displayed an obvious color change from blue to colorless easily detected by naked eye. The detection limit is determined to be as low as 13.2 nM and the response time is very fast within 30 s. The 1:1 binding mechanism was well confirmed by fluorescence measurements, IR analysis and DFT calculations. Importantly, this sensor L was employed for quick detection of Cu2+ in drink and environmental water samples with satisfactory results, providing a simple, rapid, reliable and feasible Cu2+-sensing method.
A bootstrap based Neyman-Pearson test for identifying variable importance.
Ditzler, Gregory; Polikar, Robi; Rosen, Gail
2015-04-01
Selection of most informative features that leads to a small loss on future data are arguably one of the most important steps in classification, data analysis and model selection. Several feature selection (FS) algorithms are available; however, due to noise present in any data set, FS algorithms are typically accompanied by an appropriate cross-validation scheme. In this brief, we propose a statistical hypothesis test derived from the Neyman-Pearson lemma for determining if a feature is statistically relevant. The proposed approach can be applied as a wrapper to any FS algorithm, regardless of the FS criteria used by that algorithm, to determine whether a feature belongs in the relevant set. Perhaps more importantly, this procedure efficiently determines the number of relevant features given an initial starting point. We provide freely available software implementations of the proposed methodology.
Mohamed, Gehad G; El-Shahat, M F; Al-Sabagh, A M; Migahed, M A; Ali, Tamer Awad
2011-04-07
A screen-printed electrode (SPE) was fabricated for the determination of 1-(ethoxycarbonyl)pentadecyltrimethylammonium bromide (Septonex) based on the use of Septonex-tetraphenylborate as the electroactive substance, and o-nitrophenyloctylether (o-NPOE) as the plasticizing agent. The electrode passes a near-Nernstian cationic slope of 59.33 ± 0.85 mV from activity between pH values of 2 to 9 with a lower detection limit of 9×10(-7) M and response time of about 5 s and exhibits an adequate shelf-life of 6 months. The method was applied for the determination of Septonex in pharmaceutical preparations. A percentage recovery of 99.88% was obtained with RSD=1.24%. The electrode was successfully applied in the determination of Septonex in laboratory-prepared samples by direct potentiometric, calibration curve and standard addition methods. Potentiometric titration of Septonex with sodium tetraphenylborate and phosphotungstic acid as a titrant was monitored with the modified screen-printed electrode as an end-point indicator electrode. Selectivity coefficients for Septonex relative to a number of potential interfering substances were determined. The sensor was highly selective for Septonex over a large number of compounds. Selectivity coefficient data for some common ions show negligible interference; however, cetyltrimethylammonium bromide and iodide ions interfere significantly. The analytical usefulness of the proposed electrode was evaluated by its application in the determination of Septonex in laboratory-prepared pharmaceutical samples with satisfactory results. The results obtained with the fabricated sensor are comparable with those obtained by the British Pharmacopeia method. © The Royal Society of Chemistry 2011
A probabilistic method for testing and estimating selection differences between populations
He, Yungang; Wang, Minxian; Huang, Xin; Li, Ran; Xu, Hongyang; Xu, Shuhua; Jin, Li
2015-01-01
Human populations around the world encounter various environmental challenges and, consequently, develop genetic adaptations to different selection forces. Identifying the differences in natural selection between populations is critical for understanding the roles of specific genetic variants in evolutionary adaptation. Although numerous methods have been developed to detect genetic loci under recent directional selection, a probabilistic solution for testing and quantifying selection differences between populations is lacking. Here we report the development of a probabilistic method for testing and estimating selection differences between populations. By use of a probabilistic model of genetic drift and selection, we showed that logarithm odds ratios of allele frequencies provide estimates of the differences in selection coefficients between populations. The estimates approximate a normal distribution, and variance can be estimated using genome-wide variants. This allows us to quantify differences in selection coefficients and to determine the confidence intervals of the estimate. Our work also revealed the link between genetic association testing and hypothesis testing of selection differences. It therefore supplies a solution for hypothesis testing of selection differences. This method was applied to a genome-wide data analysis of Han and Tibetan populations. The results confirmed that both the EPAS1 and EGLN1 genes are under statistically different selection in Han and Tibetan populations. We further estimated differences in the selection coefficients for genetic variants involved in melanin formation and determined their confidence intervals between continental population groups. Application of the method to empirical data demonstrated the outstanding capability of this novel approach for testing and quantifying differences in natural selection. PMID:26463656
Distractor Inhibition: Principles of Operation during Selective Attention
ERIC Educational Resources Information Center
Wyatt, Natalie; Machado, Liana
2013-01-01
Research suggests that although target amplification acts as the main determinant of the efficacy of selective attention, distractor inhibition contributes under some circumstances. Here we aimed to gain insight into the operating principles that regulate the use of distractor inhibition during selective attention. The results suggest that, in…
24 CFR 983.251 - How participants are selected.
Code of Federal Regulations, 2010 CFR
2010-04-01
.... (a) Who may receive PBV assistance? (1) The PHA may select families who are participants in the PHA's tenant-based voucher program and families who have applied for admission to the voucher program. (2... PHA may only select families determined eligible for admission at commencement of PBV assistance. (3...
How To Select and Plant a Tree.
ERIC Educational Resources Information Center
Fazio, James R., Ed.
1991-01-01
This bulletin furnishes information about selecting and planting trees. The tree selection process includes being aware of the physical characteristics of bare root seedlings, containerized seedlings, balled and burlapped, or potted trees and determining the proper size and root ball proportions. The section on tree planting discusses how to: (1)…
Academic Clustering and Major Selection of Intercollegiate Student-Athletes
ERIC Educational Resources Information Center
Schneider, Ray G.; Ross, Sally R.; Fisher, Morgan
2010-01-01
Although journalists and reporters have written about academic clustering among college student-athletes, there has been a dearth of scholarly analysis devoted to the subject. This study explored football players' academic major selections to determine if academic clustering actually existed. The seasons 1996, 2001, and 2006 were selected for…
5 CFR 330.608 - Application and selection.
Code of Federal Regulations, 2010 CFR
2010-01-01
... identifying the employee as being in a surplus organization or occupation. (b) Selection. An agency may decide... vacancies. (d) If two or more eligible employees apply for a vacancy and are determined to be well-qualified... well-qualified, the agency may select another agency employee without regard to this subpart. ...
Luo, Zhenhua; Liu, Bingwan; Liu, Songtao; Jiang, Zhigang; Halbrook, Richard S
2014-01-01
Human and livestock related disturbances of habitat selection by ungulates are topics of global concern, as they have profound impacts on ungulate survival, population density, fitness, and management; however, differences in ungulate habitat use under different human and livestock densities are not fully understood. Mongolian gazelle (Procapra gutturosa), an endemic ungulate species on the Asia-European steppe, faces varying intensities of human and livestock disturbances in the area around Dalai Lake, China. To investigate how habitat selection strategies vary as disturbance intensity changes, we randomly set 20 transects containing 1486 plots, on which we conducted repeated surveys of 21 ecological factors during the winters in the period of 2005-2008. We aimed to: 1) determine the critical factors underlying habitat selection of the gazelles; 2) determine the gazelles' habitat preferences in this area; 3) determine how habitat selection varies with disturbance intensity and explore the primary underlying mechanism. We used binary-logistic regressions and information theoretic approaches to build best-fit habitat selection models, and calculated resource selection functions. Sixty-six herds, 522 individuals, and 499 tracks were recorded. Our results indicate that snow depth and aboveground biomass are the main factors affecting habitat selection by Mongolian gazelle throughout the district in winter. Thin snow cover and abundant aboveground biomass are preferred. Avoiding disturbance was the primary factor accounting for habitat selection in low disturbance areas, although with increasing human or live-stock-related disturbance, gazelle maintained a reduced distance to the source of the disturbance. Presumably owing to that shift, movement costs were more important as disturbance increased. In addition, Mongolian gazelle selected habitats based on topographical features promoting greater visibility where disturbance was lower. We suggest several management implications of our findings for this ungulate species will contribute to the effective conservation of Mongolian gazelle in the Dalai Lake area.
34 CFR 668.37 - Selective Service registration.
Code of Federal Regulations, 2010 CFR
2010-07-01
... Secretary processes a male student's FAFSA, the Secretary determines whether the student is registered with... Selective Service Act. The designated official shall not consider challenges based on constitutional or...
Biological Ion Exchanger Resins
Damadian, Raymond; Goldsmith, Michael; Zaner, K. S.
1971-01-01
Biological selectivity is shown to vary with medium osmotic strength and temperature. Selectivity reversals occur at 4°C and at an external osmolality of 0.800 indicating that intracellular hydration and endosolvent (intracellular water) structure are important determinants in selectivity. Magnetic resonance measurements of line width by steady-state nuclear magnetic resonance (NMR) indicate a difference in the intracellular water signal of 16 Hz between the K form and Na form of Escherichia coli, providing additional evidence that changes in the ionic composition of cells are accompanied by changes in endosolvent structure. The changes were found to be consistent with the thermodynamic and magnetic resonance properties of aqueous electrolyte solutions. Calculation of the dependence of ion-pairing forces on medium dielectric reinforces the role of endosolvent structure in determining ion exchange selectivity. PMID:4943653
NASA Technical Reports Server (NTRS)
1977-01-01
Initial screening tests and the results obtained in developing procedures to determine Al, Cu, Fe, and Pb in glycol formulations are described. Atomic absorption completion was selected for Cu, Fe and Pb, and after comparison with emission spectroscopy, was selected for Al also. Before completion, carbon, iron, and lead are extracted with diethyl dithio carbamate (DDC) into methyl isobutyl ketone (MIBK). Aluminum was also extracted into MIBK using 8-hydroxyquinoline as a chelating agent. As little as 0.02 mg/l carbon and 0.06 mg/l lead or iron may be determined in glycol formulations. As little as 0.3 mg/l aluminum may be determined.
Support requirements for remote sensor systems on unmanned planetary missions, phase 3
NASA Technical Reports Server (NTRS)
1971-01-01
The results of a study to determine the support requirements for remote sensor systems on unmanned planetary flyby and orbiter missions are presented. Sensors and experiment groupings for selected missions are also established. Computer programs were developed to relate measurement requirements to support requirements. Support requirements were determined for sensors capable of performing required measurements at various points along the trajectories of specific selected missions.
Development of Gamma-Emitting Receptor Binding Radiopharmace
DOE Office of Scientific and Technical Information (OSTI.GOV)
Reba, Richard
2003-02-20
The long-term objective is to develop blood-brain barrier (BBB) permeable m2-selective (relative to m1, m3, and m4) receptor-binding radiotracers and utilize these radiotracers for quantifying receptor concentrations obtained from PET or SPECT images of human brain. In initial studies, we concluded that the lipophilicity and high affinity prevented (R,S)-I-QNB from reaching a flow-independent and receptor-dependent state in a reasonable time. Thus, it was clear that (R,S)-I-QNB should be modified. Therefore, during the last portion of this funded research, we proposed that more polar heterocycles should help accomplish that. Since reports of others concluded that radiobromination and radiofluorination of the unactivatedmore » phenyl ring is not feasible (Newkome et al,,1982), we, therefore, explored during this grant period a series of analogues of (R)-QNB in which one or both of the six-membered phenyl rings is replaced by a five-membered thienyl (Boulay et al., 1995), or furyl ring. The chemistry specific aims were to synthesize novel compounds designed to be m2-selective mAChR ligands capable of penetrating into the CNS, and develop methods for efficient radiolabeling of promising m2-selective muscarinic ligands. The pharmacology specific aims were to determine the affinity and subtype-selectivity of the novel compounds using competition binding studies with membranes from cells that express each of the five muscarinic receptor subtypes, to determine the ability of the promising non-radioactive compounds and radiolabeled novel compounds to cross the BBB, to determine the biodistribution, in-vivo pharmacokinetics, and in-vitm kinetics of promising m2-selective radioligands and to determine the distribution of receptors for the novel m2-selective radioligands using quantitative autoradiography of rat brain, and compare this distribution to the distribution of known m2-selective compounds.« less
Oskoei, Yones Mosaei; Fattahi, Hassan; Hassanzadeh, Javad; Azar, Ali Mousavi
2016-01-01
A fluorescence resonance energy transfer (FRET) system between carbon dots (C-dots) and amine-capped gold nanoparticles (AuNPs) was developed for the selective determination of 2,4,6-trinitrotoluene (TNT). C-dots have an intrinsic florescence emission depending on their exciting wavelength. In the presence of AuNPs, C-dots adsorb on the Au surfaces, and NPs treat as energy acceptor, which can receive light emitted by C-dots, leading to decrease the fluorescence intensity of C-dots. Furthermore, it is observed that nitroaromatic compounds, especially TNT, could restore this fluorescence due to selective interaction with AuNPs via amine groups, and so releasing the C-dots. Based on this effect, a sensitive and selective fluorescence turn-on probe was designed for the determination of TNT. Some important factors including AuNPs and C-dot concentrations and media pH, which would affect the efficiency of the probe, were optimized. Under the optimum experimental conditions, good linear relationships in the range of 7 - 250 nmol L(-1) TNT with the detection limit of 2.2 nmol L(-1) were obtained. The proposed method was satisfactorily applied to the determination of TNT in the environmental water samples. Compared with previous reports, the developed method has relatively high sensitivity, short analysis time, low cost and ease of operation.
Longevity enhances selection of environmental sex determination.
Bull, J J; Bulmer, M G
1989-12-01
Environmental sex determination (ESD) is a mechanism in which an individual develops as male or female largely in response to some environmental effect experienced early in life. Its forms range from sex determination by egg incubation temperature in reptiles to sex determination of photoperiod in amphipods. Previous theoretical work as suggested that ESD is favored by natural selection if the fitness consequences of the early environmental experience differ for males and females, so that an individual benefits by being male under some conditions and female under others. A drawback of ESD is that it enables climatic changes to influence the population sex ratio, and such fluctuations select against ESD. This study employed numerical analyses to investigate the balance between these two opposing forces. The negative impact of climatic fluctuations appears to depend greatly on species longevity: substantial between-year fluctuations are of little consequence in selecting against ESD in long-lived species because annual sex ratio fluctuations tend to cancel and thus alter the total population sex ratio only slightly. Thus, if a species is sufficiently long-lived, extreme ESD can be maintained despite only a weak advantage. This result offers one explanation for the failure to demonstrate an advantage for the extreme forms of ESD observed in reptiles.
Pontremoli, Chiara; Forni, Diego; Cagliani, Rachele; Pozzoli, Uberto; Riva, Stefania; Bravo, Ignacio G; Clerici, Mario; Sironi, Manuela
2017-10-01
The Old World (OW) arenavirus complex includes several species of rodent-borne viruses, some of which (i.e., Lassa virus, LASV and Lymphocytic choriomeningitis virus, LCMV) cause human diseases. Most LCMV and LASV infections are caused by rodent-to-human transmissions. Thus, viral evolution is largely determined by events that occur in the wildlife reservoirs. We used a set of human- and rodent-derived viral sequences to investigate the evolutionary history underlying OW arenavirus speciation, as well as the more recent selective events that accompanied LASV spread in West Africa. We show that the viral RNA polymerase (L protein) was a major positive selection target in OW arenaviruses and during LASV out-of-Nigeria migration. No evidence of selection was observed for the glycoprotein, whereas positive selection acted on the nucleoprotein (NP) during LCMV speciation. Positively selected sites in L and NP are surrounded by highly conserved residues, and the bulk of the viral genome evolves under purifying selection. Several positively selected sites are likely to modulate viral replication/transcription. In both L and NP, structural features (solvent exposed surface area) are important determinants of site-wise evolutionary rate variation. By incorporating several rodent-derived sequences, we also performed an analysis of OW arenavirus codon adaptation to the human host. Results do not support a previously hypothesized role of codon adaptation in disease severity for non-Nigerian strains. In conclusion, L and NP represent the major selection targets and possible determinants of disease presentation; these results suggest that field surveys and experimental studies should primarily focus on these proteins. © 2017 John Wiley & Sons Ltd.
2016-06-15
selection strategy is key to minimizing risk and ensuring best value for all stakeholders. On the basis of thorough market research , acquisition...administrative lead-time, Contractor Performance Assessment Reporting System ratings, and earned value management assessments) and source selection strategy ...Postgraduate School A. PURPOSE This research analyzes LPTA and tradeoff source selection strategies and contract outcomes to determine if a relationship
Song, Yingcai; Zhang, Bing; Guo, Fei; Yang, Maojun; Li, Yang; Liu, Zhi-Qiang
2017-01-01
The mechanosensitive channel of small conductance (MscS) is a bacterial membrane pore that senses membrane tension and protects cells from lysis by releasing osmolytes. MscS is a homoheptameric channel with a cytoplasmic domain with seven portals and a β-barrel opening to the cytoplasm. TtMscS, an MscS channel from Thermoanaerobacter tengcongensis, is an anion-selective channel. A previous study from our laboratory has defined the crucial role of β-barrel in the anion selectivity of TtMscS (Zhang et al., 2012). However, the mechanistic details by which the β-barrel determines anion selectivity remain unclear. Here, using mutagenesis and patch-clamp recordings, we investigated the function and structural correlations between β-barrels and the anion selectivity of TtMscS at the atomic level. Our results indicated that mutation of V274, a residue at the center of the inner wall of the β-barrel in TtMscS, caused the anion selectivity of TtMscS reverse to cation selectivity. Moreover, the electrostatic potential (T272) and physical size (L276) of residues in the inner wall of β-barrel also determine the anion selectivity of TtMscS. In summary, the present study confirmed that the β-barrel region of TtMscS acts as a “selective filter” that renders TtMscS anion selectivity. PMID:29118717
Patterns of Positive Selection of the Myogenic Regulatory Factor Gene Family in Vertebrates
Zhao, Xiao; Yu, Qi; Huang, Ling; Liu, Qing-Xin
2014-01-01
The functional divergence of transcriptional factors is critical in the evolution of transcriptional regulation. However, the mechanism of functional divergence among these factors remains unclear. Here, we performed an evolutionary analysis for positive selection in members of the myogenic regulatory factor (MRF) gene family of vertebrates. We selected 153 complete vertebrate MRF nucleotide sequences from our analyses, which revealed substantial evidence of positive selection. Here, we show that sites under positive selection were more frequently detected and identified from the genes encoding the myogenic differentiation factors (MyoG and Myf6) than the genes encoding myogenic determination factors (Myf5 and MyoD). Additionally, the functional divergence within the myogenic determination factors or differentiation factors was also under positive selection pressure. The positive selection sites were more frequently detected from MyoG and MyoD than Myf6 and Myf5, respectively. Amino acid residues under positive selection were identified mainly in their transcription activation domains and on the surface of protein three-dimensional structures. These data suggest that the functional gain and divergence of myogenic regulatory factors were driven by distinct positive selection of their transcription activation domains, whereas the function of the DNA binding domains was conserved in evolution. Our study evaluated the mechanism of functional divergence of the transcriptional regulation factors within a family, whereby the functions of their transcription activation domains diverged under positive selection during evolution. PMID:24651579
Male-male competition, female mate choice and their interaction: determining total sexual selection.
Hunt, John; Breuker, Casper J; Sadowski, Jennifer A; Moore, Allen J
2009-01-01
Empirical studies of sexual selection typically focus on one of the two mechanisms of sexual selection without integrating these into a description of total sexual selection, or study total sexual selection without quantifying the contributions of all of the mechanisms of sexual selection. However, this can provide an incomplete or misleading view of how sexually selected traits evolve if the mechanisms of sexual selection are opposing or differ in form. Here, we take a two-fold approach to advocate a direction for future studies of sexual selection. We first show how a quantitative partitioning and examination of sexual selection mechanisms can inform by identifying illustrative studies that describe both male-male competition and female mate choice acting on the same trait. In our sample, the most common trait where this occurred was body size, and selection was typically linear. We found that male-male competition and female mate choice can be reinforcing or opposing, although the former is most common in the literature. The mechanisms of sexual selection can occur simultaneously or sequentially, and we found they were more likely to be opposing when the mechanisms operated sequentially. The degree and timing that these mechanisms interact have important implications for the operation of sexual selection and needs to be considered in designing studies. Our examples highlight where empirical data are needed. We especially lack standardized measures of the form and strength of selection imposed by each mechanism of sexual selection and how they combine to determine total sexual selection. Secondly, using quantitative genetic principles, we outline how the selection imposed by individual mechanisms can be measured and combined to estimate the total strength and form of sexual selection. We discuss the evolutionary consequences of combining the mechanisms of sexual selection and interpreting total sexual selection. We suggest how this approach may result in empirical progress in the field of sexual selection.
NASA Technical Reports Server (NTRS)
Simon, F. F.
1975-01-01
The use of a solar simulator for performance determination permits collector testing under standard conditions of wind, ambient temperature, flow rate and sun. The performance results determined with the simulator have been found to be in good agreement with outdoor performance results. The measured thermal efficiency and evaluation of 23 collectors are reported which differ according to absorber material (copper, aluminum, steel), absorber coating (nonselective black paint, selective copper oxide, selective black nickel, selective black chrome), type of glazing material (glass, Tedlar, Lexan, antireflection glass), the use of honeycomb material and the use of vacuum to prevent thermal convection losses. The collectors were given performance rankings based on noon-hour solar conditions and all-day solar conditions. The determination with the simulator of an all-day collector performance was made possible by tests at different incident angles. The solar performance rankings were made based on whether the collector is to be used for pool heating, hot water, absorption air conditioning, heating, or for a solar Rankine machine.
Measuring individual work performance: identifying and selecting indicators.
Koopmans, Linda; Bernaards, Claire M; Hildebrandt, Vincent H; de Vet, Henrica C W; van der Beek, Allard J
2014-01-01
Theoretically, individual work performance (IWP) can be divided into four dimensions: task performance, contextual performance, adaptive performance, and counterproductive work behavior. However, there is no consensus on the indicators used to measure these dimensions. This study was designed to (1) identify indicators for each dimension, (2) select the most relevant indicators, and (3) determine the relative weight of each dimension in ratings of work performance. IWP indicators were identified from multiple research disciplines, via literature, existing questionnaires, and expert interviews. Subsequently, experts selected the most relevant indicators per dimension and scored the relative weight of each dimension in ratings of IWP. In total, 128 unique indicators were identified. Twenty-three of these indicators were selected by experts as most relevant for measuring IWP. Task performance determined 36% of the work performance rating, while the other three dimensions respectively determined 22%, 20% and 21% of the rating. Notable consensus was found on relevant indicators of IWP, reducing the number from 128 to 23 relevant indicators. This provides an important step towards the development of a standardized, generic and short measurement instrument for assessing IWP.
Yuan, Xiaoqiu; Yin, Ping; Hao, Qi; Yan, Chuangye; Wang, Jiawei; Yan, Nieng
2010-01-01
Abscisic acid (ABA) is one of the most important phytohormones in plant. PYL proteins were identified to be ABA receptors in Arabidopsis thaliana. Despite the remarkably high degree of sequence similarity, PYL1 and PYL2 exhibit distinct responses toward pyrabactin, an ABA agonist. PYL1 inhibits protein phosphatase type 2C upon binding of pyrabactin. In contrast, PYL2 appears relatively insensitive to this compound. The crystal structure of pyrabactin-bound PYL1 revealed that most of the PYL1 residues involved in pyrabactin binding are conserved, hence failing to explain the selectivity of pyrabactin for PYL1 over PYL2. To understand the molecular basis of pyrabactin selectivity, we determined the crystal structure of PYL2 in complex with pyrabactin at 1.64 Å resolution. Structural comparison and biochemical analyses demonstrated that one single amino acid alteration between a corresponding valine and isoleucine determines the distinct pyrabactin selectivity by PYL1 and PYL2. These characterizations provide an important clue to dissecting the redundancy of PYL proteins. PMID:20630864
Study to determine cloud motion from meteorological satellite data
NASA Technical Reports Server (NTRS)
Clark, B. B.
1972-01-01
Processing techniques were tested for deducing cloud motion vectors from overlapped portions of pairs of pictures made from meteorological satellites. This was accomplished by programming and testing techniques for estimating pattern motion by means of cross correlation analysis with emphasis placed upon identifying and reducing errors resulting from various factors. Techniques were then selected and incorporated into a cloud motion determination program which included a routine which would select and prepare sample array pairs from the preprocessed test data. The program was then subjected to limited testing with data samples selected from the Nimbus 4 THIR data provided by the 11.5 micron channel.
A proposed configurable approach for recommendation systems via data mining techniques
NASA Astrophysics Data System (ADS)
Khedr, Ayman E.; Idrees, Amira M.; Hegazy, Abd El-Fatah; El-Shewy, Samir
2018-02-01
This study presents a configurable approach for recommendations which determines the suitable recommendation method for each field based on the characteristics of its data, the method includes determining the suitable technique for selecting a representative sample of the provided data. Then selecting the suitable feature weighting measure to provide a correct weight for each feature based on its effect on the recommendations. Finally, selecting the suitable algorithm to provide the required recommendations. The proposed configurable approach could be applied on different domains. The experiments have revealed that the approach is able to provide recommendations with only 0.89 error rate percentage.
Mirmohseni, A; Abdollahi, H; Rostamizadeh, K
2007-02-28
Net analyte signal (NAS)-based method called HLA/GO was applied for the selectively determination of binary mixture of ethanol and water by quartz crystal nanobalance (QCN) sensor. A full factorial design was applied for the formation of calibration and prediction sets in the concentration ranges 5.5-22.2 microg mL(-1) for ethanol and 7.01-28.07 microg mL(-1) for water. An optimal time range was selected by procedure which was based on the calculation of the net analyte signal regression plot in any considered time window for each test sample. A moving window strategy was used for searching the region with maximum linearity of NAS regression plot (minimum error indicator) and minimum of PRESS value. On the base of obtained results, the differences on the adsorption profiles in the time range between 1 and 600 s were used to determine mixtures of both compounds by HLA/GO method. The calculation of the net analytical signal using HLA/GO method allows determination of several figures of merit like selectivity, sensitivity, analytical sensitivity and limit of detection, for each component. To check the ability of the proposed method in the selection of linear regions of adsorption profile, a test for detecting non-linear regions of adsorption profile data in the presence of methanol was also described. The results showed that the method was successfully applied for the determination of ethanol and water.
Moenickes, Sylvia; Höltge, Sibylla; Kreuzig, Robert; Richter, Otto
2011-12-01
Fate monitoring data on anaerobic transformation of the benzimidazole anthelmintics flubendazole (FLU) and fenbendazole (FEN) in liquid pig manure and aerobic transformation and sorption in soil and manured soil under laboratory conditions were used for corresponding fate modeling. Processes considered were reversible and irreversible sequestration, mineralization, and metabolization, from which a set of up to 50 different models, both nested and concurrent, was assembled. Five selection criteria served for model selection after parameter fitting: the coefficient of determination, modeling efficiency, a likelihood ratio test, an information criterion, and a determinability measure. From the set of models selected, processes were classified as essential or sufficient. This strategy to identify process dominance was corroborated through application to data from analogous experiments for sulfadiazine and a comparison with established fate models for this substance. For both, FLU and FEN, model selection performance was fine, including indication of weak data support where observed. For FLU reversible and irreversible sequestration in a nonextractable fraction was determined. In particular, both the extractable and the nonextractable fraction were equally sufficient sources for irreversible sequestration. For FEN generally reversible formation of the extractable sulfoxide metabolite and reversible sequestration of both the parent and the metabolite were dominant. Similar to FLU, irreversible sequestration in the nonextractable fraction was determined for which both the extractable or the nonextractable fraction were equally sufficient sources. Formation of the sulfone metabolite was determined as irreversible, originating from the first metabolite. Copyright © 2011 Elsevier B.V. All rights reserved.
ERIC Educational Resources Information Center
Hirsch, Jim
2001-01-01
Offers advice on selecting online vendors, such as determining quality, graduation credit, course articulation, delivery equipment, teacher support, handicap accessibility, pricing methods, and grading functions. Includes a selected list of vendors of online courses. (PKP)
Pleiotropic Models of Polygenic Variation, Stabilizing Selection, and Epistasis
Gavrilets, S.; de-Jong, G.
1993-01-01
We show that in polymorphic populations many polygenic traits pleiotropically related to fitness are expected to be under apparent ``stabilizing selection'' independently of the real selection acting on the population. This occurs, for example, if the genetic system is at a stable polymorphic equilibrium determined by selection and the nonadditive contributions of the loci to the trait value either are absent, or are random and independent of those to fitness. Stabilizing selection is also observed if the polygenic system is at an equilibrium determined by a balance between selection and mutation (or migration) when both additive and nonadditive contributions of the loci to the trait value are random and independent of those to fitness. We also compare different viability models that can maintain genetic variability at many loci with respect to their ability to account for the strong stabilizing selection on an additive trait. Let V(m) be the genetic variance supplied by mutation (or migration) each generation, V(g) be the genotypic variance maintained in the population, and n be the number of the loci influencing fitness. We demonstrate that in mutation (migration)-selection balance models the strength of apparent stabilizing selection is order V(m)/V(g). In the overdominant model and in the symmetric viability model the strength of apparent stabilizing selection is approximately 1/(2n) that of total selection on the whole phenotype. We show that a selection system that involves pairwise additive by additive epistasis in maintaining variability can lead to a lower genetic load and genetic variance in fitness (approximately 1/(2n) times) than an equivalent selection system that involves overdominance. We show that, in the epistatic model, the apparent stabilizing selection on an additive trait can be as strong as the total selection on the whole phenotype. PMID:8325491
Biomechanical and energetic determinants of technique selection in classical cross-country skiing.
Pellegrini, Barbara; Zoppirolli, Chiara; Bortolan, Lorenzo; Holmberg, Hans-Christer; Zamparo, Paola; Schena, Federico
2013-12-01
Classical cross-country skiing can be performed using three main techniques: diagonal stride (DS), double poling (DP), and double poling with kick (DK). Similar to other forms of human and animal gait, it is currently unclear whether technique selection occurs to minimize metabolic cost or to keep some mechanical factors below a given threshold. The aim of this study was to find the determinants of technique selection. Ten male athletes roller skied on a treadmill at different slopes (from 0° to 7° at 10km/h) and speeds (from 6 to 18km/h at 2°). The technique preferred by skiers was gathered for every proposed condition. Biomechanical parameters and metabolic cost were then measured for each condition and technique. Skiers preferred DP for skiing on the flat and they transitioned to DK and then to DS with increasing slope steepness, when increasing speed all skiers preferred DP. Data suggested that selections mainly occur to remain below a threshold of poling force. Second, critically low values of leg thrust time may limit the use of leg-based techniques at high speeds. A small role has been identified for the metabolic cost of locomotion, which determined the selection of DP for flat skiing. Copyright © 2013 Elsevier B.V. All rights reserved.
Evolutionary stasis in pollen morphogenesis due to natural selection.
Matamoro-Vidal, Alexis; Prieu, Charlotte; Furness, Carol A; Albert, Béatrice; Gouyon, Pierre-Henri
2016-01-01
The contribution of developmental constraints and selective forces to the determination of evolutionary patterns is an important and unsolved question. We test whether the long-term evolutionary stasis observed for pollen morphogenesis (microsporogenesis) in eudicots is due to developmental constraints or to selection on a morphological trait shaped by microsporogenesis: the equatorial aperture pattern. Most eudicots have three equatorial apertures but several taxa have independently lost the equatorial pattern and have microsporogenesis decoupled from aperture pattern determination. If selection on the equatorial pattern limits variation, we expect to see increased variation in microsporogenesis in the nonequatorial clades. Variation of microsporogenesis was studied using phylogenetic comparative analyses in 83 species dispersed throughout eudicots including species with and without equatorial apertures. The species that have lost the equatorial pattern have highly variable microsporogenesis at the intra-individual and inter-specific levels regardless of their pollen morphology, whereas microsporogenesis remains stable in species with the equatorial pattern. The observed burst of variation upon loss of equatorial apertures shows that there are no strong developmental constraints precluding variation in microsporogenesis, and that the stasis is likely to be due principally to selective pressure acting on pollen morphogenesis because of its implication in the determination of the equatorial aperture pattern. © 2015 The Authors. New Phytologist © 2015 New Phytologist Trust.
Bernevic, Bogdan; El-Khatib, Ahmed H; Jakubowski, Norbert; Weller, Michael G
2018-04-02
The human copper-protein ceruloplasmin (Cp) is the major copper-containing protein in the human body. The accurate determination of Cp is mandatory for the reliable diagnosis of several diseases. However, the analysis of Cp has proven to be difficult. The aim of our work was a proof of concept for the determination of a metalloprotein-based on online immunocapture ICP-MS. The immuno-affinity step is responsible for the enrichment and isolation of the analyte from serum, whereas the compound-independent quantitation with ICP-MS delivers the sensitivity, precision, and large dynamic range. Off-line ELISA (enzyme-linked immunosorbent assay) was used in parallel to confirm the elution profile of the analyte with a structure-selective method. The total protein elution was observed with the 32 S mass trace. The ICP-MS signals were normalized on a 59 Co signal. The human copper-protein Cp could be selectively determined. This was shown with pure Cp and with a sample of human serum. The good correlation with off-line ELISA shows that Cp could be captured and eluted selectively from the anti-Cp affinity column and subsequently determined by the copper signal of ICP-MS.
Code of Federal Regulations, 2010 CFR
2010-07-01
... EMISSIONS FROM NEW AND IN-USE NONROAD COMPRESSION-IGNITION ENGINES Selective Enforcement Auditing § 89.503... Selective Enforcement Auditing (SEA) test orders than an annual limit determined to be the larger of the...
CADDIS Volume 4. Data Analysis: Selecting an Analysis Approach
An approach for selecting statistical analyses to inform causal analysis. Describes methods for determining whether test site conditions differ from reference expectations. Describes an approach for estimating stressor-response relationships.
Khan, Sadia; Beattie, Tara K; Knapp, Charles W
2017-03-01
The use of antimicrobial compounds is indispensable in many industries, especially drinking water production, to eradicate microorganisms. However, bacterial growth is not unusual in the presence of disinfectant concentrations that would be typically lethal, as bacterial populations can develop resistance. The common metric of population resistance has been based on the Minimum Inhibitory Concentration (MIC), which is based on bacteria lethality. However, sub-lethal concentrations may also select for resistant bacteria due to the differences in bacterial growth rates. This study determined the Minimal Selective Concentrations (MSCs) of bacterial populations exposed to free chlorine and monochloramine, representing a metric that possibly better reflects the selective pressures occurring at lower disinfectant levels than MIC. Pairs of phylogenetically similar bacteria were challenged to a range of concentrations of disinfectants. The MSCs of free chlorine and monochloramine were found to range between 0.021 and 0.39 mg L -1 , which were concentrations 1/250 to 1/5 than the MICs of susceptible bacteria (MIC susc ). This study indicates that sub-lethal concentrations of disinfectants could result in the selection of resistant bacterial populations, and MSCs would be a more sensitive indicator of selective pressure, especially in environmental systems.
Gude, Wouter T; van der Veer, Sabine N; van Engen-Verheul, Mariëtte M; de Keizer, Nicolette F; Peek, Niels
2015-01-01
Audit and feedback (A&F) is widely used to aid healthcare professionals in improving clinical performance, but there is little understanding of the underlying mechanism that determines its effectiveness. The aim of this paper is to investigate the process by which healthcare professionals select indicators as improvement targets based on A&F. We performed a laboratory study among 41 healthcare professionals in the context of a web-based A&F intervention designed to improve the quality of cardiac rehabilitation care in the Netherlands. Feedback was provided on eighteen quality indicators, including a score and a colour (representing a recommendation for selection (red and yellow) or non-selection (green)). Indicators with more room for improvement were more likely to be selected, although this varied substantially between participants. In more than a quarter of the cases, participants did not select indicators with obvious room for improvement (yellow or red colour), or selected indicators without apparent room for improvement (green colour). We conclude that personal preferences and beliefs concerning quality and performance targets may dilute the efficiency of A&F.
ERIC Educational Resources Information Center
Brubaker, Harold A.
This study (1) describes student selection and retention procedures currently used by North Central Association colleges and universities which are accredited by the National Council for the Accreditation of Teacher Education, and (2) determines student selection and retention procedures which administrators of teacher education programs at the…
The Social Utility of Performance-Approach Goals in a Selective Educational Environment
ERIC Educational Resources Information Center
Jury, Mickaël; Darnon, Céline; Dompnier, Benoit; Butera, Fabrizio
2017-01-01
According to the recent research, the educational system fulfills both an educational function (i.e., teaching and training students) and a selection function (i.e., determining students' future position in the social hierarchy), particularly in higher education. It has been argued that in the university system the selection function provides a…
An Evolutionary Perspective of Friendship Selection
ERIC Educational Resources Information Center
Coutinho, Savia A.
2007-01-01
The research reported in this article investigates whether promiscuity plays a role in same-sex and opposite-sex friend selection. Since same-sex friends share strong similarity and spend time with their friends' mates or potential mates, it becomes important to select same-sex friends who will not be sexual rivals. One way to determine rivalry in…
7 CFR 58.723 - Basis for selecting cheese for processing.
Code of Federal Regulations, 2011 CFR
2011-01-01
... 7 Agriculture 3 2011-01-01 2011-01-01 false Basis for selecting cheese for processing. 58.723... Service 1 Operations and Operating Procedures § 58.723 Basis for selecting cheese for processing. A... vat of cheese shall have been examined to determine the suitability of the vat for use in process...
7 CFR 58.723 - Basis for selecting cheese for processing.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 7 Agriculture 3 2010-01-01 2010-01-01 false Basis for selecting cheese for processing. 58.723... Service 1 Operations and Operating Procedures § 58.723 Basis for selecting cheese for processing. A... vat of cheese shall have been examined to determine the suitability of the vat for use in process...
