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Sample records for additional comparative studies

  1. Influence of Polarization on Carbohydrate Hydration: A Comparative Study Using Additive and Polarizable Force Fields.

    PubMed

    Pandey, Poonam; Mallajosyula, Sairam S

    2016-07-14

    Carbohydrates are known to closely modulate their surrounding solvent structures and influence solvation dynamics. Spectroscopic investigations studying far-IR regions (below 1000 cm(-1)) have observed spectral shifts in the libration band (around 600 cm(-1)) of water in the presence of monosaccharides and polysaccharides. In this paper, we use molecular dynamics simulations to gain atomistic insight into carbohydrate-water interactions and to specifically highlight the differences between additive (nonpolarizable) and polarizable simulations. A total of six monosaccharide systems, α and β anomers of glucose, galactose, and mannose, were studied using additive and polarizable Chemistry at HARvard Macromolecular Mechanics (CHARMM) carbohydrate force fields. Solvents were modeled using three additive water models TIP3P, TIP4P, and TIP5P in additive simulations and polarizable water model SWM4 in polarizable simulations. The presence of carbohydrate has a significant effect on the microscopic water structure, with the effects being pronounced for proximal water molecules. Notably, disruption of the tetrahedral arrangement of proximal water molecules was observed due to the formation of strong carbohydrate-water hydrogen bonds in both additive and polarizable simulations. However, the inclusion of polarization resulted in significant water-bridge occupancies, improved ordered water structures (tetrahedral order parameter), and longer carbohydrate-water H-bond correlations as compared to those for additive simulations. Additionally, polarizable simulations also allowed the calculation of power spectra from the dipole-dipole autocorrelation function, which corresponds to the IR spectra. From the power spectra, we could identify spectral signatures differentiating the proximal and bulk water structures, which could not be captured from additive simulations. PMID:27266974

  2. Comparative study of dimensional accuracy of different impression techniques using addition silicone impression material.

    PubMed

    Penaflor, C F; Semacio, R C; De Las Alas, L T; Uy, H G

    1998-01-01

    This study compared dimensional accuracy of the single, double with spacer, double with cut-out and double mix impression technique using addition silicone impression material. A typhodont containing Ivorine teeth model with six (6) full-crown tooth preparations were used as the positive control. Two stone replication models for each impression technique were made as test materials. Accuracy of the techniques were assessed by measuring four dimensions on the stone dies poured from the impression of the Ivorine teeth model. Results indicated that most of the measurements for the height, width and diameter slightly decreased and a few increased compared with the Ivorine teeth model. The double with cut-out and double mix technique presents the least difference from the master model as compared to the two latter impression techniques. PMID:10202524

  3. Fortification of yogurts with different antioxidant preservatives: A comparative study between natural and synthetic additives.

    PubMed

    Caleja, Cristina; Barros, Lillian; Antonio, Amilcar L; Carocho, Márcio; Oliveira, M Beatriz P P; Ferreira, Isabel C F R

    2016-11-01

    Consumers demand more and more so-called "natural" products and, therefore, the aim of this work was to compare the effects of natural versus synthetic antioxidant preservatives in yogurts. Matricaria recutita L. (chamomile) and Foeniculum vulgare Mill. (fennel) decoctions were tested as natural additives, while potassium sorbate (E202) was used as a synthetic additive. The fortification of yogurts with natural and synthetic antioxidants did not cause significant changes in the yoghurt pH and nutritional value, in comparison with control samples (yogurt without any additive). However, the fortified yogurts showed higher antioxidant activity, mainly the yogurts with natural additives (and among these, the ones with chamomile decoction). Overall, it can be concluded that plant decoctions can be used to develop novel yogurts, by replacing synthetic preservatives and improving the antioxidant properties of the final product, without changing the nutritional profile. PMID:27211646

  4. A clinical comparative study of Cadiax Compact II and intraoral records using wax and addition silicone.

    PubMed

    Torabi, Kianoosh; Pour, Sasan Rasaei; Ahangari, Ahmad Hassan; Ghodsi, Safoura

    2014-01-01

    Evaluation of mandibular movements is necessary to form the occlusal anatomical contour, analyze the temporomandibular joint status, and evaluate the patient's occlusion. This clinical study was conducted to compare the mandibular recording device Cadiax Compact II with routine intraoral records for measuring condylar inclinations. The results showed that the differences between Cadiax and intraoral records were statistically significant for all measurements. Cadiax measurements had a stronger correlation with silicone records. The quantities of recorded Bennett angles were lower and the values of sagittal condylar inclination were higher with Cadiax than with routine intraoral records. PMID:25390868

  5. Additional Language Teaching within the International Baccalaureate Primary Years Programme: A Comparative Study

    ERIC Educational Resources Information Center

    Lebreton, Marlène

    2014-01-01

    The International Baccalaureate Primary Years Programme supports the learning of languages and cultures, but the role of the additional language within this programme is often unclear. There remains a great variability in schools regarding the frequency of lessons and the way that the additional language is taught within the Primary Years…

  6. Comparative study of glycine single crystals with additive of potassium nitrate in different concentration ratios

    NASA Astrophysics Data System (ADS)

    Gujarati, Vivek P.; Deshpande, M. P.; Patel, Kamakshi R.; Chaki, S. H.

    2016-05-01

    Semi-organic crystals of Glycine Potassium Nitrate (GPN) with potential applications in Non linear optics (NLO) were grown using slow evaporation technique. Glycine and Potassium Nitrate were taken in three different concentration ratios of 3:1, 2:1 and 1:1 respectively. We checked the solubility of the material in distilled water at different temperatures and could observe the growth of crystals in 7 weeks time. Purity of the grown crystals was confirmed by Energy Dispersive X-ray Analysis (EDAX) and CHN analysis. GSN Powder X-ray diffraction pattern was recorded to confirm the crystalline nature. To confirm the applications of grown crystals in opto-electronics field, UV-Vis-NIR study was carried out. Dielectric properties of the samples were studied in between the frequency range 1Hz to 100 KHz.

  7. Characterization and comparative study of coal combustion residues from a primary and additional flue gas secondary desulfurization process

    SciTech Connect

    Gomes, S.; Francois, M.; Evrard, O.; Pellissier, C.

    1998-11-01

    An extensive characterization and comparative study was done on two flue gas desulfurization (FGD) residues derived from the same coal. LR residues (originated from Loire/Rhone in the south of Lyon, France) are obtained after a primary desulfurization process (SO{sub 2} is trapped by reaction with CaO at a temperature of about 1100 C), and LM residues (originating from La Maxe, near Metz in the east of France) are obtained after an additional secondary desulfurization process (SO{sub 2} is removed further by reaction with Ca(OH){sub 2} at a temperature of about 120 C). Various and complementary investigation methods were used to determine their chemical, physical, and mineralogical properties: x-ray fluorescence and diffraction, scanning electron microscopy, differential scanning calorimetry, thermogravimetry analysis, granulometric distribution, pycnometric density, BET specific surface area and pH, conductivity measurements, and chemical analysis of their insoluble fraction. The FGD residues contain basically two main components: a silico-aluminous fly ash part and calcic FGD phases. In the LR residues the two components can be considered as independent, whereas they are linked in the LM residues because chemical reactions have occurred, leading to the formation of silico-calcic gel CSH, hydrated aluminate AFm, and AFt phases.

  8. Additional treatment of wastewater reduces endocrine disruption in wild fish--a comparative study of tertiary and advanced treatments.

    PubMed

    Baynes, Alice; Green, Christopher; Nicol, Elizabeth; Beresford, Nicola; Kanda, Rakesh; Henshaw, Alan; Churchley, John; Jobling, Susan

    2012-05-15

    Steroid estrogens are thought to be the major cause of feminization (intersex) in wild fish. Widely used wastewater treatment technologies are not effective at removing these contaminants to concentrations thought to be required to protect aquatic wildlife. A number of advanced treatment processes have been proposed to reduce the concentrations of estrogens entering the environment. Before investment is made in such processes, it is imperative that we compare their efficacy in terms of removal of steroid estrogens and their feminizing effects with other treatment options. This study assessed both steroid removal and intersex induction in adult and early life stage fish (roach, Rutilus rutilus). Roach were exposed directly to either secondary (activated sludge process (ASP)), tertiary (sand filtrated (SF)), or advanced (chlorine dioxide (ClO(2)), granular activated charcoal (GAC)) treated effluents for six months. Surprisingly, both the advanced GAC and tertiary SF treatments (but not the ClO(2) treatment) significantly removed the intersex induction associated with the ASP effluent; this was not predicted by the steroid estrogen measurements, which were higher in the tertiary SF than either the GAC or the ClO(2). Therefore our study highlights the importance of using both biological and chemical analysis when assessing new treatment technologies. PMID:22500691

  9. Additional Routes to Staphylococcus aureus Daptomycin Resistance as Revealed by Comparative Genome Sequencing, Transcriptional Profiling, and Phenotypic Studies

    PubMed Central

    Song, Yang; Rubio, Aileen; Jayaswal, Radheshyam K.; Silverman, Jared A.; Wilkinson, Brian J.

    2013-01-01

    Daptomycin is an extensively used anti-staphylococcal agent due to the rise in methicillin-resistant Staphylococcus aureus, but the mechanism(s) of resistance is poorly understood. Comparative genome sequencing, transcriptomics, ultrastructure, and cell envelope studies were carried out on two relatively higher level (4 and 8 µg/ml−1) laboratory-derived daptomycin-resistant strains (strains CB1541 and CB1540 respectively) compared to their parent strain (CB1118; MW2). Several mutations were found in the strains. Both strains had the same mutations in the two-component system genes walK and agrA. In strain CB1540 mutations were also detected in the ribose phosphate pyrophosphokinase (prs) and polyribonucleotide nucleotidyltransferase genes (pnpA), a hypothetical protein gene, and in an intergenic region. In strain CB1541 there were mutations in clpP, an ATP-dependent protease, and two different hypothetical protein genes. The strain CB1540 transcriptome was characterized by upregulation of cap (capsule) operon genes, genes involved in the accumulation of the compatible solute glycine betaine, ure genes of the urease operon, and mscL encoding a mechanosensitive chanel. Downregulated genes included smpB, femAB and femH involved in the formation of the pentaglycine interpeptide bridge, genes involved in protein synthesis and fermentation, and spa encoding protein A. Genes altered in their expression common to both transcriptomes included some involved in glycine betaine accumulation, mscL, ure genes, femH, spa and smpB. However, the CB1541 transcriptome was further characterized by upregulation of various heat shock chaperone and protease genes, consistent with a mutation in clpP, and lytM and sceD. Both strains showed slow growth, and strongly decreased autolytic activity that appeared to be mainly due to decreased autolysin production. In contrast to previous common findings, we did not find any mutations in phospholipid biosynthesis genes, and it appears there

  10. Biocompatibility of Ricinus communis polymer with addition of calcium carbonate compared to titanium. Experimental study in guinea pigs

    PubMed Central

    Graça, Yorgos Luiz Santos De Salles; Opolski, Ana Cristina; Barboza, Barbara Evelin Gonçalves; Erbano, Bruna Olandoski; Mazzaro, Caroline Cantalejo; Klostermann, Flávia Caroline; Sucharski, Enéas Eduardo; Kubrusly, Luiz Fernando

    2014-01-01

    Objective The aim of the present investigation was to determine whether the difference in inflammatory tissue reaction between the Riccinus communis (castor) polymer with calcium carbonate and the titanium implant is statistically significant. Methods Thirty-two Cavia porcellus were allocated into four groups of eight animals each. We implanted the two types of materials in the retroperitoneal space of all the animals. They were euthanized at 7, 20, 30 and 40 days after surgery, and an histological study of the samples was conducted. Results All implants showed characteristics of chronic inflammation regardless of the material and timepoint of evaluation. There was no statistically significant difference between Pm+CaCO3 and Ti with regard to the presence of granulation tissue, tissue congestion, histiocytes, lymphocytes, neutrophils, giant cells, and fibrosis (P> 0.05). Conclusion The castor oil polymer plus calcium carbonate implant was not statistically different from the titanium implant regarding inflammatory tissue reaction. PMID:25140479

  11. Quality of Life and Neutropenia in Patients with Early Stage Breast Cancer: A Randomized Pilot Study Comparing Additional Treatment with Mistletoe Extract to Chemotherapy Alone

    PubMed Central

    Tröger, Wilfried; Jezdić, Svetlana; Ždrale, Zdravko; Tišma, Nevena; Hamre, Harald J.; Matijašević, Miodrag

    2009-01-01

    Background: Chemotherapy for breast cancer often deteriorates quality of life, augments fatigue, and induces neutropenia. Mistletoe preparations are frequently used by cancer patients in Central Europe. Physicians have reported better quality of life in breast cancer patients additionally treated with mistletoe preparations during chemotherapy. Mistletoe preparations also have immunostimulant properties and might therefore have protective effects against chemotherapy-induced neutropenia. Patients and Methods: We conducted a prospective randomized open label pilot study with 95 patients randomized into three groups. Two groups received Iscador® M special (IMS) or a different mistletoe preparation, respectively, additionally to chemotherapy with six cycles of cyclophosphamide, adriamycin, and 5-fluoro-uracil (CAF). A control group received CAF with no additional therapy. Here we report the comparison IMS (n = 30) vs. control (n = 31). Quality of life including fatigue was assessed with the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire (EORTC-QLQ-C30). Neutropenia was defined as neutrophil counts <1,000/μl and assessed at baseline and one day before each CAF cycle. Results: In the descriptive analysis all 15 scores of the EORTC-QLQ-C30 showed better quality of life in the IMS group compared to the control group. In 12 scores the differences were significant (p < 0.02) and nine scores showed a clinically relevant and significant difference of at least 5 points. Neutropenia occurred in 3/30 IMS patients and in 8/31 control patients (p = 0.182). Conclusions: This pilot study showed an improvement of quality of life by treating breast cancer patients with IMS additionally to CAF. CAF-induced neutropenia showed a trend to lower frequency in the IMS group. PMID:21556248

  12. A prospective, comparative, randomised, double blind study on the efficacy of addition of clonidine to 0.25% bupivacaine in scalp block for supratentorial craniotomies

    PubMed Central

    Wajekar, Anjana Sagar; Oak, Shrikanta P; Shetty, Anita N; Jain, Ruchi A

    2016-01-01

    Background and Aims: Scalp blocks combined with general anaesthesia reduce pin and incision response, along with providing stable perioperative haemodynamics and analgesia. Clonidine has proved to be a valuable additive in infiltrative blocks. We studied the efficacy and safety of addition of clonidine 2 μg/kg to scalp block with 0.25% bupivacaine (Group B) versus plain 0.25% bupivacaine (Group A) for supratentorial craniotomies. Methods: Sixty patients were randomly divided into two groups to receive scalp block: Group A (with 0.25% bupivacaine) and Group B (with 0.25% bupivacaine and clonidine (2 μg/kg). Bilateral scalp block was given immediately after induction. All the patients received propofol based general anaesthesia. Intraoperatively, propofol infusion was maintained at 75 to 100 μg/kg/h up to dura closure and reduced to 50-75 μg/kg/h up to skin closure with atracurium infusion stopped at dura closure. Heart rate (HR) and mean arterial pressure (MAP) were monitored at pin insertion, at 5 minute intervals from incision till dura opening and again at 5 minute interval from dura closure up to skin closure. Fentanyl 0.5 μg/kg was given if a 20% increase in either HR and/or MAP was observed. Postoperative haemodynamics and verbal rating scores (VRS) were recorded. When the VRS score increased above 3, rescue analgesia was given. Any intraoperative haemodynamic complications were noted. Results: Group A showed a significant increase in haemodynamic variables during the perioperative period as compared to group B (P < 0.05). Addition of clonidine 2 μg/kg in the infiltrative block also provided significantly prolonged postoperative analgesia. Conclusions: Addition of clonidine to scalp block provided better perioperative haemodynamic stability and significantly prolonged analgesia. PMID:26962254

  13. Comparative study of GaN mesa etch characteristics in Cl{sub 2} based inductively coupled plasma with Ar and BCl{sub 3} as additive gases

    SciTech Connect

    Rawal, Dipendra Singh Arora, Henika; Sehgal, Bhupender Kumar; Muralidharan, Rangarajan

    2014-05-15

    GaN thin film etching is investigated and compared for mesa formation in inductively coupled plasma (ICP) of Cl{sub 2} with Ar and BCl{sub 3} gas additives using photoresist mask. Etch characteristics are studied as a function of ICP process parameters, viz., ICP power, radio frequency (RF) power, and chamber pressure at fixed total flow rate. The etch rate at each ICP/RF power is 0.1–0.2 μm/min higher for Cl{sub 2}/Ar mixture mainly due to higher Cl dissociation efficiency of Ar additive that readily provides Cl ion/radical for reaction in comparison to Cl{sub 2}/BCl{sub 3} mixture. Cl{sub 2}/Ar mixture also leads to better photoresist mask selectivity. The etch-induced roughness is investigated using atomic force microscopy. Cl{sub 2}/Ar etching has resulted in lower root-mean-square roughness of GaN etched surface in comparison to Cl{sub 2}/BCl{sub 3} etching due to increased Ar ion energy and flux with ICP/RF power that enhances the sputter removal of etch product. The GaN surface damage after etching is also evaluated using room temperature photoluminescence and found to be increasing with ICP/RF power for both the etch chemistries with higher degree of damage in Cl{sub 2}/BCl{sub 3} etching under same condition.

  14. A Comparative Study of Listening Comprehension Measures in English as an Additional Language and Native English-Speaking Primary School Children

    ERIC Educational Resources Information Center

    McKendry, Mairead Grainne; Murphy, Victoria A.

    2011-01-01

    The aim of this study was to investigate the suitability of different measures of listening comprehension for Years 2, 3 and 4 children with English as an additional language (EAL). Non-standardised uses of reading comprehension measures are often employed as proxy measures of listening comprehension, i.e. for purposes for which they were not…

  15. Five-year follow-up of patients with early stage breast cancer after a randomized study comparing additional treatment with viscum album (L.) extract to chemotherapy alone.

    PubMed

    Tröger, Wilfried; Zdrale, Zdravko; Stanković, Nikola; Matijašević, Miodrag

    2012-01-01

    Additional therapy with extracts of Viscum album [L.] (VaL) increases the quality of life of patients suffering from early stage breast cancer during chemotherapy. In the current study patients received chemotherapy, consisting of six cycles of cyclophosphamide, anthracycline, and 5-Fluoro-Uracil (CAF). Two groups also received one of two VaL extracts differing in their preparation as subcutaneous injection three times per week. A control group received CAF with no additional therapy. Six of 28 patients in one of the VaL groups and eight of 29 patients in the control group developed relapse or metastasis within 5 years. Subgroup analysis for hormone- and radiotherapy also showed no difference between groups. Additional VaL therapy during chemotherapy of early stage breast cancer patients appears not to influence the frequency of relapse or metastasis within 5 years. PMID:23150723

  16. Five-Year Follow-Up of Patients with Early Stage Breast Cancer After a Randomized Study Comparing Additional Treatment with Viscum Album (L.) Extract to Chemotherapy Alone

    PubMed Central

    Tröger, Wilfried; Ždrale, Zdravko; Stanković, Nikola; Matijašević, Miodrag

    2012-01-01

    Additional therapy with extracts of Viscum album [L.] (VaL) increases the quality of life of patients suffering from early stage breast cancer during chemotherapy. In the current study patients received chemotherapy, consisting of six cycles of cyclophosphamide, anthracycline, and 5-Fluoro-Uracil (CAF). Two groups also received one of two VaL extracts differing in their preparation as subcutaneous injection three times per week. A control group received CAF with no additional therapy. Six of 28 patients in one of the VaL groups and eight of 29 patients in the control group developed relapse or metastasis within 5 years. Subgroup analysis for hormone- and radiotherapy also showed no difference between groups. Additional VaL therapy during chemotherapy of early stage breast cancer patients appears not to influence the frequency of relapse or metastasis within 5 years. PMID:23150723

  17. Multi-site study of additive genetic effects on fractional anisotropy of cerebral white matter: comparing meta and mega analytical approaches for data pooling

    PubMed Central

    Kochunov, Peter; Jahanshad, Neda; Sprooten, Emma; Nichols, Thomas E.; Mandl, René C.; Almasy, Laura; Booth, Tom; Brouwer, Rachel M.; Curran, Joanne E.; de Zubicaray, Greig I.; Dimitrova, Rali; Duggirala, Ravi; Fox, Peter T.; Hong, L. Elliot; Landman, Bennett A.; Lemaitre, Hervé; Lopez, Lorna; Martin, Nicholas G.; McMahon, Katie L.; Mitchell, Braxton D.; Olvera, Rene L.; Peterson, Charles P.; Starr, John M.; Sussmann, Jessika E.; Toga, Arthur W.; Wardlaw, Joanna M.; Wright, Margaret J.; Wright, Susan N.; Bastin, Mark E.; McIntosh, Andrew M.; Boomsma, Dorret I.; Kahn, René S.; den Braber, Anouk; de Geus, Eco JC; Deary, Ian J.; Hulshoff Pol, Hilleke E.; Williamson, Douglas E.; Blangero, John; van ’t Ent, Dennis; Thompson, Paul M.; Glahn, David C.

    2014-01-01

    Combining datasets across independent studies can boost statistical power by increasing the numbers of observations and can achieve more accurate estimates of effect sizes. This is especially important for genetic studies where a large number of observations are required to obtain sufficient power to detect and replicate genetic effects. There is a need to develop and evaluate methods for joint-analytical analyses of rich datasets collected in imaging genetics studies. The ENIGMA-DTI consortium is developing and evaluating approaches for obtaining pooled estimates of heritability through meta-and mega-genetic analytical approaches, to estimate the general additive genetic contributions to the intersubject variance in fractional anisotropy (FA) measured from diffusion tensor imaging (DTI). We used the ENIGMA-DTI data harmonization protocol for uniform processing of DTI data from multiple sites. We evaluated this protocol in five family-based cohorts providing data from a total of 2248 children and adults (ages: 9–85) collected with various imaging protocols. We used the imaging genetics analysis tool, SOLAR-Eclipse, to combine twin and family data from Dutch, Australian and Mexican-American cohorts into one large “mega-family”. We showed that heritability estimates may vary from one cohort to another. We used two meta-analytical (the sample-size and standard-error weighted) approaches and a mega-genetic analysis to calculate heritability estimates across-population. We performed leave-one-out analysis of the joint estimates of heritability, removing a different cohort each time to understand the estimate variability. Overall, meta- and mega-genetic analyses of heritability produced robust estimates of heritability. PMID:24657781

  18. Multi-site study of additive genetic effects on fractional anisotropy of cerebral white matter: Comparing meta and megaanalytical approaches for data pooling.

    PubMed

    Kochunov, Peter; Jahanshad, Neda; Sprooten, Emma; Nichols, Thomas E; Mandl, René C; Almasy, Laura; Booth, Tom; Brouwer, Rachel M; Curran, Joanne E; de Zubicaray, Greig I; Dimitrova, Rali; Duggirala, Ravi; Fox, Peter T; Hong, L Elliot; Landman, Bennett A; Lemaitre, Hervé; Lopez, Lorna M; Martin, Nicholas G; McMahon, Katie L; Mitchell, Braxton D; Olvera, Rene L; Peterson, Charles P; Starr, John M; Sussmann, Jessika E; Toga, Arthur W; Wardlaw, Joanna M; Wright, Margaret J; Wright, Susan N; Bastin, Mark E; McIntosh, Andrew M; Boomsma, Dorret I; Kahn, René S; den Braber, Anouk; de Geus, Eco J C; Deary, Ian J; Hulshoff Pol, Hilleke E; Williamson, Douglas E; Blangero, John; van 't Ent, Dennis; Thompson, Paul M; Glahn, David C

    2014-07-15

    Combining datasets across independent studies can boost statistical power by increasing the numbers of observations and can achieve more accurate estimates of effect sizes. This is especially important for genetic studies where a large number of observations are required to obtain sufficient power to detect and replicate genetic effects. There is a need to develop and evaluate methods for joint-analytical analyses of rich datasets collected in imaging genetics studies. The ENIGMA-DTI consortium is developing and evaluating approaches for obtaining pooled estimates of heritability through meta-and mega-genetic analytical approaches, to estimate the general additive genetic contributions to the intersubject variance in fractional anisotropy (FA) measured from diffusion tensor imaging (DTI). We used the ENIGMA-DTI data harmonization protocol for uniform processing of DTI data from multiple sites. We evaluated this protocol in five family-based cohorts providing data from a total of 2248 children and adults (ages: 9-85) collected with various imaging protocols. We used the imaging genetics analysis tool, SOLAR-Eclipse, to combine twin and family data from Dutch, Australian and Mexican-American cohorts into one large "mega-family". We showed that heritability estimates may vary from one cohort to another. We used two meta-analytical (the sample-size and standard-error weighted) approaches and a mega-genetic analysis to calculate heritability estimates across-population. We performed leave-one-out analysis of the joint estimates of heritability, removing a different cohort each time to understand the estimate variability. Overall, meta- and mega-genetic analyses of heritability produced robust estimates of heritability. PMID:24657781

  19. Addition polyimide end cap study

    NASA Technical Reports Server (NTRS)

    St.clair, T. L.

    1980-01-01

    The characterization of addition polyimides with various end caps for adhesive applications at 120-250 C environments is discussed. Oligometric polyimides were prepared from 3,3',4,4'-benzophenone tetracarboxylic dianhydride and 3,3'-methylenedianiline which were end-capped with functionally reactive moities which cause crosslinking when the oligomers are heated to 200-400 C. The syntheses of the oligomers are outlined. The thermolysis of the oligomers was studied by differential scanning calorimetry and the resulting polymers were characterized by differential thermal analysis and adhesive performance. The adhesive data include lap shear strengths on titanium 6-4 adherends both before and after aging for 1000 hours at 121 C and/or 232 C.

  20. Comparative Packaging Study

    NASA Technical Reports Server (NTRS)

    Perchonok, Michele; Antonini, David

    2008-01-01

    This viewgraph presentation describes a comparative packaging study for use on long duration space missions. The topics include: 1) Purpose; 2) Deliverables; 3) Food Sample Selection; 4) Experimental Design Matrix; 5) Permeation Rate Comparison; and 6) Packaging Material Information.

  1. Operations dashboard: comparative study

    NASA Astrophysics Data System (ADS)

    Ramly, Noor Nashriq; Ismail, Ahmad Zuhairi; Aziz, Mohd Haris; Ahmad, Nurul Haszeli

    2011-10-01

    In this present days and age, there are increasing needs for companies to monitor application and infrastructure health. Apart from having proactive measures to secure their application and infrastructure, many see monitoring dashboards as crucial investment in disaster preparedness. As companies struggle to find the best solution to cater for their needs and interest for monitoring their application and infrastructure's health, this paper summarizes the studies made on several known off-the-shelf operations dashboard and in-house developed dashboard. A few criteria of good dashboard are collected from previous studies carried out by several researchers and rank them according to importance and business needs. The finalized criteria that will be discussed in later sections are data visualization, performance indicator, dashboard personalization, audit capability and alert/ notification. Comparative studies between several popular dashboards were then carried out to determine whether they met these criteria that we derived from the first exercise. The findings hopefully can be used to educate and provide an overview of selecting the best IT application and infrastructure operations dashboard that suit business needs, thus become the main contribution of this paper.

  2. Effectiveness of additional self-care acupressure for women with menstrual pain compared to usual care alone: using stakeholder engagement to design a pragmatic randomized trial and study protocol

    PubMed Central

    2013-01-01

    Background Self-care acupressure might be successful in treating menstrual pain, which is common among young women. There is a need for comparative effectiveness research with stakeholder engagement in all phases seeking to address the needs of decision-makers. Our aim was to design a study on the effectiveness of additional self-care acupressure for menstrual pain comparing usual care alone using different methods of stakeholder engagement. Methods The study was designed using multiple mixed methods for stakeholder engagement. Based on the results of a survey and focus group discussion, a stakeholder advisory group developed the study design. Results Stakeholder engagement resulted in a two-arm pragmatic randomized trial. Two hundred and twenty women aged 18 to 25 years with menstrual pain will be included in the study. Outcome measurement will be done using electronic questionnaires provided by a study specific mobile application (App). Primary outcome will be the mean pain intensity at the days of pain during the third menstruation after therapy start. Conclusion Stakeholder engagement helped to develop a study design that better serves the needs of decision makers, including an App as a modern tool for both intervention and data collection in a young target group. Trial registration Clinicaltrials.gov identifier http://NCT01582724 PMID:24499425

  3. Comparing Number Lines and Touch Points to Teach Addition Facts to Students with Autism

    ERIC Educational Resources Information Center

    Cihak, David F.; Foust, Jennifer L.

    2008-01-01

    Three elementary students with autism were taught single-digit addition problem-solving skills using number and touch-point strategies. Prior to the study, all students were unable to correctly calculate single-digit addition problems. An alternating-treatments design was used to compare the acquisition performance of single-digit addition…

  4. Comparative Packaging Study

    NASA Technical Reports Server (NTRS)

    Perchonok, Michele H.; Oziomek, Thomas V.

    2009-01-01

    Future long duration manned space flights beyond low earth orbit will require the food system to remain safe, acceptable and nutritious. Development of high barrier food packaging will enable this requirement by preventing the ingress and egress of gases and moisture. New high barrier food packaging materials have been identified through a trade study. Practical application of this packaging material within a shelf life test will allow for better determination of whether this material will allow the food system to meet given requirements after the package has undergone processing. The reason to conduct shelf life testing, using a variety of packaging materials, stems from the need to preserve food used for mission durations of several years. Chemical reactions that take place during longer durations may decrease food quality to a point where crew physical or psychological well-being is compromised. This can result in a reduction or loss of mission success. The rate of chemical reactions, including oxidative rancidity and staling, can be controlled by limiting the reactants, reducing the amount of energy available to drive the reaction, and minimizing the amount of water available. Water not only acts as a media for microbial growth, but also as a reactant and means by which two reactants may come into contact with each other. The objective of this study is to evaluate three packaging materials for potential use in long duration space exploration missions.

  5. Additives

    NASA Technical Reports Server (NTRS)

    Smalheer, C. V.

    1973-01-01

    The chemistry of lubricant additives is discussed to show what the additives are chemically and what functions they perform in the lubrication of various kinds of equipment. Current theories regarding the mode of action of lubricant additives are presented. The additive groups discussed include the following: (1) detergents and dispersants, (2) corrosion inhibitors, (3) antioxidants, (4) viscosity index improvers, (5) pour point depressants, and (6) antifouling agents.

  6. Comparative study of the effect of pharmaceutical additives on the elimination of antibiotic activity during the treatment of oxacillin in water by the photo-Fenton, TiO2-photocatalysis and electrochemical processes.

    PubMed

    Serna-Galvis, Efraim A; Silva-Agredo, Javier; Giraldo, Ana L; Flórez-Acosta, Oscar A; Torres-Palma, Ricardo A

    2016-01-15

    Synthetic pharmaceutical effluents loaded with the β-lactam antibiotic oxacillin were treated using advanced oxidation processes (the photo-Fenton system and TiO2 photocatalysis) and chloride mediated electrochemical oxidation (with Ti/IrO2 anodes). Combinations of the antibiotic with excipients (mannitol or tartaric acid), an active ingredient (calcium carbonate, i.e. bicarbonate ions due to the pH) and a cleaning agent (sodium lauryl ether sulfate) were considered. Additionally, urban wastewater that had undergone biological treatment was doped with oxacillin and treated with the tested systems. The evolution of antimicrobial activity was monitored as a parameter of processes efficiency. Although the two advanced oxidation processes (AOPs) differ only in the way they produce OH, marked differences were observed between them. There were also differences between the AOPs and the electrochemical system. Interestingly, each additive had a different effect on each treatment. For water loaded with mannitol, electrochemical treatment was the most suitable option because the additive did not significantly affect the efficiency of the system. Due to the formation of a complex with Fe(3+), tartaric acid accelerated the elimination of antibiotic activity during the photo-Fenton process. For TiO2 photocatalysis, the presence of bicarbonate ions contributed to antibiotic activity elimination through the possible formation of carbonate and bicarbonate radicals. Sodium lauryl ether sulfate negatively affected all of the processes. However, due to the higher selectivity of HOCl compared with OH, electrochemical oxidation showed the least inhibited efficiency. For the urban wastewater doped with oxacillin, TiO2 photocatalysis was the most efficient process. These results will help select the most suitable technology for the treatment of water polluted with β-lactam antibiotics. PMID:26479916

  7. Additional EIPC Study Analysis. Final Report

    SciTech Connect

    Hadley, Stanton W; Gotham, Douglas J.; Luciani, Ralph L.

    2014-12-01

    Between 2010 and 2012 the Eastern Interconnection Planning Collaborative (EIPC) conducted a major long-term resource and transmission study of the Eastern Interconnection (EI). With guidance from a Stakeholder Steering Committee (SSC) that included representatives from the Eastern Interconnection States Planning Council (EISPC) among others, the project was conducted in two phases. Phase 1 involved a long-term capacity expansion analysis that involved creation of eight major futures plus 72 sensitivities. Three scenarios were selected for more extensive transmission- focused evaluation in Phase 2. Five power flow analyses, nine production cost model runs (including six sensitivities), and three capital cost estimations were developed during this second phase. The results from Phase 1 and 2 provided a wealth of data that could be examined further to address energy-related questions. A list of 14 topics was developed for further analysis. This paper brings together the earlier interim reports of the first 13 topics plus one additional topic into a single final report.

  8. Structure Property Studies for Additively Manufactured Parts

    SciTech Connect

    Milenski, Helen M; Schmalzer, Andrew Michael; Kelly, Daniel

    2015-08-17

    Since the invention of modern Additive Manufacturing (AM) processes engineers and designers have worked hard to capitalize on the unique building capabilities that AM allows. By being able to customize the interior fill of parts it is now possible to design components with a controlled density and customized internal structure. The creation of new polymers and polymer composites allow for even greater control over the mechanical properties of AM parts. One of the key reasons to explore AM, is to bring about a new paradigm in part design, where materials can be strategically optimized in a way that conventional subtractive methods cannot achieve. The two processes investigated in my research were the Fused Deposition Modeling (FDM) process and the Direct Ink Write (DIW) process. The objectives of the research were to determine the impact of in-fill density and morphology on the mechanical properties of FDM parts, and to determine if DIW printed samples could be produced where the filament diameter was varied while the overall density remained constant.

  9. Modeled heating and surface erosion comparing motile (gas borne) and stationary (surface coating) inert particle additives

    SciTech Connect

    Buckingham, A.C.; Siekhaus, W.J.

    1982-09-27

    The unsteady, non-similar, chemically reactive, turbulent boundary layer equations are modified for gas plus dispersed solid particle mixtures, for gas phase turbulent combustion reactions and for heterogeneous gas-solid surface erosive reactions. The exterior (ballistic core) edge boundary conditions for the solutions are modified to include dispersed particle influences on core propellant combustion-generated turbulence levels, combustion reactants and products, and reaction-induced, non-isentropic mixture states. The wall surface (in this study it is always steel) is considered either bare or coated with a fixed particle coating which is conceptually non-reactive, insulative, and non-ablative. Two families of solutions are compared. These correspond to: (1) consideration of gas-borne, free-slip, almost spontaneously mobile (motile) solid particle additives which influence the turbulent heat transfer at the uncoated steel surface and, in contrast, (2) consideration of particle-free, gas phase turbulent heat transfer to the insulated surface coated by stationary particles. Significant differences in erosive heat transfer are found in comparing the two families of solutions over a substantial range of interior ballistic flow conditions. The most effective influences on reducing erosive heat transfer appear to favor mobile, gas-borne particle additives.

  10. Comparative Shock Response of Additively Manufactured Versus Conventionally Wrought 304L Stainless Steel*

    NASA Astrophysics Data System (ADS)

    Wise, J. L.; Adams, D. P.; Nishida, E. E.; Song, B.; Maguire, M. C.; Carroll, J.; Reedlunn, B.; Bishop, J. E.

    2015-06-01

    Gas-gun experiments have probed the compression and release behavior of impact-loaded 304L stainless steel specimens machined from additively manufactured (AM) blocks as well as baseline ingot-derived bar stock. The AM technology allows direct fabrication of metal parts. For the present study, a velocity interferometer (VISAR) measured the time-resolved motion of samples subjected to one-dimensional (i.e., uniaxial strain) shock compression to peak stresses ranging from 0.2 to 7.5 GPa. The acquired wave-profile data have been analyzed to determine the comparative Hugoniot Elastic Limit (HEL), Hugoniot equation of state, spall strength, and high-pressure yield strength of the AM and conventional materials. Observed differences in shock loading and unloading characteristics for the two 304L source variants have been correlated to complementary Kolsky bar results for compressive and tensile testing at lower strain rates. The effects of composition, porosity, microstructure (e.g., grain size and morphology), residual stress, and sample axis orientation relative to the additive manufacturing deposition trajectory have been assessed to explain differences between the AM and baseline 304L dynamic mechanical properties. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under Contract DE-AC04-94AL85000.

  11. A randomized trial to compare the safety of rivaroxaban vs aspirin in addition to either clopidogrel or ticagrelor in acute coronary syndrome: The design of the GEMINI-ACS-1 phase II study.

    PubMed

    Povsic, Thomas J; Roe, Matthew T; Ohman, Erik Magnus; Steg, Philippe Gabriel; James, Stefan; Plotnikov, Alexei; Mundl, Hardi; Welsh, Robert; Bode, Christoph; Gibson, Charles Michael

    2016-04-01

    Dual antiplatelet therapy (DAPT), the combination of aspirin and a P2Y12 inhibitor, given for 12 months remains the standard of care after presentation with acute coronary syndrome (ACS) because it has been shown to be associated with a significant reduction in ischemic events compared with aspirin monotherapy. The factor Xa inhibitor rivaroxaban was shown to be associated with a significant reduction in the composite of cardiovascular death, myocardial infarction, and stroke, and resulted in a nominal reduction in cardiovascular death, when added to background DAPT in the ATLAS ACS 2-TIMI 51 trial; however, there was excessive bleeding with this "triple-therapy" approach. The combination of rivaroxaban with P2Y12 inhibition in a "dual-pathway" approach may be an effective therapeutic regimen for the treatment of ACS, given the known importance of P2Y12 inhibition after stenting and intriguing data that the combination of an anticoagulant with clopidogrel after stenting in patients with atrial fibrillation appears an attractive option to this patient population. GEMINI-ACS-1 is a prospective, randomized, double-dummy, double-blind, active-controlled trial that will assess the safety of dual antithrombotic therapy (rivaroxaban [2.5 mg twice daily] + P2Y12 inhibitor) as compared with DAPT (aspirin [100 mg] + P2Y12 inhibitor) within 10 days of an ACS event in 3,000 patients. Patients will be randomized in a 1:1 ratio stratified by intended P2Y12 inhibitor use (clopidogrel 75 mg daily or ticagrelor 90 mg twice daily), with 1500 patients expected in each P2Y12 inhibitor strata. The primary end point is Thrombolysis in Myocardial Infarction clinically significant bleeding (major, minor, or requiring medical attention). The exploratory efficacy determination will be a composite of cardiovascular death, myocardial infarction, ischemic stroke, and stent thrombosis. GEMINI-ACS-1 will assess the safety and feasibility of dual antithrombotic therapy with rivaroxaban and a P2Y

  12. Sex work: a comparative study.

    PubMed

    McCarthy, Bill; Benoit, Cecilia; Jansson, Mikael

    2014-10-01

    Explanations of adult involvement in sex work typically adopt one of two approaches. One perspective highlights a variety of negative experiences in childhood and adolescence, including physical and sexual abuse, family instability, poverty, associations with "pimps" and other exploiters, homelessness, and drug use. An alternative account recognizes that some of these factors may be involved, but underscores the contribution of more immediate circumstances, such as current economic needs, human capital, and employment opportunities. Prior research offers a limited assessment of these contrasting claims: most studies have focused exclusively on people working in the sex industry and they have not assessed the independent effects of life course variables central to these two perspectives. We add to this literature with an analysis that drew on insights from life course and life-span development theories and considered the contributions of factors from childhood, adolescence, and adulthood. Our comparative approach examined predictors of employment in sex work relative to two other low-income service or care work occupations: food and beverage serving and barbering and hairstyling. Using data from a study of almost 600 workers from two cities, one in Canada and the other in the United States, we found that both immediate circumstances and negative experiences from early life are related to current sex work involvement: childhood poverty, abuse, and family instability were independently associated with adult sex work, as were limited education and employment experience, adult drug use, and marital status. PMID:24671729

  13. Additional Treatments Offer Little Benefit for Pancreatic Cancer: Study

    MedlinePlus

    ... 158633.html Additional Treatments Offer Little Benefit for Pancreatic Cancer: Study Neither extra chemotherapy drug nor add-on ... 2016 (HealthDay News) -- Additional treatments for locally advanced pancreatic cancer don't appear to boost survival, a new ...

  14. Comparative Studies of Acculturative Stress.

    ERIC Educational Resources Information Center

    Berry, J. W.; And Others

    1987-01-01

    Studies of acculturative stress are reported from Canada. The reduction in health status among people undergoing acculturation has psychological, somatic, and social aspects. The stress varies across types of groups and individual differences. Further study is needed to determine variations across host societies. (VM)

  15. Comparative Studies in Special Education.

    ERIC Educational Resources Information Center

    Mazurek, Kas, Ed.; Winzer, Margret A., Ed.

    This text presents 26 case studies which examine special education provisions for children in the world today. The reports focus on the current state of special education in selected nations and major issues and controversies in the field of special education within those nations. Each case study addresses the following themes: (1) prevalence of…

  16. A Study of Additional Costs of Second Language Instruction.

    ERIC Educational Resources Information Center

    McEwen, Nelly

    A study was conducted whose primary aim was to identify and explain additional costs incurred by Alberta, Canada school jurisdictions providing second language instruction in 1980. Additional costs were defined as those which would not have been incurred had the second language program not been in existence. Three types of additional costs were…

  17. Comparative study of heart sound localization algorithms

    NASA Astrophysics Data System (ADS)

    Moukadem, A.; Dieterlen, A.; Hueber, N.; Brandt, C.; Raymond, P.

    2011-05-01

    The purpose of this document is to present a comparative study of five algorithms of heart sound localization, one of which, is a method based on radial basis function networks applied in a novel approach. The advantages and disadvantages of each method are evaluated according to a data base of 50 subjects in which there are 25 healthy subjects selected from the University Hospital of Strasbourg (HUS) and from theMARS500 project (Moscow) and 25 subjects with cardiac pathologies selected from the HUS. This study is made under the control of an experienced cardiologist. The performance of each method is evaluated by calculating the area under a receiver operating curve (AUC) and the robustness is shown against different levels of additive white Gaussian noise.

  18. A Comparative Study of Mammalian Diversification Pattern

    PubMed Central

    Yu, Wenhua; Xu, Junxiao; Wu, Yi; Yang, Guang

    2012-01-01

    Although mammals have long been regarded as a successful radiation, the diversification pattern among the clades is still poorly known. Higher-level phylogenies are conflicting and comprehensive comparative analyses are still lacking. Using a recently published supermatrix encompassing nearly all extant mammalian families and a novel comparative likelihood approach (MEDUSA), the diversification pattern of mammalian groups was examined. Both order- and family-level phylogenetic analyses revealed the rapid radiation of Boreoeutheria and Euaustralidelphia in the early mammalian history. The observation of a diversification burst within Boreoeutheria at approximately 100 My supports the Long Fuse model in elucidating placental diversification progress, and the rapid radiation of Euaustralidelphia suggests an important role of biogeographic dispersal events in triggering early Australian marsupial rapid radiation. Diversification analyses based on family-level diversity tree revealed seven additional clades with exceptional diversification rate shifts, six of which represent accelerations in net diversification rate as compared to the background pattern. The shifts gave origin to the clades Muridae+Cricetidae, Bovidae+Moschidae+Cervidae, Simiiformes, Echimyidae, Odontoceti (excluding Physeteridae+Kogiidae+Platanistidae), Macropodidae, and Vespertilionidae. Moderate to high extinction rates from background and boreoeutherian diversification patterns indicate the important role of turnovers in shaping the heterogeneous taxonomic richness observed among extant mammalian groups. Furthermore, the present results emphasize the key role of extinction on erasing unusual diversification signals, and suggest that further studies are needed to clarify the historical radiation of some mammalian groups for which MEDUSA did not detect exceptional diversification rates. PMID:22457604

  19. A comparative analysis of British and Taiwanese students' conceptual and procedural knowledge of fraction addition

    NASA Astrophysics Data System (ADS)

    Li, Hui-Chuan

    2014-10-01

    This study examines students' procedural and conceptual achievement in fraction addition in England and Taiwan. A total of 1209 participants (561 British students and 648 Taiwanese students) at ages 12 and 13 were recruited from England and Taiwan to take part in the study. A quantitative design by means of a self-designed written test is adopted as central to the methodological considerations. The test has two major parts: the concept part and the skill part. The former is concerned with students' conceptual knowledge of fraction addition and the latter is interested in students' procedural competence when adding fractions. There were statistically significant differences both in concept and skill parts between the British and Taiwanese groups with the latter having a higher score. The analysis of the students' responses to the skill section indicates that the superiority of Taiwanese students' procedural achievements over those of their British peers is because most of the former are able to apply algorithms to adding fractions far more successfully than the latter. Earlier, Hart [1] reported that around 30% of the British students in their study used an erroneous strategy (adding tops and bottoms, for example, 2/3 + 1/7 = 3/10) while adding fractions. This study also finds that nearly the same percentage of the British group remained using this erroneous strategy to add fractions as Hart found in 1981. The study also provides evidence to show that students' understanding of fractions is confused and incomplete, even those who are successfully able to perform operations. More research is needed to be done to help students make sense of the operations and eventually attain computational competence with meaningful grounding in the domain of fractions.

  20. Rare HLA Drive Additional HIV Evolution Compared to More Frequent Alleles

    PubMed Central

    Lockhart, David W.; Listgarten, Jennifer; Maley, Stephen N.; Kadie, Carl; Learn, Gerald H.; Nickle, David C.; Heckerman, David E.; Deng, Wenjie; Brander, Christian; Ndung'u, Thumbi; Coovadia, Hoosen; Goulder, Philip J.R.; Korber, Bette T.; Walker, Bruce D.; Mullins, James I.

    2009-01-01

    Abstract HIV-1 can evolve HLA-specific escape variants in response to HLA-mediated cellular immunity. HLA alleles that are common in the host population may increase the frequency of such escape variants at the population level. When loss of viral fitness is caused by immune escape variation, these variants may revert upon infection of a new host who does not have the corresponding HLA allele. Furthermore, additional escape variants may appear in response to the nonconcordant HLA alleles. Because individuals with rare HLA alleles are less likely to be infected by a partner with concordant HLA alleles, viral populations infecting hosts with rare HLA alleles may undergo a greater amount of evolution than those infecting hosts with common alleles due to the loss of preexisting escape variants followed by new immune escape. This hypothesis was evaluated using maximum likelihood phylogenetic trees of each gene from 272 full-length HIV-1 sequences. Recent viral evolution, as measured by the external branch length, was found to be inversely associated with HLA frequency in nef (p < 0.02), env (p < 0.03), and pol (p ≤ 0.05), suggesting that rare HLA alleles provide a disproportionate force driving viral evolution compared to common alleles, likely due to the loss of preexisting escape variants during early stages postinfection. PMID:19327049

  1. Additive Manufacturing in Production: A Study Case Applying Technical Requirements

    NASA Astrophysics Data System (ADS)

    Ituarte, Iñigo Flores; Coatanea, Eric; Salmi, Mika; Tuomi, Jukka; Partanen, Jouni

    Additive manufacturing (AM) is expanding the manufacturing capabilities. However, quality of AM produced parts is dependent on a number of machine, geometry and process parameters. The variability of these parameters affects the manufacturing drastically and therefore standardized processes and harmonized methodologies need to be developed to characterize the technology for end use applications and enable the technology for manufacturing. This research proposes a composite methodology integrating Taguchi Design of Experiments, multi-objective optimization and statistical process control, to optimize the manufacturing process and fulfil multiple requirements imposed to an arbitrary geometry. The proposed methodology aims to characterize AM technology depending upon manufacturing process variables as well as to perform a comparative assessment of three AM technologies (Selective Laser Sintering, Laser Stereolithography and Polyjet). Results indicate that only one machine, laser-based Stereolithography, was feasible to fulfil simultaneously macro and micro level geometrical requirements but mechanical properties were not at required level. Future research will study a single AM system at the time to characterize AM machine technical capabilities and stimulate pre-normative initiatives of the technology for end use applications.

  2. Water Ice in Comets: A Comparative Study

    NASA Astrophysics Data System (ADS)

    Protopapa, Silvia; Sunshine, J.; Feaga, L. M.; Kelley, M. S.; A'Hearn, M. F.; Farnham, T.; DIXI Team

    2013-06-01

    Processes involving the sublimation of volatiles dominate cometary activity and drive the release of ancient material from within the nucleus into the coma. As comets are kept cold for most of their history, they contain the least processed primordial materials that accumulated into the giant planets. In addition, comets may have delivered their ices and organics to the primitive Earth. The Deep Impact eXtended Investigation (DIXI) to comet Hartley 2 revealed a highly active comet with bright icy-rich jets. We present a detailed characterization of the composition and texture of the ices and refractories in the inner-most coma of Hartley 2, closer than a few kilometers from the surface. This analysis is conducted using laboratory measurements of optical constants of cometary analog materials. We also discuss the implications of these findings on the accretion process that led to the formation of cometary nuclei and therefore of planets. The physical makeup of the ice grains in comet Hartley 2 is compared with that of water ice in the interior, surface, and coma of other comets (e.g., 9P/Tempel 1, C/2002 T7 (LINEAR), 17P/Holmes). Through this comparative study, we investigate how ice is redistributed from the interior to the surface and ultimately into the coma of comets.

  3. The Illiteracy Myth. A Comparative Study of Prisoner Literacy Abilities.

    ERIC Educational Resources Information Center

    Black, Stephen; And Others

    Illiteracy is seen to be a feature of the Australian prisoner population. This belief has remained largely untested. A study compared the literacy abilities of prisoners to those found in the adult general population. Additionally, the study compared male and female prisoner literacy abilities. Assessments were made on a profile of literacy…

  4. Comparative characterization of the physicochemical behavior and skin permeation of extruded DPPC liposomes modified by selected additives.

    PubMed

    Biruss, Babette; Valenta, Claudia

    2007-08-01

    The purpose of the present study was to analyze the influence of cholesterol (CHOL), stearylamine (SA), dicetyl phosphate (DCP), and xylenesulfonic acid sodium salt (SXS) in extruded DPPC (1,2-dipalmitoyl-sn-glycero-3-phosphocholine) liposomes on their size, shape, and skin permeation of the model drug progesterone. The additives were incorporated in different molar ratios in relation to the phospholipid content. It could be proven that different molar ratios of the additives to lipids were able to modify liposome size, zeta potential, and the characteristic phase transition temperature of the lipids. In standard skin diffusion experiments SA and SXS increased the progesterone permeation two- to fourfold respectively after 48 h compared to the control. PMID:17301964

  5. Dexmedetomidine as an additive to local anesthetics compared with intravenous dexmedetomidine in peribulbar block for cataract surgery

    PubMed Central

    Abdelhamid, AM; Mahmoud, AAA; Abdelhaq, MM; Yasin, HM; Bayoumi, ASM

    2016-01-01

    Background: No studies compared parenteral dexmedetomidine with its use as an adjuvant to ophthalmic block. We compared between adding dexmedetomidine to bupivacaine in peribulbar block and intravenous (IV) dexmedetomidine during peribulbar block for cataract surgery. Materials and Methods: A prospective, randomized, double-blind study on 90 patients for cataract surgery under peribulbar anesthesia. Study included three groups; all patients received 10 ml of peribulbar anesthesia and IV infusion of drugs as follows: Group I: Received a mixture of bupivacaine 0.5% (4.5 ml) + lidocaine 2% (4.5 ml) + normal saline (1 ml) + 150 IU hyaluronidase + IV infusion of normal saline, Group II: Received mixture of bupivacaine 0.5% (4.5 ml) + lidocaine 2% (4.5 ml) + dexmedetomidine 50 μg (1 ml) +150 IU hyaluronidase + IV infusion of normal saline and Group III: Received mixture of bupivacaine 0.5% (4.5 ml) + lidocaine 2% (4.5 ml) + normal saline (1 ml) +150 IU hyaluronidase + IV dexmedetomidine 1 μg/kg over 10 min; followed by 0.4 μg/kg/h IV infusion. We recorded onset, duration of block, Ramsay Sedation Score, intra-ocular pressure (IOP), hemodynamics, and adverse effects. Results: There was a significant decrease in the onset of action and increase in the duration of block in Group II as compared with the Group I and Group III. Mean Ramsay Sedation Score was higher in Group III. The IOP showed a significant decrease in Group II and Group III 10 min after injection (P < 0.01). Heart rate showed a significant decrease in Group III in comparison with the two other groups (P < 0.05). Only two patients in Group III developed bradycardia. Conclusion: Dexmedetomidine as an additive shortens onset time, prolong block durations and significantly decreases the IOP with minimal side effects. IV dexmedetomidine, in addition, produces intra-operative sedation with hemodynamic stability. PMID:26952175

  6. Teaching the Comparative Approach to American Studies.

    ERIC Educational Resources Information Center

    Seaberg, Stanley

    The rationale behind this book of five suggested or sample comparative units contains several elements: 1) an interdisciplinary social science approach to studying the American past, present, and future; and 2) a view of our country's history in terms of a world setting and in the light on contemporary concerns. The global comparative method…

  7. Comparative Environmental Threat Analysis: Three Case Studies.

    ERIC Educational Resources Information Center

    Latour, J. B.; Reiling, R.