DOSESCREEN: a computer program to aid dose placement
Kimberly C. Smith; Jacqueline L. Robertson
1984-01-01
Careful selection of an experimental design for a bioassay substantially improves the precision of effective dose (ED) estimates. Design considerations typically include determination of sample size, dose selection, and allocation of subjects to doses. DOSESCREEN is a computer program written to help investigators select an efficient design for the estimation of an...
Code of Federal Regulations, 2010 CFR
2010-07-01
... Audit and Production Compliance Audit testing, the adequacy of the limits, stops, seals, or other means... (Selective Enforcement Audit and Production Compliance Audit) only the actual settings to which the parameter... Selective Enforcement Audit, adequacy of limits, and physically adjustable ranges. 86.094-22 Section 86.094...
Analysis of Manager Selection and Appointment to Educational Organizations Process in Turkey
ERIC Educational Resources Information Center
Yard?b?, Nursel; Küçük, Fazil
2015-01-01
This study's aim is that to determine the requirements for school principals' selection and assignment conditions and to present these requirements' effects. Qualitative research design was used in this research, and also this study is content analysis research. School principals' selection and assignment conditions in Regulations between the…
Determining the Capacity of Time-Based Selection
ERIC Educational Resources Information Center
Watson, Derrick G.; Kunar, Melina A.
2012-01-01
In visual search, a set of distractor items can be suppressed from future selection if they are presented (previewed) before a second set of search items arrive. This "visual marking" mechanism provides a top-down way of prioritizing the selection of new stimuli, at the expense of old stimuli already in the field (Watson & Humphreys,…
42 CFR 57.306 - Eligibility and selection of nursing student loan applicants.
Code of Federal Regulations, 2011 CFR
2011-10-01
... 42 Public Health 1 2011-10-01 2011-10-01 false Eligibility and selection of nursing student loan... STUDENT LOANS Nursing Student Loans § 57.306 Eligibility and selection of nursing student loan applicants. (a) Determination of eligibility. (1) Applicants are eligible for consideration for a nursing student...
42 CFR 57.306 - Eligibility and selection of nursing student loan applicants.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 42 Public Health 1 2010-10-01 2010-10-01 false Eligibility and selection of nursing student loan... STUDENT LOANS Nursing Student Loans § 57.306 Eligibility and selection of nursing student loan applicants. (a) Determination of eligibility. (1) Applicants are eligible for consideration for a nursing student...
42 CFR 57.306 - Eligibility and selection of nursing student loan applicants.
Code of Federal Regulations, 2012 CFR
2012-10-01
... 42 Public Health 1 2012-10-01 2012-10-01 false Eligibility and selection of nursing student loan... STUDENT LOANS Nursing Student Loans § 57.306 Eligibility and selection of nursing student loan applicants. (a) Determination of eligibility. (1) Applicants are eligible for consideration for a nursing student...
42 CFR 57.306 - Eligibility and selection of nursing student loan applicants.
Code of Federal Regulations, 2013 CFR
2013-10-01
... 42 Public Health 1 2013-10-01 2013-10-01 false Eligibility and selection of nursing student loan... STUDENT LOANS Nursing Student Loans § 57.306 Eligibility and selection of nursing student loan applicants. (a) Determination of eligibility. (1) Applicants are eligible for consideration for a nursing student...
42 CFR 57.306 - Eligibility and selection of nursing student loan applicants.
Code of Federal Regulations, 2014 CFR
2014-10-01
... 42 Public Health 1 2014-10-01 2014-10-01 false Eligibility and selection of nursing student loan... STUDENT LOANS Nursing Student Loans § 57.306 Eligibility and selection of nursing student loan applicants. (a) Determination of eligibility. (1) Applicants are eligible for consideration for a nursing student...
Executive Selection: A Research Report on What Works and What Doesn't.
ERIC Educational Resources Information Center
Sessa, Valerie I.; Kaiser, Robert; Taylor, Jodi K.; Campbell, Richard J.
This book presents a study that examined the apparent failures of many top-level executive selections. For the study, information was gathered from 494 top executives. The research's purpose was to determine how executives are defined as successful or unsuccessful, how executive selection takes place in modern organizations, and what determines…
Dielectrophoresis-based particle sensor using nanoelectrode arrays
NASA Technical Reports Server (NTRS)
Arumugam, Prabhu U. (Inventor); Li, Jun (Inventor); Cassell, Alan M. (Inventor)
2009-01-01
A method for concentrating or partly separating particles of a selected species from a liquid or fluid containing these particles and flowing in a channel, and for determining if the selected species particle is present in the liquid or fluid. A time varying electrical field E, having a root-mean-square intensity E.sup.2.sub.rms with a non-zero gradient in a direction transverse to the liquid or fluid flow direction, is produced by a nanostructure electrode array, with a very high magnitude gradient near exposed electrode tips. A dielectrophoresis force causes the selected particles to accumulate near the electrode tips, if the medium and selected particles have substantially different dielectric constants. An insulating material surrounds most of each of the nanostructure electrodes, and a region of the insulating material surface is functionalized to promote attachment of the selected species particles to the surface. An electrical property value Z(meas) is measured at the functionalized surface and is compared with a reference value Z(ref) to determine if the selected species particles are attached to the functionalized surface.
Active insecticides for Diaphania hyalinata selective for the natural enemy Solenopsis saevissima.
Aguiar, Alex R; Alvarenga, Elson S; Lopes, Mayara C; Santos, Izailda B Dos; Galdino, Tarcisio V; Picanço, Marcelo C
2016-09-01
The objective of this study was to determine the toxicity of the nine synthetic dienamides against the insect pest Diaphania hyalinata (melonworm) and the selectivity of these substances for the predator Solenopsis saevissima (fire ant). Four bioassays were conducted. To begin with, the dienamides that caused high mortality of D. hyalinata have been selected. In the second bioassay the dose-mortality curves of the selected dienamides have been constructed. In the third bioassay, the survival curves for D. hyalinata and the elapsed time to kill 50% of their population have been determined. In the fourth biological test, the selectivity of the substances to the predator S. saevissima has been evaluated. The most active (2E,4E)-N-butylhexa-2,4-dienamide 3d has killed 95% of the melonworm, D. hyalinata, and less than 10% of the natural enemy S. saevissima. The results presented by this compound are superior to the outcome displayed by the commercial insecticide Malathion®. Three of the dienamides prepared in this manuscript have proven to be selective in killing the pest, but not the beneficial insect.
DATA QUALITY OBJECTIVES FOR SELECTING WASTE SAMPLES FOR BENCH-SCALE REFORMER TREATABILITY STUDIES
DOE Office of Scientific and Technical Information (OSTI.GOV)
BANNING DL
2011-02-11
This document describes the data quality objectives to select archived samples located at the 222-S Laboratory for Bench-Scale Reforming testing. The type, quantity, and quality of the data required to select the samples for Fluid Bed Steam Reformer testing are discussed. In order to maximize the efficiency and minimize the time to treat Hanford tank waste in the Waste Treatment and Immobilization Plant, additional treatment processes may be required. One of the potential treatment processes is the fluidized bed steam reformer. A determination of the adequacy of the fluidized bed steam reformer process to treat Hanford tank waste is required.more » The initial step in determining the adequacy of the fluidized bed steam reformer process is to select archived waste samples from the 222-S Laboratory that will be used in a bench scale tests. Analyses of the selected samples will be required to confirm the samples meet the shipping requirements and for comparison to the bench scale reformer (BSR) test sample selection requirements.« less
An ion-selective electrode method for determination of chlorine in geological materials
Aruscavage, P. J.; Campbell, E.Y.
1983-01-01
A method is presented for the determination of chlorine in geological materials, in which a chloride-selective ion electrode is used after decomposition of the sample with hydrofluoric acid and separation of chlorine in a gas-diffusion cell. Data are presented for 30 geological standard materials. The relative standard deviation of the method is estimated to be better than 8% for amounts of chloride of 10 ??g and greater. ?? 1983.
Method and Apparatus for Processing UDP Data Packets
NASA Technical Reports Server (NTRS)
Murphy, Brandon M. (Inventor)
2017-01-01
A method and apparatus for processing a plurality of data packets. A data packet is received. A determination is made as to whether a portion of the data packet follows a selected digital recorder standard protocol based on a header of the data packet. Raw data in the data packet is converted into human-readable information in response to a determination that the portion of the data packet follows the selected digital recorder standard protocol.
Method for determining gene knockouts
Maranas, Costas D [Port Matilda, PA; Burgard, Anthony R [State College, PA; Pharkya, Priti [State College, PA
2011-09-27
A method for determining candidates for gene deletions and additions using a model of a metabolic network associated with an organism, the model includes a plurality of metabolic reactions defining metabolite relationships, the method includes selecting a bioengineering objective for the organism, selecting at least one cellular objective, forming an optimization problem that couples the at least one cellular objective with the bioengineering objective, and solving the optimization problem to yield at least one candidate.
Method for determining gene knockouts
Maranas, Costa D; Burgard, Anthony R; Pharkya, Priti
2013-06-04
A method for determining candidates for gene deletions and additions using a model of a metabolic network associated with an organism, the model includes a plurality of metabolic reactions defining metabolite relationships, the method includes selecting a bioengineering objective for the organism, selecting at least one cellular objective, forming an optimization problem that couples the at least one cellular objective with the bioengineering objective, and solving the optimization problem to yield at least one candidate.
Assfalg, Michael; Gianolio, Eliana; Zanzoni, Serena; Tomaselli, Simona; Russo, Vito Lo; Cabella, Claudia; Ragona, Laura; Aime, Silvio; Molinari, Henriette
2007-11-01
The binding affinities of a selected series of Gd(III) chelates bearing bile acid residues, potential hepatospecific MRI contrast agents, to a liver cytosolic bile acid transporter, have been determined through relaxivity measurements. The Ln(III) complexes of compound 1 were selected for further NMR structural analysis aimed at assessing the molecular determinants of binding. A number of NMR experiments have been carried out on the bile acid-like adduct, using both diamagnetic Y(III) and paramagnetic Gd(III) complexes, bound to a liver bile acid binding protein. The identified protein "hot spots" defined a single binding site located at the protein portal region. The presented findings will serve in a medicinal chemistry approach for the design of hepatocytes-selective gadolinium chelates for liver malignancies detection.
Kramer, S; Blaschke, G
2001-02-10
A sensitive high-performance liquid chromatographic method has been developed for the determination of the beta2-selective adrenergic agonist fenoterol in human plasma. To improve the sensitivity of the method, fenoterol was derivatized with N-(chloroformyl)-carbazole prior to HPLC analysis yielding highly fluorescent derivatives. The assay involves protein precipitation with acetonitrile, liquid-liquid-extraction of fenoterol from plasma with isobutanol under alkaline conditions followed by derivatization with N-(chloroformyl)-carbazole. Reversed-phase liquid chromatographic determination of the fenoterol derivative was performed using a column-switching system consisting of a LiChrospher 100 RP 18 and a LiChrospher RP-Select B column with acetonitrile, methanol and water as mobile phase. The limit of quantitation in human plasma was 376 pg fenoterol/ml. The method was successfully applied for the assay of fenoterol in patient plasma.
Feng, Zufei; Lu, Yan; Zhao, Yingjuan; Ye, Helin
2017-11-02
On the basis of magnetic molecularly imprinted polymer (MMIP) solid-phase extraction coupled with high performance liquid chromatography, we established a new method for the determination of the 4-methylimidazole (4-MEI) in soy sauce. Scanning electron microscopy (SEM), Fourier transform infrared (FT-IR), X-ray diffraction (XRD) and vibrating sample magnetometer (VSM) were used to characterize the synthesized MMIPs. To evaluate the polymers, batch rebinding experiments were carried out. The binding strength and capacity were determined from the derived Freundlich isotherm (FI) equation. The selective recognition capability of MMIPs was investigated with a reference compound and a structurally similar compound. As a selective pre-concentration sorbents for 4-methylimidazole in soy sauce, the MMIPs showed a satisfied recoveries rate of spiked samples, ranged from 97% to 105%. As a result, the prepared MMIPs could be applied to selectively pre-concentrate and determine 4-methylimidazole in soy sauce samples.
Biernacka, Joanna; Betlejewska-Kielak, Katarzyna; Kłosińska-Szmurło, Ewa; Pluciński, Franciszek A; Mazurek, Aleksander P
2013-01-01
The physicochemical properties relevant to biological activity of selected bisphosphonates such as clodronate disodium salt, etidronate disodium salt, pamidronate disodium salt, alendronate sodium salt, ibandronate sodium salt, risedronate sodium salt and zoledronate disodium salt were determined using in silico methods. The main aim of our research was to investigate and propose molecular determinants thataffect bioavailability of above mentioned compounds. These determinants are: stabilization energy (deltaE), free energy of solvation (deltaG(solv)), electrostatic potential, dipole moment, as well as partition and distribution coefficients estimated by the log P and log D values. Presented values indicate that selected bisphosphonates a recharacterized by high solubility and low permeability. The calculated parameters describing both solubility and permeability through biological membranes seem to be a good bioavailability indicators of bisphosphonates examined and can be a useful tool to include into Biopharmaceutical Classification System (BCS) development.
El Hamshary, Marwa S; Salem, Omar H; El Nashar, Rasha M
2010-01-01
Two ion-selective sensors of the plastic membrane type were prepared for the determination of oxybutynin hydrochloride (OxCl). They depend on the incorporation of the ion-associates with phosphotungestic acid or phosphomolybdic acid in a PVC matrix. A comparative study is made between their performance characteristics in batch and FIA conditions. The sensors have nearly the same usable concentration, temperature and pH range. They have a wide range of selectivity and can be applied for the determination of the relevant drug with nearly the same precision and accuracy in vitro. Dissolution testing was applied using the sensors; this offers a simple, rapid, cheap way out of sophisticated and high cost instruments used in the pharmacopeial method using HPLC. The investigated drug was determined in its pure and pharmaceutical preparations. The results were accurate and precise, as indicated by the recovery values and coefficients of variation.
ERIC Educational Resources Information Center
Peterson, Sharon; Duncan, Diana Poovey; Null, Dawn Bloyd; Roth, Sara Long; Gill, Lynn
2010-01-01
Objective: Determine the effects of a short-term, multi-faceted, point-of-selection intervention on college students' perceptions and selection of 10 targeted healthful foods in a university dining hall and changes in their self-reported overall eating behaviors. Participants: 104 college students, (age 18-23) completed pre-I and post-I surveys.…
Deng, Changjian; Lv, Kun; Shi, Debo; Yang, Bo; Yu, Song; He, Zhiyi; Yan, Jia
2018-06-12
In this paper, a novel feature selection and fusion framework is proposed to enhance the discrimination ability of gas sensor arrays for odor identification. Firstly, we put forward an efficient feature selection method based on the separability and the dissimilarity to determine the feature selection order for each type of feature when increasing the dimension of selected feature subsets. Secondly, the K-nearest neighbor (KNN) classifier is applied to determine the dimensions of the optimal feature subsets for different types of features. Finally, in the process of establishing features fusion, we come up with a classification dominance feature fusion strategy which conducts an effective basic feature. Experimental results on two datasets show that the recognition rates of Database I and Database II achieve 97.5% and 80.11%, respectively, when k = 1 for KNN classifier and the distance metric is correlation distance (COR), which demonstrates the superiority of the proposed feature selection and fusion framework in representing signal features. The novel feature selection method proposed in this paper can effectively select feature subsets that are conducive to the classification, while the feature fusion framework can fuse various features which describe the different characteristics of sensor signals, for enhancing the discrimination ability of gas sensors and, to a certain extent, suppressing drift effect.
A probabilistic method for testing and estimating selection differences between populations.
He, Yungang; Wang, Minxian; Huang, Xin; Li, Ran; Xu, Hongyang; Xu, Shuhua; Jin, Li
2015-12-01
Human populations around the world encounter various environmental challenges and, consequently, develop genetic adaptations to different selection forces. Identifying the differences in natural selection between populations is critical for understanding the roles of specific genetic variants in evolutionary adaptation. Although numerous methods have been developed to detect genetic loci under recent directional selection, a probabilistic solution for testing and quantifying selection differences between populations is lacking. Here we report the development of a probabilistic method for testing and estimating selection differences between populations. By use of a probabilistic model of genetic drift and selection, we showed that logarithm odds ratios of allele frequencies provide estimates of the differences in selection coefficients between populations. The estimates approximate a normal distribution, and variance can be estimated using genome-wide variants. This allows us to quantify differences in selection coefficients and to determine the confidence intervals of the estimate. Our work also revealed the link between genetic association testing and hypothesis testing of selection differences. It therefore supplies a solution for hypothesis testing of selection differences. This method was applied to a genome-wide data analysis of Han and Tibetan populations. The results confirmed that both the EPAS1 and EGLN1 genes are under statistically different selection in Han and Tibetan populations. We further estimated differences in the selection coefficients for genetic variants involved in melanin formation and determined their confidence intervals between continental population groups. Application of the method to empirical data demonstrated the outstanding capability of this novel approach for testing and quantifying differences in natural selection. © 2015 He et al.; Published by Cold Spring Harbor Laboratory Press.
Resealing concrete pavement joints
DOT National Transportation Integrated Search
1999-07-01
The primary objective of this study was to evaluate the relative performance of the selected joint sealant materials. Other objectives were to determine the effect of selected sealant configurations and installation methods, and to identify sealant m...
Alternate working fluids for solar air conditioning applications
NASA Technical Reports Server (NTRS)
Evans, R. D.; Beck, J. K.
1978-01-01
An experimental investigation of sixteen different refrigerant-absorbent fluid pairs has been carried out in order to determine their suitability as the working fluid in a solar-powered absorption cycle air conditioner. The criteria used in the initial selection of a refrigerant-absorbent pair included: high affinity (large negative deviation from Raoult's Law), high solubility, low specific heat, low viscosity, stability, corrosive properties, safety, and cost. For practical solar considerations of a fluid pair, refrigerants were selected with low boiling points whereas absorbent fluids were selected with a boiling point considerably above that of the refrigerant. Additional restrictions are determined by the operating temperatures of the absorber and the generator; these temperatures were specified as 100 F (39 C) and 170 F (77 C). Data are presented for a few selected pressures at the specified absorber and generator temperatures.
Evaluation of monograph selection in a health sciences library.
Fenske, R E
1994-01-01
This article reports on an evaluation of recent monograph selections in a small academic health sciences library. Actual use of each new book was determined from date-due slips. Data were analyzed by broad subject, discipline, and number of uses. The startling result was that more than 60% of recent selections had been used little or not at all. To determine factors affecting use, the author examined aggregate data, used intuition, and assessed the raw data in more detail. Recommendations made to management were approved and implemented. The study bolstered confidence that it is possible to select materials with the highest potential for use and to depend on remote access for other needed works. It is suggested that other health sciences libraries undertake such studies and question the need to strive for comprehensive collections. PMID:7920335
Consequences of plant-chemical diversity for domestic goat food preference in Mediterranean forests
NASA Astrophysics Data System (ADS)
Baraza, Elena; Hódar, José A.; Zamora, Regino
2009-01-01
The domestic goat, a major herbivore in the Mediterranean basin, has demonstrated a strong ability to adapt its feeding behaviour to the chemical characteristics of food, selecting plants according to their nutritive quality. In this study, we determine some chemical characteristics related to plant nutritional quality and its variability among and within five tree species, these being the main components of the mountain forests of SE Spain, with the aim of determining their influence on food selection by this generalist herbivore. We analyse nitrogen, total phenols, condensed tannins and fibre concentration as an indicator of the nutritive value of the different trees. To determine the preference by the domestic goat, we performed two types of feeding-choice assays, where goats had to select between different species or between branches of the same species but from trees of different nutritional quality. The analysis of the plant nutritional quality showed significant differences in the chemical characteristics between species, and a high variability within species. However, when faced with different tree species, the domestic goat selected some of them but showed striking individual differences between goats. When selecting between trees of the same species, the goats showed no differential selection. This limited effect of chemical plant characteristics, together with the variability in foraging behaviour, resulted in a widespread consumption of diverse plant species, which can potentially modulate the effect of the goat on vegetation composition, and open the way for the conservation of traditional livestock grazing on natural protected areas.
NASA Astrophysics Data System (ADS)
Marfuah; Widiantoro, Suryo
2017-12-01
Universal University of Batam offers outstanding achievement scholarship to the current students to be each year of new academic year, seeing the large number of new Students who are interested to get it then the selection team should be able to filter and choose the eligible ones. The selection process starting with evaluation and judgement made by the experts. There were five criteria as the basic of selection and each had three alternatives that must be considered. Based on the policy of University the maximum number of recipients are five for each of six study programs. Those programs are art of music, dance, industrial engineering, environmental engineering, telecommunication engineering, and software engineering. The expert choice was subjective that AHP method was used to help in making decision consistently by doing pairwise comparison matrix process between criteria based on selected alternatives, by determining the priority order of criteria and alternatives used. The results of these calculations were used as supporting decision-making to determine the eligible students receiving scholarships based on alternatives of selected criteria determined by the final results of AHP method calculation with the priority criterion A (0.37%), C (0.23%), E (0.21%), D (0.14%) and B (0.06%), value of consistency ratio 0.05. Then the alternative priorities 1 (0.63), 2 (0.26) and 3 (0.11) the consistency ratio values 0.03, where each CR ≤ 0.1 or consistent weighting preference.
Does a selection interview predict year 1 performance in dental school?
McAndrew, R; Ellis, J; Valentine, R A
2017-05-01
It is important for dental schools to select students who will complete their degree and progress on to become the dentists of the future. The process should be transparent, fair and ethical and utilise selection tools that select appropriate students. The interview is an integral part of UK dental schools student selection procedures. This study was undertaken in order to determine whether different interview methods (Cardiff with a multiple mini interview and Newcastle with a more traditional interview process) along with other components used in selection predicted academic performance in students. The admissions selection data for two dental schools (Cardiff and Newcastle) were collected and analysed alongside student performance in academic examinations in Year 1 of the respective schools. Correlation statistics were used to determine whether selection tools had any relevance to academic performance once students were admitted to their respective Universities. Data was available for a total of 177 students (77 Cardiff and 100 Newcastle). Examination performance did not correlate with admission interview scores at either school; however UKCAT score was linked to poor academic performance. Although interview methodology does not appear to correlate with academic performance it remains an integral and very necessary part of the admissions process. Ultimately schools need to be comfortable with their admissions procedures in attracting and selecting the calibre of students they desire. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Restricted cross-scale habitat selection by American beavers.
Francis, Robert A; Taylor, Jimmy D; Dibble, Eric; Strickland, Bronson; Petro, Vanessa M; Easterwood, Christine; Wang, Guiming
2017-12-01
Animal habitat selection, among other ecological phenomena, is spatially scale dependent. Habitat selection by American beavers Castor canadensis (hereafter, beaver) has been studied at singular spatial scales, but to date no research addresses multi-scale selection. Our objectives were to determine if beaver habitat selection was specialized to semiaquatic habitats and if variables explaining habitat selection are consistent between landscape and fine spatial scales. We built maximum entropy (MaxEnt) models to relate landscape-scale presence-only data to landscape variables, and used generalized linear mixed models to evaluate fine spatial scale habitat selection using global positioning system (GPS) relocation data. Explanatory variables between the landscape and fine spatial scale were compared for consistency. Our findings suggested that beaver habitat selection at coarse (study area) and fine (within home range) scales was congruent, and was influenced by increasing amounts of woody wetland edge density and shrub edge density, and decreasing amounts of open water edge density. Habitat suitability at the landscape scale also increased with decreasing amounts of grass frequency. As territorial, central-place foragers, beavers likely trade-off open water edge density (i.e., smaller non-forested wetlands or lodges closer to banks) for defense and shorter distances to forage and obtain construction material. Woody plants along edges and expanses of open water for predator avoidance may limit beaver fitness and subsequently determine beaver habitat selection.
Female mating preferences determine system-level evolution in a gene network model.
Fierst, Janna L
2013-06-01
Environmental patterns of directional, stabilizing and fluctuating selection can influence the evolution of system-level properties like evolvability and mutational robustness. Intersexual selection produces strong phenotypic selection and these dynamics may also affect the response to mutation and the potential for future adaptation. In order to to assess the influence of mating preferences on these evolutionary properties, I modeled a male trait and female preference determined by separate gene regulatory networks. I studied three sexual selection scenarios: sexual conflict, a Gaussian model of the Fisher process described in Lande (in Proc Natl Acad Sci 78(6):3721-3725, 1981) and a good genes model in which the male trait signalled his mutational condition. I measured the effects these mating preferences had on the potential for traits and preferences to evolve towards new states, and mutational robustness of both the phenotype and the individual's overall viability. All types of sexual selection increased male phenotypic robustness relative to a randomly mating population. The Fisher model also reduced male evolvability and mutational robustness for viability. Under good genes sexual selection, males evolved an increased mutational robustness for viability. Females choosing their mates is a scenario that is sufficient to create selective forces that impact genetic evolution and shape the evolutionary response to mutation and environmental selection. These dynamics will inevitably develop in any population where sexual selection is operating, and affect the potential for future adaptation.
Restricted cross-scale habitat selection by American beavers
Taylor, Jimmy D; Dibble, Eric; Strickland, Bronson; Petro, Vanessa M; Easterwood, Christine; Wang, Guiming
2017-01-01
Abstract Animal habitat selection, among other ecological phenomena, is spatially scale dependent. Habitat selection by American beavers Castor canadensis (hereafter, beaver) has been studied at singular spatial scales, but to date no research addresses multi-scale selection. Our objectives were to determine if beaver habitat selection was specialized to semiaquatic habitats and if variables explaining habitat selection are consistent between landscape and fine spatial scales. We built maximum entropy (MaxEnt) models to relate landscape-scale presence-only data to landscape variables, and used generalized linear mixed models to evaluate fine spatial scale habitat selection using global positioning system (GPS) relocation data. Explanatory variables between the landscape and fine spatial scale were compared for consistency. Our findings suggested that beaver habitat selection at coarse (study area) and fine (within home range) scales was congruent, and was influenced by increasing amounts of woody wetland edge density and shrub edge density, and decreasing amounts of open water edge density. Habitat suitability at the landscape scale also increased with decreasing amounts of grass frequency. As territorial, central-place foragers, beavers likely trade-off open water edge density (i.e., smaller non-forested wetlands or lodges closer to banks) for defense and shorter distances to forage and obtain construction material. Woody plants along edges and expanses of open water for predator avoidance may limit beaver fitness and subsequently determine beaver habitat selection. PMID:29492032
Temporary site selection and decision-making methods: a case study of Tehran, Iran.
Omidvar, Babak; Baradaran-Shoraka, Mohammad; Nojavan, Mehdi
2013-07-01
Decisions on selecting an appropriate site for temporary shelter used to be taken in a limited amount of time after a disaster. The need for a systematic method in this area inspired the MADM (multi-attribute decision making) for complex disaster management decisions. This research proposes a model for appropriate and systematic site selection for temporary shelters, before an earthquake, using a geographical information system and MADM based on an earthquake damage assessment. After the effective criteria for site selection of temporary shelters are determined, the geographical layers of these criteria are prepared for Municipal District No.1 of Greater Tehran, the capital of Iran. Given these attributes and the required shelter area (415-610 hectares), 14 zones are proposed initially. Various MADM methods are used for the final selection. The mean of the aggregated ranking results are determined, and 10 of the 14 initial zones are ranked. © 2013 The Author(s). Journal compilation © Overseas Development Institute, 2013.
Magnetically separable polymer (Mag-MIP) for selective analysis of biotin in food samples.
Uzuriaga-Sánchez, Rosario Josefina; Khan, Sabir; Wong, Ademar; Picasso, Gino; Pividori, Maria Isabel; Sotomayor, Maria Del Pilar Taboada
2016-01-01
This work presents an efficient method for the preparation of magnetic nanoparticles modified with molecularly imprinted polymers (Mag-MIP) through core-shell method for the determination of biotin in milk food samples. The functional monomer acrylic acid was selected from molecular modeling, EGDMA was used as cross-linking monomer and AIBN as radical initiator. The Mag-MIP and Mag-NIP were characterized by FTIR, magnetic hysteresis, XRD, SEM and N2-sorption measurements. The capacity of Mag-MIP for biotin adsorption, its kinetics and selectivity were studied in detail. The adsorption data was well described by Freundlich isotherm model with adsorption equilibrium constant (KF) of 1.46 mL g(-1). The selectivity experiments revealed that prepared Mag-MIP had higher selectivity toward biotin compared to other molecules with different chemical structure. The material was successfully applied for the determination of biotin in diverse milk samples using HPLC for quantification of the analyte, obtaining the mean value of 87.4% recovery. Copyright © 2015 Elsevier Ltd. All rights reserved.
Laurenson, Yan C S M; Kyriazakis, Ilias; Bishop, Stephen C
2013-10-18
Estimated breeding values (EBV) for faecal egg count (FEC) and genetic markers for host resistance to nematodes may be used to identify resistant animals for selective breeding programmes. Similarly, targeted selective treatment (TST) requires the ability to identify the animals that will benefit most from anthelmintic treatment. A mathematical model was used to combine the concepts and evaluate the potential of using genetic-based methods to identify animals for a TST regime. EBVs obtained by genomic prediction were predicted to be the best determinant criterion for TST in terms of the impact on average empty body weight and average FEC, whereas pedigree-based EBVs for FEC were predicted to be marginally worse than using phenotypic FEC as a determinant criterion. Whilst each method has financial implications, if the identification of host resistance is incorporated into a wider genomic selection indices or selective breeding programmes, then genetic or genomic information may be plausibly included in TST regimes. Copyright © 2013 Elsevier B.V. All rights reserved.
The lepton+jets Selection and Determination of the Lepton Fake Rate with the Full RunIIb Data Set
DOE Office of Scientific and Technical Information (OSTI.GOV)
Meister, Daniel
2013-01-01
This thesis presents the combined single top andmore » $$ t\\overline{ }\\ t $$ lepton+jets selection for the full RunIIb dataset of the DØ detector. The selection uses the newest soft- ware versions including all standard central object identifications and corrections and has various additions and improvements compared to the previous 7 . 3 fb - 1 $$ t\\overline{ }\\ t $$ selection and the previous single top selection in order to accommodate even more different analyses. The lepton fake rate $$\\epsilon_{\\rm QCD}$$ and the real lepton efficiency $$\\epsilon_{\\rm sig}$$ are estimated using the matrix method and different variations are considered in order to determine the systematic errors. The calculation has to be done for each run period and every set of analysis cuts separately. In addition the values for the exclusive jet bins and for the new single top analysis cuts have been derived and the thesis shows numerous control plots to demonstrate the excellent agreement between data and Monte Carlo.« less
Selective etching of TiN over TaN and vice versa in chlorine-containing plasmas
DOE Office of Scientific and Technical Information (OSTI.GOV)
Shin, Hyungjoo; Zhu Weiye; Liu Lei
2013-05-15
Selectivity of etching between physical vapor-deposited TiN and TaN was studied in chlorine-containing plasmas, under isotropic etching conditions. Etching rates for blanket films were measured in-situ using optical emission of the N{sub 2} (C{sup 3}{Pi}{sub u}{yields}B{sup 3}{Pi}{sub g}) bandhead at 337 nm to determine the etching time, and transmission electron microscopy to determine the starting film thickness. The etching selectivity in Cl{sub 2}/He or HCl/He plasmas was poor (<2:1). There was a window of very high selectivity of etching TiN over TaN by adding small amounts (<1%) of O{sub 2} in the Cl{sub 2}/He plasma. Reverse selectivity (10:1 of TaNmore » etching over TiN) was observed when adding small amounts of O{sub 2} to the HCl/He plasma. Results are explained on the basis of the volatility of plausible reaction products.« less
Survey to Determine Flight Plan Data and Flight Scheduling Accuracy
DOT National Transportation Integrated Search
1972-01-01
This survey determined Operational Flight Plan Data and Flight schduling accuracy vs. published schedules an/or stored flight plan data. This accuracy was determined by sampling tracer flights of varying lengths, selected terminals, and high altitude...
20 CFR 416.1413a - Reconsiderations of initial determinations on applications.
Code of Federal Regulations, 2011 CFR
2011-04-01
... conference, and will reach our reconsidered determination on the basis of the review you select. (b) Medical... presumed you were blind or disabled), we shall reach our reconsidered determination on the basis of a case...
Soldatkin, O O; Peshkova, V M; Saiapina, O Y; Kucherenko, I S; Dudchenko, O Y; Melnyk, V G; Vasylenko, O D; Semenycheva, L M; Soldatkin, A P; Dzyadevych, S V
2013-10-15
The aim of this work was to develop an array of biosensors for simultaneous determination of four carbohydrates in solution. Several enzyme systems selective to lactose, maltose, sucrose and glucose were immobilised on the surface of four conductometric transducers and served as bio-recognition elements of the biosensor array. Direct enzyme analysis carried out by the developed biosensors was highly sensitive to the corresponding substrates. The analysis lasted 2 min. The dynamic range of substrate determination extended from 0.001 mM to 1.0-3.0mM, and strongly depended on the enzyme system used. An effect of the solution pH, ionic strength and buffer capacity on the biosensors responses was investigated; the conditions of simultaneous operation of all biosensors were optimised. The data on cross-impact of the substrates of all biosensors were obtained; the biosensor selectivity towards possible interfering carbohydrates was tested. The developed biosensor array showed good signal reproducibility and storage stability. The biosensor array is suited for simultaneous, quick, simple, and selective determination of maltose, lactose, sucrose and glucose. © 2013 Elsevier B.V. All rights reserved.
Employee choice of a high-deductible health plan across multiple employers.
Lave, Judith R; Men, Aiju; Day, Brian T; Wang, Wei; Zhang, Yuting
2011-02-01
To determine factors associated with selecting a high-deductible health plan (HDHP) rather than a preferred provider plan (PPO) and to examine switching and market segmentation after initial selection. Claims and benefit information for 2005-2007 from nine employers in western Pennsylvania first offering HDHP in 2006. We examined plan growth over time, used logistic regression to determine factors associated with choosing an HDHP, and examined the distribution of healthy and sick members across plan types. We linked employees with their dependents to determine family-level variables. We extracted risk scores, covered charges, employee age, and employee gender from claims data. We determined census-level race, education, and income information. Health status, gender, race, and education influenced the type of individual and family policies chosen. In the second year the HDHP was offered, few employees changed plans. Risk segmentation between HDHPs and PPOs existed, but it did not increase. When given a choice, those who are healthier are more likely to select an HDHP leading to risk segmentation. Risk segmentation did not increase in the second year that HDHPs were offered. © Health Research and Educational Trust.
Grahn, A.R.
1993-05-11
A force sensor and related method for determining force components is described. The force sensor includes a deformable medium having a contact surface against which a force can be applied, a signal generator for generating signals that travel through the deformable medium to the contact surface, a signal receptor for receiving the signal reflected from the contact surface, a generation controller, a reception controller, and a force determination apparatus. The signal generator has one or more signal generation regions for generating the signals. The generation controller selects and activates the signal generation regions. The signal receptor has one or more signal reception regions for receiving signals and for generating detections signals in response thereto. The reception controller selects signal reception regions and detects the detection signals. The force determination apparatus measures signal transit time by timing activation and detection and, optionally, determines force components for selected cross-field intersections. The timer which times by activation and detection can be any means for measuring signal transit time. A cross-field intersection is defined by the overlap of a signal generation region and a signal reception region.
Grahn, Allen R.
1993-01-01
A force sensor and related method for determining force components. The force sensor includes a deformable medium having a contact surface against which a force can be applied, a signal generator for generating signals that travel through the deformable medium to the contact surface, a signal receptor for receiving the signal reflected from the contact surface, a generation controller, a reception controller, and a force determination apparatus. The signal generator has one or more signal generation regions for generating the signals. The generation controller selects and activates the signal generation regions. The signal receptor has one or more signal reception regions for receiving signals and for generating detections signals in response thereto. The reception controller selects signal reception regions and detects the detection signals. The force determination apparatus measures signal transit time by timing activation and detection and, optionally, determines force components for selected cross-field intersections. The timer which times by activation and detection can be any means for measuring signal transit time. A cross-field intersection is defined by the overlap of a signal generation region and a signal reception region.
Potentiometric sensors for the selective determination of sulbutiamine.
Ahmed, M A; Elbeshlawy, M M
1999-11-01
Five novel polyvinyl chloride (PVC) matrix membrane sensors for the selective determination of sulbutiamine (SBA) cation are described. These sensors are based on molybdate, tetraphenylborate, reineckate, phosphotun gestate and phosphomolybdate, as possible ion-pairing agents. These sensors display rapid near-Nernstian stable response over a relatively wide concentration range 1x10(-2)-1x10(-6) M of sulbutiamine, with calibration slopes 28 32.6 mV decade(-1) over a reasonable pH range 2-6. The proposed sensors proved to have a good selectivity for SBA over some inorganic and organic cations. The five potentiometric sensors were applied successfully in the determination of SBA in a pharmaceutical preparation (arcalion-200) using both direct potentiometry and potentiometric titration. Direct potentiometric determination of microgram quantities of SBA gave average recoveries of 99.4 and 99.3 with mean standard deviation of 0.7 and 0.3 for pure SBA and arcalion-200 formulation respectively. Potentiometric titration of milligram quantities of SBA gave average recoveries of 99.3 and 98.7% with mean standard deviation of 0.7 and 1.2 for pure SBA and arcalion-200 formulation, respectively.
Sexual conflict resolved by invasion of a novel sex determiner in Lake Malawi cichlid fishes.
Roberts, Reade B; Ser, Jennifer R; Kocher, Thomas D
2009-11-13
Sex determination mechanisms differ among animal species, but it is not clear how these differences evolve. New sex determiners may arise in response to sexual conflicts, which occur when traits benefit one sex but hinder the other. We identified the genetic basis for the orange-blotch (OB) color pattern, a trait under sexually antagonistic selection in the cichlid fish of Lake Malawi, East Africa. The OB phenotype is due to a cis-regulatory mutation in the Pax7 gene. OB provides benefits of camouflage to females but disrupts the species-specific male color patterns used for mate recognition. We suggest that the resulting sexual conflict over the OB allele has been resolved by selection for a novel female sex determination locus that has invaded populations with an ancestral male sex determination system.