    1994-01-01

    Reviews how carrying capacity for different environmental problems is operationalized. Discusses whether it is possible to compare threats, using the exceeding of carrying capacity as a yardstick. Points out problems in comparative threat analysis using three case studies: threats to European groundwater resources, threats to ecosystems in Europe,…

  8. Effectiveness of additional supervised exercises compared with conventional treatment alone in patients with acute lateral ankle sprains: systematic review

    PubMed Central

    van Ochten, John; Luijsterburg, Pim A J; van Middelkoop, Marienke; Koes, Bart W; Bierma-Zeinstra, Sita M A

    2010-01-01

    Objective To summarise the effectiveness of adding supervised exercises to conventional treatment compared with conventional treatment alone in patients with acute lateral ankle sprains. Design Systematic review. Data sources Medline, Embase, Cochrane Central Register of Controlled Trials, Cinahl, and reference screening. Study selection Included studies were randomised controlled trials, quasi-randomised controlled trials, or clinical trials. Patients were adolescents or adults with an acute lateral ankle sprain. The treatment options were conventional treatment alone or conventional treatment combined with supervised exercises. Two reviewers independently assessed the risk of bias, and one reviewer extracted data. Because of clinical heterogeneity we analysed the data using a best evidence synthesis. Follow-up was classified as short term (up to two weeks), intermediate (two weeks to three months), and long term (more than three months). Results 11 studies were included. There was limited to moderate evidence to suggest that the addition of supervised exercises to conventional treatment leads to faster and better recovery and a faster return to sport at short term follow-up than conventional treatment alone. In specific populations (athletes, soldiers, and patients with severe injuries) this evidence was restricted to a faster return to work and sport only. There was no strong evidence of effectiveness for any of the outcome measures. Most of the included studies had a high risk of bias, with few having adequate statistical power to detect clinically relevant differences. Conclusion Additional supervised exercises compared with conventional treatment alone have some benefit for recovery and return to sport in patients with ankle sprain, though the evidence is limited or moderate and many studies are subject to bias. PMID:20978065

  9. Electrostatic Levitation for Studies of Additive Manufactured Materials

    NASA Technical Reports Server (NTRS)

    SanSoucie, Michael P.; Rogers, Jan R.; Tramel, Terri

    2014-01-01

    The electrostatic levitation (ESL) laboratory at NASA's Marshall Space Flight Center is a unique facility for investigators studying high temperature materials. The laboratory boasts two levitators in which samples can be levitated, heated, melted, undercooled, and resolidified. Electrostatic levitation minimizes gravitational effects and allows materials to be studied without contact with a container or instrumentation. The lab also has a high temperature emissivity measurement system, which provides normal spectral and normal total emissivity measurements at use temperature. The ESL lab has been instrumental in many pioneering materials investigations of thermophysical properties, e.g., creep measurements, solidification, triggered nucleation, and emissivity at high temperatures. Research in the ESL lab has already led to the development of advanced high temperature materials for aerospace applications, coatings for rocket nozzles, improved medical and industrial optics, metallic glasses, ablatives for reentry vehicles, and materials with memory. Modeling of additive manufacturing materials processing is necessary for the study of their resulting materials properties. In addition, the modeling of the selective laser melting processes and its materials property predictions are also underway. Unfortunately, there is very little data for the properties of these materials, especially of the materials in the liquid state. Some method to measure thermophysical properties of additive manufacturing materials is necessary. The ESL lab is ideal for these studies. The lab can provide surface tension and viscosity of molten materials, density measurements, emissivity measurements, and even creep strength measurements. The ESL lab can also determine melting temperature, surface temperatures, and phase transition temperatures of additive manufactured materials. This presentation will provide background on the ESL lab and its capabilities, provide an approach to using the ESL

  10. Comparative studies of gene regulatory mechanisms.

    PubMed

    Pai, Athma A; Gilad, Yoav

    2014-12-01

    It has become increasingly clear that changes in gene regulation have played an important role in adaptive evolution both between and within species. Over the past five years, comparative studies have moved beyond simple characterizations of differences in gene expression levels within and between species to studying variation in regulatory mechanisms. We still know relatively little about the precise chain of events that lead to most regulatory adaptations, but we have taken significant steps towards understanding the relative importance of changes in different mechanisms of gene regulatory evolution. In this review, we first discuss insights from comparative studies in model organisms, where the available experimental toolkit is extensive. We then focus on a few recent comparative studies in primates, where the limited feasibility of experimental manipulation dictates the approaches that can be used to study gene regulatory evolution. PMID:25215415

  11. BIG FROG WILDERNESS STUDY AREA AND ADDITIONS, TENNESSEE AND GEORGIA.

    USGS Publications Warehouse

    Slack, John F.; Gazdik, Gertrude C.

    1984-01-01

    A mineral-resource survey was made of the Big Frog Wilderness Study Area and additions, Tennessee-Georgia. Geochemical sampling found traces of gold, zinc, copper, and arsenic in rocks, stream sediments, and panned concentrates, but not in sufficient quantities to indicate the presence of deposits of these metals. The results of the survey indicate that there is little promise for the occurrence of metallic mineral deposits within the study area. The only apparent resources are nonmetallic commodities including rock suitable for construction materials, and small amounts of sand and gravel; however, these commodities are found in abundance outside the study area. A potential may exist for oil and natural gas at great depths, but this cannot be evaluated by the present study.

  12. Recommended Protocol for Round Robin Studies in Additive Manufacturing

    PubMed Central

    Moylan, Shawn; Brown, Christopher U.; Slotwinski, John

    2016-01-01

    One way to improve confidence and encourage proliferation of additive manufacturing (AM) technologies and parts is by generating more high quality data describing the performance of AM processes and parts. Many in the AM community see round robin studies as a way to generate large data sets while distributing the cost among the participants, thereby reducing the cost to individual users. The National Institute of Standards and Technology (NIST) has conducted and participated in several of these AM round robin studies. While the results of these studies are interesting and informative, many of the lessons learned in conducting these studies concern the logistics and methods of the study and unique issues presented by AM. Existing standards for conducting interlaboratory studies of measurement methods, along with NIST’s experience, form the basis for recommended protocols for conducting AM round robin studies. The role of round robin studies in AM qualification, some of the limitations of round robin studies, and the potential benefit of less formal collaborative experiments where multiple factors, AM machine being only one, are varied simultaneously are also discussed. PMID:27274602

  13. Genotoxicity studies of the food additive ester gum.

    PubMed

    Mukherjee, A; Agarwal, K; Chakrabarti, J

    1992-07-01

    Ester gum (EG) is used in citrus oil-based beverage flavourings as a weighting or colouring agent. In the present study, concentrations of 50, 100 and 150 mg/kg body weight were administered orally to male Swiss albino mice, and sister chromatid exchange and chromosomal aberration were used as the cytogenetic endpoints to determine the genotoxic and clastogenic potential of the food additive. Although EG was weakly clastogenic and could induce a marginal increase in sister chromatid exchange frequencies, it was not a potential health hazard at the doses tested. PMID:1521837

  14. Comparative mirror cleaning study: a study on removing particulate contamination

    NASA Astrophysics Data System (ADS)

    Houston, Karrie D.

    2006-08-01

    A mirror cleaning study was conducted to assess the effectiveness of three cleaning methods in their ability to remove particulate contamination from reflective mirror surfaces. Presently, the detergent bath, solvent rinse, and CO II snow cleaning methods are the most commonly used optical cleaning techniques within the optics industry. These techniques are also commonly used by the Optics Branch/Code 551 at Goddard Space Flight Center (GSFC) to remove particulate contamination from optical surfaces. In this experimental study, the above-mentioned cleaning methods were used to clean twelve uncoated silicon wafers, twelve gold coated silicon wafers, and twelve gold coated silicon wafers with a silicon oxide protective coating. CO II snow cleaning had an average removal percentage of 84%, followed by the solvent rinse at 74%, and the detergent bath at 61%. In addition to the average removal percentage, this comparative study was designed to: (1) determine the cleaning ability of each method based on the number and size of removed particles; (2) assess the risk of surface damage for each cleaning procedure; (3) evaluate each cleaning method as a function of its initial "qualitative" contamination level ("fairly clean", "dirty", and "very dirty"). The particulate cleanliness of all wafers was characterized using Image Analysis and Image-Pro Plus 5.0 software. In addition, the experimental design and experimental results were analyzed using JMP/Statistical Analytical Software Version 6.0.

  15. Additive toxicity of herbicide mixtures and comparative sensitivity of tropical benthic microalgae.

    PubMed

    Magnusson, Marie; Heimann, Kirsten; Quayle, Pamela; Negri, Andrew P

    2010-11-01

    Natural waters often contain complex mixtures of unknown contaminants potentially posing a threat to marine communities through chemical interactions. Here, acute effects of the photosystem II-inhibiting herbicides diuron, tebuthiuron, atrazine, simazine, and hexazinone, herbicide breakdown products (desethyl-atrazine (DEA) and 3,4-dichloroaniline (3,4-DCA)) and binary mixtures, were investigated using three tropical benthic microalgae; Navicula sp. and Cylindrotheca closterium (Ochrophyta) and Nephroselmis pyriformis (Chlorophyta), and one standard test species, Phaeodactylum tricornutum (Ochrophyta), in a high-throughput Maxi-Imaging-PAM bioassay (Maxi-IPAM). The order of toxicity was; diuron > hexazinone > tebuthiuron > atrazine > simazine > DEA > 3,4-DCA for all species. The tropical green alga N. pyriformis was up to 10-fold more sensitive than the diatoms tested here and reported for coral symbionts, and is recommended as a standard tropical test species for future research. All binary mixtures exhibited additive toxicity, and the use of herbicide equivalents (HEq) is therefore recommended in order to incorporate total-maximum-load measures for environmental regulatory purposes. PMID:20800855

  16. Making intelligent systems team players: Additional case studies

    NASA Technical Reports Server (NTRS)

    Malin, Jane T.; Schreckenghost, Debra L.; Rhoads, Ron W.

    1993-01-01

    Observations from a case study of intelligent systems are reported as part of a multi-year interdisciplinary effort to provide guidance and assistance for designers of intelligent systems and their user interfaces. A series of studies were conducted to investigate issues in designing intelligent fault management systems in aerospace applications for effective human-computer interaction. The results of the initial study are documented in two NASA technical memoranda: TM 104738 Making Intelligent Systems Team Players: Case Studies and Design Issues, Volumes 1 and 2; and TM 104751, Making Intelligent Systems Team Players: Overview for Designers. The objective of this additional study was to broaden the investigation of human-computer interaction design issues beyond the focus on monitoring and fault detection in the initial study. The results of this second study are documented which is intended as a supplement to the original design guidance documents. These results should be of interest to designers of intelligent systems for use in real-time operations, and to researchers in the areas of human-computer interaction and artificial intelligence.

  17. RAMSEYS DRAFT WILDERNESS STUDY AREA AND ADDITION, VIRGINIA.

    USGS Publications Warehouse

    Lesure, Frank G.; Mory, Peter C.

    1984-01-01

    Mineral-resource surveys of the Ramseys Draft Wilderness Study Area and adjoining roadless area addition in George Washington National Forest in the western valley and ridge province, Augusta and Highland Counties, Virginia, were done. The surveys outlined three small areas containing anomalous amounts of copper, lead, and zinc related to stratabound red-bed copper mineralization, but these occurrences are not large and are not considered as having mineral-resource potential. The area contains abundant sandstone suitable for construction materials and shale suitable for making brick, tile, and other low-grade ceramic products, but these commodities occur in abundance outside the wilderness study area. Structural conditions are probably favorable for the accumulation of natural gas, but exploratory drilling has not been done sufficiently near the area to evaluate the gas potential.

  18. Species comparative studies and cognitive development.

    PubMed

    Gómez, Juan-Carlos

    2005-03-01

    The comparative study of infant development and animal cognition brings to cognitive science the promise of insights into the nature and origins of cognitive skills. In this article, I review a recent wave of comparative studies conducted with similar methodologies and similar theoretical frameworks on how two core components of human cognition--object permanence and gaze following--develop in different species. These comparative findings call for an integration of current competing accounts of developmental change. They further suggest that evolution has produced developmental devices capable at the same time of preserving core adaptive components, and opening themselves up to further adaptive change, not only in interaction with the external environment, but also in interaction with other co-developing cognitive systems. PMID:15737820

  19. Ultrafine particle concentrations in the surroundings of an urban area: comparing downwind to upwind conditions using Generalized Additive Models (GAMs).

    PubMed

    Sartini, Claudio; Zauli Sajani, Stefano; Ricciardelli, Isabella; Delgado-Saborit, Juana Mari; Scotto, Fabiana; Trentini, Arianna; Ferrari, Silvia; Poluzzi, Vanes

    2013-10-01

    The aim of this study was to investigate the influence of an urban area on ultrafine particle (UFP) concentration in nearby surrounding areas. We assessed how downwind and upwind conditions affect the UFP concentration at a site placed a few kilometres from the city border. Secondarily, we investigated the relationship among other meteorological factors, temporal variables and UFP. Data were collected for 44 days during 2008 and 2009 at a rural site placed about 3 kilometres from Bologna, in northern Italy. Measurements were performed using a spectrometer (FMPS TSI 3091). The average UFP number concentration was 11 776 (±7836) particles per cm(3). We analysed the effect of wind direction in a multivariate Generalized Additive Model (GAM) adjusted for the principal meteorological parameters and temporal trends. An increase of about 25% in UFP levels was observed when the site was downwind of the urban area, compared with the levels observed when wind blew from rural areas. The size distribution of particles was also affected by the wind direction, showing higher concentration of small size particles when the wind blew from the urban area. The GAM showed a good fit to the data (R(2) = 0.81). Model choice was via Akaike Information Criteria (AIC). The analysis also revealed that an approach based on meteorological data plus temporal trends improved the goodness of the fit of the model. In addition, the findings contribute to evidence on effects of exposure to ultrafine particles on a population living in city surroundings. PMID:24077061

  20. A Comparative Study of Sparse Associative Memories

    NASA Astrophysics Data System (ADS)

    Gripon, Vincent; Heusel, Judith; Löwe, Matthias; Vermet, Franck

    2016-05-01

    We study various models of associative memories with sparse information, i.e. a pattern to be stored is a random string of 0s and 1s with about log N 1s, only. We compare different synaptic weights, architectures and retrieval mechanisms to shed light on the influence of the various parameters on the storage capacity.

  1. The Student Teaching Experience: A Comparative Study.

    ERIC Educational Resources Information Center

    Butler, Judy D.

    This paper describes a 1996 study that compared the student teaching experiences of a traditional and a nontraditional student to ascertain what differences in their experiences might imply about teacher preparation. The two students kept journals that could be written in at any time of the day. They recorded their impressions of their situation…

  2. A Comparative Study of Sparse Associative Memories

    NASA Astrophysics Data System (ADS)

    Gripon, Vincent; Heusel, Judith; Löwe, Matthias; Vermet, Franck

    2016-07-01

    We study various models of associative memories with sparse information, i.e. a pattern to be stored is a random string of 0s and 1s with about log N 1s, only. We compare different synaptic weights, architectures and retrieval mechanisms to shed light on the influence of the various parameters on the storage capacity.

  3. RNAseq by Total RNA Library Identifies Additional RNAs Compared to Poly(A) RNA Library

    PubMed Central

    Guo, Yan; Zhao, Shilin; Sheng, Quanhu; Guo, Mingsheng; Lehmann, Brian; Pietenpol, Jennifer; Samuels, David C.; Shyr, Yu

    2015-01-01

    The most popular RNA library used for RNA sequencing is the poly(A) captured RNA library. This library captures RNA based on the presence of poly(A) tails at the 3′ end. Another type of RNA library for RNA sequencing is the total RNA library which differs from the poly(A) library by capture method and price. The total RNA library costs more and its capture of RNA is not dependent on the presence of poly(A) tails. In practice, only ribosomal RNAs and small RNAs are washed out in the total RNA library preparation. To evaluate the ability of detecting RNA for both RNA libraries we designed a study using RNA sequencing data of the same two breast cancer cell lines from both RNA libraries. We found that the RNA expression values captured by both RNA libraries were highly correlated. However, the number of RNAs captured was significantly higher for the total RNA library. Furthermore, we identify several subsets of protein coding RNAs that were not captured efficiently by the poly(A) library. One of the most noticeable is the histone-encode genes, which lack the poly(A) tail. PMID:26543871

  4. Comparing the performance of geostatistical models with additional information from covariates for sewage plume characterization.

    PubMed

    Del Monego, Maurici; Ribeiro, Paulo Justiniano; Ramos, Patrícia

    2015-04-01

    In this work, kriging with covariates is used to model and map the spatial distribution of salinity measurements gathered by an autonomous underwater vehicle in a sea outfall monitoring campaign aiming to distinguish the effluent plume from the receiving waters and characterize its spatial variability in the vicinity of the discharge. Four different geostatistical linear models for salinity were assumed, where the distance to diffuser, the west-east positioning, and the south-north positioning were used as covariates. Sample variograms were fitted by the Matèrn models using weighted least squares and maximum likelihood estimation methods as a way to detect eventual discrepancies. Typically, the maximum likelihood method estimated very low ranges which have limited the kriging process. So, at least for these data sets, weighted least squares showed to be the most appropriate estimation method for variogram fitting. The kriged maps show clearly the spatial variation of salinity, and it is possible to identify the effluent plume in the area studied. The results obtained show some guidelines for sewage monitoring if a geostatistical analysis of the data is in mind. It is important to treat properly the existence of anomalous values and to adopt a sampling strategy that includes transects parallel and perpendicular to the effluent dispersion. PMID:25345922

  5. Experimental Study of Additives on Viscosity biodiesel at Low Temperature

    NASA Astrophysics Data System (ADS)

    Fajar, Berkah; Sukarno

    2015-09-01

    An experimental investigation was performed to find out the viscosity of additive and biodiesel fuel mixture in the temperature range from 283 K to 318 K. Solutions to reduce the viscosity of biodiesel is to add the biodiesel with some additive. The viscosity was measured using a Brookfield Rheometer DV-II. The additives were the generic additive (Diethyl Ether/DDE) and the commercial additive Viscoplex 10-330 CFI. Each biodiesel blends had a concentration of the mixture: 0.0; 0.25; 0.5; 0.75; 1.0; and 1.25% vol. Temperature of biodiesel was controlled from 40°C to 0°C. The viscosity of biodiesel and additive mixture at a constant temperature can be approximated by a polynomial equation and at a constant concentration by exponential equation. The optimum mixture is at 0.75% for diethyl ether and 0.5% for viscoplex.

  6. Evaluating synteny for improved comparative studies

    PubMed Central

    Ghiurcuta, Cristina G.; Moret, Bernard M. E.

    2014-01-01

    Motivation: Comparative genomics aims to understand the structure and function of genomes by translating knowledge gained about some genomes to the object of study. Early approaches used pairwise comparisons, but today researchers are attempting to leverage the larger potential of multi-way comparisons. Comparative genomics relies on the structuring of genomes into syntenic blocks: blocks of sequence that exhibit conserved features across the genomes. Syntenic blocs are required for complex computations to scale to the billions of nucleotides present in many genomes; they enable comparisons across broad ranges of genomes because they filter out much of the individual variability; they highlight candidate regions for in-depth studies; and they facilitate whole-genome comparisons through visualization tools. However, the concept of syntenic block remains loosely defined. Tools for the identification of syntenic blocks yield quite different results, thereby preventing a systematic assessment of the next steps in an analysis. Current tools do not include measurable quality objectives and thus cannot be benchmarked against themselves. Comparisons among tools have also been neglected—what few results are given use superficial measures unrelated to quality or consistency. Results: We present a theoretical model as well as an experimental basis for comparing syntenic blocks and thus also for improving or designing tools for the identification of syntenic blocks. We illustrate the application of the model and the measures by applying them to syntenic blocks produced by three different contemporary tools (DRIMM-Synteny, i-ADHoRe and Cyntenator) on a dataset of eight yeast genomes. Our findings highlight the need for a well founded, systematic approach to the decomposition of genomes into syntenic blocks. Our experiments demonstrate widely divergent results among these tools, throwing into question the robustness of the basic approach in comparative genomics. We have taken

  7. Doxofylline and Theophylline: A Comparative Clinical Study

    PubMed Central

    Akram, MD Faiz; Nasiruddin, Mohammad; Ahmad, Zuber; Ali Khan, Rahat

    2012-01-01

    Objectives COPD is one of the major public health problems worldwide. Theophylline has been used in the treatment of COPD for decades. Doxofylline a new theophylline congener has been claimed to have better safety profile. The study was undertaken to compare theophylline and doxophylline at doses recommended and commonly used in clinical practice. Methods The study was conducted in patients of COPD in TB chest department of a medical college hospital. It was randomized, prospective and open label. A total of 154 patients were divided in two group .Group I was administered 400 mg theophylline SR once daily and group II was administered doxofylline 400 mg twice a day orally. Spirometric variables symptom score, and adverse effects were recorded on day 0, 7 and 21 of therapy. Data were compared and analysed using SPSS version 16. Results Results of the study showed that there was no statistically significant difference with respect to spirometric variables and symptom score in the two groups and there was no significant difference in two groups with respect to side effects (p>0.05). Conclusions It is concluded that doxophylline has no advantage over theophylline in terms of either efficacy or safety on the doses commonly used in current clinical practice. PMID:23373027

  8. Comparative study of INPIStron and spark gap

    NASA Technical Reports Server (NTRS)

    Han, Kwang S.; Lee, Ja H.

    1993-01-01

    An inverse pinch plasma switch, INPIStron, was studied in comparison to a conventional spark gap. The INPIStron is under development for high power switching applications. The INPIStron has an inverse pinch dynamics, opposed to Z-pinch dynamics in the spark gap. The electrical, plasma dynamics and radiative properties of the closing plasmas have been studied. Recently the high-voltage pulse transfer capabilities or both the INPIStron and the spark gap were also compared. The INPIStron with a low impedance Z = 9 ohms transfers 87 percent of an input pulse with a halfwidth of 2 mu s. For the same input pulse the spark gap of Z = 100 ohms transfers 68 percent. Fast framing and streak photography, taken with an TRW image converter camera, was used to observe the discharge uniformity and closing plasma speed in both switches. In order to assess the effects of closing plasmas on erosion of electrode material, emission spectra of two switches were studied with a spectrometer-optical multi channel analyzer (OMA) system. The typical emission spectra of the closing plasmas in the INPIStron and the spark gap showed that there were comparatively weak carbon line emission in 658.7 nm and copper (electrode material) line emissions in the INPIStron, indicating low erosion of materials in the INPIStron.

  9. EFQPSK Versus CERN: A Comparative Study

    NASA Technical Reports Server (NTRS)

    Borah, Deva K.; Horan, Stephen

    2001-01-01

    This report presents a comparative study on Enhanced Feher's Quadrature Phase Shift Keying (EFQPSK) and Constrained Envelope Root Nyquist (CERN) techniques. These two techniques have been developed in recent times to provide high spectral and power efficiencies under nonlinear amplifier environment. The purpose of this study is to gain insights into these techniques and to help system planners and designers with an appropriate set of guidelines for using these techniques. The comparative study presented in this report relies on effective simulation models and procedures. Therefore, a significant part of this report is devoted to understanding the mathematical and simulation models of the techniques and their set-up procedures. In particular, mathematical models of EFQPSK and CERN, effects of the sampling rate in discrete time signal representation, and modeling of nonlinear amplifiers and predistorters have been considered in detail. The results of this study show that both EFQPSK and CERN signals provide spectrally efficient communications compared to filtered conventional linear modulation techniques when a nonlinear power amplifier is used. However, there are important differences. The spectral efficiency of CERN signals, with a small amount of input backoff, is significantly better than that of EFQPSK signals if the nonlinear amplifier is an ideal clipper. However, to achieve such spectral efficiencies with a practical nonlinear amplifier, CERN processing requires a predistorter which effectively translates the amplifier's characteristics close to those of an ideal clipper. Thus, the spectral performance of CERN signals strongly depends on the predistorter. EFQPSK signals, on the other hand, do not need such predistorters since their spectra are almost unaffected by the nonlinear amplifier, Ibis report discusses several receiver structures for EFQPSK signals. It is observed that optimal receiver structures can be realized for both coded and uncoded EFQPSK

  10. Comparative Study of Vented vs. Unvented Crawlspaces

    SciTech Connect

    Biswas, Kaushik; Christian, Jeffrey E; Gehl, Anthony C

    2011-10-01

    There has been a significant amount of research in the area of building energy efficiency and durability. However, well-documented quantitative information on the impact of crawlspaces on the performance of residential structures is lacking. The objective of this study was to evaluate and compare the effects of two crawlspace strategies on the whole-house performance of a pair of houses in a mixed humid climate. These houses were built with advanced envelope systems to provide energy savings of 50% or more compared to traditional 2010 new construction. One crawlspace contains insulated walls and is sealed and semi-conditioned. The other is a traditional vented crawlspace with insulation in the crawlspace ceiling. The vented (traditional) crawlspace contains fiberglass batts installed in the floor chase cavities above the crawl, while the sealed and insulated crawlspace contains foil-faced polyisocyanurate foam insulation on the interior side of the masonry walls. Various sensors to measure temperatures, heat flux through crawlspace walls and ceiling, and relative humidity were installed in the two crawlspaces. Data from these sensors have been analyzed to compare the performance of the two crawlspace designs. The analysis results indicated that the sealed and insulated crawlspace design is better than the traditional vented crawlspace in the mixed humid climate.

  11. A comparative study between shielded and open coplanar waveguide discontinuities

    NASA Technical Reports Server (NTRS)

    Dib, Nihad I.; Harokopus, W. P., Jr.; Ponchak, G. E.; Katehi, L. P. B.

    1993-01-01

    A comparative study between open and shielded coplanar waveguide (CPW) discontinuities is presented. The space domain integral equation method is used to characterize several discontinuities such as the open-end CPW and CPW series stubs. Two different geometries of CPW series stubs (straight and bent stubs) are compared with respect to resonant frequency and radiation loss. In addition, the encountered radiation loss due to different CPW shunt stubs is evaluated experimentally. The notion of forced radiation simulation is presented, and the results of such a simulation are compared to the actual radiation loss obtained rigorously. It is shown that such a simulation cannot give reliable results concerning radiation loss from printed circuits.

  12. Pairing Fluctuations Above Tc: A Comparative Study

    NASA Astrophysics Data System (ADS)

    Verga, Simona; Gooding, Robert J.; Marsiglio, Frank

    2003-03-01

    Although the investigation of superconductivity in High Tc Cuprates has been extensive, its microscopic origin is still under debate. An important experimental fact is the universality of many properties of the cuprates (the low dimensionality, the d-wave symmetry of the superconducting gap and the pseudogap), which must be reproduced by any competitive theory. While there is no consensus about the 'glue' that binds two electrons in a pair, one can gain insight by simply providing it, without questioning its nature. The Attractive Hubbard Model for electrons on a lattice provides the means for such an approach, but even if it simplifies the picture considerably, in the coupling regime of interest one needs to rely on approximate theories. We present a comparative study of different versions of the T-matrix approximation in the atomic limit (strong coupling), where the existence of analytical solutions enables us to test how well the approximations work. We also employ a non-perturbative approach due to Y. M. Vilk and A.-M. S. Tremblay and compare it with the T-matrix and the analytical solutions. We discuss the relevance of such a study for other coupling regimes and more realistic models.

  13. Generating Scenarios of Addition and Subtraction: A Study of Japanese University Students

    ERIC Educational Resources Information Center

    Kinda, Shigehiro

    2013-01-01

    Students are presented with problems involving three scenario types of addition and subtraction in elementary mathematics: one dynamic ("Change") and two static ("Combine, Compare"). Previous studies have indicated that the dynamic type is easier for school children, whereas the static types are more difficult and comprehended only gradually…

  14. Health studies indicate MTBE is safe gasoline additive

    SciTech Connect

    Anderson, E.V.

    1993-09-01

    Implementation of the oxygenated fuels program by EPA in 39 metropolitan areas, including Fairbanks and Anchorage, Alaska, in the winter of 1992, encountered some unexpected difficulties. Complaints of headaches, dizziness, nausea, and irritated eyes started in Fairbanks, jumped to Anchorage, and popped up in various locations in the lower 48 states. The suspected culprit behind these complaints was the main additive for oxygenation of gasoline is methyl tert-butyl ether (MTBE). A test program, hastily organized in response to these complaints, has indicated that MTBE is a safe gasoline additive. However, official certification of the safety of MTBE is still awaited.

  15. COMPARATIVE STUDIES OF HERPETOMONADS AND LEISHMANIAS

    PubMed Central

    Noguchi, Hideyo; Tilden, Evelyn B.

    1926-01-01

    Nine strains of herpetomonads have been isolated in pure culture from eight varieties of insects, and three strains from two species of plants. Four of the cultures were derived from latex-feeding insects (Oncopeltus fasciatus, Oncopeltus sp. ?, Lygæus kalmii) and three from latex plants (Asclepias syriaca, Asclepias nivea), two from mosquitoes (Culex pipiens and Anopheles quadrimaculatus), one from the house fly (Musca domestica), and two from bluebottle flies. In addition impure cultures have been obtained from Oncopeltus cingulifer and from its plant host, Asclepias curassavica. The flagellates cultivated, all of which belong to the genus Herpetomonas, have been identified chiefly by their biological relationships, which will be described in detail in Part II of this report. The seven strains from latex-feeding insects and latex plants represent two distinct species, which have been designated H. oncopelti and H. lygægorum. The two strains from mosquitoes proved to be the same organism and have been called Herpetomonas culicidarum. The culture obtained from Musca domestica contained larger individuals than those of any other strain, and the organism is morphologically distinct from either of the Calliphora strains. None of the fly flagellates cultivated could be identified with the. species H. muscæ domesticæ or H. calliphoræ, and hence they have been given new names, Herpetomonas muscidarum, H. media, and H. parva. Blood agar plates were used for initial cultivation of the strains from insects and the semisolid leptospira medium for isolation of the plant flagellates. A number of the strains were purified by plating on acid blood agar, a procedure which reduces considerably the growth of bacterial contaminants. The Barber technique was utilized for isolation of the flagellates from flies, because of the very large number of bacteria found with them in these insects, and, in one or two instances, for the purification of impure cultures. Once they have been

  16. Scatterometry or imaging overlay: a comparative study

    NASA Astrophysics Data System (ADS)

    Hsu, Simon C. C.; Pai, Yuan Chi; Chen, Charlie; Yu, Chun Chi; Hsing, Henry; Wu, Hsing-Chien; Kuo, Kelly T. L.; Amir, Nuriel

    2015-03-01

    Most fabrication facilities today use imaging overlay measurement methods, as it has been the industry's reliable workhorse for decades. In the last few years, third-generation Scatterometry Overlay (SCOL™) or Diffraction Based Overlay (DBO-1) technology was developed, along another DBO technology (DBO-2). This development led to the question of where the DBO technology should be implemented for overlay measurements. Scatterometry has been adopted for high volume production in only few cases, always with imaging as a backup, but scatterometry overlay is considered by many as the technology of the future. In this paper we compare imaging overlay and DBO technologies by means of measurements and simulations. We outline issues and sensitivities for both technologies, providing guidelines for the best implementation of each. For several of the presented cases, data from two different DBO technologies are compared as well, the first with Pupil data access (DBO-1) and the other without pupil data access (DBO-2). Key indicators of overlay measurement quality include: layer coverage, accuracy, TMU, process robustness and robustness to process changes. Measurement data from real cases across the industry are compared and the conclusions are also backed by simulations. Accuracy is benchmarked with reference OVL, and self-consistency, showing good results for Imaging and DBO-1 technology. Process sensitivity and metrology robustness are mostly simulated with MTD (Metrology Target Designer) comparing the same process variations for both technologies. The experimental data presented in this study was done on ten advanced node layers and three production node layers, for all phases of the IC fabrication process (FEOL, MEOL and BEOL). The metrology tool used for most of the study is KLA-Tencor's Archer 500LCM system (scatterometry-based and imaging-based measurement technologies on the same tool) another type of tool is used for DBO-2 measurements. Finally, we conclude that

  17. A comparative study on monitored anesthesia care

    PubMed Central

    Sen, Jayashree; Sen, Bitan

    2014-01-01

    Aim: The aim of this study is to compare the effectiveness, hemodynamic changes and duration of sedation and analgesia between combinations of fortwin-phenergan-midazolam (FPM) and ketamine - midazolam (KM) along with local anesthesia for the surgeries done under the umbrella of monitored anesthesia care. Materials and Methods: A total of 50 patients undergoing surgeries as tympanoplasty, septoplasty, lip repair, dacrocystectomy and cataract under local anesthesia, randomly received either intravenous (IV) fortwin 0.3 mg/kg over 1 min followed by IV midazolam 0.04 mg/kg plus IV phenergan 12.5 mg (Group FPM) or IV ketamine 0.3 mg/kg over 1 min plus IV midazolam 0.04 mg/kg (Group KM). Sedation was titrated to Ramsay sedation score (RSS) of 3. Patients’ mean arterial pressure (MAP), heart rate (HR), saturation peripheral pulse, duration of sedation and need for intraoperative rescue sedation/analgesic were recorded and compared. Satisfaction of patients (using a 1-7 point Likert verbal rating scale) and readiness for discharge towards (time to Aldrete score of 10) were also determined. Result: Group KM had significant rise in HR (20-25%) and MAP (25-30%) from 30 min after the bolus dose given until the end of the surgery in contrast to Group FPM. The target sedation level (RSS ≥ 3) was higher in Group FPM (n = 23 [92%]) as compared with Group KM (n = 12 [48%]). Time until need for rescue sedation was 66.96 ± 17.19 min in FPM and 32.80 ± 8.90 min in KM group. The patient satisfaction (Likert scale) is more with the FPM group (6.12 ± 0.83 vs. 4.40 ± 1.20). Conclusion: We found that the combination of FPM is superior to the KM combination as per the hemodynamic changes, duration of analgesia, patients’ satisfaction and efficacy of the drugs are concerned. PMID:25886327

  18. Comparative Study of Airfoil Flow Separation Criteria

    NASA Astrophysics Data System (ADS)

    Laws, Nick; Kahouli, Waad; Epps, Brenden

    2015-11-01

    Airfoil flow separation impacts a multitude of applications including turbomachinery, wind turbines, and bio-inspired micro-aerial vehicles. In order to achieve maximum performance, some devices operate near the edge of flow separation, and others use dynamic flow separation advantageously. Numerous criteria exist for predicting the onset of airfoil flow separation. This talk presents a comparative study of a number of such criteria, with emphasis paid to speed and accuracy of the calculations. We evaluate the criteria using a two-dimensional unsteady vortex lattice method, which allows for rapid analysis (on the order of seconds instead of days for a full Navier-Stokes solution) and design of optimal airfoil geometry and kinematics. Furthermore, dynamic analyses permit evaluation of dynamic stall conditions for enhanced lift via leading edge vortex shedding, commonly present in small flapping-wing flyers such as the bumblebee and hummingbird.

  19. Comparative microscopy study of Vibrio cholerae flagella

    NASA Astrophysics Data System (ADS)

    Konnov, Nikolai P.; Baiburin, Vil B.; Zadnova, Svetlana P.; Volkov, Uryi P.

    1999-06-01

    A fine structure of bacteria flagella is an important problem of molecular cell biology. Bacteria flagella are the self-assembled structures that allow to use the flagellum protein in a number of biotechnological applications. However, at present, there is a little information about high resolution scanning probe microscopy study of flagellum structure, in particular, about investigation of Vibrio cholerae flagella. In our lab have been carried out the high resolution comparative investigation of V. cholerae flagella by means of various microscopes: tunneling (STM), scanning force (SFM) and electron transmission. As a scanning probe microscope is used designed in our lab versatile SPM with replaceable measuring heads. Bacteria were grown, fixed and treated according to the conventional techniques. For STM investigations samples were covered with Pt/Ir thin films by rotated vacuum evaporation, in SFM investigations were used uncovered samples. Electron microscopy of the negatively stained bacteria was used as a test procedure.

  20. Supracostal percutaneous nephrolithotomy: A prospective comparative study

    PubMed Central

    Sinha, Maneesh; Krishnappa, Pramod; Subudhi, Santosh Kumar; Krishnamoorthy, Venkatesh

    2016-01-01

    Introduction: A widely prevalent fear of thoracic complications with the supracostal approach has led to its underutilization in percutaneous nephrolithotomy (PCNL). We frequently use the supracostal approach and compared the efficacy and thoracic complications of infracostal, supra 12th, and supra 11th punctures. Materials and Methods: This was a prospective study of patients who underwent PCNL between January 2005 and December 2012. The patients were divided into three groups based on the access: infracostal, supra 12th (between the 11th and 12th ribs) and supra 11th (between the 10th and 11th ribs). Clearance rates, fall in hemoglobin levels, transfusion rates, perioperative analgesic requirements, hospital stay and thoracic complications were compared. Results: Seven hundred patients were included for analysis. There were 179 (25.5%) patients in the supra 11th group, 187 (26.7%) patients in the supra 12th group and 334 (47.8%) patients in the infracostal group. The overall clearance rate was 78% with no difference in the three groups. The postoperative analgesic requirements were significantly higher in the supracostal groups and showed a graded increase from infracostal to supra 12th to supra 11th. During the study period, only 2 patients required angioembolization (0.3%) and none required open exploration. The number of patients requiring intercostal chest drain insertion was extremely low, at 1.6% and 2.2% in the supra 12th and supra 11th groups, respectively. Conclusions: Our results confirm the feasibility of the supracostal approach including punctures above the 11th rib, albeit at the cost of an increase in thoracic complications. Staying in the line of the calyx has helped us to minimize the most dreaded complication of bleeding requiring angioembolization. PMID:26941494

  1. Comparative study of pressure-flow parameters.

    PubMed

    Eri, Lars M; Wessel, Nicolai; Tysland, Ole; Berge, Viktor

    2002-01-01

    Methods for quantification of bladder outlet obstruction (BOO) are still controversial. Parameters such as detrusor opening pressure (p(det.open)), maximum detrusor pressure (p(det.max)), minimum voiding pressure (p(det.min.void)), and detrusor pressure at maximum flow rate (P(det.Qmax)) separate obstructed from nonobstructed patients to some extent, but two nomograms, the Abrams-Griffiths nomogram and the linearized passive urethral resistance relation (LinPURR), are more accepted for this purpose, along with the urethral resistance algorithm. In this retrospective, methodologic study, we evaluated the properties of these parameters with regard to test-retest reproducibility and ability to detect a moderate (pharmacologic) and a pronounced (surgical) relief of bladder outlet obstruction. We studied the pressure-flow charts of 42 patients who underwent 24 weeks of androgen suppressive therapy, 42 corresponding patients who received placebo, and 30 patients who had prostate surgery. The patients performed repeat void pressure-flow examinations before and after treatment or placebo. The various parameters were compared. Among the bladder pressure parameters, P(det.Qmax) seemed to have some advantages, supporting the belief that it is the most relevant detrusor pressure parameter to include in nomograms to quantify BOO. In assessment of a large decrease in urethral resistance, such as after TURp, resistance parameters that are based on maximum flow rate as well as detrusor pressure are preferable. PMID:11948710

  2. A comparative study of depot injection techniques.

    PubMed

    Quartermaine, S; Taylor, R

    Depot injections of long-acting neuroleptic drugs, by maintaining a consistent drug regime, together with regular contact with health-care professionals, are an important factor in helping psychiatric patients who live in the community. As these injections are administered over a long period--often for years--it is important that care is taken to minimise discomfort and to reduce the incidence of problems at the injection site. Seepage of even small amounts of the medication will result in an inaccurate dose being absorbed and, owing to the irritant nature of many of these drugs, leakage into subcutaneous tissue and on to the skin surface can cause pain, irritation and lesions. This study was set up to compare two techniques of administering deep intramuscular injections to determine which best fulfilled the criteria of preventing seepage while causing as little discomfort as possible. The two methods used were the Z-track, which is standard practice in the UK, and the air bubble, which is widely taught and used in Canada and the USA. The study showed the air-bubble method to be significantly more effective at controlling seepage than the Z-track. PMID:7644369

  3. Egress of Alphaherpesviruses: Comparative Ultrastructural Study

    PubMed Central

    Granzow, Harald; Klupp, Barbara G.; Fuchs, Walter; Veits, Jutta; Osterrieder, Nikolaus; Mettenleiter, Thomas C.

    2001-01-01

    Egress of four important alphaherpesviruses, equine herpesvirus 1 (EHV-1), herpes simplex virus type 1 (HSV-1), infectious laryngotracheitis virus (ILTV), and pseudorabies virus (PrV), was investigated by electron microscopy of infected cell lines of different origins. In all virus-cell systems analyzed, similar observations were made concerning the different stages of virion morphogenesis. After intranuclear assembly, nucleocapsids bud at the inner leaflet of the nuclear membrane, resulting in enveloped particles in the perinuclear space that contain a sharply bordered rim of tegument and a smooth envelope surface. Egress from the perinuclear cisterna primarily occurs by fusion of the primary envelope with the outer leaflet of the nuclear membrane, which has been visualized for HSV-1 and EHV-1 for the first time. The resulting intracytoplasmic naked nucleocapsids are enveloped at membranes of the trans-Golgi network (TGN), as shown by immunogold labeling with a TGN-specific antiserum. Virions containing their final envelope differ in morphology from particles within the perinuclear cisterna by visible surface projections and a diffuse tegument. Particularly striking was the addition of a large amount of tegument material to ILTV capsids in the cytoplasm. Extracellular virions were morphologically identical to virions within Golgi-derived vesicles, but distinct from virions in the perinuclear space. Studies with gB- and gH-deleted PrV mutants indicated that these two glycoproteins, which are essential for virus entry and direct cell-to-cell spread, are dispensable for egress. Taken together, our studies indicate that the deenvelopment-reenvelopment process of herpesvirus maturation also occurs in EHV-1, HSV-1, and ILTV and that membrane fusion processes occurring during egress are substantially different from those during entry and direct viral cell-to-cell spread. PMID:11264357

  4. Enhanced L-lactic acid production in Lactobacillus paracasei by exogenous proline addition based on comparative metabolite profiling analysis.

    PubMed

    Tian, Xiwei; Wang, Yonghong; Chu, Ju; Zhuang, Yingping; Zhang, Siliang

    2016-03-01

    This study investigated cell physiological and metabolic responses of Lactobacillus paracasei to osmotic stresses. Both cellular fatty acid composition and metabolite profiling were responded by increasing unsaturated and epoxy-fatty acid proportions, as well as accumulating some specific intracellular metabolites. Simultaneously, metabolite profiling was adopted to rationally and systematically discover potential osmoprotectants. Consequently, exogenous addition of proline or aspartate was validated to be a feasible and efficacious approach to improve cell growth under hyperosmotic stress in shake flasks. Particularly, with 5-L cultivation system, L-lactic acid concentration increased from 108 to 150 g/L during the following 16-h fermentation in 2 g/L proline addition group, while it only increased from 110 to 140 g/L in no proline addition group. Moreover, glucose consumption rate with proline addition reached 3.49 g/L/h during this phase, 35.8 % higher than that with no proline addition. However, extreme high osmotic pressure would significantly limit the osmoprotection of proline, and the osmolality threshold for L. paracasei was approximately 3600 mOsm/kg. It was suggested that proline principally played a role as a compatible solute accumulated in the cell for hyperosmotic preservation. The strategies of exploiting osmotic protectant with metabolite profiling and enhancing L-lactic acid production by osmoprotectant addition would be potential to provide a new insight for other microorganisms and organic acids production. PMID:26658821

  5. Periodontal files--a comparative study.

    PubMed

    Pasquini, R; Clark, S M; Baradaran, S; Adams, D F

    1995-12-01

    Periodontal files are used by many dentists for instrumentation of root surfaces as a part of periodontal treatment. The purposes of this study were: 1) to examine, evaluate, and compare several periodontal files in 3 different conditions: new, used, and used/sharpened and 2) to evaluate the efficacy of 5 sharpening devices. The main characteristics observed included: the number, shape, and interval of blades; the active, rake, and lip angles; changes induced by wear; the influence of sharpening; and the type of metal surfaces comprising the blades. There was a wide range of active angles on each individual file, from a high of 75 degrees to a low of 51 degrees. The range of active angles for all blades on all new files was even greater, from a high of 87 degrees to a low of 30 degrees. Wear, observed on some but not all blades, was not extensive and appeared either as abrasion or, occasionally, as fracture of the blade edge. Sharpness scores (5 = sharpest and 1 = dullest) for new file blades were also extremely variable and spanned the full range of values, with a majority of blades scoring 3.5 and below. Attempts to sharpen files with several devices produced inconsistent results. All 5 sharpening devices had significant shortcomings. It was concluded that the extreme ranges both in active angles and in sharpness scores probably have a significant influence on effectiveness of root instrumentation. PMID:8683416

  6. Assays for mammalian tyrosinase: a comparative study

    SciTech Connect

    Jara, J.R.; Solano, F.; Lozano, J.A.

    1988-01-01

    This work describes a comparative study of the tyrosinase activity determined using three methods which are the most extensively employed; two radiometric assays using L-tyrosine as substrate (tyrosine hydroxylase and melanin formation activities) and one spectrophotometric assay using L-dopa (dopa oxidase activity). The three methods were simultaneously employed to measure the activities of the soluble, melanosomal, and microsomal tyrosinase isozymes from Harding-Passey mouse melanoma through their purification processes. The aim of this study was to find any correlation among the tyrosinase activities measured by the three different assays and to determine whether that correlation varied with the isozyme and its degree of purification. The results show that mammalian tyrosinase has a greater turnover number for L-dopa than for L-tyrosine. Thus, enzyme activity, expressed as mumol of substrate transformed per min, is higher in assays using L-dopa as substrate than those using L-tyrosine. Moreover, the percentage of hydroxylated L-tyrosine that is converted into melanin is low and is affected by several factors, apparently decreasing the tyrosinase activity measured by the melanin formation assay. Bearing these considerations in mind, average interassay factors are proposed. Their values are 10 to transform melanin formation into tyrosine hydroxylase activity, 100 to transform tyrosine hydroxylase into dopa oxidase activity, and 1,000 to transform melanin formation into dopa oxidase activity. Variations in these values due to the presence in the tyrosinase preparations of either inhibitors or regulatory factors in melanogenesis independent of tyrosinase are also discussed.

  7. Fitting additive hazards models for case-cohort studies: a multiple imputation approach.

    PubMed

    Jung, Jinhyouk; Harel, Ofer; Kang, Sangwook

    2016-07-30

    In this paper, we consider fitting semiparametric additive hazards models for case-cohort studies using a multiple imputation approach. In a case-cohort study, main exposure variables are measured only on some selected subjects, but other covariates are often available for the whole cohort. We consider this as a special case of a missing covariate by design. We propose to employ a popular incomplete data method, multiple imputation, for estimation of the regression parameters in additive hazards models. For imputation models, an imputation modeling procedure based on a rejection sampling is developed. A simple imputation modeling that can naturally be applied to a general missing-at-random situation is also considered and compared with the rejection sampling method via extensive simulation studies. In addition, a misspecification aspect in imputation modeling is investigated. The proposed procedures are illustrated using a cancer data example. Copyright © 2015 John Wiley & Sons, Ltd. PMID:26194861

  8. Additional Treatments Offer Little Benefit for Pancreatic Cancer: Study

    MedlinePlus

    ... of gastroenterology-pancreatology at Beaujon Hospital, in Clichy, France. The study was funded by the pharmaceutical company ... D., department of gastroenterology-pancreatology, Beaujon Hospital, Clichy, France; Deborah Schrag, M.D., M.P.H., chief ...

  9. NMR relaxometry study of plaster mortar with polymer additives

    SciTech Connect

    Jumate, E.; Manea, D.; Moldovan, D.; Fechete, R.

    2013-11-13

    The cement mixed with water forms a plastic paste or slurry which stiffness in time and finally hardens into a resistant stone. The addition of sand aggregates, polymers (Walocel) and/or calcium carbonate will modify dramatically the final mortar mechanic and thermal properties. The hydration processes can be observed using the 1D NMR measurements of transverse T{sub 2} relaxation times distributions analysed by a Laplace inversion algorithm. These distributions were obtained for mortar pasta measured at 2 hours after preparation then at 3, 7 and 28 days after preparation. Multiple components are identified in the T{sub 2} distributions. These can be associated with the proton bounded chemical or physical to the mortar minerals characterized by a short T{sub 2} relaxation time and to water protons in pores with three different pore sizes as observed from SEM images. The evaporation process is faster in the first hours after preparation, while the mortar hydration (bonding of water molecules to mortar minerals) can be still observed after days or months from preparation. Finally, the mechanic resistance was correlated with the transverse T{sub 2} relaxation rates corresponding to the bound water.

  10. Comparative Study of Two Automatic Registration Algorithms

    NASA Astrophysics Data System (ADS)

    Grant, D.; Bethel, J.; Crawford, M.