McEwen, Jamie R; Vamosi, Jana C; Rogers, Sean M
2013-01-01
Population differentiation can be driven in large part by natural selection, but selectively neutral evolution can play a prominent role in shaping patters of population divergence. The decomposition of the evolutionary history of populations into the relative effects of natural selection and selectively neutral evolution enables an understanding of the causes of population divergence and adaptation. In this study, we examined heterogeneous genomic divergence between alpine and lowland ecotypes of the allopolyploid plant, Anemone multifida. Using peak height and dominant AFLP data, we quantified population differentiation at non-outlier (neutral) and outlier loci to determine the potential contribution of natural selection and selectively neutral evolution to population divergence. We found 13 candidate loci, corresponding to 2.7% of loci, with signatures of divergent natural selection between alpine and lowland populations and between alpine populations (Fst = 0.074-0.445 at outlier loci), but neutral population differentiation was also evident between alpine populations (FST = 0.041-0.095 at neutral loci). By examining population structure at both neutral and outlier loci, we determined that the combined effects of selection and neutral evolution are associated with the divergence of alpine populations, which may be linked to extreme abiotic conditions and isolation between alpine sites. The presence of outlier levels of genetic variation in structured populations underscores the importance of separately analyzing neutral and outlier loci to infer the relative role of divergent natural selection and neutral evolution in population divergence.
48 CFR 333.104 - Protests to GAO.
Code of Federal Regulations, 2010 CFR
2010-10-01
... a stop work order has been issued.) (I) A copy of any mutual agreement to suspend work on a no-cost... determination. (N) The acquisition plan, source selection plan, and the source selection decision document. (O...
48 CFR 333.104 - Protests to GAO.
Code of Federal Regulations, 2011 CFR
2011-10-01
... a stop work order has been issued.) (I) A copy of any mutual agreement to suspend work on a no-cost... determination. (N) The acquisition plan, source selection plan, and the source selection decision document. (O...
Physical studies of asteroids. XXXII. Rotation periods and UBVRI-colours for selected asteroids
NASA Astrophysics Data System (ADS)
Piironen, J.; Lagerkvist, C.-I.; Erikson, A.; Oja, T.; Magnusson, P.; Festin, L.; Nathues, A.; Gaul, M.; Velichko, F.
1998-03-01
We present lightcurves of selected asteroids. Most of the asteroids were included to obtain refined spin periods. Enhanced periods were determined for 11 Parthenope, 306 Unitas and 372 Palma. We confirmed the spin periods of 8 Flora, 13 Egeria, 71 Niobe, 233 Asterope, 291 Alice, 409 Aspasia, 435 Ella and 512 Taurinensis. We determined also BV-colours for most of the included asteroids and UBVRI-colours for a total of 22 asteroids.
Determination of Selected Amino Acids in Serum of Patients with Liver Disease.
Kanďár, Roman; Drábková, Petra; Toiflová, Tereza; Čegan, Alexander
2016-01-01
The determination of amino acids can be a reliable approach for extended diagnosis of liver diseases. This is because liver disease can be a cause of impaired amino acid metabolism. Therefore, a method for the determination of serum amino acids, applicable for clinical purposes, is necessary. The aim of this study was to find differences in the levels of selected amino acids between patients with liver disease and a control group. Samples of peripheral venous blood were obtained from a group of patients with liver disease (n = 131, 59 women at an average age of 60 years and 72 men at an average age of 52 years) and a control group (n = 105, 47 women at an average age of 62 years and 58 men at an average age of 58 years). Before the separation, the amino acids were derivatized with naphthalene-2,3-dicarboxaldehyde. For the separation, reverse phase column was used. The effluent was monitored with a fluorescence detector. There were significant differences in the concentrations of some amino acids between the patients and the control group, but also between women and men. Correlations between some amino acids and markers of liver blood tests and lipid metabolism were observed. A simple, relatively rapid and selective HPLC method with fluorescence detection for the determination of selected amino acids in serum has been developed.
Concurrent Working Memory Load Can Facilitate Selective Attention: Evidence for Specialized Load
ERIC Educational Resources Information Center
Park, Soojin; Kim, Min-Shik; Chun, Marvin M.
2007-01-01
Load theory predicts that concurrent working memory load impairs selective attention and increases distractor interference (N. Lavie, A. Hirst, J. W. de Fockert, & E. Viding, see record 2004-17825-003). Here, the authors present new evidence that the type of concurrent working memory load determines whether load impairs selective attention or not.…
The Empirical Selection of Anchor Items Using a Multistage Approach
ERIC Educational Resources Information Center
Craig, Brandon
2017-01-01
The purpose of this study was to determine if using a multistage approach for the empirical selection of anchor items would lead to more accurate DIF detection rates than the anchor selection methods proposed by Kopf, Zeileis, & Strobl (2015b). A simulation study was conducted in which the sample size, percentage of DIF, and balance of DIF…
Resource selection by Indiana bats during the maternity season
Kathryn M. Womack; Sybill K. Amelon; Frank R. Thompson
2013-01-01
Little information exists on resource selection by foraging Indiana bats (Myotis sodalis) during the maternity season. Existing studies are based on modest sample sizes because of the rarity of this endangered species and the difficulty of radio-tracking bats. Our objectives were to determine resource selection by foraging Indiana bats during the maternity season and...
ERIC Educational Resources Information Center
Hafner, Lawrence E.
A study developed a multiple regression prediction equation for each of six selected achievement variables in a popular standardized test of achievement. Subjects, 42 fourth-grade pupils randomly selected across several classes in a large elementary school in a north Florida city, were administered several standardized tests to determine predictor…
ERIC Educational Resources Information Center
Griessman, B. Eugene; Bertrand, Alvin L.
Two rural Louisiana communities were selected to evaluate the effectiveness of certain types of communication in preventing man-caused forest fires. The communities were selected on the basis of differences in fire occurrence rates and other factors related to conservation. Questionnaires and personal interviews were utilized to determine views of…
Reconfigurable antenna pattern verification
NASA Technical Reports Server (NTRS)
Drexler, Jerome P. (Inventor); Becker, Robert C. (Inventor); Meyers, David W. (Inventor); Muldoon, Kelly P. (Inventor)
2013-01-01
A method of verifying programmable antenna configurations is disclosed. The method comprises selecting a desired antenna configuration from a plurality of antenna configuration patterns, with the selected antenna configuration forming at least one reconfigurable antenna from reconfigurable antenna array elements. The method validates the formation of the selected antenna configuration to determine antenna performance of the at least one reconfigurable antenna.
ERIC Educational Resources Information Center
Gordon-Salant, Sandra; Fitzgibbons, Peter J.; Friedman, Sarah A.
2007-01-01
Purpose: The goal of this experiment was to determine whether selective slowing of speech segments improves recognition performance by young and elderly listeners. The hypotheses were (a) the benefits of time expansion occur for rapid speech but not for natural-rate speech, (b) selective time expansion of consonants produces greater score…
The Effects of Selective Attention to Television Forms on Children's Comprehension of Content.
ERIC Educational Resources Information Center
Calvert, Sandra L.; And Others
The purposes of this study were to provide information about how formal features of television are related to children's selective attention and to determine how selective attention is related, in turn, to comprehension of content. Formal features are defined as attributes of television productions that are relatively content-free and that result…
Gene-assisted selection: applications of association genetics for forest tree breeding
Philip L. Wilcox; Craig E. Echt; Rowland D. Burdon
2007-01-01
This chapter describes application of association genetics in forest tree species for the purposes of selection. We use the term gene-assisted selection (GAS) to denote application of marker-trait associations determined via association genetics, which we anticipate will be based on poly morph isms associated with expressed genes. The salient features of forest trees...
An Easily Constructed Salicylate-Ion-Selective Electrode for Use in the Instructional Laboratory.
ERIC Educational Resources Information Center
Creager, Stephen E.; And Others
1995-01-01
Describes an electrode, selective for the salicylate ion, that can be prepared and used by undergraduate students. Discusses the preparation of the electrode, typical response characteristics obtained, and results of a limited study using the electrode to estimate the selectivity coefficient for an interfering ion and to determine the amount of…
Stamey, Timothy C.
2001-01-01
In 1999, the U.S. Geological Survey, in cooperation with the U.S. Army Signal Center and Fort Gordon, began collection of periodic streamflow data at four streams on the military base to assess and estimate streamflow characteristics of those streams for potential water-supply sources. Simple and reliable methods of determining streamflow characteristics of selected streams on the military base are needed for the initial implementation of the Fort Gordon Integrated Natural Resources Management Plan. Long-term streamflow data from the Butler Creek streamflow gaging station were used along with several concurrent discharge measurements made at three selected partial-record streamflow stations on Fort Gordon to determine selected low-flow streamflow characteristics. Streamflow data were collected and analyzed using standard U.S. Geological Survey methods and computer application programs to verify the use of simple drainage area to discharge ratios, which were used to estimate the low-flow characteristics for the selected streams. Low-flow data computed based on daily mean streamflow include: mean discharges for consecutive 1-, 3-, 7-, 14-, and 30-day period and low-flow estimates of 7Q10, 30Q2, 60Q2, and 90Q2 recurrence intervals. Flow-duration data also were determined for the 10-, 30-, 50-, 70-, and 90-percent exceedence flows. Preliminary analyses of the streamflow indicate that the flow duration and selected low-flow statistics for the selected streams averages from about 0.15 to 2.27 cubic feet per square mile. The long-term gaged streamflow data indicate that the streamflow conditions for the period analyzed were in the 50- to 90-percent flow range, or in which streamflow would be exceeded about 50 to 90 percent of the time.
Gauging a Hydrocarbon Ruler by an Intrinsic Exciton Probe†
Khan, M. Adil; Neale, Chris; Michaux, Catherine; Pomés, Régis; Privé, Gilbert G.; Woody, Robert W.; Bishop, Russell E.
2016-01-01
The structural basis of lipid acyl-chain selection by membrane-intrinsic enzymes is poorly understood because most integral membrane enzymes of lipid metabolism have proven refractory to structure determination; however, robust enzymes from the outer membranes of Gram-negative bacteria are now providing a first glimpse at the underlying mechanisms. The methylene unit resolution of the phospholipid: lipid A palmitoyltransferase PagP is determined by the hydrocarbon ruler, a 16-carbon saturated acyl-chain-binding pocket buried within the transmembrane β-barrel structure. Substitution of Gly88 lining the floor of the hydrocarbon ruler with Ala or Met makes the enzyme select specifically 15- or 12-carbon saturated acyl chains, respectively, indicating that hydrocarbon ruler depth determines acyl-chain selection. However, the Gly88Cys PagP resolution does not diminish linearly because it selects both 14- and 15-carbon saturated acyl chains. We discovered that an exciton, emanating from a buried Tyr26–Trp66 phenol–indole interaction, is extinguished by a local structural perturbation arising from the proximal Gly88Cys PagP sulfhydryl group. Site-specific S-methylation of the single Cys afforded Gly88Cys-S-methyl PagP, which reasserted both the exciton and methylene unit resolution by specifically selecting 13-carbon saturated acyl chains for transfer to lipid A. Unlike the other Gly88 substitutions, the Cys sulfhydryl group recedes from the hydrocarbon ruler floor and locally perturbs the subjacent Tyr26 and Trp66 aromatic rings. The resulting hydrocarbon ruler expansion thus occurs at the exciton’s expense and accommodates an extra methylene unit in the selected acyl chain. The hydrocarbon ruler–exciton juxtaposition endows PagP with a molecular gauge for probing the structural basis of lipid acyl-chain selection in a membrane-intrinsic environment. PMID:17375935
Filtration of water-sediment samples for the determination of organic compounds
Sandstrom, Mark W.
1995-01-01
This report describes the equipment and procedures used for on-site filtration of surface-water and ground-water samples for determination of organic compounds. Glass-fiber filters and a positive displacement pumping system are suitable for processing most samples for organic analyses. An optional system that uses disposable in-line membrane filters is suitable for a specific gas chromatography/mass spectrometry, selected-ion monitoring analytical method for determination of organonitrogen herbicides. General procedures to minimize contamination of the samples include preparing a clean workspace at the site, selecting appropriate sample-collection materials, and cleaning of the equipment with detergent, tap water, and methanol.
Medvedovici, Andrei; Albu, Florin; Farca, Alexandru; David, Victor
2004-01-27
A new method for the determination of 2-[(dimethylamino)methyl]cyclohexanone (DAMC) in Tramadol (as active substance or active ingredient in pharmaceutical formulations) is described. The method is based on the derivatisation of 2-[(dimethylamino)methyl]cyclohexanone with 2,4-dinitrophenylhydrazine (2,4-DNPH) in acidic conditions followed by a reversed-phase liquid chromatographic separation with UV detection. The method is simple, selective, quantitative and allows the determination of 2-[(dimethylamino)methyl]cyclohexanone at the low ppm level. The proposed method was validated with respect to selectivity, precision, linearity, accuracy and robustness.
Ribot, C; Dutau, G; Manelfe, C; Bouissou, H; Rochiccioli, P
1977-02-01
A parathyroid adenoma is reported in a girl aged 12 years in whom hypercalcaemia was discovered by chance. Investigation of calcium metabolism suggested the diagnosis of hyperparathyroidism and studies of the urinary cyclic AMP and determination of the plasma parathyroid hormone concentration further added to the evidence. The diagnosis of parathyroid adenoma was made after determination of the parathyroid hormone concentration at various sights during selective catheterization of the tyroid veins. This was confirmed at surgery. In this patient the place of catheterization of the inferior thyroid veins in the early diagnosis of primary hyperparathyroidism is discussed.
Kazmier, Kelli; Alexander, Nathan S.; Meiler, Jens; Mchaourab, Hassane S.
2010-01-01
A hybrid protein structure determination approach combining sparse Electron Paramagnetic Resonance (EPR) distance restraints and Rosetta de novo protein folding has been previously demonstrated to yield high quality models (Alexander et al., 2008). However, widespread application of this methodology to proteins of unknown structures is hindered by the lack of a general strategy to place spin label pairs in the primary sequence. In this work, we report the development of an algorithm that optimally selects spin labeling positions for the purpose of distance measurements by EPR. For the α-helical subdomain of T4 lysozyme (T4L), simulated restraints that maximize sequence separation between the two spin labels while simultaneously ensuring pairwise connectivity of secondary structure elements yielded vastly improved models by Rosetta folding. 50% of all these models have the correct fold compared to only 21% and 8% correctly folded models when randomly placed restraints or no restraints are used, respectively. Moreover, the improvements in model quality require a limited number of optimized restraints, the number of which is determined by the pairwise connectivities of T4L α-helices. The predicted improvement in Rosetta model quality was verified by experimental determination of distances between spin labels pairs selected by the algorithm. Overall, our results reinforce the rationale for the combined use of sparse EPR distance restraints and de novo folding. By alleviating the experimental bottleneck associated with restraint selection, this algorithm sets the stage for extending computational structure determination to larger, traditionally elusive protein topologies of critical structural and biochemical importance. PMID:21074624
Selective complexation of K+ and Na+ in simple polarizable ion-ligating systems.
Bostick, David L; Brooks, Charles L
2010-09-29
An influx of experimental and theoretical studies of ion transport protein structure has inspired efforts to understand underlying determinants of ionic selectivity. Design principles for selective ion binding can be effectively isolated and interrogated using simplified models composed of a single ion surrounded by a set of ion-ligating molecular species. While quantum mechanical treatments of such systems naturally incorporate electronic degrees of freedom, their computational overhead typically prohibits thorough dynamic sampling of configurational space and, thus, requires approximations when determining ion-selective free energy. As an alternative, we employ dynamical simulations with a polarizable force field to probe the structure and K(+)/Na(+) selectivity in simple models composed of one central K(+)/Na(+) ion surrounded by 0-8 identical model compounds: N-methylacetamide, formamide, or water. In the absence of external restraints, these models represent gas-phase clusters displaying relaxed coordination structures with low coordination number. Such systems display Na(+) selectivity when composed of more than ∼3 organic carbonyl-containing compounds and always display K(+) selectivity when composed of water molecules. Upon imposing restraints that solely enforce specific coordination numbers, we find all models are K(+)-selective when ∼7-8-fold ion coordination is achieved. However, when models composed of the organic compounds provide ∼4-6-fold coordination, they retain their Na(+) selectivity. From these trends, design principles emerge that are of basic importance in the behavior of K(+) channel selectivity filters and suggest a basis not only for K(+) selectivity but also for modulation of block and closure by smaller ions.
Methods, media, and systems for detecting attack on a digital processing device
Stolfo, Salvatore J.; Li, Wei-Jen; Keromylis, Angelos D.; Androulaki, Elli
2014-07-22
Methods, media, and systems for detecting attack are provided. In some embodiments, the methods include: comparing at least part of a document to a static detection model; determining whether attacking code is included in the document based on the comparison of the document to the static detection model; executing at least part of the document; determining whether attacking code is included in the document based on the execution of the at least part of the document; and if attacking code is determined to be included in the document based on at least one of the comparison of the document to the static detection model and the execution of the at least part of the document, reporting the presence of an attack. In some embodiments, the methods include: selecting a data segment in at least one portion of an electronic document; determining whether the arbitrarily selected data segment can be altered without causing the electronic document to result in an error when processed by a corresponding program; in response to determining that the arbitrarily selected data segment can be altered, arbitrarily altering the data segment in the at least one portion of the electronic document to produce an altered electronic document; and determining whether the corresponding program produces an error state when the altered electronic document is processed by the corresponding program.
Methods, media, and systems for detecting attack on a digital processing device
DOE Office of Scientific and Technical Information (OSTI.GOV)
Stolfo, Salvatore J.; Li, Wei-Jen; Keromytis, Angelos D.
Methods, media, and systems for detecting attack are provided. In some embodiments, the methods include: comparing at least part of a document to a static detection model; determining whether attacking code is included in the document based on the comparison of the document to the static detection model; executing at least part of the document; determining whether attacking code is included in the document based on the execution of the at least part of the document; and if attacking code is determined to be included in the document based on at least one of the comparison of the document tomore » the static detection model and the execution of the at least part of the document, reporting the presence of an attack. In some embodiments, the methods include: selecting a data segment in at least one portion of an electronic document; determining whether the arbitrarily selected data segment can be altered without causing the electronic document to result in an error when processed by a corresponding program; in response to determining that the arbitrarily selected data segment can be altered, arbitrarily altering the data segment in the at least one portion of the electronic document to produce an altered electronic document; and determining whether the corresponding program produces an error state when the altered electronic document is processed by the corresponding program.« less
Decision Variants for the Automatic Determination of Optimal Feature Subset in RF-RFE.
Chen, Qi; Meng, Zhaopeng; Liu, Xinyi; Jin, Qianguo; Su, Ran
2018-06-15
Feature selection, which identifies a set of most informative features from the original feature space, has been widely used to simplify the predictor. Recursive feature elimination (RFE), as one of the most popular feature selection approaches, is effective in data dimension reduction and efficiency increase. A ranking of features, as well as candidate subsets with the corresponding accuracy, is produced through RFE. The subset with highest accuracy (HA) or a preset number of features (PreNum) are often used as the final subset. However, this may lead to a large number of features being selected, or if there is no prior knowledge about this preset number, it is often ambiguous and subjective regarding final subset selection. A proper decision variant is in high demand to automatically determine the optimal subset. In this study, we conduct pioneering work to explore the decision variant after obtaining a list of candidate subsets from RFE. We provide a detailed analysis and comparison of several decision variants to automatically select the optimal feature subset. Random forest (RF)-recursive feature elimination (RF-RFE) algorithm and a voting strategy are introduced. We validated the variants on two totally different molecular biology datasets, one for a toxicogenomic study and the other one for protein sequence analysis. The study provides an automated way to determine the optimal feature subset when using RF-RFE.
Savithra, Prakash; Nagesh, Lakshminarayan Shetty
2013-01-01
To assess a) whether the quality of reporting of randomised controlled trials (RCTs) has improved since the formulation of the Consolidated Standards of Reporting Trials (CONSORT) statement and b) whether there is any difference in reporting of RCTs between the selected public health dentistry journals. A hand search of the journals of public health dentistry was performed and four journals were identified for the study. They were Community Dentistry and Oral Epidemiology (CDOE), Community Dental Health (CDH), Journal of Public Health Dentistry (JPHD) and Oral Health and Preventive Dentistry (OHPD). A total of 114 RCTs published between 1990 and 2009 were selected. CONSORT guidelines were applied to each selected article in order to assess and determine any improvement since the publication of CONSORT guidelines. The chi-square test was employed to determine any statistical significant difference in quality of reporting of RCTs before and after the publication of the CONSORT guidelines. A comparison was also done to determine any statistically significant difference in quality of reporting of RCTs between the selected journals. Title, abstract, discussion and conclusion sections of the selected articles showed adherence to the CONSORT guidelines, whereas the compliance was poor with respect to the methodology section. The quality of reporting of RCTs is generally poor in public health dentistry journals. Overall, the quality of reporting has not substantially improved since the publication of CONSORT guidelines.
Riley, Sean P; Covington, Kyle; Landry, Michel D; McCallum, Christine; Engelhard, Chalee; Cook, Chad E
2016-01-01
This study aimed to compare selectivity characteristics among institution characteristics to determine differences by institutional funding source (public vs. private) or research activity level (research vs. non-research). This study included information provided by the Commission on Accreditation in Physical Therapy Education (CAPTE) and the Federation of State Boards of Physical Therapy. Data were extracted from all students who graduated in 2011 from accredited physical therapy programs in the United States. The public and private designations of the institutions were extracted directly from the classifications from the 'CAPTE annual accreditation report,' and high and low research activity was determined based on Carnegie classifications. The institutions were classified into four groups: public/research intensive, public/non-research intensive, private/research intensive, and private/non-research intensive. Descriptive and comparison analyses with post hoc testing were performed to determine whether there were statistically significant differences among the four groups. Although there were statistically significant baseline grade point average differences among the four categorized groups, there were no significant differences in licensure pass rates or for any of the selectivity variables of interest. Selectivity characteristics did not differ by institutional funding source (public vs. private) or research activity level (research vs. non-research). This suggests that the concerns about reduced selectivity among physiotherapy programs, specifically the types that are experiencing the largest proliferation, appear less warranted.
Sex ratio selection and multi-factorial sex determination in the housefly: a dynamic model.
Kozielska, M; Pen, I; Beukeboom, L W; Weissing, F J
2006-05-01
Sex determining (SD) mechanisms are highly variable between different taxonomic groups and appear to change relatively quickly during evolution. Sex ratio selection could be a dominant force causing such changes. We investigate theoretically the effect of sex ratio selection on the dynamics of a multi-factorial SD system. The system considered resembles the naturally occurring three-locus system of the housefly, which allows for male heterogamety, female heterogamety and a variety of other mechanisms. Sex ratio selection is modelled by assuming cost differences in the production of sons and daughters, a scenario leading to a strong sex ratio bias in the absence of constraints imposed by the mechanism of sex determination. We show that, despite of the presumed flexibility of the SD system considered, equilibrium sex ratios never deviate strongly from 1 : 1. Even if daughters are very costly, a male-biased sex ratio can never evolve. If sons are more costly, sex ratio can be slightly female biased but even in case of large cost differences the bias is very small (<10% from 1 : 1). Sex ratio selection can lead to a shift in the SD mechanism, but cannot be the sole cause of complete switches from one SD system to another. In fact, more than one locus remains polymorphic at equilibrium. We discuss our results in the context of evolution of the variable SD mechanism found in natural housefly populations.
Alpha-beta coordination method for collective search
Goldsmith, Steven Y.
2002-01-01
The present invention comprises a decentralized coordination strategy called alpha-beta coordination. The alpha-beta coordination strategy is a family of collective search methods that allow teams of communicating agents to implicitly coordinate their search activities through a division of labor based on self-selected roles and self-determined status. An agent can play one of two complementary roles. An agent in the alpha role is motivated to improve its status by exploring new regions of the search space. An agent in the beta role is also motivated to improve its status, but is conservative and tends to remain aggregated with other agents until alpha agents have clearly identified and communicated better regions of the search space. An agent can select its role dynamically based on its current status value relative to the status values of neighboring team members. Status can be determined by a function of the agent's sensor readings, and can generally be a measurement of source intensity at the agent's current location. An agent's decision cycle can comprise three sequential decision rules: (1) selection of a current role based on the evaluation of the current status data, (2) selection of a specific subset of the current data, and (3) determination of the next heading using the selected data. Variations of the decision rules produce different versions of alpha and beta behaviors that lead to different collective behavior properties.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Pryfogle, Peter Albert
2000-09-01
For the past three years, scientists at the Idaho National Engineering and Environmental Laboratory have been conducting studies aimed at determining the presence and influence of bacteria found in geothermal plant cooling water systems. In particular, the efforts have been directed at understanding the conditions that lead to the growth and accumulation of biomass within these systems, reducing the operational and thermal efficiency. Initially, the methods selected were based upon the current practices used by the industry and included the collection of water quality parameters, the measurement of soluble carbon, and the use of selective medial for the determination ofmore » the number density of various types of organisms. This data has been collected on a seasonal basis at six different facilities located at the Geysers’ in Northern California. While this data is valuable in establishing biological growth trends in the facilities and providing an initial determination of upset or off-normal conditions, more detailed information about the biological activity is needed to determine what is triggering or sustaining the growth in these facilities in order to develop improved monitoring and treatment techniques. In recent years, new biochemical approaches, based upon the analyses of phospholipid fatty acids and DNA recovered from environmental samples, have been developed and commercialized. These techniques, in addition to allowing the determination of the quantity of biomass, also provide information on the community composition and the nutritional status of the organisms. During the past year, samples collected from the condenser effluents of four of the plants from The Geysers’ were analyzed using these methods and compared with the results obtained from selective culturing techniques. The purpose of this effort was to evaluate the cost-benefit of implementing these techniques for tracking microbial activity in the plant study, in place of the selective culturing analyses that are currently the industry standard.« less
Yan, Hongyuan; Wang, Fang; Han, Dandan; Yang, Gengliang
2012-06-21
A highly selective molecularly imprinted solid-phase extraction (MISPE) combined with liquid chromatography-ultraviolet detection was developed for the simultaneous isolation and determination of four plant hormones including indole-3-acetic acid (IAA), indole-3-propionic acid (IPA), indole-3-butyric acid (IBA) and 1-naphthaleneacetic acid (NAA) in banana samples. The new molecularly imprinted microspheres (MIMs) prepared by aqueous suspension polymerization using 3-hydroxy-2-naphthoic acid and 1-methylpiperazine as mimic templates performed with high selectivity and affinity for the four plant hormones, and applied as selective sorbents of solid-phase extraction could effectively eliminate the interferences of the banana matrix. Good linearity was obtained in a range of 0.04-4.00 μg g(-1) and the recoveries of the four plant hormones at three spiked levels ranged from 78.5 to 107.7% with the relative standard deviations (RSD) of less than 4.6%. The developed MISPE-HPLC protocol obviously improved the selectivity and eliminated the effect of template leakage on quantitative analysis, and could be applied for the determination of plant hormones in complicated biological samples.
Yan, Hongyuan; Qiao, Jindong; Pei, Yuning; Long, Tao; Ding, Wen; Xie, Kun
2012-05-01
New molecularly imprinted microspheres synthesized by suspension polymerisation using phenylamine and naphthol as mimic template were successfully applied as selective sorbents for the solid-phase extraction used for the simultaneous determination of four Sudan dyes from preserved beancurd products. The obtained imprinted microspheres showed good recognition and selectivity to the four Sudan dyes in aqueous solution and the affinity could be easily controlled by adjusting the property of the solution. Under the selected experimental condition, the recoveries of the Sudan dyes in preserved beancurds at three spiked levels were ranged between 90.2-104.5% with the relative standard deviation of less than 6.8%. The limit of detection (LOD) and limit of quantification (LOQ) based on a signal-to-noise of 3 and 10 were in the range of 0.005-0.009μgg(-1) and 0.015-0.030μgg(-1), respectively. Comparing with alumina and C18-based extraction, the selectivity and repeatability of molecularly imprinted solid-phase extraction (MISPE) were obviously improved. This method could be potentially applied for the determination of Sudan dyes in complicated food samples. Copyright © 2011 Elsevier Ltd. All rights reserved.
Selection of staphylococcal enterotoxin B (SEB)-binding peptide using phage display technology
DOE Office of Scientific and Technical Information (OSTI.GOV)
Soykut, Esra Acar; Dudak, Fahriye Ceyda; Boyaci, Ismail Hakki
In this study, peptides were selected to recognize staphylococcal enterotoxin B (SEB) which cause food intoxication and can be used as a biological war agent. By using commercial M13 phage library, single plaque isolation of 38 phages was done and binding affinities were investigated with phage-ELISA. The specificities of the selected phage clones showing high affinity to SEB were checked by using different protein molecules which can be found in food samples. Furthermore, the affinities of three selected phage clones were determined by using surface plasmon resonance (SPR) sensors. Sequence analysis was realized for three peptides showing high binding affinitymore » to SEB and WWRPLTPESPPA, MNLHDYHRLFWY, and QHPQINQTLYRM amino acid sequences were obtained. The peptide sequence with highest affinity to SEB was synthesized with solid phase peptide synthesis technique and thermodynamic constants of the peptide-SEB interaction were determined by using isothermal titration calorimetry (ITC) and compared with those of antibody-SEB interaction. The binding constant of the peptide was determined as 4.2 {+-} 0.7 x 10{sup 5} M{sup -1} which indicates a strong binding close to that of antibody.« less
Determination of Azimuth Angle at Burnout for Placing a Satellite Over a Selected Earth Position
NASA Technical Reports Server (NTRS)
Skopinski, T. H.; Johnson, Katherine G.
1960-01-01
Expressions are presented for relating the satellite position in the orbital plane with the projected latitude and longitude on a rotating earth surface. An expression is also presented for determining the azimuth angle at a given burnout position on the basis of a selected passage position on the earth's surface. Examples are presented of a satellite launched eastward and one launched westward, each passing over a selected position sometime after having completed three orbits. Incremental changes from the desired latitude and longitude due to the earth's oblateness are included in the iteration for obtaining the azimuth angles of the two examples. The results for both cases are then compared with those obtained from a computing program using an oblate rotating earth. Changes from the selected latitude and longitude resulting from incremental changes from the burn-out azimuth angle and latitude are also analyzed.
NASA Technical Reports Server (NTRS)
Lange, R.; Savage, M.; Peyton, B.
1981-01-01
The performance of a dual-channel infrared heterodyne radiometer, designed to remotely monitor the concentration and vertical distribution of selected atmospheric species, is described. Ground based solar viewing measurement using the IHR were performed at selected laser transitions for ammonia (NH3 and ozone O3). Flight tests were conducted aboard the Galileo II, NASA Ames CV-990, on the Latitude Survey Mission. Ozone was the selected atmospheric species for the airborne flight measurements because of the scientific interest in this atmospheric species, the availability of in situ monitors, the coordinated ozone measurements, and the availability of ground truth data. The IHS was operated in the solar viewing mode to determine ozone distributions in the stratosphere and in the nadir viewing mode to determine the ozone distribution in the troposphere. Airborne atmospheric propagation measurements also were carried out at selected CO2 laser transitions.
NASA Technical Reports Server (NTRS)
Hidalgo, Homero, Jr.
2000-01-01
An innovative methodology for determining structural target mode selection and mode selection based on a specific criterion is presented. An effective approach to single out modes which interact with specific locations on a structure has been developed for the X-33 Launch Vehicle Finite Element Model (FEM). We presented Root-Sum-Square (RSS) displacement method computes resultant modal displacement for each mode at selected degrees of freedom (DOF) and sorts to locate modes with highest values. This method was used to determine modes, which most influenced specific locations/points on the X-33 flight vehicle such as avionics control components, aero-surface control actuators, propellant valve and engine points for use in flight control stability analysis and for flight POGO stability analysis. Additionally, the modal RSS method allows for primary or global target vehicle modes to also be identified in an accurate and efficient manner.
High Accuracy Fuel Flowmeter, Phase 1
NASA Technical Reports Server (NTRS)
Mayer, C.; Rose, L.; Chan, A.; Chin, B.; Gregory, W.
1983-01-01
Technology related to aircraft fuel mass - flowmeters was reviewed to determine what flowmeter types could provide 0.25%-of-point accuracy over a 50 to one range in flowrates. Three types were selected and were further analyzed to determine what problem areas prevented them from meeting the high accuracy requirement, and what the further development needs were for each. A dual-turbine volumetric flowmeter with densi-viscometer and microprocessor compensation was selected for its relative simplicity and fast response time. An angular momentum type with a motor-driven, spring-restrained turbine and viscosity shroud was selected for its direct mass-flow output. This concept also employed a turbine for fast response and a microcomputer for accurate viscosity compensation. The third concept employed a vortex precession volumetric flowmeter and was selected for its unobtrusive design. Like the turbine flowmeter, it uses a densi-viscometer and microprocessor for density correction and accurate viscosity compensation.
Mueller, David S.
2013-01-01
profiles from the entire cross section and multiple transects to determine a mean profile for the measurement. The use of an exponent derived from normalized data from the entire cross section is shown to be valid for application of the power velocity distribution law in the computation of the unmeasured discharge in a cross section. Selected statistics are combined with empirically derived criteria to automatically select the appropriate extrapolation methods. A graphical user interface (GUI) provides the user tools to visually evaluate the automatically selected extrapolation methods and manually change them, as necessary. The sensitivity of the total discharge to available extrapolation methods is presented in the GUI. Use of extrap by field hydrographers has demonstrated that extrap is a more accurate and efficient method of determining the appropriate extrapolation methods compared with tools currently (2012) provided in the ADCP manufacturers’ software.
Scale-Dependent Habitat Selection and Size-Based Dominance in Adult Male American Alligators
Strickland, Bradley A.; Vilella, Francisco J.; Belant, Jerrold L.
2016-01-01
Habitat selection is an active behavioral process that may vary across spatial and temporal scales. Animals choose an area of primary utilization (i.e., home range) then make decisions focused on resource needs within patches. Dominance may affect the spatial distribution of conspecifics and concomitant habitat selection. Size-dependent social dominance hierarchies have been documented in captive alligators, but evidence is lacking from wild populations. We studied habitat selection for adult male American alligators (Alligator mississippiensis; n = 17) on the Pearl River in central Mississippi, USA, to test whether habitat selection was scale-dependent and individual resource selectivity was a function of conspecific body size. We used K-select analysis to quantify selection at the home range scale and patches within the home range to determine selection congruency and important habitat variables. In addition, we used linear models to determine if body size was related to selection patterns and strengths. Our results indicated habitat selection of adult male alligators was a scale-dependent process. Alligators demonstrated greater overall selection for habitat variables at the patch level and less at the home range level, suggesting resources may not be limited when selecting a home range for animals in our study area. Further, diurnal habitat selection patterns may depend on thermoregulatory needs. There was no relationship between resource selection or home range size and body size, suggesting size-dependent dominance hierarchies may not have influenced alligator resource selection or space use in our sample. Though apparent habitat suitability and low alligator density did not manifest in an observed dominance hierarchy, we hypothesize that a change in either could increase intraspecific interactions, facilitating a dominance hierarchy. Due to the broad and diverse ecological roles of alligators, understanding the factors that influence their social dominance and space use can provide great insight into their functional role in the ecosystem. PMID:27588947
Scale-dependent habitat selection and size-based dominance in adult male American alligators
Strickland, Bradley A.; Vilella, Francisco; Belant, Jerrold L.
2016-01-01
Habitat selection is an active behavioral process that may vary across spatial and temporal scales. Animals choose an area of primary utilization (i.e., home range) then make decisions focused on resource needs within patches. Dominance may affect the spatial distribution of conspecifics and concomitant habitat selection. Size-dependent social dominance hierarchies have been documented in captive alligators, but evidence is lacking from wild populations. We studied habitat selection for adult male American alligators (Alligator mississippiensis; n = 17) on the Pearl River in central Mississippi, USA, to test whether habitat selection was scale-dependent and individual resource selectivity was a function of conspecific body size. We used K-select analysis to quantify selection at the home range scale and patches within the home range to determine selection congruency and important habitat variables. In addition, we used linear models to determine if body size was related to selection patterns and strengths. Our results indicated habitat selection of adult male alligators was a scale-dependent process. Alligators demonstrated greater overall selection for habitat variables at the patch level and less at the home range level, suggesting resources may not be limited when selecting a home range for animals in our study area. Further, diurnal habitat selection patterns may depend on thermoregulatory needs. There was no relationship between resource selection or home range size and body size, suggesting size-dependent dominance hierarchies may not have influenced alligator resource selection or space use in our sample. Though apparent habitat suitability and low alligator density did not manifest in an observed dominance hierarchy, we hypothesize that a change in either could increase intraspecific interactions, facilitating a dominance hierarchy. Due to the broad and diverse ecological roles of alligators, understanding the factors that influence their social dominance and space use can provide great insight into their functional role in the ecosystem.
Srinivas, Nuggehally R
2006-05-01
The development of sound bioanalytical method(s) is of paramount importance during the process of drug discovery and development culminating in a marketing approval. Although the bioanalytical procedure(s) originally developed during the discovery stage may not necessarily be fit to support the drug development scenario, they may be suitably modified and validated, as deemed necessary. Several reviews have appeared over the years describing analytical approaches including various techniques, detection systems, automation tools that are available for an effective separation, enhanced selectivity and sensitivity for quantitation of many analytes. The intention of this review is to cover various key areas where analytical method development becomes necessary during different stages of drug discovery research and development process. The key areas covered in this article with relevant case studies include: (a) simultaneous assay for parent compound and metabolites that are purported to display pharmacological activity; (b) bioanalytical procedures for determination of multiple drugs in combating a disease; (c) analytical measurement of chirality aspects in the pharmacokinetics, metabolism and biotransformation investigations; (d) drug monitoring for therapeutic benefits and/or occupational hazard; (e) analysis of drugs from complex and/or less frequently used matrices; (f) analytical determination during in vitro experiments (metabolism and permeability related) and in situ intestinal perfusion experiments; (g) determination of a major metabolite as a surrogate for the parent molecule; (h) analytical approaches for universal determination of CYP450 probe substrates and metabolites; (i) analytical applicability to prodrug evaluations-simultaneous determination of prodrug, parent and metabolites; (j) quantitative determination of parent compound and/or phase II metabolite(s) via direct or indirect approaches; (k) applicability in analysis of multiple compounds in select disease areas and/or in clinically important drug-drug interaction studies. A tabular representation of select examples of analysis is provided covering areas of separation conditions, validation aspects and applicable conclusion. A limited discussion is provided on relevant aspects of the need for developing bioanalytical procedures for speedy drug discovery and development. Additionally, some key elements such as internal standard selection, likely issues of mass detection, matrix effect, chiral aspects etc. are provided for consideration during method development.
Zhang, Zhuomin; Ma, Yunjian; Wang, Qingtang; Chen, An; Pan, Zhuoyan; Li, Gongke
2013-05-17
A novel alumina nanowire (ANW) solid-phase microextraction (SPME) fiber coating was prepared by a simple and rapid anodization-chemical etching method for ultra-selective determination of volatile esters and alcohols from complicated food samples. Preparation conditions for ANW SPME fiber coating including corrosion solution concentration and corrosion time were optimized in detail for better surface morphology and higher surface area based on scanning electron microscope (SEM). Under the optimum conditions, homogeneous alumina nanowire structure of ANW SPME fiber coating was achieved with the average thickness of 20 μm around. Compared with most of commercial SPME fiber coatings, ANW SPME fiber coatings achieved the higher extraction capacity and special selectivity for volatile esters and alcohols. Finally, an efficient gas sampling technique based on ANW SPME fiber coating as the core was established and successfully applied for the ultra-selective determination of trace volatile esters and alcohols from complicated banana and fermented glutinous rice samples coupled with gas chromatography/mass spectrometry (GC/MS) detection. It was interesting that 25 esters and 2 alcohols among 30 banana volatile organic compounds (VOCs) identified and 4 esters and 7 alcohols among 13 identified VOCs of fermented glutinous rice were selectively sampled by ANW SPME fiber coatings. Furthermore, new analytical methods for the determination of some typical volatile esters and alcohols from banana and fermented glutinous rice samples at specific storage or brewing phases were developed and validated. Good recoveries for banana and fermented glutinous rice samples were achieved in range of 108-115% with relative standard deviations (RSDs) of 2.6-6.7% and 80.0-91.8% with RSDs of 0.3-1.3% (n=3), respectively. This work proposed a novel and efficient gas sampling technique of ANW SPME which was quite suitable for ultra-selectively sampling trace volatile esters and alcohols from complicated food samples. Copyright © 2013 Elsevier B.V. All rights reserved.
ERIC Educational Resources Information Center
Hughes, Carolyn; Cosgriff, Joseph C.; Agran, Martin; Washington, Barbara H.
2013-01-01
Little is known about the effects of participation in inclusive settings on student self-determination. In this exploratory study, we examined the association between students' inclusive school and community activities and the self-determination skills of active involvement in IEP activities and use of selected self-determination strategies.…
Daquigan, Ninalynn; Grim, Christopher J; White, James R; Hanes, Darcy E; Jarvis, Karen G
2016-01-01
Culture based methods are commonly employed to detect pathogens in food and environmental samples. These methods are time consuming and complex, requiring multiple non-selective and selective enrichment broths, and usually take at least 1 week to recover and identify pathogens. Improving pathogen detection in foods is a primary goal for regulatory agencies and industry. Salmonella detection in food relies on a series of culture steps in broth formulations optimized to resuscitate Salmonella and reduce the abundance of competitive bacteria. Examples of non-selective pre-enrichment broths used to isolate Salmonella from food include Lactose, Universal Pre-enrichment, BPW, and Trypticase Soy broths. Tetrathionate (TT) and Rappaport-Vassiliadis (RV) broths are employed after a 24-h non-selective enrichment to select for Salmonella and hamper the growth of competitive bacteria. In this study, we tested a new formulation of TT broth that lacks brilliant green dye and has lower levels of TT . We employed this TT broth formulation in conjunction with a 6-h non-selective pre-enrichment period and determined that Salmonella recovery was possible one day earlier than standard food culture methods. We tested the shortened culture method in different non-selective enrichment broths, enumerated Salmonella in the non-selective enrichments, and used 16S rRNA gene sequencing to determine the proportional abundances of Salmonella in the TT and RV selective enrichments. Together these data revealed that a 6-h non-selective pre-enrichment reduces the levels of competitive bacteria inoculated into the selective TT and RV broths, enabling the recovery of Salmonella 1 day earlier than standard culture enrichment methods.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Muir, G.K.P., E-mail: Graham.Muir@glasgow.ac.uk; Hayward, S.; Tripney, B.G.
2015-01-15
Highlights: • Compares industry standard and {sup 14}C methods for determining bioenergy content of MSW. • Differences quantified through study at an operational energy from waste plant. • Manual sort and selective dissolution are unreliable measures of feedstock bioenergy. • {sup 14}C methods (esp. AMS) improve precision and reliability of bioenergy determination. • Implications for electricity generators and regulators for award of bio-incentives. - Abstract: {sup 14}C analysis of flue gas by accelerator mass spectrometry (AMS) and liquid scintillation counting (LSC) were used to determine the biomass fraction of mixed waste at an operational energy-from-waste (EfW) plant. Results were convertedmore » to bioenergy (% total) using mathematical algorithms and assessed against existing industry methodologies which involve manual sorting and selective dissolution (SD) of feedstock. Simultaneous determinations using flue gas showed excellent agreement: 44.8 ± 2.7% for AMS and 44.6 ± 12.3% for LSC. Comparable bioenergy results were obtained using a feedstock manual sort procedure (41.4%), whilst a procedure based on selective dissolution of representative waste material is reported as 75.5% (no errors quoted). {sup 14}C techniques present significant advantages in data acquisition, precision and reliability for both electricity generator and industry regulator.« less
Wickman, Jonas; Diehl, Sebastian; Blasius, Bernd; Klausmeier, Christopher A; Ryabov, Alexey B; Brännström, Åke
2017-04-01
Spatial structure can decisively influence the way evolutionary processes unfold. To date, several methods have been used to study evolution in spatial systems, including population genetics, quantitative genetics, moment-closure approximations, and individual-based models. Here we extend the study of spatial evolutionary dynamics to eco-evolutionary models based on reaction-diffusion equations and adaptive dynamics. Specifically, we derive expressions for the strength of directional and stabilizing/disruptive selection that apply both in continuous space and to metacommunities with symmetrical dispersal between patches. For directional selection on a quantitative trait, this yields a way to integrate local directional selection across space and determine whether the trait value will increase or decrease. The robustness of this prediction is validated against quantitative genetics. For stabilizing/disruptive selection, we show that spatial heterogeneity always contributes to disruptive selection and hence always promotes evolutionary branching. The expression for directional selection is numerically very efficient and hence lends itself to simulation studies of evolutionary community assembly. We illustrate the application and utility of the expressions for this purpose with two examples of the evolution of resource utilization. Finally, we outline the domain of applicability of reaction-diffusion equations as a modeling framework and discuss their limitations.
Elsayed, Sameer; Gregson, Daniel B; Church, Deirdre L
2003-06-01
Group B streptococcus (GBS) is the most common cause of early-onset neonatal sepsis in developed countries, and determination of the GBS colonization status in pregnant patients near term is essential for the provision of prophylactic measures to prevent early-onset disease. To determine if GBS recovery rates and/or result turnaround times for vaginal or combined vaginal/rectal swab specimens from pregnant patients near term are enhanced if swabs are inoculated initially onto selective versus nonselective agar media, in addition to the standard Centers for Disease Control and Prevention method. Prospective laboratory analysis. Urban health region/centralized diagnostic microbiology laboratory. Pregnant women presenting for routine obstetrical care and collection of vaginal or combined vaginal/rectal swab specimens for GBS testing at 35 to 37 weeks' gestation. Culture of specimens directly onto selective (5% sheep blood with colistin and nalidixic acid) or nonselective (5% sheep blood) agar media, in addition to LIM broth enrichment and terminal subculture. Group B streptococcus recovery rate and culture result turnaround time. A total of 639 specimens were tested, with 128 (20%) positive for GBS. Sixty-three isolates were recovered on direct agar media at 24 hours, of which 16 (12.5%) were isolated on selective plates only. An additional 38 isolates were recovered at 48 hours from direct plates. Twenty-seven (21.1%) isolates that failed to grow on direct plates were recovered from the LIM broth subculture only. Three (2.3%) isolates not recovered from LIM broths were detected at 48 hours on the direct selective (2 isolates) and nonselective (1 isolate) agar plates. A 24-hour result turnaround time was achieved for 63 (49.2%) and 47 (36.7%) of the 128 culture-positive specimens for direct selective and nonselective plates, respectively (chi2 = 76.63, P <.001). Use of direct selective agar media, in addition to LIM broth enrichment, for the determination of the GBS colonization status in pregnant patients near term results in decreased turnaround time for reporting positive results.
Zhao, Chengliang; Zhang, Nan; He, Weiyan; Li, Rui; Shi, Dan; Pang, Li; Dong, Ning; Xu, Hong; Ji, Honglei
2014-04-01
A sensitive and selective liquid chromatography tandem mass spectrometry was developed and validated for the simultaneous determination of three major lignans (podophyllotoxin, epipodophyllotoxin, and 4'-demethylpodophyllotoxin) in rat plasma using diphenhydramine as the internal standard. The analytes were detected using a triple quadrupole mass spectrometer that was equipped with an electrospray ionization source in the positive ion and selected reaction monitoring modes. The linearity of the calibration curve was good, with coefficients of determination (r(2) ) >0.9914 for all of the analytes. The developed method was successfully applied for the simultaneous determination of the three lignans in rat plasma following oral administration of Diphylleia sinensis extract to rats. Copyright © 2013 John Wiley & Sons, Ltd.
System and method for controlling power consumption in a computer system based on user satisfaction
Yang, Lei; Dick, Robert P; Chen, Xi; Memik, Gokhan; Dinda, Peter A; Shy, Alex; Ozisikyilmaz, Berkin; Mallik, Arindam; Choudhary, Alok
2014-04-22
Systems and methods for controlling power consumption in a computer system. For each of a plurality of interactive applications, the method changes a frequency at which a processor of the computer system runs, receives an indication of user satisfaction, determines a relationship between the changed frequency and the user satisfaction of the interactive application, and stores the determined relationship information. The determined relationship can distinguish between different users and different interactive applications. A frequency may be selected from the discrete frequencies at which the processor of the computer system runs based on the determined relationship information for a particular user and a particular interactive application running on the processor of the computer system. The processor may be adapted to run at the selected frequency.
1980-09-01
AFWAL-TR-80-41 16 a N0946 6 6 PORCELAIN ENAMEL MATERIAL TESTING PROCEDURES TO DETERMINE THE DAMPINGi l PROPERTIES AND THE RESULTS OF ,= SELECTED...15..DECLASSI FtCATION/ DOWNGRADING SCHEDULE N.A(U~~~~ ~N A. 7~ ~&:’? 16 . DISThmBUTTUSTATEMENT (o1 this Report) Approved for public release...Damping Fixture 15 Number One 6 High Temperature Enamels Damping Fixture 16 Number Two 7 Schematic of the Enamels Testing Furnace Showing 18 the
Solute-Gas Equilibria in Multi-Organic Aqueous Systems
1981-11-30
THIS PAGK(*7@nDae~ Kht.Eero*g) Block 20 (cont.) --z Henry’s constants for selected organic solvents were determined at ionic strengths up to 1.0 M (KC1...equili- brium, batch stripping reactor. Data were fit to a regression equation. Henry’s constants for selected organic solvents were determined at ionic...organic systems. The presence of additional or- ganics (some perhaps not even strippable ) likely to be found along with a particular volatile should be
May, Thomas W.; Walther, Mike W.; Brumbaugh, William G.
2007-01-01
This report presents raw data on selenium concentrations in samples of water, sediment, detritus, and selected food-chain matrices collected from selected agricultural drains in the southern portion of the Salton Sea during October 2006 and January 2007. Total selenium and selenium species were determined in water samples, whereas total selenium was determined in sediment, detritus, algae, plankton, midge larvae (Family Chironomidae), and two fish species (western mosquitofish, Gambusia affinis, and sailfin molly, Poecilia latipinna).
Space simulation test for thermal control materials
NASA Technical Reports Server (NTRS)
Hardgrove, W. R.
1990-01-01
Tests were run in TRW's Combined Environment Facility to examine the degradation of thermal control materials in a simulated space environment. Thermal control materials selected for the test were those presently being used on spacecraft or predicted to be used within the next few years. The geosynchronous orbit environment was selected as the most interesting. One of the goals was to match degradation of those materials with available flight data. Another aim was to determine if degradation can adequately be determined with accelerated or short term ground tests.
Corn blight review: Sampling model and ground data measurements program
NASA Technical Reports Server (NTRS)
Allen, R. D.
1972-01-01
The sampling plan involved the selection of the study area, determination of the flightline and segment sample design within the study area, and determination of a field sample design. Initial interview survey data consisting of crop species acreage and land use were collected. On all corn fields, additional information such as seed type, row direction, population, planting date, ect. were also collected. From this information, sample corn fields were selected to be observed through the growing season on a biweekly basis by county extension personnel.
1984-09-01
is not only difficult and time consuming , but also crucial to the success of the project, the question is whether a decision support system designed...KtI I - uAujvhIMtf IENE In THE FEASIBILITY OF A DECISION SUPPORT SYSTEM FOR THE DETERMINATION OF SOURCE SELECTION EVALUATION ’CRITERIA THESIS .2...INSTITUTE OF TECHNOLOGY Wright-Patterson Air Force Base, Ohio DZM=0N STATEMENT A ,’r !’ILMILSHIM S /8 4 THE FEASIBILITY OF A DECISION SUPPORT SYSTEM FOR
Goetz, H; Kuschel, M; Wulff, T; Sauber, C; Miller, C; Fisher, S; Woodward, C
2004-09-30
Protein analysis techniques are developing fast due to the growing number of proteins obtained by recombinant DNA techniques. In the present paper we compare selected techniques, which are used for protein sizing, quantitation and molecular weight determination: sodium dodecylsulfate-polyacrylamide gel electrophoresis (SDS-PAGE), lab-on-a-chip or microfluidics technology (LoaC), size exclusion chromatography (SEC) and mass spectrometry (MS). We compare advantages and limitations of each technique in respect to different application areas, analysis time, protein sizing and quantitation performance.
Optimizing the availability of a buffered industrial process
Martz, Jr., Harry F.; Hamada, Michael S.; Koehler, Arthur J.; Berg, Eric C.
2004-08-24
A computer-implemented process determines optimum configuration parameters for a buffered industrial process. A population size is initialized by randomly selecting a first set of design and operation values associated with subsystems and buffers of the buffered industrial process to form a set of operating parameters for each member of the population. An availability discrete event simulation (ADES) is performed on each member of the population to determine the product-based availability of each member. A new population is formed having members with a second set of design and operation values related to the first set of design and operation values through a genetic algorithm and the product-based availability determined by the ADES. Subsequent population members are then determined by iterating the genetic algorithm with product-based availability determined by ADES to form improved design and operation values from which the configuration parameters are selected for the buffered industrial process.
Moghadam Zadeh, Hamid Reza; Ahmadvand, Parvaneh; Behbahani, Ali; Amini, Mostafa M; Sayar, Omid
2015-01-01
Graphene oxide nano-sheet was modified with dithizone as a novel sorbent for selective pre-concentration and determination of Cd(II) and Pb(II) in food. The sorbent was characterised by various analytical methods and the effective parameters for Cd(II) and Pb(II) adsorption were optimised during this work. The high adsorption capacity and selectivity of this sorbent makes the method capable of fast determinations of the Cd(II) and Pb(II) content in complicated matrices even at μg l(-1) levels using commonly available instrumentation. The precision of this method was < 1.9% from 10 duplicate determinations and its accuracy verified using standard reference materials. Finally, this method was applied to the determination of Cd(II) and Pb(II) ions in common food samples and satisfactory results were obtained.
Frag, Eman Y Z; Mohamed, Gehad G; Khalil, Mohamed M; Hwehy, Mohammad M A
2011-01-01
This study compares between unmodified carbon paste (CPE; the paste has no ion pair) and polyvinyl chloride (PVC) membrane selective electrodes that were used in potentiometric determination of ketotifen fumarate (KTF), where sodium tetraphenylborate (NaTPB) was used as titrant. The performance characteristics of these sensors were evaluated according to IUPAC recommendations which reveal a fast, stable, and linear response for KTF over the concentration range of 10(-7) to 10(-2) mol L(-1). The electrodes show Nernstian slope value of 52.51 ± 0.20 and 51.51 ± 0.25 mV decade(-1) for CPE and PVC membrane electrodes at 30°C, respectively. The potential is nearly stable over the pH range 3.0-6.0 and 2.0-7.0 for CPE and PVC membrane electrodes, respectively. Selectivity coefficient values towards different inorganic cations, sugars, and amino acids reflect high selectivity of the prepared electrodes. The electrodes responses at different temperatures were also studied, and long operational lifetime of 12 and 5 weeks for CPE and PVC membrane electrodes, respectively, were found. These are used for determination of ketotifen fumarate using potentiometric titration, calibration, and standard addition methods in pure samples, its pharmaceutical preparations (Zaditen tablets), and biological fluid (urine). The direct potentiometric determination of KTF using the proposed sensors gave recoveries % of 98.97 ± 0.53 and 98.62 ± 0.74 with RSD 1.42 and 0.63% for CPE and PVC membrane selective electrodes, respectively. Validation of the method shows suitability of the proposed sensors for use in quality control assessment of KTF. The obtained results were in a good agreement with those obtained using the reported spectrophotometric method.
Frag, Eman Y. Z.; Mohamed, Gehad G.; Khalil, Mohamed M.; Hwehy, Mohammad M. A.
2011-01-01
This study compares between unmodified carbon paste (CPE; the paste has no ion pair) and polyvinyl chloride (PVC) membrane selective electrodes that were used in potentiometric determination of ketotifen fumarate (KTF), where sodium tetraphenylborate (NaTPB) was used as titrant. The performance characteristics of these sensors were evaluated according to IUPAC recommendations which reveal a fast, stable, and linear response for KTF over the concentration range of 10−7 to 10−2 mol L−1. The electrodes show Nernstian slope value of 52.51 ± 0.20 and 51.51 ± 0.25 mV decade−1 for CPE and PVC membrane electrodes at 30°C, respectively. The potential is nearly stable over the pH range 3.0–6.0 and 2.0–7.0 for CPE and PVC membrane electrodes, respectively. Selectivity coefficient values towards different inorganic cations, sugars, and amino acids reflect high selectivity of the prepared electrodes. The electrodes responses at different temperatures were also studied, and long operational lifetime of 12 and 5 weeks for CPE and PVC membrane electrodes, respectively, were found. These are used for determination of ketotifen fumarate using potentiometric titration, calibration, and standard addition methods in pure samples, its pharmaceutical preparations (Zaditen tablets), and biological fluid (urine). The direct potentiometric determination of KTF using the proposed sensors gave recoveries % of 98.97 ± 0.53 and 98.62 ± 0.74 with RSD 1.42 and 0.63% for CPE and PVC membrane selective electrodes, respectively. Validation of the method shows suitability of the proposed sensors for use in quality control assessment of KTF. The obtained results were in a good agreement with those obtained using the reported spectrophotometric method. PMID:22013443
NASA Astrophysics Data System (ADS)
Wang, Wenlei; Wu, Xiaojie; Wang, Chao; Jia, Zhaojun; He, Linwen; Wei, Yifan; Niu, Jianfeng; Wang, Guangce
2014-07-01
To screen the stable expression genes related to the stress (strong light, dehydration and temperature shock) we applied Absolute real-time PCR technology to determine the transcription numbers of the selected test genes in P orphyra yezoensis, which has been regarded as a potential model species responding the stress conditions in the intertidal. Absolute real-time PCR technology was applied to determine the transcription numbers of the selected test genes in P orphyra yezoensis, which has been regarded as a potential model species in stress responding. According to the results of photosynthesis parameters, we observed that Y(II) and F v/ F m were significantly affected when stress was imposed on the thalli of P orphyra yezoensis, but underwent almost completely recovered under normal conditions, which were collected for the following experiments. Then three samples, which were treated with different grade stresses combined with salinity, irradiation and temperature, were collected. The transcription numbers of seven constitutive expression genes in above samples were determined after RNA extraction and cDNA synthesis. Finally, a general insight into the selection of internal control genes during stress response was obtained. We found that there were no obvious effects in terms of salinity stress (at salinity 90) on transcription of most genes used in the study. The 18S ribosomal RNA gene had the highest expression level, varying remarkably among different tested groups. RPS8 expression showed a high irregular variance between samples. GAPDH presented comparatively stable expression and could thus be selected as the internal control. EF-1α showed stable expression during the series of multiple-stress tests. Our research provided available references for the selection of internal control genes for transcripts determination of P. yezoensis.
Remy, Joan M; Tow-Keogh, Cheryl A; McConnell, Timothy S; Dalton, James M; Devito, Joseph A
2012-12-01
To determine the potential for delafloxacin to select for resistant mutants in methicillin-resistant Staphylococcus aureus (MRSA), including isolates with existing mutations in the quinolone resistance determining region (QRDR). Susceptibility testing by broth microdilution was performed on 30 MRSA clinical isolates. For four of these isolates, the presence or absence of mutations in the QRDR was characterized. Resistance selection was performed on these four isolates by spreading cells on drug-containing agar plates followed by incubation for 48 h. Resistance frequencies and mutant prevention concentrations (MPCs) were calculated for each; PCR amplification and sequencing were performed using standard methods to characterize mutations in the QRDR. Growth rate analysis was performed and relative fitness was determined. Delafloxacin demonstrated potent in vitro activity against this set of MRSA isolates, with MICs of 0.008-1 mg/L and an MIC(50) and MIC(90) of 0.03 and 0.5 mg/L, respectively. Spontaneous delafloxacin resistance frequencies for the MRSA strains were 2 × 10(-9) to <9.5 × 10(-11). Delafloxacin MPCs were one to four times the MIC for any isolate, lower than those of comparator quinolones. Some delafloxacin-selected mutants showed a fitness cost when co-cultured with the parent strain. Delafloxacin demonstrates excellent antibacterial potency and exhibits a low probability for the selection of resistant mutants in MRSA. Although mutants can be selected at low frequencies in vitro from quinolone-resistant isolates, delafloxacin MICs and MPCs remain low and a fitness cost can be observed. Consequently delafloxacin warrants further investigation for the potential treatment of drug-resistant MRSA infections.
Chen, Chung-De; Huang, Yen-Chieh; Chiang, Hsin-Lin; Hsieh, Yin-Cheng; Guan, Hong-Hsiang; Chuankhayan, Phimonphan; Chen, Chun-Jung
2014-09-01
Optimization of the initial phasing has been a decisive factor in the success of the subsequent electron-density modification, model building and structure determination of biological macromolecules using the single-wavelength anomalous dispersion (SAD) method. Two possible phase solutions (φ1 and φ2) generated from two symmetric phase triangles in the Harker construction for the SAD method cause the well known phase ambiguity. A novel direct phase-selection method utilizing the θ(DS) list as a criterion to select optimized phases φ(am) from φ1 or φ2 of a subset of reflections with a high percentage of correct phases to replace the corresponding initial SAD phases φ(SAD) has been developed. Based on this work, reflections with an angle θ(DS) in the range 35-145° are selected for an optimized improvement, where θ(DS) is the angle between the initial phase φ(SAD) and a preliminary density-modification (DM) phase φ(DM)(NHL). The results show that utilizing the additional direct phase-selection step prior to simple solvent flattening without phase combination using existing DM programs, such as RESOLVE or DM from CCP4, significantly improves the final phases in terms of increased correlation coefficients of electron-density maps and diminished mean phase errors. With the improved phases and density maps from the direct phase-selection method, the completeness of residues of protein molecules built with main chains and side chains is enhanced for efficient structure determination.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Deshpande, Amruta J.; Hughes, John P.; Wittman, David, E-mail: amrejd@physics.rutgers.edu, E-mail: jph@physics.rutgers.edu, E-mail: dwittman@physics.ucdavis.edu
We continue the study of the first sample of shear-selected clusters from the initial 8.6 square degrees of the Deep Lens Survey (DLS); a sample with well-defined selection criteria corresponding to the highest ranked shear peaks in the survey area. We aim to characterize the weak lensing selection by examining the sample’s X-ray properties. There are multiple X-ray clusters associated with nearly all the shear peaks: 14 X-ray clusters corresponding to seven DLS shear peaks. An additional three X-ray clusters cannot be definitively associated with shear peaks, mainly due to large positional offsets between the X-ray centroid and the shearmore » peak. Here we report on the XMM-Newton properties of the 17 X-ray clusters. The X-ray clusters display a wide range of luminosities and temperatures; the L {sub X} − T {sub X} relation we determine for the shear-associated X-ray clusters is consistent with X-ray cluster samples selected without regard to dynamical state, while it is inconsistent with self-similarity. For a subset of the sample, we measure X-ray masses using temperature as a proxy, and compare to weak lensing masses determined by the DLS team. The resulting mass comparison is consistent with equality. The X-ray and weak lensing masses show considerable intrinsic scatter (∼48%), which is consistent with X-ray selected samples when their X-ray and weak lensing masses are independently determined.« less
Code of Federal Regulations, 2013 CFR
2013-04-01
... 25 Indians 2 2013-04-01 2013-04-01 false How does the Director select which Tribes in the applicant pool become self-governance Tribes? 1000.27 Section 1000.27 Indians OFFICE OF THE ASSISTANT...-GOVERNMENT ACT AMENDMENTS TO THE INDIAN SELF-DETERMINATION AND EDUCATION ACT Selection of Additional Tribes...
Code of Federal Regulations, 2011 CFR
2011-04-01
... 25 Indians 2 2011-04-01 2011-04-01 false How does the Director select which Tribes in the applicant pool become self-governance Tribes? 1000.27 Section 1000.27 Indians OFFICE OF THE ASSISTANT...-GOVERNMENT ACT AMENDMENTS TO THE INDIAN SELF-DETERMINATION AND EDUCATION ACT Selection of Additional Tribes...
Code of Federal Regulations, 2010 CFR
2010-04-01
... 25 Indians 2 2010-04-01 2010-04-01 false How does the Director select which Tribes in the applicant pool become self-governance Tribes? 1000.27 Section 1000.27 Indians OFFICE OF THE ASSISTANT...-GOVERNMENT ACT AMENDMENTS TO THE INDIAN SELF-DETERMINATION AND EDUCATION ACT Selection of Additional Tribes...
Code of Federal Regulations, 2012 CFR
2012-04-01
... 25 Indians 2 2012-04-01 2012-04-01 false How does the Director select which Tribes in the applicant pool become self-governance Tribes? 1000.27 Section 1000.27 Indians OFFICE OF THE ASSISTANT...-GOVERNMENT ACT AMENDMENTS TO THE INDIAN SELF-DETERMINATION AND EDUCATION ACT Selection of Additional Tribes...
Code of Federal Regulations, 2014 CFR
2014-04-01
... 25 Indians 2 2014-04-01 2014-04-01 false How does the Director select which Tribes in the applicant pool become self-governance Tribes? 1000.27 Section 1000.27 Indians OFFICE OF THE ASSISTANT...-GOVERNMENT ACT AMENDMENTS TO THE INDIAN SELF-DETERMINATION AND EDUCATION ACT Selection of Additional Tribes...
USDA-ARS?s Scientific Manuscript database
The safety of weed biological control depends upon the selection and utilization of the target weed by the agent while causing minimal harm to non-target species. Selection of weed species by biological control agents is determined by the presence of behavioral cues, generally host secondary plant c...
J.Y.: Tan Zhu; K.L. Scallon; Y.L. Zhao; Y. Deng
2005-01-01
This study proposes a deinking selectivity concept that considers both ink removal and fiber yield in determining the performance of deinking operations. The defined deinking selectivity. or Z -factor, is expressed by the ratio of ink removal expressed by the International Standards Organization (ISO) brightness gain or the reduction in relative effective residual ink...
J.Y. Zhu; F. Tan; K.L. Scallon; Y. Zhao; Y. Deng
2004-01-01
Reducing fiber loss is also important to conserve resources and reduce the cost of secondary fibers. This study proposes a deinking selectivity concept that considers both ink removal and fiber yield in determining the performance of deinking operations. The defined deinking selectivity, or Z-factor, is expressed by the ratio of ink removal expressed by the...
A Study of Vocational Education as a Factor in Selecting a Community for a Manufacturing Plant Site.
ERIC Educational Resources Information Center
Dean, Ernest H.
The purpose of the study was to determine the factors considered by industrialists as they select communities in which to locate their new manufacturing plants, and to place the relative importance upon vocational-technical education as a factor in the plant site selection process. The three populations consisted of 113 companies of varying sizes…
ERIC Educational Resources Information Center
Regional Resource Center Program, 2014
2014-01-01
One component of the recently required State Systemic Improvement Plan (SSIP) for State Departments of Education calls for the selection and implementation of evidence-based practices (EBPs). This report provides six steps to guide the process of selecting evidence based practices (EBP): (1) Begin with the End in Mind--Determine Targeted Outcomes;…
Christine A. Costello; Mariko Yamasaki; Peter J. Pekins; William B. Leak; Christopher D. Neefus
2000-01-01
Clearcutting creates habitat for many species of early successional songbirds; however, little information is available on bird use of small forest openings created by group selection harvests. Group selection harvests are increasing on the White Mountain National Forest due to negative public response to clearcutting. The objective of this study was to determine if...
Payen, Celia; Di Rienzi, Sara C; Ong, Giang T; Pogachar, Jamie L; Sanchez, Joseph C; Sunshine, Anna B; Raghuraman, M K; Brewer, Bonita J; Dunham, Maitreya J
2014-03-20
Population adaptation to strong selection can occur through the sequential or parallel accumulation of competing beneficial mutations. The dynamics, diversity, and rate of fixation of beneficial mutations within and between populations are still poorly understood. To study how the mutational landscape varies across populations during adaptation, we performed experimental evolution on seven parallel populations of Saccharomyces cerevisiae continuously cultured in limiting sulfate medium. By combining quantitative polymerase chain reaction, array comparative genomic hybridization, restriction digestion and contour-clamped homogeneous electric field gel electrophoresis, and whole-genome sequencing, we followed the trajectory of evolution to determine the identity and fate of beneficial mutations. During a period of 200 generations, the yeast populations displayed parallel evolutionary dynamics that were driven by the coexistence of independent beneficial mutations. Selective amplifications rapidly evolved under this selection pressure, in particular common inverted amplifications containing the sulfate transporter gene SUL1. Compared with single clones, detailed analysis of the populations uncovers a greater complexity whereby multiple subpopulations arise and compete despite a strong selection. The most common evolutionary adaptation to strong selection in these populations grown in sulfate limitation is determined by clonal interference, with adaptive variants both persisting and replacing one another.
Payen, Celia; Di Rienzi, Sara C.; Ong, Giang T.; Pogachar, Jamie L.; Sanchez, Joseph C.; Sunshine, Anna B.; Raghuraman, M. K.; Brewer, Bonita J.; Dunham, Maitreya J.
2014-01-01
Population adaptation to strong selection can occur through the sequential or parallel accumulation of competing beneficial mutations. The dynamics, diversity, and rate of fixation of beneficial mutations within and between populations are still poorly understood. To study how the mutational landscape varies across populations during adaptation, we performed experimental evolution on seven parallel populations of Saccharomyces cerevisiae continuously cultured in limiting sulfate medium. By combining quantitative polymerase chain reaction, array comparative genomic hybridization, restriction digestion and contour-clamped homogeneous electric field gel electrophoresis, and whole-genome sequencing, we followed the trajectory of evolution to determine the identity and fate of beneficial mutations. During a period of 200 generations, the yeast populations displayed parallel evolutionary dynamics that were driven by the coexistence of independent beneficial mutations. Selective amplifications rapidly evolved under this selection pressure, in particular common inverted amplifications containing the sulfate transporter gene SUL1. Compared with single clones, detailed analysis of the populations uncovers a greater complexity whereby multiple subpopulations arise and compete despite a strong selection. The most common evolutionary adaptation to strong selection in these populations grown in sulfate limitation is determined by clonal interference, with adaptive variants both persisting and replacing one another. PMID:24368781
ERIC Educational Resources Information Center
Griswold, John R.; Rauner, Richard A.
1990-01-01
Presented are the procedures and a discussion of the results for an experiment in which students select unknown carboxylic acids, determine their melting points, and investigate their solubility behavior in water and ethanol. A table of selected carboxylic acids is included. (CW)
ANALYSIS OF SELECTED CHEMICAL GROUPS BY LIQUID CHROMATOGRAPHY/MASS SPECTROMETRY
The use of the moving-belt liquid chromatographic interface in combination with mass spectrometry was evaluated for determining detection limits of selected members of various chemical classes. mong the chemical classes examined were benzidines, nitrosoamines, anilines, nitroarom...
Application of Metal Catalysts for High Selectivity of Glycerol Conversion to Alcohols
DOT National Transportation Integrated Search
2010-11-01
The objective of this project is to determine the applicability of metal-based catalysts and optimize the process conditions for thermochemically producing primary alcohols. Metal catalysts were evaluated for their selectivities for producing alcohol...
Determination of Fluoride in Toothpaste Using an Ion-Selective Electrode
ERIC Educational Resources Information Center
Light, Truman S.; Cappuccino, Carleton C.
1975-01-01
Outlines the theory of chemical potentiometry, describes the experimental procedure for free fluoride determination, and presents sample data of fluoride concentration for various brands of toothpaste. (GS)
THE DERIVATION, ANALYSIS, AND CLASSIFICATION OF INSTRUCTIONAL OBJECTIVES.
ERIC Educational Resources Information Center
AMMERMAN, HARRY L.; MELCHING, WILLIAM H.
THIS REPORT EXAMINES THE METHODS, TERMS, AND CRITERIA ASSOCIATED WITH THE DETERMINATION OF STUDENT PERFORMANCE OBJECTIVES. SELECTED EDUCATIONAL AND TRAINING RESEARCH LITERATURE WAS REVIEWED TO IDENTIFY PROCEDURES CURRENTLY USED IN DETERMINING INSTRUCTIONAL OBJECTIVES. A SURVEY OF EIGHT ARMY SERVICE SCHOOLS WAS CONDUCTED TO DETERMINE PROCEDURES…
McEwen, Jamie R.; Vamosi, Jana C.; Rogers, Sean M.
2013-01-01
Population differentiation can be driven in large part by natural selection, but selectively neutral evolution can play a prominent role in shaping patters of population divergence. The decomposition of the evolutionary history of populations into the relative effects of natural selection and selectively neutral evolution enables an understanding of the causes of population divergence and adaptation. In this study, we examined heterogeneous genomic divergence between alpine and lowland ecotypes of the allopolyploid plant, Anemone multifida. Using peak height and dominant AFLP data, we quantified population differentiation at non-outlier (neutral) and outlier loci to determine the potential contribution of natural selection and selectively neutral evolution to population divergence. We found 13 candidate loci, corresponding to 2.7% of loci, with signatures of divergent natural selection between alpine and lowland populations and between alpine populations (Fst = 0.074–0.445 at outlier loci), but neutral population differentiation was also evident between alpine populations (FST = 0.041–0.095 at neutral loci). By examining population structure at both neutral and outlier loci, we determined that the combined effects of selection and neutral evolution are associated with the divergence of alpine populations, which may be linked to extreme abiotic conditions and isolation between alpine sites. The presence of outlier levels of genetic variation in structured populations underscores the importance of separately analyzing neutral and outlier loci to infer the relative role of divergent natural selection and neutral evolution in population divergence. PMID:23874801
Method to control residual stress in a film structure and a system thereof
Parthum, Sr., Michael J.
2008-12-30
A method for controlling residual stress in a structure in a MEMS device and a structure thereof includes selecting a total thickness and an overall equivalent stress for the structure. A thickness for each of at least one set of alternating first and second layers is determined to control an internal stress with respect to a neutral axis for each of the at least alternating first and second layers and to form the structure based on the selected total thickness and the selected overall equivalent stress. Each of the at least alternating first and second layers is deposited to the determined thickness for each of the at least alternating first and second layers to form the structure.
[Charles Darwin and the problem of evolutionary progress].
Iordanskiĭ, N N
2010-01-01
According to Ch. Darwin's evolutionary theory, evolutionary progress (interpreted as morpho-physiological progress or arogenesis in recent terminology) is one of logical results of natural selection. At the same time, natural selection does not hold any factors especially promoting evolutionary progress. Darwin emphasized that the pattern of evolutionary changes depends on organism nature more than on the pattern of environment changes. Arogenesis specificity is determined by organization of rigorous biological systems - integral organisms. Onward progressive development is determined by fundamental features of living organisms: metabolism and homeostasis. The concept of social Darwinism differs fundamentally from Darwin's ideas about the most important role of social instincts in progress of mankind. Competition and selection play secondary role in socio-cultural progress of human society.