    2013-10-01

    The Iterative Closest Point (ICP) algorithm is prevalent for the automatic fine registration of overlapping pairs of terrestrial laser scanning (TLS) data. This method along with its vast number of variants, obtains the least squares parameters that are necessary to align the TLS data by minimizing some distance metric between the scans. The ICP algorithm uses a "model-data" concept in which the scans obtain differential treatment in the registration process depending on whether they were assigned to be the "model" or "data". For each of the "data" points, corresponding points from the "model" are sought. Another concept of "symmetric correspondence" was proposed in the Point-to-Plane (P2P) algorithm, where both scans are treated equally in the registration process. The P2P method establishes correspondences on both scans and minimizes the point-to-plane distances between the scans by simultaneously considering the stochastic properties of both scans. This paper studies both the ICP and P2P algorithms in terms of their consistency in registration parameters for pairs of TLS data. The question being investigated in this paper is, should scan A be registered to scan B, will the parameters be the same if scan B were registered to scan A? Experiments were conducted with eight pairs of real TLS data which were registered by the two algorithms in the forward (scan A to scan B) and backward (scan B to scan A) modes and the results were compared. The P2P algorithm was found to be more consistent than the ICP algorithm. The differences in registration accuracy between the forward and backward modes were negligible when using the P2P algorithm (mean difference of 0.03 mm). However, the ICP had a mean difference of 4.26 mm. Each scan was also transformed by the forward and backward parameters of the two algorithms and the misclosure computed. The mean misclosure for the P2P algorithm was 0.80 mm while that for the ICP algorithm was 5.39 mm. The conclusion from this study is

  11. Rodents for comparative aging studies: from mice to beavers.

    PubMed

    Gorbunova, Vera; Bozzella, Michael J; Seluanov, Andrei

    2008-09-01

    After humans, mice are the best-studied mammalian species in terms of their biology and genetics. Gerontological research has used mice and rats extensively to generate short- and long-lived mutants, study caloric restriction and more. Mice and rats are valuable model organisms thanks to their small size, short lifespans and fast reproduction. However, when the goal is to further extend the already long human lifespan, studying fast aging species may not provide all the answers. Remarkably, in addition to the fast-aging species, the order Rodentia contains multiple long-lived species with lifespans exceeding 20 years (naked mole-rat, beavers, porcupines, and some squirrels). This diversity opens great opportunities for comparative aging studies. Here we discuss the evolution of lifespan in rodents, review the biology of slow-aging rodents, and show an example of how the use of a comparative approach revealed that telomerase activity coevolved with body mass in rodents. PMID:19424861

  12. Additional EIPC Study Analysis: Interim Report on High Priority Topics

    SciTech Connect

    Hadley, Stanton W

    2013-11-01

    Between 2010 and 2012 the Eastern Interconnection Planning Collaborative (EIPC) conducted a major long-term resource and transmission study of the Eastern Interconnection (EI). With guidance from a Stakeholder Steering Committee (SSC) that included representatives from the Eastern Interconnection States Planning Council (EISPC) among others, the project was conducted in two phases. Phase 1 involved a long-term capacity expansion analysis that involved creation of eight major futures plus 72 sensitivities. Three scenarios were selected for more extensive transmission- focused evaluation in Phase 2. Five power flow analyses, nine production cost model runs (including six sensitivities), and three capital cost estimations were developed during this second phase. The results from Phase 1 and 2 provided a wealth of data that could be examined further to address energy-related questions. A list of 13 topics was developed for further analysis; this paper discusses the first five.

  13. Anatomically ordered tapping interferes more with one-digit addition than two-digit addition: a dual-task fMRI study.

    PubMed

    Soylu, Firat; Newman, Sharlene D

    2016-02-01

    Fingers are used as canonical representations for numbers across cultures. In previous imaging studies, it was shown that arithmetic processing activates neural resources that are known to participate in finger movements. Additionally, in one dual-task study, it was shown that anatomically ordered finger tapping disrupts addition and subtraction more than multiplication, possibly due to a long-lasting effect of early finger counting experiences on the neural correlates and organization of addition and subtraction processes. How arithmetic task difficulty and tapping complexity affect the concurrent performance is still unclear. If early finger counting experiences have bearing on the neural correlates of arithmetic in adults, then one would expect anatomically and non-anatomically ordered tapping to have different interference effects, given that finger counting is usually anatomically ordered. To unravel these issues, we studied how (1) arithmetic task difficulty and (2) the complexity of the finger tapping sequence (anatomical vs. non-anatomical ordering) affect concurrent performance and use of key neural circuits using a mixed block/event-related dual-task fMRI design with adult participants. The results suggest that complexity of the tapping sequence modulates interference on addition, and that one-digit addition (fact retrieval), compared to two-digit addition (calculation), is more affected from anatomically ordered tapping. The region-of-interest analysis showed higher left angular gyrus BOLD response for one-digit compared to two-digit addition, and in no-tapping conditions than dual tapping conditions. The results support a specific association between addition fact retrieval and anatomically ordered finger movements in adults, possibly due to finger counting strategies that deploy anatomically ordered finger movements early in the development. PMID:26410214

  14. Flip This Classroom: A Comparative Study

    ERIC Educational Resources Information Center

    Unruh, Tiffany; Peters, Michelle L.; Willis, Jana

    2016-01-01

    The purpose of this research was to compare the beliefs and attitudes of teachers using the flipped versus the traditional class model. Survey and interview data were collected from a matched sample of in-service teachers representing both models from a large suburban southeastern Texas school district. The Attitude Towards Technology Scale, the…

  15. A COMPARATIVE STUDY OF VIDEO TAPE RECORDINGS.

    ERIC Educational Resources Information Center

    WIENS, JACOB H.

    THE COMPARATIVE EFFECTIVENESS OF PRESENTLY AVAILABLE VIDEO TAPE MACHINES IS REPORTED, FOR THE CONVENIENCE OF SCHOOL ADMINISTRATORS PLANNING TO USE SUCH EQUIPMENT IN EDUCATIONAL PROGRAMS. TESTS WERE CONDUCTED AT THE WIENS ELECTRONIC LABORATORIES. MACHINE BRANDS TESTED WERE AMPEX, CONCORD, MACHTRONICS, PRECISION, RCA, SONY, AND WOLLENSAK. A DETAILED…

  16. Counseling in Costa Rica: A Comparative Study

    ERIC Educational Resources Information Center

    Collier, Crystal

    2013-01-01

    With one of the world's most comprehensive universal healthcare systems, medical tourism in Costa Rica has increased significantly over the past few decades. American tourists save up to 80% of comparative costs for procedures, from heart surgery to root canal treatment. Although many Costa Rican healthcare professionals receive training in North…

  17. [Nutrition pumps in pediatrics: a comparative study].

    PubMed

    Struijk, T; Visser, D; de Schryver, J E; Houwen, R H

    1992-12-01

    Home enteral nutrition as the sole or as an additional way of feeding children is becoming increasingly popular. It can be used in the form of bolus-feeding, or as drip-feeding, either continuous (24 hours) or semicontinuous (nightly). For the latter method usually a feeding pump is used. In the Netherlands several feeding pumps are available, which were tested in this report. These feeding pumps (Compat, Enteroport, Flexiflo Companion, Flocare 500, Frenta Mat, Frenta-System II, Kangaroo 324, Nutromat Päd S, Nutromat S) were investigated for accuracy, available rate-settings, adequate alarming at interruption of the drip feeding, weight and ease of operation. All pumps were tested stationary, and suitable pumps weighing less than 1000 grams were subsequently tested ambulatory. The nine tested pumps were all fairly easy to operate. Three pumps were not suitable for pediatric use, either because the infusion rate was more than 30% out of range (Flexiflo Companion) or because of inadequate rate settings (Nutromat S and Frentasystem II; respectively 20 and 25 ml/hour minimally). Accuracy for the other pumps was always within 10% of the set rate. One pump, the Enteroport, has a rate setting which is suboptimal for pediatric use. In addition this pump does not alarm when the drip feeding is interrupted. The other pumps (Compat, Frenta Mat, Kangaroo 324, Flocare 500, and Nutramat Päd S) are all suitable for pediatric use, both with respect to the rate settings as to the adequate alarming when the drip feeding is interrupted. The Flocare 500 and the Nutromat Päd S, in addition to the Enteroport, have a weight below 1000 grams.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:1488738

  18. Bacterial contamination control mats: a comparative study.

    PubMed Central

    Meddick, H. M.

    1977-01-01

    The ability of six different types of contamination control mats currently in use at the entrances to theatre suites and other clean areas to remove bacteria-carrying particles from theatre trolley wheeels was compared. Marked differences in the effectiveness of this property were obtained; and all mats showed some disadvantages. Modification of one of the mats has resulted in improved efficiency under working conditions. Images Plate 1 PMID:267665

  19. Comparative transport studies of ``1212'' superconductors

    SciTech Connect

    GAPUD,ALBERT; WU,JUDY; YAN,SHAOLIN; XIE,YI-YUAN; KANG,BYEONGWON; SIEGAL,MICHAEL P.; OVERMYER,DONALD L.

    2000-05-17

    HgBa{sub 2}CaCu{sub 2}O{sub 6+{delta}} (Hg-1212) thin films were fabricated by exchanging the TI cations in TlBa{sub 2}CaCu{sub 2}O{sub 7-{delta}} (Tl-1212) thin films with Hg cations, causing a 30-K increase in Tc. To determine how this exchange effects such a Tc increase, the irreversibility lines, temperature dependence of critical current density, and temperature dependence of Hall angle of Hg-1212 and T1-1212 thin films were measured and then compared. The results strongly suggest that the Tc shift is caused by a doubling of charge carrier density.

  20. Comparative study of some new EPR dosimeters

    NASA Astrophysics Data System (ADS)

    Alzimami, K. S.; Maghraby, Ahmed M.; Bradley, D. A.

    2014-02-01

    Investigations have been made of four new radiation dosimetry EPR candidates from the same family of materials: sulfamic acid, sulfanillic acid, homotaurine, and taurine. Mass energy attenuation coefficients, mass stopping power values and the time dependence of the radiation induced radicals are compared. Also investigated are the microwave saturation behavior and the effect of applied modulation amplitude on both peak-to-peak line width (WPP) and peak-to-peak signal height (HPP). The dosimeters are characterized by simple spectra and stable radiation-induced radicals over reasonable durations, especially in taurine dosimeters. Sulfamic acid dosimeters possessed the highest sensitivity followed by taurine and homotaurine and sulfanillic.

  1. A comparative study of primary and secondary stereotypies.

    PubMed

    Ghosh, Debabrata; Rajan, Prashant V; Erenberg, Gerald

    2013-12-01

    This study compares primary stereotypies (repetitive, self-stimulating, and seemingly nonsensical movements that can occur within typically developing children) and secondary stereotypies (those occurring within autistic or mentally retarded children). Utilizing a retrospective chart review from 1995 to 2010, the current study compares primary and secondary stereotypies by the application of a classification system that organizes the movement by its type (motor only, phonic only, mixed) and complexity. In addition, it investigates other parameters associated with the movements such as duration, frequency, age, functional impairment, and progression. The sample group consisted of 28 primary and 28 secondary cases. Primary stereotypies were predominantly motor, simple, of shorter duration, and of less frequency, whereas secondary stereotypies had more vocalization, complexity, longer durations, and higher frequencies. Moreover, functional impairment due to stereotypies was noted in 3 primary and 7 secondary cases, and worsening of stereotypies was noted in 70% of primary versus 44% of secondary cases. PMID:23143719

  2. Comparative study of five blood cardioplegia systems.

    PubMed

    Byrne, C J; Bednarski, A J; Beckley, P D

    1994-12-01

    Five blood cardioplegia delivery systems (Gish Straight Shot, Sorin BCD Advanced, Avecor MYOtherm, Baxter-Bentley HE-30, and Baxter-Bentley HE-30 Gold) were evaluated with respect to ease of rapid priming, coefficient of heat exchange, pressure drop, bubble trap capacity, and priming volume. Each system was placed in a roller pump circuit consisting of source and collection reservoirs, cardioplegia solution, and pre-post system pressure and temperature monitoring sites. A trial was performed on four units of each brand by first priming the circuit with 0.9% NaCl at 200 ml/min. Bovine blood (hematocrit 22%) was then introduced simulating use during bypass. Pressure drops across the heat exchanger were measured at flows of 200, 300, and 400 ml/min and at temperatures of 37 degrees, 19 degrees, and 4 degrees C. Coefficient of heat exchange was determined at 300 ml/min flow. Air was infused into the system to quantify the bubble trap capacity of the heat exchanger module. Priming volume of the entire system and of the heat exchanger module were determined by draining each into a graduated cylinder. The Sorin system had significantly less priming volume when compared to all others. The HE-30 units had significantly higher heat exchange coefficients compared to all other systems. Variability was noted in pressure drop at the highest flows and lowest temperatures. PMID:10150681

  3. A Comparative Study of Compression Video Technology.

    ERIC Educational Resources Information Center

    Keller, Chris A.; And Others

    The purpose of this study was to provide an overview of compression devices used to increase the cost effectiveness of teleconferences by reducing satellite bandwidth requirements for the transmission of television pictures and accompanying audio signals. The main body of the report describes the comparison study of compression rates and their…

  4. Comparative results of 327 chemical carcinogenicity studies.

    PubMed Central

    Haseman, J K; Huff, J E; Zeiger, E; McConnell, E E

    1987-01-01

    The National Cancer Institute (NCI) and the National Toxicology Program (NTP) have carried out a number of laboratory animal carcinogenicity studies and presented the results of these experiments in a series of Technical Reports. This paper tabulates the results of the 327 NCI/NTP studies carried out to date on 308 distinct chemicals, and discusses certain issues relevant to the evaluation of carcinogenicity in these experiments. This compilation of results from NCI/NTP carcinogenicity experiments provides a large database that can be used to study structure-activity correlations, interspecies concordance, and associations between laboratory animal carcinogenicity and other toxicological effects. PMID:3691430

  5. A Comparative Study of Landmine Detection Techniques

    NASA Astrophysics Data System (ADS)

    Kasban, H.; Zahran, O.; Elaraby, Sayed M.; El-Kordy, M.; Abd El-Samie, F. E.

    2010-09-01

    Several countries suffer from the existence of millions of buried landmines in their territories. These landmines have indefinite life, and may still cause horrific personal injuries and economic dislocation for decades after a war has finished. Therefore, there is a growing demand by these countries for reliable landmine inspection systems. There are several landmine detection techniques that can be used for this purpose. Each technique is suitable for detection under some conditions depending on the type of the landmine case, the explosive material, and the soil. This paper presents an overview of some of the existing landmine detection techniques. These techniques are briefly described and their merits and drawbacks are highlighted and compared. The purpose of this comparison is to shows the ideal conditions and the challenges for each technique. Furthermore, a comparison between landmine detection techniques from the points of view of cost, complexity, speed, safety, false alarm rate and effect of environmental conditions is presented.

  6. A comparative evaluation of the effect of various additives on selected physical properties of white mineral trioxide aggregate

    PubMed Central

    Prasad, Anushree; Pushpa, Shankarappa; Arunagiri, Doraiswamy; Sawhny, Asheesh; Misra, Abhinav; Sujatha, Ramamurthy

    2015-01-01

    Aims: This study examined the setting time, compressive strength, and pH of white mineral trioxide aggregate (MTA) mixed with various additives: Calcium chloride (CaCl2), calcium formate (CaF), disodium hydrogen orthophosphate (Na2HPO4). Materials and Methods: Group 1 (Control) was obtained by mixing MTA with distilled water. In Groups 2 and 3, MTA containing 10% CaCl2 and 20% CaF, respectively, was mixed with distilled water. In Group 4, MTA was mixed with 15% Na2HPO4. Setting time, compressive strength, and pH of each group were examined. Statistical Analysis Used: Analysis was done using Statistical Package for Social Sciences (SPSS) version 14. A P-value < 0.05 was considered statistically significant. Comparison of mean values was done using analysis of variance (ANOVA) with post-hoc Games-Howell test. Results: The setting time of test groups were significantly shorter than that of control group (P < 0.001). The compressive strengths of test groups were lower than that of control group (P < 0.001). The pH value obtained for Groups 3 and 4 were higher than that of the control group (P < 0.001). Conclusions: Study result showed that additives significantly reduced the setting time of MTA and also maintained the pH at a high value. However, there was not much improvement in the compressive strength of the material. PMID:26069412

  7. Experimental study of combustion of decane, dodecane and hexadecane with polymeric and nano-particle additives

    NASA Astrophysics Data System (ADS)

    Ghamari, Mohsen; Ratner, Albert

    2015-11-01

    Recent studies have shown that adding combustible nano-particles could have promising effects on increasing burning rate of liquid fuels. Combustible nano-particles could enhance the heat conduction and mixing within the droplet. Polymers have also higher burning rate than regular hydrocarbon fuels because of having the flame closer to the droplet surface. Therefore adding polymeric additive could have the potential to increase the burning rate. In this study, combustion of stationary fuel droplets of n-Decane, n-Dodecane and n-Hexadecane doped with different percentages of a long chain polymer and also a very fine nano carbon was examined and compared with the pure hydrocarbon behavior. In contrast with hydrocarbon droplets with no polymer addition, several zones of combustion including a slow and steady burning zone, a strong swelling zone and a final fast and fairly steady combustion zone were also detected. In addition, increasing polymer percentage resulted in a more extended swelling zone and shorter slow burning zone in addition to a shorter total burning time. Addition of nano-particles also resulted in an overall increased burning rate and shortened burning time which is due to enhanced heat conduction within the droplet.

  8. Comparative study of skew detection algorithms

    NASA Astrophysics Data System (ADS)

    Amin, Adnan; Fischer, Stephen; Parkinson, Anthony F.; Shiu, Ricky

    1996-10-01

    Document image processing has become an increasingly important technology in the automation of office documentation tasks. Automatic document scanners such as text readers and optical character recognition systems are an essential component of systems capable of those tasks. One of the problems in this field is that the document to be read is not always placed correctly on a flat-bed scanner. This means that the document may be skewed on the scanner bed, resulting in a skewed image. This skew has a detrimental effect on document analysis, document understanding, and character segmentation and recognition. Consequently, detecting the skew of a document image and correcting it are important issues in realizing a practical document reader. We describe a new algorithm for skew detection. We then compare the performance and results of this skew detection algorithm to other published methods from O'Gorman, Hinds, Le, Baird, Postl, and Akiyama. Finally, we discuss the theory of skew detection and the different approaches taken to solve the problem of skew in documents. The skew correction algorithm we propose has been shown to be extremely fast, with run times averaging under 0.25 CPU seconds to calculate the angle on a DEC 5000/20 workstation.

  9. Toucan and hornbill beaks: a comparative study.

    PubMed

    Seki, Yasuaki; Bodde, Sara G; Meyers, Marc A

    2010-02-01

    The structure and mechanical behavior of Toco Toucan (Ramphastos toco) and Wreathed Hornbill (Rhyticeros undulatus) beaks were compared. The beak of both species is a sandwich-structured composite, having an exterior, or rhamphotheca, consisting of multiple layers of keratin scales and a core composed of a fibrous network of bony closed-cell foam. The rhamphotheca is an arrangement of approximately 50microm diameter, overlapping, keratin tiles. The hornbill rhamphotheca exhibits a surface morphology on the ridged casque that is distinguishable from that observed on the bill proper. Intermediate filaments in the keratin matrix were observed by transmission electron microscopy. The Young's modulus measurements of toucan rhamphotheca indicate isotropy in longitudinal and transverse directions, whereas those of hornbill rhamphotheca may suggest anisotropy. The compressive response of beak foam is governed by brittle crushing behavior. The crushing strength of hornbill foam is six times higher than that of toucan foam. Micro- and nanoindentation hardness values were measured for rhamphotheca and foam trabeculae of toucan and hornbill specimens. The sandwich design of beaks was analyzed using the Karam-Gibson and Dawson-Gibson models. The presence of a cellular core increases the bending resistance (Brazier moment) by a factor of 3-6 while decreasing the compressive strength by only 50%. PMID:19699818

  10. LES versus DNS: A comparative study

    NASA Technical Reports Server (NTRS)

    Shtilman, L.; Chasnov, J. R.

    1992-01-01

    We have performed Direct Numerical Simulations (DNS) and Large Eddy Simulations (LES) of forced isotropic turbulence at moderate Reynolds numbers. The subgrid scale model used in the LES is based on an eddy viscosity which adjusts instantaneously the energy spectrum of the LES to that of the DNS. The statistics of the large scales of the DNS (filtered DNS field or fDNS) are compared to that of the LES. We present results for the transfer spectra, the skewness and flatness factors of the velocity components, the PDF's of the angle between the vorticity and the eigenvectors of the rate of strain, and that between the vorticity and the vorticity stretching tensor. The above LES statistics are found to be in good agreement with those measured in the fDNS field. We further observe that in all the numerical measurements, the trend was for the LES field to be more gaussian than the fDNS field. Future research on this point is planned.

  11. Children's Friendship Development: A Comparative Study

    ERIC Educational Resources Information Center

    Yu, SeonYeong; Ostrosky, Michaelene M.; Fowler, Susan A.

    2011-01-01

    Establishing friendships is an important developmental goal of early childhood, but little research has addressed ways in which parents support the friendship development of their young children with disabilities. The purpose of this survey study was to explore the support strategies that parents use to facilitate their children's friendships.…

  12. Social Studies. Language Arts: Comparative World Religions.

    ERIC Educational Resources Information Center

    Moore, John A.

    The elective (7-9) course in world religions outlined in this guide is designed to fit the quinmester organization of schools. The course is described as a study of world religions, focusing on religion as an institution in society. It includes effects of religion on people, governments, and internal relations. The guide is divided according to:…

  13. Articulation of Quality Teaching: A Comparative Study

    ERIC Educational Resources Information Center

    Sakarneh, Mohammad

    2015-01-01

    The aim of this study is to describe and then contrast the New South Wales Department of Education and Training's model of quality teaching with the Jordanian Ministry of Education's conception of quality teaching, looking particularly at potential differences in interpretation. A content analysis methodology was used. Each perspective has been…

  14. Metacognition and Group Differences: A Comparative Study

    ERIC Educational Resources Information Center

    Al-Hilawani, Yasser A.

    2014-01-01

    In this study, metacognition refers to performing visual analysis and discrimination of real life events and situations in naïve psychology, naïve physics, and naïve biology domains. It is used, along with measuring reaction time, to examine differences in the ability of four groups of students to select appropriate pictures that correspond with…

  15. Implicature, Pragmatics, and Documentation: A Comparative Study

    ERIC Educational Resources Information Center

    Wright, David

    2008-01-01

    This study investigates the link between the linguistic principles of implicature and pragmatics and software documentation. When implicatures are created in conversation or text, the listener or reader is required to fill in missing information not overtly stated. This information is usually filled in on the basis of previous knowledge or…

  16. Earthquake correlations and networks: A comparative study

    SciTech Connect

    Krishna Mohan, T. R.; Revathi, P. G.

    2011-04-15

    We quantify the correlation between earthquakes and use the same to extract causally connected earthquake pairs. Our correlation metric is a variation on the one introduced by Baiesi and Paczuski [M. Baiesi and M. Paczuski, Phys. Rev. E 69, 066106 (2004)]. A network of earthquakes is then constructed from the time-ordered catalog and with links between the more correlated ones. A list of recurrences to each of the earthquakes is identified employing correlation thresholds to demarcate the most meaningful ones in each cluster. Data pertaining to three different seismic regions (viz., California, Japan, and the Himalayas) are comparatively analyzed using such a network model. The distribution of recurrence lengths and recurrence times are two of the key features analyzed to draw conclusions about the universal aspects of such a network model. We find that the unimodal feature of recurrence length distribution, which helps to associate typical rupture lengths with different magnitude earthquakes, is robust across the different seismic regions. The out-degree of the networks shows a hub structure rooted on the large magnitude earthquakes. In-degree distribution is seen to be dependent on the density of events in the neighborhood. Power laws, with two regimes having different exponents, are obtained with recurrence time distribution. The first regime confirms the Omori law for aftershocks while the second regime, with a faster falloff for the larger recurrence times, establishes that pure spatial recurrences also follow a power-law distribution. The crossover to the second power-law regime can be taken to be signaling the end of the aftershock regime in an objective fashion.

  17. Spatial interpolation of monthly climate data for Finland: comparing the performance of kriging and generalized additive models

    NASA Astrophysics Data System (ADS)

    Aalto, Juha; Pirinen, Pentti; Heikkinen, Juha; Venäläinen, Ari

    2013-04-01

    The Finnish Meteorological Institute has calculated statistics for the new reference period of 1981-2010. During this project, the grid size has been reduced from 10 to 1 km, the evaluation of the interpolation has been improved, and comparisons between different methods has been performed. The climate variables of interest were monthly mean temperature and mean precipitation, for which the spatial variability was explained using auxiliary information: mean elevation, sea percentage, and lake percentage. We compared three methods for spatial prediction: kriging with external drift (KED), generalized additive models (GAM), and GAM combined with residual kriging (GK). Every interpolation file now has attached statistical key figures describing the bias and the normality of the prediction error. According to the cross-validation results, GAM was the best method for predicting mean temperatures, with only very small differences relative to the other methods. For mean precipitation, KED produced the most accurate predictions, followed by GK. In both cases, there was notable seasonal variation in the statistical skill scores. For the new reference period and future interpolations, KED was chosen as the primary method due to its robustness and accuracy.

  18. Comparative study of the 2016 DPRK event

    NASA Astrophysics Data System (ADS)

    Kebede, Fekadu; Jonathan, Ezekiel; Graham, Gerhard

    2016-04-01

    Effective monitoring of any violations of the Comprehensive Nuclear-Test-Ban Treaty (CTBT) depends upon the State Parties' ability to determine the nature of the source of the signals recorded by the IMS stations. Analysis by the IDC of the data gives some of the required information but makes no effort to determine the nature of source as specified by the Treaty. On January 6, 2016 the IMS network of stations recorded unusual seismic event from the DPRK. This was the fourth time that such an event from a man-made event was recorded from this area. Past detections of announced nuclear tests were on 9 October 2006, 25 May 2009, and 12 February 2013. There are a few natural earthquakes that have been recorded in this region. This study presents results of an assessment of waveform data and amplitude spectra obtained from seismic events observed at regional and/or local distance ranges, for both natural and man-made events located in the DPRK. The study reveals that the waveform displays of the four man-made events are practically simple and have nearly the same signature, yet they are significantly different to those of the observed natural earthquakes occurring in the region. The similarities of the waveforms obtained from the man-made events are due to the closeness of the epicentres and hence no difference in path effects for the Stations considered. The computed amplitude spectra of the waveform for the man-made and natural events also show differences in their relative amplitudes between the respective Primary and Secondary seismic phases, indicating that their sources are different. The study clearly shows the importance of studying the signature of the recorded seismic waves to determine the nature of the source of the energy, if it is man-made or natural, particularly for regions where records of natural earthquakes exist. Determination of the nature of source of recorded seismic waves is fundamental to CTBT verification. Thus data observed at regional and

  19. A comparative study of AGN feedback algorithms

    NASA Astrophysics Data System (ADS)

    Wurster, J.; Thacker, R. J.

    2013-05-01

    Modelling active galactic nuclei (AGN) feedback in numerical simulations is both technically and theoretically challenging, with numerous approaches having been published in the literature. We present a study of five distinct approaches to modelling AGN feedback within gravitohydrodynamic simulations of major mergers of Milky Way-sized galaxies. To constrain differences to only be between AGN feedback models, all simulations start from the same initial conditions and use the same star formation algorithm. Most AGN feedback algorithms have five key aspects: the black hole accretion rate, energy feedback rate and method, particle accretion algorithm, black hole advection algorithm and black hole merger algorithm. All models follow different accretion histories, and in some cases, accretion rates differ by up to three orders of magnitude at any given time. We consider models with either thermal or kinetic feedback, with the associated energy deposited locally around the black hole. Each feedback algorithm modifies the region around the black hole to different extents, yielding gas densities and temperatures within r ˜ 200 pc that differ by up to six orders of magnitude at any given time. The particle accretion algorithms usually maintain good agreement between the total mass accreted by dot{M} dt and the total mass of gas particles removed from the simulation, although not all algorithms guarantee this to be true. The black hole advection algorithms dampen inappropriate dragging of the black holes by two-body interactions. Advecting the black hole a limited distance based upon local mass distributions has many desirably properties, such as avoiding large artificial jumps and allowing the possibility of the black hole remaining in a gas void. Lastly, two black holes instantly merge when given criteria are met, and we find a range of merger times for different criteria. This is important since the AGN feedback rate changes across the merger in a way that is dependent

  20. Comparing protein VEGF inhibitors: In vitro biological studies

    SciTech Connect

    Yu, Lanlan; Liang, Xiao Huan; Ferrara, Napoleone

    2011-05-06

    Highlights: {yields} VEGF is a mediator of angiogenesis. {yields} VEGF inhibitors have clinical applications in cancer and eye disorders. {yields} Five protein VEGF inhibitors were compared for their ability to inhibit. {yields} VEGF-induced activities in cultured endothelial cells. -- Abstract: VEGF inhibitors are widely used as a therapy for tumors and intravascular neovascular disorders, but limited and conflicting data regarding their relative biological potencies are available. The purpose of the study is to compare different protein VEGF inhibitors for their ability to inhibit VEGF-stimulated activities. We tested ranibizumab, the full-length variant of ranibizumab (Mab Y0317), bevacizumab, the VEGF-TrapR1R2 and Flt(1-3)-IgG in bioassays measuring VEGF-stimulated proliferation of bovine retinal microvascular endothelial cells or chemotaxis of human umbilical vein endothelial cells (HUVEC). The inhibitors were also compared for their ability to inhibit MAP kinase activation in HUVECs following VEGF addition. Ranibizumab, VEGF-TrapR1R2 and Flt(1-3)-IgG had very similar potencies in the bioassays tested. Bevacizumab was over 10-fold less potent than these molecules. Mab Y0317 was over 30-fold more potent than bevacizumab. The findings reported in this manuscript describe important intrinsic characteristics of several VEGF inhibitors that may be useful to design and interpret preclinical or clinical studies.

  1. Radioactivity of natural and artificial building materials - a comparative study.

    PubMed

    Szabó, Zs; Völgyesi, P; Nagy, H É; Szabó, Cs; Kis, Z; Csorba, O

    2013-04-01

    Building materials and their additives contain radioactive isotopes, which can increase both external and internal radioactive exposures of humans. In this study Hungarian natural (adobe) and artificial (brick, concrete, coal slag, coal slag concrete and gas silicate) building materials were examined. We qualified 40 samples based on their radium equivalent, activity concentration, external hazard and internal hazard indices and the determined threshold values of these parameters. Absorbed dose rate and annual effective dose for inhabitants living in buildings made of these building materials were also evaluated. The calculations are based on (226)Ra, (232)Th and (40)K activity concentrations determined by gamma-ray spectrometry. Measured radionuclide concentrations and hence, calculated indices and doses of artificial building materials show a rather disparate distribution compared to adobes. The studied coal slag samples among the artificial building materials have elevated (226)Ra content. Natural, i.e. adobe and also brick samples contain higher amount of (40)K compared to other artificial building materials. Correlation coefficients among radionuclide concentrations are consistent with the values in the literature and connected to the natural geochemical behavior of U, Th and K elements. Seven samples (coal slag and coal slag concrete) exceed any of the threshold values of the calculated hazard indices, however only three of them are considered to be risky to use according to the fact that the building material was used in bulk amount or in restricted usage. It is shown, that using different indices can lead to different conclusions; hence we recommend considering more of the indices at the same time when building materials are studied. Additionally, adding two times their statistical uncertainties to their values before comparing to thresholds should be considered for providing a more conservative qualification. We have defined radon hazard portion to point

  2. The Effects of Copy, Cover, and Compare with and without Additional Error Drill on Multiplication Fact Fluency and Accuracy

    ERIC Educational Resources Information Center

    Becker, Angela; McLaughlin, Thomas; Weber, Kimberly P.; Gower, Jan

    2009-01-01

    Introduction: The use of copy, cover and compare has been suggested as an effective class-room intervention procedure. The present case report examined the use of copy, cover, and compare with math facts for an elementary student with learning disabilities. Objectives: The purpose of this research was to increase the correct rate and decrease the…

  3. Black Carbon as an Additional Indicator of the Adverse Health Effects of Airborne Particles Compared with PM10 and PM2.5

    PubMed Central

    Hoek, Gerard; Simic-Lawson, Milena; Fischer, Paul; van Bree, Leendert; ten Brink, Harry; Keuken, Menno; Atkinson, Richard W.; Anderson, H. Ross; Brunekreef, Bert; Cassee, Flemming R.

    2011-01-01

    Background: Current air quality standards for particulate matter (PM) use the PM mass concentration [PM with aerodynamic diameters ≤ 10 μm (PM10) or ≤ 2.5 μm (PM2.5)] as a metric. It has been suggested that particles from combustion sources are more relevant to human health than are particles from other sources, but the impact of policies directed at reducing PM from combustion processes is usually relatively small when effects are estimated for a reduction in the total mass concentration. Objectives: We evaluated the value of black carbon particles (BCP) as an additional indicator in air quality management. Methods: We performed a systematic review and meta-analysis of health effects of BCP compared with PM mass based on data from time-series studies and cohort studies that measured both exposures. We compared the potential health benefits of a hypothetical traffic abatement measure, using near-roadway concentration increments of BCP and PM2.5 based on data from prior studies. Results: Estimated health effects of a 1-μg/m3 increase in exposure were greater for BCP than for PM10 or PM2.5, but estimated effects of an interquartile range increase were similar. Two-pollutant models in time-series studies suggested that the effect of BCP was more robust than the effect of PM mass. The estimated increase in life expectancy associated with a hypothetical traffic abatement measure was four to nine times higher when expressed in BCP compared with an equivalent change in PM2.5 mass. Conclusion: BCP is a valuable additional air quality indicator to evaluate the health risks of air quality dominated by primary combustion particles. PMID:21810552

  4. A comparative study of Raman enhancement in capillaries

    NASA Astrophysics Data System (ADS)

    Eftekhari, Fatemeh; Irizar, Juan; Hulbert, Laila; Helmy, Amr S.

    2011-06-01

    This work reports on the comparative studies of Raman enhancement in liquid core waveguides (LCWs). The theoretical considerations that describe Raman enhancement in LCWs is adapted to analyze and compare the performance of hollow core photonic crystal fibers (HCPCFs) to conventional Teflon capillary tubes. The optical losses in both platforms are measured and used to predict their performance for different lengths. The results show that for an optimal waveguide length, two orders of magnitude enhancement in the Raman signal can be achieved for aqueous solutions using HCPCFs. This length, however, cannot be achieved using normal capillary effects. By integrating the interface of the fluidic pump and the HCPCF into a microfluidic chip, we are able to control fluid transport and fill longer lengths of HCPCFs regardless of the viscosity of the sample. The long-term stability and reproducibility of Raman spectra attained through this platform are demonstrated for naphthalenethiol, which is a well-studied organic compound. Using the HCPCF platform, the detection limit of normal Raman scattering in the range of micro-molars has been achieved. In addition to the higher signal-to-noise ratio of the Raman signal from the HCPCF-platform, more Raman modes of naphthalenethiol are revealed using this platform.

  5. What Do We Compare When We Compare Religions? Philosophical Remarks on the Psychology of Studying Comparative Religion Abroad

    ERIC Educational Resources Information Center

    Irvine, Andrew

    2015-01-01

    The issue of comparison is a vexing one in religious and theological studies, not least for teachers of comparative religion in study abroad settings. We try to make familiar ideas fresh and strange, in settings where students may find it hard not to take "fresh" and "strange" as signs of existential threat. The author explores…

  6. Comparative study for better adjuvant with ropivacaine in epidural anesthesia

    PubMed Central

    Soni, Pramila

    2016-01-01

    Background: Better adjuvants for epidural analgesia are still evolving. Dexmedetomidine that is alpha-2 agonist can be used as an adjuvant in epidural analgesia and anesthesia. Aims: The aim of this study was to compare the effect of dexmedetomidine versus clonidine in combination with ropivacaine in epidural anesthesia on intraoperative and postoperative analgesia, to find out the better adjuvant for regional anesthesia. Settings and Design: Randomized control trial. Materials and Methods: Sixty adult patients (18–60 years) with American Society of Anesthesiologists (ASA) 1/ASA 2 grade and undergoing lower abdominal and lower limbs surgeries were included and randomized into three groups of 20 patients each. Group 1 - received ropivacaine with normal saline. Group 2 - received ropivacaine with dexmedetomidine. Group 3 - received ropivacaine with clonidine. Statistical Analysis: Mean and Standard deviation were calculated. All the data were analyzed using analysis of variance and Chi-square test. The value of P< 0.05 was considered significant. Results: All the three groups were comparable with respect to age, sex, and ASA grade. There was statistically significant mean time to reach T10 sensory block level (15.8, 5.7, 9.6 min in Groups 1, 2, and 3, respectively). The maximum duration of analgesia was statistically higher in Group 2 patients (383.7 vs. 365.3 and 280.5 min in Group 3 and Group 1, respectively). The mean time to reach motor block was significantly shorter in Group 2. Side effects were comparable in all groups with statistically insignificant fall in mean arterial pressure and hypotension was noted with Group 2. Conclusion: We concluded that the patients receiving the addition of dexmedetomidine to ropivacaine in epidural anesthesia had a faster onset and longer duration of sensory and motor blockade. Dexmedetomidine in comparison to clonidine had acceptable sedation and hemodynamic stability and minimal dose requirement make very effective adjuvant

  7. Improving wound care simulation with the addition of odor: a descriptive, quasi-experimental study.

    PubMed

    Roberson, Donna W; Neil, Janice A; Bryant, Elizabeth T

    2008-08-01

    Improving problem-solving skills and expertise in complex clinical care provision requires engaging students in the learning process--a challenging goal when clinical practicums and supervisors are limited. High-fidelity simulation has created many new opportunities for educating healthcare professionals. Because addressing malodorous wounds is a common problem that may be difficult to "teach," a descriptive, quasi-experimental simulation study was conducted. Following completion of a wound care simulation and Laerdal's Simulation Experience Evaluation Tool by 137 undergraduate nursing students, 50 control subjects were randomly selected and 49 volunteer students (experimental group) participated in a wound care simulation after one of three cheeses with a strong odor was added to simulate a malodorous wound. Compared to the control group, study group responses were significantly better (P <0.001) for eight of the 12 survey variables tested and indicated the addition of odor was beneficial in enhancing the perceived realism and value of the simulation. Students responded that the addition of odor in the simulation laboratory improved realism and they felt better prepared to handle malodorous wounds in a clinical setting. An unanticipated outcome was the enhanced feeling of involvement associated with paired care teams as opposed to working in larger groups. The results of this study indicate that wound care education outcomes improve when nursing students are able to practice using a multi-sensorial wound care simulation model. PMID:18716340

  8. Study of wood plastic composite in the presence of nitrogen containing additives

    NASA Astrophysics Data System (ADS)

    Ali, K. M. Idriss; Khan, Mubarak A.; Husain, M. M.

    1994-10-01

    Effect of nitrogen-containing additives in the study of wood plastic composites of MMA with simul and mango wood of Bangladesh has been investigated. Nine different additives were used and the additives containing carboamide group induce the highest tensile strength to the composite.

  9. Colloidal dispersions for the delivery of acyclovir: a comparative study.

    PubMed

    Cortesi, Rita; Ravani, Laura; Menegatti, Enea; Drechsler, M; Esposito, Elisabetta

    2011-11-01

    This paper describes a comparative study on the performances of ethosomes and solid lipid nanoparticle as delivery systems for acyclovir. Ethosomes were spontaneously produced by dissolution of phosphatidylcholine and acyclovir in ethanol followed by addition of an aqueous buffer while solid lipid nanoparticle were produced by homogenization and ultrasonication. Both colloidal systems were morphologically characterized by cryo-transmission electron microscopy. The encapsulation efficiency was 94.2±2.8% for ethosomes and 53.2±0.2% for solid lipid nanoparticle. Concerning Z potential, both formulations are close to neutrality. The diffusion coefficients of the drug from ethosomes and solid lipid nanoparticle, determined by a Franz cell method, were 9.4 and 1.2-fold lower as compared to the free acyclovir in solution, thus evidencing the ability of both colloidal systems in enhancing the diffusion of the drug. The antiviral activity against HSV-1 of both systems was tested by plaque reduction assay in monolayer cultures of Vero cells. Data showed that no significant differences in the antiviral activity were observed by acyclovir in the free or loaded forms. Taken together these results, colloidal systems could be interesting to mediate the penetration of acyclovir within Vero cells. PMID:23112407

  10. Lead exposure among five distinct occupational groups: a comparative study.

    PubMed

    Gharaibeh, Mohammad Younis; Alzoubi, Karem Hasan; Khabour, Omar Falah; Khader, Yousef Saleh; Gharaibeh, Mamoun Abdallah; Matarneh, Sulaiman Khalid

    2014-01-01

    This study was conducted to evaluate blood lead concentration among five selected occupational groups. The five groups were: hospital health workers, shop workers, taxi drivers, automobiles mechanics, and wood workers. The groups did not significantly differ among each other in the average of age and work years. ANOVA test revealed significantly higher mean lead blood concentration in taxi drivers, automechanics, and wood workers compared to other groups. Additionally, workers with lead concentration >0.483 umol/L (10μg/dL) were more likely to have frequent muscle pain compared to those with lower concentrations. No association between other symptoms of lead exposure/toxicity and blood lead concentration was detected. In conclusion, special attention must be directed toward lead blood levels and lead poisoning symptoms when examining patients from certain occupational groups such as taxi drivers, automechanics, and wood workers. Special safety precautions and educational programs are also needed to limit the lead exposure in these occupational groups. PMID:24374433

  11. Early parenting styles and sexual offending behavior: A comparative study.

    PubMed

    Sigre-Leirós, Vera; Carvalho, Joana; Nobre, Pedro J

    2016-01-01

    Sexual offenders, in general, report problematic rearing practices from their parents, lacking however more empirical research on this topic regarding particular subtypes of offenders. The current study examined the relationship between early parenting styles and different types of sexual offending. A total of 113 sexual offenders (rapists, pedophilic and nonpedophilic child molesters), and 51 nonsexual offenders completed the EMBU (My Memories of Upbringing), the Brief Symptom Inventory, and the Socially Desirable Response Set Measure. Results showed that rapists were less likely to remember their fathers as being emotionally warm compared with nonsexual offenders and pedophilic child molesters. In addition, compared with rapists, pedophilic offenders perceived their mothers as having been less emotionally warm to them. Overall, results showed that certain developmental experiences with parents were able to distinguish between subtypes of offenders supporting an association between distal interpersonal factors and sexual offending. These findings may have important implications for early intervention and prevention of sexual crimes. Further research using larger samples of pedophilic child molesters is recommended. PMID:27019974

  12. Colloidal Dispersions for the Delivery of Acyclovir: A Comparative Study

    PubMed Central

    Cortesi, Rita; Ravani, Laura; Menegatti, Enea; Drechsler, M.; Esposito, Elisabetta

    2011-01-01

    This paper describes a comparative study on the performances of ethosomes and solid lipid nanoparticle as delivery systems for acyclovir. Ethosomes were spontaneously produced by dissolution of phosphatidylcholine and acyclovir in ethanol followed by addition of an aqueous buffer while solid lipid nanoparticle were produced by homogenization and ultrasonication. Both colloidal systems were morphologically characterized by cryo-transmission electron microscopy. The encapsulation efficiency was 94.2±2.8% for ethosomes and 53.2±0.2% for solid lipid nanoparticle. Concerning Z potential, both formulations are close to neutrality. The diffusion coefficients of the drug from ethosomes and solid lipid nanoparticle, determined by a Franz cell method, were 9.4 and 1.2-fold lower as compared to the free acyclovir in solution, thus evidencing the ability of both colloidal systems in enhancing the diffusion of the drug. The antiviral activity against HSV-1 of both systems was tested by plaque reduction assay in monolayer cultures of Vero cells. Data showed that no significant differences in the antiviral activity were observed by acyclovir in the free or loaded forms. Taken together these results, colloidal systems could be interesting to mediate the penetration of acyclovir within Vero cells. PMID:23112407

  13. Comparative study of different venous reflux duplex quantitation parameters.

    PubMed

    Valentín, L I; Valentín, W H

    1999-09-01

    The objective of this study was to compare different quantitation parameters of venous reflux by duplex scan in different venous disease manifestations. Duplex scan is a new modality to quantify venous reflux. Several studies propose different parameters. In addition, there is controversy about the importance of deep and superficial involvement in different disease manifestations. It is not clear whether there is an increased venous reflux associated with varied clinical stages. Venous conditions were classified in seven stages and their differences for several quantitation variables studied. Most quantitation variables, such as average and peak velocity, average and peak flow, and reflux volume disclosed significantly increased reflux from normal, pain only, and edema group to varicose vein, with or without edema, to lipodermatosclerosis and ulcer groups at every location in the lower extremity. Reflux time was not as consistent as other variables. Totalization of the results of every parameter for the whole extremity points to an increased reflux from pain only to edema and from lipodermatosclerosis to ulcer group. Chronic edema is not usually associated with increased venous reflux. The greater saphenous vein (superficial system) seems to be the main contributor to reflux in all stages of disease. Different quantitation methods of venous reflux are equivalent. Increased deep and superficial reflux and its totalization are associated with a more advanced disease stage. Reflux time may be the least useful variable. Chronic edema is frequently not associated with venous reflux. Greater saphenectomy may be the most useful intervention, even in the presence of deep vein reflux. PMID:10496498

  14. Spectroscopic studies of nucleic acid additions during seed-mediated growth of gold nanoparticles

    PubMed Central

    Tapp, Maeling; Sullivan, Rick; Dennis, Patrick; Naik, Rajesh R.

    2015-01-01

    The effect of adding nucleic acids to gold seeds during the growth stage of either nanospheres or nanorods was investigated using UV-Vis spectroscopy to reveal any oligonucleotide base or structure-specific effects on nanoparticle growth kinetics or plasmonic signatures. Spectral data indicate that the presence of DNA duplexes during seed ageing drastically accelerated nanosphere growth while the addition of single-stranded polyadenine at any point during seed ageing induces nanosphere aggregation. For seeds added to a gold nanorod growth solution, single-stranded polythymine induces a modest blue-shift in the longitudinal peak wavelength. Moreover, a particular sequence comprised of 50% thymine bases was found to induce a faster, more dramatic blue-shift in the longitudinal peak wavelength compared to any of the homopolymer incubation cases. Monomeric forms of the nucleic acids, however, do not yield discernable spectral differences in any of the gold suspensions studied. PMID:25960601

  15. Comparative study of PCA in classification of multichannel EMG signals.

    PubMed

    Geethanjali, P

    2015-06-01

    Electromyographic (EMG) signals are abundantly used in the field of rehabilitation engineering in controlling the prosthetic device and significantly essential to find fast and accurate EMG pattern recognition system, to avoid intrusive delay. The main objective of this paper is to study the influence of Principal component analysis (PCA), a transformation technique, in pattern recognition of six hand movements using four channel surface EMG signals from ten healthy subjects. For this reason, time domain (TD) statistical as well as auto regression (AR) coefficients are extracted from the four channel EMG signals. The extracted statistical features as well as AR coefficients are transformed using PCA to 25, 50 and 75 % of corresponding original feature vector space. The classification accuracy of PCA transformed and non-PCA transformed TD statistical features as well as AR coefficients are studied with simple logistic regression (SLR), decision tree (DT) with J48 algorithm, logistic model tree (LMT), k nearest neighbor (kNN) and neural network (NN) classifiers in the identification of six different movements. The Kruskal-Wallis (KW) statistical test shows that there is a significant reduction (P < 0.05) in classification accuracy with PCA transformed features compared to non-PCA transformed features. SLR with non-PCA transformed time domain (TD) statistical features performs better in accuracy and computational power compared to other features considered in this study. In addition, the motion control of three drives for six movements of the hand is implemented with SLR using TD statistical features in off-line with TMSLF2407 digital signal controller (DSC). PMID:25860845

  16. Impact of contacting study authors to obtain additional data for systematic reviews: diagnostic accuracy studies for hepatic fibrosis

    PubMed Central

    2014-01-01

    Background Seventeen of 172 included studies in a recent systematic review of blood tests for hepatic fibrosis or cirrhosis reported diagnostic accuracy results discordant from 2 × 2 tables, and 60 studies reported inadequate data to construct 2 × 2 tables. This study explores the yield of contacting authors of diagnostic accuracy studies and impact on the systematic review findings. Methods Sixty-six corresponding authors were sent letters requesting additional information or clarification of data from 77 studies. Data received from the authors were synthesized with data included in the previous review, and diagnostic accuracy sensitivities, specificities, and positive and likelihood ratios were recalculated. Results Of the 66 authors, 68% were successfully contacted and 42% provided additional data for 29 out of 77 studies (38%). All authors who provided data at all did so by the third emailed request (ten authors provided data after one request). Authors of more recent studies were more likely to be located and provide data compared to authors of older studies. The effects of requests for additional data on the conclusions regarding the utility of blood tests to identify patients with clinically significant fibrosis or cirrhosis were generally small for ten out of 12 tests. Additional data resulted in reclassification (using median likelihood ratio estimates) from less useful to moderately useful or vice versa for the remaining two blood tests and enabled the calculation of an estimate for a third blood test for which previously the data had been insufficient to do so. We did not identify a clear pattern for the directional impact of additional data on estimates of diagnostic accuracy. Conclusions We successfully contacted and received results from 42% of authors who provided data for 38% of included studies. Contacting authors of studies evaluating the diagnostic accuracy of serum biomarkers for hepatic fibrosis and cirrhosis in hepatitis C patients

  17. Additional diagnostic and clinical value of anti-cyclic citrullinated peptide antibodies compared with rheumatoid factor isotypes in rheumatoid arthritis.

    PubMed

    Vallbracht, Inka; Helmke, Klaus

    2005-07-01

    In the past decade significant advantages have been made in the treatment of rheumatoid arthritis (RA) and therapeutic strategies have changed a lot. These days, highly effective disease modifying anti-rheumatic drugs enable intervention early in the disease process, in order to prevent major joint damage. For years, serological support in the diagnosis of RA has been limited to the presence of rheumatoid factors, although not very specific for RA. During the last years a variety of circulating non-RF antibodies have been discovered and reported to be of potential diagnostic value. CCP2 proved to be a very disease-specific and even sensitive marker for RA. In addition to the diagnostic properties, CCP showed to be a good prognostic marker, CCP helps to predict the erosive or nonerosive progression of the disease, and CCP is already present early in the disease. This diagnostic tool enables the clinician to choose the optimal therapeutic management for each single RA patient. PMID:16081030

  18. A combined toxicity study of zinc oxide nanoparticles and vitamin C in food additives

    NASA Astrophysics Data System (ADS)

    Wang, Yanli; Yuan, Lulu; Yao, Chenjie; Ding, Lin; Li, Chenchen; Fang, Jie; Sui, Keke; Liu, Yuanfang; Wu, Minghong

    2014-11-01

    At present, safety evaluation standards for nanofood additives are made based on the toxic effects of a single additive. Since the size, surface properties and chemical nature influence the toxicity of nanomaterials, the toxicity may have dramatically changed when nanomaterials are used as food additives in a complex system. Herein, we investigated the combined toxicity of zinc oxide nanoparticles (ZnO NPs) and vitamin C (Vc, ascorbic acid). The results showed that Vc increased the cytotoxicity significantly compared with that of the ZnO only NPs. When the cells were exposed to ZnO NPs at a concentration less than 15 mg L-1, or to Vc at a concentration less than 300 mg L-1, there was no significant cytotoxicity, both in the case of gastric epithelial cell line (GES-1) and neural stem cells (NSCs). However, when 15 mg L-1 of ZnO NPs and 300 mg L-1 of Vc were introduced to cells together, the cell viability decreased sharply indicating significant cytotoxicity. Moreover, the significant increase in toxicity was also shown in the in vivo experiments. The dose of the ZnO NPs and Vc used in the in vivo study was calculated according to the state of food and nutrition enhancer standard. After repeated oral exposure to ZnO NPs plus Vc, the injury of the liver and kidneys in mice has been indicated by the change of these indices. These findings demonstrate that the synergistic toxicity presented in a complex system is essential for the toxicological evaluation and safety assessment of nanofood.At present, safety evaluation standards for nanofood additives are made based on the toxic effects of a single additive. Since the size, surface properties and chemical nature influence the toxicity of nanomaterials, the toxicity may have dramatically changed when nanomaterials are used as food additives in a complex system. Herein, we investigated the combined toxicity of zinc oxide nanoparticles (ZnO NPs) and vitamin C (Vc, ascorbic acid). The results showed that Vc increased the

  19. Technology-Enhanced Consultation in Counselling: A Comparative Study

    ERIC Educational Resources Information Center

    Astramovich, Randall L.; Jones, W. Paul; Coker, J. Kelly

    2004-01-01

    Two quasi-experimental studies comparing technology-enhanced counselling consultation were conducted with a sample of 147 students enrolled in an undergraduate counselling and consultation course for elementary and secondary teachers. Study 1 (N = 76) compared the effectiveness of counselling consultation using telephone, text chat, or text chat…

  20. [Studies of Student Performance on the Comparative Guidance Placement Program.