NASA Astrophysics Data System (ADS)
Ye, Fengying; Feng, Chenqi; Fu, Ning; Wu, Huihui; Jiang, Jibo; Han, Sheng
2015-12-01
A home-made carbon paste electrode (CPE) was reformed by graphene oxide (GO)/lanthanum (La) complexes, and a modified electrode, called GO-La/CPE, was fabricated for the selective determination of dopamine (DA) by cyclic voltammetry (CV) and differential pulse voltammetry (DPV). Several factors affecting the electrocatalytic performance of the modified sensor were investigated. Owning to the combination of GO and La ions, the GO-La/CPE sensor exhibited large surface area, well selectivity, good repeatability and stability in the oxidation reaction of DA. At optimal conditions, the response of the GO-La/CPE electrode for determining DA was linear in the region of 0.01-0.1 μM and 0.1-400.0 μM. The limit of detection was down to 0.32 nM (S/N = 3). In addition, this modified electrode was successfully applied to the detection of DA in real urine and serum samples by using standard adding method, showing its promising application in the electroanalysis of real samples.
NASA Astrophysics Data System (ADS)
Fu, Yu-Hsiang; Huang, Chung-Yuan; Sun, Chuen-Tsai
2016-11-01
Using network community structures to identify multiple influential spreaders is an appropriate method for analyzing the dissemination of information, ideas and infectious diseases. For example, data on spreaders selected from groups of customers who make similar purchases may be used to advertise products and to optimize limited resource allocation. Other examples include community detection approaches aimed at identifying structures and groups in social or complex networks. However, determining the number of communities in a network remains a challenge. In this paper we describe our proposal for a two-phase evolutionary framework (TPEF) for determining community numbers and maximizing community modularity. Lancichinetti-Fortunato-Radicchi benchmark networks were used to test our proposed method and to analyze execution time, community structure quality, convergence, and the network spreading effect. Results indicate that our proposed TPEF generates satisfactory levels of community quality and convergence. They also suggest a need for an index, mechanism or sampling technique to determine whether a community detection approach should be used for selecting multiple network spreaders.
Evaluation of methods for rapid determination of freezing point of aviation fuels
NASA Technical Reports Server (NTRS)
Mathiprakasam, B.
1982-01-01
Methods for identification of the more promising concepts for the development of a portable instrument to rapidly determine the freezing point of aviation fuels are described. The evaluation process consisted of: (1) collection of information on techniques previously used for the determination of the freezing point, (2) screening and selection of these techniques for further evaluation of their suitability in a portable unit for rapid measurement, and (3) an extensive experimental evaluation of the selected techniques and a final selection of the most promising technique. Test apparatuses employing differential thermal analysis and the change in optical transparency during phase change were evaluated and tested. A technique similar to differential thermal analysis using no reference fuel was investigated. In this method, the freezing point was obtained by digitizing the data and locating the point of inflection. Results obtained using this technique compare well with those obtained elsewhere using different techniques. A conceptual design of a portable instrument incorporating this technique is presented.
Nozari, Nazbanou; Hepner, Christopher R
2018-06-05
Competitive accounts of lexical selection propose that the activation of competitors slows down the selection of the target. Non-competitive accounts, on the other hand, posit that target response latencies are independent of the activation of competing items. In this paper, we propose a signal detection framework for lexical selection and show how a flexible selection criterion affects claims of competitive selection. Specifically, we review evidence from neurotypical and brain-damaged speakers and demonstrate that task goals and the state of the production system determine whether a competitive or a non-competitive selection profile arises. We end by arguing that there is conclusive evidence for a flexible criterion in lexical selection, and that integrating criterion shifts into models of language production is critical for evaluating theoretical claims regarding (non-)competitive selection.
[Methods for enzymatic determination of triglycerides in liver homogenates].
Höhn, H; Gartzke, J; Burck, D
1987-10-01
An enzymatic method is described for the determination of triacylglycerols in liver homogenate. In contrast to usual methods, higher reliability and selectivity are achieved by omitting the extraction step.
NASA Astrophysics Data System (ADS)
Mueller, David S.
2013-04-01
Selection of the appropriate extrapolation methods for computing the discharge in the unmeasured top and bottom parts of a moving-boat acoustic Doppler current profiler (ADCP) streamflow measurement is critical to the total discharge computation. The software tool, extrap, combines normalized velocity profiles from the entire cross section and multiple transects to determine a mean profile for the measurement. The use of an exponent derived from normalized data from the entire cross section is shown to be valid for application of the power velocity distribution law in the computation of the unmeasured discharge in a cross section. Selected statistics are combined with empirically derived criteria to automatically select the appropriate extrapolation methods. A graphical user interface (GUI) provides the user tools to visually evaluate the automatically selected extrapolation methods and manually change them, as necessary. The sensitivity of the total discharge to available extrapolation methods is presented in the GUI. Use of extrap by field hydrographers has demonstrated that extrap is a more accurate and efficient method of determining the appropriate extrapolation methods compared with tools currently (2012) provided in the ADCP manufacturers' software.
Ziegler, Andreas; Dohr, Gotrfried; Uchanska-Ziegler, Barbara
2002-07-01
Polymorphic genes of the human major histocompatibility complex [MHC; human leukocyte antigen (HLA)] are probably important in determining resistance to parasites and avoidance of inbreeding. We investigated whether HLA-associated sexual selection could also involve HLA-linked olfactory receptor (OR) genes, which might not only participate in olfaction-guided mate choice, but also in selection processes within the testis. The testicular expression status of HLA class I molecules (by immunohistology) and HLA-linked OR genes (by transcriptional analysis) was determined. Various HLA class I heavy chains, but not beta2-microglobulin (beta2m), were expressed, mainly at the spermatocyte I stage. Of 17 HLA-linked OR genes analyzed, eight were found to be transcribed in the testis. They exhibited varying numbers of 5'- or 3'-non-coding exons as well as differential splicing. We suggest that testis-expressed polymorphic HLA and OR proteins are functionally connected and serve the selection of spermatozoa, enabling them to distinguish 'self from 'non-self [the sperm-receptor-selection (SRS) hypothesis].
NASA Technical Reports Server (NTRS)
Reid, G. F.
1976-01-01
A technique is presented for determining state variable feedback gains that will place both the poles and zeros of a selected transfer function of a dual-input control system at pre-determined locations in the s-plane. Leverrier's algorithm is used to determine the numerator and denominator coefficients of the closed-loop transfer function as functions of the feedback gains. The values of gain that match these coefficients to those of a pre-selected model are found by solving two systems of linear simultaneous equations. The algorithm has been used in a computer simulation of the CH-47 helicopter to control longitudinal dynamics.
Absolute determination of power density in the VVER-1000 mock-up on the LR-0 research reactor.
Košt'ál, Michal; Švadlenková, Marie; Milčák, Ján
2013-08-01
The work presents a detailed comparison of calculated and experimentally determined net peak areas of selected fission products gamma lines. The fission products were induced during a 2.5 h irradiation on the power level of 9.5 W in selected fuel pins of the VVER-1000 Mock-Up. The calculations were done with deterministic and stochastic (Monte Carlo) methods. The effects of different nuclear data libraries used for calculations are discussed as well. The Net Peak Area (NPA) may be used for the determination of fission density across the mock-up. This fission density is practically identical to power density. Copyright © 2013 Elsevier Ltd. All rights reserved.
Rüter, J; Raczek, D I
1992-06-01
A sensitive and selective high pressure liquid chromatography (HPLC) procedure for the determination of sodium cyclamate in juices and preserves is presented. The method depends on the oxidation of cyclamate to cyclohexylamine, which then is converted prechromatographically into a fluorescent derivative. It is analyzed by HPLC on a C18:reversed-phase column and determined with fluorescence detection (excitation at 350 nm, emission at 440-650 nm). The detection limit of sodium cyclamate was 0.5-5 mg/kg, depending on the nature and dilution of the samples. The relative standard deviations thus obtained were +/- 1.0 to +/- 2.6%. The average recovery was 90%.
Federal Register 2010, 2011, 2012, 2013, 2014
2013-08-20
...The EPA has made a proposed determination that a reduction in recurring expenditures of non-Federal funds for the Lane Regional Air Protection Agency (LRAPA) in Eugene, Oregon is a result of agency wide non-selective reductions in expenditures. This determination, when final, will permit the LRAPA to continue to receive grant funding under Section 105 of the Clean Air Act for the state fiscal year (SFY) 2014. This determination will also reset the LRAPA required maintenance of effort level for SFY 2012 and 2013 to reflect the non-selective reductions made to address reductions in revenue due to adverse economic conditions in Lane County, Oregon.
DOT National Transportation Integrated Search
2008-05-01
The Montana Department of Transportation (MDT) contracted the Bureau of Business and Economic Research at the University of Montana Missoula to conduct research to determine how other states solicit, prioritize, and select research problem statem...
CONTAMINANTS AND REMEDIAL OPTIONS AT SELECTED METAL-CONTAMINATED SITES
This document provides information that facilitates characterization of the site and selection of treatment technologies at metals-contaminated sites that would be capable of meeting site-specific cleanup levels. he document does not facilitate the determination of cleanup levels...
40 CFR 89.117 - Test fleet selection.
Code of Federal Regulations, 2010 CFR
2010-07-01
...) CONTROL OF EMISSIONS FROM NEW AND IN-USE NONROAD COMPRESSION-IGNITION ENGINES Emission Standards and... establishing deterioration factors, the manufacturer shall select the engines, subsystems, or components to be used to determine exhaust emission deterioration factors for each engine-family control system...
32 CFR 903.3 - Selection criteria.
Code of Federal Regulations, 2011 CFR
2011-07-01
... are selected on the basis of demonstrated character, test scores, medical examination, prior academic... Board (DODMERB). (3) Have an acceptable academic record as determined by HQ USAFA/RR. Each applicant... would enhance diversity at USAFA, such as unique academic abilities, language skills, demonstrated...
Davarani, Saied Saeed Hosseiny; Moazami, Hamid Reza; Keshtkar, Ali Reza; Banitaba, Mohammad Hossein; Nojavan, Saeed
2013-06-14
A novel method for the selective electromembrane extraction (EME) of U(6+) prior to fluorometric determination has been proposed. The effect of extraction conditions including supported liquid membrane (SLM) composition, extraction time and extraction voltage were investigated. An SLM composition of 1% di-2-ethyl hexyl phosphonic acid in nitrophenyl octyl ether (NPOE) showed good selectivity, recovery and enrichment factor. The best performance was achieved at an extraction potential of 80 volts and an extraction time of 14 minutes Under the optimized conditions, a linear range from 1 to 1000 ng mL(-1) and LOD of 0.1 ng mL(-1) were obtained for the determination of U(6+). The EME method showed good performance in sample cleanup and the reduction of the interfering effects of Mn(2+), Zn(2+), Cd(2+), Ni(2+), Fe(3+), Co(2+), Cu(2+), Cl(-) and PO4(3-) ions during fluorometric determination of uranium in real water samples. The recoveries above 54% and enrichment factors above 64.7 were obtained by the proposed method for real sample analysis. Copyright © 2013 Elsevier B.V. All rights reserved.
Employee Choice of a High-Deductible Health Plan across Multiple Employers
Lave, Judith R; Men, Aiju; Day, Brian T; Wang, Wei; Zhang, Yuting
2011-01-01
Objective To determine factors associated with selecting a high-deductible health plan (HDHP) rather than a preferred provider plan (PPO) and to examine switching and market segmentation after initial selection. Data Sources/Study Setting Claims and benefit information for 2005–2007 from nine employers in western Pennsylvania first offering HDHP in 2006. Study Design We examined plan growth over time, used logistic regression to determine factors associated with choosing an HDHP, and examined the distribution of healthy and sick members across plan types. Data Extraction We linked employees with their dependents to determine family-level variables. We extracted risk scores, covered charges, employee age, and employee gender from claims data. We determined census-level race, education, and income information. Principal Findings Health status, gender, race, and education influenced the type of individual and family policies chosen. In the second year the HDHP was offered, few employees changed plans. Risk segmentation between HDHPs and PPOs existed, but it did not increase. Conclusions When given a choice, those who are healthier are more likely to select an HDHP leading to risk segmentation. Risk segmentation did not increase in the second year that HDHPs were offered. PMID:20849558
Martínez-Carballo, Elena; González-Barreiro, Carmen; Sitka, Andrea; Kreuzinger, Norbert; Scharf, Sigrid; Gans, Oliver
2007-03-01
Soxhlet extraction and high-performance liquid chromatography (HPLC) coupled to tandem mass spectrometry detection (MS/MS) was used for the determination of selected quaternary ammonium compounds (QACs) in solid samples. The method was applied for the determination of alkyl benzyl, dialkyl and trialkyl quaternary ammonium compounds in sediment and sludge samples in Austria. The overall method quantification limits range from 0.6 to 3 microg/kg for sediments and from 2 to 5 microg/kg for sewage sludges. Mean recoveries between 67% and 95% are achieved. In general sediments were especially contaminated by C12 chain benzalkonium chloride (BAC-C12) as well as by the long C-chain dialkyldimethylammonium chloride (DDAC-C18) with a maximum concentration of 3.6 mg/kg and 2.1mg/kg, respectively. Maxima of 27 mg/kg for DDAC-C10, 25 mg/kg for BAC-C12 and 23 mg/kg for BAC-C14 were determined for sludge samples. The sums of the 12 selected target compounds range from 22 mg/kg to 103 mg/kg in the sludge samples.
Ventura-Cordero, J; González-Pech, P G; Jaimez-Rodriguez, P R; Ortiz-Ocampo, G I; Sandoval-Castro, C A; Torres-Acosta, J F J
2018-06-01
Previous cafeteria studies suggested that a moderate natural gastrointestinal nematode (GIN) infection did not modify the resource selection of adult Criollo goats towards tannin-rich plants compared with worm-free goats. A higher infection with Haemonchus contortus could trigger a change in the resource selection behaviour towards tannin-rich foliage. Alternatively, goats might select plant species solely to meet their nutritional requirements. A cafeteria study investigated the effect of a high artificial infection with H. contortus on the feed resource selection of goats. Adult Criollo goats (37.5±4.8 kg BW) with browsing experience were distributed in two groups: the infected group (IG) with six animals artificially infected with H. contortus (6000 L3/animal); and the non-infected group (NIG) with six animals maintained worm-free. The experiment included two 5-day periods with additional 5-day adaptation period. In the first period, animals were offered foliage of five plant species with a decreasing gradient of condensed tannins (CT) (Mimosa bahamensis, Gymnopodium floribundum, Havardia albicans, Acacia pennatula, Lysiloma latisiliqum), and three plant species with negligible CT content (Leucaena leucocephala, Piscidia piscipula and Brosimum alicastrum). In the second period the foliage of B. alicastrum was withdrawn. A grain-based concentrate feed was offered daily at 1% BW in DM basis. Dry matter and nutrient intake was determined. Foliage selection of each experimental group was determined using the Chesson selection index. The H. contortus egg count per gram of faeces (EPG) was determined for infected goats twice daily. Chesson index showed a similar pattern of foliage selection on periods 1 and 2. Mean EPG of goats in IG was 2028±259 EPG during period 1 and 1 293±198 EPG during period 2 (P>0.05). During period 1, the selection pattern was highest for B. alicastrum (tannin-free), followed by a tannin-rich plant (M. bahamensis). These two plants remained as highly selected during period 2. The Chesson index showed that both experimental groups (IG and NIG) selected the same plant species in both periods. Thus, a high H. contortus infection did not affect selection of goats fed with CT-rich plants. Apparently, goats balanced their nutrient intake with the plants selected, showing evidence of nutritional wisdom. This balance may have helped to prevent excess protein in the diet and also to maintain a low GIN infection, both considered as examples of prophylactic self-medication.
Levels and limits in artificial selection of communities.
Blouin, Manuel; Karimi, Battle; Mathieu, Jérôme; Lerch, Thomas Z
2015-10-01
Artificial selection of individuals has been determinant in the elaboration of the Darwinian theory of natural selection. Nowadays, artificial selection of ecosystems has proven its efficiency and could contribute to a theory of natural selection at several organisation levels. Here, we were not interested in identifying mechanisms of adaptation to selection, but in establishing the proof of principle that a specific structure of interaction network emerges under ecosystem artificial selection. We also investigated the limits in ecosystem artificial selection to evaluate its potential in terms of managing ecosystem function. By artificially selecting microbial communities for low CO2 emissions over 21 generations (n = 7560), we found a very high heritability of community phenotype (52%). Artificial selection was responsible for simpler interaction networks with lower interaction richness. Phenotype variance and heritability both decreased across generations, suggesting that selection was more likely limited by sampling effects than by stochastic ecosystem dynamics. © 2015 John Wiley & Sons Ltd/CNRS.
Selection and Characterization of Vegetable Crop Cultivars for use in Advanced Life Support Systems
NASA Technical Reports Server (NTRS)
Langhans, Robert W.
1997-01-01
Cultivar evaluation for controlled environments is a lengthy and multifaceted activity. The chapters of this thesis cover eight steps preparatory to yield trials, and the final step of cultivar selection after data are collected. The steps are as follows: 1. Examination of the literature on the crop and crop cultivars to assess the state of knowledge. 2. Selection of standard cultivars with which to explore crop response to major growth factors and determine set points for screening and, later, production. 3. Determination of practical growing techniques for the crop in controlled environments. 4. Design of experiments for determination of crop responses to the major growth factors, with particular emphasis on photoperiod, daily light integral and air temperature. 5. Developing a way of measuring yield appropriate to the crop type by sampling through the harvest period and calculating a productivity function. 6. Narrowing down the pool of cultivars and breeding lines according to a set of criteria and breeding history. 7. Determination of environmental set points for cultivar evaluation through calculating production cost as a function of set points and size of target facility. 8. Design of screening and yield trial experiments emphasizing efficient use of space. 9. Final evaluation of cultivars after data collection, in terms of production cost and value to the consumer. For each of the steps, relevant issues are addressed. In selecting standards to determine set points for screening, set points that optimize cost of production for the standards may not be applicable to all cultivars. Production of uniform and equivalent- sized seedlings is considered as a means of countering possible differences in seed vigor. Issues of spacing and re-spacing are also discussed.
Boroumand, Samira; Chamjangali, Mansour Arab; Bagherian, Ghadamali
2017-03-05
A simple and sensitive double injection/single detector flow injection analysis (FIA) method is proposed for the simultaneous kinetic determination of ascorbic acid (AA) and uric acid (UA). This method is based upon the difference between the rates of the AA and UA reactions with Fe 3+ in the presence of 1, 10-phenanthroline (phen). The absorbance of Fe 2+ /1, 10-phenanthroline (Fe-phen) complex obtained as the product was measured spectrophotometrically at 510nm. To reach a good accuracy in the differential kinetic determination via the mathematical manipulations of the transient signals, different criteria were considered in the selection of the optimum conditions. The multi criteria decision making (MCDM) approach was applied for the selection of the optimum conditions. The importance weights of the evaluation criteria were determined using the analytic hierarchy process, entropy method, and compromised weighting (CW). The experimental conditions (alternatives) were ranked by the technique for order preference by similarity to an ideal solution. Under the selected optimum conditions, the obtained analytical signals were linear in the ranges of 0.50-5.00 and 0.50-4.00mgL -1 for AA and UA, respectively. The 3σ detection limits were 0.07mgL -1 for AA and 0.12mgL -1 for UA. The relative standard deviations for four replicate determinations of AA and UA were 2.03% and 3.30% respectively. The method was also applied for the analysis of analytes in the blood serum, Vitamine C tablets, and tap water with satisfactory results. Copyright © 2016. Published by Elsevier B.V.
NASA Astrophysics Data System (ADS)
Boroumand, Samira; Chamjangali, Mansour Arab; Bagherian, Ghadamali
2017-03-01
A simple and sensitive double injection/single detector flow injection analysis (FIA) method is proposed for the simultaneous kinetic determination of ascorbic acid (AA) and uric acid (UA). This method is based upon the difference between the rates of the AA and UA reactions with Fe3 + in the presence of 1, 10-phenanthroline (phen). The absorbance of Fe2 +/1, 10-phenanthroline (Fe-phen) complex obtained as the product was measured spectrophotometrically at 510 nm. To reach a good accuracy in the differential kinetic determination via the mathematical manipulations of the transient signals, different criteria were considered in the selection of the optimum conditions. The multi criteria decision making (MCDM) approach was applied for the selection of the optimum conditions. The importance weights of the evaluation criteria were determined using the analytic hierarchy process, entropy method, and compromised weighting (CW). The experimental conditions (alternatives) were ranked by the technique for order preference by similarity to an ideal solution. Under the selected optimum conditions, the obtained analytical signals were linear in the ranges of 0.50-5.00 and 0.50-4.00 mg L- 1 for AA and UA, respectively. The 3σ detection limits were 0.07 mg L- 1 for AA and 0.12 mg L- 1 for UA. The relative standard deviations for four replicate determinations of AA and UA were 2.03% and 3.30% respectively. The method was also applied for the analysis of analytes in the blood serum, Vitamine C tablets, and tap water with satisfactory results.
ERIC Educational Resources Information Center
Araiza, Ricardo
2011-01-01
Purpose: The purpose of this replication study was to determine the degree to which teachers and administrators in selected low-achieving Title I elementary schools: 1. Report that they teach the following test-taking skills to prepare their students to take the CST: establishing an appropriate student attitude toward testing, familiarity with the…
The Nature of Selection and Judging for the Teacher of the Year Award.
ERIC Educational Resources Information Center
McKenna, Bonnie; And Others
This paper reports on the investigation of the operation of the Teacher of the Year Award program in 28 states. It focuses on the method of selection for recipients of this award, and explores the nature of the judging process used in selecting candidates at both the state and national levels. Specific objectives are: (1) to determine the criteria…
Determinants of First-Term Attrition for Enlisted and Officer Selected Marine Corps Reservists
2015-03-01
FIRST-TERM ATTRITION FOR ENLISTED AND OFFICER SELECTED MARINE CORPS RESERVISTS by Ugur Ugurbas Mustafa Korkmaz March 2015 Thesis Advisors...ATTRITION FOR ENLISTED AND OFFICER SELECTED MARINE CORPS RESERVISTS Ugur Ugurbas Captain, Turkish Army B.S., Turkish Army Academy, 2006 Mustafa...the degree of MASTER OF SCIENCE IN MANAGEMENT from the NAVAL POSTGRADUATE SCHOOL March 2015 Authors: Ugur Ugurbas Mustafa
The Risk of Adverse Impact in Selections Based on a Test with Known Effect Size
ERIC Educational Resources Information Center
De Corte, Wilfried; Lievens, Filip
2005-01-01
The authors derive the exact sampling distribution function of the adverse impact (AI) ratio for single-stage, top-down selections using tests with known effect sizes. Subsequently, it is shown how this distribution function can be used to determine the risk that a future selection decision on the basis of such tests will result in an outcome that…
Day of Launch Profile Selection for Pad Abort Guidance
NASA Technical Reports Server (NTRS)
Whitley, Ryan J.
2010-01-01
A day of launch selection approach that involves choosing from an array of pitch profiles of varying loft was analyzed with the purpose of reducing the risk of a land landing failure during a pad abort. It was determined that selecting from three pitch profiles can reduce the number of waterline abort performance requirement failures approximately in half without compromising other performance metrics.
Mazurek, Artur; Jamroz, Jerzy
2015-04-15
In food analysis, a method for determination of vitamin C should enable measuring of total content of ascorbic acid (AA) and dehydroascorbic acid (DHAA) because both chemical forms exhibit biological activity. The aim of the work was to confirm applicability of HPLC-DAD method for analysis of total content of vitamin C (TC) and ascorbic acid in various types of food by determination of validation parameters such as: selectivity, precision, accuracy, linearity and limits of detection and quantitation. The results showed that the method applied for determination of TC and AA was selective, linear and precise. Precision of DHAA determination by the subtraction method was also evaluated. It was revealed that the results of DHAA determination obtained by the subtraction method were not precise which resulted directly from the assumption of this method and the principles of uncertainty propagation. The proposed chromatographic method should be recommended for routine determinations of total vitamin C in various food. Copyright © 2014 Elsevier Ltd. All rights reserved.
Evolution and the complexity of bacteriophages.
Serwer, Philip
2007-03-13
The genomes of both long-genome (> 200 Kb) bacteriophages and long-genome eukaryotic viruses have cellular gene homologs whose selective advantage is not explained. These homologs add genomic and possibly biochemical complexity. Understanding their significance requires a definition of complexity that is more biochemically oriented than past empirically based definitions. Initially, I propose two biochemistry-oriented definitions of complexity: either decreased randomness or increased encoded information that does not serve immediate needs. Then, I make the assumption that these two definitions are equivalent. This assumption and recent data lead to the following four-part hypothesis that explains the presence of cellular gene homologs in long bacteriophage genomes and also provides a pathway for complexity increases in prokaryotic cells: (1) Prokaryotes underwent evolutionary increases in biochemical complexity after the eukaryote/prokaryote splits. (2) Some of the complexity increases occurred via multi-step, weak selection that was both protected from strong selection and accelerated by embedding evolving cellular genes in the genomes of bacteriophages and, presumably, also archaeal viruses (first tier selection). (3) The mechanisms for retaining cellular genes in viral genomes evolved under additional, longer-term selection that was stronger (second tier selection). (4) The second tier selection was based on increased access by prokaryotic cells to improved biochemical systems. This access was achieved when DNA transfer moved to prokaryotic cells both the more evolved genes and their more competitive and complex biochemical systems. I propose testing this hypothesis by controlled evolution in microbial communities to (1) determine the effects of deleting individual cellular gene homologs on the growth and evolution of long genome bacteriophages and hosts, (2) find the environmental conditions that select for the presence of cellular gene homologs, (3) determine which, if any, bacteriophage genes were selected for maintaining the homologs and (4) determine the dynamics of homolog evolution. This hypothesis is an explanation of evolutionary leaps in general. If accurate, it will assist both understanding and influencing the evolution of microbes and their communities. Analysis of evolutionary complexity increase for at least prokaryotes should include analysis of genomes of long-genome bacteriophages.
Determinants of Social Accountability in Iranian Nursing and Midwifery Schools: A Delphi Study.
Salehmoghaddam, Amir Reza; Mazloom, Seyed Reza; Sharafkhani, Mohammad; Gholami, Hassan; Emami Zeydi, Amir; Khorashadizadeh, Fatemeh; Emadzadeh, Ali
2017-04-01
Revising the medical education programs to meet the needs of society has become both a necessity and an important priority due to the considerable increase of population, changing patterns of diseases, and new health priorities. While this necessity has been highlighted in Iran's Fifth Development Plan as well as its National 2025 Vision Plan, the determinants of social accountability have not been explained yet. This study aimed to develop determinants of social accountability in the Iranian Nursing and Midwifery Schools. This classic Delphi study included thirty experts in Nursing and Midwifery Education, Research and Services selected based on purposive sampling and three rounds of Delphi technique and conducted in Nursing and Midwifery School of Mashhad University of Medical Sciences. The primary data were collected using an initial structured questionnaire prepared through extensive review of literature. SPSS 11.5 software was used to analyze the data. The interquartile deviation and percentage of agreement were also used to study the consensus of opinion by experts. Finding obtained from the rounds of Delphi resulted in selecting 69 determinants out of the initial pool of 128 primary determinants of social accountability. The items were selected based on experts' consensus and categorized under three main activities of Nursing and Midwifery School, namely education, research, and service. Social accountability determinants were explained by 69 items for Schools of Nursing and Midwifery in Iran. The proposed determinants can be used by managers and authorities of Nursing and Midwifery School, policy makers, and evaluating institutions associated with them to ensure realizing social accountability goals.
Mahu, Ştefania Corina; Hăncianu, Monica; Agoroaei, Luminiţa; Grigoriu, Ioana Cezara; Strugaru, Anca Monica; Butnaru, Elena
2015-01-01
Hypertension is one of the most common causes of death, a complex and incompletely controlled disease for millions of patients. Metoprolol, bisoprolol, nebivolol and atenolol are selective beta-blockers frequently used in the management of arterial hypertension, alone or in fixed combination with other substances. This study presents the most used analytical methods for simultaneous determination in biological fluids of fixed combinations containing selective beta-blockers. Articles in Pub-Med, Science Direct and Wiley Journals databases published between years 2004-2014 were reviewed. Methods such as liquid chromatography--mass spectrometry--mass spectrometry (LC-MS/MS), high performance liquid chromatography (HPLC) or high performance liquid chromatography--mass spectrometry (HPLC-MS) were used for determination of fixed combination with beta-blockers in human plasma, rat plasma and human breast milk. LC-MS/MS method was used for simultaneous determination of fixed combinations of metoprolol with simvastatin, hydrochlorothiazide or ramipril, combinations of nebivolol and valsartan, or atenolol and amlodipine. Biological samples were processed by protein precipitation techniques or by liquid-liquid extraction. For the determination of fixed dose combinations of felodipine and metoprolol in rat plasma liquid chromatography--electrospray ionization--mass spectrometry (LC-ESI-MS/MS) was applied, using phenacetin as internal standard. HPLC-MS method was applied for the determination of bisoprolol and hydrochlorothiazide in human plasma. For the determination of atenolol and chlorthalidone from human breast milk and human plasma the HPLC method was used. The analytical methods were validated according to the specialized guidelines, and were applied to biological samples, thing that confirms the permanent concern of researchers in this field.
40 CFR 1051.243 - How do I determine deterioration factors from exhaust durability testing?
Code of Federal Regulations, 2010 CFR
2010-07-01
... PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS CONTROL OF EMISSIONS FROM RECREATIONAL ENGINES AND..., select vehicles, engines, subsystems, or components for testing. Determine deterioration factors based on...
Surveillance system and method having parameter estimation and operating mode partitioning
NASA Technical Reports Server (NTRS)
Bickford, Randall L. (Inventor)
2005-01-01
A system and method for monitoring an apparatus or process asset including creating a process model comprised of a plurality of process submodels each correlative to at least one training data subset partitioned from an unpartitioned training data set and each having an operating mode associated thereto; acquiring a set of observed signal data values from the asset; determining an operating mode of the asset for the set of observed signal data values; selecting a process submodel from the process model as a function of the determined operating mode of the asset; calculating a set of estimated signal data values from the selected process submodel for the determined operating mode; and determining asset status as a function of the calculated set of estimated signal data values for providing asset surveillance and/or control.
[Contextual indicators to assess social determinants of health and the Spanish economic recession].
Cabrera-León, Andrés; Daponte Codina, Antonio; Mateo, Inmaculada; Arroyo-Borrell, Elena; Bartoll, Xavier; Bravo, María José; Domínguez-Berjón, María Felicitas; Renart, Gemma; Álvarez-Dardet, Carlos; Marí-Dell'Olmo, Marc; Bolívar Muñoz, Julia; Saez, Marc; Escribà-Agüir, Vicenta; Palència, Laia; López, María José; Saurina, Carme; Puig, Vanessa; Martín, Unai; Gotsens, Mercè; Borrell, Carme; Serra Saurina, Laura; Sordo, Luis; Bacigalupe, Amaia; Rodríguez-Sanz, Maica; Pérez, Glòria; Espelt, Albert; Ruiz, Miguel; Bernal, Mariola
To provide indicators to assess the impact on health, its social determinants and health inequalities from a social context and the recent economic recession in Spain and its autonomous regions. Based on the Spanish conceptual framework for determinants of social inequalities in health, we identified indicators sequentially from key documents, Web of Science, and organisations with official statistics. The information collected resulted in a large directory of indicators which was reviewed by an expert panel. We then selected a set of these indicators according to geographical (availability of data according to autonomous regions) and temporal (from at least 2006 to 2012) criteria. We identified 203 contextual indicators related to social determinants of health and selected 96 (47%) based on the above criteria; 16% of the identified indicators did not satisfy the geographical criteria and 35% did not satisfy the temporal criteria. At least 80% of the indicators related to dependence and healthcare services were excluded. The final selection of indicators covered all areas for social determinants of health, and 62% of these were not available on the Internet. Around 40% of the indicators were extracted from sources related to the Spanish Statistics Institute. We have provided an extensive directory of contextual indicators on social determinants of health and a database to facilitate assessment of the impact of the economic recession on health and health inequalities in Spain and its autonomous regions. Copyright © 2016 SESPAS. Publicado por Elsevier España, S.L.U. All rights reserved.
Motivation of medical students: selection by motivation or motivation by selection.
Wouters, Anouk; Croiset, Gerda; Galindo-Garre, Francisca; Kusurkar, Rashmi A
2016-01-29
Medical schools try to implement selection procedures that will allow them to select the most motivated students for their programs. Though there is a general feeling that selection stimulates student motivation, conclusive evidence for this is lacking. The current study aims to use the perspective of Self-determination Theory (SDT) of motivation as a lens to examine how medical students' motivation differs in relation to different selection procedures. The hypotheses were that 1) selected students report higher strength and autonomous motivation than non-selected students, and 2) recently selected students report higher strength and autonomous motivation than non-selected students and students who were selected longer ago. First- (Y1) and fourth-year (Y4) medical students in the six-year regular programme and first-year students in the four-year graduate entry programme (GE) completed questionnaires measuring motivation strength and type (autonomous-AM, controlled-CM). Scores were compared between students admitted based on selection, lottery or top pre-university GPA (top GPA) using ANCOVAs. Selected students' answers on open-ended questions were analysed using inductive thematic analysis to identify reasons for changes in motivation. The response rate was 61.4 % (n = 357). Selected students (Y1, Y4 and GE) reported a significantly higher strength of motivation than non-selected students (Y1 and Y4 lottery and top GPA) (p < 0.01). Recently selected students (Y1 and GE) reported significantly higher strength (p < 0.01) and higher AM (p < 0.01) and CM (p < 0.05) than non-selected students (lottery and top GPA) and Y4 students who were selected three years ago. Students described that being selected enhanced their motivation as they felt autonomous, competent and that they belonged to a special group. These reported reasons are in alignment with the basic psychological needs described by Self-Determination Theory as important in enhancing autonomous motivation. A comprehensive selection procedure, compared to less demanding admission procedures, does not seem to yield a student population which stands out in terms of autonomous motivation. The current findings indicate that selection might temporarily enhance students' motivation. The mechanism through which this occurs seems to be through feelings of autonomy, competence and relatedness inspired by selection.
Diverse protist grazers select for virulence-related traits in Legionella
Amaro, Francisco; Wang, Wen; Gilbert, Jack A; Roger Anderson, O; Shuman, Howard A
2015-01-01
It is generally accepted that selection for resistance to grazing by protists has contributed to the evolution of Legionella pneumophila as a pathogen. Grazing resistance is becoming more generally recognized as having an important role in the ecology and evolution of bacterial pathogenesis. However, selection for grazing resistance presupposes the existence of protist grazers that provide the selective pressure. To determine whether there are protists that graze on pathogenic Legionella species, we investigated the existence of such organisms in a variety of environmental samples. We isolated and characterized diverse protists that graze on L. pneumophila and determined the effects of adding L. pneumophila on the protist community structures in microcosms made from these environmental samples. Several unrelated organisms were able to graze efficiently on L. pneumophila. The community structures of all samples were markedly altered by the addition of L. pneumophila. Surprisingly, some of the Legionella grazers were closely related to species that are known hosts for L. pneumophila, indicating the presence of unknown specificity determinants for this interaction. These results provide the first direct support for the hypothesis that protist grazers exert selective pressure on Legionella to acquire and retain adaptations that contribute to survival, and that these properties are relevant to the ability of the bacteria to cause disease in people. We also report a novel mechanism of killing of amoebae by one Legionella species that requires an intact Type IV secretion system but does not involve intracellular replication. We refer to this phenomenon as ‘food poisoning'. PMID:25575308
Controlling prescription drug expenditures: a report of success.
Miller, David P; Furberg, Curt D; Small, Ronald H; Millman, Franklyn M; Ambrosius, Walter T; Harshbarger, Julia S; Ohl, Christopher A
2007-08-01
To determine whether a multi-interventional program can limit increases in prescription drug expenditures while maintaining utilization of needed medications. Quasi-experimental, pre-post design. The program included formulary changes, quantity limits, and mandatory pill splitting for select drugs implemented in phases. We assessed the short-term effects of each intervention by comparing class-specific drug spending and generic medication use before and after benefit changes. Long-term effects were determined by comparing overall spending with projected spending estimates, and by examining changes in the planwide use of generic medications over time. Effects on medication utilization were assessed by examining members' use of selected classes of chronic medications before and after the policy changes. Over 3 years, the plan and members saved $6.6 million attributed to the interventions. Most of the savings were due to the reclassification of select brand-name drugs to nonpreferred status (estimated annual savings, $941,000), followed by the removal of nonsedating antihistamines from the formulary (annual savings, $565,000), and the introduction of pill splitting (annual savings, $342,000). Limiting quantities of select medications had the smallest impact (annual savings, $135,000). Members' use of generic medications steadily increased from 40% to 57%. Although 17.5% of members stopped using at least 1 class of selected medications, members' total use of chronic medications remained constant. A combination of interventions can successfully manage prescription drug spending while preserving utilization of chronic medications. Additional studies are needed to determine the effect of these cost-control interventions on other health outcomes.
A Guide for Expatriate Training.
ERIC Educational Resources Information Center
Wentland, Daniel
Implementation of a thorough expatriate selection process and an effective cross-cultural training (CCT) program can reduce expatriate failure rates. The selection process must determine compatibility and receptiveness of an employee and his or her family to an assignment overseas through worldwide recruitment, companywide screening for…
Detection of antistripping additives with quick bottle test.
DOT National Transportation Integrated Search
1980-01-01
Several variations of the quick bottle test were evaluated to determine the procedure having the best repeatability. Naphtha was selected over kerosene and white gas as the solvent for use in the test, and room temperature was selected over 140F as...
Alphabetical Order Effects in School Admissions
ERIC Educational Resources Information Center
Jurajda, Štepán; Münich, Daniel
2016-01-01
If school admission committees use alphabetically sorted lists of applicants in their evaluations, one's position in the alphabet according to last name initial may be important in determining access to selective schools. Jurajda and Münich (2010) "Admission to Selective Schools, Alphabetically". "Economics of Education…
Web Site Credibility: Why Do People Believe What They Believe?
ERIC Educational Resources Information Center
Iding, Marie K.; Crosby, Martha E.; Auernheimer, Brent; Klemm, E. Barbara
2009-01-01
This research investigates university students' determinations of credibility of information on Web sites, confidence in their determinations, and perceptions of Web site authors' vested interests. In Study 1, university-level computer science and education students selected Web sites determined to be credible and Web sites that exemplified…
Using Dominance Analysis to Determine Predictor Importance in Logistic Regression
ERIC Educational Resources Information Center
Azen, Razia; Traxel, Nicole
2009-01-01
This article proposes an extension of dominance analysis that allows researchers to determine the relative importance of predictors in logistic regression models. Criteria for choosing logistic regression R[superscript 2] analogues were determined and measures were selected that can be used to perform dominance analysis in logistic regression. A…
DOT National Transportation Integrated Search
1981-05-01
Development of a nuclear density gage for determining the degree of consolidation of plastic concrete in selected horizontal layers was determined to be feasible. A commercially available, with some modifications, two-probe density gage (detector in ...
40 CFR 761.257 - Determining the regulatory status of sampled pipe.
Code of Federal Regulations, 2010 CFR
2010-07-01
... COMMERCE, AND USE PROHIBITIONS Determining a PCB Concentration for Purposes of Abandonment or Disposal of Natural Gas Pipeline: Selecting Sample Sites, Collecting Surface Samples, and Analyzing Standard PCB Wipe... disposal of a pipe segment that has been sampled, the sample results for that segment determines its PCB...
48 CFR 22.1012-1 - Prevailing wage determinations.
Code of Federal Regulations, 2013 CFR
2013-10-01
.... (The telephone number is provided on the e98 website.) [71 FR 36934, June 28, 2006] ... publication of the revised prevailing wage determination on the website. (ii) For purposes of using the e98...) In selecting a prevailing wage determination from the WDOL website for use in a solicitation or other...
48 CFR 22.1012-1 - Prevailing wage determinations.
Code of Federal Regulations, 2014 CFR
2014-10-01
.... (The telephone number is provided on the e98 website.) [71 FR 36934, June 28, 2006] ... of the revised prevailing wage determination on the website. (ii) For purposes of using the e98...) In selecting a prevailing wage determination from the WDOL website for use in a solicitation or other...
48 CFR 22.1012-1 - Prevailing wage determinations.
Code of Federal Regulations, 2012 CFR
2012-10-01
.... (The telephone number is provided on the e98 website.) [71 FR 36934, June 28, 2006] ... publication of the revised prevailing wage determination on the website. (ii) For purposes of using the e98...) In selecting a prevailing wage determination from the WDOL website for use in a solicitation or other...
48 CFR 22.1012-1 - Prevailing wage determinations.
Code of Federal Regulations, 2011 CFR
2011-10-01
.... (The telephone number is provided on the e98 website.) [71 FR 36934, June 28, 2006] ... publication of the revised prevailing wage determination on the website. (ii) For purposes of using the e98...) In selecting a prevailing wage determination from the WDOL website for use in a solicitation or other...
Identification of atypical flight patterns
NASA Technical Reports Server (NTRS)
Statler, Irving C. (Inventor); Ferryman, Thomas A. (Inventor); Amidan, Brett G. (Inventor); Whitney, Paul D. (Inventor); White, Amanda M. (Inventor); Willse, Alan R. (Inventor); Cooley, Scott K. (Inventor); Jay, Joseph Griffith (Inventor); Lawrence, Robert E. (Inventor); Mosbrucker, Chris (Inventor)
2005-01-01
Method and system for analyzing aircraft data, including multiple selected flight parameters for a selected phase of a selected flight, and for determining when the selected phase of the selected flight is atypical, when compared with corresponding data for the same phase for other similar flights. A flight signature is computed using continuous-valued and discrete-valued flight parameters for the selected flight parameters and is optionally compared with a statistical distribution of other observed flight signatures, yielding atypicality scores for the same phase for other similar flights. A cluster analysis is optionally applied to the flight signatures to define an optimal collection of clusters. A level of atypicality for a selected flight is estimated, based upon an index associated with the cluster analysis.
Universal statistics of selected values
NASA Astrophysics Data System (ADS)
Smerlak, Matteo; Youssef, Ahmed
2017-03-01
Selection, the tendency of some traits to become more frequent than others under the influence of some (natural or artificial) agency, is a key component of Darwinian evolution and countless other natural and social phenomena. Yet a general theory of selection, analogous to the Fisher-Tippett-Gnedenko theory of extreme events, is lacking. Here we introduce a probabilistic definition of selection and show that selected values are attracted to a universal family of limiting distributions which generalize the log-normal distribution. The universality classes and scaling exponents are determined by the tail thickness of the random variable under selection. Our results provide a possible explanation for skewed distributions observed in diverse contexts where selection plays a key role, from molecular biology to agriculture and sport.
Trends in Selective Hydrogen Peroxide Production on Transition Metal Surfaces from First Principles
DOE Office of Scientific and Technical Information (OSTI.GOV)
Rankin, Rees B.; Greeley, Jeffrey P.
2012-10-19
We present a comprehensive, Density Functional Theory-based analysis of the direct synthesis of hydrogen peroxide, H2O2, on twelve transition metal surfaces. We determine the full thermodynamics and selected kinetics of the reaction network on these metals, and we analyze these energetics with simple, microkinetically motivated rate theories to assess the activity and selectivity of hydrogen peroxide production on the surfaces of interest. By further exploiting Brønsted-Evans-Polanyi relationships and scaling relationships between the binding energies of different adsorbates, we express the results in the form of a two dimensional contour volcano plot, with the activity and selectivity being determined as functionsmore » of two independent descriptors, the atomic hydrogen and oxygen adsorption free energies. We identify both a region of maximum predicted catalytic activity, which is near Pt and Pd in descriptor space, and a region of selective hydrogen peroxide production, which includes Au. The optimal catalysts represent a compromise between activity and selectivity and are predicted to fall approximately between Au and Pd in descriptor space, providing a compact explanation for the experimentally known performance of Au-Pd alloys for hydrogen peroxide synthesis, and suggesting a target for future computational screening efforts to identify improved direct hydrogen peroxide synthesis catalysts. Related methods of combining activity and selectivity analysis into a single volcano plot may be applicable to, and useful for, other aqueous phase heterogeneous catalytic reactions where selectivity is a key catalytic criterion.« less
Alizadeh, Taher; Zare, Mashaalah; Ganjali, Mohamad Reza; Norouzi, Parviz; Tavana, Babak
2010-01-15
A high selective voltammetric sensor for 2,4,6-trinitrotoluene (TNT) was introduced. TNT selective MIP and non-imprinted polymer (NIP) were synthesized and then used for carbon paste (CP) electrode preparation. The MIP, incorporated in the carbon paste electrode, functioned as selectively recognition element and pre-concentrator agent for TNT determination. The prepared electrode was used for TNT measurement by the three steps procedure, including analyte extraction in the electrode, electrode washing and electrochemical measurement of TNT. The MIP-CP electrode showed very high recognition ability in comparison to NIP-CP. It was shown that electrode washing after TNT extraction led to enhanced selectivity. The response of square wave voltammetry for TNT determination by proposed electrode was higher than that of differential pulse voltammetry. Some parameters affecting sensor response were optimized and then a calibration curve plotted. A dynamic linear range of 5x10(-9) to 1x10(-6) mol l(-1) was obtained. The detection limit of the sensor was calculated equal to 1.5x10(-9) mol l(-1). This sensor was used successfully for TNT determination in different water and soil samples. Copyright 2009 Elsevier B.V. All rights reserved.
Tan, Lei; He, Rong; Li, Yongxian; Liang, Yong; Li, He; Tang, Youwen
2016-08-12
α-Amanitin and β-amanitin are the main toxins of mushroom poisoning. The application of traditional non-selective adsorbents is not satisfactory in clinical treatment of amanita mushroom poisoning due to lack of specificity adsorption capability of these adsorbents toward amanitin toxins. In the current work, we introduce a novel molecularly imprinted biomimetic adsorbent based on a ligand specificity determinant through surface imprinted strategy. Owing to the expensive price of the amanitin sources, we selected a typical common moiety of α, β-amanitin as specificity determinant to synthesize a template necessary for the preparation of molecularly imprinted polymers (MIPs). Computer simulation was used to initially select acidic methacrylic acid (MAA) and basic 4-vinyl pyridine (4-VP) together as functional monomers. The experiments further demonstrated that the synergistic interaction of MAA and 4-VP played a primary role in the recognition of α, β-amanitin by MIPs. By means of batch and packed-bed column experiment and the hemocompatibility evaluation, the resultant biomimetic adsorbent has been proved to be capable of selectively removing α, β-amanitin and possess good hemocompatibility. This novel adsorbent has great potential to find application in human plasma purification. Copyright © 2016 Elsevier B.V. All rights reserved.
He, Maofang; Wang, Chaozhan; Wei, Yinmao
2016-01-15
In this paper, iminodiacetic acid-Cu(II) functionalized Fe3O4@SiO2 magnetic nanoparticles were prepared and used as new adsorbents for magnetic solid phase extraction (MSPE) of six monoamine neurotransmitters (MNTs) from rabbit plasma. The selective enrichment of MNTs at pH 5.0 was motivated by the specific coordination interaction between amino groups of MNTs and the immobilized Cu(II). The employed weak acidic extraction condition avoided the oxidation of MNTs, and thus facilitated operation and ensured higher recoveries. Under optimal conditions, the recoveries of six MNTs from rabbit plasma were in the range of 83.9-109.4%, with RSD of 2.0-10.0%. When coupled the Cu(II) immobilized MSPE with high-performance liquid chromatography-fluorescence detection, the method exhibited relatively lower detection limits than the previously reported methods, and the method was successfully used to determine the endogenous MNTs in rabbit plasma. The proposed method has potential application for the determination of MNTs in biological samples. Also, the utilization of coordination interaction to improve the selectivity might open another way to selectively enrich small alkaloids from complex samples. Copyright © 2015 Elsevier B.V. All rights reserved.
Moreno-Opo, Rubén; Fernández-Olalla, Mariana; Margalida, Antoni; Arredondo, Ángel; Guil, Francisco
2012-01-01
The application of scientific-based conservation measures requires that sampling methodologies in studies modelling similar ecological aspects produce comparable results making easier their interpretation. We aimed to show how the choice of different methodological and ecological approaches can affect conclusions in nest-site selection studies along different Palearctic meta-populations of an indicator species. First, a multivariate analysis of the variables affecting nest-site selection in a breeding colony of cinereous vulture (Aegypius monachus) in central Spain was performed. Then, a meta-analysis was applied to establish how methodological and habitat-type factors determine differences and similarities in the results obtained by previous studies that have modelled the forest breeding habitat of the species. Our results revealed patterns in nesting-habitat modelling by the cinereous vulture throughout its whole range: steep and south-facing slopes, great cover of large trees and distance to human activities were generally selected. The ratio and situation of the studied plots (nests/random), the use of plots vs. polygons as sampling units and the number of years of data set determined the variability explained by the model. Moreover, a greater size of the breeding colony implied that ecological and geomorphological variables at landscape level were more influential. Additionally, human activities affected in greater proportion to colonies situated in Mediterranean forests. For the first time, a meta-analysis regarding the factors determining nest-site selection heterogeneity for a single species at broad scale was achieved. It is essential to homogenize and coordinate experimental design in modelling the selection of species' ecological requirements in order to avoid that differences in results among studies would be due to methodological heterogeneity. This would optimize best conservation and management practices for habitats and species in a global context. PMID:22413023
DETERMINANTS OF SPECIALTY CHOICE OF RESIDENT DOCTORS; CASE STUDY--AMONG RESIDENT DOCTORS IN NIGERIA.
Osuoji, Roland I; Adebanji, Atinuke; Abdulsalam, Moruf A; Oludara, Mobolaji A; Abolarinwa, Abimbola A
2015-01-01
This study examined medical specialty selection by Nigerian resident doctors using a marketing research approach to determine the selection criteria and the role of perceptions, expected remuneration, and job placement prospects of various specialties in the selection process. Data were from the Community of residents from April 2014 to July 2014. The cohort included 200 residents, but only 171 had complete information. Data were obtained from a cross section of resident doctors in the Lagos State University Teaching Hospital and at the 2014 Ordinary General Meeting of the National Association of Resident Doctors(NARD) where representatives from over 50 Teaching hospitals in Nigeria attended. Using a client behaviour model as a framework, a tripartite questionnaire was designed and administered to residents to deduce information on their knowledge about and interests in various specialties, their opinions of sixteen specialties, and the criteria they used in specialty selection. A total of 171 (85.5%) questionnaires were returned. ln many instances, consistency between selection criteria and perceptions of a specialty were accompanied by interest in pursuing the specialty. Job security, job availability on completion of programme, duration of training and qualifying examinations were highly correlated with p value < 0.05. Results of the Principal Component Analysis show two components (with Eigen values greater than one) explaining 65.3% of the total variance. The first component had placement and training and practice related variables loaded on it while the second component was loaded with job security and financial remuneration related variables. Using marketing research concepts for medical specialty selection (Weissmanet al 2012) stipulates that choice of speciality is influenced by criteria and perception. This study shows that job security expected financial remuneration, and examination requirements for qualification are major determinants of the choice of speciality for residents.
NASA Astrophysics Data System (ADS)
Deshpande, Amruta J.; Hughes, John P.; Wittman, David
2017-04-01
We continue the study of the first sample of shear-selected clusters from the initial 8.6 square degrees of the Deep Lens Survey (DLS); a sample with well-defined selection criteria corresponding to the highest ranked shear peaks in the survey area. We aim to characterize the weak lensing selection by examining the sample’s X-ray properties. There are multiple X-ray clusters associated with nearly all the shear peaks: 14 X-ray clusters corresponding to seven DLS shear peaks. An additional three X-ray clusters cannot be definitively associated with shear peaks, mainly due to large positional offsets between the X-ray centroid and the shear peak. Here we report on the XMM-Newton properties of the 17 X-ray clusters. The X-ray clusters display a wide range of luminosities and temperatures; the L X -T X relation we determine for the shear-associated X-ray clusters is consistent with X-ray cluster samples selected without regard to dynamical state, while it is inconsistent with self-similarity. For a subset of the sample, we measure X-ray masses using temperature as a proxy, and compare to weak lensing masses determined by the DLS team. The resulting mass comparison is consistent with equality. The X-ray and weak lensing masses show considerable intrinsic scatter (˜48%), which is consistent with X-ray selected samples when their X-ray and weak lensing masses are independently determined. Some of the data presented herein were obtained at the W.M. Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology, the University of California, and the National Aeronautics and Space Administration. The Observatory was made possible by the generous financial support of the W. M. Keck Foundation.
Corcóstegui, Reyes; Labeaga, Luis; Innerárity, Ana; Berisa, Agustin; Orjales, Aurelio
2005-01-01
This study aimed to establish the receptor selectivity and antihistaminic activity of bilastine, a new selective antihistamine receptor antagonist. In vitro experiments were conducted using a receptor binding screening panel and guinea-pig and rat tissues. Antihistaminic activity was determined using H1 receptor binding studies and in vitro H1 antagonism studies conducted in guinea-pig tissues and human cell lines. Receptor selectivity was established using a receptor binding screening panel and a receptor antagonism screening conducted in guinea-pig, rat and rabbit tissues. Inhibition of inflammatory mediators was determined through the Schultz-Dale reaction in sensitised guinea-pig ileum. Bilastine binds to histamine H1-receptors as indicated by its displacement of [3H]-pyrilamine from H1-receptors expressed in guinea-pig cerebellum and human embryonic kidney (HEK) cell lines. The studies conducted on guinea-pig smooth muscle demonstrated the capability of bilastine to antagonise H1-receptors. Bilastine is selective for histamine H1-receptors as shown in receptor-binding screening conducted to determine the binding capacity of bilastine to 30 different receptors. The specificity of its H1-receptor antagonistic activity was also demonstrated in a series of in vitro experiments conducted on guinea-pig and rat tissues. The results of these studies confirmed the lack of significant antagonism against serotonin, bradykinin, leukotriene D4, calcium, muscarinic M3-receptors, alpha1-adrenoceptors, beta2-adrenoceptors, and H2- and H3-receptors. The results of the in vitro Schultz-Dale reaction demonstrated that bilastine also has anti-inflammatory activity. These preclinical studies provide evidence that bilastine has H1- antihistamine activity, with high specificity for H1-receptors, and poor or no affinity for other receptors. Bilastine has also been shown to have anti-inflammatory properties.
Topcu, Cihan
2016-12-01
A novel polyvinyl chloride membrane chlorate (ClO 3 - ) selective electrode based on modified smectite was developed for the direct determination of chlorate ions and the potentiometric performance characteristics of its were examined. The best selectivity and sensitivity for chlorate ions were obtained for the electrode membrane containing ionophore/polyvinylchloride/o-nitrophenyloctylether in composition of 12/28/60 (w/w%). The proposed electrode showed a Nernstian response toward chlorate ions at pH=7 in the concentration range of 1×10 -7 -1×10 -1 M and the limit of detection was calculated as 9×10 -8 M from the constructed response plot. The linear slope of the electrode was -61±1mVdecade -1 for chlorate activity in the mentioned linear working range. The selectivity coefficients were calculated according to both the matched potential method and the separate solution method. The calculated selectivity coefficients showed that the electrode performed excellent selectivity for chlorate ions. The potentiometric response of electrode toward chlorate ions was found to be highly reproducible. The electrode potential was stable between pH=4-10 and it had a dynamic response time of <5s. The potentiometric behavior of the electrode in partial non-aqueous medium was also investigated and the obtained results (up to 5% (v/v) alcohol) were satisfactory. The proposed electrode was used during 15 weeks without any significant change in its potential response. Additionally, the electrode was very useful in water analysis studies such as dam water, river water, tap water, and swimming pool water where the direct determination of chlorate ions was required. Copyright © 2016 Elsevier B.V. All rights reserved.
Kernel learning at the first level of inference.
Cawley, Gavin C; Talbot, Nicola L C
2014-05-01
Kernel learning methods, whether Bayesian or frequentist, typically involve multiple levels of inference, with the coefficients of the kernel expansion being determined at the first level and the kernel and regularisation parameters carefully tuned at the second level, a process known as model selection. Model selection for kernel machines is commonly performed via optimisation of a suitable model selection criterion, often based on cross-validation or theoretical performance bounds. However, if there are a large number of kernel parameters, as for instance in the case of automatic relevance determination (ARD), there is a substantial risk of over-fitting the model selection criterion, resulting in poor generalisation performance. In this paper we investigate the possibility of learning the kernel, for the Least-Squares Support Vector Machine (LS-SVM) classifier, at the first level of inference, i.e. parameter optimisation. The kernel parameters and the coefficients of the kernel expansion are jointly optimised at the first level of inference, minimising a training criterion with an additional regularisation term acting on the kernel parameters. The key advantage of this approach is that the values of only two regularisation parameters need be determined in model selection, substantially alleviating the problem of over-fitting the model selection criterion. The benefits of this approach are demonstrated using a suite of synthetic and real-world binary classification benchmark problems, where kernel learning at the first level of inference is shown to be statistically superior to the conventional approach, improves on our previous work (Cawley and Talbot, 2007) and is competitive with Multiple Kernel Learning approaches, but with reduced computational expense. Copyright © 2014 Elsevier Ltd. All rights reserved.
Pal, Jayanta Kumar; Ray, Shubhra Sankar; Pal, Sankar K
2017-10-01
MicroRNAs (miRNA) are one of the important regulators of cell division and also responsible for cancer development. Among the discovered miRNAs, not all are important for cancer detection. In this regard a fuzzy mutual information (FMI) based grouping and miRNA selection method (FMIGS) is developed to identify the miRNAs responsible for a particular cancer. First, the miRNAs are ranked and divided into several groups. Then the most important group is selected among the generated groups. Both the steps viz., ranking of miRNAs and selection of the most relevant group of miRNAs, are performed using FMI. Here the number of groups is automatically determined by the grouping method. After the selection process, redundant miRNAs are removed from the selected set of miRNAs as per user's necessity. In a part of the investigation we proposed a FMI based particle swarm optimization (PSO) method for selecting relevant miRNAs, where FMI is used as a fitness function to determine the fitness of the particles. The effectiveness of FMIGS and FMI based PSO is tested on five data sets and their efficiency in selecting relevant miRNAs are demonstrated. The superior performance of FMIGS to some existing methods are established and the biological significance of the selected miRNAs is observed by the findings of the biological investigation and publicly available pathway analysis tools. The source code related to our investigation is available at http://www.jayanta.droppages.com/FMIGS.html. Copyright © 2017 Elsevier Ltd. All rights reserved.
Bandiera, Glen; Abrahams, Caroline; Ruetalo, Mariela; Hanson, Mark D; Nickell, Leslie; Spadafora, Salvatore
2015-12-01
Medical education institutions have a social mandate to produce a diverse physician workforce that meets the public's needs. Recent reports have framed the admission process outcome of undergraduate and postgraduate medical education (UGME and PGME) programs as a key determinant of the collective contributions graduating cohorts will make to society, creating a sense of urgency around the issue of who gets accepted. The need for evidence-informed residency application and selection processes is growing because of the increasing size and diversity of the applicant pool and the need for equity, fairness, social accountability, and health human resource planning. The selection literature, however, is dominated by a UGME focus and emphasizes determination of desirable qualities of future physicians and selection instrument reliability and validity. Gaps remain regarding PGME selection, particularly the creation of specialty-specific selection criteria, suitable outcome measures, and reliable selection systems.In this Perspective, the authors describe the University of Toronto's centralized approach to defining system-level best practices for residency application and selection. Over the 2012-2013 academic year, the Best Practices in Application and Selection working group reviewed relevant literature and reports, consulted content experts, surveyed local practices, and conducted iterative stakeholder consultations on draft recommendations. Strong agreement arose around the resulting 13 principles and 24 best practices, which had either empirical support or face validity. These recommendations, which are shared in this article, have been adopted by the university's PGME advisory committee and will inform a national initiative to improve trainees' transition from UGME to PGME in Canada.
Wardak, Cecylia; Grabarczyk, Malgorzata
2016-08-02
A simple, fast and cheap method for monitoring copper and nitrate in drinking water and food products using newly developed solid contact ion-selective electrodes is proposed. Determination of copper and nitrate was performed by application of multiple standard additions technique. The reliability of the obtained results was assessed by comparing them using the anodic stripping voltammetry or spectrophotometry for the same samples. In each case, satisfactory agreement of the results was obtained, which confirms the analytical usefulness of the constructed electrodes.
Millions of missing girls: from fetal sexing to high technology sex selection in India.
George, Sabu M
2006-07-01
The morality and acceptability of using prenatal diagnosis for sex selection is being extensively debated around the world as advances in assisted reproductive technologies (ART) and embryology have enabled selective implantation of embryos of the desired sex (George and Dahiya, 1998; Savulescu, 1999; Raphael, 2002; Harris, 2005; Robertson, 2005; Snider, 2005). Sophisticated methods of separation of semen, originally developed for cattle breeding, are being used for human sex selection. Recently, non-invasive methods of fetal sex determination in the first trimester (from 6 weeks) of pregnancy have also emerged (Hahn and Chitty, 2005). Market forces that promote sex selection along with libertarian ideologues have assisted in blurring the ethical limits (Paul, 2001; President's Council on Bioethics, 2003). The widespread misuse of sex selection for eliminating girls before birth in India and among the Indian diaspora needs to be brought into the global 'intellectual discourse'. It is imperative that Western ethicists recognize the genocidal nature of sex selection taking place in certain Asian countries. Even if they believe that these trends will not affect mainstream Western societies, the promotion or tolerance of sex selection amounts to a 'crime of silence' against this ongoing genocide in China and India. I have been concerned with issues of the girl child in India for over two decades and sex selection among Asian Indians in North America (George et al., 1992; George et al., 1993; George and Dahiya, 1998). This article examines the missing millions of girls, but will not consider the 1980s campaign against fetal sex determination, Indian feminists' recognition of sex selection as violence against women (unlike several Western feminists, Moazam, 2004), or the Government's response to regulate prenatal diagnostic techniques in 1994 (George and Dahiya, 1998; George, 2002). Copyright 2006 John Wiley & Sons, Ltd.
Hou, Sheng T; Dove, Mike; Anderson, Erica; Zhang, Jiangbing; MacKenzie, C Roger
2004-09-30
Targeting of postmitotic neurons selectively for gene delivery poses a challenge. One way to achieve such a selective targeting is to link the gene delivery vector with small ligand-binding polypeptides which have selective affinity to intact neurons. In order to identify such novel neuron selective polypeptides, we screened a phage-display library displaying random 12-mer polypeptides and subtractively bio-panned for clones having selectivity towards cultured mouse cerebellar granule neurons. The selected phage clones were amplified and sequenced. Affinities of these clones to neurons were determined by the visible presence or absence of fluorescence of phage particles as detected by immunocytochemistry using an antibody to M-13 phage. This affinity was further qualified by how much phage was bound, and where in or on the cell it tended to accumulate. The selectivity of binding to neurons was determined by the negative binding of these clones to several cultured non-neuronal cells, including, primary glial cells, NT2 cells, human embryonic kidney 293 cells, neuroblastoma cells, and mouse 3T3 cells. Among the 46 clones that we have sequenced and characterized, four clones appeared to have excellent selectivity in binding to neurons. Homology comparison of these polypeptides revealed that three of them contained a consensus D(E)-W(F)-I(N)-D-W motif. This motif was also present in the Bdm1 gene product which was predominantly expressed in postnatal brains. Further characterizations of these polypeptides are required to reveal the utilities of these peptides to function as an effective linker to facilitate gene transfer selectively to neurons.
Bjerke, Benjamin T; Cheung, Zoe B; Shifflett, Grant D; Iyer, Sravisht; Derman, Peter B; Cunningham, Matthew E
2015-10-01
Shoulder balance for adolescent idiopathic scoliosis (AIS) patients is associated with patient satisfaction and self-image. However, few validated systems exist for selecting the upper instrumented vertebra (UIV) post-surgical shoulder balance. The purpose is to examine the existing UIV selection criteria and correlate with post-surgical shoulder balance in AIS patients. Patients who underwent spinal fusion at age 10-18 years for AIS over a 6-year period were reviewed. All patients with a minimum of 1-year radiographic follow-up were included. Imbalance was determined to be radiographic shoulder height |RSH| ≥ 15 mm at latest follow-up. Three UIV selection methods were considered: Lenke, Ilharreborde, and Trobisch. A recommended UIV was determined using each method from pre-surgical radiographs. The recommended UIV for each method was compared to the actual UIV instrumented for all three methods; concordance between these levels was defined as "Correct" UIV selection, and discordance was defined as "Incorrect" selection. One hundred seventy-one patients were included with 2.3 ± 1.1 year follow-up. For all methods, "Correct" UIV selection resulted in more shoulder imbalance than "Incorrect" UIV selection. Overall shoulder imbalance incidence was improved from 31.0% (53/171) to 15.2% (26/171). New shoulder imbalance incidence for patients with previously level shoulders was 8.8%. We could not identify a set of UIV selection criteria that accurately predicted post-surgical shoulder balance. Further validated measures are needed in this area. The complexity of proximal thoracic curve correction is underscored in a case example, where shoulder imbalance occurred despite "Correct" UIV selection by all methods.
SPECTROPHOTOMETRIC DETERMINATION OF CALCIUM WITH GLYOXAL BIS (2-HYDROXY- ANIL)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Florence, T.M.; Morgan, J.
1961-03-01
A selective method is described for the spectrophotometric determination of calcium using glyoxal bis(2hydroxy-anil) as the chromogenic agent. A comprehensive study of interferences and reagent variables was made. (auth)
40 CFR 60.145a - Compliance provisions.
Code of Federal Regulations, 2014 CFR
2014-07-01
... data sets shall be determined accordingly. (e) To determine compliance with § 60.142a(a)(1), select the data sets yielding the highest and second highest 3-minute average opacities for each steel production...
40 CFR 60.145a - Compliance provisions.
Code of Federal Regulations, 2010 CFR
2010-07-01
... data sets shall be determined accordingly. (e) To determine compliance with § 60.142a(a)(1), select the data sets yielding the highest and second highest 3-minute average opacities for each steel production...
40 CFR 60.145a - Compliance provisions.
Code of Federal Regulations, 2012 CFR
2012-07-01
... data sets shall be determined accordingly. (e) To determine compliance with § 60.142a(a)(1), select the data sets yielding the highest and second highest 3-minute average opacities for each steel production...
40 CFR 60.145a - Compliance provisions.
Code of Federal Regulations, 2013 CFR
2013-07-01
... data sets shall be determined accordingly. (e) To determine compliance with § 60.142a(a)(1), select the data sets yielding the highest and second highest 3-minute average opacities for each steel production...
40 CFR 60.145a - Compliance provisions.
Code of Federal Regulations, 2011 CFR
2011-07-01
... data sets shall be determined accordingly. (e) To determine compliance with § 60.142a(a)(1), select the data sets yielding the highest and second highest 3-minute average opacities for each steel production...
ION COMPOSITION ELUCIDATION (ICE)
Ion Composition Elucidation (ICE) utilizes selected ion recording with a double focusing mass spectrometer to simultaneously determine exact masses and relative isotopic abundances from mass peak profiles. These can be determined more accurately and at higher sensitivity ...
Aptamer-based potentiometric measurements of proteins using ion-selective microelectrodes.
Numnuam, Apon; Chumbimuni-Torres, Karin Y; Xiang, Yun; Bash, Ralph; Thavarungkul, Panote; Kanatharana, Proespichaya; Pretsch, Ernö; Wang, Joseph; Bakker, Eric
2008-02-01
We here report on the first example of an aptamer-based potentiometric sandwich assay of proteins. The measurements are based on CdS quantum dot labels of the secondary aptamer, which were determined with a novel solid-contact Cd2+-selective polymer membrane electrode after dissolution with hydrogen peroxide. The electrode exhibited cadmium ion detection limits of 100 pM in 100 mL samples and of 1 nM in 200 microL microwells, using a calcium-selective electrode as a pseudoreference electrode. As a prototype example, thrombin was measured in 200 microL samples with a lower detection limit of 0.14 nM corresponding to 28 fmol of analyte. The results show great promise for the potentiometric determination of proteins at very low concentrations in microliter samples.
The impact of dispersion on selective laser melting of titanium and niobium fine powders mixture
NASA Astrophysics Data System (ADS)
Razin, A.; Ovchinnikov, V.; Akhmetshin, R.; Krinitcyn, M.; Fedorov, V.; Akhmetshina, V.
2016-11-01
This paper is dedicated to the study of selective laser melting process of metal powders. Experiments were performed in the Research Center Modern Manufacturing Technologies of TPU with the fine powders of titanium and niobium. The research was carried out on 3D laser printer designed at TPU. In the framework of experiments aimed at determining possibilities of obtaining niobium-titanium alloy by SLS (selective laser sintering) there were studied the basic processes of laser melting and their effect on the quality of final samples and products. We determined operation modes of 3D printers which allow obtaining high quality of printed sample surface. The research results show that rigid requirements related to powder dispersiveness and proportions are needed to achieve better quality of products.
The use of grey literature in health sciences: a preliminary survey.
Alberani, V; De Castro Pietrangeli, P; Mazza, A M
1990-01-01
The paper describes some initiatives in the field of grey literature (GL) and the activities, from 1985, of the Italian Library Association Study Group. The major categories of GL are defined; a survey that evaluates the use of GL by end users in the health sciences is described. References in selected periodicals and databases have been analyzed for the years 1987-1988 to determine the number of articles citing GL, the number of GL citations found in selected periodicals, the various types of GL found, and the number of technical reports cited and their country of origin and intergovernmental issuing organization. Selected databases were also searched to determine the presence of GL during those same years. The paper presents the first results obtained. Images PMID:2224298
de Almeida, Valber Elias; de Araújo Gomes, Adriano; de Sousa Fernandes, David Douglas; Goicoechea, Héctor Casimiro; Galvão, Roberto Kawakami Harrop; Araújo, Mario Cesar Ugulino
2018-05-01
This paper proposes a new variable selection method for nonlinear multivariate calibration, combining the Successive Projections Algorithm for interval selection (iSPA) with the Kernel Partial Least Squares (Kernel-PLS) modelling technique. The proposed iSPA-Kernel-PLS algorithm is employed in a case study involving a Vis-NIR spectrometric dataset with complex nonlinear features. The analytical problem consists of determining Brix and sucrose content in samples from a sugar production system, on the basis of transflectance spectra. As compared to full-spectrum Kernel-PLS, the iSPA-Kernel-PLS models involve a smaller number of variables and display statistically significant superiority in terms of accuracy and/or bias in the predictions. Published by Elsevier B.V.
Substrate Control in Stereoselective Lanthionine Biosynthesis
Tang, Weixin; Jiménez-Osés, Gonzalo; Houk, K. N.; van der Donk, Wilfred A.
2014-01-01
Enzymes are typically highly stereoselective catalysts that enforce a reactive conformation on their native substrates. We report here a rare example where the substrate controls the stereoselectivity of an enzyme-catalyzed Michael-type addition during the biosynthesis of lanthipeptides. These natural products contain thioether crosslinks formed by cysteine attack on dehydrated Ser and Thr residues. We demonstrate that several lanthionine synthetases catalyze highly selective anti additions in which the substrate (and not the enzyme) determines whether the addition occurs from the Re or Si face. A single point mutation in the peptide substrate completely inverted the stereochemical outcome of the enzymatic modification. Quantum mechanical calculations reproduced the experimentally observed selectivity and suggest that conformational restraints imposed by the amino acid sequence on the transition states determine the face selectivity of the Michael-type cyclization. PMID:25515891
Method for photon activation positron annihilation analysis
Akers, Douglas W.
2006-06-06
A non-destructive testing method comprises providing a specimen having at least one positron emitter therein; determining a threshold energy for activating the positron emitter; and determining whether a half-life of the positron emitter is less than a selected half-life. If the half-life of the positron emitter is greater than or equal to the selected half-life, then activating the positron emitter by bombarding the specimen with photons having energies greater than the threshold energy and detecting gamma rays produced by annihilation of positrons in the specimen. If the half-life of the positron emitter is less then the selected half-life, then alternately activating the positron emitter by bombarding the specimen with photons having energies greater then the threshold energy and detecting gamma rays produced by positron annihilation within the specimen.
Institutional Efficiency in Selected Universities in Uganda
ERIC Educational Resources Information Center
Amina, Nakimuli; Turyahebwa, Abanis
2015-01-01
Universities are accountable This study looked into Institutional Efficiency in selected Universities in Central Uganda. The study was guided by the following objectives; Determine the level of institutional efficiency of the universities in terms of educational efficiency; research efficiency and community service efficiency. The study employed…
Main-channel slopes of selected streams in Iowa for estimation of flood-frequency discharges.
DOT National Transportation Integrated Search
2003-01-01
This report describes a statewide study : conducted to develop main-channel slope (MCS) : curves for 138 selected streams in Iowa with : drainage areas greater than 100 square miles. : MCS values determined from the curves can be : used in regression...
Selecting Telephone Systems for a School District.
ERIC Educational Resources Information Center
Paddock, Steve
1989-01-01
A tried and tested formula for selecting the right telephone system includes the following elements: determining telephone system needs, considering future growth, using written proposals to make comparisons, and shopping for quality products with excellent references. Flagstaff (Arizona) Uified School District's experience is used to illustrate…
SELECTING AND EVALUATING NATIVE PLANTS FOR REGION-SPECIFIC PHYTOTOXICITY TESTING
In this study, we evaluated methodology to determine risks to terrestrial native plant species from potential herbicide drift, focusing on 1) selection of native species for testing, 2) growth of these species, and 3) variability in herbicide response among native species and com...
Simulating natural selection in landscape genetics
E. L. Landguth; S. A. Cushman; N. Johnson
2012-01-01
Linking landscape effects to key evolutionary processes through individual organism movement and natural selection is essential to provide a foundation for evolutionary landscape genetics. Of particular importance is determining how spatially- explicit, individual-based models differ from classic population genetics and evolutionary ecology models based on ideal...
Mechanical shear and tensile characteristics of selected biomass stems
USDA-ARS?s Scientific Manuscript database
Mechanical characteristics (stress and energy of tensile and shear modes) of selected biomass stems, such as big bluestem, bromegrass, and Barlow wheat were determined. A high capacity MTI-100K universal testing machine attached with standard tensile clamps and designed fabricated double-shear devic...
Politics of Textbook Selection.
ERIC Educational Resources Information Center
Keith, Sherry
The process of determining textbook content and selecting textbooks for classroom use in public schools throughout America is highly political and raises many fundamental questions about the relationship between education as a social enterprise and other aspects of society--economic, ideological, political, and legal. This study focuses on three…
Variable Effect during Polymerization
ERIC Educational Resources Information Center
Lunsford, S. K.
2005-01-01
An experiment performing the polymerization of 3-methylthiophene(P-3MT) onto the conditions for the selective electrode to determine the catechol by using cyclic voltammetry was performed. The P-3MT formed under optimized conditions improved electrochemical reversibility, selectivity and reproducibility for the detection of the catechol.
A Theoretical Approach for Selecting Elementary School Environmental Variables.
ERIC Educational Resources Information Center
Sinclair, Robert L.
To determine specific environmental variables of the elementary school is the purpose of this study. Stable characteristics of intelligence and achievement were selected because they were considered useful for generating salient environmental counterparts likely to exist in elementary institutions. Achievement motivation, language development, and…
USDA-ARS?s Scientific Manuscript database
A digestibility trial with channel catfish Ictalurus punctatus was conducted to determine apparent availability coefficients (AACs) of phosphorus for selected common feedstuffs: soybean meal, cottonseed meal, wheat middlings, corn gluten feed (CGF), and corn distillers dried grains with solubles (DD...