    ERIC Educational Resources Information Center

    Reed, M. Douglas

    Data from the College Entrance Examination Board's Comparative Guidance and Placement (CGP) Program were used in these two studies of students at Central Virginia Community College (CVCC). In the first study, 1971 fall quarter performance in specific courses and in all courses was compared to CGP performance. The conclusions indicate that: (1) CGP…

  1. Additional follow-up telephone counselling and initial smoking relapse: a longitudinal, controlled study

    PubMed Central

    Wu, Lei; He, Yao; Jiang, Bin; Zuo, Fang; Liu, Qinghui; Zhang, Li; Zhou, Changxi

    2016-01-01

    Objectives Smoking cessation services can help smokers to quit; however, many smoking relapse cases occur over time. Initial relapse prevention should play an important role in achieving the goal of long-term smoking cessation. Several studies have focused on the effect of extended telephone support in relapse prevention, but the conclusions remain conflicting. Design and setting From October 2008 to August 2013, a longitudinal, controlled study was performed in a large general hospital of Beijing. Participants The smokers who sought treatment at our smoking cessation clinic were non-randomised and divided into 2 groups: face-to-face individual counselling group (FC group), and face-to-face individual counselling plus telephone follow-up counselling group (FCF group). No pharmacotherapy was offered. Outcomes The timing of initial smoking relapse was compared between FC and FCF groups. Predictors of initial relapse were investigated during the first 180 days, using the Cox proportional hazards model. Results Of 547 eligible male smokers who volunteered to participate, 457 participants (117 in FC group and 340 in FCF group) achieved at least 24 h abstinence. The majority of the lapse episodes occurred during the first 2 weeks after the quit date. Smokers who did not receive the follow-up telephone counselling (FC group) tended to relapse to smoking earlier than those smokers who received the additional follow-up telephone counselling (FCF group), and the log-rank test was statistically significant (p=0.003). A Cox regression model showed that, in the FCF group, being married, and having a lower Fagerström test score, normal body mass index and doctor-diagnosed tobacco-related chronic diseases, were significantly independent protective predictors of smoking relapse. Conclusions Within the limitations of this study, it can be concluded that additional follow-up telephone counselling might be an effective strategy in preventing relapse. Further research is still

  2. Serum Potassium and Glucose Regulation in the ADDITION-Leicester Screening Study

    PubMed Central

    Carter, Patrice; Bodicoat, Danielle H.; Quinn, Lauren M.; Zaccardi, Francesco; Webb, David R.; Khunti, Kamlesh; Davies, Melanie J.

    2015-01-01

    Introduction. Previous observational studies have shown conflicting results between plasma K+ concentrations and risk of type 2 diabetes. To help clarify the evidence we aimed to determine whether an association existed between serum K+ and glucose regulation within a UK multiethnic population. Methods. Participants were recruited as part of the ADDITION Leicester study, a population based screening study. Individuals from primary care between the age of 40 and 75 years if White European or 25 and 75 years if South Asian or Afro Caribbean were recruited. Tests for associations between baseline characteristics and K+ quartiles were conducted using linear regression models. Results. Data showed individuals in the lowest K+ quartile had significantly greater 2-hour glucose levels (0.53 mmol/L, 95% CI: 0.36 to 0.70, P ≤ 0.001) than those in the highest K+ quartile. This estimation did not change with adjustment for potential confounders. Conversely, participants in the lowest K+ quartile had a 0.14% lower HbA1c (95% CI −0.19 to −0.10: P ≤ 0.001) compared to those in the highest K+ quartile. Conclusion. This cross-sectional analysis demonstrated that lower K+ was associated with greater 2 hr glucose. The data supports the possibility that K+ may influence glucose regulation and further research is warranted. PMID:25883988

  3. Comparative study of forensic psychiatric system between China and America.

    PubMed

    Li, Gangqin; Gutheil, Thomas G; Hu, Zeqing

    2016-01-01

    Laws and regulations about the forensic psychiatric systems in China and America were compared, and suggestions for improving the forensic psychiatric system of China were provided. There are many differences regarding the role of the forensic psychiatrist, the initiation of the assessment and the admission of expert opinion because of elements in the legal systems in China and America. The Chinese system has the advantages of objectivity, cost saving and high efficiency; but it has deficiencies in procedural justice and the admission of expert opinion. China can persist with the current system while taking measures to give more rights to the litigants to participate in their assessment, and while improving the quality and utility of the expert opinion; however, this review article will compare broadly the two systems without addressing human rights issues or procedural justice issues, nor will it presume to address the entirety of Chinese systems. In addition, China is developing its legal system for dealing with the mentally ill defendant in situations involving the criminal justice system and civil commitment. Although China enacted new laws regarding the mandatory treatment for the mentally ill, both in criminal and civil systems, there remain many aspects to be improved, including but not limited to a system of review of the decision to detain a patient on psychiatric grounds, and the need for provisions in the laws preventing indefinite detention. From this viewpoint, America's laws and regulations are instructive for us, in matters such as the method of dealing with the mentally ill defendant who is "incompetent to stand trial", "not guilty only by reason of insanity" or "guilty but mentally ill". The conditional release of the committed mentally ill person and the special programs in the forensic security hospital are all worthy of study by China in order to manage the mentally ill offender and to reduce the recidivism rate. PMID:27292971

  4. Liposomes- and ethosomes-associated distamycins: a comparative study.

    PubMed

    Cortesi, Rita; Romagnoli, Romeo; Drechsler, Markus; Menegatti, Enea; Zaid, Abdel N; Ravani, Laura; Esposito, Elisabetta

    2010-12-01

    The present article describes a comparative study of the performances of liposomes and ethosomes as specialized delivery systems for distamycin A (DA) and two of its derivatives. Liposomes and ethosomes were prepared by classical methods, extruded through polycarbonate filters, and characterized in terms of dimensions, morphology, and encapsulation efficiency. It was found that DA was associated with vesicles (either liposomes or ethosomes) by around 16.0%, while both derivatives of DA showed a percentage of association around 80% in the case of liposomes and around 50% in the case of ethosomes. In vitro antiproliferative activity experiments performed on cultured human and mouse leukemic cells demonstrated that vesicles were able to increase the activity of both derivatives of DA. In addition, it was demonstrated that the aging of both liposomes- and ethosomes-associated distamycin suspensions did not heavily influence the vesicle size, while all samples showed a relevant drug leakage with time. Moreover, according to the different physicochemical characteristics of DA and its derivatives (i.e., log P), vesicle-associated DA showed the highest loss of drug with respect to both its derivatives. In conclusion, the enhancement of drug activity expressed by these specialized delivery systems-associated DD could be interesting to obtain an efficient therapeutic effect aimed at reducing or minimizing toxic effects occurring with distamycins administration. PMID:19961302

  5. The minds of gods: a comparative study of supernatural agency.

    PubMed

    Purzycki, Benjamin Grant

    2013-10-01

    The present work is the first study to systematically compare the minds of gods by examining some of the intuitive processes that guide how people reason about them. By examining the Christian god and the spirit-masters of the Tyva Republic, it first confirms that the consensus view of the Christian god's mind is one of omniscience with acute concern for interpersonal social behavior (i.e., moral behaviors) and that Tyvan spirit-masters are not as readily attributed with knowledge or concern of moral information. Then, it reports evidence of a moralization bias of gods' minds; American Christians who believe that God is omniscient rate God as more knowledgeable of moral behaviors than nonmoral information. Additionally, Tyvans who do not readily report pro- or antisocial behavior among the things that spirit-masters care about will nevertheless rate spirit-masters' knowledge and concern of moral information higher than nonmoral information. However, this knowledge is distributed spatially; the farther away from spirits' place of governance a moral behavior takes place, the less they know and care about it. Finally, the wider the breadth of knowledge Tyvans attribute to spirit-masters, the more they attribute moral concern for behaviors that transpire beyond their jurisdiction. These results further demonstrate that there is a significant gulf between expressed beliefs and intuitive religious cognition and provides evidence for a moralization bias of gods' minds. PMID:23891826

  6. Teacher Training and Multiculturalism: National Studies. Studies in Comparative Education.

    ERIC Educational Resources Information Center

    Gagliardi, Raul, Ed.

    This book presents outcomes of UNESCO (United Nations Educational, Scientific, and Cultural Organization) studies on teacher training in eight countries (Bolivia, the Czech Republic, Jordan, Lebanon, Mauritius, Poland, Senegal, and Tunisia) representing different levels of development and different regions of the world but who are facing a common…

  7. 7 CFR 1710.253 - Engineering and cost studies-addition of generation capacity.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 11 2013-01-01 2013-01-01 false Engineering and cost studies-addition of generation... TO ELECTRIC LOANS AND GUARANTEES Construction Work Plans and Related Studies § 1710.253 Engineering... engineering and cost studies as specified by RUS. The studies shall cover a period from the beginning of...

  8. 7 CFR 1710.253 - Engineering and cost studies-addition of generation capacity.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 11 2010-01-01 2010-01-01 false Engineering and cost studies-addition of generation... TO ELECTRIC LOANS AND GUARANTEES Construction Work Plans and Related Studies § 1710.253 Engineering... engineering and cost studies as specified by RUS. The studies shall cover a period from the beginning of...

  9. From Comparative Education to Comparative Pedagogy: A Physical Education Case Study

    ERIC Educational Resources Information Center

    Georgakis, Steve; Graham, Jessica

    2016-01-01

    In the last two decades forces of globalization and the rise of and access to information technology have transformed the nature of educational research. Traditional disciplines such as comparative education have not been immune to these transformational impacts. Although one might expect globalization to promote the study of comparative…

  10. A Comparative Study of Document Retrieval Systems of Nursing Interest.

    ERIC Educational Resources Information Center

    Saba, Virginia Kathleen Joseph

    Intended to provide the nursing community with a comparative analysis of four major computerized document retrieval systems and one manual system providing coverage of the nursing literature, this study compares the indexing vocabulary, database coverage, and retrieval performance of the Educational Resource Information Center (ERIC),…

  11. A Comparative Study of Croatian and Hungarian EFL Students

    ERIC Educational Resources Information Center

    Mihaljevic Djigunovic, Jelena; Nikolov, Marianne; Otto, Istvan

    2008-01-01

    This comparative research aims to provide insights into how Croatian and Hungarian 8th graders' proficiency in English as a foreign language (EFL) compares to one another in relation to organizational macro factors. A total of 717 14-year-old students participated in the study in two neighboring regions and towns of Croatia and Hungary examining…

  12. Mobile Learning vs. Traditional Classroom Lessons: A Comparative Study

    ERIC Educational Resources Information Center

    Furió, D.; Juan, M.-C.; Seguí, I.; Vivó, R.

    2015-01-01

    Different methods can be used for learning, and they can be compared in several aspects, especially those related to learning outcomes. In this paper, we present a study in order to compare the learning effectiveness and satisfaction of children using an iPhone game for learning the water cycle vs. the traditional classroom lesson. The iPhone game…

  13. Assistance to Libraries in Developing Nations: Papers on Comparative Studies.

    ERIC Educational Resources Information Center

    Williamson, William L., Ed.

    The papers presented at a one day workshop on the aspects of comparative librarianship are presented in this volume. The topics discussed are: (1) Methods and Evidence in Comparative Studies; (2) Social Change and Library Development; (3) Library Development in Latin America, a Scalogram; (4) Cross-Cultural Aspects of Assistance to Developing…

  14. [Comparative study on nutmeg, mace and their processed products].

    PubMed

    Jia, T; Wang, Z; Wang, Y; Li, J

    1997-09-01

    The contents of volatile oil, myristicin, safrol and methyleugenol, as well as the composition and content of fatty oil in nutmeg, mace and their processed products were comparatively studied. The composition of volatile oil and the detection of trimyristin were compared by TLC. A scientific basis for the development and application of mace has thus been provided. PMID:11038942

  15. Comparative Studies in Adult Education--A Review.

    ERIC Educational Resources Information Center

    Charters, Alexander N.

    One of the most important recent developments in comparative adult education (CAE) has been the formation in 1987 of the Committee for Study and Research in Comparative Adult Education (CSRCAE), jointly founded by the International Council of Adult Education and the International Congress of University Adult Education. The Committee continues to…

  16. Benefits of Aldosterone Receptor Antagonism in Chronic Kidney Disease (BARACK D) trial–a multi-centre, prospective, randomised, open, blinded end-point, 36-month study of 2,616 patients within primary care with stage 3b chronic kidney disease to compare the efficacy of spironolactone 25 mg once daily in addition to routine care on mortality and cardiovascular outcomes versus routine care alone: study protocol for a randomized controlled trial

    PubMed Central

    2014-01-01

    Background Chronic kidney disease (CKD) is common and increasing in prevalence. Cardiovascular disease (CVD) is a major cause of morbidity and death in CKD, though of a different phenotype to the general CVD population. Few therapies have proved effective in modifying the increased CVD risk or rate of renal decline in CKD. There are accumulating data that aldosterone receptor antagonists (ARA) may offer cardio-protection and delay renal impairment in patients with the CV phenotype in CKD. The use of ARA in CKD has therefore been increasingly advocated. However, no large study of ARA with renal or CVD outcomes is underway. Methods The study is a prospective randomised open blinded endpoint (PROBE) trial set in primary care where patients will mainly be identified by their GPs or from existing CKD lists. They will be invited if they have been formally diagnosed with CKD stage 3b or there is evidence of stage 3b CKD from blood results (eGFR 30–44 mL/min/1.73 m2) and fulfil the other inclusion/exclusion criteria. Patients will be randomised to either spironolactone 25 mg once daily in addition to routine care or routine care alone and followed-up for 36 months. Discussion BARACK D is a PROBE trial to determine the effect of ARA on mortality and cardiovascular outcomes (onset or progression of CVD) in patients with stage 3b CKD. Trial registration EudraCT: 2012-002672-13 ISRTN: ISRCTN44522369 PMID:24886488

  17. Comparative Mirror Cleaning Study: 'A Study on Removing Particulate Contamination'

    NASA Technical Reports Server (NTRS)

    Houston, Karrie

    2007-01-01

    The cleanliness of optical surfaces is recognized as an industry-wide concern for the performance of optical devices such as mirrors and telescopes, microscopes and lenses, lasers and interferometers, and prisms and optical filters. However, no standard has been established for optical cleaning and there is no standard definition of a 'clean' optical element. This study evaluates the effectiveness of commonly used optical cleaning techniques based on wafer configuration, contamination levels, and the number and size of removed particles. It is concluded that cleaning method and exposure time play a significant factor in obtaining a high removal percentage. The detergent bath and solvent rinse method displayed an increase in effective removal percentage as the contamination exposure increased. Likewise, CO2 snow cleaning showed a relatively consistent cleaning effectiveness. The results can help ensure mission success to flight projects developed for the NASA Origins Program. Advantages and disadvantages of each of the optical cleaning methods are described.

  18. Religious Confession and Symptom Severity: A Prospective Comparative Study.

    PubMed

    Rana, Madiha; Rana, Majeed; Herzberg, Philipp Y; Krause, Christin

    2015-12-01

    Little research has been done on comparing confessions regarding mental health. In the present study, 320 people (78 Buddhists, 77 Catholics, 89 Protestants and 79 Muslims) were compared in terms of their symptom severity. Buddhists and Protestants had lower scores than Catholics and Muslims for obsessive-compulsive behavior and hostility. Muslim group had the highest comparative scores for psychoticism. Buddhists and Protestants had comparatively low scores for paranoid ideation and overall symptom severity, with Catholics and Muslims having high ones. Results reveal that confession should be taken in account in psychological research and diagnosis, since it is explicitly associated with psychological well-being. PMID:25204789

  19. Teacher Leader Human Relations Skills: A Comparative Study

    ERIC Educational Resources Information Center

    Roby, Douglas E.

    2012-01-01

    In this study, 142 graduate school teachers working in schools throughout southwestern Ohio assessed their human relation skills. A human relations survey was used for the study, and results were compared with colleagues assessing the teachers in the study. The survey was developed using a Likert-type scale, and was based on key elements affecting…

  20. Effects of Hutchings'"Low Fatigue" Algorithm on Children's Addition Scores Compared Under Varying Conditions of Token Economy Reinforcement and Problem Difficulty.

    ERIC Educational Resources Information Center

    Alessi, Galen James

    This study investigated the effects of the nature of the algorithm, reinforcement, and level of problem difficulty on the ability of fourth graders to solve addition problems as measured by the number of problems correctly solved and the number of columns attempted. Subjects were selected for high scores on a test of basic addition facts; only…

  1. A direct anatomical study of additional renal arteries in a Colombian mestizo population.

    PubMed

    Saldarriaga, B; Pérez, A F; Ballesteros, L E

    2008-05-01

    Traditional anatomy describes each kidney as receiving irrigation from a single renal artery. However, current literature reports great variability in renal blood supply, the number of renal arteries mentioned being the most frequently found variation. Such variation has great implications when surgery is indicated, such as in renal transplants, uroradiological procedures, renovascular hypertension, renal trauma and hydronephrosis. This article pretends to determine the frequency of additional renal arteries and their morphological expression in Colombian population in a cross-sectional study. A total of 196 of renal blocks were analysed from autopsies carried out in the Bucaramanga Institute of Forensic Medicine, Colombia; these renal blocks were processed by the injection- corrosion technique. The average age of the people being studied was 33.8 +/- 15.6 years; 85.4% of them were male and the rest female. An additional renal artery was found in 22.3% of the whole population and two additional ones were found in 2.6% of the same sample. The additional renal artery was most frequently found on the left side. The additional artery arose from the aorta's lateral aspect (52.4%); these additional arteries usually entered the renal parenchyma through the hilum. No difference was established according to gender. Nearly a third of the Colombian population presents one additional renal artery and about 3% of the same population presents two additional renal arteries. Most of them reached the kidney through its hilar region. PMID:18521812

  2. A comparative study between natural and synthetic antioxidants: Evaluation of their performance after incorporation into biscuits.

    PubMed

    Caleja, Cristina; Barros, Lillian; Antonio, Amilcar L; Oliveira, M Beatriz P P; Ferreira, Isabel C F R

    2017-02-01

    Currently, the food industry is focused in replacing the use of synthetic by natural antioxidants. The present study focused on the use of fennel and chamomile extracts, rich in phenolic compounds, as natural antioxidants in biscuits and compared their performance with a synthetic antioxidant widely used, the butylated hydroxyl anisole (BHA). The complete nutritional profile, free sugars, fatty acids and antioxidant activity were determined immediately after baking and also after 15, 30, 45 and 60days of storage. The results showed that the incorporation of natural and synthetic additives did not cause significant changes in colour or in nutritional value of biscuits when compared with control samples. Both natural and synthetic additives conferred similar antioxidant activity to the biscuits. Therefore, natural additives are a more convenient solution for consumers who prefer foods "free" from synthetic additives. Additionally, natural additives were obtained by aqueous extraction, an environment friendly and safe process. PMID:27596429

  3. Grandparents Raising Their Grandchildren: A Comparative Study of Depression

    ERIC Educational Resources Information Center

    Strutton, Joan N.

    2010-01-01

    There has been a steady increase in the United States in recent decades of grandparents raising their grandchildren. The aim of this study was to determine if depression levels of grandparents raising their grandchildren and depression levels of traditional grandparents differ. Additionally, the extent of the relationship to depression scores by…

  4. Comparative Study of Bio-implantable Acoustic Generator Architectures

    NASA Astrophysics Data System (ADS)

    Christensen, D.; Roundy, S.

    2013-12-01

    This paper is a comparative study of the design spaces of two bio-implantable acoustically excited generator architectures: the thickness-stretch-mode circular piezoelectric plate and the bending-mode unimorph piezoelectric diaphragm. The generators are part of an acoustic power transfer system for implanted sensors and medical devices such as glucose monitors, metabolic monitors, drug delivery systems, etc. Our studies indicate that at small sizes the diaphragm architecture outperforms the plate architecture. This paper will present the results of simulation studies and initial experiments that explore the characteristics of the two architectures and compare their performance.

  5. Sustainability of Social Programs: A Comparative Case Study Analysis

    ERIC Educational Resources Information Center

    Savaya, Riki; Spiro, Shimon; Elran-Barak, Roni

    2008-01-01

    The article reports on the findings of a comparative case study of six projects that operated in Israel between 1980 and 2000. The study findings identify characteristics of the programs, the host organizations, and the social and political environment, which differentiated programs that are sustained from those that are not. The findings reaffirm…

  6. Entrepreneurial Training: A Comparative Study across Fifteen European Countries

    ERIC Educational Resources Information Center

    Matricano, Diego

    2014-01-01

    This paper arises from the contents of the Lisbon Strategy, a set of cooperation policies stressing the role of education and training. The findings from a comparative study of the influence that entrepreneurial training--classified as formal or informal--can have on start-up expectations are analysed. The study covers fifteen European countries…

  7. Joachim Wach and the Study of Religion: A Comparative Approach.

    ERIC Educational Resources Information Center

    Georgia, Robert T.

    1992-01-01

    Discusses the life and career of Joachim Wach, a proponent of comparative study of religion (CSR). Reports that Wach envisioned "Religionwissenschaft," a unitary science taking a systematic approach to the study of religion using elements of theology, philosophy, and social science. Presents Wach's "basic and eternal" questions on ultimate…

  8. Political Ideology: A Comparative Study of Three Chicano Youth Organizations.

    ERIC Educational Resources Information Center

    Garcia, Richard A.

    The study investigated the political ideology of three Chicano youth groups in El Paso, Texas: Mexican American Youth Association (MAYA), Mexican American Political Association (MAPA), and the Alianza. Purpose of the study was to identify and compare the political ideas and attitudes of the three organizations. Questionnaires were administered to…

  9. Wage Rate Comparability Review Washington State Work Study Program.

    ERIC Educational Resources Information Center

    Washington State Higher Education Coordinating Board, Olympia.

    Washington State's Higher Education Coordinating Board undertook a review of the State Work Study (SWS) program requirements related to the classification and compensation of SWS positions at public colleges and universities. A task force studying wage rate comparability was convened to review statutory directives related to this issue and to…

  10. Living With and Learning about Radioactivity: A Comparative Conceptual Study.

    ERIC Educational Resources Information Center

    Alsop, Steve

    2001-01-01

    Documents a quasi-scientific comparative study of two groups of 'recent school leavers' in the UK. Studies non-science university undergraduates and explores whether people living with the immediacy and relevance of higher-than-average levels of radioactivity were more knowledgeable and emotionally detached than a similar group removed from this…

  11. A Comparative Study of Students' Achievement in Botany and Zoology

    ERIC Educational Resources Information Center

    Tamir, P.

    1974-01-01

    A comparative study of student achievement in botany and zoology based on data of 10 studies conducted in 20 countries. Up to age 14, students achieve better in zoology; after age 14, students achieve better in botany. Based on the findings, recommendations are suggested regarding curriculum planning, laboratory work and the need for specific…

  12. Additional short-term plutonium urinary excretion data from the 1945-1947 plutonium injection studies

    SciTech Connect

    Moss, W.D.; Gautier, M.A.

    1986-01-01

    The amount of plutonium excreted per day following intravenous injection was shown to be significantly higher than predicted by the Langham power function model. Each of the Los Alamos National Laboratory notebooks used to record the original analytical data was studied for details that could influence the findings. It was discovered there were additional urine excretion data for case HP-3. This report presents the additional data, as well as data on case HP-6. (ACR)

  13. Increased Risk of Additional Cancers Among Patients with Gastrointestinal Stromal Tumors: A Population-Based Study

    PubMed Central

    Murphy, James D.; Ma, Grace L.; Baumgartner, Joel M.; Madlensky, Lisa; Burgoyne, Adam M.; Tang, Chih-Min; Martinez, Maria Elena; Sicklick, Jason K.

    2015-01-01

    Purpose Most gastrointestinal stromal tumors (GIST) are considered non-hereditary or sporadic. However, single-institution studies suggest that GIST patients develop additional malignancies with increased frequencies. We hypothesized that we could gain greater insight into possible associations between GIST and other malignancies using a national cancer database inquiry. Methods Patients diagnosed with GIST (2001–2011) in the Surveillance, Epidemiology, and End Results database were included. Standardized prevalence ratios (SPRs) and standardized incidence ratios (SIRs) were used to quantify cancer risks incurred by GIST patients before and after GIST diagnoses, respectively, when compared with the general U.S. population. Results Of 6,112 GIST patients, 1,047 (17.1%) had additional cancers. There were significant increases in overall cancer rates: 44% (SPR=1.44) before diagnosis and 66% (SIR=1.66) after GIST diagnoses. Malignancies with significantly increased occurrence both before/after diagnoses included other sarcomas (SPR=5.24/SIR=4.02), neuroendocrine-carcinoid tumors (SPR=3.56/SIR=4.79), non-Hodgkin’s lymphoma (SPR=1.69/SIR=1.76), and colorectal adenocarcinoma (SPR=1.51/SIR=2.16). Esophageal adenocarcinoma (SPR=12.0), bladder adenocarcinoma (SPR=7.51), melanoma (SPR=1.46), and prostate adenocarcinoma (SPR=1.20) were significantly more common only before GIST. Ovarian carcinoma (SIR=8.72), small intestine adenocarcinoma (SIR=5.89), papillary thyroid cancer (SIR=5.16), renal cell carcinoma (SIR=4.46), hepatobiliary adenocarcinomas (SIR=3.10), gastric adenocarcinoma (SIR=2.70), pancreatic adenocarcinoma (SIR=2.03), uterine adenocarcinoma (SIR=1.96), non-small cell lung cancer (SIR=1.74), and transitional cell carcinoma of the bladder (SIR=1.65) were significantly more common only after GIST. Conclusion This is the first population-based study to characterize the associations and temporal relationships between GIST and other cancers, both by site and

  14. Computational study of the rate constants and free energies of intramolecular radical addition to substituted anilines

    PubMed Central

    Seddiqzai, Meriam; Dahmen, Tobias; Sure, Rebecca

    2013-01-01

    Summary The intramolecular radical addition to aniline derivatives was investigated by DFT calculations. The computational methods were benchmarked by comparing the calculated values of the rate constant for the 5-exo cyclization of the hexenyl radical with the experimental values. The dispersion-corrected PW6B95-D3 functional provided very good results with deviations for the free activation barrier compared to the experimental values of only about 0.5 kcal mol−1 and was therefore employed in further calculations. Corrections for intramolecular London dispersion and solvation effects in the quantum chemical treatment are essential to obtain consistent and accurate theoretical data. For the investigated radical addition reaction it turned out that the polarity of the molecules is important and that a combination of electrophilic radicals with preferably nucleophilic arenes results in the highest rate constants. This is opposite to the Minisci reaction where the radical acts as nucleophile and the arene as electrophile. The substitution at the N-atom of the aniline is crucial. Methyl substitution leads to slower addition than phenyl substitution. Carbamates as substituents are suitable only when the radical center is not too electrophilic. No correlations between free reaction barriers and energies (ΔG ‡ and ΔG R) are found. Addition reactions leading to indanes or dihydrobenzofurans are too slow to be useful synthetically. PMID:24062821

  15. Computational study of the rate constants and free energies of intramolecular radical addition to substituted anilines.

    PubMed

    Gansäuer, Andreas; Seddiqzai, Meriam; Dahmen, Tobias; Sure, Rebecca; Grimme, Stefan

    2013-01-01

    The intramolecular radical addition to aniline derivatives was investigated by DFT calculations. The computational methods were benchmarked by comparing the calculated values of the rate constant for the 5-exo cyclization of the hexenyl radical with the experimental values. The dispersion-corrected PW6B95-D3 functional provided very good results with deviations for the free activation barrier compared to the experimental values of only about 0.5 kcal mol(-1) and was therefore employed in further calculations. Corrections for intramolecular London dispersion and solvation effects in the quantum chemical treatment are essential to obtain consistent and accurate theoretical data. For the investigated radical addition reaction it turned out that the polarity of the molecules is important and that a combination of electrophilic radicals with preferably nucleophilic arenes results in the highest rate constants. This is opposite to the Minisci reaction where the radical acts as nucleophile and the arene as electrophile. The substitution at the N-atom of the aniline is crucial. Methyl substitution leads to slower addition than phenyl substitution. Carbamates as substituents are suitable only when the radical center is not too electrophilic. No correlations between free reaction barriers and energies (ΔG (‡) and ΔG R) are found. Addition reactions leading to indanes or dihydrobenzofurans are too slow to be useful synthetically. PMID:24062821

  16. 7 CFR 1710.253 - Engineering and cost studies-addition of generation capacity.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 11 2014-01-01 2014-01-01 false Engineering and cost studies-addition of generation capacity. 1710.253 Section 1710.253 Agriculture Regulations of the Department of Agriculture (Continued... TO ELECTRIC LOANS AND GUARANTEES Construction Work Plans and Related Studies § 1710.253...

  17. Evaluating Drugs and Food Additives for Public Use: A Case Studies Approach.

    ERIC Educational Resources Information Center

    Merritt, Sheridan V.

    1980-01-01

    Described is a case study used in an introductory college biology course that provides a basis for generating debate on an issue concerning the regulation of controversial food additives and prescription drugs. The case study contained within this article deals with drug screening, specifically with information related to thalidomide. (CS)

  18. Computational comparative study of microwave probes for plasma density measurement

    NASA Astrophysics Data System (ADS)

    Kim, D. W.; You, S. J.; Kim, J. H.; Chang, H. Y.; Oh, W. Y.

    2016-06-01

    A microwave probe is known to be a suitable method to measure plasma density, even in the processing condition and is widely used in various environments of low-temperature processing plasmas. Various types of microwave probes have been researched and developed to measure the precise plasma density. Extensive research has been conducted to investigate each probes characteristic responding to the plasma parameters (plasma density, electron temperature, pressure, sheath width, and so forth) based on both experiments and simulations. However, a comparative study elucidating the relative characteristics of each probe has not been completed yet, despite the wide applications of the probes in processing plasma. We conduct a comparative study among the microwave probes using the numerical method of three-dimensional finite-difference time-domain simulation. In this study, the microwave probes are compared by investigating the precision of plasma density measurement under a comprehensive range of plasma parameters (plasma density, pressure, and sheath width).

  19. To Flip or Not to Flip? An Exploratory Study Comparing Student Performance in Calculus I

    ERIC Educational Resources Information Center

    Schroeder, Larissa B.; McGivney-Burelle, Jean; Xue, Fei

    2015-01-01

    The purpose of this exploratory, mixed-methods study was to compare student performance in flipped and non-flipped sections of Calculus I. The study also examined students' perceptions of the flipping pedagogy. Students in the flipped courses reported spending, on average, an additional 1-2 hours per week outside of class on course content.…

  20. An Analysis of Language Teacher Education Programs: A Comparative Study of Turkey and Other European Countries

    ERIC Educational Resources Information Center

    Altmisdort, Gonca

    2016-01-01

    The main aim of this study is to analyze and discuss the similarities and the differences between English language teacher educational programs at universities in Turkey, and to identify the undergraduate students' ideas about their current curriculum. In addition to this, the study aims to compare the education of English language teacher…

  1. Maltreated children's representations of mother and an additional caregiver: a longitudinal study.

    PubMed

    Manashko, Shany; Besser, Avi; Priel, Beatriz

    2009-04-01

    In the current longitudinal investigation, we explored the continuity of and changes in the mental representations of the mother and an additional caregiver among forty-five 9- to 11-year-old children who had been severely maltreated and subsequently placed in long-term residential care as well as the relationships between the content and structure of these representations and teacher's assessments of the child's externalizing and internalizing symptoms. At Time 1, a nonmaltreated comparison group was assessed concomitantly. Compared to nonmaltreated children, maltreated children scored higher for externalizing and internalizing symptoms, and their maternal representations were found to be significantly less benevolent and integrated and more punitive. In addition, among the maltreated children, the additional caregiver representations were found to be more benevolent and integrated, and less punitive, than the maternal representations. After 30 months, the maltreated children's levels of externalizing and internalizing symptoms diminished, their maternal representations become more benevolent and less punitive, and the additional caregiver representations became less benevolent. Moreover, the Benevolence of the additional caregiver representation was found to predict these children's changes in externalizing symptoms beyond the effects of their symptomatology and its associations with the Benevolence of these representations at Time 1. PMID:19220720

  2. Comparing comparators: a look at control arms in kidney cancer studies over the years.

    PubMed

    Bracarda, S; Porta, C; Sisani, M; Marrocolo, F; Paglino, C; Hamzaj, A; D Buono, S; Sternberg, C N

    2015-01-01

    In the past decade, an increasing number of frequently positive randomised clinical trials have been completed, allowing new consideration of the present therapeutic armamentarium for advanced renal cell carcinoma. These studies were predominantly designed to compare the experimental drugs with 1 of 2 active control arms: interferon alpha-2a or sorafenib. Different from expectations, the final results of some of these studies were not in line with the predictions, and the reasons have not been fully investigated. Consequently, there is a great need for careful analysis of the studies carried out so far, chiefly the role and validity of the control arms. In this regard, the examination of patient baseline characteristics and other factors of potential interest seems fundamental for a correct analysis of the results of these trials and consequent optimal use of the available targeted agents. PMID:25375270

  3. [TG-FTIR study on pyrolysis of wheat-straw with abundant CaO additives].

    PubMed

    Han, Long; Wang, Qin-Hui; Yang, Yu-Kun; Yu, Chun-Jiang; Fang, Meng-Xiang; Luo, Zhong-Yang

    2011-04-01

    Biomass pyrolysis in presence of abundant CaO additives is a fundamental process prior to CaO sorption enhanced gasification in biomass-based zero emission system. In the present study, thermogravimetric Fourier transform infrared (TG-FTIR) analysis was adopted to examine the effects of CaO additives on the mass loss process and volatiles evolution of wheat-straw pyrolysis. Observations from TG and FTIR analyses simultaneously demonstrated a two-stage process for CaO catalyzed wheat-straw pyrolysis, different from the single stage process for pure wheat-straw pyrolysis. CaO additives could not only absorb the released CO2 but also reduce the yields of tar species such as toluene, phenol, and formic acid in the first stage, resulting in decreased mass loss and maximum mass loss rate in this stage with an increase in CaO addition. The second stage was attributed to the CaCO3 decomposition and the mass loss and maximum mass loss rate increased with increasing amount of CaO additives. The results of the present study demonstrated the great potential of CaO additives to capture CO2 and reduce tars yields in biomass-based zero emission system. The gasification temperature in the system should be lowered down to avoid CaCO3 decomposition. PMID:21714234

  4. SHEEP MOUNTAIN WILDERNESS STUDY AREA AND CUCAMONGA WILDERNESS AND ADDITIONS, CALIFORNIA.

    USGS Publications Warehouse

    Evans, James G.; Ridenour, James

    1984-01-01

    The Sheep Mountain Wilderness Study Area and Cucamonga Wilderness and additions encompass approximately 104 sq mi of the eastern San Gabriel Mountains, Los Angeles and San Bernardino Counties, California. A mineral survey indicates areas of probable and substantiated tungsten and gold resource potential for parts of the Sheep Mountain Wilderness Study Area and an area of probable tungsten and gold resource potential in the Cucamonga Wilderness and additions. The rugged topography, withdrawal of lands from mineral entry to protect watershed, and restricted entry of lands during periods of high fire danger have contributed to the continuing decline in mineral exploration. The geologic setting precludes the presence of energy resources.

  5. [ADJUVANTED INFLUENZA VACCINES: DATA FROM DIRECT COMPARATIVE STUDIES].

    PubMed

    Chernikova, M I; Vasiliev, Yu M

    2015-01-01

    Vaccines are the cornerstone of influenza control, however available vaccines are subject to certain limitations. Adjuvanted vaccines are a promising approach, however available adjuvants have a suboptimal effectiveness and safety profile. Data from direct comparative trials are necessary for selection of optimal adjuvants among currently available and search for novel safe and effective adjuvants for next generation influenza vaccines. Data from published direct comparative studies of adjuvants for influenza vaccines are summarized, a lack of such studies is noted, especially those using adequate methods and designs and comparing adjuvants of major groups (nature/source and mechanism of action). Several promising approaches of adjuvant research and development could be identified: chitosan-based adjuvants, oil-in-water emulsions and multi-component formulations (depot + immune modulating components). PMID:26829860

  6. Comparative study of icy patches on comet nuclei

    NASA Astrophysics Data System (ADS)

    Oklay, Nilda; Pommerol, Antoine; Barucci, Maria Antonietta; Sunshine, Jessica; Sierks, Holger; Pajola, Maurizio

    2016-07-01

    Cometary missions Deep Impact, EPOXI and Rosetta investigated the nuclei of comets 9P/Tempel 1, 103P/Hartley 2 and 67P/Churyumov-Gerasimenko respectively. Bright patches were observed on the surfaces of each of these three comets [1-5]. Of these, the surface of 67P is mapped at the highest spatial resolution via narrow angle camera (NAC) of the Optical, Spectroscopic, and Infrared Remote Imaging System (OSIRIS, [6]) on board the Rosetta spacecraft. OSIRIS NAC is equipped with twelve filters covering the wavelength range of 250 nm to 1000 nm. Various filters combinations are used during surface mapping. With high spatial resolution data of comet 67P, three types of bright features were detected on the comet surface: Clustered, isolated and bright boulders [2]. In the visible spectral range, clustered bright features on comet 67P display bluer spectral slopes than the average surface [2, 4] while isolated bright features on comet 67P have flat spectra [4]. Icy patches observed on the surface of comets 9P and 103P display bluer spectral slopes than the average surface [1, 5]. Clustered and isolated bright features are blue in the RGB composites generated by using the images taken in NIR, visible and NUV wavelengths [2, 4]. This is valid for the icy patches observed on comets 9P and 103P [1, 5]. Spectroscopic observations of bright patches on comets 9P and 103P confirmed the existence of water [1, 5]. There were more than a hundred of bright features detected on the northern hemisphere of comet 67P [2]. Analysis of those features from both multispectral data and spectroscopic data is an ongoing work. Water ice is detected in eight of the bright features so far [7]. Additionally, spectroscopic observations of two clustered bright features on the surface of comet 67P revealed the existence of water ice [3]. The spectral properties of one of the icy patches were studied by [4] using OSIRIS NAC images and compared with the spectral properties of the active regions observed

  7. A Comparative Study of Contract Training in Select Community Colleges.

    ERIC Educational Resources Information Center

    Updike, Katherine May

    In 1991, a study was conducted to compare contract training in selected community colleges providing service to business, industry, and government. A sample of 17 colleges was selected from the League for Innovation Contract Training Professional Network; and phone interviews were conducted with and questionnaires were returned by 16 of the 17…

  8. Louis, Hildegarde, and Mary: A Comparative Study in Infant Bilingualism.

    ERIC Educational Resources Information Center

    Bergman, Coral

    Studies of bilingual infants are in disagreement as to the point at which the child distinguishes two languages in his linguistic environment. In this paper, data from two classic works by linguist-parents on bilingual infants are compared with data collected from the author's own bilingual daughter. Five types of behavior are described which…

  9. Bullying and the Postgraduate Trainee Teacher: A Comparative Study

    ERIC Educational Resources Information Center

    Sewell, Keira; Cain, Tim; Woodgate-Jones, Alex; Srokosz, Anne

    2009-01-01

    In 2001, Maguire published the findings from a survey of the perceptions and experiences of secondary school trainee teachers of adult-adult bullying. The current paper reports on a study which aimed to compare the incidence and nature of bullying of postgraduate trainees in another English teacher training institution with the experiences of…

  10. Decentralized Management in Prison: A Comparative Case Study.

    ERIC Educational Resources Information Center

    Farmer, J. Forbes

    1994-01-01

    Conducted comparative case study of organizational climates in two prisons Findings from 149 staff members and 442 inmates revealed that flattening organizational structure without decentralizing authority seemed to have negative effects on staff supervisory relations and job satisfaction. Inmates reported better quality of life and more effective…

  11. Efficiency study comparing two helicopter planetary reduction stages

    NASA Technical Reports Server (NTRS)

    Krantz, Timothy L.; Handschuh, Robert F.

    1990-01-01

    A study was conducted to compare the efficiency of two helicopter transmission planetary reduction stages. Experimental measurements and analytical predictions were made. The analysis predicted and experiments verified that one planetary stage was a more efficient design due to the type of planet bearing used in the stage. The effects of torque, speed, lubricant type, and lubricant temperature on planetary efficiency are discussed.

  12. Treatment of Conduct Disorders in Childhood: A Comparative Study.

    ERIC Educational Resources Information Center

    Robinson, Elizabeth A.

    Children evidencing conduct disorders comprise the bulk of clinical referrals. Longitudinal studies have found that the prognosis for these children is poor in that the majority exhibit antisocial behavior in adulthood. In order to compare two methods of treatment, relationship-based and contingency management, 53 children (33 boys, 20 girls),…

  13. Comparative Study of Bacterial Growth in Magnet Fields

    NASA Astrophysics Data System (ADS)

    Smith, Derek; Masood, Samina

    It has been shown that magnetic fields affect bacterial growth. A comparative study of growth rates for gram-positive and gram-negative bacteria with different types of magnetic fields is done. Special focus is placed upon growth within liquid media, and the effect of magnetic fields relative to the chosen growth medium is considered.

  14. Comparative Study of Student Support Services of AIOU and UKOU

    ERIC Educational Resources Information Center

    Choudhry, Amtul Hafeez; Gujjar, Aijaz Ahmed; Hafeez, Muhammad Rashid

    2008-01-01

    This paper attempts to compare the availability, quality, similarities and differences of student support services in Allama Iqbal Open University (AIOU) and United Kingdom Open University (UKOU) and also to identify and enlist the deficiencies that AIOU students are facing in the student support services. The study found out that student support…

  15. Research Governance and the Role of Evaluation: A Comparative Study

    ERIC Educational Resources Information Center

    Molas-Gallart, Jordi

    2012-01-01

    Through a comparative study of the United Kingdom and Spain, this article addresses the effect of different research governance structures on the functioning and uses of research evaluation. It distinguishes three main evaluation uses: distributive, improvement, and controlling. Research evaluation in the United Kingdom plays important…

  16. The Syntax of Bilingual Children: A Comparative Study.

    ERIC Educational Resources Information Center

    Van Metre, Patricia D.

    The interview techniques developed by Carol Chomsky were used in a comparative study of the language acquisition of 32 bilingual and monolingual third grade students. After these students were matched for age, socioeconomic status, IQ, family environment (both parents in the home), and reading ability, they were placed in four…

  17. A Comparative Study of the Adjustment of Secondary School Students

    ERIC Educational Resources Information Center

    Devika R.

    2014-01-01

    Education is the ability to meet one's life. How the child adjusts with varying situations determines the success of life. The child's adjustment is determined by a number of factors like Home, Social, Educational and Financial adjustment. The investigator here aims to make a comparative study on the adjustment of secondary school students. The…

  18. It Pays to Compare: An Experimental Study on Computational Estimation

    ERIC Educational Resources Information Center

    Star, Jon R.; Rittle-Johnson, Bethany

    2009-01-01

    Comparing and contrasting examples is a core cognitive process that supports learning in children and adults across a variety of topics. In this experimental study, we evaluated the benefits of supporting comparison in a classroom context for children learning about computational estimation. Fifth- and sixth-grade students (N = 157) learned about…

  19. Political Responses to Reform: A Comparative Case Study.

    ERIC Educational Resources Information Center

    Noblit, George; And Others

    1991-01-01

    Comparative case studies assessed how the micropolitics of educational reform in two elementary schools affected one southeastern district's effort to professionalize teaching. The results indicate that teachers can use micropolitics to resist reform that, in these cases, legitimated centralization and control, and to heighten their control of…

  20. Comparative Studies on Sino-Canadian Higher Education

    ERIC Educational Resources Information Center

    Yang, Hong

    2008-01-01

    Today education is internationalization. Both China and Canada have their own strong merits of higher education. This paper approaches comparative studies on differences of Sino-Canadian higher education from new points, so as to achieve an inspiration to the development of Chinese higher education: preserve relative independence between higher…

  1. Generation 1.5 Written Error Patterns: A Comparative Study

    ERIC Educational Resources Information Center

    Doolan, Stephen M.; Miller, Donald

    2012-01-01

    In an attempt to contribute to existing research on Generation 1.5 students, the current study uses quantitative and qualitative methods to compare error patterns in a corpus of Generation 1.5, L1, and L2 community college student writing. This error analysis provides one important way to determine if error patterns in Generation 1.5 student…

  2. A Study Comparing Electronic Mail and Voice Messaging Channels.

    ERIC Educational Resources Information Center

    Gluck, Myke; And Others

    1991-01-01

    Describes a study that explored differences in computer-mediated communication messaging by comparing electronic mail and voice messaging used for giving directions. Highlights include a computational linguistic framework that examines differences between written and oral English, models of direction provision, and hypotheses based on preliminary…

  3. Using Comparative Online Media to Study the Iraq War

    ERIC Educational Resources Information Center

    Eaton, Jana Sackman

    2004-01-01

    The war in Iraq and the aftermath are receiving media attention around the globe. A plethora of media reports from many other countries is now available online in English. This article recommends possible approaches to developing comparative media studies and provides URLs to specific sources. The NCSS standards addressed by these lessons include:…

  4. A Comparative Study of Two Acoustic Measures of Hypernasality

    ERIC Educational Resources Information Center

    Vogel, Adam P.; Ibrahim, Hasherah M.; Reilly, Sheena; Kilpatrick, Nicky

    2009-01-01

    Purpose: This study aimed to compare 2 quantitative acoustic measures of nasality in children with cleft lip and palate (CLP) and healthy controls using formalized perceptual assessment as a guide. Method: Fifty participants (23 children with CLP and 27 age- and gender-matched healthy controls) aged between 4 and 12 years produced a variety of…

  5. Different Underlying Neurocognitive Deficits in Developmental Dyslexia: A Comparative Study

    ERIC Educational Resources Information Center

    Menghini, D.; Finzi, A.; Benassi, M.; Bolzani, R.; Facoetti, A.; Giovagnoli, S.; Ruffino, M.; Vicari, S.

    2010-01-01

    The aim of this study was to investigate the role of several specific neurocognitive functions in developmental dyslexia (DD). The performances of 60 dyslexic children and 65 age-matched normally reading children were compared on tests of phonological abilities, visual processing, selective and sustained attention, implicit learning, and executive…

  6. A Comparative Study of Students' Attitudes Toward Education.

    ERIC Educational Resources Information Center

    Quintanar, Rosalinda

    The comparative analysis of students' attitudes included Mexican American, Anglo, and Asian students (from Thailand, Taiwan, and the Philippines). A Likert scale was used to measure all attitudes. All analysis performed utilized cross tabulation and chi square. The attitudes studied were reasons for going to college; concept of an educated person…

  7. Comparative Analysis, Global Policy Studies and the Human Condition.

    ERIC Educational Resources Information Center

    Bertsch, Gary K.

    This paper examines the role that comparative analysis and global policy studies can play in explaining the human condition in the contemporary world. It investigates economic well-being, one dimension of the human condition, and examines some of the attributes that represent it and some of the forces that affect it in villages, social groupings,…

  8. Introduction to a Comparative Study of Educational Administration.

    ERIC Educational Resources Information Center

    Lynch, Patrick D.

    Comparative educational administration is not yet a recognized field, although a number of works concerning cross-cultural educational literature are directly applicable to such studies. Four themes are apparent in relevant works. Beginning in the 19th century, the earliest works focused on European schools in the hopes America could learn from…

  9. TRANSMISSION NETWORK PLANNING METHOD FOR COMPARATIVE STUDIES (JOURNAL VERSION)

    EPA Science Inventory

    An automated transmission network planning method for comparative studies is presented. This method employs logical steps that may closely parallel those taken in practice by the planning engineers. Use is made of a sensitivity matrix to simulate the engineers' experience in sele...

  10. Comparative analysis of the space power architecture studies

    NASA Technical Reports Server (NTRS)

    Sovie, Ronald J.

    1988-01-01

    The Strategic Defense Initiative Organization (SDIO) has recently completed the initial phase of Space Power Architecture Studies (SPAS). The initial effort consisted of three major contracted efforts and a comparative analysis performed by the SDIO Independent Evaluation Group (IEG) and the IEG Field Support Team. The purpose of the SPAS effort was to evaluate a wide range of power systems for SDIO applications using a wide range of attributes other than power-system mass and volume. Open cycle, closed cycle, and closed power system/weapon platform concepts were studied. The purpose of this paper is to summarize the salient results of these studies, identify important trends and future study needs.

  11. A comparative study of nuclear accident consequences for Hong Kong

    SciTech Connect

    Ching, E.M.K.; Yeung, Mankit Ray )

    1993-02-01

    A two-dimensional dispersion and consequence model called RADIS has been developed and used to perform a site-specific investigation of the consequences and risks for Hong Kong as a result of a potential accident at the Daya Bay Nuclear Power Station. The study uses the 1986 Hong Kong weather and demographic data to determine the accident consequences for Hong Kong. The overall cumulative occurrence frequency distributions of early fatality, early injury, latent cancer, and thyroid nodule are compared with those of WASH-1400 and a United Kingdom Atomic Energy Authority (UKAEA) study. This study is generally consistent with the WASH-1400 results and exhibits less conservatism than the UKAEA study.

  12. 7 CFR 1710.253 - Engineering and cost studies-addition of generation capacity.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 11 2011-01-01 2011-01-01 false Engineering and cost studies-addition of generation capacity. 1710.253 Section 1710.253 Agriculture Regulations of the Department of Agriculture (Continued) RURAL UTILITIES SERVICE, DEPARTMENT OF AGRICULTURE GENERAL AND PRE-LOAN POLICIES AND PROCEDURES COMMON TO ELECTRIC LOANS AND...

  13. 7 CFR 1710.253 - Engineering and cost studies-addition of generation capacity.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 11 2012-01-01 2012-01-01 false Engineering and cost studies-addition of generation capacity. 1710.253 Section 1710.253 Agriculture Regulations of the Department of Agriculture (Continued) RURAL UTILITIES SERVICE, DEPARTMENT OF AGRICULTURE GENERAL AND PRE-LOAN POLICIES AND PROCEDURES COMMON TO ELECTRIC LOANS AND...

  14. A comparative study about learning styles preferences of two cultures

    NASA Astrophysics Data System (ADS)

    Kutay, Huban

    From an anthropologist's (Maddock, 1981) point of view, "science and science education are cultural enterprises which form a part of the wider cultural matrix of society and educational considerations concerning science must be made in the light of this wider perspective" (p.10). In addition, Spindler (1987) states that teaching science is considered cultural transmission while, Wolcott (1991) focuses on learning science as culture acquisition. In these statements, culture is defined as "an ordered system of meaning and symbols, in terms of which social interaction takes place" (Geertz, 1973). Thus, learning and culture are a partnership. Jones and Fennimore (1990) state: "Every culture brings habits of thought, resources, and context, which have built into them vehicles that promote learning and inquiry. Accordingly, children of any culture can and should have curriculum and instructional practices that draw from that culture." (p.16). Unfortunately, even though this statement is probably accurate, most schools still use the same curriculum, instructional methods, and assessment strategies for all students regardless of their differences in learning styles. The purpose of this study is to identify the relationship between students' learning styles and their culture. This is a correlational study. Does culture limit or expand the learning of individuals? For this study Turkish students who graduated from a Turkish high school and undertook undergraduate education in the United States or finished their undergraduate education in Turkey and pursued graduate education in the United States were identified. These Turkish subjects were compared to American college students through learning styles data and anxiety levels as cultural markers. To identify individuals' learning styles we used the Building Excellence (BE) instrument, which is an adult version of The Learning Style Inventory by Dunn, and Rundle (1996.1997, 1998, 1999, and 2000). BE assesses twenty four

  15. Comparative study of texture detection and classification algorithms

    NASA Astrophysics Data System (ADS)

    Koltsov, P. P.

    2011-08-01

    A description and results of application of the computer system PETRA (performance evaluation of texture recognition algorithms) are given. This system is designed for the comparative study of texture analysis algorithms; it includes a database of textured images and a collection of software implementations of texture analysis algorithms. The functional capabilities of the system are illustrated using texture classification examples. Test examples are taken from the Brodatz album, MeasTech database, and a set of aerospace images. Results of a comparative evaluation of five well-known texture analysis methods are described—Gabor filters, Laws masks, ring/wedge filters, gray-level cooccurrence matrices (GLCMs), and autoregression image model.

  16. A near-infrared spectroscopic study of young field ultracool dwarfs: additional analysis

    NASA Astrophysics Data System (ADS)

    Allers, K. N.; Liu, M. C.

    We present additional analysis of the classification system presented in \\citet{allers13}. We refer the reader to \\citet{allers13} for a detailed discussion of our near-IR spectral type and gravity classification system. Here, we address questions and comments from participants of the Brown Dwarfs Come of Age meeting. In particular, we examine the effects of binarity and metallicity on our classification system. We also present our classification of Pleiades brown dwarfs using published spectra. Lastly, we determine SpTs and calculate gravity-sensitive indices for the BT-Settl atmospheric models and compare them to observations.