ERIC Educational Resources Information Center
Butala, Steven J.; Zarrabi, Kaveh
1995-01-01
Describes a student research project that determined concentrations of lead in water drawn from selected drinking fountains and in selected soil samples on the campus of the University of Nevada, Las Vegas. (18 references) (DDR)
Operational Site Selection for Unmanned Aircraft
2011-06-01
eliminate unsuitable areas, the Op Site Selection process must first consider landcover , terrain, and specifications for one or more UAS platforms...areas, the OSS process must first consider landcover , terrain, and specifi- cations for one or more UAS platforms. To select the most optimal sites, the...by landcover , ERDC/CERL TR-11-16 2 soil type, slope, and aspect. The individual terrain units are pre- determined and delineated by a separate
Process of labeling specific chromosomes using recombinant repetitive DNA
Moyzis, R.K.; Meyne, J.
1988-02-12
Chromosome preferential nucleotide sequences are first determined from a library of recombinant DNA clones having families of repetitive sequences. Library clones are identified with a low homology with a sequence of repetitive DNA families to which the first clones respectively belong and variant sequences are then identified by selecting clones having a pattern of hybridization with genomic DNA dissimilar to the hybridization pattern shown by the respective families. In another embodiment, variant sequences are selected from a sequence of a known repetitive DNA family. The selected variant sequence is classified as chromosome specific, chromosome preferential, or chromosome nonspecific. Sequences which are classified as chromosome preferential are further sequenced and regions are identified having a low homology with other regions of the chromosome preferential sequence or with known sequences of other family members and consensus sequences of the repetitive DNA families for the chromosome preferential sequences. The selected low homology regions are then hybridized with chromosomes to determine those low homology regions hybridized with a specific chromosome under normal stringency conditions.
A new model of selection in women's handball.
Srhoj, Vatromir; Rogulj, Nenad; Zagorac, Nebojsa; Katić, Ratko
2006-09-01
The aim of the study was to assess the basic motor abilities that determine top performance in women's handball, and to identify test panel for primary selection at handball school. The study included 155 female attendants of the Split Handball School, mean age 12.5 years. Differences in the basic motor abilities between the subjects that developed into elite handball players after 7-year training process and those that abandoned handball for being unable to meet the competition criteria were evaluated by use of discriminative analysis. The former were found to have also been superior initially in all variables analyzed, and in arm coordination, overall body coordination, throw and jump explosive strength, arm movement frequency and repetitive trunk strength in particular. Motor superiority based on the abilities of coordination, explosive strength and speed determines performance in women's handball, qualifying these abilities as reliable selection criteria. Based on this study results, a new model of selection in women's handball, with fine arm coordination as the major limiting factor of performance, has been proposed.
Evolution of recombination rates in a multi-locus, haploid-selection, symmetric-viability model.
Chasnov, J R; Ye, Felix Xiaofeng
2013-02-01
A fast algorithm for computing multi-locus recombination is extended to include a recombination-modifier locus. This algorithm and a linear stability analysis is used to investigate the evolution of recombination rates in a multi-locus, haploid-selection, symmetric-viability model for which stable equilibria have recently been determined. When the starting equilibrium is symmetric with two selected loci, we show analytically that modifier alleles that reduce recombination always invade. When the starting equilibrium is monomorphic, and there is a fixed nonzero recombination rate between the modifier locus and the selected loci, we determine analytical conditions for which a modifier allele can invade. In particular, we show that a gap exists between the recombination rates of modifiers that can invade and the recombination rate that specifies the lower stability boundary of the monomorphic equilibrium. A numerical investigation shows that a similar gap exists in a weakened form when the starting equilibrium is fully polymorphic but asymmetric. Copyright © 2012 Elsevier Inc. All rights reserved.
Hunt, M R; Garmyn, A J; O'Quinn, T G; Corbin, C H; Legako, J F; Rathmann, R J; Brooks, J C; Miller, M F
2014-09-01
Consumer sensory analysis was conducted to determine differences in beef palatability between two quality grade categories [Upper 2/3 (Top) Choice and Select] and four muscles [longissimus lumborum (LL), gluteus medius (GM), serratus ventralis (SV), and semimembranosus (SM)]. Generally, tenderness, flavor, and overall liking scores were more desirable for Top Choice compared to Select, regardless of muscle. Consumers rated LL as more tender (P<0.05) than SV and SM, but similar to GM (P=0.52). Overall and flavor acceptability were similar (P>0.05) between LL, GM, and SV, regardless of quality grade. Consumer overall liking was most highly correlated with flavor liking (r=0.85). When tenderness was acceptable, flavor and juiciness played a major role in determining overall acceptability. Overall liking of GM and SV from Top Choice carcasses was superior to LL from Select carcasses and comparable to LL from Top Choice carcasses. Copyright © 2014 Elsevier Ltd. All rights reserved.
Optimization of Candidate Selection Using Naive Bayes: Case Study in Company X
NASA Astrophysics Data System (ADS)
Kadar, JA; Agustono, D.; Napitupulu, D.
2018-01-01
This research was conducted as a decision-making system, and an alternative solution to complete the candidate assessment for a particular position. The human resources (HR) section on company X is responsible and initiative in selecting candidates in accordance with the assessment of their superiors. Selection by using the method of filling out the manager’s assessment questionnaire on the candidate’s subordinate. Three (3) managers have been determined to assess the 11 candidates for subordinates. By using questionnaire of quality classification of human resources and formula naive bayes it will get result which finally grouped using criteria scale as final grouping. The HR department has also determined that what is received is that which meets criteria 5. The result is three (3) candidates who can be proposed as candidates for certain positions in company X, and have met all required calculations. Furthermore the candidate will be given to management as an alternative input data in the selection of candidates.
Diez, Alejandro; Powelson, John; Sundaram, Chandru P; Taber, Tim E; Mujtaba, Muhammad A; Yaqub, Muhammad S; Mishler, Dennis P; Goggins, William C; Sharfuddin, Asif A
2014-06-01
Living donor evaluation involves imaging to determine the choice of kidney for nephrectomy. Our aim was to study the diagnostic accuracy and correlation between CT-based volume measurements and split renal function (SRF) as measured by nuclear renography in potential living donors and its impact on kidney selection decision. We analyzed 190 CT-based volume measurements in healthy donors, of which 65 donors had a radionuclide study performed to determine SRF. There were no differences in demographics, anthropometric measurements, total volumes, eGFR, creatinine clearances between those who required a nuclear scan and those who did not. There was a significant correlation between CT-volume-measurement-based SRF and nuclear-scan-based SRF (Pearson coefficient r 0.59; p < 0.001). Furthermore, selective nuclear-based SRF allowed careful selection of donor nephrectomy, leaving the donor with the higher functioning kidney in most cases. There was also a significantly higher number of right-sided nephrectomies selected after nuclear-based SRF studies. CT-based volume measurements in living donor imaging have sufficient correlation with nuclear-based SRF. Selective use of nuclear-scan-based SRF allows careful selection for donor nephrectomy. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
JCoDA: a tool for detecting evolutionary selection.
Steinway, Steven N; Dannenfelser, Ruth; Laucius, Christopher D; Hayes, James E; Nayak, Sudhir
2010-05-27
The incorporation of annotated sequence information from multiple related species in commonly used databases (Ensembl, Flybase, Saccharomyces Genome Database, Wormbase, etc.) has increased dramatically over the last few years. This influx of information has provided a considerable amount of raw material for evaluation of evolutionary relationships. To aid in the process, we have developed JCoDA (Java Codon Delimited Alignment) as a simple-to-use visualization tool for the detection of site specific and regional positive/negative evolutionary selection amongst homologous coding sequences. JCoDA accepts user-inputted unaligned or pre-aligned coding sequences, performs a codon-delimited alignment using ClustalW, and determines the dN/dS calculations using PAML (Phylogenetic Analysis Using Maximum Likelihood, yn00 and codeml) in order to identify regions and sites under evolutionary selection. The JCoDA package includes a graphical interface for Phylip (Phylogeny Inference Package) to generate phylogenetic trees, manages formatting of all required file types, and streamlines passage of information between underlying programs. The raw data are output to user configurable graphs with sliding window options for straightforward visualization of pairwise or gene family comparisons. Additionally, codon-delimited alignments are output in a variety of common formats and all dN/dS calculations can be output in comma-separated value (CSV) format for downstream analysis. To illustrate the types of analyses that are facilitated by JCoDA, we have taken advantage of the well studied sex determination pathway in nematodes as well as the extensive sequence information available to identify genes under positive selection, examples of regional positive selection, and differences in selection based on the role of genes in the sex determination pathway. JCoDA is a configurable, open source, user-friendly visualization tool for performing evolutionary analysis on homologous coding sequences. JCoDA can be used to rapidly screen for genes and regions of genes under selection using PAML. It can be freely downloaded at http://www.tcnj.edu/~nayaklab/jcoda.
JCoDA: a tool for detecting evolutionary selection
2010-01-01
Background The incorporation of annotated sequence information from multiple related species in commonly used databases (Ensembl, Flybase, Saccharomyces Genome Database, Wormbase, etc.) has increased dramatically over the last few years. This influx of information has provided a considerable amount of raw material for evaluation of evolutionary relationships. To aid in the process, we have developed JCoDA (Java Codon Delimited Alignment) as a simple-to-use visualization tool for the detection of site specific and regional positive/negative evolutionary selection amongst homologous coding sequences. Results JCoDA accepts user-inputted unaligned or pre-aligned coding sequences, performs a codon-delimited alignment using ClustalW, and determines the dN/dS calculations using PAML (Phylogenetic Analysis Using Maximum Likelihood, yn00 and codeml) in order to identify regions and sites under evolutionary selection. The JCoDA package includes a graphical interface for Phylip (Phylogeny Inference Package) to generate phylogenetic trees, manages formatting of all required file types, and streamlines passage of information between underlying programs. The raw data are output to user configurable graphs with sliding window options for straightforward visualization of pairwise or gene family comparisons. Additionally, codon-delimited alignments are output in a variety of common formats and all dN/dS calculations can be output in comma-separated value (CSV) format for downstream analysis. To illustrate the types of analyses that are facilitated by JCoDA, we have taken advantage of the well studied sex determination pathway in nematodes as well as the extensive sequence information available to identify genes under positive selection, examples of regional positive selection, and differences in selection based on the role of genes in the sex determination pathway. Conclusions JCoDA is a configurable, open source, user-friendly visualization tool for performing evolutionary analysis on homologous coding sequences. JCoDA can be used to rapidly screen for genes and regions of genes under selection using PAML. It can be freely downloaded at http://www.tcnj.edu/~nayaklab/jcoda. PMID:20507581
Automatic peak selection by a Benjamini-Hochberg-based algorithm.
Abbas, Ahmed; Kong, Xin-Bing; Liu, Zhi; Jing, Bing-Yi; Gao, Xin
2013-01-01
A common issue in bioinformatics is that computational methods often generate a large number of predictions sorted according to certain confidence scores. A key problem is then determining how many predictions must be selected to include most of the true predictions while maintaining reasonably high precision. In nuclear magnetic resonance (NMR)-based protein structure determination, for instance, computational peak picking methods are becoming more and more common, although expert-knowledge remains the method of choice to determine how many peaks among thousands of candidate peaks should be taken into consideration to capture the true peaks. Here, we propose a Benjamini-Hochberg (B-H)-based approach that automatically selects the number of peaks. We formulate the peak selection problem as a multiple testing problem. Given a candidate peak list sorted by either volumes or intensities, we first convert the peaks into [Formula: see text]-values and then apply the B-H-based algorithm to automatically select the number of peaks. The proposed approach is tested on the state-of-the-art peak picking methods, including WaVPeak [1] and PICKY [2]. Compared with the traditional fixed number-based approach, our approach returns significantly more true peaks. For instance, by combining WaVPeak or PICKY with the proposed method, the missing peak rates are on average reduced by 20% and 26%, respectively, in a benchmark set of 32 spectra extracted from eight proteins. The consensus of the B-H-selected peaks from both WaVPeak and PICKY achieves 88% recall and 83% precision, which significantly outperforms each individual method and the consensus method without using the B-H algorithm. The proposed method can be used as a standard procedure for any peak picking method and straightforwardly applied to some other prediction selection problems in bioinformatics. The source code, documentation and example data of the proposed method is available at http://sfb.kaust.edu.sa/pages/software.aspx.
Automatic Peak Selection by a Benjamini-Hochberg-Based Algorithm
Abbas, Ahmed; Kong, Xin-Bing; Liu, Zhi; Jing, Bing-Yi; Gao, Xin
2013-01-01
A common issue in bioinformatics is that computational methods often generate a large number of predictions sorted according to certain confidence scores. A key problem is then determining how many predictions must be selected to include most of the true predictions while maintaining reasonably high precision. In nuclear magnetic resonance (NMR)-based protein structure determination, for instance, computational peak picking methods are becoming more and more common, although expert-knowledge remains the method of choice to determine how many peaks among thousands of candidate peaks should be taken into consideration to capture the true peaks. Here, we propose a Benjamini-Hochberg (B-H)-based approach that automatically selects the number of peaks. We formulate the peak selection problem as a multiple testing problem. Given a candidate peak list sorted by either volumes or intensities, we first convert the peaks into -values and then apply the B-H-based algorithm to automatically select the number of peaks. The proposed approach is tested on the state-of-the-art peak picking methods, including WaVPeak [1] and PICKY [2]. Compared with the traditional fixed number-based approach, our approach returns significantly more true peaks. For instance, by combining WaVPeak or PICKY with the proposed method, the missing peak rates are on average reduced by 20% and 26%, respectively, in a benchmark set of 32 spectra extracted from eight proteins. The consensus of the B-H-selected peaks from both WaVPeak and PICKY achieves 88% recall and 83% precision, which significantly outperforms each individual method and the consensus method without using the B-H algorithm. The proposed method can be used as a standard procedure for any peak picking method and straightforwardly applied to some other prediction selection problems in bioinformatics. The source code, documentation and example data of the proposed method is available at http://sfb.kaust.edu.sa/pages/software.aspx. PMID:23308147
NASA Astrophysics Data System (ADS)
Dikunets, M. A.; Appolonova, S. A.; Rodchenkov, G. M.
2009-04-01
This work presents a high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) procedure for selective and reliable screening of corticosteroids and diuretics in human urine. Sample preparation included the extraction, evaporation of the organic extract under nitrogen, and solution of the dry residue. The extract was analyzed by HPLC combined with tandem mass spectrometry using electro-spraying ionization at atmospheric pressure with negative ion recording. The mass spectra of all compounds were recorded, and the characteristic ions, retention times, and detection limits were determined. The procedure was validated by evaluating the degree of the matrix suppression of ionization, extraction of analytes from human biological liquid, and the selectivity and specificity of determination.
NASA Technical Reports Server (NTRS)
1981-01-01
A study was performed to determine the types of manned missions that will likely be performed in the late 1980's or early 1990's timeframe, to define MOTV configurations which satisfy these missions requirements, and to develop a program plan for its development. Twenty generic missions were originally defined for MOTV but, to simplify the selection process, five of these missions were selected as typical and used as Design Reference Missions. Systems and subsystems requirements were re-examined and sensitivity analyses performed to determine optimum point designs. Turnaround modes were considered to determine the most effective combination of ground based and spaced based activities. A preferred concept for the crew capsule and for the mission mode was developed.
Grimaldi, F.S.
1957-01-01
This paper presents a selective iodate separation of thorium from nitric acid medium containing d-tartaric acid and hydrogen peroxide. The catalytic decomposition of hydrogen peroxide is prevented by the use of 8quinolinol. A few micrograms of thorium are separated sufficiently clean from 30 mg. of such oxides as cerium, zirconium, titanium, niobium, tantalum, scandium, or iron with one iodate precipitation to allow an accurate determination of thorium with the thoronmesotartaric acid spectrophotometric method. The method is successful for the determination of 0.001% or more of thorium dioxide in silicate rocks and for 0.01% or more in black sand, monazite, thorite, thorianite, eschynite, euxenite, and zircon.
NASA Astrophysics Data System (ADS)
Sirait, Kamson; Tulus; Budhiarti Nababan, Erna
2017-12-01
Clustering methods that have high accuracy and time efficiency are necessary for the filtering process. One method that has been known and applied in clustering is K-Means Clustering. In its application, the determination of the begining value of the cluster center greatly affects the results of the K-Means algorithm. This research discusses the results of K-Means Clustering with starting centroid determination with a random and KD-Tree method. The initial determination of random centroid on the data set of 1000 student academic data to classify the potentially dropout has a sse value of 952972 for the quality variable and 232.48 for the GPA, whereas the initial centroid determination by KD-Tree has a sse value of 504302 for the quality variable and 214,37 for the GPA variable. The smaller sse values indicate that the result of K-Means Clustering with initial KD-Tree centroid selection have better accuracy than K-Means Clustering method with random initial centorid selection.
Path selection system simulation and evaluation for a Martian roving vehicle
NASA Technical Reports Server (NTRS)
Boheim, S. L.; Prudon, W. C.
1972-01-01
The simulation and evaluation of proposed path selection systems for an autonomous Martian roving vehicle was developed. The package incorporates a number of realistic features, such as the simulation of random effects due to vehicle bounce and sensor-reading uncertainty, to increase the reliability of the results. Qualitative and quantitative evaluation criteria were established. The performance of three different path selection systems was evaluated to determine the effectiveness of the simulation package, and to form some preliminary conclusions regarding the tradeoffs involved in a path selection system design.
The Determinants of Private and Government Sector Earnings in Russia
2000-11-01
private sector earnings in Russia compare to those in the still strong government sector. This paper estimates sectoral earnings equations for rural and urban men and women which control for: (1) Self-selection into the workforce; and (2) Self-selection into either the private or government sector, while allowing for simultaneity in the selection decisions. The selection controls are found to have a considerable effect on the estimated sectoral earnings differentials for all four sample groups. Earnings differentials are examined by age, education, and unobserved skill.
NASA Astrophysics Data System (ADS)
Stytsenko, V. D.; Mel'nikov, D. P.; Tkachenko, O. P.; Savel'eva, E. V.; Semenov, A. P.; Kustov, L. M.
2018-05-01
The selective hydrogenation of acetylene on Pd-Fe/Al2O3 catalysts prepared by decomposition of ferrocene on reduced Pd/Al2O3 was studied. The effect of the conditions of treatment of the Pd-ferrocene/ Al2O3 precursor on the catalyst activity and selectivity was investigated, and the optimum conditions were determined at which the Pd-Fe/Al2O3 catalyst has higher selectivity than Pd/Al2O3 without any loss of activity.
Sex selection: treating different cases differently.
Dickens, B M; Serour, G I; Cook, R J; Qiu, R-Z
2005-08-01
This paper contrasts ethical approaches to sex selection in countries where discrimination against women is pervasive, resulting in selection against girl children, and in countries where there is less general discrimination and couples do not prefer children of either sex. National sex ratio imbalances where discrimination against women is common have resulted in laws and policies, such as in India and China, to deter and prevent sex selection. Birth ratios of children can be affected by techniques of prenatal sex determination and abortion, preconception sex selection and discarding disfavored embryos, and prefertilization sperm sorting, when disfavored sperm remain unused. Incentives for son preference are reviewed, and laws and policies to prevent sex selection are explained. The elimination of social, economic and other discrimination against women is urged to redress sex selection against girl children. Where there is no general selection against girl children, sex selection can be allowed to assist families that want children of both sexes.
Tests of selection in pooled case-control data: an empirical study.
Udpa, Nitin; Zhou, Dan; Haddad, Gabriel G; Bafna, Vineet
2011-01-01
For smaller organisms with faster breeding cycles, artificial selection can be used to create sub-populations with different phenotypic traits. Genetic tests can be employed to identify the causal markers for the phenotypes, as a precursor to engineering strains with a combination of traits. Traditional approaches involve analyzing crosses of inbred strains to test for co-segregation with genetic markers. Here we take advantage of cheaper next generation sequencing techniques to identify genetic signatures of adaptation to the selection constraints. Obtaining individual sequencing data is often unrealistic due to cost and sample issues, so we focus on pooled genomic data. We explore a series of statistical tests for selection using pooled case (under selection) and control populations. The tests generally capture skews in the scaled frequency spectrum of alleles in a region, which are indicative of a selective sweep. Extensive simulations are used to show that these approaches work well for a wide range of population divergence times and strong selective pressures. Control vs control simulations are used to determine an empirical False Positive Rate, and regions under selection are determined using a 1% FPR level. We show that pooling does not have a significant impact on statistical power. The tests are also robust to reasonable variations in several different parameters, including window size, base-calling error rate, and sequencing coverage. We then demonstrate the viability (and the challenges) of one of these methods in two independent Drosophila populations (Drosophila melanogaster) bred under selection for hypoxia and accelerated development, respectively. Testing for extreme hypoxia tolerance showed clear signals of selection, pointing to loci that are important for hypoxia adaptation. Overall, we outline a strategy for finding regions under selection using pooled sequences, then devise optimal tests for that strategy. The approaches show promise for detecting selection, even several generations after fixation of the beneficial allele has occurred.
Sex determination: balancing selection in the honey bee.
Charlesworth, Deborah
2004-07-27
Sequences of alleles of the honey bee's primary sex-determining gene have extremely high diversity, with many amino acid variants, suggesting that different alleles of this gene have been maintained in populations for very long evolutionary times.
Perimeter Barrier Selection Guide
DOT National Transportation Integrated Search
1989-05-01
This document provides a methodology to determine the magnitude of the threat from attack vehicles to the perimeter of a facility. The threat is determined by the penetration tolerance and the maximum speed attainable. After the threat is defined thi...
Extraction photometric determination of yperite by phthaleins.
Halámek, E; Kobliha, Z
1999-01-01
Extraction spectrophotometric determination of sulfidic yperite, based on the reaction with four phthaleins, was developed. The method is technically simpler than the determination of yperites with reagent T-135 (alkaline-aqueous ethanolic thymolphthalein solution) because it does not require heating at 80 degrees C, cooling and acidification of the reaction mixture. Selection of the appropriate phthalein, and particularly optimization of the reagent composition and extraction of the coloured reaction product in chloroform, markedly increased the selectivity of the determination of yperites (HD, HN-3). The reaction is performed in a medium of increased polarity due to the low content of alcohol which enables the reaction to proceed at temperatures of 5-20 degrees C without any marked loss of sensitivity. Using (1)H and (13)C NMR spectroscopy, the reaction products of HD and o-cresolphthalein were identified and an ionic mechanism for the reaction of HD with phthaleins is suggested.
Ashagre, Mekonnen Abiyot; Masadome, Takashi
2018-01-01
A new microfluidic polymer chip with an embedded cationic surfactant (CS) ion-selective optode (CS-optode) as a detector of flow-injection analysis (FIA) for the determination of CSs was developed. The optode sensing membrane is based on a poly(vinyl chloride) membrane plasticized with 2-nitrophenyl octyl ether containing tetrabromophenolphthalein ethyl ester. Under the optimal flow conditions of the FIA system, the CS-optode showed a good linear relationship between the peak heights in the absorbance, and the concentrations of CS in a concentration range from 50 to 400 μmol dm -3 . The sample throughput of the present system for the determination of a CS ion (300 μmol dm -3 zephiramine) was ca. 11 samples h -1 . The proposed FIA system was applied to determine the level of CS in dental rinses.
NASA Astrophysics Data System (ADS)
Yan, Hong; Song, Xiangzhong; Tian, Kuangda; Chen, Yilin; Xiong, Yanmei; Min, Shungeng
2018-02-01
A novel method, mid-infrared (MIR) spectroscopy, which enables the determination of Chlorantraniliprole in Abamectin within minutes, is proposed. We further evaluate the prediction ability of four wavelength selection methods, including bootstrapping soft shrinkage approach (BOSS), Monte Carlo uninformative variable elimination (MCUVE), genetic algorithm partial least squares (GA-PLS) and competitive adaptive reweighted sampling (CARS) respectively. The results showed that BOSS method obtained the lowest root mean squared error of cross validation (RMSECV) (0.0245) and root mean squared error of prediction (RMSEP) (0.0271), as well as the highest coefficient of determination of cross-validation (Qcv2) (0.9998) and the coefficient of determination of test set (Q2test) (0.9989), which demonstrated that the mid infrared spectroscopy can be used to detect Chlorantraniliprole in Abamectin conveniently. Meanwhile, a suitable wavelength selection method (BOSS) is essential to conducting a component spectral analysis.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wu, Chengyin, E-mail: cywu@pku.edu.cn; Liu, Yunquan; Gong, Qihuang
2014-04-14
We experimentally reconstructed the structure of the N{sub 2}Ar van der Waals complex with the technique of laser-based channel-selected Coulomb explosion imaging. The internuclear distance between the N{sub 2} center of mass and the Ar atom, i.e., the length of the van der Waals bond, was determined to be 3.88 Å from the two-body explosion channels. The angle between the van der Waals bond and the N{sub 2} principal axis was determined to be 90° from the three-body explosion channels. The reconstructed structure was contrasted with our high level ab initio calculations. The agreement demonstrated the potential application of laser-basedmore » Coulomb explosion in imaging transient molecular structure, particularly for floppy van der Waals complexes, whose structures remain difficult to be determined by conventional spectroscopic methods.« less
Radiation analysis devices, radiation analysis methods, and articles of manufacture
Roybal, Lyle Gene
2010-06-08
Radiation analysis devices include circuitry configured to determine respective radiation count data for a plurality of sections of an area of interest and combine the radiation count data of individual of sections to determine whether a selected radioactive material is present in the area of interest. An amount of the radiation count data for an individual section is insufficient to determine whether the selected radioactive material is present in the individual section. An article of manufacture includes media comprising programming configured to cause processing circuitry to perform processing comprising determining one or more correction factors based on a calibration of a radiation analysis device, measuring radiation received by the radiation analysis device using the one or more correction factors, and presenting information relating to an amount of radiation measured by the radiation analysis device having one of a plurality of specified radiation energy levels of a range of interest.
A kinetic method for the determination of thiourea by its catalytic effect in micellar media
NASA Astrophysics Data System (ADS)
Abbasi, Shahryar; Khani, Hossein; Gholivand, Mohammad Bagher; Naghipour, Ali; Farmany, Abbas; Abbasi, Freshteh
2009-03-01
A highly sensitive, selective and simple kinetic method was developed for the determination of trace levels of thiourea based on its catalytic effect on the oxidation of janus green in phosphoric acid media and presence of Triton X-100 surfactant without any separation and pre-concentration steps. The reaction was monitored spectrophotometrically by tracing the formation of the green-colored oxidized product of janus green at 617 nm within 15 min of mixing the reagents. The effect of some factors on the reaction speed was investigated. Following the recommended procedure, thiourea could be determined with linear calibration graph in 0.03-10.00 μg/ml range. The detection limit of the proposed method is 0.02 μg/ml. Most of foreign species do not interfere with the determination. The high sensitivity and selectivity of the proposed method allowed its successful application to fruit juice and industrial waste water.
Saad, Ahmed S; Attia, Ali K; Alaraki, Manal S; Elzanfaly, Eman S
2015-11-05
Five different spectrophotometric methods were applied for simultaneous determination of fenbendazole and rafoxanide in their binary mixture; namely first derivative, derivative ratio, ratio difference, dual wavelength and H-point standard addition spectrophotometric methods. Different factors affecting each of the applied spectrophotometric methods were studied and the selectivity of the applied methods was compared. The applied methods were validated as per the ICH guidelines and good accuracy; specificity and precision were proven within the concentration range of 5-50 μg/mL for both drugs. Statistical analysis using one-way ANOVA proved no significant differences among the proposed methods for the determination of the two drugs. The proposed methods successfully determined both drugs in laboratory prepared and commercially available binary mixtures, and were found applicable for the routine analysis in quality control laboratories. Copyright © 2015 Elsevier B.V. All rights reserved.
Prischi, Filippo; Pastore, Annalisa
2016-01-01
The current main challenge of Structural Biology is to undertake the structure determination of increasingly complex systems in the attempt to better understand their biological function. As systems become more challenging, however, there is an increasing demand for the parallel use of more than one independent technique to allow pushing the frontiers of structure determination and, at the same time, obtaining independent structural validation. The combination of different Structural Biology methods has been named hybrid approaches. The aim of this review is to critically discuss the most recent examples and new developments that have allowed structure determination or experimentally-based modelling of various molecular complexes selecting them among those that combine the use of nuclear magnetic resonance and small angle scattering techniques. We provide a selective but focused account of some of the most exciting recent approaches and discuss their possible further developments.
Tulchinsky, Alexander Y; Johnson, Norman A; Watt, Ward B; Porter, Adam H
2014-11-01
Postzygotic isolation between incipient species results from the accumulation of incompatibilities that arise as a consequence of genetic divergence. When phenotypes are determined by regulatory interactions, hybrid incompatibility can evolve even as a consequence of parallel adaptation in parental populations because interacting genes can produce the same phenotype through incompatible allelic combinations. We explore the evolutionary conditions that promote and constrain hybrid incompatibility in regulatory networks using a bioenergetic model (combining thermodynamics and kinetics) of transcriptional regulation, considering the bioenergetic basis of molecular interactions between transcription factors (TFs) and their binding sites. The bioenergetic parameters consider the free energy of formation of the bond between the TF and its binding site and the availability of TFs in the intracellular environment. Together these determine fractional occupancy of the TF on the promoter site, the degree of subsequent gene expression and in diploids, and the degree of dominance among allelic interactions. This results in a sigmoid genotype-phenotype map and fitness landscape, with the details of the shape determining the degree of bioenergetic evolutionary constraint on hybrid incompatibility. Using individual-based simulations, we subjected two allopatric populations to parallel directional or stabilizing selection. Misregulation of hybrid gene expression occurred under either type of selection, although it evolved faster under directional selection. Under directional selection, the extent of hybrid incompatibility increased with the slope of the genotype-phenotype map near the derived parental expression level. Under stabilizing selection, hybrid incompatibility arose from compensatory mutations and was greater when the bioenergetic properties of the interaction caused the space of nearly neutral genotypes around the stable expression level to be wide. F2's showed higher hybrid incompatibility than F1's to the extent that the bioenergetic properties favored dominant regulatory interactions. The present model is a mechanistically explicit case of the Bateson-Dobzhansky-Muller model, connecting environmental selective pressure to hybrid incompatibility through the molecular mechanism of regulatory divergence. The bioenergetic parameters that determine expression represent measurable properties of transcriptional regulation, providing a predictive framework for empirical studies of how phenotypic evolution results in epistatic incompatibility at the molecular level in hybrids. Copyright © 2014 by the Genetics Society of America.
Ionic Association Ion-Selective Electrode Experiment.
ERIC Educational Resources Information Center
Emara, Mostafa M.; And Others
1979-01-01
Describes an experiment that, using a commercially available solid-state selective electrode in conjunction with a pH-meter, determines the stability constants of sodium sulfate while varying the ionic strength of the media using sodium chloride. Detailed reproducible procedures of both the measurements and calculations are described. (BT)
Analyses of Selected Automotive Parts and Assemblies for Cost and Material Impacts
DOT National Transportation Integrated Search
1979-03-01
This is a study of selected automotive parts and assemblies analyzed to determine the elements of manufacturing cost and methods of production. Parts from the 1975 Ford Pinto, 1975 Chevelle, 1976 Audi 100LS, and the VW Rabbit are included in the sele...
40 CFR 761.240 - Scope and definitions.
Code of Federal Regulations, 2014 CFR
2014-07-01
...: Selecting Sample Sites, Collecting Surface Samples, and Analyzing Standard PCB Wipe Samples § 761.240 Scope and definitions. (a) Use these procedures to select surface sampling sites for natural gas pipe to determine its PCB surface concentration for abandonment-in-place or removal and disposal off-site in...
40 CFR 761.240 - Scope and definitions.
Code of Federal Regulations, 2011 CFR
2011-07-01
...: Selecting Sample Sites, Collecting Surface Samples, and Analyzing Standard PCB Wipe Samples § 761.240 Scope and definitions. (a) Use these procedures to select surface sampling sites for natural gas pipe to determine its PCB surface concentration for abandonment-in-place or removal and disposal off-site in...
40 CFR 761.240 - Scope and definitions.
Code of Federal Regulations, 2012 CFR
2012-07-01
...: Selecting Sample Sites, Collecting Surface Samples, and Analyzing Standard PCB Wipe Samples § 761.240 Scope and definitions. (a) Use these procedures to select surface sampling sites for natural gas pipe to determine its PCB surface concentration for abandonment-in-place or removal and disposal off-site in...
40 CFR 761.240 - Scope and definitions.
Code of Federal Regulations, 2013 CFR
2013-07-01
...: Selecting Sample Sites, Collecting Surface Samples, and Analyzing Standard PCB Wipe Samples § 761.240 Scope and definitions. (a) Use these procedures to select surface sampling sites for natural gas pipe to determine its PCB surface concentration for abandonment-in-place or removal and disposal off-site in...
Selection of Stream Insect Larvae for Indicating Anthropogenic Impact
This study examined the total mercury concentrations, [Hg], and 15N values in macro-invertebrates collected from 35 stream sites in Rhode Island, USA, to determine the organism groups most suitable for use as indicators of anthropogenic impact. Site selection was designed to cov...
Impact of Selection for Uterine Capacity on the Placental Transcriptome
USDA-ARS?s Scientific Manuscript database
Direct single trait selection for 11 generations resulted in a 1.6 pig advantage for uterine capacity (UC) while average birth and placental weights at term remained unchanged. A serial slaughter experiment conducted throughout gestation determined the critical time period for the line difference ...
Digital design using selection operations
NASA Technical Reports Server (NTRS)
Miles, Lowell H. (Inventor); Whitaker, Sterling R. (Inventor); Cameron, Eric G. (Inventor)
2004-01-01
A digital integrated circuit chip is designed by identifying a logical structure to be implemented. This logical structure is represented in terms of a logical operations, at least 5% of which include selection operations. A determination is made of logic cells that correspond to an implementation of these logical operations.
29 CFR 1607.1 - Statement of purpose.
Code of Federal Regulations, 2014 CFR
2014-07-01
... incorporate a single set of principles which are designed to assist employers, labor organizations, employment... are designed to provide a framework for determining the proper use of tests and other selection procedures. These guidelines do not require a user to conduct validity studies of selection procedures where...
29 CFR 1607.1 - Statement of purpose.
Code of Federal Regulations, 2011 CFR
2011-07-01
... incorporate a single set of principles which are designed to assist employers, labor organizations, employment... are designed to provide a framework for determining the proper use of tests and other selection procedures. These guidelines do not require a user to conduct validity studies of selection procedures where...
29 CFR 1607.1 - Statement of purpose.
Code of Federal Regulations, 2012 CFR
2012-07-01
... incorporate a single set of principles which are designed to assist employers, labor organizations, employment... are designed to provide a framework for determining the proper use of tests and other selection procedures. These guidelines do not require a user to conduct validity studies of selection procedures where...
29 CFR 1607.1 - Statement of purpose.
Code of Federal Regulations, 2013 CFR
2013-07-01
... incorporate a single set of principles which are designed to assist employers, labor organizations, employment... are designed to provide a framework for determining the proper use of tests and other selection procedures. These guidelines do not require a user to conduct validity studies of selection procedures where...
29 CFR 1607.1 - Statement of purpose.
Code of Federal Regulations, 2010 CFR
2010-07-01
... incorporate a single set of principles which are designed to assist employers, labor organizations, employment... are designed to provide a framework for determining the proper use of tests and other selection procedures. These guidelines do not require a user to conduct validity studies of selection procedures where...
43 CFR 32.4 - Program operation requirements.
Code of Federal Regulations, 2010 CFR
2010-10-01
... for the management of each Corps camp and project, final selection of enrollees, determination of... refer all candidates who self-certify that they meet eligibility requirements to Grantees for selection of those to be enrolled. Self-certification by applicants ages 16 through 18 who have left school...
Advanced fiber information systems seed coat neps baseline response from diverse mediums
USDA-ARS?s Scientific Manuscript database
An extensive literature search has revealed that no papers have been published regarding selectivity calculation of the AFIS seed coat neps (SCN) determination over interfering material in cotton. A prerequisite to selectivity measurements is to identify suitable fiber medium(s) that give baseline ...
Coloured Immigrants in Britain: A Selected Bibliography.
ERIC Educational Resources Information Center
Sivanandan, A., Comp.
This edition of this select bibliography has been compiled on the basis of interest, point of view, and usefulness to the reader. The subject division of the contents (determined according to reader usefulness) includes bibliographies listing: education and family; adjustment and integration; area studies; associations, organizations, and pressure…
48 CFR 536.602-1 - Selection criteria.
Code of Federal Regulations, 2014 CFR
2014-10-01
... Selection criteria. (a) FAR 36.602-1 requires that agencies include “location in the general geographical... services (based on the total contract price) will be accomplished within the geographical boundaries... not apply to projects that the Chief Architect of GSA determines have national significance. (b) The...
48 CFR 536.602-1 - Selection criteria.
Code of Federal Regulations, 2012 CFR
2012-10-01
... Selection criteria. (a) FAR 36.602-1 requires that agencies include “location in the general geographical... services (based on the total contract price) will be accomplished within the geographical boundaries... not apply to projects that the Chief Architect of GSA determines have national significance. (b) The...
48 CFR 536.602-1 - Selection criteria.
Code of Federal Regulations, 2013 CFR
2013-10-01
... Selection criteria. (a) FAR 36.602-1 requires that agencies include “location in the general geographical... services (based on the total contract price) will be accomplished within the geographical boundaries... not apply to projects that the Chief Architect of GSA determines have national significance. (b) The...
48 CFR 536.602-1 - Selection criteria.
Code of Federal Regulations, 2011 CFR
2011-10-01
... Selection criteria. (a) FAR 36.602-1 requires that agencies include “location in the general geographical... services (based on the total contract price) will be accomplished within the geographical boundaries... not apply to projects that the Chief Architect of GSA determines have national significance. (b) The...