  17. Multiparametric PET/CT-perfusion does not add significant additional information for initial staging in lung cancer compared with standard PET/CT

    PubMed Central

    2014-01-01

    Background The purpose of this study was to assess the relationship of CT-perfusion (CTP), 18F-FDG-PET/CT and histological parameters, and the possible added value of CTP to FDG-PET/CT in the initial staging of lung cancer. Methods Fifty-four consecutive patients (median age 65 years, 15 females, 39 males) with suspected lung cancer were evaluated prospectively by CT-perfusion scan and 18F-FDG-PET/CT scan. Overall, 46 tumors were identified. CTP parameters blood flow (BF), blood volume (BV), and mean transit time (MTT) of the tumor tissue were calculated. Intratumoral microvessel density (MVD) was assessed quantitatively. Differences in CTP parameters concerning tumor type, location, PET positivity of lymph nodes, TNM status, and UICC stage were analyzed. Spearman correlation analyses between CTP and 18F-FDG-PET/CT parameters (SUVmax, SUVmean, PETvol, and TLG), MVD, tumor size, and tumor stage were performed. Results The mean BF (mL/100 mL min-1), BV (mL/100 mL), and MTT (s) was 35.5, 8.4, and 14.2, respectively. The BF and BV were lower in tumors with PET-positive lymph nodes (p = 0.02). However, the CTP values were not significantly different among the N stages. The CTP values were not different, depending on tumor size and location. No significant correlation was found between CTP parameters and MVD. Conclusions Overall, the CTP information showed only little additional information for the initial staging compared with standard FDG-PET/CT. Low perfusion in lung tumors might possibly be associated with metabolically active regional lymph nodes. Apart from that, both CTP and 18F-FDG-PET/CT parameter sets may reflect different pathophysiological mechanisms in lung cancer. PMID:24450990

  18. A synchrotron study of microstructure gradient in laser additively formed epitaxial Ni-based superalloy

    NASA Astrophysics Data System (ADS)

    Xue, Jiawei; Zhang, Anfeng; Li, Yao; Qian, Dan; Wan, Jingchun; Qi, Baolu; Tamura, Nobumichi; Song, Zhongxiao; Chen, Kai

    2015-10-01

    Laser additive forming is considered to be one of the promising techniques to repair single crystal Ni-based superalloy parts to extend their life and reduce the cost. Preservation of the single crystalline nature and prevention of thermal mechanical failure are two of the most essential issues for the application of this technique. Here we employ synchrotron X-ray microdiffraction to evaluate the quality in terms of crystal orientation and defect distribution of a Ni-based superalloy DZ125L directly formed by a laser additive process rooted from a single crystalline substrate of the same material. We show that a disorientation gradient caused by a high density of geometrically necessary dislocations and resultant subgrains exists in the interfacial region between the epitaxial and stray grains. This creates a potential relationship of stray grain formation and defect accumulation. The observation offers new directions on the study of performance control and reliability of the laser additive manufactured superalloys.

  19. Microstructural Study Of Zinc Hot Dip Galvanized Coatings with Titanium Additions In The Zinc Melt

    NASA Astrophysics Data System (ADS)

    Konidaris, S.; Pistofidis, N.; Vourlias, G.; Pavlidou, E.; Stergiou, A.; Stergioudis, G.; Polychroniadis, E. K.

    2007-04-01

    Zinc hot-dip galvanizing is a method for protecting iron and steel against corrosion. Galvanizing with pure Zn or Zn with additions like Ni, Al, Pb and Bi has been extensively studied, but there is a lack of scientific information about other additions. The present work examines the effect of a 0.5 wt% Ti addition in the Zn melt. The samples were exposed to accelerated corrosion in a salt spray chamber (SSC). The microstructure and chemical composition of the coatings were determined by Optical Microscopy, XRD and SEM associated with an EDS Analyzer. The results indicate that the coatings have a typical morphology, while Zn-Ti phases were also detected.

  20. A synchrotron study of microstructure gradient in laser additively formed epitaxial Ni-based superalloy

    PubMed Central

    Xue, Jiawei; Zhang, Anfeng; Li, Yao; Qian, Dan; Wan, Jingchun; Qi, Baolu; Tamura, Nobumichi; Song, Zhongxiao; Chen, Kai

    2015-01-01

    Laser additive forming is considered to be one of the promising techniques to repair single crystal Ni-based superalloy parts to extend their life and reduce the cost. Preservation of the single crystalline nature and prevention of thermal mechanical failure are two of the most essential issues for the application of this technique. Here we employ synchrotron X-ray microdiffraction to evaluate the quality in terms of crystal orientation and defect distribution of a Ni-based superalloy DZ125L directly formed by a laser additive process rooted from a single crystalline substrate of the same material. We show that a disorientation gradient caused by a high density of geometrically necessary dislocations and resultant subgrains exists in the interfacial region between the epitaxial and stray grains. This creates a potential relationship of stray grain formation and defect accumulation. The observation offers new directions on the study of performance control and reliability of the laser additive manufactured superalloys. PMID:26446425

  1. A synchrotron study of microstructure gradient in laser additively formed epitaxial Ni-based superalloy

    SciTech Connect

    Xue, Jiawei; Zhang, Anfeng; Li, Yao; Qian, Dan; Wan, Jingchun; Qi, Baolu; Tamura, Nobumichi; Song, Zhongxiao; Chen, Kai

    2015-10-08

    Laser additive forming is considered to be one of the promising techniques to repair single crystal Ni-based superalloy parts to extend their life and reduce the cost. Preservation of the single crystalline nature and prevention of thermal mechanical failure are two of the most essential issues for the application of this technique. Here we employ synchrotron X-ray microdiffraction to evaluate the quality in terms of crystal orientation and defect distribution of a Ni-based superalloy DZ125L directly formed by a laser additive process rooted from a single crystalline substrate of the same material. We show that a disorientation gradient caused by a high density of geometrically necessary dislocations and resultant subgrains exists in the interfacial region between the epitaxial and stray grains. This creates a potential relationship of stray grain formation and defect accumulation. In conclusion, the observation offers new directions on the study of performance control and reliability of the laser additive manufactured superalloys.

  2. Ergonomic intervention, workplace exercises and musculoskeletal complaints: a comparative study

    PubMed Central

    Mehrparvar, Amir Houshang; Heydari, Mohammad; Mirmohammadi, Seyyed Jalil; Mostaghaci, Mehrdad; Davari, Mohammad Hossein; Taheri, Mahmoud

    2014-01-01

    Background: Musculoskeletal disorders are among the most prevalent occupational disorders in different jobs such as office work. Some interventions such as ergonomic modifications and workplace exercises are introduced as the methods for alleviating these disorders. In this study we compared the effect of ergonomic modifications and workplace exercises on musculoskeletal pain and discomfort in a group of office workers. Methods: In an interventional study on office workers, the effect of two interventions was compared. Ergonomic modification consisted of correcting the arrangement of workstation and changing some equipment; workplace exercises included stretching exercises focusing on neck, shoulders, low back, and hand and wrist. Musculoskeletal complaints were assessed and compared before and after 1 month interventions. Results: The frequency of musculoskeletal complaints was high before the study. Both interventions significantly reduced complaints in a similar manner except for low back pain which was reduced in exercise group more than the other group. Conclusion: In this study we found a beneficial short-term effect for both ergonomic modifications and stretching work-place exercises on reducing musculoskeletal pain in office workers. PMID:25405134

  3. Summary of Previous Chamber or Controlled Anthrax Studies and Recommendations for Possible Additional Studies

    SciTech Connect

    Piepel, Gregory F.; Amidan, Brett G.; Morrow, Jayne B.

    2010-12-29

    This report and an associated Excel file(a) summarizes the investigations and results of previous chamber and controlled studies(b) to characterize the performance of methods for collecting, storing and/or transporting, extracting, and analyzing samples from surfaces contaminated by Bacillus anthracis (BA) or related simulants. This report and the Excel are the joint work of the Pacific Northwest National Laboratory (PNNL) and the National Institute of Standards and Technology (NIST) for the Department of Homeland Security, Science and Technology Directorate. The report was originally released as PNNL-SA-69338, Rev. 0 in November 2009 with limited distribution, but was subsequently cleared for release with unlimited distribution in this Rev. 1. Only minor changes were made to Rev. 0 to yield Rev. 1. A more substantial update (including summarizing data from other studies and more condensed summary tables of data) is underway

  4. Studies of levels of biogenic amines in meat samples in relation to the content of additives.

    PubMed

    Jastrzębska, Aneta; Kowalska, Sylwia; Szłyk, Edward

    2016-01-01

    The impact of meat additives on the concentration of biogenic amines and the quality of meat was studied. Fresh white and red meat samples were fortified with the following food additives: citric and lactic acids, disodium diphosphate, sodium nitrite, sodium metabisulphite, potassium sorbate, sodium chloride, ascorbic acid, α-tocopherol, propyl 3,4,5-trihydroxybenzoate (propyl gallate) and butylated hydroxyanisole. The content of spermine, spermidine, putrescine, cadaverine, histamine, tyramine, tryptamine and 2-phenylethylamine was determined by capillary isotachophoretic methods in meat samples (fresh and fortified) during four days of storage at 4°C. The results were applied to estimate the impact of the tested additives on the formation of biogenic amines in white and red meat. For all tested meats, sodium nitrite, sodium chloride and disodium diphosphate showed the best inhibition. However, cadaverine and putrescine were characterised by the biggest changes in concentration during the storage time of all the additives. Based on the presented data for the content of biogenic amines in meat samples analysed as a function of storage time and additives, we suggest that cadaverine and putrescine have a significant impact on meat quality. PMID:26515667

  5. Comparative study of turbulence models in predicting hypersonic inlet flows

    NASA Technical Reports Server (NTRS)

    Kapoor, Kamlesh; Anderson, Bernhard H.; Shaw, Robert J.

    1992-01-01

    A numerical study was conducted to analyze the performance of different turbulence models when applied to the hypersonic NASA P8 inlet. Computational results from the PARC2D code, which solves the full two-dimensional Reynolds-averaged Navier-Stokes equation, were compared with experimental data. The zero-equation models considered for the study were the Baldwin-Lomax model, the Thomas model, and a combination of the Baldwin-Lomax and Thomas models; the two-equation models considered were the Chien model, the Speziale model (both low Reynolds number), and the Launder and Spalding model (high Reynolds number). The Thomas model performed best among the zero-equation models, and predicted good pressure distributions. The Chien and Speziale models compared very well with the experimental data, and performed better than the Thomas model near the walls.

  6. Comparative study of turbulence models in predicting hypersonic inlet flows

    NASA Technical Reports Server (NTRS)

    Kapoor, Kamlesh; Anderson, Bernhard H.; Shaw, Robert J.

    1992-01-01

    A numerical study was conducted to analyze the performance of different turbulence models when applied to the hypersonic NASA P8 inlet. Computational results from the PARC2D code, which solves the full two-dimensional Reynolds-averaged Navier-Stokes equation, were compared with experimental data. The zero-equation models considered for the study were the Baldwin-Lomax model, the Thomas model, and a combination of the Baldwin-Lomax and Thomas models; the two-equation models considered were the Chien model, the Speziale model (both low Reynolds number), and the Launder and Spalding model (high Reynolds number). The Thomas model performed best among the zero-equation models, and predicted good pressure distributions. The Chien and Speziale models compared wery well with the experimental data, and performed better than the Thomas model near the walls.

  7. a Study on the Role of Sintering Additives for Fabrication of sic Ceramic

    NASA Astrophysics Data System (ADS)

    Yoon, Han Ki; Lee, Young Ju; Cho, Ho Jun; Kim, Tae Gyu

    Silicon carbide (SiC) materials have been extensively studied for high temperature components in advanced energy system and advanced gas turbine. The SiC ceramics have been fabricated by a NITE (Nano Infiltration Transient Eutectic Phase) Process, using Nano-SiC powder. The sintering additives used for forming liquid phase under sintering process, used the sintering additives ratios were an Al2O3-Y2O3 system or add SiO2 contents. A major R&D focus for the SiC ceramics is the production to obtain high purity SiC ceramics. In this study, we investigated roles of the sintering additives(Al2O3:Y2O3) to fabrication of the SiC ceramics. The effects of SiO2 contents and density properties of the SiC ceramics were also investigated. To investigate the effects of SiO2, Al2O3/Y2O3 composition were fixed and then SiO2 ratios were changed as several kinds, and to confirm the effects of sintering additives ratios (Al2O3:Y2O3) they were changed between 4:6 and 6:4 in x wt.%.

  8. Comparative studies of silicon photomultipliers and traditional vacuum photomultiplier tubes

    NASA Astrophysics Data System (ADS)

    Shi, Feng; Lü, Jun-Guang; Lu, Hong; Wang, Huan-Yu; Ma, Yu-Qian; Hu, Tao; Zhou, Li; Cai, Xiao; Sun, Li-Jun; Yu, Bo-Xiang; Fang, Jian; Xie, Yu-Guang; An, Zheng-Hua; Wang, Zhi-Gang; Gao, Min; Li, Xin-Qiao; Xu, Yan-Bing; Wang, Ping; Sun, Xi-Lei; Zhang, Ai-Wu; Xue, Zhen; Liu, Hong-Bang; Wang, Xiao-Dong; Zhao, Xiao-Yun; Zheng, Yang-Heng; Meng, Xiang-Cheng; Wang, Hui

    2011-01-01

    Silicon photomultipliers (SiPMs) are a new generation of semiconductor-based photon counting devices with the merits of low weight, low power consumption and low voltage operation, promising to meet the needs of space particle physics experiments. In this paper, comparative studies of SiPMs and traditional vacuum photomultiplier tubes (PMTs) have been performed regarding the basic properties of dark currents, dark counts and excess noise factors. The intrinsic optical crosstalk effect of SiPMs was evaluated.

  9. Comparative study of acceleration transducers for biomedical applications

    NASA Astrophysics Data System (ADS)

    Buchczik, Dariusz; Wyżgolik, Roman; Pietraszek, Stanisław

    2006-10-01

    The results of comparative studies of the metrological parameters of acceleration transducers constructed in Institute of Electronics, Silesian University of Technology is presented in this article. The construction of the transducers is based on commercially available monolithic accelerometers and optimized for biomedical applications. The parameters determined during the tests are similar to the parameters of the monolithic accelerometers declared by their manufacturers. It proofs that both the mechanical and the electronic construction of the transducers are correct.

  10. [Comparative study of two dried intradermal BCG vaccines (author's transl)].

    PubMed

    Fillastre, C; Guerin, N; Danusantoso, H; Sardadi, S

    1979-01-01

    Two BCG vaccines prepared from the same strain were studied clinically in Indonesia and in France. The concentration in culturable particles was comparable. Observed differences in the Mantoux results are discussed. The French results, based on use in a temperate climate by a specialized team, on well nourished children, appear better than the Indonesian findings. Further steps should be undertaken to improve results in Indonesia. PMID:539694

  11. A Comparative Study of Heat Transfer in Metallic Materials

    NASA Astrophysics Data System (ADS)

    Pǎucǎ, Adina; Hepuţ, Teodor; Pinca-Bretotean, Camelia; Stoica, Diana

    2011-09-01

    Rolling of metallic materials with heat transfer occurs as a result of interaction between the workpiece and the rolling cylinders incandescent. Heat transferred by diffusion into the cylinders generates variable temperature fields. These fields produce variable temperature thermal stress in each rotation cycle of rolling cylinders. This paper aims at mathematical modeling of variable temperature fields, using Matlab. These diagrams obtained are compared with those obtained following experimental study of the thermal lamination cylinders for 5 states isochronous temperature.

  12. A Comparative Study on Electronic versus Traditional Data Collection in a Special Education Setting

    ERIC Educational Resources Information Center

    Ruf, Hernan Dennis

    2012-01-01

    The purpose of the current study was to determine the efficiency of an electronic data collection method compared to a traditional paper-based method in the educational field, in terms of the accuracy of data collected and the time required to do it. In addition, data were collected to assess users' preference and system usability. The study…

  13. Using epidemiology to regulate food additives: saccharin case-control studies.

    PubMed

    Cordle, F; Miller, S A

    1984-01-01

    The increasing use of nonnutritive sweeteners and the widely publicized 1969 ban on cyclamate led to additional investigations in rodents of the carcinogenic potential of saccharin. Preliminary results of a long-term feeding study indicated formation of bladder tumors in rodents, and collective experimental evidence has demonstrated that high doses of the synthetic sweetener saccharin can cause bladder cancer in rodents. Based on the results of that and other rodent studies indicating an increased risk of bladder cancer associated with saccharin, the Commissioner of the Food and Drug Administration announced the agency's intention to propose a ban on saccharin. This intention was made known in April 1977 under the Delaney Clause of the Food, Drug, and Cosmetic Act. The clause essentially states that no additive shall be deemed safe if it is found to induce cancer in man or animals, or if it is found, after tests appropriate for the evaluation of the safety of food additives, to induce cancer in man or animals. Also in 1977, a group of epidemiologists began to assess the available epidemiologic information to determine the potential human risk. This report describes the assessment of several human epidemiologic studies available then and the results of more recent epidemiologic studies. PMID:6431484

  14. Comparative Study of Permeatal Sandwich Tympanoplasty and Postaural Underlay Technique

    PubMed Central

    Nagpure, Prakash Shankarrao; Yadav, Manish; Chavan, Sushil

    2016-01-01

    Introduction Tympanoplasty is the most common operation performed by an Otolaryngologist right from the period of residency. During the last hundred years various modifications in this surgical technique have come up because of continued efforts made by otologists all over the world to achieve the best surgical outcome. Aim To compare the graft take up and complications associated with the Permeatal Sandwich Tympanoplasty performed with the use of Otoendoscope and traditional Postaural Underlay technique of Tympanoplasty from 1st September 2014 to 30th August 2015. Materials and Methods Patients attending the ENT OPD, suffering from Chronic Suppurative Otitis Media (CSOM) were selected on the basis of type of perforation and their workup was done to assess the candidature for tympanoplasty. Results A total of 100 patients were included in the study and the overall graft take was 92.3% in cases of Permeatal Sandwich technique as compared to 64.58% in the case of postaural underlay technique, with a majority of the failures in the large central perforation group rendering a p = 0.021 for patients operated for Large perforations, p = 0.036 for moderate perforations and p = 0.476 for small perforations. The overall p = 0.000649 which is highly significant. On comparing the complications there were only 2 cases in Permeatal Sandwich Technique compared to 25 cases in Postaural Underlay technique rendering a highly significant p-value 0f 0.000000348. There was a difference in hearing improvement with majority of the cases improving to the range of 16-25 dB in Permeatal Sandwich technique compared to 26-45 dB in Postaural Underlay technique. Conclusion Permeatal Sandwich technique produce much better results when compared with Postaural approach in terms of graft take up, complications and hearing improvement. PMID:27190842

  15. Comparative Statistical Study of Some SAP UI Technologies

    NASA Astrophysics Data System (ADS)

    Berdie, Adela; Osaci, Mihaela; Dan Lemle, Ludovic

    2011-09-01

    The goal of this paper is to present a comparative study on some web UI (User Interface) technologies that involve the creation of web applications on the platform SAP Net Weaver AS 7.01 of the integrated SAP (System Application Products) system. The attention will be directed mainly to the ABAP (Advanced Business Application Programing) development environment and to the Web Dynpro (WD) technologies, Floor Plan Manager (FPM) and Web Client UI. Through this study, we make an assesment regarding the decision of choosing a technology for the realisation of a project which consists of a web application.

  16. Image based 3D city modeling : Comparative study

    NASA Astrophysics Data System (ADS)

    Singh, S. P.; Jain, K.; Mandla, V. R.

    2014-06-01

    3D city model is a digital representation of the Earth's surface and it's related objects such as building, tree, vegetation, and some manmade feature belonging to urban area. The demand of 3D city modeling is increasing rapidly for various engineering and non-engineering applications. Generally four main image based approaches were used for virtual 3D city models generation. In first approach, researchers were used Sketch based modeling, second method is Procedural grammar based modeling, third approach is Close range photogrammetry based modeling and fourth approach is mainly based on Computer Vision techniques. SketchUp, CityEngine, Photomodeler and Agisoft Photoscan are the main softwares to represent these approaches respectively. These softwares have different approaches & methods suitable for image based 3D city modeling. Literature study shows that till date, there is no complete such type of comparative study available to create complete 3D city model by using images. This paper gives a comparative assessment of these four image based 3D modeling approaches. This comparative study is mainly based on data acquisition methods, data processing techniques and output 3D model products. For this research work, study area is the campus of civil engineering department, Indian Institute of Technology, Roorkee (India). This 3D campus acts as a prototype for city. This study also explains various governing parameters, factors and work experiences. This research work also gives a brief introduction, strengths and weakness of these four image based techniques. Some personal comment is also given as what can do or what can't do from these softwares. At the last, this study shows; it concluded that, each and every software has some advantages and limitations. Choice of software depends on user requirements of 3D project. For normal visualization project, SketchUp software is a good option. For 3D documentation record, Photomodeler gives good result. For Large city

  17. A comparative study of fluoride release from two different sealants

    PubMed Central

    Ananda, Shimoga-Raju

    2014-01-01

    Objectives: The introduction of fluoride releasing sealants and glass ionomer cements as fissure sealants adds another dimension to prevention of pit and fissure caries. The ability of resin sealants and glass ionomer cements to release fluoride on a long term basis to the sealed enamel and the adjacent unsealed pit and fissure and cuspal incline enamel may allow for further reduction in pit and fissure caries experience for children. Hence, the study was conducted to compare the amount of fluoride release in the plaque after placing fluoride releasing pit and fissure sealants and glass ionomer fissure sealants used in Atraumatic Restorative Treatment (ART) approach. To compare the fluoride release of both the materials at the different time intervals. Material and Methods: A total of 60 school going children were included in this study. Before application of the sealants, baseline plaque fluoride levels were estimated from all the study subjects. After application of sealants again the same was estimated at an interval of 24 hour, 9 days, 2 weeks and 4 weeks. Results: The peak plaque fluoride levels were achieved at 24 hours after application of fissure sealants in all the groups. Conclusions: Within the limitation of the study, the present study indicated that fluoride releasing fissure sealants may act as a source of fluoride in plaque which will help in preventing pit and fissure and smooth surface caries in the tooth sealed with fissure sealants. Key words:Plaque fluoride, pit and fissures sealants, dental caries. PMID:25674315

  18. Study of asphalt/asphaltene precipitation during addition of solvents to West Sak crude

    SciTech Connect

    Jiang, J.C.; Patil, S.L.; Kamath, V.A. )

    1990-07-01

    In this study, experimental data on the amount of asphalt and asphaltene precipitation due to addition of solvents to West Sak crude were gathered. The first set of tests were conducted for two types of West Sak stock tank oils. Solvents used include: ethane, carbon dioxide, propane, n-butane, n-pentane, n-heptane, Prudhoe Bay natural gas (PBG) and natural gas liquids (NGL). Effect of solvent to oil dilution ratio on the amount of precipitation was studied. Alteration of crude oil composition due to asphalt precipitation was measured using gas-liquid chromatography. A second set of experiments were conducted to measure asphaltene precipitation due to addition of CO{sub 2} to live (recombined) West Sak crude.

  19. A Study of Aluminum Combustion in Solids, Powders, Foams, Additively-Manufactured Lattices, and Composites

    NASA Astrophysics Data System (ADS)

    Black, James; Trammell, Norman; Batteh, Jad; Curran, Nicholas; Rogers, John; Littrell, Donald

    2015-06-01

    This study examines the fireball characteristics, blast parameters, and combustion efficiency of explosively-shocked aluminum-based materials. The materials included structural and non-structural aluminum forms - such as solid cylinders, foams, additively-manufactured lattices, and powders - and some polytetrafluoroethylene-aluminum (PTFE-Al) composites. The materials were explosively dispersed in a small blast chamber, and the blast properties and products were measured with pressure transducers, thermocouples, slow and fast ultraviolet/visible spectrometers, and high-speed video.

  20. Spectra-temporal patterns underlying mental addition: an ERP and ERD/ERS study.

    PubMed

    Ku, Yixuan; Hong, Bo; Gao, Xiaorong; Gao, Shangkai

    2010-03-12

    Functional neuroimaging data have shown that mental calculation involves fronto-parietal areas that are composed of different subsystems shared with other cognitive functions such as working memory and language. Event-related potential (ERP) analysis has also indicated sequential information changes during the calculation process. However, little is known about the dynamic properties of oscillatory networks in this process. In the present study, we applied both ERP and event-related (de-)synchronization (ERS/ERD) analyses to EEG data recorded from normal human subjects performing tasks for sequential visual/auditory mental addition. Results in the study indicate that the late positive components (LPCs) can be decomposed into two separate parts. The earlier element LPC1 (around 360ms) reflects the computing attribute and is more prominent in calculation tasks. The later element LPC2 (around 590ms) indicates an effect of number size and appears larger only in a more complex 2-digit addition task. The theta ERS and alpha ERD show modality-independent frontal and parietal differential patterns between the mental addition and control groups, and discrepancies are noted in the beta ERD between the 2-digit and 1-digit mental addition groups. The 2-digit addition (both visual and auditory) results in similar beta ERD patterns to the auditory control, which may indicate a reliance on auditory-related resources in mental arithmetic, especially with increasing task difficulty. These results coincide with the theory of simple calculation relying on the visuospatial process and complex calculation depending on the phonological process. PMID:20105450

  1. A comparative study of bifidobacteria in human babies and adults

    PubMed Central

    KHONSARI, Shadi; SUGANTHY, Mayuran; BURCZYNSKA, Beata; DANG, Vu; CHOUDHURY, Manika; PACHENARI, Azra

    2015-01-01

    The composition and diversity of the gut microbiota are known to be different between babies and adults. The aim of this project was to compare the level of bifidobacteria between babies and adults and to investigate the influence of lifestyle factors on the level of this bacterium in the gut. During this study, the levels of bifidobacteria in 10 human babies below 2 years of age were compared with that of 10 human adults above 40 years. The level of bifidobacteria proved to be significantly higher in babies in comparison with adults. This investigation concluded that a combination of several factors, such as age, diet, and BMI, has an important effect on the level of bifidobacteria in adults, while in babies, a combination of diet and age may influence the level of intestinal bifidobacteria. PMID:27200263

  2. Comparative studies of industrial grade carbon black powders

    NASA Astrophysics Data System (ADS)

    Chawla, Komal; Chauhan, Alok P. S.

    2016-05-01

    Comparative studies of two dissimilar industrial grade Carbon Black (CB) powders (N375 and N405) were conducted. The structure, surface area and particle size are the three important characteristics of CB powder that determine their processability and application as filler in preparing rubber compounds. The powders were characterized for their structure using dibutyl phthalate absorption (DBPA), particle size via laser particle size analyzer and surface area by nitrogen adsorption method. The structural characterization showed that N405 had lower DBPA in comparison to N375, confirming low structure of N405 grade CB powder. It was observed from the particle size analysis that N375 was coarser than N405 grade CB. The total surface area values were determined by the BET method based on the cross sectional area of the nitrogen molecule. N375, a coarse grade CB powder with high structure, depicted less surface area as compared to N405.

  3. A comparative study of bifidobacteria in human babies and adults.

    PubMed

    Khonsari, Shadi; Suganthy, Mayuran; Burczynska, Beata; Dang, Vu; Choudhury, Manika; Pachenari, Azra

    2016-01-01

    The composition and diversity of the gut microbiota are known to be different between babies and adults. The aim of this project was to compare the level of bifidobacteria between babies and adults and to investigate the influence of lifestyle factors on the level of this bacterium in the gut. During this study, the levels of bifidobacteria in 10 human babies below 2 years of age were compared with that of 10 human adults above 40 years. The level of bifidobacteria proved to be significantly higher in babies in comparison with adults. This investigation concluded that a combination of several factors, such as age, diet, and BMI, has an important effect on the level of bifidobacteria in adults, while in babies, a combination of diet and age may influence the level of intestinal bifidobacteria. PMID:27200263

  4. Mineral resources of the Buffalo Hump and Sand Dunes Addition Wilderness Study Areas, Sweetwater County, Wyoming

    SciTech Connect

    Gibbons, A.B.; Barbon, H.N.; Kulik, D.M. ); McDonnell, J.R. Jr. )

    1990-01-01

    The authors present a study to assess the potential for undiscovered mineral resources and appraise the identified resources of the Buffalo Hump and Sand Dunes Addition Wilderness Study Areas, southwestern Wyoming, There are no mines, prospects, or mineralized areas nor any producing oil or gas wells; however, there are occurrences of coal, claystone and shale, and sand. There is a moderate resource potential for oil shale and natural gas and a low resource potential for oil, for metals, including uranium, and for geothermal sources.

  5. A Comparative Study on Emerging Electric Vehicle Technology Assessments

    SciTech Connect

    Ford, Jonathan; Khowailed, Gannate; Blackburn, Julia; Sikes, Karen

    2011-03-01

    Numerous organizations have published reports in recent years that investigate the ever changing world of electric vehicle (EV) technologies and their potential effects on society. Specifically, projections have been made on greenhouse gas (GHG) emissions associated with these vehicles and how they compare to conventional vehicles or hybrid electric vehicles (HEVs). Similar projections have been made on the volumes of oil that these vehicles can displace by consuming large amounts of grid electricity instead of petroleum-based fuels. Finally, the projected rate that these new vehicle fleets will enter the market varies significantly among organizations. New ideas, technologies, and possibilities are introduced often, and projected values are likely to be refined as industry announcements continue to be made. As a result, over time, a multitude of projections for GHG emissions, oil displacement, and market penetration associated with various EV technologies has resulted in a wide range of possible future outcomes. This leaves the reader with two key questions: (1) Why does such a collective range in projected values exist in these reports? (2) What assumptions have the greatest impact on the outcomes presented in these reports? Since it is impractical for an average reader to review and interpret all the various vehicle technology reports published to date, Sentech Inc. and the Oak Ridge National Laboratory have conducted a comparative study to make these interpretations. The primary objective of this comparative study is to present a snapshot of all major projections made on GHG emissions, oil displacement, or market penetration rates of EV technologies. From the extensive data found in relevant publications, the key assumptions that drive each report's analysis are identified and 'apples-to-apples' comparisons between all major report conclusions are attempted. The general approach that was taken in this comparative study is comprised of six primary steps: (1

  6. Additional Treatment Services in a Cocaine Treatment Study: Level of Services Obtained and Impact on Outcome

    PubMed Central

    Worley, Matthew; Gallop, Robert; Gibbons, Mary Beth Connolly; Ring-Kurtz, Sarah; Present, Julie; Weiss, Roger D.; Crits-Christoph, Paul

    2009-01-01

    The objective of this study was to examine the level of additional treatment services obtained by patients enrolled in the NIDA Cocaine Collaborative Study, a multi-center efficacy trial of four treatments for cocaine dependence, and to determine whether these services impact treatment outcome. Cocaine-dependent patients (N = 487) were recruited at five sites and randomly assigned to six months of one of four psychosocial treatments. Assessments were made at baseline, monthly during treatment, and at follow-ups at 9, 12, 15, and 18 months post-randomization. On average, patients received little or no additional treatment services during active treatment (first 6 months), but the rate of obtaining most services increased during the follow-up phase (month 7 to 18). In general, the treatment groups did not differ in the rates of obtaining non-protocol services. For all treatment groups, patients with greater psychiatric severity received more medical and psychiatric services during active treatment and follow-up. Use of treatment services was unrelated to drug use outcomes during active treatment. However, during the follow-up period, increased use of psychiatric medication, 12-step attendance, and 12-step participation was related to less drug use. The results suggest that during uncontrolled follow-up phases, additional non-protocol services may potentially confound the interpretation of treatment group comparisons in drug use outcomes. PMID:18463998

  7. Comparative study of clinical pulmonary surfactants using atomic force microscopy

    PubMed Central

    Zhang, Hong; Fan, Qihui; Wang, Yi E.; Neal, Charles R.; Zuo, Yi Y.

    2016-01-01

    Clinical pulmonary surfactant is routinely used to treat premature newborns with respiratory distress syndrome, and has shown great potential in alleviating a number of neonatal and adult respiratory diseases. Despite extensive study of chemical composition, surface activity, and clinical performance of various surfactant preparations, a direct comparison of surfactant films is still lacking. In this study, we use atomic force microscopy to characterize and compare four animal-derived clinical surfactants currently used throughout the world, i.e., Survanta, Curosurf, Infasurf and BLES. These modified-natural surfactants are further compared to dipalmitoyl phosphatidylcholine (DPPC), a synthetic model surfactant of DPPC:palmitoyl-oleoyl phosphatidylglycerol (POPG) (7:3), and endogenous bovine natural surfactant. Atomic force microscopy reveals significant differences in the lateral structure and molecular organization of these surfactant preparations. These differences are discussed in terms of DPPC and cholesterol contents. We conclude that all animal-derived clinical surfactants assume a similar structure of multilayers of fluid phospholipids closely attached to an interfacial monolayer enriched in DPPC, at physiologically relevant surface pressures. This study provides the first comprehensive survey of the lateral structure of clinical surfactants at various surface pressures. It may have clinical implications on future application and development of surfactant preparations. PMID:21439262

  8. Spiritual coping in rehabilitation- a comparative study: part 2.

    PubMed

    Baldacchino, Donia; Torskenaes, Kristina; Kalfoss, Mary; Borg, Josette; Tonna, Aaron; Debattista, Clifford; Decelis, Neville; Mifsud, Rodianne

    Spiritual coping, which may or may not contain religiosity, may enhance adaptation of clients with chronic illness. Part 1 of this article (Baldacchino et al, 2013) presented the research methodology of this cross-sectional comparative study, which explored the spiritual coping of clients with chronic illness receiving rehabilitation services in Malta (n=44) (lower limb amputation: n=10, chronic heart disease: n=9, osteoarthritis in an institution: n=10 and in the community: n=15) and Norway (n=16) (post-hip/shoulder surgery: n=5; chronic heart disease: n=5; chronic pain: n=6). Data were collected from seven purposive samples by focus groups. Roy's adaptation model (1984) and Neuman's Systems Model (2010) guided the study. Part2 discusses the findings, which consist of one main spiritual coping theme and three sub-themes: 'adopting religious coping strategies, relationship with God, and time for reflection and counting one's blessings'. Commonalities were found in the findings except in one dimension, which was found only in the Malta group, that is, being supported by others with a similar condition. This difference may be a result of the environment in the rehabilitation centres, cultural, and geographical differences between the two countries. While considering the limitations of this study, recommendations are proposed to the rehabilitation and education sectors and further trans-cultural comparative longitudinal research with mixed method approach on various clients with acute, chronic and life-threatening illness. PMID:23588017

  9. Discourse Formation in Comparative Education. 4th, Revised Edition. Comparative Studies Series. Volume 10

    ERIC Educational Resources Information Center

    Schriewer, Jurgen, Ed.

    2012-01-01

    New theories and theory-based methodological approaches have found their way into Comparative Education--just as into Comparative Social Science more generally--in increasing number in the recent past. The essays of this volume express and critically discuss quite a range of these positions such as, inter alia, the theory of self-organizing social…

  10. Comparative study of minutiae selection algorithms for ISO fingerprint templates

    NASA Astrophysics Data System (ADS)

    Vibert, B.; Charrier, C.; Le Bars, J.-M.; Rosenberger, C.

    2015-03-01

    We address the selection of fingerprint minutiae given a fingerprint ISO template. Minutiae selection plays a very important role when a secure element (i.e. a smart-card) is used. Because of the limited capability of computation and memory, the number of minutiae of a stored reference in the secure element is limited. We propose in this paper a comparative study of 6 minutiae selection methods including 2 methods from the literature and 1 like reference (No Selection). Experimental results on 3 fingerprint databases from the Fingerprint Verification Competition show their relative efficiency in terms of performance and computation time.

  11. Comparative DFT study of crystalline ammonium perchlorate and ammonium dinitramide.

    PubMed

    Zhu, Weihua; Wei, Tao; Zhu, Wei; Xiao, Heming

    2008-05-22

    The electronic structure, vibrational properties, absorption spectra, and thermodynamic properties of crystalline ammonium perchlorate (AP) and ammonium dinitramide (ADN) have been comparatively studied using density functional theory in the local density approximation. The results shows that the p states for the two solids play a very important role in their chemical reaction. From the low frequency to high frequency region, ADN has more motion modes for the vibrational frequencies than AP. The absorption spectra of AP and ADN display a few, strong bands in the fundamental absorption region. The thermodynamic properties show that ADN is easier to decompose than AP as the temperature increases. PMID:18396853

  12. A comparative study of feature-salience ranking techniques.

    PubMed

    Wang, W; Jones, P; Partridge, D

    2001-07-01

    We assess the relative merits of a number of techniques designed to determine the relative salience of the elements of a feature set with respect to their ability to predict a category outcome-for example, which features of a character contribute most to accurate character recognition. A number of different neural-net-based techniques have been proposed (by us and others) in addition to a standard statistical technique, and we add a technique based on inductively generated decision trees. The salience of the features that compose a proposed set is an important problem to solve efficiently and effectively, not only for neural computing technology but also in order to provide a sound basis for any attempt to design an optimal computational system. The focus of this study is the efficiency and the effectiveness with which high-salience subsets of features can be identified in the context of ill-understood and potentially noisy real-world data. Our two simple approaches, weight clamping using a neural network and feature ranking using a decision tree, generally provide a good, consistent ordering of features. In addition, linear correlation often works well. PMID:11440599

  13. Comparative cytogenetic study of three Macrolophus species (Heteroptera, Miridae)

    PubMed Central

    Jauset, Ana Maria; Edo-Tena, Eva; Castañé, Cristina; Agustí, Nuria; Alomar, Oscar; Grozeva, Snejana

    2015-01-01

    Abstract Macrolophus pygmaeus (Rambur, 1839) (Insecta, Heteroptera, Miridae) is a predator of key vegetable crop pests applied as a biocontrol agent in the Mediterranean region. Macrolophus pygmaeus and Macrolophus melanotoma (A. Costa, 1853) are cryptic species with great morphological similarity which results in their misidentification and negative consequences for the conservation of their populations on greenhouse and outdoor crops. In order to find out specific markers for their separation we studied the karyotype, male meiosis and heterochromatin composition of these species and additionally of a third species (as a reference one), Macrolophus costalis Fieber, 1858. We demonstrate here that all the three species share achiasmate male meiosis and sex chromosome pre-reduction. On the other hand, the species differ in karyotype, with 2n=28 (26+XY) in Macrolophus pygmaeus, 2n=27 (24+X1X2Y) in Macrolophus costalis, and 2n=34 (32+XY) in Macrolophus melanotoma, and heterochromatin distribution and composition. In addition, the species differ in sperm morphology: sperm cells of Macrolophus costalis are significantly longer with longer head and tail than those of Macrolophus melanotoma and Macrolophus pygmaeus, whereas sperm cells of Macrolophus melanotoma have a longer tail than those of Macrolophus pygmaeus. All these characters can be used as markers to identify the species, in particular the cryptic species Macrolophus melanotoma and Macrolophus pygmaeus. PMID:26753078

  14. Strategic Petroleum Reserve (SPR) additional geologic site characterization studies, Bryan Mound Salt Dome, Texas

    SciTech Connect

    Neal, J.T.; Magorian, T.R.; Ahmad, S.

    1994-11-01

    This report revises the original report that was published in 1980. Some of the topics covered in the earlier report were provisional and it is now practicable to reexamine them using new or revised geotechnical data and that obtained from SPR cavern operations, which involves 16 new caverns. Revised structure maps and sections show interpretative differences as compared with the 1980 report and more definition in the dome shape and caprock structural contours, especially a major southeast-northwest trending anomalous zone. The original interpretation was of westward tilt of the dome, this revision shows a tilt to the southeast, consistent with other gravity and seismic data. This interpretation refines the evaluation of additional cavern space, by adding more salt buffer and allowing several more caverns. Additional storage space is constrained on this nearly full dome because of low-lying peripheral wetlands, but 60 MMBBL or more of additional volume could be gained in six or more new caverns. Subsidence values at Bryan Mound are among the lowest in the SPR system, averaging about 11 mm/yr (0.4 in/yr), but measurement and interpretation issues persist, as observed values are about the same as survey measurement accuracy. Periodic flooding is a continuing threat because of the coastal proximity and because peripheral portions of the site are at elevations less than 15 ft. This threat may increase slightly as future subsidence lowers the surface, but the amount is apt to be small. Caprock integrity may be affected by structural features, especially the faulting associated with anomalous zones. Injection wells have not been used extensively at Bryan Mound, but could be a practicable solution to future brine disposal needs. Environmental issues center on the areas of low elevation that are below 15 feet above mean sea level: the coastal proximity and lowland environment combined with the potential for flooding create conditions that require continuing surveillance.

  15. A Comparative Study of Super-Earth Atmospheres

    NASA Astrophysics Data System (ADS)

    Dragomir, Diana; Benneke, Bjoern; Crossfield, Ian; Howard, Andrew; Knutson, Heather

    2014-12-01

    Ongoing transit surveys such as Kepler have resulted in the discovery of more than a dozen super?Earth planets with measured masses and radii. These planets are challenging targets for atmospheric characterization studies, and to date only one (GJ 1214b) has been studied in detail. In this proposal we focus on three additional super-Earths that are amenable to transmission spectroscopy studies due to their bright host stars (HD 97658b and 55 Cnc e) or their exceptionally low density (Kepler-138d). Our Spitzer measurements of these planets' transit depths will complement our already approved HST observations and contribute to distinguishing between clear hydrogen?dominated atmospheres and compact high-metallicity atmospheres, as well as constraining the composition of any high-altitude clouds. We will also search for evidence of carbon-bearing molecules, in particular for 55 Cnc e, a planet for which a carbon-rich composition has been suggested. Our observations will probe the poorly understood transition region between gas giant planets and terrestrial worlds, and provide constraints on the formation regions of these super-Earths. The results of this program will inform the direction to be taken by large-scale studies of these worlds with JWST.

  16. Comparative Studies on Plastoquinones. IV. Plastoquinones in Algae

    PubMed Central

    Sun, Elena; Barr, Rita; Crane, F. L.

    1968-01-01

    Plastoquinones A and C have been found in all classes of algae, including representatives of greens, yellow-greens, blue-greens, reds, browns and the flagellate, Euglena. Plastoquinone C from red and brown algae can be separated into 6 different types. An additional plastoquinone C has been found in Gigartina and Rhydomela. From chromatographic evidence this may be equivalent to plastoquinone Co, a C type with a hydroxyl group on the first isoprene unit of the terpenoid sidechain of this substituted benzo-quinone. The ubiquinone, vitamin K and α-tocopherylquinone content of several algae is also reported. The presence of plastoquinone A in all green plants and many algae indicates that it may be a functional element in photosynthesis. Our study shows that plastoquinone C is more regularly present in algae than has been previously shown. PMID:16656993

  17. [Comparative study on trace elements in benefit traditional Chinese medicines].

    PubMed

    Fan, Wen-Xiu

    2007-07-01

    The contents of trace elements Zn, Cu, Mn and Fe in 20 kinds of benefit traditional Chinese medicines were determined by FAAS. The recovery rates obtained by standard addition method is between 96.8% and 104.3%, and the RSD is lower than 2.0%. The results of the determination show that benefit traditional Chinese medicines are rich in trace elements such as Zn, Cu, Mn and Fe. Hematonic has the highest content of Fe. The content of Zn, Mn and Fe is relatively high in Qi-invigorating drugs. The content of Zn and Mn is relatively high in maletonic, while Yin-nourishing drugs have lower content of Fe. The results will provide scientific data for the study on the elements in benefit traditional Chinese medicines and on their relativity of efficacy of medicine. PMID:17944431

  18. Comparative study of Waste Isolation Pilot Plant (WIPP) transportation alternatives

    SciTech Connect

    Not Available

    1994-02-01

    WIPP transportation studies in the Final Supplement Environmental Impact Statement for WIPP are the baseline for this report. In an attempt to present the most current analysis, this study incorporates the most relevant data available. The following three transportation options are evaluated for the Disposal Phase, which is assumed to be 20 years: Truck shipments, consisting of a tractor and trailer, with three TRUPACT-IIs or one RH-72B; Regular commercial train shipments consisting of up to three railcars carrying up to 18 TRUPACT-IIs or up to six RH-72Bs; Dedicated train shipments consisting of a locomotive, an idle car, railcars carrying 18 TRUPACT-IIs or six RH-72Bs, another idle car, and a caboose or passenger car with an emergency response specialist. No other cargo is carried. This report includes: A consideration of occupational and public risks and exposures, and other environmental impacts; A consideration of emergency response capabilities; and An extimation of comparative costs.

  19. Visual Encodings of Temporal Uncertainty: A Comparative User Study.

    PubMed

    Gschwandtnei, Theresia; Bögl, Markus; Federico, Paolo; Miksch, Silvia

    2016-01-01

    A number of studies have investigated different ways of visualizing uncertainty. However, in the temporal dimension, it is still an open question how to best represent uncertainty, since the special characteristics of time require special visual encodings and may provoke different interpretations. Thus, we have conducted a comprehensive study comparing alternative visual encodings of intervals with uncertain start and end times: gradient plots, violin plots, accumulated probability plots, error bars, centered error bars, and ambiguation. Our results reveal significant differences in error rates and completion time for these different visualization types and different tasks. We recommend using ambiguation - using a lighter color value to represent uncertain regions - or error bars for judging durations and temporal bounds, and gradient plots - using fading color or transparency - for judging probability values. PMID:26529717

  20. A Comparative Study of Different Deblurring Methods Using Filters

    NASA Astrophysics Data System (ADS)

    Srimani, P. K.; Kavitha, S.

    2011-12-01

    This paper attempts to undertake the study of Restored Gaussian Blurred Images by using four types of techniques of deblurring image viz., Wiener filter, Regularized filter, Lucy Richardson deconvolution algorithm and Blind deconvolution algorithm with an information of the Point Spread Function (PSF) corrupted blurred image. The same is applied to the scanned image of seven months baby in the womb and they are compared with one another, so as to choose the best technique for restored or deblurring image. This paper also attempts to undertake the study of restored blurred image using Regualr Filter(RF) with no information about the Point Spread Function (PSF) by using the same four techniques after executing the guess of the PSF. The number of iterations and the weight threshold of it to choose the best guesses for restored or deblurring image of these techniques are determined.

  1. Teenage pregnancy: a comparative study of the outcome and complications.

    PubMed

    Thekkekkara, Tina; Veenu, J

    2009-01-01

    This study compares the outcome and complications of pregnancy among teenagers with those above 19 years of age. This retrospective study conducted in a maternity hospital in rural Karnataka, under the guidance of the department of community medicine, St Johns National Academy of Health Sciences, Bangalore, included 221 women who delivered between February 2003 and April 2003. The data was tabulated in excel spreadsheet and analysed using epi 6 programme. Anaemia among teenage multigravidae was found to be a significant health problem. There were no statistically significant differences between the gestational age at delivery and the mode of delivery in the different age groups. Teenage pregnancy was not found to be associated with an increased risk for antenatal complications or postnatal complications. There was no increased incidence of low birth weight or congenital anomalies among the babies of teenage mothers. Mortality was not found to be increased both among the teenage mothers as well as their babies. PMID:19588686

  2. Professional navigation: a comparative study of two Canadian models.

    PubMed

    Fillion, Lise; Cook, Sandra; Veillette, Anne-Marie; de Serres, Marie; Aubin, Michèle; Rainville, François; Fitch, Margaret; Doll, Richard

    2012-01-01

    For many cancer control programs, cancer navigation has emerged as a specific strategy to improve access to supportive care and the patients' experience of cancer care. This study contributes to a better understanding of professional navigation by comparing two Canadian models: Quebec's Pivot Nurse in Oncology (PNO) and Nova Scotia's Cancer Patient Navigator (CPN). Qualitative interviews were conducted with professional navigators, patients and family members, front-line staff, physicians and health administrators (interviews: n = 49; focus groups: n = 10). The two models were analyzed using the professional navigation framework (Fillion et al., 2012). Although the models are different, results show that professional navigators in both programs perform similar functions and face similar challenges. This study highlights the complexity and the value of cancer navigation and recommends relevant actions to optimize its management within the health care system. PMID:23362659

  3. A Comparative Study on Automotive Brake Testing Standards

    NASA Astrophysics Data System (ADS)

    Kumbhar, Bhau Kashinath; Patil, Satyajit Ramchandra; Sawant, Suresh Maruti

    2016-06-01

    Performance testing of automotive brakes involves determination of stopping time, distance and deceleration level. Braking performance of an automobile is required to be ensured for various surfaces like dry, wet, concrete, bitumen etc. as well as for prolonged applications. Various brake testing standards are used worldwide to assure vehicle and pedestrian safety. This article presents methodologies used for automotive service brake testing for two wheelers. The main contribution of this work lies in comparative study of three main brake testing standards; viz. Indian Standards, Federal Motor Vehicle Safety Standards and European Economic Commission Standards. This study shall help the policy makers to choose the best criteria out of these three while formulating newer edition of testing standards.

  4. A numerical study of the influence of ammonia addition on the auto-ignition limits of methane/air mixtures.

    PubMed

    Van den Schoor, F; Norman, F; Vandebroek, L; Verplaetsen, F; Berghmans, J

    2009-05-30

    In this study the auto-ignition limit of ammonia/methane/air mixtures is calculated based upon a perfectly stirred reactor model with convective heat transfer. The results of four different reaction mechanisms are compared with existing experimental data at an initial temperature of 723 K with ammonia concentrations of 0-20 mol.% and methane concentrations of 2.5-10 mol.%. It is found that the calculation of the auto-ignition limit pressure at constant temperature leads to larger relative deviations between calculated and experimental results than the calculation of the auto-ignition temperature at constant pressure. In addition to the calculations, a reaction path analysis is performed to explain the observed lowering of the auto-ignition limit of methane/air mixtures by ammonia addition. It is found that this decrease is caused by the formation of NO and NO(2), which enhance the oxidation of methane at low temperatures. PMID:18926632

  5. Metabolic syndrome in patients with psoriasis: A comparative study

    PubMed Central

    Lakshmi, Sristi; Nath, Amiya Kumar; Udayashankar, Carounanidy

    2014-01-01

    Background: Psoriasis patients are at increased risk of developing the metabolic syndrome (MS). Proinflammatory cytokines such as tumor necrosis factor-α, interleukin-6 that are increased in the psoriatic plaques are known to contribute to features of MS such as hypertension, dyslipidemia and insulin resistance. Aims: (1) To establish the frequency of MS in patients with psoriasis. (2) To study the risk factors associated with MS in psoriasis. Materials and Methods: A hospital based comparative study was conducted involving 40 adult patients with psoriasis and 40 age- and sex-matched controls. All participants were evaluated for components of MS. Results: Both groups included 31 males and 9 females. The mean age of the cases and controls were 49.95 years and 49.35 years, respectively. Psoriasis patients with MS had a statistically significant higher mean age (56.31 ± 11.36 years) compared with those without MS (46.89 ± 11.51 years). MS was present in 13 out of 40 (32.5%) patients with psoriasis and 12 out of 40 (30%) controls; this difference was not statistically significant. Higher age and female gender correlated with the presence of MS in psoriasis patients. The presence of MS in psoriasis patients was statistically independent of psoriasis area severity index score, body surface area involvement or psoriatic arthropathy. Conclusion: Our results suggest that there is no close correlation between psoriasis and MS in South Indian patients. PMID:24860744

  6. A comparative Study of Circulation Patterns at Active Lava Lakes

    NASA Astrophysics Data System (ADS)

    Lev, Einat; Oppenheimer, Clive; Spampinato, Letizia; Hernandez, Pedro; Unglert, Kathi

    2016-04-01

    Lava lakes present a rare opportunity to study magma dynamics in a large scaled-up "crucible" and provide a unique natural laboratory to ground-truth dynamic models of magma circulation. The persistence of lava lakes allows for long-term observations of flow dynamics and of lava properties, especially compared to surface lava flows. There are currently five persistent lava lakes in the world: Halemaumau in Kilauea (Hawaii, USA), Erta Ale (Ethiopia), Nyiragongo (Congo), Erebus (Antarctica), and Villarica (Chile). Marum and Benbow craters of Ambrym volcano (Vanuatu) and Masaya (Nicaragua) have often hosted lava lakes as well. We use visible-light and thermal infrared time-lapse and video footage collected at all above lakes (except Villarica, where the lake is difficult to observe), and compare the circulation patterns recorded. We calculate lake surface motion from the footage using the optical flow method (Lev et al., 2012) to produce 2D velocity fields. We mined both the surface temperature field and the surface velocity field for patterns using machine learning techniques such as "self-organizing maps (SOMs)" and "principle component analysis (PCA)". We use automatic detection technique to study the configuration of crustal plates at the lakes' surface. We find striking differences among the lakes, in flow direction, flow speed, frequency of changes in flow direction and speed, location and consistency of upwelling and downwelling, and crustal plate configuration. We relate the differences to lake size, shallow conduit geometry, lava viscosity, crystal and gas content, and crust integrity.

  7. Prevalence of Lebanese stroke survivors: A comparative pilot study.

    PubMed

    Lahoud, Nathalie; Salameh, Pascale; Saleh, Nadine; Hosseini, Hassan

    2016-09-01

    Stroke is a leading cause of morbidity and mortality worldwide and its late burden has mainly been attributable to developing countries. Lebanon is one of these countries where epidemiological studies on stroke burden are scarce but necessary. Thus, the present study was conducted to assess the prevalence of stroke survivors among Lebanese inhabitants. A cross-sectional survey was carried out using randomly selected landline phone numbers on all governorates to retrieve data on stroke survivors and their sociodemographic characteristics. Results were then standardized over the Lebanese and the World Health Organization (WHO) world populations. A total of 6963 Lebanese inhabitants were included in the study; among these were 56 stroke survivors. This led to an adjusted stroke prevalence of 0.50% [95% confidence interval (CI)=0.33-0.66%] and a world-standardized prevalence of 0.60% (95% CI=0.42-0.78%). A significantly higher stroke prevalence was found among older age groups and more socioeconomically privileged areas. Overall, the study showed a relatively higher prevalence of stroke in this sample of Lebanese inhabitants when compared to other developing countries. However, larger community-based studies with a clinical assessment of stroke cases are needed to confirm our findings. PMID:26599284

  8. Comparative study on the biodegradability of morpholinium herbicidal ionic liquids.

    PubMed

    Ławniczak, Łukasz; Materna, Katarzyna; Framski, Grzegorz; Szulc, Alicja; Syguda, Anna

    2015-07-01

    This study focused on evaluating the toxicity as well as primary and ultimate biodegradability of morpholinium herbicidal ionic liquids (HILs), which incorporated MCPA, MCPP, 2,4-D or Dicamba anions. The studied HILs were also subjected to determination of surface active properties in order to assess their influence on toxicity and biodegradability. The study was carried out with microbiota isolated from different environmental niches: sediments from river channel, garden soil, drainage trench collecting agricultural runoff stream, agricultural soil and municipal waste repository. The obtained results revealed that resistance to toxicity and biodegradation efficiency of the microbiota increased in the following order: microbiota from the waste repository > microbiota from agricultural soil ≈ microbiota from an agricultural runoff stream > microbiota from garden soil > microbiota from the river sludge. It was observed that the toxicity of HILs increased with the hydrophobicity of the cation, however the influence of the anion was more notable. The highest toxicity was observed when MCPA was used as the anion (EC50 values ranging from 60 to 190 mg L(-1)). The results of ultimate biodegradation tests indicated that only HILs with 2,4-D as the anion were mineralized to some extent, with slightly higher values for HILs with the 4-decyl-4-ethylmorpholinium cation (10-31 %) compared to HILs with the 4,4-didecylmorpholinium cation (9-20 %). Overall, the cations were more susceptible (41-94 %) to primary biodegradation compared to anions (0-61 %). The obtained results suggested that the surface active properties of the studied HILs may influence their toxicity and biodegradability by bacteria in different environmental niches. PMID:26099357

  9. Comparative Study of Algorithms for Automated Generalization of Linear Objects

    NASA Astrophysics Data System (ADS)

    Azimjon, S.; Gupta, P. K.; Sukhmani, R. S. G. S.

    2014-11-01

    Automated generalization, rooted from conventional cartography, has become an increasing concern in both geographic information system (GIS) and mapping fields. All geographic phenomenon and the processes are bound to the scale, as it is impossible for human being to observe the Earth and the processes in it without decreasing its scale. To get optimal results, cartographers and map-making agencies develop set of rules and constraints, however these rules are under consideration and topic for many researches up until recent days. Reducing map generating time and giving objectivity is possible by developing automated map generalization algorithms (McMaster and Shea, 1988). Modification of the scale traditionally is a manual process, which requires knowledge of the expert cartographer, and it depends on the experience of the user, which makes the process very subjective as every user may generate different map with same requirements. However, automating generalization based on the cartographic rules and constrains can give consistent result. Also, developing automated system for map generation is the demand of this rapid changing world. The research that we have conveyed considers only generalization of the roads, as it is one of the indispensable parts of a map. Dehradun city, Uttarakhand state of India was selected as a study area. The study carried out comparative study of the generalization software sets, operations and algorithms available currently, also considers advantages and drawbacks of the existing software used worldwide. Research concludes with the development of road network generalization tool and with the final generalized road map of the study area, which explores the use of open source python programming language and attempts to compare different road network generalization algorithms. Thus, the paper discusses the alternative solutions for automated generalization of linear objects using GIS-technologies. Research made on automated of road network

  10. Comparative study of visual pathways in owls (Aves: Strigiformes).

    PubMed

    Gutiérrez-Ibáñez, Cristián; Iwaniuk, Andrew N; Lisney, Thomas J; Wylie, Douglas R

    2013-01-01

    Although they are usually regarded as nocturnal, owls exhibit a wide range of activity patterns, from strictly nocturnal, to crepuscular or cathemeral, to diurnal. Several studies have shown that these differences in the activity pattern are reflected in differences in eye morphology and retinal organization. Despite the evidence that differences in activity pattern among owl species are reflected in the peripheral visual system, there has been no attempt to correlate these differences with changes in the visual regions in the brain. In this study, we compare the relative size of nuclei in the main visual pathways in nine species of owl that exhibit a wide range of activity patterns. We found marked differences in the relative size of all visual structures among the species studied, both in the tectofugal and the thalamofugal pathway, as well in other retinorecipient nuclei, including the nucleus lentiformis mesencephali, the nucleus of the basal optic root and the nucleus geniculatus lateralis, pars ventralis. We show that the barn owl (Tyto alba), a species widely used in the study of the integration of visual and auditory processing, has reduced visual pathways compared to strigid owls. Our results also suggest there could be a trade-off between the relative size of visual pathways and auditory pathways, similar to that reported in mammals. Finally, our results show that although there is no relationship between activity pattern and the relative size of either the tectofugal or the thalamofugal pathway, there is a positive correlation between the relative size of both visual pathways and the relative number of cells in the retinal ganglion layer. PMID:23296024

  11. A synchrotron study of microstructure gradient in laser additively formed epitaxial Ni-based superalloy

    DOE PAGESBeta

    Xue, Jiawei; Zhang, Anfeng; Li, Yao; Qian, Dan; Wan, Jingchun; Qi, Baolu; Tamura, Nobumichi; Song, Zhongxiao; Chen, Kai

    2015-10-08

    Laser additive forming is considered to be one of the promising techniques to repair single crystal Ni-based superalloy parts to extend their life and reduce the cost. Preservation of the single crystalline nature and prevention of thermal mechanical failure are two of the most essential issues for the application of this technique. Here we employ synchrotron X-ray microdiffraction to evaluate the quality in terms of crystal orientation and defect distribution of a Ni-based superalloy DZ125L directly formed by a laser additive process rooted from a single crystalline substrate of the same material. We show that a disorientation gradient caused bymore » a high density of geometrically necessary dislocations and resultant subgrains exists in the interfacial region between the epitaxial and stray grains. This creates a potential relationship of stray grain formation and defect accumulation. In conclusion, the observation offers new directions on the study of performance control and reliability of the laser additive manufactured superalloys.« less

  12. Isomeric Selective Studies of the Dominant Addition Channel in OH Initiated Oxidation of Isoprene

    NASA Astrophysics Data System (ADS)

    Ghosh, B.; Bugarin, A.; Connell, B.; North, S. W.

    2009-12-01

    We report the first isomeric selective study of the dominant isomeric pathway in the OH initiated oxidation of isoprene in the presence of O2 and NO using the Laser Photolysis-Laser Induced Fluorescence (LP-LIF) technique. The photolysis of monodeuterated/non deuterated 2-iodo-2-methyl-but-3-en-1-ol results exclusively in the dominant OH-isoprene addition product, providing important insight into the oxidation mechanism. Based on kinetic analysis of OH cycling experiments we have determined the rate constant for O2 addition to the hydroxy alkyl radical to be (1.0±0.5) × 10^(-12) cm^(3) s^(-1) and we find a value of (8.05±2.3) × 10^(-12) cm^(3) s^(-1) for the overall reaction rate constant of the hydroxy peroxy radical with NO. We also report the first clear experimental evidence of the (E-) form of the δ-hydroxyalkoxy channel through isotopic labeling experiments and quantify its branching ratio to be 0.1±0.025. Since it corresponds to missing carbon balance in isoprene oxidation, we have been able to identify some of the missing carbon balance. Since our measured isomeric selective rate constants for the dominant outer channel in OH initiated isoprene chemistry are similar to the overall rate constants derived from non isomeric kinetics, we predict that the remaining outer addition channel will have similar reactivity. We have extended this study to the OH initiated oxidation of 1,3-butadiene. We have obtained isomeric selective rate constants on the dominant channel of the butadiene oxidation chemistry and measured the branching ratio for the δ-hydroxyalkoxy channel. These results on butadiene studies will be discussed.

  13. Immunotoxic effects of the color additive caramel color III: immune function studies in rats.

    PubMed

    Houben, G F; Penninks, A H; Seinen, W; Vos, J G; Van Loveren, H

    1993-01-01

    Administration of the color additive caramel color III (AC) may cause a reduction in total white blood cell counts in rats due to reduced lymphocyte counts. Beside lymphopenia, several other effects in rat have been described. The effects are caused by the imidazole derivative 2-acetyl-4(5)-(1,2,3,4-tetrahydroxybutyl)imidazole (THI) and occur in rats fed a diet low in vitamin B6. In the present paper, immune function studies on AC and THI with rats fed a diet low, but not deficient in vitamin B6 are presented and discussed. Rats were exposed to 0.4 or 4% AC or to 5.72 ppm THI in drinking water during and for 28 days prior to the start of immune function assays. Resistance to Trichinella spiralis was examined in an oral infection model and clearance of Listeria monocytogenes upon an intravenous infection was studied. In addition, natural cell-mediated cytotoxicity of splenic and nonadherent peritoneal cells and the antibody response to sheep red blood cells were studied. From the results it is concluded that exposure of rats to AC or THI influenced various immune function parameters. Thymus-dependent immunity was suppressed, while parameters of the nonspecific resistance were also affected, as shown by a decreased natural cell-mediated cytotoxicity in the spleen and an enhanced clearance of L. monocytogenes. PMID:8432426

  14. Using a generalized additive model with autoregressive terms to study the effects of daily temperature on mortality

    PubMed Central

    2012-01-01

    Background Generalized Additive Model (GAM) provides a flexible and effective technique for modelling nonlinear time-series in studies of the health effects of environmental factors. However, GAM assumes that errors are mutually independent, while time series can be correlated in adjacent time points. Here, a GAM with Autoregressive terms (GAMAR) is introduced to fill this gap. Methods Parameters in GAMAR are estimated by maximum partial likelihood using modified Newton’s method, and the difference between GAM and GAMAR is demonstrated using two simulation studies and a real data example. GAMM is also compared to GAMAR in simulation study 1. Results In the simulation studies, the bias of the mean estimates from GAM and GAMAR are similar but GAMAR has better coverage and smaller relative error. While the results from GAMM are similar to GAMAR, the estimation procedure of GAMM is much slower than GAMAR. In the case study, the Pearson residuals from the GAM are correlated, while those from GAMAR are quite close to white noise. In addition, the estimates of the temperature effects are different between GAM and GAMAR. Conclusions GAMAR incorporates both explanatory variables and AR terms so it can quantify the nonlinear impact of environmental factors on health outcome as well as the serial correlation between the observations. It can be a useful tool in environmental epidemiological studies. PMID:23110601

  15. Alcoholic Steatosis in Different Strains of Rat: A Comparative Study

    PubMed Central

    Bhopale, Kamlesh K.; Kondraganti, Shakuntala; Fernando, Harshica; Boor, Paul J.; Kaphalia, Bhupendra S.; Shakeel Ansari, G. A.

    2016-01-01

    Background Different strains of rats have been used to study alcoholic liver disease (ALD) while the reason for selecting a particular rat strain was not apparent. Purpose The aim of our study was to compare outbred (Wistar) and inbred (Fischer) strains to evaluate pathological, biochemical changes, and gene expression differences associated with ethanol-induced early hepatic steatosis. Study Design Male Wistar and Fischer-344 rats were pair-fed for 6 weeks with or without 5% ethanol in Lieber-DeCarli liquid diet. Livers were analyzed for histological and lipid-related differences. Results Hepatic midzonal steatosis was mainly found in Wistar rats while Fischer rats showed mostly pericentral steatosis. Increased hepatic steatosis in ethanol-fed Wistar rats is supported by increases in lipids with related genes and transcription factors involved in fatty acid and triglyceride synthesis. Conclusion Our data showed that Fischer rats are relatively less prone to ethanol-mediated steatosis with pericentral lipid deposition pattern in the liver which is similar to humans and show no trace level of lipid accumulation in pair-fed controls as observed in Wistar (outbred) strain. Therefore, Fischer rats are better suited for lipid studies in an early development of ALD. PMID:27213081

  16. Comparative micromorphological study of wild and micropropagated Dioscorea bulbifera Linn.

    PubMed Central

    Sonibare, Mubo A.; Adeniran, Adedapo A.

    2014-01-01

    Objective To study the leaf epidermis of wild and micropropagated Dioscorea bulbifera Linn. (D. bulbifera) in order to document useful diagnostic features that may be employed for correct crude drug identification and to clear any taxonomic uncertainties in the micropropagated medicinal plant. Methods Growth responses of micropropagated D. bulbifera were observed on Murashige Skoog medium supplemented with 6-benzylamino purine (1.0 mg/L)+α-naphthaleneacetic acid (0.2 mg/L)+cysteine (20 mg/L) using nodal segments as explants. Leaves of the wild and micropropagated plants were studied microscopically. Results More than 80% shoot regeneration and formation of 10%-30% whitish-brown callus were observed within 3 weeks. The highest root proliferation was obtained from Murashige Skoog medium of 6-benzylamino purine (0.05 mg/L) and α-naphthaleneacetic acid (0.01 mg/L) with mean root length of (27.00±1.25) mm and elongated single shoot of mean length (38.00±11.09) mm. Leaf epidermal features that revealed similarities between the wild and micropropagated plants included amphistomatic condition, presence of mucilage, glandular unicellular trichome with multicellular head, polygonal cells with smooth walls, stomata type and shape. Slight variations included thick cuticular wall with closed stomata in wild plant compared to thin walled opened stomata in the in vitro plant. Opening of stomata accounted for larger average stomata sizes of (7.68±0.38) µm and (6.14±0.46) µm on the adaxial and abaxial surfaces, respectively of the micropropagated plant compared to the wild. Conclusions The diagnostic features obtained in the study could serve as a basis for proper identification for quality control for standardization of the medicinal plant. PMID:25182434

  17. Antiamoebic chemoprophylaxis using quinfamide in children: a comparative study.

    PubMed

    Padilla, Nicolas; Diaz, Rosalinda; Alarcon, Alfonso; Barreda, Roberto

    2002-04-20

    This study sought to examine whether the administration of quinfamide at 3- or 6-month intervals diminished the frequency of Entamoeba histolytica cysts in stool samples compared to controls. The prospective, longitudinal, randomized, single-blind study examined children from six primary schools in Celaya and Neutla, Guanajuato. Of the 1,524 students in these schools, we selected participants for the study as follows: Children were included in the study if their parents agreed in writing to the study and if the children demonstrated evidence of E. histolytica cysts after a parasitoscopic analysis by concentration (PSC) in three samples over consecutive days using Faust"s method. Those included in the study received a single 4.3-g/kg dose of quinfamide, and we performed PSC on days 5, 6, and 7 following dose administration to examine whether quinfamide had affected the presence of the cysts. The study participants who tested negative for cysts were divided into three groups: Group 1 had 102 patients who underwent quinfamide treatment and three CPS analyses after the 12 months of the study; Group 2 had 98 subjects who underwent the quinfamide treatment and three CPS analyses at months 3, 6, 9, and 12 after their entrance into the study; and Group 3 had 102 patients, who underwent the quinfamide treatment and series of three CPS analyses at months 6 and 12 of the study. All participants received the dose of quinfamide after providing stool samples and after a clinical gastrointestinal history was obtained. Further clinical gastrointestinal data were collected 5 days after the quintamide dose was administered. We used EpiInfo 6.0 for statistical analysis, calculating c2 and p values for the clinical data and the CPS data after the 12 months concluded. Of the initial samples of 1,524 subjects, 308 (20.2%) had Entamoebic cysts. Of these, six were further eliminated because they did not meet the inclusion requirements. At the conclusion of the study, Group 1 presented

  18. Contrasting tropical estuarine ecosystem functioning and stability: A comparative study

    NASA Astrophysics Data System (ADS)

    Villanueva, Maria Ching

    2015-03-01

    A comparative study of the Sine-saloum (Senegal) and Gambia (The Gambia) estuaries was performed based on trophic model outputs that describe the system structure and functioning. These trophic models were constructed such as to differentiate main energetic flows in the systems and express how climate change may have impacted ecosystem resilience to change. Estuarine fish assemblages are highly resilient despite exposure to vast hydrodynamic variations and stress. Coupled with strong anthropogenic-driven stresses such as fisheries and climate change, ecosystems may undergo severe regime shifts that may weaken their resilience and stability. Taxonomically related and morphologically similar species do not necessarily play similar ecological roles in these two ecosystems. Biomass and production in the Sine-saloum are concentrated at trophic levels (TLs) 2 and 3, while for the Gambia, both are concentrated at TL3. Higher TL biomasses in Gambia compared to Sine-Saloum may be explained by the latter ecosystem being characterized by inverse hypersalinity. Higher TL of production in Sine-Saloum is due to higher exploitations compared to Gambia where fishing activities are still less developed. High production and consumption rates of some groups in both ecosystems indicate high system productivity. Elevated productivity may be due to higher abundance of juvenile fishes in most groups that utilize the latter as refuge and/or nursery zones. Both ecosystems are phytoplankton-driven. Differences in group trophic and ecological roles are mainly due to adaptive responses of these species to seasonal and long-term climate and anthropogenic stressors. System indicators suggest different levels of ecosystem resilience and stability as a function of biodiversity. Relevance of other observations on ecosystem functioning and indicators in relation to perturbation is discussed.

  19. A water soluble additive to suppress respirable dust from concrete-cutting chainsaws: a case study.

    PubMed

    Summers, Michael P; Parmigiani, John P

    2015-01-01

    Respirable dust is of particular concern in the construction industry because it contains crystalline silica. Respirable forms of silica are a severe health threat because they heighten the risk of numerous respirable diseases. Concrete cutting, a common work practice in the construction industry, is a major contributor to dust generation. No studies have been found that focus on the dust suppression of concrete-cutting chainsaws, presumably because, during normal operation water is supplied continuously and copiously to the dust generation points. However, there is a desire to better understand dust creation at low water flow rates. In this case study, a water-soluble surfactant additive was used in the chainsaw's water supply. Cutting was performed on a free-standing concrete wall in a covered outdoor lab with a hand-held, gas-powered, concrete-cutting chainsaw. Air was sampled at the operator's lapel, and around the concrete wall to simulate nearby personnel. Two additive concentrations were tested (2.0% and 0.2%), across a range of fluid flow rates (0.38-3.8 Lpm [0.1-1.0 gpm] at 0.38 Lpm [0.1 gpm] increments). Results indicate that when a lower concentration of additive is used exposure levels increase. However, all exposure levels, once adjusted for 3 hours of continuous cutting in an 8-hour work shift, are below the Occupational Safety and Health Administration (OSHA) permissible exposure limit (PEL) of 5 mg/m(3). Estimates were made using trend lines to predict the fluid flow rates that would cause respirable dust exposure to exceed both the OSHA PEL and the American Conference of Governmental Industrial Hygienists (ACGIH®) threshold limit value (TLV). PMID:25714034

  20. Comparative study of radiation damage accumulation in Cu and Fe

    NASA Astrophysics Data System (ADS)

    Caturla, M. J.; Soneda, N.; Alonso, E.; Wirth, B. D.; Díaz de la Rubia, T.; Perlado, J. M.

    2000-01-01

    Bcc and fcc metals exhibit significant differences in behavior when exposed to neutron or heavy ion irradiation. Transmission electron microscopy (TEM) observations reveal that damage in the form of stacking fault tetrahedra (SFT) is visible in copper irradiated to very low doses, but that no damage is visible in iron irradiated to the same total dose. In order to understand and quantify this difference in behavior, we have simulated damage production and accumulation in fcc Cu and bcc Fe. We use 20 keV primary knock-on atoms (PKAs) at a homologous temperature of 0.25 of the melting point. The primary damage state was calculated using molecular dynamics (MD) with empirical, embedded-atom interatomic potentials. Damage accumulation was modeled using a kinetic Monte Carlo (kMC) algorithm to follow the evolution of all defects produced in the cascades. The diffusivities and binding energies of defects are input data for this simulation and were either extracted from experiments, the literature, or calculated using MD. MD simulations reveal that vacancy clusters are produced within the cascade core in the case of copper. In iron, most of the vacancies do not cluster during cooling of the cascade core and are available for diffusion. In addition, self-interstitial atom (SIA) clusters are produced in copper cascades but those observed in iron are smaller in number and size. The combined MD/kMC simulations reveal that the visible cluster densities obtained as a function of dose are at least one order of magnitude lower in Fe than in Cu. We compare the results with experimental measurements of cluster density and find excellent agreement between the simulations and experiments when small interstitial clusters are considered to be mobile as suggested by recent MD simulations.

  1. Augmenting a Waste Glass Mixture Experiment Study with Additional Glass Components and Experimental Runs

    SciTech Connect

    Piepel, Gregory F. ); Cooley, Scott K. ); Peeler, David K.; Vienna, John D. ); Edwards, Tommy B.

    2002-01-01

    A glass composition variation study (CVS) for high-level waste (HLW) stored in Idaho is being statistically designed and performed in phases over several years. The purpose of the CVS is to investigate and model how HLW-glass properties depend on glass composition. The resulting glass property-composition models will be used to develop desirable glass formulations and for other purposes. Phases 1 and 2 of the CVS have been completed and are briefly described. This paper focuses on the CVS Phase 3 experimental design, which was chosen to augment the Phase 1 and 2 data with additional data points, as well as to account for additional glass components not studied in Phases 1 and/or 2. In total, 16 glass components were varied in the Phase 3 experimental design. The paper describes how these Phase 3 experimental design augmentation challenges were addressed using the previous data, preliminary property-composition models, and statistical mixture experiment and optimal experimental design methods and software.

  2. A comparative study of a new cardiotocography analysis program.

    PubMed

    Chen, Chen-Yu; Chen, Ju-Cheng; Yu, Chun; Lin, Chii-Wann

    2009-01-01

    Cardiotocography (CTG) is a frequently used technique of fetal monitoring to evaluate the well being of the fetus during pregnancy and in labor. The surveillance technique depends on the analysis of characteristic fetal heart rate patterns and uterine contractions. Computerized analyses can mitigate the intra-observer and inter-observer variability of visual CTG recording explanation, decrease the examination time, and the need of additional tests for fetal health. Several studies also showed that the signal processing techniques could help to determine the fetal heart rate (FHR) patterns, but all of them were only suitable for physicians. Following the criteria and consensuses of National Institute of Child Health and Human Development in April 2008, we developed a LabVIEW based FHR and uterine contraction (UC) pattern analysis software. This software has great potential for home-care use. The signal processing methods utilized in this study are median filter and peak/valley detection method. The analysis performance was verified by nineteen pregnant women's data. The accuracy of FHR baseline, baseline variability, early deceleration, UC frequency and NST all reach 100%. The accuracy of acceleration frequency reaches 90%. The accuracy of late and variable decelerations reaches 95%. PMID:19965213

  3. Comparative Study of Naugle and Hertel Exophthalmometry in Orbitozygomatic Fracture.

    PubMed

    Jeon, Hong Bae; Kang, Dong Hee; Oh, Sang Ah; Gu, Ja Hea

    2016-01-01

    Accurate perioperative evaluation of enophthalmos is important to determine the adequacy of surgical repair in orbitozygomatic fracture. In this study, the authors evaluated the degree of enophthalmos using Hertel and Naugle exophthalmometry in patients with pure blowout fracture and orbitozygomatic fracture, and compared the results. Fifty patients were divided into 2 groups: pure blowout fracture (Group A: control group, 25 patients) and orbitozygomatic fracture with displaced lateral orbital rim (Group B: experimental group, 25 patients). Hertel and Naugle scales were measured before and 6 months after surgery. The degree of lateral orbital rim advancement was assessed by comparing the difference between the perioperative change of the Hertel and Naugle scales. In Group A, the difference between the pre- and postoperative scales in the 2 exophthalmometry was statistically significant (P < 0.05). In Group B, the Hertel scale increased from -0.20 to -0.16 mm, with an insignificant difference between pre- and postoperative values (P > 0.05) and the Naugle scale increased from -0.88 to -0.20 mm, with a significant difference (P < 0.05). The Δ Hertel scale differed from the Δ Naugle scale by a mean of -0.64 mm, which represents the degree of lateral orbital rim advancement. Naugle exophthalmometry is a more reliable method for evaluation of enophthalmos in lateral orbital rim displaced orbitozygomatic fractures than Hertel exophthalmometry. The degree of lateral orbital rim advancement can be assessed by combined use of the Hertel and Naugle exophthalmometry in orbitozygomatic fractures. PMID:26674913

  4. Evolutionary algorithms, simulated annealing, and Tabu search: a comparative study

    NASA Astrophysics Data System (ADS)

    Youssef, Habib; Sait, Sadiq M.; Adiche, Hakim

    1998-10-01

    Evolutionary algorithms, simulated annealing (SA), and Tabu Search (TS) are general iterative algorithms for combinatorial optimization. The term evolutionary algorithm is used to refer to any probabilistic algorithm whose design is inspired by evolutionary mechanisms found in biological species. Most widely known algorithms of this category are Genetic Algorithms (GA). GA, SA, and TS have been found to be very effective and robust in solving numerous problems from a wide range of application domains.Furthermore, they are even suitable for ill-posed problems where some of the parameters are not known before hand. These properties are lacking in all traditional optimization techniques. In this paper we perform a comparative study among GA, SA, and TS. These algorithms have many similarities, but they also possess distinctive features, mainly in their strategies for searching the solution state space. the three heuristics are applied on the same optimization problem and compared with respect to (1) quality of the best solution identified by each heuristic, (2) progress of the search from initial solution(s) until stopping criteria are met, (3) the progress of the cost of the best solution as a function of time, and (4) the number of solutions found at successive intervals of the cost function. The benchmark problem was is the floorplanning of very large scale integrated circuits. This is a hard multi-criteria optimization problem. Fuzzy logic is used to combine all objective criteria into a single fuzzy evaluation function, which is then used to rate competing solutions.

  5. Clobetasone treatment of allergic conjunctivitis: a comparative double blind study.

    PubMed

    Cerqueti, P M; Prosio, P E; Bosia, S; Buscaglia, S; Ciprandi, G

    1993-01-01

    Glucocorticosteroids are often included in the treatment of allergic conjunctivitis. The present study compares the efficacy on clinical and cytological parameters and safety of topical clobetasone butyrate compared to placebo. The trial, designed as double blind, randomized and parallel group treatment, was carried out in 30 patients, suffering from seasonal allergic conjunctivitis due to Grass pollen, during the pollen season (June 1992). Patients received clobetasone butyrate 0.1% eye drops or placebo eye drops, two drops each eye, t.i.d. for 10 days. The clinical and cytological evidences were investigated on admission and at the end of treatment by clinicians and by patients on a dairy card. The steroid group showed a rapid and significant clinical improvement and at the end of the trial a statistically significant difference was evidenced between the active drug treated group and placebo treated group. No serious side effects were observed. The results show the clinical efficacy of clobetasone butyrate in the treatment of pollen-induced allergic conjunctivitis. PMID:8337991

  6. Role of sulfite additives in wine induced asthma: single dose and cumulative dose studies

    PubMed Central

    Vally, H; Thompson, P

    2001-01-01

    BACKGROUND—Wine appears to be a significant trigger for asthma. Although sulfite additives have been implicated as a major cause of wine induced asthma, direct evidence is limited. Two studies were undertaken to assess sulfite reactivity in wine sensitive asthmatics. The first study assessed sensitivity to sulfites in wine using a single dose sulfited wine challenge protocol followed by a double blind, placebo controlled challenge. In the second study a cumulative dose sulfited wine challenge protocol was employed to establish if wine sensitive asthmatics as a group have an increased sensitivity to sulfites.
METHODS—In study 1, 24 asthmatic patients with a strong history of wine induced asthma were screened. Subjects showing positive responses to single blind high sulfite (300 ppm) wine challenge were rechallenged on separate days in a double blind, placebo controlled fashion with wines of varying sulfite levels to characterise their responses to these drinks. In study 2, wine sensitive asthmatic patients (n=12) and control asthmatics (n=6) were challenged cumulatively with wine containing increasing concentrations of sulfite in order to characterise further their sensitivity to sulfites in wine.
RESULTS—Four of the 24 self-reporting wine sensitive asthmatic patients were found to respond to sulfite additives in wine when challenged in a single dose fashion (study 1). In the double blind dose-response study all four had a significant fall in forced expiratory volume in one second (FEV1) (>15% from baseline) following exposure to wine containing 300 ppm sulfite, but did not respond to wines containing 20, 75 or 150 ppm sulfite. Responses were maximal at 5 minutes (mean (SD) maximal decline in FEV1 28.7 (13)%) and took 15-60 minutes to return to baseline levels. In the cumulative dose-response study (study 2) no significant difference was observed in any of the lung function parameters measured (FEV1, peak expiratory flow (PEF), mid phase forced expiratory

  7. Characterization studies on the additives mixed L-arginine phosphate monohydrate (LAP) crystals

    NASA Astrophysics Data System (ADS)

    Haja Hameed, A. S.; Karthikeyan, C.; Ravi, G.; Rohani, S.

    2011-04-01

    L-arginine phosphate monohydrate (LAP), potassium thiocyanate (KSCN) mixed LAP (LAP:KSCN) and sodium sulfite (Na 2SO 3) mixed LAP (LAP:Na 2SO 3) single crystals were grown by slow cooling technique. The effect of microbial contamination and coloration on the growth solutions was studied. The crystalline powders of the grown crystals were examined by X-ray diffraction and the lattice parameters of the crystals were estimated. From the FTIR spectroscopic analysis, various functional group frequencies associated with the crystals were assigned. Vickers microhardness studies were done on {1 0 0} faces for pure and additives mixed LAP crystals. From the preliminary surface second harmonic generation (SHG) results, it was found that the SHG intensity at (1 0 0) face of LAP:KSCN crystal was much stronger than that of pure LAP.

  8. The guanidine and maleic acid (1:1) complex. The additional theoretical and experimental studies

    NASA Astrophysics Data System (ADS)

    Drozd, Marek; Dudzic, Damian

    2012-04-01

    On the basis of experimental literature data the theoretical studies for guanidinium and maleic acid complex with using DFT method are performed. In these studies the experimental X-ray data for two different forms of investigated crystal were used. During the geometry optimization process one equilibrium structure was found, only. According to this result the infrared spectrum for one theoretical molecule was calculated. On the basis of potential energy distribution (PED) analysis the clear-cut assignments of observed bands were performed. For the calculated molecule with energy minimum the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) were obtained and graphically illustrated. The energy difference (GAP) between HOMO and LUMO was analyzed. Additionally, the nonlinear properties of this molecule were calculated. The α and β (first and second order) hyperpolarizability values are obtained. On the basis of these results the title crystal was classified as new second order NLO generator.

  9. A comparative study of the vibration damping capacity of superalloys

    SciTech Connect

    Wang, J.; Chung, D.D.L.

    1999-10-01

    A comparative study of nickel-base, iron-base, and iron-nickel base superalloys showed Inconel MA754 (oxide dispersion strengthened) to be particularly high in vibration damping capacity. Dynamic mechanical testing was performed using a Perkin-Elmer Corp. (Norwalk, Connecticut) DMA7e instrument under dynamic flexure by three-point bending at a frequency of 0.2 Hz, with a displacement in the range of 5 to 9 {micro}m and a temperature of 475 C. The span in three-point bending was 20 mm. The sample length (in the span direction) was in the range of 20 to 25 mm. The sample width was 6 mm or less, and the sample thickness was in the range of 0.5 to 1.2 mm. The loss tangent, tan {delta}, and storage modulus were measured simultaneously.

  10. [Comparative study of discriminative stimulus properties of antidepressants].

    PubMed

    Korolev, A O; Kalinina, T S; Volkova, A V; Mokrov, G V; Kudriashov, N V; Voronina, T A

    2014-01-01

    Interoceptive stimulus properties of amitriptyline (54 mg/kg body weight), fluoxetine (10 mg/kg), and pyrrolo[1,2-a][1,4]diazepine derivative GMAL-24 (10 mg/kg) were studied in a standard operant model with liquid reinforcement of drug discrimination (DD) in male Wistar rats. A new experimental schedule that includes subchronic (7-day) administration of a training drug was used to perform DD learning. For the first time, it was found that amitriptyline has a discriminative interoceptive stimulus properties. Neither fluoxetine nor GMAL-24 did exhibit interoceptive properties. Imipramine (15 mg/kg, i.p.) fully substitutes for amitriptyline stimulus in substitution test. Fluoxetine (5 - 20 mg/kg, i.p.) failed to substitute with amitriptyline. Thus, amitriptyline/saline drug discrimination should be used for a comparative analysis of the central mechanisms of action of psychotropic substances, rather than for screening specific antidepressant activity. PMID:25322645

  11. A comparative study of two stochastic mode reduction methods

    SciTech Connect

    Stinis, Panagiotis

    2005-09-01

    We present a comparative study of two methods for thereduction of the dimensionality of a system of ordinary differentialequations that exhibits time-scale separation. Both methods lead to areduced system of stochastic differential equations. The novel feature ofthese methods is that they allow the use, in the reduced system, ofhigher order terms in the resolved variables. The first method, proposedby Majda, Timofeyev and Vanden-Eijnden, is based on an asymptoticstrategy developed by Kurtz. The second method is a short-memoryapproximation of the Mori-Zwanzig projection formalism of irreversiblestatistical mechanics, as proposed by Chorin, Hald and Kupferman. Wepresent conditions under which the reduced models arising from the twomethods should have similar predictive ability. We apply the two methodsto test cases that satisfy these conditions. The form of the reducedmodels and the numerical simulations show that the two methods havesimilar predictive ability as expected.

  12. ICD-10 mortality coding and the NCIS: a comparative study.

    PubMed

    Daking, Leanne; Dodds, Leonie

    2007-01-01

    The collection and utilisation of mortality data are often hindered by limited access to contextual details of the circumstances surrounding fatal incidents. The National Coroners Information System (NCIS) can provide researchers with access to such information. The NCIS search capabilities have been enhanced by the inclusion of data supplied by the Australian Bureau of Statistics (ABS), specifically the ICD-10 Cause of Death code set. A comparative study was conducted to identify consistencies and differences between ABS ICD-10 codes and those that could be generated by utilising the full NCIS record. Discrepancies between the two sets of codes were detected in over 50% of cases, which highlighted the importance of access to complete and timely documentation in the assignment of accurate and detailed cause of death codes. PMID:18195402

  13. A comparative study of two different clear aligner systems

    PubMed Central

    2014-01-01

    Background This study aims to compare the ‘Nuvola®’ system with ‘Fantasmino®’ system, examine their material properties, and define the indications for use of the aligners. Methods Two groups of patients were selected and were respectively treated with Nuvola® aligner and Fantasmino® system. Results The goal of treatment has been achieved with the two systems. Conclusions The two types of aligners have shown differences during the treatment. Fantasmino® system has elastic properties of high performance, but its size does not encourage compliance throughout the day. Nuvola® system determines good tooth movement and its size facilitates the patient’s collaboration. In both aligner systems, difficulties were found in the correction of torque information and rotations. PMID:24934094

  14. Magnetic Field Configuration Models and Reconstruction Methods: a comparative study

    NASA Astrophysics Data System (ADS)

    Al-haddad, Nada; Möstl, Christian; Roussev, Ilia; Nieves-Chinchilla, Teresa; Poedts, Stefaan; Hidalgo, Miguel Angel; Marubashi, Katsuhide; Savani, Neel

    2012-07-01

    This study aims to provide a reference to different magnetic field models and reconstruction methods. In order to understand the dissimilarities of those models and codes, we analyze 59 events from the CDAW list, using four different magnetic field models and reconstruction techniques; force- free reconstruction (Lepping et al.(1990); Lynch et al.(2003)), magnetostatic reconstruction, referred as Grad-Shafranov (Hu & Sonnerup(2001); Mostl et al.(2009)), cylinder reconstruction (Marubashi & Lepping(2007)), elliptical, non-force free (Hidalgo et al.(2002)). The resulted parameters of the reconstructions, for the 59 events are compared, statistically, as well as in more details for some cases. The differences between the reconstruction codes are discussed, and suggestions are provided as how to enhance them. Finally we look at 2 unique cases under the microscope, to provide a comprehensive idea of the different aspects of how the fitting codes work.

  15. Anatomopathological findings in scars: comparative study between different specimens.

    PubMed

    Munteanu, Andrada Despina; Bedereag, Ştefan Iulian; NiŢescu, Cristian; Florescu, Ioan Petre

    2015-01-01

    In spite of the remarkable progress science and medicine have experienced, many facts concerning healing processes and pathological scars are still unknown or incompletely explained. This paper is part of a larger study (research for a PhD thesis) concerning new approaches in the prevention and treatment of pathological post-burn scars. We present and analyze the cases of some patients who developed abnormal scars in order to understand and point out the characteristics, that different types of pathological scars have in common and how we can differentiate them. Knowing what issue to address is the key to any successful therapy. Thus, the information we obtained will help us in applying more appropriate and efficient methods of treatment and in our further research: comparing the efficiency of newer therapies to that of older ones. PMID:25826518

  16. A Comparative Study : Microprogrammed Vs Risc Architectures For Symbolic Processing

    NASA Astrophysics Data System (ADS)

    Heudin, J. C.; Metivier, C.; Demigny, D.; Maurin, T.; Zavidovique, B.; Devos, F.

    1987-05-01

    It is oftenclaimed that conventional computers are not well suited for human-like tasks : Vision (Image Processing), Intelligence (Symbolic Processing) ... In the particular case of Artificial Intelligence, dynamic type-checking is one example of basic task that must be improved. The solution implemented in most Lisp work-stations consists in a microprogrammed architecture with a tagged memory. Another way to gain efficiency is to design a well suited instruction set for symbolic processing, which reduces the semantic gap between the high level language and the machine code. In this framework, the RISC concept provides a convenient approach to study new architectures for symbolic processing. This paper compares both approaches and describes our projectof designing a compact symbolic processor for Artificial Intelligence applications.

  17. Advanced general aviation comparative engine/airframe integration study

    NASA Technical Reports Server (NTRS)

    Huggins, G. L.; Ellis, D. R.

    1981-01-01

    The NASA Advanced Aviation Comparative Engine/Airframe Integration Study was initiated to help determine which of four promising concepts for new general aviation engines for the 1990's should be considered for further research funding. The engine concepts included rotary, diesel, spark ignition, and turboprop powerplants; a conventional state-of-the-art piston engine was used as a baseline for the comparison. Computer simulations of the performance of single and twin engine pressurized aircraft designs were used to determine how the various characteristics of each engine interacted in the design process. Comparisons were made of how each engine performed relative to the others when integrated into an airframe and required to fly a transportation mission.

  18. Prazosin addition to fluvoxamine: A preclinical study and open clinical trial in OCD.

    PubMed

    Feenstra, Matthijs G P; Klompmakers, André; Figee, Martijn; Fluitman, Sjoerd; Vulink, Nienke; Westenberg, Herman G M; Denys, Damiaan

    2016-02-01

    The efficacy of selective serotonin reuptake inhibitors (SRIs) in psychiatric disorders may be "augmented" through the addition of atypical antipsychotic drugs. A synergistic increase in dopamine (DA) release in the prefrontal cortex has been suggested to underlie this augmentation effect, though the mechanism of action is not clear yet. We used in vivo microdialysis in rats to study DA release following the administration of combinations of fluvoxamine (10 mg/kg) and quetiapine (10 mg/kg) with various monoamine-related drugs. The results confirmed that the selective 5-HT1A antagonist WAY-100635 (0.05 mg/kg) partially blocked the fluvoxamine-quetiapine synergistic effect (maximum DA increase dropped from 325% to 214%). A novel finding is that the α1-adrenergic blocker prazosin (1 mg/kg), combined with fluvoxamine, partially mimicked the effect of augmentation (maximum DA increase 205%; area-under-the-curve 163%). As this suggested that prazosin augmentation might be tested in a clinical study, we performed an open clinical trial of prazosin 20 mg addition to SRI in therapy-resistant patients with obsessive-compulsive disorder applying for neurosurgery. A small, non-significant reduction in Yale Brown Obsessive Compulsive Scale (Y-BOCS) scores was observed in 10 patients and one patient was classified as a responder with a reduction in Y-BOCS scores of more than 25%. We suggest that future clinical studies augmenting SRIs with an α1-adrenergic blocker in less treatment resistant cases should be considered. The clinical trial "Prazosin in combination with a serotonin reuptake inhibitor for patients with Obsessive Compulsive disorder: an open label study" was registered at 24/05/2011 under trial number ISRCTN61562706: http://www.controlled-trials.com/ISRCTN61562706. PMID:26712326

  19. Comparative study of the synthesis of layered transition metal molybdates

    NASA Astrophysics Data System (ADS)

    Mitchell, S.; Gómez-Avilés, A.; Gardner, C.; Jones, W.

    2010-01-01

    Mixed metal oxides (MMOs) prepared by the mild thermal decomposition of layered double hydroxides (LDHs) differ in their reactivity on exposure to aqueous molybdate containing solutions. In this study, we investigate the reactivity of some T-Al containing MMOs ( T=Co, Ni, Cu or Zn) towards the formation of layered transition metal molybdates (LTMs) possessing the general formula AT2(OH)(MoO 4) 2·H 2O, where A=NH 4+, Na + or K +. The phase selectivity of the reaction was studied with respect to the source of molybdate, the ratio of T to Mo and the reaction pH. LTMs were obtained on reaction of Cu-Al and Zn-Al containing MMOs with aqueous solutions of ammonium heptamolybdate. Rehydration of these oxides in the presence of sodium or potassium molybdate yielded a rehydrated LDH phase as the only crystalline product. The LTM products obtained by the rehydration of MMO precursors were compared with LTMs prepared by direct precipitation from the metal salts in order to study the influence of preparative route on their chemical and physical properties. Differences were noted in the composition, morphology and thermal properties of the resulting products.

  20. Biofragmentable bowel anastomosis ring: comparative efficacy studies in dogs.

    PubMed

    Maney, J W; Katz, A R; Li, L K; Pace, W G; Hardy, T G

    1988-01-01

    Three studies were conducted in a total of 178 dogs to determine the efficacy of a biofragmentable bowel anastomosis ring (BAR) composed of polyglycolic acid and 12.5% barium sulfate. Wound strength and healing of BAR, suture, and staple colonic anastomoses were compared for intervals of up to 1 year. The effect of systemic steroid treatment and BAR size on anastomotic wound strength and healing was also studied. The BARs fragmented at a mean time of 15.06 days postoperatively and were passed in the feces without injury. Wound strength was determined by measurements of the pressure required to burst the anastomosed colonic segment and measurements of the tension required to break 10 mm wide longitudinal strips of the anastomosed segment. The studies demonstrated that wound strength had progressed to a point where continued mechanical support (with sutures or staples) was no longer required by 14 days in both nontreated and steroid-treated dogs. Gross healing evaluations at 21 days and beyond showed no differences due to anastomotic method. Microscopic evaluations suggested that residual granulation tissue was less at the sites of BAR asastomoses than at sites of suture or staple anastomoses at the 1-year interval, suggesting that healing may be better with BAR than with standard methods of colon anastomosis. PMID:3336869

  1. Psychological profile of women with infertility: A comparative study

    PubMed Central

    Poddar, Shuvabrata; Sanyal, Nilanjana; Mukherjee, Urbi

    2014-01-01

    Background: An endeavour to probe into the psychological profile of infertile women in a comparative stance with the fertile women is not very common. This study is an attempt to explore the possible non-apparent personality factors which contribute to the unexplained pain of infertility. Methods: The main objectives of the present study were (a) to examine whether infertile women are different from fertile women in terms of selected psychological variables- narcissistic components, dimensions of attachment style and uses of defensive manoeuvres; and (b) whether the primary infertile women (n=18) are different from the secondary infertile women (n=12) with respect to those variables. A total of 60 individuals (30 infertile women and 30 matched fertile women) were assessed through Attachment Style Questionnaire (ASQ), Narcissistic Personality Inventory (NPI) and Defense Style Questionnaire (DSQ-40). General Health Questionnaire (GHQ) was administered on to the fertile women to rule out the psychiatric morbidity. Results: Findings revealed that infertile women group differed from fertile women group with respect to narcissism, dimensions of attachment style and uses of defense mechanism. The primary infertile group also showed marked difference from the secondary infertile group with respect to those variables. Conclusions: This study endeavours to enrich the knowledge regarding the personality dynamics of infertile women to design psychotherapeutic programme to aid their well-being, help them to cherish the flavour of parenthood and improve their quality of life. PMID:25788801

  2. The comparative study of solvents to expedite removal of bitumen.

    PubMed

    Iuchi, Manabu; Sugiyama, Masahide; Oyatsu, Yasuyuki; Fukai, Takao

    2009-03-01

    Hot-bitumen burn is a unique case in all types of burns. This melting substance is difficult to remove when it adheres to the skin and solidifies. It causes burns and sticks to the skin when it is cooled to the skin temperature. Some reports are available on many kinds of solvents for the removal of solid bitumen. However, there have thus far been no comparative studies. It is necessary to seek for an optimum method to remove bitumen without consuming so much time and with minimum injury to the skin. The selected solvents in this study were petrolatum, olive oil, salad oil, butter, Neosporin ointment and De-solv-it. They were often reported as being effective for hot-bitumen burn injuries with little irritation for a damaged skin. It is easy to purchase them commercially. Each solvent was poured over the bitumen in a test tube. Afterwards, the concentrations of the bitumen in the solvents were quantified with the fluorescence measurement technique. We consider De-solv-it is the one of the best solvent for the removal of bitumen and highly recommended for hot-bitumen burns. The results of this study suggest that dressing change should be done every 4 to 8 h or as frequently as needed until the bitumen is entirely removed. PMID:18789588

  3. Institutions and national development in Latin America: a comparative study

    PubMed Central

    Portes, Alejandro; Smith, Lori D.

    2013-01-01

    We review the theoretical and empirical literatures on the role of institutions on national development as a prelude to present a more rigorous and measurable definition of the concept and a methodology to study this relationship at the national and subnational levels. The existing research literature features conflicting definitions of the concept of “institutions” and empirical tests based mostly on reputational indices, with countries as units of analysis. The present study’s methodology is based on a set of five strategic organizations studied comparatively in five Latin American countries. These include key federal agencies, public administrative organizations, and stock exchanges. Systematic analysis of results show a pattern of differences between economically-oriented institutions and those entrusted with providing basic services to the general population. Consistent differences in institutional quality also emerge across countries, despite similar levels of economic development. Using the algebraic methods developed by Ragin, we test six hypotheses about factors determining the developmental character of particular institutions. Implications of results for theory and for methodological practices of future studies in this field are discussed. PMID:26543407

  4. Comparing the Leadership Styles of Two Heads of Department at Carnelian School: Comparative Case Studies

    ERIC Educational Resources Information Center

    Parascandalo, Marthese

    2014-01-01

    The purpose of this dissertation was to compare and contrast the Leadership Styles of two Heads of Department who work at Carnelian Secondary School (anonymized). It augments a previous paper (Parascandalo 2011) which examined the role of the middle leader in secondary schools in educational literature. The investigation by means of two…

  5. Pain assessment of the intratympanic injections: a prospective comparative study.

    PubMed

    Belhassen, Sarah; Saliba, Issam

    2012-12-01

    The objective of the study is to compare the pain level of three methods of intratympanic (IT) injections using prospective, randomized clinical study in a tertiary care center. 39 patients with Ménière's disease and 30 patients with sudden sensorineural hearing loss are included. Excluded were patients treated for a chronic pain or those who took any pain killer for the last 24 h. Each patient received one IT injection a week, for three consecutive weeks. Three methods of IT injections were compared, with the application of EMLA cream on the tympanic membrane filling the external auditory canal 60 min before the procedure, with subcutaneous injection of lidocaine 1% with 1:100,000 epinephrine in the external auditory canal, and finally with an IT injection without any previous anesthesia. The pain intensity was immediately measured at 5 min, and then 45 min after the procedure, each time using four pain rating scales (visual analogue scale, numerical rating scale, verbal rating scale and categorical rating scale). No difference in pain intensity between the three methods of IT injections was detected by the visual analogue scale and numerical rating scale (p > 0.05). 45.8% of patients preferred the IT injection without previous anesthesia. However, methylprednisolone has been associated with pain intensity greater than that of gentamicin 45 min after the injection (p < 0.05). The IT injection performed without any previous anesthesia is an interesting option since it has not been shown to be more painful than the other methods of injections, and spares the patient from disadvantages associated with the anesthesia. PMID:22203120

  6. Malaria and risk of predation: a comparative study of birds.

    PubMed

    Møller, Anders Pape; Nielsen, Jan Tøttrup

    2007-04-01

    Predators have been hypothesized to prey on individuals in a poor state of health, although this hypothesis has only rarely been examined. We used extensive data on prey abundance and availability from two long-term studies of the European Sparrowhawk (Accipiter nisus) and the Eurasian Goshawk (Accipiter gentilis) to quantify the relationship between predation risk of different prey species and infection with malaria and other protozoan blood parasites. Using a total of 31 745 prey individuals of 65 species of birds from 1709 nests during 1977-1997 for the Sparrowhawk and a total of 21 818 prey individuals of 76 species of birds from 1480 nests for the Goshawk during 1977-2004, we show that prey species with a high prevalence of blood parasites had higher risks of predation than species with a low prevalence. That was also the case when a number of confounding variables of prey species, such as body mass, breeding sociality, sexual dichromatism, and similarity among species in risk of predation due to common descent, were controlled in comparative analyses of standardized linear contrasts. Prevalence of the genera Haemoproteus, Leucocytozoon, Plasmodium, and Trypanosoma were correlated with each other, and we partitioned out the independent effects of different protozoan genera on predation risk in comparative analyses. Prevalence of Haemoproteus, Leucocytozoon, and Plasmodium accounted for interspecific variation in predation risk for the two raptors. These findings suggest that predation is an important factor affecting parasite-host dynamics because predators tend to prey on hosts that are more likely to be infected, thereby reducing the transmission success of parasites. Furthermore, this study demonstrates that protozoan infections are a common cause of death for hosts mediated by increased risk of predation. PMID:17536704

  7. Systemic Inflammation in Cardiovascular and Periodontal Disease: Comparative Study

    PubMed Central

    Glurich, Ingrid; Grossi, Sara; Albini, Boris; Ho, Alex; Shah, Rashesh; Zeid, Mohamed; Baumann, Heinz; Genco, Robert J.; De Nardin, Ernesto

    2002-01-01

    Epidemiological studies have implicated periodontal disease (PD) as a risk factor for the development of cardiovascular disease (CVD). These studies addressed the premise that local infection may perturb the levels of systemic inflammatory mediators, thereby promoting mechanisms of atherosclerosis. Levels of inflammatory mediators in the sera of subjects with only PD, only CVD, both diseases, or neither condition were compared. Subjects were assessed for levels of C-reactive protein (CRP), serum amyloid A (SAA), ceruloplasmin, α1-acid-glycoprotein (AAG), α1-antichymotrypsin (ACT), and the soluble cellular adhesion molecules sICAM-1 and sVCAM by enzyme-linked immunoabsorbent and/or radial immunodiffusion assays. CRP levels in subjects with either condition alone were elevated twofold above subjects with neither disease, whereas a threefold increase was noted in subjects with both diseases (P = 0.0389). Statistically significant increases in SAA and ACT were noted in subjects with both conditions compared to those with one or neither condition (P = 0.0162 and 0.0408, respectively). Ceruloplasmin levels were increased in subjects with only CVD (P = 0.0001). Increases in sVCAM levels were noted in all subjects with CVD (P = 0.0054). No differences in sICAM levels were noted among subject groups. A trend toward higher levels of AAG was noted in subjects with both conditions and for ACT in subjects with only PD. Immunohistochemical examination of endarterectomy specimens of carotid arteries from subjects with atherosclerosis documented SAA and CRP deposition in association with atheromatous lesions. The data support the hypothesis that localized persistent infection may influence systemic levels of inflammatory mediators. Changes in inflammatory mediator levels potentially impact inflammation-associated atherosclerotic processes. PMID:11874889

  8. Comparative studies of brain activation with MEG and functional MRI

    SciTech Connect

    George, J.S.; Aine, C.J.; Sanders, J.A.; Lewine, J.D.; Caprihan, A.