42 CFR 73.9 - Responsible Official.
Code of Federal Regulations, 2013 CFR
2013-10-01
... SELECT AGENTS AND TOXINS § 73.9 Responsible Official. (a) An individual or entity required to register... onsite incidents involving select agents and toxins in accordance with the entity's incident response... toxins are stored or used in order to determine compliance with the requirements of this part. The...
42 CFR 73.9 - Responsible Official.
Code of Federal Regulations, 2014 CFR
2014-10-01
... SELECT AGENTS AND TOXINS § 73.9 Responsible Official. (a) An individual or entity required to register... onsite incidents involving select agents and toxins in accordance with the entity's incident response... toxins are stored or used in order to determine compliance with the requirements of this part. The...
Media for aerobic recovery of campylobacter from mixed bacterial cultures
USDA-ARS?s Scientific Manuscript database
A non-selective medium for culturing Campylobacter aerobically was recently described. The objective of the present study was to determine if a selective medium could be formulated by supplementing the new medium with the Bolton antibiotic mixture. Basal medium containing beef extract, 50 g; tryptos...
Antibiotic profiles of bacteria isolated on selective campylobacter media
USDA-ARS?s Scientific Manuscript database
The objective of this study was to determine antibiotic profiles of non-Campylobacter bacteria recovered on selective Campylobacter media. Broiler carcasses were obtained from a processing facility, and whole-carcass rinses were performed by shaking carcasses in plastic bags with 200 mL of distilled...
Pollution Police: How to Determine Spectroscopic Selection Rules
ERIC Educational Resources Information Center
Selco, Jodye I.; Beery, Janet
2004-01-01
Students employ mathematics and physical chemistry in a project called Pollution Police to establish spectroscopic selection rules, and apply them to detect environmental contaminants from infrared spectra. This interdisciplinary project enables students to gain multiple information on molecular symmetry, and its role in the development of…
Federal Register 2010, 2011, 2012, 2013, 2014
2011-09-09
... on-base parking demand (negative factor) or relieves parking demand (positive factor); (ii) the... four different comments. The public comments were considered by OEA in determining the final selection... of mitigation (positive factor) or contribution to vulnerability to a terrorist attack or major...
Introductory Courses and the Search
ERIC Educational Resources Information Center
Schaffer, Dennis R.; Purohit, Anal
1975-01-01
This study surveyed 363 undergraduate students to determine the extent that introductory courses affected their selection of majors, minors, and career goals. The results indicated a significant relationship between an instructor perceived by students as better than average in teaching an introductory course and the selection of a major. (Author)
Dakova, Ivanka; Karadjova, Irina; Georgieva, Ventsislava; Georgiev, George
2009-04-30
Metal ion-imprinted polymer particles have been prepared by copolymerization of methacrylic acid as monomer, trimethylolpropane trimethacrylate as cross-linking agent and 2,2'-azobisisobutyronitrile as initiator, in the presence of Hg(II)-1-(2-thiazolylazo)-2-naphthol complex. The separation and preconcentration characteristics of the Hg-ion-imprinted microbeads for inorganic mercury have been investigated by batch procedure. The optimal pH value for the quantitative sorption is 7. The adsorbed inorganic mercury is easily eluted by 2 mL 4M HNO(3). The adsorption capacity of the newly synthesized Hg ion-imprinted microbeads is 32.0 micromol g(-1) for dry copolymer. The selectivity of the copolymer toward inorganic mercury (Hg(II)) ion is confirmed through the comparison of the competitive adsorptions of Cd(II), Co(II), Cu(II), Ni(II), Pb(II), Zn(II)) and high values of the selectivity and distribution coefficients have been calculated. Experiments performed for selective determination of inorganic mercury in mineral and sea waters showed that the interfering matrix does not influence the extraction efficiency of Hg ion-imprinted microbeads. The detection limit for inorganic mercury is 0.006 microg L(-1) (3 sigma), determined by cold vapor atomic adsorption spectrometry. The relative standard deviation varied in the range 5-9 % at 0.02-1 microg L(-1) Hg levels. The new Hg-ion-imprinted microbeads have been tested and applied for the speciation of Hg in river and mineral waters: inorganic mercury has been determined selectively in nondigested sample, while total mercury e.g. sum of inorganic and methylmercury, has been determined in digested sample.
Two spectrophotometric methods for simultaneous determination of some antihyperlipidemic drugs
Abdelwahab, Nada S.; El-Zeiny, Badr A.; Tohamy, Salwa I.
2012-01-01
Two simple, accurate, precise and economic spectrophotometric methods have been developed for simultaneous determination of Atorvastatin calcium (ATR) and Ezetimibe (EZ) in their bulk powder and pharmaceutical dosage form. Method (I) is based on dual wavelength analysis while method (II) is the mean centering of ratio spectra spectrophotometric (MCR) method. In method (I), two wavelengths were selected for each drug in such a way that the difference in absorbance was zero for the second drug. At wavelengths 226.6 and 244 nm EZ had equal absorbance values; therefore, these two wavelengths have been used to determine ATR; on a similar basis 228.6 and 262.8 nm were selected to determine EZ in their binary mixtures. In method II, the absorption spectra of both ATR and EZ with different concentrations were recorded over the range 200–350, divided by the spectrum of suitable divisor of both ATR and EZ and then the obtained ratio spectra were mean centered. The concentrations of active components were then determined from the calibration graphs obtained by measuring the amplitudes at 215–260 nm (peak to peak) for both ATR and EZ. Accuracy and precision of the developed methods have been tested; in addition recovery studies have been carried out in order to confirm their accuracy. On the other hand, selectivities of the methods were tested by application for determination of different synthetic mixtures containing different ratios of the studied drugs. The developed methods have been successfully used for determination of ATR and EZ in their combined dosage form and statistical comparison of the developed methods with the reported spectrophotometric one using F and Student's t-tests showed no significant difference regarding both accuracy and precision. PMID:29403754
Two spectrophotometric methods for simultaneous determination of some antihyperlipidemic drugs.
Abdelwahab, Nada S; El-Zeiny, Badr A; Tohamy, Salwa I
2012-08-01
Two simple, accurate, precise and economic spectrophotometric methods have been developed for simultaneous determination of Atorvastatin calcium (ATR) and Ezetimibe (EZ) in their bulk powder and pharmaceutical dosage form. Method (I) is based on dual wavelength analysis while method (II) is the mean centering of ratio spectra spectrophotometric (MCR) method. In method (I), two wavelengths were selected for each drug in such a way that the difference in absorbance was zero for the second drug. At wavelengths 226.6 and 244 nm EZ had equal absorbance values; therefore, these two wavelengths have been used to determine ATR; on a similar basis 228.6 and 262.8 nm were selected to determine EZ in their binary mixtures. In method II, the absorption spectra of both ATR and EZ with different concentrations were recorded over the range 200-350, divided by the spectrum of suitable divisor of both ATR and EZ and then the obtained ratio spectra were mean centered. The concentrations of active components were then determined from the calibration graphs obtained by measuring the amplitudes at 215-260 nm (peak to peak) for both ATR and EZ. Accuracy and precision of the developed methods have been tested; in addition recovery studies have been carried out in order to confirm their accuracy. On the other hand, selectivities of the methods were tested by application for determination of different synthetic mixtures containing different ratios of the studied drugs. The developed methods have been successfully used for determination of ATR and EZ in their combined dosage form and statistical comparison of the developed methods with the reported spectrophotometric one using F and Student's t -tests showed no significant difference regarding both accuracy and precision.
Baconguis, Isabelle; Bohlen, Christopher J; Goehring, April; Julius, David; Gouaux, Eric
2014-02-13
Acid-sensing ion channels (ASICs) detect extracellular protons produced during inflammation or ischemic injury and belong to the superfamily of degenerin/epithelial sodium channels. Here, we determine the cocrystal structure of chicken ASIC1a with MitTx, a pain-inducing toxin from the Texas coral snake, to define the structure of the open state of ASIC1a. In the MitTx-bound open state and in the previously determined low-pH desensitized state, TM2 is a discontinuous α helix in which the Gly-Ala-Ser selectivity filter adopts an extended, belt-like conformation, swapping the cytoplasmic one-third of TM2 with an adjacent subunit. Gly 443 residues of the selectivity filter provide a ring of three carbonyl oxygen atoms with a radius of ∼3.6 Å, presenting an energetic barrier for hydrated ions. The ASIC1a-MitTx complex illuminates the mechanism of MitTx action, defines the structure of the selectivity filter of voltage-independent, sodium-selective ion channels, and captures the open state of an ASIC. Copyright © 2014 Elsevier Inc. All rights reserved.
NASA Astrophysics Data System (ADS)
Chen, Hui; Tan, Chao; Lin, Zan; Wu, Tong
2018-01-01
Milk is among the most popular nutrient source worldwide, which is of great interest due to its beneficial medicinal properties. The feasibility of the classification of milk powder samples with respect to their brands and the determination of protein concentration is investigated by NIR spectroscopy along with chemometrics. Two datasets were prepared for experiment. One contains 179 samples of four brands for classification and the other contains 30 samples for quantitative analysis. Principal component analysis (PCA) was used for exploratory analysis. Based on an effective model-independent variable selection method, i.e., minimal-redundancy maximal-relevance (MRMR), only 18 variables were selected to construct a partial least-square discriminant analysis (PLS-DA) model. On the test set, the PLS-DA model based on the selected variable set was compared with the full-spectrum PLS-DA model, both of which achieved 100% accuracy. In quantitative analysis, the partial least-square regression (PLSR) model constructed by the selected subset of 260 variables outperforms significantly the full-spectrum model. It seems that the combination of NIR spectroscopy, MRMR and PLS-DA or PLSR is a powerful tool for classifying different brands of milk and determining the protein content.
Pulgar, José; Waldisperg, Melany; Galbán-Malagón, Cristóbal; Maturana, Diego; Pulgar, Victor M; Aldana, Marcela
2017-02-01
The amount of ultraviolet (UV) radiation reaching the earth's surface has increased due to ozone layer depletion, and this fact represents an opportunity to evaluate the physiological and behavioral responses of animals to this global-scale stressor. The transitory fish Girella laevifrons inhabits pools in the upper intertidal zone, which is characterized by exposure to a wide range of stressors, including UV radiation. We documented the field magnitude and the impact of UV radiation on oxygen consumption, body mass variations, and shelter (rocky and algae) selection by G. laevifrons. UV-exposed animals showed increased oxygen consumption, slower body weight increase, and active rocky shelter selection. Control fish showed increased body weight and no evident shelter selection. The results indicated that UV exposure affects fish energetic balance and habitat selection to favor greater protection against radiation. Increased UV exposure in transitory intertidal animals at levels observed in upper intertidal pools may alter the residency time of fish before leaving for the subtidal zone. Therefore, UV-induced energetic changes may determine animal performance and ontogenetic physiological itineraries, whereas shelter quality might determine habitat use. Copyright © 2016 Elsevier B.V. All rights reserved.
Pace, M.N.; Rosentreter, J.J.; Bartholomay, R.C.
2001-01-01
Idaho State University and the US Geological Survey, in cooperation with the US Department of Energy, conducted a study to determine and evaluate strontium distribution coefficients (Kds) of subsurface materials at the Idaho National Engineering and Environmental Laboratory (INEEL). The Kds were determined to aid in assessing the variability of strontium Kds and their effects on chemical transport of strontium-90 in the Snake River Plain aquifer system. Data from batch experiments done to determine strontium Kds of five sediment-infill samples and six standard reference material samples were analyzed by using multiple linear regression analysis and the stepwise variable-selection method in the statistical program, Statistical Product and Service Solutions, to derive an equation of variables that can be used to predict strontium Kds of sediment-infill samples. The sediment-infill samples were from basalt vesicles and fractures from a selected core at the INEEL; strontium Kds ranged from ???201 to 356 ml g-1. The standard material samples consisted of clay minerals and calcite. The statistical analyses of the batch-experiment results showed that the amount of strontium in the initial solution, the amount of manganese oxide in the sample material, and the amount of potassium in the initial solution are the most important variables in predicting strontium Kds of sediment-infill samples.
NASA Astrophysics Data System (ADS)
Chen, Suming; Zhang, Zhujun
2008-06-01
The method of synthesis and evaluation of molecularly imprinted polymers was reported. As a selective solid-phase extraction sorbent, the polymers were coupled with electrochemical fluorimetry detection for the efficient determination of methotrexate in serum and urine. Methotrexate was preconcentrated in the molecularly imprinted solid-phase extraction microcolumn packed with molecularly imprinted polymers, and then eluted. The eluate was detected by fluorescence spectrophotometer after electrochemical oxidation. The conditions of preconcentration, elution, electrochemical oxidation and determination were carefully studied. Under the selected experimental conditions, the calibration graph of the fluorescence intensity versus methotrexate concentration was linear from 4 × 10 -9 g mL -1 to 5 × 10 -7 g mL -1, and the detection limit was 8.2 × 10 -10 g mL -1 (3 σ). The relative standard deviation was 3.92% ( n = 7) for 1 × 10 -7 g mL -1 methotrexate. The experiments showed that the selectivity and sensitivity of fluorimetry could be greatly improved by the proposed method. This method has been successfully applied to the determination of methotrexate. At the same time, the binding characteristics of the polymers to the methotrexate were evaluated by batch and dynamic methods.
NASA Astrophysics Data System (ADS)
Cheluszka, Piotr
2017-12-01
This article discusses the issue of selecting a pick system for cutting mining machinery, concerning the reduction of vibrations in the cutting system, particularly in a load-carrying structure at work. Numerical analysis was performed on a telescopic roadheader boom equipped with transverse heads. A frequency range of the boom's free vibrations with a set structure and dynamic properties were determined based on a dynamic model. The main components excited by boom vibrations, generated through the process of cutting rock, were identified. This was closely associated with the stereometry of the cutting heads. The impact on the pick system (the number of picks and their arrangement along the side of the cutting head) was determined by the intensity of the external boom load elements, especially in resonance zones. In terms of the anti-resonance criterion, an advantageous system of cutting head picks was determined as a result of the analysis undertaken. The correct selection of the pick system was ascertained based on a computer simulation of the dynamic loads and vibrations of a roadheader telescopic boom.
NASA Astrophysics Data System (ADS)
Zargoosh, Kiomars; Babadi, Fatemeh Farhadian
2015-02-01
A highly sensitive and selective optical membrane for determination of Hg2+ and Pb2+ was prepared by covalent immobilization of dithizone on agarose membrane. In addition to its high stability, reproducibility and relatively long lifetime, the proposed optical sensor revealed good selectivity for target ions over a large number of alkali, alkaline earth, transition, and heavy metal ions. The proposed optical membrane displays linear responses from 1.1 × 10-8 to 2.0 × 10-6 mol L-1 and 1.2 × 10-8 to 2.4 × 10-6 mol L-1 for Hg2+ and Pb2+, respectively. The limits of detection (LOD) were 2.0 × 10-9 mol L-1 and 4.0 × 10-9 mol L-1 for Hg2+ and Pb2, respectively. The prepared optical membrane was successfully applied to the determination of Hg2+ and Pb2+ in industrial wastes, spiked tap water and natural waters without any preconcentration step.
Aptamer Recognition of Multiplexed Small-Molecule-Functionalized Substrates.
Nakatsuka, Nako; Cao, Huan H; Deshayes, Stephanie; Melkonian, Arin Lucy; Kasko, Andrea M; Weiss, Paul S; Andrews, Anne M
2018-05-31
Aptamers are chemically synthesized oligonucleotides or peptides with molecular recognition capabilities. We investigated recognition of substrate-tethered small-molecule targets, using neurotransmitters as examples, and fluorescently labeled DNA aptamers. Substrate regions patterned via microfluidic channels with dopamine or L-tryptophan were selectively recognized by previously identified dopamine or L-tryptophan aptamers, respectively. The on-substrate dissociation constant determined for the dopamine aptamer was comparable to, though slightly greater than the previously determined solution dissociation constant. Using pre-functionalized neurotransmitter-conjugated oligo(ethylene glycol) alkanethiols and microfluidics patterning, we produced multiplexed substrates to capture and to sort aptamers. Substrates patterned with L-DOPA, L-DOPS, and L-5-HTP enabled comparison of the selectivity of the dopamine aptamer for different targets via simultaneous determination of in situ binding constants. Thus, beyond our previous demonstrations of recognition by protein binding partners (i.e., antibodies and G-protein-coupled receptors), strategically optimized small-molecule-functionalized substrates show selective recognition of nucleic acid binding partners. These substrates are useful for side-by-side target comparisons, and future identification and characterization of novel aptamers targeting neurotransmitters or other important small-molecules.
Carpenter, C E
1992-01-01
The cost of capital for hospitals is a topic of continuing interest as Medicare's new capital payment policy is implemented. This study examines the determinants of tax-exempt revenue bond yields, the primary source of long-term capital for hospitals. Two important methodological issues are addressed. A probit analysis estimates the probability that a hospital or system will be observed in the tax-exempt market. A selection-corrected two-stage least squares analysis allows for the simultaneous determination of bond yield and bond size. The study is based on a sample of hospitals that issued tax-exempt revenue bonds in 1982-1984, the years immediately surrounding implementation of Medicare's new payment system based on diagnosis-related groups, and an equal number of hospitals not in the market during the study period. Results suggest that hospital systems and hospitals with high occupancy rates are most likely to enter the tax-exempt revenue bond market. The yield equation suggests that hospital-specific variables may not be good predictors of the cost of capital once estimates are corrected for selection. PMID:1464540
Carpenter, C E
1992-12-01
The cost of capital for hospitals is a topic of continuing interest as Medicare's new capital payment policy is implemented. This study examines the determinants of tax-exempt revenue bond yields, the primary source of long-term capital for hospitals. Two important methodological issues are addressed. A probit analysis estimates the probability that a hospital or system will be observed in the tax-exempt market. A selection-corrected two-stage least squares analysis allows for the simultaneous determination of bond yield and bond size. The study is based on a sample of hospitals that issued tax-exempt revenue bonds in 1982-1984, the years immediately surrounding implementation of Medicare's new payment system based on diagnosis-related groups, and an equal number of hospitals not in the market during the study period. Results suggest that hospital systems and hospitals with high occupancy rates are most likely to enter the tax-exempt revenue bond market. The yield equation suggests that hospital-specific variables may not be good predictors of the cost of capital once estimates are corrected for selection.
A Study of Regional Waveform Calibration in the Eastern Mediterranean Region.
NASA Astrophysics Data System (ADS)
di Luccio, F.; Pino, A.; Thio, H.
2002-12-01
We modeled Pnl phases from several moderate magnitude events in the eastern Mediterranean to test methods and to develop path calibrations for source determination. The study region spanning from the eastern part of the Hellenic arc to the eastern Anatolian fault is mostly interested by moderate earthquakes, that can produce relevant damages. The selected area consists of several tectonic environment, which produces increased level of difficulty in waveform modeling. The results of this study are useful for the analysis of regional seismicity and for seismic hazard as well, in particular because very few broadband seismic stations are available in the selected area. The obtained velocity model gives a 30 km crustal tickness and low upper mantle velocities. The applied inversion procedure to determine the source mechanism has been successful, also in terms of discrimination of depth, for the entire range of selected paths. We conclude that using the true calibration of the seismic structure and high quality broadband data, it is possible to determine the seismic source in terms of mechanism, even with a single station.
Kurihara, Takamasa; Min, Jun Zhe; Hirata, Asuka; Toyo'oka, Toshimasa; Inagaki, Shinsuke
2009-05-01
Rapid, selective and sensitive determination of N-linked oligosaccharides in glycoproteins (ovalbumin, ribonuclease B and fetuin) was performed by ultra-performance liquid chromatography (UPLC) with fluorescence (FL) and electrospray ionization time-of-flight mass spectrometry (ESI-TOF-MS). The asparaginyl-oligosaccharide moiety was first liberated from each glycoprotein by pronase E (a proteolitic enzyme). The oligosaccharide fractions separated by gel-permeation chromatography were labeled with 1-pyrenesulfonyl chloride (PSC, a fluorescence reagent), separated by UPLC in a short run time, and then detected by FL and TOF-MS. The PSC-labeled oligosaccharides were selectively identified from the FL detection and then sensitively determined by ESI-TOF-MS. As the results, 15, eight and four kinds of N-linked oligosaccharides were detected from ovalbumin, ribonuclease B and fetuin, respectively. Because the present method is rapid (within 9 min), selective and sensitive (approximate 60 fmol, S/N = 5), the determination of N-linked oligosaccharides in various glycoproteins seems to be possible.
Taxus ingredients in the red arils of Taxus baccata L. determined by HPLC-MS/MS.
Siegle, Lydia; Pietsch, Jörg
2018-02-09
Taxus baccata L. is an evergreen conifer whose plant parts are cardiotoxic. Only the red arils of the berries are described as non-toxic and taxane-free. Extraction and HPLC-MS/MS methods were developed for the investigation of the Taxus compounds 3,5-dimethoxyphenol, 10-deacetylbaccatin III, baccatin III, cephalomannine, taxol A and taxinine M in the red arils of the yew berries. MethodologyA liquid-liquid extraction method for the red arils of the fruits from three yews were developed. An accurate (ESI+) HPLC-MS/MS method was performed for the simultaneous detection and determination of the target compounds in multiple reaction monitoring (MRM) mode. All Taxus agents obtained were detected in the red arils. Highest concentrations were determined for baccatin III and 10-deacetylbaccatin III. The developed quantitative method is reliable and selective and was successfully applied for quantification of selected Taxus ingredients in red arils of Taxus baccata. It was disproved that the red arils of the berries do not contain the selected Taxus compounds. Copyright © 2018 John Wiley & Sons, Ltd.
Fisher, Simon D.; Reynolds, John N. J.
2014-01-01
Anatomical investigations have revealed connections between the intralaminar thalamic nuclei and areas such as the superior colliculus (SC) that receive short latency input from visual and auditory primary sensory areas. The intralaminar nuclei in turn project to the major input nucleus of the basal ganglia, the striatum, providing this nucleus with a source of subcortical excitatory input. Together with a converging input from the cerebral cortex, and a neuromodulatory dopaminergic input from the midbrain, the components previously found necessary for reinforcement learning in the basal ganglia are present. With this intralaminar sensory input, the basal ganglia are thought to play a primary role in determining what aspect of an organism’s own behavior has caused salient environmental changes. Additionally, subcortical loops through thalamic and basal ganglia nuclei are proposed to play a critical role in action selection. In this mini review we will consider the anatomical and physiological evidence underlying the existence of these circuits. We will propose how the circuits interact to modulate basal ganglia output and solve common behavioral learning problems of agency determination and action selection. PMID:24765070
Distribution of thiobarbituric acid-reactive substances in lipoproteins and proteins in serum.
Bonnefont, D; Legrand, A; Peynet, J; Emerit, J; Delattre, J; Galli, A
1989-10-01
We assessed the distribution of malondialdehyde (MDA) in lipoproteins and proteins in serum after using two procedures to separate the lipoproteins: sequential ultracentrifugation or selective precipitation with a sodium phosphotungstate and magnesium chloride reagent followed by ultracentrifugation of the supernate. MDA concentrations were determined by the thiobarbituric acid reaction and quantified by fluorometry. We found that 43% of the thiobarbituric acid-reactive substances (TBARS) was bound to the lipoproteins--27% to very-low- and low-density lipoproteins (VLDL-LDL) and 16% to high-density lipoproteins (HDL)--and from 11.5% to 15.8% to proteins, depending on the separation procedure. Residual unbound TBARS were located in the ultracentrifugation layers that contained no lipoproteins or proteins. The TBARS concentration in serum lipoproteins containing apolipoprotein B (i.e., VLDL-LDL) was the same after ultracentrifugation or selective precipitation. We therefore consider the precipitation method more suitable for routine TBARS determination in these lipoproteins, because it is easier to handle and faster. However, for determination of TBARS in HDL, selective precipitation requires subsequent ultracentrifugation at a density of 1.21 kg/L.
Yang, Xun; Wang, Ruiling; Wang, Weihua; Yan, Hongyuan; Qiu, Mande; Song, Yanxue
2014-01-15
A novel molecularly imprinted organic-inorganic hybrid polymer (MI-MAA/APTS) based on a dummy molecular imprinting technique and an organic-inorganic hybrid material technique was synthesised and used as a sorbent in solid-phase extraction for the selective isolation and determination of ofloxacin (OFL), lomefloxacin (LOM), and ciprofloxacin (CIP) in tilapia samples. The MI-MAA/APTS sorbent was prepared from 3-aminopropyltriethoxysilanes (APTS) as an inorganic source and methacrylic acid (MAA) as an organic source and exhibited high mechanical strength and special affinities to the analytes. A comparison of MI-MAA/APTS with other conventional sorbents (C18 and HLB) showed that MI-MAA/APTS displayed good selectivity and affinity for OFL, LOM, and CIP, and the recoveries of the analytes at three spiked levels were in the range of 85.1-101.0%, with the relative standard deviations ≤5.1%. The presented MI-MAA/APTS-SPE-HPLC method could be potentially applied to the determination of fluoroquinolones (FQs) in complex fish samples. Copyright © 2013 Elsevier B.V. All rights reserved.
Application of geographical information system in disposal site selection for hazardous wastes.
Rezaeimahmoudi, Mehdi; Esmaeli, Abdolreza; Gharegozlu, Alireza; Shabanian, Hassan; Rokni, Ladan
2014-01-01
The aim of this study was to provide a scientific method based on Geographical Information System (GIS) regarding all sustainable development measures to locate a proper landfill for disposal of hazardous wastes, especially industrial (radioactive) wastes. Seven effective factors for determining hazardous waste landfill were applied in Qom Province, central Iran. These criteria included water, slope, population centers, roads, fault, protected areas and geology. The Analysis Hierarchical Process (AHP) model based on pair comparison was used. First, the weight of each factor was determined by experts; afterwards each layer of maps entered to ARC GIS and with special weight multiplied together, finally the best suitable site was introduced. The most suitable sites for burial were in northwest and west of Qom Province and eventually five zones were introduced as the sample sites. GIs and AHP model is introduced as the technical, useful and accelerator tool for disposal site selection. Furthermore it is determined that geological factor is the most effective layer for site selection. It is suggested that geological conditions should be considered primarily then other factors are taken into consideration.
Paleogene stratigraphy of the Solomons Island, Maryland corehole
Gibson, Thomas G.; Bybell, Laurel M.
1994-01-01
Purge and trap capillary gas chromatography/mass spectrometry is a rapid, precise, accurate method for determining volatile organic compounds in samples of surface water and ground water. The method can be used to determine 59 selected compounds, including chlorofluorohydrocarbons, aromatic hydrocarbons, and halogenated hydrocarbons. The volatile organic compounds are removed from the sample matrix by actively purging the sample with helium. The volatile organic compounds are collected onto a sorbant trap, thermally desorbed, separated by a Megabore gas chromatographic capillary column, ionized by electron impact, and determined by a full-scan quadrupole mass spectrometer. Compound identification is confirmed by the gas chromatographic retention time and by the resultant mass spectrum. Unknown compounds detected in a sample can be tentatively identified by comparing the unknown mass spectrum to reference spectra in the mass-spectra computer-data system library compiled by the National Institute of Standards and Technology. Method detection limits for the selected compounds range from 0.05 to 0.2 microgram per liter. Recoveries for the majority of the selected compounds ranged from 80 to 120 percent, with relative standard deviations of less than 10 percent.
Reina, P; Cointry, G R; Nocciolino, L; Feldman, S; Ferretti, J L; Rittweger, J; Capozza, R F
2015-03-01
To compare the independent influence of mechanical and non-mechanical factors on bone features, multiple regression analyses were performed between pQCT indicators of radius and tibia bone mass, mineralization, design and strength as determined variables, and age or time since menopause (TMP), body mass, bone length and regional muscles' areas as selected determinant factors, in Caucasian, physically active, untrained healthy men and pre- and post-menopausal women. In men and pre-menopausal women, the strongest influences were exerted by muscle area on radial features and by both muscle area and bone length on the tibia. Only for women, was body mass a significant factor for tibia traits. In men and pre-menopausal women, mass/design/strength indicators depended more strongly on the selected determinants than the cortical vBMD did (p<0.01-0.001 vs n.s.), regardless of age. However, TMP was an additional factor for both bones (p<0.01-0.001). The selected mechanical factors (muscle size, bone lengths) were more relevant than age/TMP or body weight to the development of allometrically-related bone properties (mass/design/strength), yet not to bone tissue 'quality' (cortical vBMD), suggesting a determinant, rather than determined role for cortical stiffness. While the mechanical impacts of muscles and bone levers on bone structure were comparable in men and pre-menopausal women, TMP exerted a stronger impact than allometric or mechanical factors on bone properties, including cortical vBMD.
Shea, Colleen; Alexoff, David L; Kim, Dohyun; Hoque, Ruma; Schueller, Michael J; Fowler, Joanna S; Qu, Wenchao
2015-08-01
In this research, we aim to directly measure the specific activity (SA) of the carbon-11 cyanide ([(11)C]CN¯) produced by our in-house built automated [(11)C]HCN production system and to identify the major sources of (12)C-cyanide ((12)CN¯). The [(11)C]CN¯ is produced from [(11)C]CO2, which is generated by the (14)N(p,α)(11)C nuclear reaction using a cyclotron. Direct measurement of cyanide concentrations was accomplished using a relatively inexpensive, and easy to use ion selective electrode (ISE) which offered an appropriate range of sensitivity for detecting mass. Multiple components of the [(11)C]HCN production system were isolated in order to determine their relative contributions to (12)CN¯ mass. It was determined that the system gases were responsible for approximately 30% of the mass, and that the molecular sieve/nickel furnace unit contributed approximately 70% of the mass. Beam on target (33µA for 1 and 10min) did not contribute significantly to the mass. Additionally, we compared the SA of our [(11)C]HCN precursor determined using the ISE to the SA of our current [(11)C]CN¯ derived radiotracers determined by HPLC to assure there was no significant difference between the two methods. These results are the first reported use of an ion selective electrode to determine the SA of no-carrier-added cyanide ion, and clearly show that it is a valuable, inexpensive and readily available tool suitable for this purpose. Copyright © 2015 Elsevier Ltd. All rights reserved.
Shea, Colleen; Alexoff, David L.; Kim, Dohyun; ...
2015-04-25
In this study, we aim to directly measure the specific activity (SA) of the carbon-11 cyanide ([ 11C]CN¯) produced by our in-house built automated [ 11C]HCN production system and to identify the major sources of 12C-cyanide ( 12CN¯). The [ 11C]CN¯ is produced from [ 11C]CO 2, which is generated by the 14N(p,α) 11C nuclear reaction using a cyclotron. Direct measurement of cyanide concentrations was accomplished using a relatively inexpensive, and easy to use ion selective electrode (ISE) which offered an appropriate range of sensitivity for detecting mass. Multiple components of the [ 11C]HCN production system were isolated in ordermore » to determine their relative contributions to 12CN¯ mass. It was determined that the system gases were responsible for approximately 30% of the mass, and that the molecular sieve/nickel furnace unit contributed approximately 70% of the mass. Beam on target (33 µA for 1 and 10 min) did not contribute significantly to the mass. Additionally, we compared the SA of our [ 11C]HCN precursor determined using the ISE to the SA of our current [ 11C]CN¯ derived radiotracers determined by HPLC to assure there was no significant difference between the two methods. These results are the first reported use of an ion selective electrode to determine the SA of no-carrier-added cyanide ion, and clearly show that it is a valuable, inexpensive and readily available tool suitable for this purpose.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Shea, Colleen; Alexoff, David L.; Kim, Dohyun
In this study, we aim to directly measure the specific activity (SA) of the carbon-11 cyanide ([ 11C]CN¯) produced by our in-house built automated [ 11C]HCN production system and to identify the major sources of 12C-cyanide ( 12CN¯). The [ 11C]CN¯ is produced from [ 11C]CO 2, which is generated by the 14N(p,α) 11C nuclear reaction using a cyclotron. Direct measurement of cyanide concentrations was accomplished using a relatively inexpensive, and easy to use ion selective electrode (ISE) which offered an appropriate range of sensitivity for detecting mass. Multiple components of the [ 11C]HCN production system were isolated in ordermore » to determine their relative contributions to 12CN¯ mass. It was determined that the system gases were responsible for approximately 30% of the mass, and that the molecular sieve/nickel furnace unit contributed approximately 70% of the mass. Beam on target (33 µA for 1 and 10 min) did not contribute significantly to the mass. Additionally, we compared the SA of our [ 11C]HCN precursor determined using the ISE to the SA of our current [ 11C]CN¯ derived radiotracers determined by HPLC to assure there was no significant difference between the two methods. These results are the first reported use of an ion selective electrode to determine the SA of no-carrier-added cyanide ion, and clearly show that it is a valuable, inexpensive and readily available tool suitable for this purpose.« less
Rios, Rodrigo S.; Vargas-Rodriguez, Renzo; Novoa-Jerez, Jose-Enrique; Squeo, Francisco A.
2017-01-01
In birds, the environmental variables and intrinsic characteristics of the nest have important fitness consequences through its influence on the selection of nesting sites. However, the extent to which these variables interact with variables that operate at the landscape scale, and whether there is a hierarchy among the different scales that influences nest-site selection, is unknown. This interaction could be crucial in burrowing birds, which depend heavily on the availability of suitable nesting locations. One representative of this group is the burrowing parrot, Cyanoliseus patagonus that breeds on specific ravines and forms large breeding colonies. At a particular site, breeding aggregations require the concentration of adequate environmental elements for cavity nesting, which are provided by within ravine characteristics. Therefore, intrinsic ravine characteristics should be more important in determining nest site selection compared to landscape level characteristics. Here, we assess this hypothesis by comparing the importance of ravine characteristics operating at different scales on nest-site selection and their interrelation with reproductive success. We quantified 12 characteristics of 105 ravines in their reproductive habitat. For each ravine we quantified morphological variables, distance to resources and disturbance as well as nest number and egg production in order to compare selected and non-selected ravines and determine the interrelationship among variables in explaining ravine differences. In addition, the number of nests and egg production for each reproductive ravine was related to ravine characteristics to assess their relation to reproductive success. We found significant differences between non-reproductive and reproductive ravines in both intrinsic and extrinsic characteristics. The multidimensional environmental gradient of variation between ravines, however, shows that differences are mainly related to intrinsic morphological characteristics followed by extrinsic variables associated to human disturbance. Likewise, within reproductive ravines, intrinsic characteristics are more strongly related to the number of nests. The probability of producing eggs, however, was related only to distance to roads and human settlements. Patterns suggest that C. patagonus mainly selects nesting sites based on intrinsic morphological characteristics of ravines. Scale differences in the importance of ravine characteristics could be a consequence of the particular orography of the breeding habitat. The arrangement of resources is associated to the location of the gullies rather than to individual ravines, determining the spatial availability and disposition of resources and disturbances. Thus, nest selection is influenced by intrinsic characteristics that maximize the fitness of individuals. Scaling in nest-selection is discussed under an optimality approach that partitions patch selection based on foraging theory. PMID:28462019
NASA Astrophysics Data System (ADS)
Nazri, Engku Muhammad; Yusof, Nur Ai'Syah; Ahmad, Norazura; Shariffuddin, Mohd Dino Khairri; Khan, Shazida Jan Mohd
2017-11-01
Prioritizing and making decisions on what student activities to be selected and conducted to fulfill the aspiration of a university as translated in its strategic plan must be executed with transparency and accountability. It is becoming even more crucial, particularly for universities in Malaysia with the recent budget cut imposed by the Malaysian government. In this paper, we illustrated how 0-1 integer programming (0-1 IP) model was implemented to select which activities among the forty activities proposed by the student body of Universiti Utara Malaysia (UUM) to be implemented for the 2017/2018 academic year. Two different models were constructed. The first model was developed to determine the minimum total budget that should be given to the student body by the UUM management to conduct all the activities that can fulfill the minimum targeted number of activities as stated in its strategic plan. On the other hand, the second model was developed to determine which activities to be selected based on the total budget already allocated beforehand by the UUM management towards fulfilling the requirements as set in its strategic plan. The selection of activities for the second model, was also based on the preference of the members of the student body whereby the preference value for each activity was determined using Compromised-Analytical Hierarchy Process. The outputs from both models were compared and discussed. The technique used in this study will be useful and suitable to be implemented by organizations with key performance indicator-oriented programs and having limited budget allocation issues.
Brocato, Terisse A.; Hess, Ryan F.; Moorman, Matthew; ...
2015-10-28
The nitrogen and phosphorus atoms are constituents of some of the most toxic chemical vapors. Nitrogen-phosphorus gas chromatograph detectors (NPDs) rely on selective ionization of such compounds using ionization temperatures typically greater than 600 °C. NPDs have previously been reported to be 7*10 4× and 10 5× more sensitive for nitrogen and phosphorus, respectively, than for carbon. Presented here is an investigation of the structure-based selectivity of a microfabricated nitrogen-phosphorus detector (μNPD). The μNPD presented here is smaller than a dime and can be placed in a system that is 1/100th the size of a commercial NPD. Comparison of responsesmore » of such devices to homologous anilines (p-methoxyaniline, p-fluoroaniline, and aniline) revealed that detection selectivity, determined by the ratio of μNPD to nonselective flame ionization detector (FID) peak areas, is correlated with acid disassociation pK a values for the respective analine. Selectivity was determined to be greatest for p-methoxyaniline, followed by p-fluoroaniline, with aniline having the smallest response. The limit of detection for a nitrogen containing chemical, p-methoxyaniline, using the μNPD was determined to be 0.29 ng compared to 59 ng for a carbon chemical containing no nitrogen or phosphorus, 1,3,5-trimethybenzene. The μNPD presented here has increased detection for nitrogen and phosphorus compared to the FID and with a slight increase in detection of carbon compounds compared to commercial NPD's sensitivity to nitrogen and carbon.« less