    1993-12-31

    The past two years have witnessed the emergence of MRI as a functional imaging methodology. Initial demonstrations involved the injection of a paramagnetic contrast agent and required ultrafast echo planar imaging capability to adequately resolve the passage of the injected bolus. By measuring the local reduction in image intensity due to magnetic susceptibility, it was possible to calculate blood volume, which changes as a function of neural activation. Later developments have exploited endogenous contrast mechanisms to monitor changes in blood volume or in venous blood oxygen content. Recently, we and others have demonstrated that it is possible to make such measurements in a clinical imager, suggesting that the large installed base of such machines might be utilized for functional imaging. Although it is likely that functional MRI (fMRI) will subsume some of the clinical and basic neuroscience applications now touted for MEG, it is also clear that these techniques offer different largely complementary, capabilities. At the very least, it is useful to compare and cross-validate the activation maps produced by these techniques. Such studies will be valuable as a check on results of neuromagnetic distributed current reconstructions and will allow better characterization of the relationship between neurophysiological activation and associated hemodynamic changes. A more exciting prospect is the development of analyses that combine information from the two modalities to produce a better description of underlying neural activity than is possible with either technique in isolation. In this paper we describe some results from initial comparative studies and outline several techniques that can be used to treat MEG and fMRI data within a unified computational framework.

  9. Gasification of New Zealand coals: a comparative simulation study

    SciTech Connect

    Smitha V. Nathen; Robert D. Kirkpatrick; Brent R. Young

    2008-07-15

    The aim of this study was to conduct a preliminary feasibility assessment of gasification of New Zealand (NZ) lignite and sub-bituminous coals, using a commercial simulation tool. Gasification of these coals was simulated in an integrated gasification combined cycle (IGCC) application and associated preliminary economics compared. A simple method of coal characterization was developed for simulation purposes. The carbon, hydrogen, and oxygen content of the coal was represented by a three component vapor solid system of carbon, methane, and water, the composition of which was derived from proximate analysis data on fixed carbon and volatile matter, and the gross calorific value, both on a dry, ash free basis. The gasification process was modeled using Gibb's free energy minimization. Data from the U.S. Department of Energy's Shell Gasifier base cases using Illinios No. 6 coal was used to verify both the gasifier and the IGCC flowsheet models. The H:C and O:C ratios of the NZ coals were adjusted until the simulated gasifier output composition and temperature matched the values with the base case. The IGCC power output and other key operating variables such as gas turbine inlet and exhaust temperatures were kept constant for study of comparative economics. The results indicated that 16% more lignite than sub-bituminous coal was required. This translated into the requirement of a larger gasifier and air separation unit, but smaller gas and steam turbines were required. The gasifier was the largest sole contributor (30%) to the estimated capital cost of the IGCC plant. The overall cost differential associated with the processing of lignite versus processing sub-bituminous coal was estimated to be of the order of NZ $0.8/tonne. 13 refs., 9 tabs.

  10. Study on Type C Coal Fly ash as an Additive to Molding Sand for Steel Casting

    NASA Astrophysics Data System (ADS)

    Palaniappan, Jayanthi

    2016-05-01

    Study of physio-chemical properties studies such as granulometric analysis, moisture, X ray fluorescence etc. were performed with Type C coal—combustion fly ash to investigate their potential as a distinct option for molding sand in foundry, thereby reducing the dependency on latter. Technological properties study such as compressive strength, tensile strength, permeability and compaction of various compositions of fly ash molding sand (10, 20 and 30 % fly ash substitute to chemically bonded sand) were performed and compared with silica molding sand. Steel casting production using this fly ash molding sand was done and the casting surface finish and typical casting parameters were assessed. It was noted that a good quality steel casting could be produced using type C fly ash molding sand, which effectively replaced 20 % of traditional molding sand and binders thereby providing greater financial profits to the foundry and an effective way of fly ash utilization (waste management).

  11. International Comparative Studies in Education: Descriptions of Selected Large-Scale Assessments and Case Studies.

    ERIC Educational Resources Information Center

    National Academy of Sciences - National Research Council, Washington, DC. Commission on Behavioral and Social Sciences and Education.

    Since its inception in 1988, the Board on International Comparative Studies in Education (BICSE) has monitored U.S. participation in those cross national comparative studies in education that are funded by its sponsors, the National Science Foundation and the National Center for Education Statistics. This set of international study descriptions…

  12. A study of pyrazines in cigarettes and how additives might be used to enhance tobacco addiction

    PubMed Central

    Alpert, Hillel R; Agaku, Israel T; Connolly, Gregory N

    2016-01-01

    Background Nicotine is known as the drug that is responsible for the addicted behaviour of tobacco users, but it has poor reinforcing effects when administered alone. Tobacco product design features enhance abuse liability by (A) optimising the dynamic delivery of nicotine to central nervous system receptors, and affecting smokers’ withdrawal symptoms, mood and behaviour; and (B) effecting conditioned learning, through sensory cues, including aroma, touch and visual stimulation, to create perceptions of pending nicotine reward. This study examines the use of additives called ‘pyrazines’, which may enhance abuse potential, their introduction in ‘lights’ and subsequently in the highly market successful Marlboro Lights (Gold) cigarettes and eventually many major brands. Methods We conducted internal tobacco industry research using online databases in conjunction with published scientific literature research, based on an iterative feedback process. Results Tobacco manufacturers developed the use of a range of compounds, including pyrazines, in order to enhance ‘light’ cigarette products’ acceptance and sales. Pyrazines with chemosensory and pharmacological effects were incorporated in the first ‘full-flavour, low-tar’ product achieving high market success. Such additives may enhance dependence by helping to optimise nicotine delivery and dosing and through cueing and learned behaviour. Conclusions Cigarette additives and ingredients with chemosensory effects that promote addiction by acting synergistically with nicotine, increasing product appeal, easing smoking initiation, discouraging cessation or promoting relapse should be regulated by the US Food and Drug Administration. Current models of tobacco abuse liability could be revised to include more explicit roles with regard to non-nicotine constituents that enhance abuse potential. PMID:26063608

  13. A Mechanistic Study of Halogen Addition and Photoelimination from π-Conjugated Tellurophenes.

    PubMed

    Carrera, Elisa I; Lanterna, Anabel E; Lough, Alan J; Scaiano, Juan C; Seferos, Dwight S

    2016-03-01

    The ability to drive reactivity using visible light is of importance for many disciplines of chemistry and has significant implications for sustainable chemistry. Identifying photochemically active compounds and understanding photochemical mechanisms is important for the development of useful materials for synthesis and catalysis. Here we report a series of photoactive diphenyltellurophene compounds bearing electron-withdrawing and electron-donating substituents synthesized by alkyne coupling/ring closing or palladium-catalyzed ipso-arylation chemistry. The redox chemistry of these compounds was studied with respect to oxidative addition and photoelimination of bromine, which is of importance for energy storage reactions involving X2. The oxidative addition reaction mechanism was studied using density functional theory, the results of which support a three-step mechanism involving the formation of an initial η(1) association complex, a monobrominated intermediate, and finally the dibrominated product. All of the tellurophene derivatives undergo photoreduction using 430, 447, or 617 nm light depending on the absorption properties of the compound. Compounds bearing electron-withdrawing substituents have the highest photochemical quantum efficiencies in the presence of an alkene trap, with efficiencies of up to 42.4% for a pentafluorophenyl-functionalized tellurophene. The photoelimination reaction was studied in detail through bromine trapping experiments and laser flash photolysis, and a mechanism is proposed. The photoreaction, which occurs by release of bromine radicals, is competitive with intersystem crossing to the triplet state of the brominated species, as evidenced by the formation of singlet oxygen. These findings should be useful for the design of new photochemically active compounds supported by main-group elements. PMID:26853739

  14. Study of mandible reconstruction using a fibula flap with application of additive manufacturing technology

    PubMed Central

    2014-01-01

    Background This study aimed to establish surgical guiding techniques for completing mandible lesion resection and reconstruction of the mandible defect area with fibula sections in one surgery by applying additive manufacturing technology, which can reduce the surgical duration and enhance the surgical accuracy and success rate. Methods A computer assisted mandible reconstruction planning (CAMRP) program was used to calculate the optimal cutting length and number of fibula pieces and design the fixtures for mandible cutting, registration, and arrangement of the fibula segments. The mandible cutting and registering fixtures were then generated using an additive manufacturing system. The CAMRP calculated the optimal fibula cutting length and number of segments based on the location and length of the defective portion of the mandible. The mandible cutting jig was generated according to the boundary surface of the lesion resection on the mandible STL model. The fibular cutting fixture was based on the length of each segment, and the registered fixture was used to quickly arrange the fibula pieces into the shape of the defect area. In this study, the mandibular lesion was reconstructed using registered fibular sections in one step, and the method is very easy to perform. Results and conclusion The application of additive manufacturing technology provided customized models and the cutting fixtures and registered fixtures, which can improve the efficiency of clinical application. This study showed that the cutting fixture helped to rapidly complete lesion resection and fibula cutting, and the registered fixture enabled arrangement of the fibula pieces and allowed completion of the mandible reconstruction in a timely manner. Our method can overcome the disadvantages of traditional surgery, which requires a long and different course of treatment and is liable to cause error. With the help of optimal cutting planning by the CAMRP and the 3D printed mandible resection jig and

  15. Exploratory studies of extended storage of apheresis platelets in a platelet additive solution (PAS).

    PubMed

    Slichter, Sherrill J; Corson, Jill; Jones, Mary Kay; Christoffel, Todd; Pellham, Esther; Bailey, S Lawrence; Bolgiano, Doug

    2014-01-01

    To evaluate the poststorage viability of apheresis platelets stored for up to 18 days in 80% platelet additive solution (PAS)/20% plasma, 117 healthy subjects donated platelets using the Haemonetics MCS+, COBE Spectra (Spectra), or Trima Accel (Trima) systems. Control platelets from the same subjects were compared with their stored test PAS platelets by radiolabeling their stored and control platelets with either (51)chromium or (111)indium. Trima platelets met Food and Drug Administration poststorage platelet viability criteria for only 7 days vs almost 13 days for Haemonetics platelets; ie, platelet recoveries after these storage times averaged 44 ± 3% vs 49 ± 3% and survivals were 5.4 ± 0.3 vs 4.6 ± 0.3 days, respectively. The differences in storage duration are likely related to both the collection system and the storage bag. The Spectra and Trima platelets were hyperconcentrated during collection, and PAS was added, whereas the Haemonetics platelets were elutriated with PAS, which may have resulted in less collection injury. When Spectra and Trima platelets were stored in Haemonetics' bags, poststorage viability was significantly improved. Platelet viability is better maintained in vitro than in vivo, allowing substantial increases in platelet storage times. However, implementation will require resolution of potential bacterial overgrowth during storage. PMID:24258816

  16. Resources allocation in healthcare for cancer: a case study using generalised additive mixed models.

    PubMed

    Musio, Monica; Sauleau, Erik A; Augustin, Nicole H

    2012-11-01

    Our aim is to develop a method for helping resources re-allocation in healthcare linked to cancer, in order to replan the allocation of providers. Ageing of the population has a considerable impact on the use of health resources because aged people require more specialised medical care due notably to cancer. We propose a method useful to monitor changes of cancer incidence in space and time taking into account two age categories, according to healthcar general organisation. We use generalised additive mixed models with a Poisson response, according to the methodology presented in Wood, Generalised additive models: an introduction with R. Chapman and Hall/CRC, 2006. Besides one-dimensional smooth functions accounting for non-linear effects of covariates, the space-time interaction can be modelled using scale invariant smoothers. Incidence data collected by a general cancer registry between 1992 and 2007 in a specific area of France is studied. Our best model exhibits a strong increase of the incidence of cancer along time and an obvious spatial pattern for people more than 70 years with a higher incidence in the central band of the region. This is a strong argument for re-allocating resources for old people cancer care in this sub-region. PMID:23242683

  17. Covalent binding of aniline to humic substances. 2. 15N NMR studies of nucleophilic addition reactions

    USGS Publications Warehouse

    Thorn, K.A.; Pettigrew, P.J.; Goldenberg, W.S.; Weber, E.J.

    1996-01-01

    Aromatic amines are known to undergo covalent binding with humic substances in the environment. Although previous studies have examined reaction conditions and proposed mechanisms, there has been no direct spectroscopic evidence for the covalent binding of the amines to the functional groups in humic substances. In order to further elucidate the reaction mechanisms, the Suwannee River and IHSS soil fulvic and humic acids were reacted with 15N-labeled aniline at pH 6 and analyzed using 15N NMR spectrometry. Aniline underwent nucleophilic addition reactions with the quinone and other carbonyl groups in the samples and became incorporated in the form of anilinohydroquinone, anilinoquinone, anilide, imine, and heterocyclic nitrogen, the latter comprising 50% or more of the bound amine. The anilide and anilinohydroquinone nitrogens were determined to be susceptible to chemical exchange by ammonia. In the case of Suwannee River fulvic acid, reaction under anoxic conditions and pretreatment with sodium borohydride or hydroxylamine prior to reaction under oxic conditions resulted in a decrease in the proportion of anilinohydroquinone nitrogen incorporated. The relative decrease in the incorporation of anilinohydroquinone nitrogen with respect to anilinoquinone nitrogen under anoxic conditions suggested that inter- or intramolecular redox reactions accompanied the nucleophilic addition reactions.

  18. Toxicogenomics concepts and applications to study hepatic effects of food additives and chemicals

    SciTech Connect

    Stierum, Rob . E-mail: stierum@voeding.tno.nl; Heijne, Wilbert; Kienhuis, Anne; Ommen, Ben van; Groten, John

    2005-09-01

    Transcriptomics, proteomics and metabolomics are genomics technologies with great potential in toxicological sciences. Toxicogenomics involves the integration of conventional toxicological examinations with gene, protein or metabolite expression profiles. An overview together with selected examples of the possibilities of genomics in toxicology is given. The expectations raised by toxicogenomics are earlier and more sensitive detection of toxicity. Furthermore, toxicogenomics will provide a better understanding of the mechanism of toxicity and may facilitate the prediction of toxicity of unknown compounds. Mechanism-based markers of toxicity can be discovered and improved interspecies and in vitro-in vivo extrapolations will drive model developments in toxicology. Toxicological assessment of chemical mixtures will benefit from the new molecular biological tools. In our laboratory, toxicogenomics is predominantly applied for elucidation of mechanisms of action and discovery of novel pathway-supported mechanism-based markers of liver toxicity. In addition, we aim to integrate transcriptome, proteome and metabolome data, supported by bioinformatics to develop a systems biology approach for toxicology. Transcriptomics and proteomics studies on bromobenzene-mediated hepatotoxicity in the rat are discussed. Finally, an example is shown in which gene expression profiling together with conventional biochemistry led to the discovery of novel markers for the hepatic effects of the food additives butylated hydroxytoluene, curcumin, propyl gallate and thiabendazole.

  19. Assessment of Nano Cellulose from Peach Palm Residue as Potential Food Additive: Part II: Preliminary Studies.

    PubMed

    Andrade, Dayanne Regina Mendes; Mendonça, Márcia Helena; Helm, Cristiane Vieira; Magalhães, Washington L E; de Muniz, Graciela Ines Bonzon; Kestur, Satyanarayana G

    2015-09-01

    High consumption of dietary fibers in the diet is related to the reduction of the risk of non-transmitting of chronic diseases, prevention of the constipation etc. Rich diets in dietary fibers promote beneficial effects for the metabolism. Considering the above and recognizing the multifaceted advantages of nano materials, there have been many attempts in recent times to use the nano materials in the food sector including as food additive. However, whenever new product for human and animal consumption is developed, it has to be tested for their effectiveness regarding improvement in the health of consumers, safety aspects and side effects. However, before it is tried with human beings, normally such materials would be assessed through biological tests on a living organism to understand its effect on health condition of the consumer. Accordingly, based on the authors' finding reported in a previous paper, this paper presents body weight, biochemical (glucose, cholesterol and lipid profile in blood, analysis of feces) and histological tests carried out with biomass based cellulose nano fibrils prepared by the authors for its possible use as food additive. Preliminary results of the study with mice have clearly brought out potential of these fibers for the said purpose. PMID:26344977

  20. Comparative studies on nitrogen budgets of closed shrimp polyculture systems

    NASA Astrophysics Data System (ADS)

    Qi, Zhen-Xiong; Li, De-Shang; Zhang, Man-Ping; Dong, Shuang-Lin

    2001-09-01

    April to October, 1997 comparative studies on the nitrogen budgets of closed shrimp polyculture systems showed that, in all the studied polyculture systems, nitrogen from feeds and fertilizers were the main input items, which comprised 70.7% 83.9% of the total input nitrogen 3.2% 7.4% of which was provided by nitrogen fixation. It was in monoculture enclosures (Y-4, Y-11 and Y-12) that the percentage reached the maximum value. The output nitrogen in harvested products comprised 10.8% 24.6% of total input nitrogen, and the highest percentage, 24.6%, was found in shrimp-fish-tagelus polyculture systems. In shrimp monoculture and shrimp-fish polyculture systems, they were 19.1% and 21.9% respectively. The nitrogen utilization efficiency was different and varied from 12.2% was found in shrimp-tagelus polyculture systems. The lowest, 12.2%, was found in shrimp monoculture systems. All the nitrogen utilization efficiencies in shrimp-fish systems or shrimp-scallop systems seemed to be higher than that of the monoculture system, but they showed little statistical difference. The main outputs of nitrogen were found in sediment mud, and comprised 48.2% 60.8% of the total, input, the lowest percentage was found in shrimp-fish-tagelus polyculture systems, and the highest percentage in shrimp-scallop systems. During the experiment, nitrogen lost through denitrification and ammonia volatilization comprised 1.9% 6. 2%, averaged 2.8%, of the total input, and the loss through seepage comprised 5.9% 8.9% of the total. The estimated nitrogen attached to the enclosure wall comprised 3.7% 13.3% of the total, and was highest in shrimp monoculture systems. Compared with the classic shrimp farming industry, the closed shrimp polyculture systems may improve the nitrogen utilization efficiency, and hence reduce the environmental impacts on coastal waters. The nitrogen discharging rates for all the studied polyculture systems ranged from 3.0% to 6. 0% of total input nitrogen.

  1. Breast imaging with ultrasound tomography: a comparative study with MRI

    NASA Astrophysics Data System (ADS)

    Ranger, Bryan; Littrup, Peter; Duric, Neb; Li, Cuiping; Schmidt, Steven; Lupinacci, Jessica; Myc, Lukasz; Szczepanski, Amy; Rama, Olsi; Bey-Knight, Lisa

    2010-03-01

    The purpose of this study was to investigate the performance of an ultrasound tomography (UST) prototype relative to magnetic resonance (MR) for imaging overall breast anatomy and accentuating tumors relative to background tissue. The study was HIPAA compliant, approved by the Institutional Review Board, and performed after obtaining the requisite informed consent. Twenty-three patients were imaged with MR and the UST prototype. T1 weighted images with fat saturation, with and without gadolinium enhancement, were used to examine anatomical structures and tumors, while T2 weighted images were used to identify cysts. The UST scans generated sound speed, attenuation, and reflection images. A qualitative visual comparison of the MRI and UST images was then used to identify anatomical similarities. A more focused approach that involved a comparison of reported masses, lesion volumes, and breast density was used to quantify the findings from the visual assessment. Our acoustic tomography prototype imaged distributions of fibrous stroma, parenchyma, fatty tissues, and lesions in patterns similar to those seen in the MR images. The range of thresholds required to establish tumor volume equivalency between MRI and UST suggested that a universal threshold for isolating masses relative to background tissue is feasible with UST. UST has demonstrated the ability to visualize and characterize breast tissues in a manner comparable to MRI. Thresholding techniques accentuate masses relative to background anatomy, which may prove clinically useful for early cancer detection.

  2. Spatial Navigation Strategies in Peromyscus: a Comparative Study.

    PubMed

    Jašarević, Eldin; Williams, Scott A; Roberts, R Michael; Geary, David C; Rosenfeld, Cheryl S

    2012-11-01

    A male advantage in spatial abilities is predicted to evolve in species where males rely on expansion of home territory to locate dispersed mates during the breeding season. We sought to examine mechanistic underpinnings of this evolved trait by comparing spatial navigational abilities in two species of Peromyscus that employ widely different reproductive strategies. Males and females from outbred stocks of deer mice (P. maniculatus bairdii) in which males engage in territorial expansion and mate search and California mice (P. californicus insignis), in which males do not, were administered tasks that assessed spatial learning and memory, and activity and exploratory behaviours. The maze employed for these studies included four spatial cues that could be used to aid in locating 1 of 12 potential escape holes. As predicted, male deer mice outperformed conspecific females and California mice males in maze performance and memory, and this difference appeared to be due to extent to which animals used spatial cues to guide maze navigation. Consistent with territorial expansion as a component of competition for mates, male deer mice were more active and engaged in more exploratory and less anxiety-related behaviours than conspecific females and California mice males. The results have implications for understanding and studying the cognitive and behavioural mechanisms that have evolved through male-male competition that involves territorial expansion and mate search. PMID:23355748

  3. Pupil dilation using drops vs gel: a comparative study

    PubMed Central

    Moisseiev, E; Loberman, D; Zunz, E; Kesler, A; Loewenstein, A; Mandelblum, J

    2015-01-01

    Purpose To compare the efficacy in pupil dilation and degree of discomfort between topical instillation of mydriatic drops and gel. Methods The study included 60 patients with no previous ocular history of trauma and surgery. One eye was dilated with two drops (tropicamide 0.5% and phenylephrine 10%), and the other with one drop of gel (tropicamide 0.5%+phenylephrine 5%). Pupil size was measured by a Colvard pupillometer at baseline and 5, 15, 30, and 45 min following instillation. Pain upon instillation was measured by visual analog scale (VAS). Results There was no difference in pupil size at baseline. Use of the gel achieved greater mydriasis than drops (P=0.01), and was also associated with lower pain scores (P=0.003). In diabetic patients, pupil size was smaller at baseline and following instillation of drops and gel. Use of the gel achieved an even greater degree of pupil dilation in this subset of patients than drops (P=0.019). Conclusions Gel formulation achieved significantly greater pupil dilation than drops, despite a lower concentration of phenylephrine, and was also associated with significantly lower patient discomfort. This study is the first report of improved mydriatic efficacy in diabetic patients. PMID:25857606

  4. Spatial Navigation Strategies in Peromyscus: a Comparative Study

    PubMed Central

    Jašarević, Eldin; Williams, Scott A.; Roberts, R. Michael; Geary, David C.; Rosenfeld, Cheryl S.

    2012-01-01

    A male advantage in spatial abilities is predicted to evolve in species where males rely on expansion of home territory to locate dispersed mates during the breeding season. We sought to examine mechanistic underpinnings of this evolved trait by comparing spatial navigational abilities in two species of Peromyscus that employ widely different reproductive strategies. Males and females from outbred stocks of deer mice (P. maniculatus bairdii) in which males engage in territorial expansion and mate search and California mice (P. californicus insignis), in which males do not, were administered tasks that assessed spatial learning and memory, and activity and exploratory behaviours. The maze employed for these studies included four spatial cues that could be used to aid in locating 1 of 12 potential escape holes. As predicted, male deer mice outperformed conspecific females and California mice males in maze performance and memory, and this difference appeared to be due to extent to which animals used spatial cues to guide maze navigation. Consistent with territorial expansion as a component of competition for mates, male deer mice were more active and engaged in more exploratory and less anxiety-related behaviours than conspecific females and California mice males. The results have implications for understanding and studying the cognitive and behavioural mechanisms that have evolved through male-male competition that involves territorial expansion and mate search. PMID:23355748

  5. Comparative studies on the status of Indonesian coral reefs

    NASA Astrophysics Data System (ADS)

    Soekarno, R.

    Coral reefs are of great economic importance for Indonesia. Unfortunately these resources are suffering from increasing human pressure. Several factors may cause the degradation of coral reefs, including the consequences of several human activities. Activities indirectly affecting the quality of the reefs are land-based activities such as deforestation, agriculture intensification, industrialization and domestic waste disposal. Direct use of the reefs, e.g. by coral mining, fish blasting and other fishing and collecting activities, is of greater and more widespread importance. Therefore, a rational management of the reef resources is urgently needed. Management is impossible without simple means of monitoring the status of reefs. One factor, living coral cover, has been determined for several years in many areas, including those studied during the Snellius-II Expedition. This allowed a comparative study of several different areas, which showed that coral cover is often very useful as an indication of the quality of reefs. It was found that the diversity of reef fishes is correlated with the condition of reefs as determined by the percentage cover of living coral.

  6. Comparative study of biogenic and abiotic iron-containing materials

    NASA Astrophysics Data System (ADS)

    Cherkezova-Zheleva, Z.; Shopska, M.; Paneva, D.; Kovacheva, D.; Kadinov, G.; Mitov, I.

    2016-12-01

    Series of iron-based biogenic materials prepared by cultivation of Leptothrix group of bacteria in different feeding media ( Sphaerotilus-Leptothrix group of bacteria isolation medium, Adler, Lieske and silicon-iron-glucose-peptone) were studied. Control samples were obtained in the same conditions and procedures but the nutrition media were not infected with bacteria, i.e. they were sterile. Room and low temperature Mössbauer spectroscopy, powder X-ray diffraction (XRD), and infrared spectroscopy (IRS) were used to reveal the composition and physicochemical properties of biomass and respective control samples. Comparative analysis showed differences in their composition and dispersity of present phases. Sample composition included different ratio of nanodimensional iron oxyhydroxide and oxide phases. Relaxation phenomena such as superparamagnetism or collective magnetic excitation behaviour were registered for some of them. The experimental data showed that the biogenic materials were enriched in oxyhydroxides of high dispersion. Catalytic behaviour of a selected biomass and abiotic material were studied in the reaction of CO oxidation. In situ diffuse-reflectance (DR) IRS was used to monitor the phase transformations in the biomass and CO conversion.

  7. A comparative study of trained and untrained rabindrasangeet singers.

    PubMed

    Chatterjee, Indranil; Kumar, Suman; Chattopadhyay, Durba

    2012-12-01

    This scientific paper proposes an analytic framework specifically for Rabindrasangeet singing that models the time-varying physical and expressive characteristics unique to an individual voice through a phonetogram analysis. The present study incorporates the most popular Rabindrasangeet into account for analysis to get an idea about the specific numerical data regarding the fundamental frequency, semitones, SPL range, and area as well as to give a precise guideline to those clients. While comparing the trained and untrained singers both males and females the F0 parameter is found to be louder in trained group. The mean semitone is always higher in females than in males and the trained male subjects have significantly higher SPL range than trained female subjects and trained females have higher SPL range than untrained female subjects. The enclosed area is larger in trained singers and more in females than males. Results of this study indicate differences between untrained and trained phonetograms. These differences can be attributed to greater natural capacities in trainedsubjects or a superior learned control over the voice mechanism. PMID:24294579

  8. Comparative Study of Clinically Used NiTi Orthodontic Wires

    NASA Astrophysics Data System (ADS)

    Wang, Qiang; Zhang, Yang; Hao, Fengyu; Yang, Ke; Tan, Lili

    The purpose of the study was to comparatively investigate two NiTi orthodontic wires. It is valuable to determine the phase transformation temperature and corrosion characteristics of the orthodontic wires to further study the shape memory effect and corrosion resistance properties. Optical microscope and EDX analysis were used for microstructure characteristics and composition analysis. Differential scanning calorimetry (DSC) was carried out to identify the phase transformation behavior of the two wires. Electrochemical tests in artificial saliva at 37 ±1°C including polarization and electrochemical impedance spectroscopy (EIS) were used to assess the corrosion resistance and corrosion mechanism of the wires. It was found that the transformation temperature range of A-wire (imported) is narrower while the As and Af are close to the body temperature, which is more suitable in the orthodontic operation at early stage. The corrosion current density of A-wire is lower than that of B-wire (domestically made) while the corrosion potential is higher. EIS test results indicated that the corrosion mechanism was the same. However, the oxide layer formed on the surface of A-wire is more protective.

  9. Comparative study of analysis methods in biospeckle phenomenon

    NASA Astrophysics Data System (ADS)

    da Silva, Emerson Rodrigo; Muramatsu, Mikiya

    2008-04-01

    In this work we present a review of main statistical properties of speckle patterns and accomplish a comparative study of the more used methods for analysis and extraction of information from optical grainy. The first and second order space-time statistics are dicussed in an overview perspective. The biospeckle phenomenon has detailed attention, specially in its application on monitoring of activity in tissues. The main techniques used to obtain information from speckle patterns are presented, with special prominence to autocorrelation function, co-occurrence matrices, Fujii's method, Briers' contrast and spatial and temporal contrast analisys (LASCA and LASTCA). An incipient method for analysis, based on the study of sucessive correlations contrast, is introduced. Numerical simulations, using diferent probability density functions for velocities of scatterers, were made with two objectives: to test the analysis methods and to give subsidies for interpretation of in vivo results. Vegetable and animal tissues are investigated, achieving the monitoring of senescence process and vascularization maps on leaves, the accompaniment of fungi contamined fruits, the mapping of activity in flowers and the analisys of healing in rats subjected to abdominal surgery. Experiments using the biospeckle phenomenon in microscopy are carried out. At last, it is evaluated the potentiality of biospeckle as diagnosis tool in chronic vein ulcer cared with low intensity laser therapy and the better analysis methods for each kind of tissue are pointed.

  10. Comparative study of different surface decontaminants on chicken quality.

    PubMed

    Sinhamahapatra, M; Biswas, S; Das, A K; Bhattacharyya, D

    2004-10-01

    (1) A comparative study on the effect of different surface decontaminants: hot water at 70 degrees C for one minute; 2% lactic acid for 30 s; 1200 p.p.m. acidified sodium chlorite (ASC) solution for 5 s and 50 p.p.m. chlorine solution for 5 min in the form of dips and sprays on the surface of dressed broilers for 0, 24 and 48 h of storage was conducted. (2) The variables studied were, total plate count (TPC), presumptive coliform count (PCC), pH and extract release volume (ERV). All treatments reduced TPC and PCC. (3) Lactic acid dip and hot water dip were the most effective for reducing TPC (1.36 and 1.28 log/cm2, respectively) with no significant difference between them. (4) ASC and hot water in dip could diminish PCC (1.37 and 1.34 log/cm2, respectively) and did not vary significantly. (5) No treatment affected muscle pH, water holding capacity (WHC), ERV, appearance, smell, tenderness and overall acceptability of treated broilers significantly. (6) Hot water treatment is the cheapest, most convenient and simplest decontamination technique for hygienic and wholesome poultry production. PMID:15623215

  11. A comparative sealability study of different retrofilling materials.

    PubMed

    Ozata, F; Erdilek, N; Tezel, H

    1993-07-01

    The purpose of this study was to compare the sealing ability of high-copper amalgam, glass ionomer cement, and silver glass ionomer cement as retrofilling materials when used with and without varnish. Seventy extracted human single-rooted anterior teeth were instrumented and the root canals obturated with laterally condensed gutta-percha and sealer. The apical 3 mm of each root was resected and a 2 mm-deep apical Class I preparation cut. The roots were then randomly allocated to six groups of 10 teeth and retrofilled with one of the experiment materials. Group I comprised high-copper amalgam; group 2, high-copper amalgam with cavity varnish; group 3, glass ionomer cement without varnish; group 4, glass ionomer cement with varnish; group 5, silver glass ionomer cement without varnish; and group 6, silver glass ionomer cement with varnish. Two groups of five roots each were used as positive and negative controls. The root surfaces were coated with nail polish and specimens immersed in 2% methylene blue solution for 14 days. After vertical sectioning, dye penetration was examined under a stereomicroscope. The results of the study were analysed statistically. The sealing ability of the conventional glass ionomer cement with varnish was significantly better while dye penetration was higher in silver glass ionomer cement without varnish group than the other groups (P < 0.01). PMID:8225643

  12. A Comparative Study of Antifungal Activity of Endodontic Irrigants

    PubMed Central

    Mohammadi, Zahed; Asgary, Saeed

    2015-01-01

    Introduction: The purpose of this in vitro study was to assess the antifungal activity of final canal rinse with either three concentrations of sodium hypochlorite (NaOCl) (0.5, 2.6 and 6%), two concentrations of chlorhexidine (CHX) (2% and 0.2%), MTAD, Tetraclean, Hypoclean and Chlor-Xtra on Candida albicans (C. albicans) in a human tooth model. Methods and Materials: Two hundred and thirty five extracted human maxillary central and lateral incisors were used in this study. Teeth were randomly divided into nine test groups (n=25) and positive and a negative control groups (n=5). After cleaning and shaping, teeth were contaminated with C. albicans and incubated for 72 h. The irrigation solution in nine experimental groups included: 6% NaOCl, 2.6% NaOCl, 0.5% NaOCl, 2% CHX, 0.2% CHX, MTAD, Tetraclean, Hypoclean and Chlor-Xtra. After culturing on Sabouraud 4% dextrose agar, colony-forming units (CFU) were counted. Results: 6% NaOCl, 2% CHX and Chlor-Xtra were equally effective (P>0.05) and significantly superior to MTAD and Tetraclean (P<0.05). In addition, the effectiveness of Tetraclean and MTAD was significantly less than Hypoclean, NaOCl at all concentrations (6% 2.6% and 0.5%), MTAD and 0.2% CHX (P<0.05). Furthermore, Tetraclean was significantly more effective than MTAD (P<0.05). Conclusion: Antifungal activity of 6% NaOCl, Chlor-Xtra and 2% CHX was significantly greater than 2.6% NaOCl, 0.5% NaOCl, MTAD, 0.2% CHX and Tetraclean. PMID:25834602

  13. Traditional and accelerated Ponseti technique: a comparative study.

    PubMed

    Elgohary, Hatem S A; Abulsaad, Mazen

    2015-07-01

    The purpose of this study was to compare the results of traditional and accelerated Ponseti techniques to clarify whether this technique can be done safely in reduced time with complete correction of the deformity and without complications. A total of 66 feet in 41 children with idiopathic club foot and with Pirani score no <4 were included; of these, 34 feet in 20 children were managed with the traditional Ponseti method with one cast a week, in the other 32 feet in 21 children, an accelerated technique was used with casting twice a week, and the Pirani score was used for initial assessment and for follow-up. The results were comparable for both groups; the mean number of casts for full correction was 4.88 ± 0.88 in the traditional group and 5.16 ± 0.72 in the accelerated group. Initial correction was obtained in all cases in both groups, and relapses were observed in 14.7 % in the traditional group and in 15.6 % in the accelerated group. Deformities required from four to seven casts for correction in both groups. There was a statistically significant reduction in the mean time required for correction from onset of manipulation till tenotomy or correction of equines without tenotomy which was 33.36 ± 6.69 days (21-42 days) in the traditional Ponseti group and 18.13 ± 3.02 days (11-22 days) in accelerated Ponseti (P = 0.001). Accelerated Ponseti technique significantly reduces the correction time without affecting the final results; it is quite as safe and effective as the traditional Ponseti. PMID:25633123

  14. Mycobacterial species as case-study of comparative genome analysis.

    PubMed

    Zakham, F; Belayachi, L; Ussery, D; Akrim, M; Benjouad, A; El Aouad, R; Ennaji, M M

    2011-01-01

    The genus Mycobacterium represents more than 120 species including important pathogens of human and cause major public health problems and illnesses. Further, with more than 100 genome sequences from this genus, comparative genome analysis can provide new insights for better understanding the evolutionary events of these species and improving drugs, vaccines, and diagnostics tools for controlling Mycobacterial diseases. In this present study we aim to outline a comparative genome analysis of fourteen Mycobacterial genomes: M. avium subsp. paratuberculosis K—10, M. bovis AF2122/97, M. bovis BCG str. Pasteur 1173P2, M. leprae Br4923, M. marinum M, M. sp. KMS, M. sp. MCS, M. tuberculosis CDC1551, M. tuberculosis F11, M. tuberculosis H37Ra, M. tuberculosis H37Rv, M. tuberculosis KZN 1435 , M. ulcerans Agy99,and M. vanbaalenii PYR—1, For this purpose a comparison has been done based on their length of genomes, GC content, number of genes in different data bases (Genbank, Refseq, and Prodigal). The BLAST matrix of these genomes has been figured to give a lot of information about the similarity between species in a simple scheme. As a result of multiple genome analysis, the pan and core genome have been defined for twelve Mycobacterial species. We have also introduced the genome atlas of the reference strain M. tuberculosis H37Rv which can give a good overview of this genome. And for examining the phylogenetic relationships among these bacteria, a phylogenic tree has been constructed from 16S rRNA gene for tuberculosis and non tuberculosis Mycobacteria to understand the evolutionary events of these species. PMID:21396338

  15. Study on Friction and Wear Properties of Silver Matrix Brush Material with Different Additives

    NASA Astrophysics Data System (ADS)

    Chen, Xiaoli; Wang, Wenfang; Hong, Yu; Wu, Yucheng

    2013-07-01

    Friction and wear processes of AgCuX (G, CF and AlN) composites-CuAgV alloy friction pair and effects of different additive content in silver based composite on friction and wear behavior are studied in this paper. The microstructure of the brush wear surface is observed by SEM. The results show that when graphite content is up to 9 wt.%, Ag-Cu-CF-G composite exhibits the best wear properties; when the content of aluminum nitride is up to 0.5 wt.%, Ag-Cu-AlN-G composites has the most comprehensive performance. The wear loss of both composites arises with the increase of both pressure and speed, but when speed reaches a critical value, the increased amplitude of wear loss tends to be steady.

  16. Comparative Modeling Studies of Boreal Water and Carbon Balance

    NASA Technical Reports Server (NTRS)

    Coughlan, J.; Peterson, David L. (Technical Monitor)

    1997-01-01

    The coordination of the modeling and field efforts for an Intensive Field Campaign (IFC) may resemble the chicken and egg dilemma. This session's theme advocates that early and proactive involvement by modeling teams can produce a scientific and operational benefit for the IFC and Experiment. This talk will provide some examples and suggestions originating from the NASA funded IFC's of the FIFE First ISLSCP (International Satellite Land Surface Climatology Project) Field Experiment, Oregon Transect Ecosystem Research (OTTER) and predominately Boreal Ecosystem-Atmosphere Study (BOREAS) Experiments. In February 1994 and prior to the final selection of the BOREAS study sites, a group of funded BOREAS investigators agreed to run their models with data for five community types representing the proposed tower flux sites. All participating models were given identical initial values and boundary conditions and driven with identical climate data. The objectives of the intercomparison exercise were: 1) compare simulation results of participating terrestrial, hydrological, and atmospheric models over selected time frames; 2) learn about model behavior and sensitivity to estimated boreal site and vegetation definitions; 3) prioritize BOREAS field data collection efforts supporting modeling studies; 4) identify individual model deficiencies as early as possible. Out of these objectives evolved some important coordination and science issues for the BOREAS Experiment that can be generalized to IFCs and long term archiving of the data. Some problems are acceptable because they are endemic to maintaining fair and open competition prior to the peer review process. Others are logistical and addressable through application of planning, management, and information sciences. This investigator has identified one source of measurement and model incompatibility that is manifest in the IFC scaling approach. Although intuitively obvious, scaling problems are already more formally defined in

  17. Comparative study of the synthesis of layered transition metal molybdates

    SciTech Connect

    Mitchell, S.; Gomez-Aviles, A.; Gardner, C.; Jones, W.

    2010-01-15

    Mixed metal oxides (MMOs) prepared by the mild thermal decomposition of layered double hydroxides (LDHs) differ in their reactivity on exposure to aqueous molybdate containing solutions. In this study, we investigate the reactivity of some T-Al containing MMOs (T=Co, Ni, Cu or Zn) towards the formation of layered transition metal molybdates (LTMs) possessing the general formula AT{sub 2}(OH)(MoO{sub 4}){sub 2}.H{sub 2}O, where A=NH{sub 4}{sup +}, Na{sup +} or K{sup +}. The phase selectivity of the reaction was studied with respect to the source of molybdate, the ratio of T to Mo and the reaction pH. LTMs were obtained on reaction of Cu-Al and Zn-Al containing MMOs with aqueous solutions of ammonium heptamolybdate. Rehydration of these oxides in the presence of sodium or potassium molybdate yielded a rehydrated LDH phase as the only crystalline product. The LTM products obtained by the rehydration of MMO precursors were compared with LTMs prepared by direct precipitation from the metal salts in order to study the influence of preparative route on their chemical and physical properties. Differences were noted in the composition, morphology and thermal properties of the resulting products. - Graphical abstract: Mixed metal oxides (MMOs) derived from layered double hydroxide precursors differ in their reactivity on exposure to aqueous molybdate containing solutions. We investigate the influence of the molybdate source, the rehydration pH and the ratio of T/Mo on the reactivity of some T-Al containing MMOs (T=Co, Ni, Cu or Zn) towards the formation of layered transition metal molybdates of general formula AT{sub 2}(OH)(MoO{sub 4}){sub 2}.H{sub 2}O (where A{sup +}=NH{sub 4}{sup +}, K{sup +} or Na{sup +}).

  18. Mesiodistal odontometrics as a distinguishing trait: A comparative preliminary study

    PubMed Central

    Sravya, Taneeru; Dumpala, Rakesh Kumar; Guttikonda, Venkateswara Rao; Manchikatla, Praveen Kumar; Narasimha, Vanajakshi China

    2016-01-01

    Introduction: Sex determination is a vital step in reconstructing an individual profile from unidentified skeletal remnants. Variations in tooth size are influenced by genetic and environmental factors. Tooth size variations have been reported among different populations. Aim: To identify the sex by determining the mesiodistal (MD) dimensions of maxillary canines. Objectives: (1) To compare the MD diameter of all maxillary canines — (a) in the entire urban and tribal population, (b) in urban male and urban female populations, (c) in tribal male and tribal female populations, and (d) in the entire male and female populations and (2) To estimate the percentage of sexual dimorphism individually in urban and tribal populations. Materials and Methods: Fifty subjects each from urban and tribal populations in equal gender ratio were selected in Khammam district, Telangana, for the purpose of this study. After obtaining informed consent, maxillary study models of the selected subjects were made. MD diameters of left and right maxillary canines were measured on casts using vernier calipers. The obtained data were subjected to statistical analysis. Results: (1) The total tribal population showed a greater MD diameter of maxillary canines than the total urban population, (2) Urban males showed a greater MD diameter of maxillary canines than urban females, (3) Tribal males showed a greater MD diameter of maxillary canines than tribal females, (4) The entire male population showed a greater MD diameter of maxillary canines than the entire female population, and (5) The percentage of dimorphism between males and females in individual groups was found to be significant. Conclusion: The study showed maxillary canines exhibiting significant sexual dimorphism and can be used as a distinguishing trait for sex determination along with other procedures. PMID:27555727

  19. Genetic assessment of additional endophenotypes from the Consortium on the Genetics of Schizophrenia Family Study.

    PubMed

    Greenwood, Tiffany A; Lazzeroni, Laura C; Calkins, Monica E; Freedman, Robert; Green, Michael F; Gur, Raquel E; Gur, Ruben C; Light, Gregory A; Nuechterlein, Keith H; Olincy, Ann; Radant, Allen D; Seidman, Larry J; Siever, Larry J; Silverman, Jeremy M; Stone, William S; Sugar, Catherine A; Swerdlow, Neal R; Tsuang, Debby W; Tsuang, Ming T; Turetsky, Bruce I; Braff, David L

    2016-01-01

    The Consortium on the Genetics of Schizophrenia Family Study (COGS-1) has previously reported our efforts to characterize the genetic architecture of 12 primary endophenotypes for schizophrenia. We now report the characterization of 13 additional measures derived from the same endophenotype test paradigms in the COGS-1 families. Nine of the measures were found to discriminate between schizophrenia patients and controls, were significantly heritable (31 to 62%), and were sufficiently independent of previously assessed endophenotypes, demonstrating utility as additional endophenotypes. Genotyping via a custom array of 1536 SNPs from 94 candidate genes identified associations for CTNNA2, ERBB4, GRID1, GRID2, GRIK3, GRIK4, GRIN2B, NOS1AP, NRG1, and RELN across multiple endophenotypes. An experiment-wide p value of 0.003 suggested that the associations across all SNPs and endophenotypes collectively exceeded chance. Linkage analyses performed using a genome-wide SNP array further identified significant or suggestive linkage for six of the candidate endophenotypes, with several genes of interest located beneath the linkage peaks (e.g., CSMD1, DISC1, DLGAP2, GRIK2, GRIN3A, and SLC6A3). While the partial convergence of the association and linkage likely reflects differences in density of gene coverage provided by the distinct genotyping platforms, it is also likely an indication of the differential contribution of rare and common variants for some genes and methodological differences in detection ability. Still, many of the genes implicated by COGS through endophenotypes have been identified by independent studies of common, rare, and de novo variation in schizophrenia, all converging on a functional genetic network related to glutamatergic neurotransmission that warrants further investigation. PMID:26597662

  20. Comparative Climate Studies of Earth, Venus and Mars

    NASA Astrophysics Data System (ADS)

    Chassefiere, E.

    2008-12-01

    One of the most promising area in Solar System science is the comparative study of the three terrestrial planets (Venus, Earth, Mars). Why did the three planets evolve in such different ways, from relatively comparable initial states? The small size of Mars, favoring atmospheric escape, certainly played a role in making the present Mars so inhospitable. Venus has almost the same size and density as the Earth, and was probably initially endowed with similar amounts of volatile material. The absence of water in significant amounts on Venus, generally explained by intense primitive atmospheric escape, remains poorly constrained and understood. Two specific problems, related to Mars and Venus climate evolution, will be discussed in this talk. One major challenge of Mars studies is to determine the nature of the present Martian atmosphere: is it the residual of an old atmosphere, progressively lost by escape, or is it young, at steady state equilibrium between outgassing and escape? The possible detection of methane in Martian atmosphere suggests that methane currently is being produced, possibly signing outgassing, since methane is the thermodynamically favoured form of carbon, as released by potential volcanism or hydrothermalism, at low Martian temperature and pressure. Although no typical volcanic gas, like SO2, has ever been detected on Mars, the existence of recent lava flows (a few million years old) shows that a residual volcanism is still episodically active. Another possible tracer of outgassing, that is radon 222, seems promising, and could have been detected (although indirectly) in the Martian atmosphere from recent APXS (MER rovers) and Gamma Ray Spectrometer (Mars- Odyssey) measurements. The lack of any isotopic fractionation of carbon and oxygen in Martian CO2, as shown by existing measurements, suggests that the atmosphere of Mars is young, since it should have been fractionated by escape if it is old. This possibility of a young Martian atmosphere

  1. Study of triallyl phosphate as an electrolyte additive for high voltage lithium-ion cells

    NASA Astrophysics Data System (ADS)

    Xia, J.; Madec, L.; Ma, L.; Ellis, L. D.; Qiu, W.; Nelson, K. J.; Lu, Z.; Dahn, J. R.

    2015-11-01

    The role of triallyl phosphate as an electrolyte additive in Li(Ni0.42Mn0.42Co0.16)O2/graphite pouch cells was studied using ex-situ gas measurements, ultra high precision coulometry, automated storage experiments, electrochemical impedance spectroscopy, long-term cycling and X-ray photoelectron spectroscopy. Cells containing triallyl phosphate produced less gas during formation, cycling and storage than control cells. The use of triallyl phosphate led to higher coulombic efficiency and smaller charge endpoint capacity slippage during ultra high precision charger testing. Cells containing triallyl phosphate showed smaller potential drop during 500 h storage at 40 °C and 60 °C and the voltage drop decreased as the triallyl phosphate content in the electrolyte increased. However, large amounts of triallyl phosphate (>3% by weight in the electrolyte) led to large impedance after cycling and storage. Symmetric cell studies showed large amounts of triallyl phosphate (5% or more) led to significant impedance increase at both negative and positive electrodes. X-ray photoelectron spectroscopy studies suggested that the high impedance came from the polymerization of triallyl phosphate molecules which formed thick solid electrolyte interphase films at the surfaces of both negative and positive electrodes. An optimal amount of 2%-3% triallyl phosphate led to better capacity retention during long term cycling.

  2. No Additional Effect of DPP-4 Inhibitor on Preventing Atrial Fibrosis in Streptozotocin-Induced Diabetic Rat as Compared With Sulfonylurea.

    PubMed

    Hayami, Noriyuki; Sekiguchi, Akiko; Iwasaki, Yu-Ki; Murakawa, Yuji; Yamashita, Takeshi

    2016-05-25

    Chronic inflammation is known to occur in diabetes mellitus (DM) and contributes to atrial fibrosis, possible substrates for atrial fibrillation. We tested the hypothesis that dipeptidyl peptidase (DPP)-4 inhibitors prevent the formation of atrial fibrosis through their anti-inflammatory activity, beyond the effects of controlling blood glucose.DM models obtained by administration of streptozotocin (STZ) were divided into 3 groups: with PKF275-055, a DPP-4 inhibitor in group D, glibenclamide in group SU, and no additional drug in group P. At 8 weeks after STZ administration, the heart was subjected to Masson trichrome staining and immunohistochemistry with anti-ED2, ED3, and smooth muscle actin antibody.The % area of fibrosis in atria of group P accounted for 14.7% ± 4.1%, showing a significant increase in fibrosis when compared with the control group. In group SU, the % area accounted for 7.9% ± 2.9%, indicating significant deceased fibrosis by sulfonylurea. Meanwhile, we could not find significant differences in group D when compared to group P or group SU. While ED3-positive cells increased in group P (1.12% ± 0.24%), they were significantly decreased in groups D and SU (0.41% ± 0.22% and 0.55% ± 0.29%, respectively). Between group D and SU, however, there were no significant differences in the amount of cells positive to ED2, ED3, and smooth muscle actin antibodies.In STZ-induced DM rats, administration of sulfonylurea and DPP-4 inhibitors inhibited inflammation and fibrosis of the atria. However, no significant differences were observed between the 2 antidiabetic drugs. PMID:27149999

  3. Prefrontal cortex activity during motor tasks with additional mental load requiring attentional demand: a near-infrared spectroscopy study.

    PubMed

    Mandrick, Kevin; Derosiere, Gérard; Dray, Gérard; Coulon, Denis; Micallef, Jean-Paul; Perrey, Stéphane

    2013-07-01

    Functional near-infrared spectroscopy (fNIRS) is suitable for investigating cerebral oxygenation changes during motor and/or mental tasks. In the present study, we investigated how an additional mental load during a motor task at two submaximal loadings affects the fNIRS-measured brain activation over the right prefrontal cortex (PFC). Fifteen healthy males performed isometric grasping contractions at 15% and 30% of the maximal voluntary contraction (MVC) with or without an additional mental (i.e., arithmetic) task. Mental performance, force variability, fNIRS and subjective perception responses were measured in each condition. The performance of the mental task decreased significantly while the force variability increased significantly at 30% MVC as compared to 15% MVC, suggesting that performance of dual-task required more attentional resources. PFC activity increased significantly as the effort increased from 15% to 30% MVC (p<.001). Although a larger change in the deoxyhemoglobin was observed in dual-task conditions (p=.051), PFC activity did not change significantly as compared to the motor tasks alone. In summary, participants were unable to invest more attention and effort in performing the more difficult levels in order to maintain adequate mental performance. PMID:23665138

  4. Numerical study on the influence of hydrogen addition on soot formation in a laminar ethylene-air diffusion flame

    SciTech Connect

    Guo, Hongsheng; Liu, Fengshan; Smallwood, Gregory J.; Guelder, OEmer L.

    2006-04-15

    The influence of hydrogen addition to the fuel of an atmosphere pressure coflow laminar ethylene-air diffusion flame on soot formation was studied by numerical simulation. A detailed gas-phase reaction mechanism, which includes aromatic chemistry up to four rings, and complex thermal and transport properties were used. The fully coupled elliptic governing equations were solved. The interactions between soot and gas-phase chemistry were taken into account. Radiation heat transfer from CO{sub 2}, CO, H{sub 2}O, and soot was calculated using the discrete-ordinates method coupled to a statistical narrow-band-correlated K-based wide-band model. The predicted results were compared with the available experimental data and analyzed. It is indicated that the addition of hydrogen to the fuel in an ethylene-air diffusion flame suppresses soot formation through the effects of dilution and chemistry. This result is in agreement with available experiments. The simulations further suggest that the chemically inhibiting effect of hydrogen addition on soot formation is due to the decrease of hydrogen atom concentration in soot surface growth regions and higher concentration of molecular hydrogen in the lower flame region. (author)

  5. Scaling and Predictability in Stock Markets: A Comparative Study

    PubMed Central

    Zhang, Huishu; Wei, Jianrong; Huang, Jiping

    2014-01-01

    Most people who invest in stock markets want to be rich, thus, many technical methods have been created to beat the market. If one knows the predictability of the price series in different markets, it would be easier for him/her to make the technical analysis, at least to some extent. Here we use one of the most basic sold-and-bought trading strategies to establish the profit landscape, and then calculate the parameters to characterize the strength of predictability. According to the analysis of scaling of the profit landscape, we find that the Chinese individual stocks are harder to predict than US ones, and the individual stocks are harder to predict than indexes in both Chinese stock market and US stock market. Since the Chinese (US) stock market is a representative of emerging (developed) markets, our comparative study on the markets of these two countries is of potential value not only for conducting technical analysis, but also for understanding physical mechanisms of different kinds of markets in terms of scaling. PMID:24632944

  6. Scaling and predictability in stock markets: a comparative study.

    PubMed

    Zhang, Huishu; Wei, Jianrong; Huang, Jiping

    2014-01-01

    Most people who invest in stock markets want to be rich, thus, many technical methods have been created to beat the market. If one knows the predictability of the price series in different markets, it would be easier for him/her to make the technical analysis, at least to some extent. Here we use one of the most basic sold-and-bought trading strategies to establish the profit landscape, and then calculate the parameters to characterize the strength of predictability. According to the analysis of scaling of the profit landscape, we find that the Chinese individual stocks are harder to predict than US ones, and the individual stocks are harder to predict than indexes in both Chinese stock market and US stock market. Since the Chinese (US) stock market is a representative of emerging (developed) markets, our comparative study on the markets of these two countries is of potential value not only for conducting technical analysis, but also for understanding physical mechanisms of different kinds of markets in terms of scaling. PMID:24632944

  7. A framework for the comparative study of language.

    PubMed

    Uriagereka, Juan; Reggia, James A; Wilkinson, Gerald S

    2013-01-01

    Comparative studies of language are difficult because few language precursors are recognized. In this paper we propose a framework for designing experiments that test for structural and semantic patterns indicative of simple or complex grammars as originally described by Chomsky. We argue that a key issue is whether animals can recognize full recursion, which is the hallmark of context-free grammar. We discuss limitations of recent experiments that have attempted to address this issue, and point out that experiments aimed at detecting patterns that follow a Fibonacci series have advantages over other artificial context-free grammars. We also argue that experiments using complex sequences of behaviors could, in principle, provide evidence for fully recursive thought. Some of these ideas could also be approached using artificial life simulations, which have the potential to reveal the types of evolutionary transitions that could occur over time. Because the framework we propose has specific memory and computational requirements, future experiments could target candidate genes with the goal of revealing the genetic underpinnings of complex cognition. PMID:23864291

  8. Soft Tissue Phantoms for Realistic Needle Insertion: A Comparative Study.

    PubMed

    Leibinger, Alexander; Forte, Antonio E; Tan, Zhengchu; Oldfield, Matthew J; Beyrau, Frank; Dini, Daniele; Rodriguez Y Baena, Ferdinando

    2016-08-01

    Phantoms are common substitutes for soft tissues in biomechanical research and are usually tuned to match tissue properties using standard testing protocols at small strains. However, the response due to complex tool-tissue interactions can differ depending on the phantom and no comprehensive comparative study has been published to date, which could aid researchers to select suitable materials. In this work, gelatin, a common phantom in literature, and a composite hydrogel developed at Imperial College, were matched for mechanical stiffness to porcine brain, and the interactions during needle insertions within them were analyzed. Specifically, we examined insertion forces for brain and the phantoms; we also measured displacements and strains within the phantoms via a laser-based image correlation technique in combination with fluorescent beads. It is shown that the insertion forces for gelatin and brain agree closely, but that the composite hydrogel better mimics the viscous nature of soft tissue. Both materials match different characteristics of brain, but neither of them is a perfect substitute. Thus, when selecting a phantom material, both the soft tissue properties and the complex tool-tissue interactions arising during tissue manipulation should be taken into consideration. These conclusions are presented in tabular form to aid future selection. PMID:26666228

  9. Spheroid model study comparing the biocompatibility of Biodentine and MTA.

    PubMed

    Pérard, Matthieu; Le Clerc, Justine; Watrin, Tanguy; Meary, Fleur; Pérez, Fabienne; Tricot-Doleux, Sylvie; Pellen-Mussi, Pascal

    2013-06-01

    The primary objective of this study was to assess the biological effects of a new dentine substitute based on Ca₃SiO₅ (Biodentine™) for use in pulp-capping treatment, on pseudo-odontoblastic (MDPC-23) and pulp (Od-21) cells. The secondary objective was to evaluate the effects of Biodentine and mineral trioxide aggregate (MTA) on gene expression in cultured spheroids. We used the acid phosphatase assay to compare the biocompatibility of Biodentine and MTA. Cell differentiation was investigated by RT-qPCR. We investigated the expression of genes involved in odontogenic differentiation (Runx2), matrix secretion (Col1a1, Spp1) and mineralisation (Alp). ANOVA and PLSD tests were used for data analysis. MDPC-23 cells cultured in the presence of MTA had higher levels of viability than those cultured in the presence of Biodentine and control cells on day 7 (P = 0.0065 and P = 0.0126, respectively). For Od-21 cells, proliferation rates on day 7 were significantly lower in the presence of Biodentine or MTA than for control (P < 0.0001). Col1a1 expression levels were slightly lower in cells cultured in the presence of MTA than in those cultured in the presence of Biodentine and in control cells. Biodentine and MTA may modify the proliferation of pulp cell lines. Their effects may fluctuate over time, depending on the cell line considered. The observed similarity between Biodentine and MTA validates the indication for direct pulp-capping claimed by the manufacturers. PMID:23515903

  10. Frontotemporal Dementia in Southeast Asia: A Comparative Study

    PubMed Central

    Tan, Yee-Leng; Ng, Amanda; Kandiah, Nagaendran

    2013-01-01

    Background The clinical profile of frontotemporal dementia (FTD) in Southeast Asia is not known. We characterized and compared the demographic and clinical characteristics of FTD patients in Southeast Asia with North Asian and Western patients. Methods The study included Southeast Asian FTD patients presenting to a tertiary neurology institute. Behavioral variant (bv-FTD) and language variant (lv-FTD) subtypes of FTD were diagnosed based on the Lund-Manchester criteria. The patients were characterized according to demographics, clinical, neuroimaging and longitudinal profiles. Results Twenty-five bv-FTD and 19 lv-FTD patients were identified, with a female predominance ratio of 2:1 and a mean age of 56 years. The mean MMSE score was 16.2, and 88.4% of patients had memory symptoms. Over 5.1 ± 2.4 years of follow-up, 60% of bv-FTD and 36.8% of lv-FTD patients developed a second FTD syndrome. bv-FTD was the predominant type of FTD among Southeast Asians. Conclusion FTD represents an important cause of young-onset dementia in Southeast Asia. Greater awareness of FTD is required to ensure early diagnosis and management. PMID:23569453

  11. A comparative study of prebiotic and present day translational models

    NASA Technical Reports Server (NTRS)

    Rein, R.; Raghunathan, G.; Mcdonald, J.; Shibata, M.; Srinivasan, S.

    1986-01-01

    It is generally recognized that the understanding of the molecular basis of primitive translation is a fundamental step in developing a theory of the origin of life. However, even in modern molecular biology, the mechanism for the decoding of messenger RNA triplet codons into an amino acid sequence of a protein on the ribosome is understood incompletely. Most of the proposed models for prebiotic translation lack, not only experimental support, but also a careful theoretical scrutiny of their compatibility with well understood stereochemical and energetic principles of nucleic acid structure, molecular recognition principles, and the chemistry of peptide bond formation. Present studies are concerned with comparative structural modelling and mechanistic simulation of the decoding apparatus ranging from those proposed for prebiotic conditions to the ones involved in modern biology. Any primitive decoding machinery based on nucleic acids and proteins, and most likely the modern day system, has to satisfy certain geometrical constraints. The charged amino acyl and the peptidyl termini of successive adaptors have to be adjacent in space in order to satisfy the stereochemical requirements for amide bond formation. Simultaneously, the same adaptors have to recognize successive codons on the messenger. This translational complex has to be realized by components that obey nucleic acid conformational principles, stabilities, and specificities. This generalized condition greatly restricts the number of acceptable adaptor structures.

  12. Osseointegration of alumina bioceramic granules: A comparative experimental study

    NASA Astrophysics Data System (ADS)

    Rerikh, V. V.; Avetisyan, A. R.; Zaydman, A. M.; Anikin, K. A.; Bataev, V. A.; Nikulina, A. A.; Sadovoy, M. A.; Aronov, A. M.; Semantsova, E. S.

    2016-08-01

    To perform a comparative analysis of osseointegration of bioceramic alumina-based granules, hydroxyapatite-based granules, and deproteinized bone granules. The experiment was conducted on 52 adult male Kyoto-Wistar rats weighing 350 to 520 g. The animals were divided into five matched groups that differed only in the type of an implanted material. The granules were implanted in the lumbar vertebral bodies and in the distal right femur of each laboratory animal. Two months after surgery, the animals were euthanized, followed by tissue sampling for morphological studies. An examination of specimens from the groups with implanted alumina granules revealed the newly formed trabecular bone with remodeling signs. The bone tissue filled the intragranular space, tightly adhering to the granule surface. There was no connective tissue capsule on the border between bone tissue and alumina granules. Cylindrical bioceramic alumina-based granules with an open internal channel have a higher strength surpassing than that of analogs and the osseointegration ability close to that of hydroxyapatite and deproteinized bone granules.

  13. Comparative Study Between Wind and Photovoltaic (PV) Systems

    NASA Astrophysics Data System (ADS)

    Taha, Wesam

    This paper reviews two renewable energy systems; wind and photovoltaic (PV) systems. The common debate between the two of them is to conclude which one is better, in terms of cost and efficiency. Therefore, comparative study, in terms of cost and efficiency, is attempted. Regarding total cost of both, wind and PV systems, many parameters must be taken into consideration such as availability of energy (either wind or solar), operation and maintenance, availability of costumers, political influence, and the components used in building the system. The main components and parameters that play major role in determining the overall efficiency of wind systems are the wind turbine generator (WTG), gearbox and control technologies such as power, and speed control. On the other hand, in grid-connected PV systems (GCPVS), converter architecture along with maximum power point tracking (MPPT) algorithm and inverter topologies are the issues that affects the efficiency significantly. Cost and efficiency analyses of both systems have been carried out based on the statistics available till today and would be useful in the progress of renewable energy penetration throughout the world.

  14. Fungal biodegradation of anthracene-polluted cork: A comparative study.

    PubMed

    Jové, Patrícia; Olivella, Maria À; Camarero, Susana; Caixach, Josep; Planas, Carles; Cano, Laura; De Las Heras, Francesc X

    2016-01-01

    The efficiency of cork waste in adsorbing aqueous polycyclic aromatic hydrocarbons (PAHs) has been previously reported. Biodegradation of contaminated cork using filamentous fungi could be a good alternative for detoxifying cork to facilitate its final processing. For this purpose, the degradation efficiency of anthracene by three ligninolytic white-rot fungi (Phanerochaete chrysosporium, Irpex lacteus and Pleurotus ostreatus) and three non-ligninolytic fungi which are found in the cork itself (Aspergillus niger, Penicillium simplicissimum and Mucor racemosus) are compared. Anthracene degradation by all fungi was examined in solid-phase cultures after 0, 16, 30 and 61 days. The degradation products of anthracene by P. simplicissimum and I. lacteus were also identified by GC-MS and a metabolic pathway was proposed for P. simplicissimum. Results show that all the fungi tested degraded anthracene. After 61 days of incubation, approximately 86%, 40%, and 38% of the initial concentration of anthracene (i.e., 100 µM) was degraded by P. simplicissimum, P. chrysosporium and I. lacteus, respectively. The rest of the fungi degraded anthracene to a lesser extent (<30%). As a final remark, the results obtained in this study indicate that P. simplicissimum, a non-ligninolytic fungi characteristic of cork itself, could be used as an efficient degrader of PAH-contaminated cork. PMID:26540209

  15. Comparative Case Study of Two Biomedical Research Collaboratories

    PubMed Central

    Teasley, Stephanie D; Bhatnagar, Rishi

    2005-01-01

    Background Working together efficiently and effectively presents a significant challenge in large-scale, complex, interdisciplinary research projects. Collaboratories are a nascent method to help meet this challenge. However, formal collaboratories in biomedical research centers are the exception rather than the rule. Objective The main purpose of this paper is to compare and describe two collaboratories that used off-the-shelf tools and relatively modest resources to support the scientific activity of two biomedical research centers. The two centers were the Great Lakes Regional Center for AIDS Research (HIV/AIDS Center) and the New York University Oral Cancer Research for Adolescent and Adult Health Promotion Center (Oral Cancer Center). Methods In each collaboratory, we used semistructured interviews, surveys, and contextual inquiry to assess user needs and define the technology requirements. We evaluated and selected commercial software applications by comparing their feature sets with requirements and then pilot-testing the applications. Local and remote support staff cooperated in the implementation and end user training for the collaborative tools. Collaboratory staff evaluated each implementation by analyzing utilization data, administering user surveys, and functioning as participant observers. Results The HIV/AIDS Center primarily required real-time interaction for developing projects and attracting new participants to the center; the Oral Cancer Center, on the other hand, mainly needed tools to support distributed and asynchronous work in small research groups. The HIV/AIDS Center’s collaboratory included a center-wide website that also served as the launch point for collaboratory applications, such as NetMeeting, Timbuktu Conference, PlaceWare Auditorium, and iVisit. The collaboratory of the Oral Cancer Center used Groove and Genesys Web conferencing. The HIV/AIDS Center was successful in attracting new scientists to HIV/AIDS research, and members

  16. Comparative bioequivalence study of three formulations of enrofloxacin in sheep.

    PubMed

    El-Banna, H A; Goudah, A; El-Zorba, H

    2011-04-01

    A comparative pharmacokinetic study of three enrofloxacin injectable solutions was carried out in six healthy Barky rams after intramuscular injection according to a single dose, randomized, crossover experimental design. The three formulations were enrofloxacin 10% (Baytril(®)), enrofloxacin 10% plus bromhexine 1% (Mucotryl(®)) and enrofloxacin 10 % solution without bromhexine (Mucotryl without bromhexine). The three formulations were given a single intramuscular dose at a dose rate of 5 mg kg(-1) b.wt. The concentrations of the drug in the serum were measured using high-performance liquid chromatography (HPLC) with fluorescence detection. The results indicate that there were no significant differences between the distribution rate constant (k(ab)) and distribution half-life (t(1/2ab)), the maximum serum concentration (C(max)) and the time to peak concentration (T(max)) between Baytril and the other two formulations. There were significant differences between the elimination half life (t(1/2el)) and elimination rate constant (k(el)), for Baytril and enrofloxacin (the exact formulation of Mucotryl without bromhexine). Enrofloxacin was rapidly absorbed following IM administration of 5 mg kg(-1) b. wt. The peak serum concentrations (C(max)) were 2.83, 2.45 and 3.12 µg ml(-1) and were attained at (t(max)) 1.15, 1.41 and 1.26 hours when given Mucotryl, Baytril and enrofloxacin (the exact formulation of Mucotryl without bromhexine) to sheep, respectively. The injectable formulations investigated were bioequivalent after their intramuscular injection to sheep at recommended dose rate. As our results showed that, values of T(max), C(max) and AUC (Area under time curve concentration) determined for both Baytril, Mucotryl, and enrofloxacin (the exact formulation of Mucotryl without bromhexine ( reference ant test products) are within the acceptable range of 0.80-1.20, this means that the tested products product under investigation was bio-equivalent. These findings

  17. Experimental Study of Disruption of Columnar Grains During Rapid Solidification in Additive Manufacturing

    NASA Astrophysics Data System (ADS)

    Manogharan, Guha; Yelamanchi, Bharat; Aman, Ronald; Mahbooba, Zaynab

    2016-03-01

    Over the years, many studies have been conducted to study and analyze the grain structures of metal alloys during additive manufacturing to improve mechanical properties. In particular, columnar grains are observed predominantly during rapid solidification of molten metal. This leads to lower mechanical properties and requires expensive secondary heat-treatment processes. This study is aimed at disrupting the formation of columnar grain growth during rapid solidification using ultrasonic vibration and analyzes the effects on grain structure and mechanical properties. A gas-metal arc welder mounted on a Rep-Rap-based low-cost metal 3 Dimension printer was used to deposit ER70S-6 mild steel layers on a plate. A contact-type ultrasonic transducer with a control system to vary the frequency and power of the vibration was used. The effects of ultrasonic vibration were determined from the statistical analysis of microstructure and micro-indentation techniques on the deposited layer and heat-affected zone. It was found that both frequency and interaction between frequency and power had significant impact on the refinement of average grain size up to 10.64% and increased the number of grains by approximately 41.78%. Analysis of micro-indentation tests showed that there was an increase of approximately 14.30% in micro-hardness due to the applied frequency during rapid solidification. A pole diagram shows that application of vibration causes randomization of grain orientation. Along with the results from this study, further efforts in modeling and experimentation of multi-directional vibrations would lead to a better understanding of disrupting columnar grains in applications that use mechanical vibrations, such as welding, directed energy deposition, brazing, etc.

  18. Synthesis, Characterization, Molecular Modeling, and DNA Interaction Studies of Copper Complex Containing Food Additive Carmoisine Dye.

    PubMed

    Shahabadi, Nahid; Akbari, Alireza; Jamshidbeigi, Mina; Khodarahmi, Reza

    2016-06-01

    A copper complex of carmoisine dye; [Cu(carmoisine)2(H2O)2]; was synthesized and characterized by using physico-chemical and spectroscopic methods. The binding of this complex with calf thymus (ct) DNA was investigated by circular dichroism, absorption studies, emission spectroscopy, and viscosity measurements. UV-vis results confirmed that the Cu complex interacted with DNA to form a ground-state complex and the observed binding constant (2× 10(4) M(-1)) is more in keeping with the groove bindings with DNA. Furthermore, the viscosity measurement result showed that the addition of complex causes no significant change on DNA viscosity and it indicated that the intercalation mode is ruled out. The thermodynamic parameters are calculated by van't Hoff equation, which demonstrated that hydrogen bonds and van der Waals interactions played major roles in the reaction. The results of circular dichroism (CD) suggested that the complex can change the conformation of DNA from B-like form toward A-like conformation. The cytotoxicity studies of the carmoisine dye and its copper complex indicated that both of them had anticancer effects on HT-29 (colon cancer) cell line and they may be new candidates for treatment of the colon cancer. PMID:27152751

  19. Percutaneous Dorsal Instrumentation of Vertebral Burst Fractures: Value of Additional Percutaneous Intravertebral Reposition—Cadaver Study

    PubMed Central

    Krüger, Antonio; Schmuck, Maya; Noriega, David C.; Ruchholtz, Steffen; Baroud, Gamal; Oberkircher, Ludwig

    2015-01-01

    Purpose. The treatment of vertebral burst fractures is still controversial. The aim of the study is to evaluate the purpose of additional percutaneous intravertebral reduction when combined with dorsal instrumentation. Methods. In this biomechanical cadaver study twenty-eight spine segments (T11-L3) were used (male donors, mean age 64.9 ± 6.5 years). Burst fractures of L1 were generated using a standardised protocol. After fracture all spines were allocated to four similar groups and randomised according to surgical techniques (posterior instrumentation; posterior instrumentation + intravertebral reduction device + cement augmentation; posterior instrumentation + intravertebral reduction device without cement; and intravertebral reduction device + cement augmentation). After treatment, 100000 cycles (100–600 N, 3 Hz) were applied using a servohydraulic loading frame. Results. Overall anatomical restoration was better in all groups where the intravertebral reduction device was used (p < 0.05). In particular, it was possible to restore central endplates (p > 0.05). All techniques decreased narrowing of the spinal canal. After loading, clearance could be maintained in all groups fitted with the intravertebral reduction device. Narrowing increased in the group treated with dorsal instrumentation. Conclusions. For height and anatomical restoration, the combination of an intravertebral reduction device with dorsal instrumentation showed significantly better results than sole dorsal instrumentation. PMID:26137481

  20. Density functional theory study of the effects of alloying additions on sulfur adsorption on nickel surfaces

    NASA Astrophysics Data System (ADS)

    Malyi, Oleksandr I.; Chen, Zhong; Kulish, Vadym V.; Bai, Kewu; Wu, Ping

    2013-01-01

    Reactions of hydrogen sulfide (H2S) with Nickel/Ytrria-doped zirconia (Ni/YDZ) anode materials might cause degradation of the performance of solid oxide fuel cells when S containing fuels are used. In this paper, we employ density functional theory to investigate S adsorption on metal (M)-doped and undoped Ni(0 0 1) and Ni(1 1 1) surfaces. Based on the performed calculations, we analyze the effects of 12 alloying additions (Ag, Au, Al, Bi, Cd, Co, Cu, Fe, Sn, Sb, V, and Zn) on the temperature of transition between clean (S atoms do not adsorb on the surfaces) and contaminated (S atoms can adsorb on the surfaces spontaneously) M-doped Ni surfaces for different concentrations of H2S in the fuel. Predicted results are consistent with many experimental studies relevant to S poisoning of both Ni/YDZ and M-doped Ni/YDZ anode materials. This study is important to understand S poisoning phenomena and to develop new S tolerant anode materials.

  1. Modeller's attitude in catchment modelling: a comparative study

    NASA Astrophysics Data System (ADS)

    Battista Chirico, Giovanni

    2010-05-01

    Ten modellers have been invited to predict, independently from each other, the discharge of the artificial Chicken Creek catchment in North-East Germany for simulation period of three years, providing them only soil texture, terrain and meteorological data. No data concerning the discharge or other sources of state variables and fluxes within the catchment have been provided. Modellers had however the opportunity to visit the experimental catchment and inspect areal photos of the catchments since its initial development stage. This study has been a unique comparative study focussing on how different modellers deal with the key issues in predicting the discharge in ungauged catchments: 1) choice of the model structure; 2) identification of model parameters; 3) identification of model initial and boundary conditions. The first general lesson learned during this study was that the modeller is just part of the entire modelling process and has a major bearing on the model results, particularly in ungauged catchments where there are more degrees of freedom in making modelling decisions. Modellers' attitudes during the stages of the model implementation and parameterisation have been deeply influenced by their own experience from previous modelling studies. A common outcome was that modellers have been mainly oriented to apply process-based models able to exploit the available data concerning the physical properties of the catchment and therefore could be more suitable to cope with the lack of data concerning state variables or fluxes. The second general lesson learned during this study was the role of dominant processes. We believed that the modelling task would have been much easier in an artificial catchment, where heterogeneity were expected to be negligible and processes simpler, than in catchments that have evolved over a longer time period. The results of the models were expected to converge, and this would have been a good starting point to proceed for a model

  2. Using laser diagnostics for studying the injection of a dry additive

    NASA Astrophysics Data System (ADS)

    Tokunov, Iu. M.; Zhilin, V. G.; Liuliukin, V. I.; Mostinskii, I. L.; Putin, Iu. A.

    1987-02-01

    In MHD generators using an ionizing additive, the uniform injection of the additive into the combustion chamber and the dispersity of the injected particles are important. Some of the problems associated with the injection of an ionizing additive can be alleviated by using dry additives. In the experiment reported here, an He-Ne laser was used to monitor the injection of potash powder with an average size of 40 microns. It is shown that laser diagnostics can be successfully used to determine the mean particle diameter and variation of the powder flow rate with time.

  3. Evaluation of additional head of biceps brachii: a study with autopsy material.

    PubMed

    Ballesteros, L E; Forero, P L; Buitrago, E R

    2014-05-01

    Additional head of the biceps brachii (AHBB) has been reported in different population groups with a frequency of 1-25%. The purpose of this study was to determine the incidence and morphologic expression of the AHBB as determined in a sample of the Colombian population. An exploration was conducted with 106 arms corresponding to unclaimed corpses autopsied at Institute of Legal and Forensic Medicine of Bucaramanga, Colombia. Using medial incision involvingskin, subcutaneous tissue, and brachial fascia, the heads of the biceps and their innervating branches were visualised. One AHBB was observed in 21 (19.8%) of the arms evaluated, with non-significant difference (p = 0.568) per side of presentation: 11 (52.4%) cases on the right side and 10 (47.6%) on the left side. All AHBBs were originated in the infero-medial segment of the humerus, with a mean thickness of 17.8 ± 6.8 mm. In 4 (19%) cases the fascicle was thin, less than 10 mm; in 7 (33.3%) cases it was of medium thickness, between 11 and 20 mm, whereas in 47.6% it was longer than 20 mm. The length of the AHBB was 118.3 ± 26.8 mm; its motor point supplied by the musculocutaneous nerve was located at 101.3 ± 20.9 mm of the bi-epicondylar line. The incidence of AHBB in this study is located at the upper segment of what has been reportedin the literature and could be a morphologic trait of the Colombian population; in agreement with prior studies, the origin was the infero-medial surface of the humerus. PMID:24902098

  4. Does interprofessional simulation increase self-efficacy: a comparative study

    PubMed Central

    Watters, Colm; Reedy, Gabriel; Ross, Alastair; Morgan, Nicola J; Handslip, Rhodri; Jaye, Peter

    2015-01-01

    Objectives In this work, we have compared uniprofessional and interprofessional versions of a simulation education intervention, in an attempt to understand more about whether it improves trainees’ self-efficacy. Background Interprofessionalism has been climbing the healthcare agenda for over 50 years. Simulation education attempts to create an environment for healthcare professionals to learn, without potential safety risks for patients. Integrating simulation and interprofessional education can provide benefits to individual learners. Setting The intervention took place in a high-fidelity simulation facility located on the campus of a large urban hospital. The centre provides educational activities for an Academic Health Sciences Centre. Approximately 2500 staff are trained at the centre each year. Participants One hundred and fifteen nurses and midwives along with 156 doctors, all within the early years of their postgraduate experience participated. All were included on the basis of their ongoing postgraduate education. Methods Each course was a one-day simulation course incorporating five clinical and one communication scenarios. After each a facilitated debriefing took place. A mixed methods approach utilised precourse and postcourse questionnaires measuring self-efficacy in managing emergency situations, communication, teamwork and leadership. Results Thematic analysis of qualitative data showed improvements in communication/teamwork and leadership, for doctors and nurses undergoing simulation training. These findings were confirmed by statistical analysis showing that confidence ratings improved in nurses and doctors overall (p<0.001). Improved outcomes from baseline were observed for interprofessional versus uniprofessional trained nurses (n=115; p<0.001). Postcourse ratings for doctors showed that interprofessional training was significantly associated with better final outcomes for a communication/teamwork dimension (n=156; p<0.05). Conclusions This

  5. Comparative study of novel endovascular treatment techniques for intracranial aneurysms

    NASA Astrophysics Data System (ADS)

    Cantón, Gádor; Lasheras, Juan C.; Levy, David I.; Sparks, Steven R.

    2002-11-01

    Intracranial aneurysms are life-threatening vascular lesions, which are potentially treatable to avoid the consequences of their rupture. Current treatments, either surgical or endovascular, are all guided to reduce the hemodynamic forces acting on the aneurysm wall in an effort to minimize the risk of rupture. Surgical clipping is still the most used technique to treat this type of aneurysm but there is a continued demand for less invasive approaches. This has led to the development of several endovascular techniques. We report here a comparative study of the reduction in the hemodynamic stresses and the modification of the flow in the parent vessel resulting from the use of three different techniques. The first one consists of endosaccular packing with platinum coils (GDC, Target Therapeutics), which is already widely used but its long-term efficacy has not yet been determined. The second one consists of the embolization of the aneurismal sac with Onyx, a polymer which hardens when in contact with the blood (being developed by Micro Therapeutics, Inc.). The third one involves the packing of the sac with hydrocoils, platinum wires coated with a gel which quickly hydrates when in contact with blood (developed by MicroVention). A Digital Particle Image Velocimetry (DPIV) system is used to measure in vitro the velocity field inside a model of an ACOM aneurysm (an aneurysm forming in the anterior communicating artery). Physiological accurate pulsatile flow conditions are input to the arterial model through a programmable pump. The measurements show that although all treatment techniques lead to a reduction in both normal and tangential shear stresses on the aneurismal sac, each one of them also leads to different modifications of the flow in the parent vessel which may have consequences related to potential for clotting. Comparison of the untreated aneurysm with the above three treated cases also showed that the characteristics of the wall shear stresses on the parent

  6. Comparative Study of Non-Enveloped Icosahedral Viruses Size

    PubMed Central

    Nikitin, Nikolai; Trifonova, Ekaterina; Evtushenko, Evgeniy; Kirpichnikov, Mikhail; Atabekov, Joseph; Karpova, Olga

    2015-01-01

    Now, as before, transmission electron microscopy (TEM) is a widely used technique for the determination of virions size. In some studies, dynamic light scattering (DLS) has also been applied for this purpose. Data obtained by different authors and using different methods could vary significantly. The process of TEM sample preparation involves drying on the substrate, which can cause virions to undergo morphology changes. Therefore, other techniques should be used for measurements of virions size in liquid, (i.e. under conditions closer to native). DLS and nanoparticle tracking analysis (NTA) provide supplementary data about the virions hydrodynamic diameter and aggregation state in liquid. In contrast to DLS, NTA data have a higher resolution and also are less sensitive to minor admixtures. In the present work, the size of non-enveloped icosahedral viruses of different nature was analyzed by TEM, DLS and NTA: the viruses used were the encephalomyocarditis virus (animal virus), and cauliflower mosaic virus, brome mosaic virus and bean mild mosaic virus (plant viruses). The same, freshly purified, samples of each virus were used for analysis using the different techniques. The results were compared with earlier published data and description databases. DLS data about the hydrodynamic diameter of bean mild mosaic virus, and NTA data for all examined viruses, were obtained for the first time. For all virus samples, the values of size obtained by TEM were less than virions sizes determined by DLS and NTA. The contribution of the electrical double layer (EDL) in virions hydrodynamic diameter was evaluated. DLS and NTA data adjusted for EDL thickness were in better agreement with TEM results. PMID:26545232

  7. Comparative study on Kasisa Bhasma prepared by two different methods

    PubMed Central

    Rajput, Dhirajsingh; Tekale, G. S.; Patgiri, BJ

    2011-01-01

    Preparation of bhasma (calcined powder of metal/minerals) includes various processing steps like purification (Shodhana), levigation (Bhavana),calcinations cycle(Marana), improving quality and removing blemishes (Amritikarana) etc, processing of bhasma aims at formation of herbo-mineral complex molecule which can act in minimal dosage, palatable, easy for assimilation, highly efficacious with minimal or no complication. Although the most important equipment mentioned for Marana i.e. cow dung cakes and some type of woods are not only difficult to collect but also expensive and create pollution during puta and it's difficult task to give controlled heat in traditional method. Hence, a Modified Portable Bhasma Nirman Yantra (MPBNY) was prepared for puta (equipment for calcination) procedure which is easy to handle, portable and facilitate to supply controlled heat. A comparative study was conducted on Kasisa Bhasma prepared by traditional method and by using MPBNY with special reference to physico-chemical properties. The prepared Kasisa Bhasma was subjected to modern analytical parameters such as A.A.S. (Atomic Absorption Spectroscopy), X.R.D. (X-ray Diffraction) and Ayurvedic parameters eg. Rekhapurnatva (bhasma should enters in between lines of finger), Varitaratva (bhasma should float on the surface of water), Niramlatva (bitter less), Apunarbhava (bhasma should not regain its metallic nature after strong heating with jiggery, Abrus precatorius linn., honey and ghee) and Niruttha (bhasma should not regain its metallic nature after strong heating with silver). It was observed that Kasisa Bhasma of both methods possesses similar organoleptic as well as physico-chemical properties. PMID:23284208

  8. Impact comparative study of phone carcasses behavior by FEM

    NASA Astrophysics Data System (ADS)

    Constantin, Cărăuşu; Plăvănescu, Simona; Dumitru, Nedelcu

    2015-07-01

    A constant concern of scientific research is based on plastics replace with biodegradable materials that reduce the adverse impact of waste on the environment. A biodegradable material that arouses interest lately is Arboform which is made of lignin, a component of wood and woody plants. Replacing plastic with Arboform in carrying components of products requires technical and economic studies on the implications of such replacement. Numerical simulation methods are a fast and economical way of analyzing the behavior of a product in various mechanical, thermal, electromagnetic and so on. The paper presents comparative results of numerical simulation using the software package SolidWorks impact behavior through the “Drop Test” of half shells made of High Density Polyethylene (HDPE) and of the Arboform LV3 Nature. Simulation watched the half-carcass behavior in three cases of accidental impact, “head”, “corner” and the “back side”. We analyzed the size and location of the maximum voltage and maximum deformation resulting from impact. Simulations have shown for all three cases a maximum voltage increase when using Arboform to use PEDH 93% for impact “forward” and “corner” and only 48.77% “back side” impact. If the maximum displacement, it increasing from carcasses of Arboform 4% for impact “head” and 6% for impact “corner”, but fell by 2.7% for the “back side” impact. The significant increase of stress can be attributed to the higher density of Arboform to PEDH, which led to different weights of the two half-carcasses.

  9. Comparative study on Kasisa Bhasma prepared by two different methods.

    PubMed

    Rajput, Dhirajsingh; Tekale, G S; Patgiri, Bj

    2011-10-01

    Preparation of bhasma (calcined powder of metal/minerals) includes various processing steps like purification (Shodhana), levigation (Bhavana),calcinations cycle(Marana), improving quality and removing blemishes (Amritikarana) etc, processing of bhasma aims at formation of herbo-mineral complex molecule which can act in minimal dosage, palatable, easy for assimilation, highly efficacious with minimal or no complication. Although the most important equipment mentioned for Marana i.e. cow dung cakes and some type of woods are not only difficult to collect but also expensive and create pollution during puta and it's difficult task to give controlled heat in traditional method. Hence, a Modified Portable Bhasma Nirman Yantra (MPBNY) was prepared for puta (equipment for calcination) procedure which is easy to handle, portable and facilitate to supply controlled heat. A comparative study was conducted on Kasisa Bhasma prepared by traditional method and by using MPBNY with special reference to physico-chemical properties. The prepared Kasisa Bhasma was subjected to modern analytical parameters such as A.A.S. (Atomic Absorption Spectroscopy), X.R.D. (X-ray Diffraction) and Ayurvedic parameters eg. Rekhapurnatva (bhasma should enters in between lines of finger), Varitaratva (bhasma should float on the surface of water), Niramlatva (bitter less), Apunarbhava (bhasma should not regain its metallic nature after strong heating with jiggery, Abrus precatorius linn., honey and ghee) and Niruttha (bhasma should not regain its metallic nature after strong heating with silver). It was observed that Kasisa Bhasma of both methods possesses similar organoleptic as well as physico-chemical properties. PMID:23284208

  10. The Neurobehavioural Evaluation in Schizophrenics: A Comparative Study

    PubMed Central

    Ilamkar, Kamini Ramdas

    2013-01-01

    Background: The simple reaction time task assesses the ability of the subject to respond to an external cue and to retrieve a reward. The reaction time provides an indirect index of the processing capability of the central nervous system and a simple means to the determined sensory and the motor performances, which is a neurobehavioural evaluation. A general slowness in the latency in the reaction time tasks and a disengagement deficit in the visual and the hearing oriented tasks were seen in schizophrenics. Aims: In order to clarify the feature of the attention disorders in schizophrenia, a simple reaction time task was given to schizophrenics. Methods and Materials: Schizophrenics (34 males and 20 females, n=54) and healthy controls (40 males and 21 females, n=61) with a mean age of 35±7, who were individually matched for gender and age, were included in the study, by using a response analyser to evaluate the reaction time. Statistical analysis: The performances were expressed in mean ± standard deviation of the reaction time by using the unpaired ‘t’ test. Results and Conclusions: The schizophrenic patients performed poorer than the healthy controls, which indicated a difficulty in sustaining attention and this was statistically very highly significant (p<0.000). The results suggested that the schizophrenics showed inattentiveness in the clinical settings and an emotional disturbance in interpersonal situations. The increased reaction time as compared to that in healthy controls, might be due to the impairment of the psychomotor poverty, disorganization and reality distortion which were associated with the deficits in the cortical neurological functions, such as planning, coordination and sequencing of the motor acts, which showed a greater involvement of the frontal lobe and temporal lobe dysfunction. PMID:23449931

  11. Comparative study on sound production in different Holocentridae species

    PubMed Central

    2011-01-01

    Background Holocentrids (squirrelfish and soldierfish) are vocal reef fishes whose calls and sound-producing mechanisms have been studied in some species only. The present study aims to compare sound-producing mechanisms in different Holocentridae genera (Holocentrus, Myripristis, Neoniphon, Sargocentron) from separate regions and, in some cases, at different developmental stages. An accurate comparison was made by recording six species while being hand-held, by observing TEM) the sonic muscles and by dissections of the sound-producing mechanism. Results In all these species, calls presented harmonics, their dominant frequency was between 80 and 130 Hz and they were composed of trains of 4 to 11 pulses with gradual increasing periods towards the end of the call. In each case, the calls did not provide reliable information on fish size. The sounds were produced by homologous fast-contracting sonic muscles that insert on articulated ribs whose proximal heads are integrated into the swimbladder: each pulse is the result of the back and forth movements of the ribs. Small differences in the shape of the oscillograms of the different species could be related to the number of ribs that are involved in the sound-producing mechanism. These fish species are able to make sounds as soon as they settle on the reef, when they are 40 days old. Comparison between Neoniphon from Madagascar and from Rangiroa in French Polynesia showed a new, unexpected kind of dialect involving differences at the level of pulse distribution. Neoniphon calls were characterised by a single pulse that was isolated at the beginning of the remaining train in Madagascar whereas they did not show any isolated single pulses at the beginning of the call in Rangiroa. Conclusion This family cannot use the acoustic fundamental frequencies (or pulse periods) of grunts to infer the size of partners. Pulse duration and number of pulses are statistically related to fish size. However, these characteristics are

  12. Beyond the Call of Duty: A Qualitative Study of Teachers' Additional Responsibilities Related to Sexuality Education

    ERIC Educational Resources Information Center

    Eisenberg, Marla E.; Madsen, Nikki; Oliphant, Jennifer A.; Resnick, Michael

    2011-01-01

    Seven focus groups were conducted with sexuality educators in Minnesota to explore ways that teaching sexuality education differs from teaching other health education content and to determine if additional supports or resources are needed for sexuality educators. Teachers described many specific additional responsibilities or concerns related to…

  13. Experimental study of combustion characteristics of nanoscale metal and metal oxide additives in biofuel (ethanol)

    PubMed Central

    2011-01-01

    An experimental investigation of the combustion behavior of nano-aluminum (n-Al) and nano-aluminum oxide (n-Al2O3) particles stably suspended in biofuel (ethanol) as a secondary energy carrier was conducted. The heat of combustion (HoC) was studied using a modified static bomb calorimeter system. Combustion element composition and surface morphology were evaluated using a SEM/EDS system. N-Al and n-Al2O3 particles of 50- and 36-nm diameters, respectively, were utilized in this investigation. Combustion experiments were performed with volume fractions of 1, 3, 5, 7, and 10% for n-Al, and 0.5, 1, 3, and 5% for n-Al2O3. The results indicate that the amount of heat released from ethanol combustion increases almost linearly with n-Al concentration. N-Al volume fractions of 1 and 3% did not show enhancement in the average volumetric HoC, but higher volume fractions of 5, 7, and 10% increased the volumetric HoC by 5.82, 8.65, and 15.31%, respectively. N-Al2O3 and heavily passivated n-Al additives did not participate in combustion reactively, and there was no contribution from Al2O3 to the HoC in the tests. A combustion model that utilized Chemical Equilibrium with Applications was conducted as well and was shown to be in good agreement with the experimental results. PMID:21711760

  14. A theoretical study of wave dispersion and thermal conduction for HMX/additive interfaces

    NASA Astrophysics Data System (ADS)

    Long, Yao; Chen, Jun

    2014-04-01

    The wave dispersion rule for non-uniform material is useful for ultrasonic inspection and engine life prediction, and also is key in achieving an understanding of the energy dissipation and thermal conduction properties of solid material. On the basis of linear response theory and molecular dynamics, we derive a set of formulas for calculating the wave dispersion rate of interface systems, and study four kinds of interfaces inside plastic bonded explosives: HMX/{HMX, TATB, F2312, F2313}. (HMX: octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine; TATB: 1,3,5-triamino-2,4,6-trinitrobenzene; F2312, F2313: fluoropolymers). The wave dispersion rate is obtained over a wide frequency range from kHz to PHz. We find that at low frequency, the rate is proportional to the square of the frequency, and at high frequency, the rate couples with the molecular vibration modes at the interface. By using the results, the thermal conductivities of HMX/additive interfaces are derived, and a physical model is built for describing the total thermal conductivity of mixture explosives, including HMX multi-particle systems and {TATB, F2312, F2313}-coated HMX.

  15. Addition reaction of alkyl radical to C60 fullerene: Density functional theory study

    NASA Astrophysics Data System (ADS)

    Tachikawa, Hiroto; Kawabata, Hiroshi

    2016-02-01

    Functionalized fullerenes are known as a high-performance molecules. In this study, the alkyl-functionalized fullerenes (denoted by R-C60) have been investigated by means of the density functional theory (DFT) method to elucidate the effects of functionalization on the electronic states of fullerene. Also, the reaction mechanism of alkyl radicals with C60 was investigated. The methyl, ethyl, propyl, and butyl radicals (denoted by n = 1-4, where n means the number of carbon atoms in the alkyl radical) were examined as alkyl radicals. The DFT calculation showed that the alkyl radical binds to the carbon atom of C60 at the on-top site, and a strong C-C single bond is formed. The binding energies of alkyl radicals to C60 were distributed in the range of 31.8-35.1 kcal mol-1 at the CAM-B3LYP/6-311G(d,p) level. It was found that the activation barrier exists before alkyl addition, the barrier heights were calculated to be 2.1-2.8 kcal mol-1. The electronic states of R-C60 complexes were discussed on the basis of the theoretical results.

  16. Ecological Optimization and Parametric Study of an Irreversible Regenerative Modified Brayton Cycle with Isothermal Heat Addition

    NASA Astrophysics Data System (ADS)

    Tyagi, Sudhir K.; Kaushik, Subhash C.; Tiwari, Vivek

    2003-12-01

    An ecological optimization along with a detailed parametric study of an irreversible regenerative Brayton heat engine with isothermal heat addition have been carried out with external as well as internal irreversibilities. The ecological function is defined as the power output minus the power loss (irreversibility) which is ambient temperature times the entropy generation rate. The external irreversibility is due to finite temperature difference between the heat engine and the external reservoirs while the internal irreversibilities are due to nonisentropic compression and expansion processes in the compressor and the turbine respectively and the regenerative heat loss. The ecological function is found to be an increasing function of the isothermal-, sink- and regenerative-side effectiveness, isothermal-side inlet temperature, component efficiencies and sink-side temperature while it is found to be a decreasing function of the isobaric-side temperature and effectiveness and the working fluid heat capacitance rate. The effects of the isobaric-side effectiveness are found to be more than those of the other parameters and the effects of turbine efficiency are found to be more than those of the compressor efficiency on all the performance parameters of the cycle.

  17. Theoretical study of addition reactions of carbene, silylene, and germylene to carbon nanotubes

    NASA Astrophysics Data System (ADS)

    Chu, Ying-Ying; Su, Ming-Der

    2004-08-01

    A theoretical study of the mechanism of the reaction of a single-walled carbon nanotube (SWCNT) with carbene (H 2C), silylene (H 2Si), and germylene (H 2Ge) has been carried out using a two-layered ONIOM(B3LYP/6-311G ∗:PM3) approach. The main findings are as follows: (1) The computational results based on the method used in this work are in good agreement with recent theoretical findings [Angew. Chem. Int. Ed. 41 (2002) 1853]. That is, SWCNTs with H 2C, H 2Si, and H 2Ge addends favor opened structures rather than three-membered rings. (2) The greater the atomic number of the carbene center, the larger the activation energy and the less exothermic (or the more endothermic) the cycloaddition reaction becomes. Therefore, addition to the C dbnd C bond of a SWCNT is more difficult the heavier the carbene center. (3) The theoretical observations suggest that the singlet-triplet splitting of a carbene can be used as a guide to its reactivity during the SWCNT cycloaddition process.

  18. Study on Antiwear and Repairing Performances about Mass of Nano-copper Lubricating Additives to 45 Steel

    NASA Astrophysics Data System (ADS)

    Wang, X. L.; Yin, Y. L.; Zhang, G. N.; Wang, W. Y.; Zhao, K. K.

    Nano-copper usually serve for lubricating additives in tribology field. The antiwear and reducing friction performances both basic lubrication oil and basic lubrication oil with nano-copper in different mass were tested by friction wear test machine. The morphologies and the main elements of worn surfaces were analyzed by SEM. The results indicated that nano-copper could improve tribology performances of basic lubrication oil. Comparing with base lubrication oil, the mass is 0.15% of nano-copper, the friction coefficient and the worn trace width can be reduced 34% and 32% respectively. Nano-copper can form self-repairing film in lubrication oil which availably separates the friction materials in friction process. Therefore, nano-copper has wonderful antiwear, reducing friction and self-repairing performances. And the function mechanism of Cu nanoparticles is studied in the paper.

  19. Additional weight load increases freezing of gait episodes in Parkinson's disease; an experimental study.

    PubMed

    Mensink, Senja H G; Nonnekes, Jorik; van Bon, Geert; Snijders, Anke H; Duysens, Jacques; Weerdesteyn, Vivian; Bloem, Bastiaan R; Oude Nijhuis, Lars B

    2014-05-01

    Freezing of gait is an episodic gait disorder,characterized by the inability to generate effective forward stepping movements. The pathophysiology underlying freezing of gait remains insufficiently understood, and this hampers the development of better treatment strategies.Preliminary evidence suggests that impaired force control during walking may contribute to freezing episodes, with difficulty to unload the swing leg and initiate the swing phase. Here, we used external loading to manipulate force control and to investigate its influence on freezing of gait.Twelve Parkinson's disease patients with freezing of gait performed three contrasting tasks: (1) loaded gait while wearing a belt fortified with lead weights; (2) weight supported gait using a parachute harness connected to a rigid metal cable running above the gait trajectory; and (3)normal gait. Gait tasks were used to provoke freezing episodes, including rapid 360° turns. Freezing episodes were quantified using blinded, videotaped clinical assessment. Furthermore, ground reaction forces and body kinematics were recorded. Loading significantly increased the mean number of freezing episodes per trial compared to the normal gait condition (P<0.05), but the effect of weight support was not consistent. Loading particularly increased the number of freezing episodes during rapid short steps. Step length was significantly smaller during loaded gait compared to normal gait (P<0.05), but changes in anticipatory postural adjustments were not different.Our results may point to impaired force control playing a key role in freezing of gait. Future studies should further investigate the mechanism, i.e., the contribution of deficient load feedback, and evaluate which forms of weight support might offer treatment opportunities. PMID:24658705

  20. Food additives.

    PubMed

    Berglund, F

    1978-01-01

    The use of additives to food fulfils many purposes, as shown by the index issued by the Codex Committee on Food Additives: Acids, bases and salts; Preservatives, Antioxidants and antioxidant synergists; Anticaking agents; Colours; Emulfifiers; Thickening agents; Flour-treatment agents; Extraction solvents; Carrier solvents; Flavours (synthetic); Flavour enhancers; Non-nutritive sweeteners; Processing aids; Enzyme preparations. Many additives occur naturally in foods, but this does not exclude toxicity at higher levels. Some food additives are nutrients, or even essential nutritents, e.g. NaCl. Examples are known of food additives causing toxicity in man even when used according to regulations, e.g. cobalt in beer. In other instances, poisoning has been due to carry-over, e.g. by nitrate in cheese whey - when used for artificial feed for infants. Poisonings also occur as the result of the permitted substance being added at too high levels, by accident or carelessness, e.g. nitrite in fish. Finally, there are examples of hypersensitivity to food additives, e.g. to tartrazine and other food colours. The toxicological evaluation, based on animal feeding studies, may be complicated by impurities, e.g. orthotoluene-sulfonamide in saccharin; by transformation or disappearance of the additive in food processing in storage, e.g. bisulfite in raisins; by reaction products with food constituents, e.g. formation of ethylurethane from diethyl pyrocarbonate; by metabolic transformation products, e.g. formation in the gut of cyclohexylamine from cyclamate. Metabolic end products may differ in experimental animals and in man: guanylic acid and inosinic acid are metabolized to allantoin in the rat but to uric acid in man. The magnitude of the safety margin in man of the Acceptable Daily Intake (ADI) is not identical to the "safety factor" used when calculating the ADI. The symptoms of Chinese Restaurant Syndrome, although not hazardous, furthermore illustrate that the whole ADI

  1. Comparative study of different waste biomass for energy application.

    PubMed

    Motghare, Kalyani A; Rathod, Ajit P; Wasewar, Kailas L; Labhsetwar, Nitin K

    2016-01-01

    Biomass is available in many varieties, consisting of crops as well as its residues from agriculture, forestry, and the agro-industry. These different biomass find their way as freely available fuel in rural areas but are also responsible for air pollution. Emissions from such solid fuel combustion to indoor, regional and global air pollution largely depend on fuel types, combustion device, fuel properties, fuel moisture, amount of air supply for combustion and also on climatic conditions. In both economic and environment point of view, gasification constitutes an attractive alternative for the use of biomass as a fuel, than the combustion process. A large number of studies have been reported on a variety of biomass and agriculture residues for their possible use as renewable fuels. Considering the area specific agriculture residues and biomass availability and related transportation cost, it is important to explore various local biomass for their suitability as a fuel. Maharashtra (India) is the mainstay for the agriculture and therefore, produces a significant amount of waste biomass. The aim of the present research work is to analyze different local biomass wastes for their proximate analysis and calorific value to assess their potential as fuel. The biomass explored include cotton waste, leaf, soybean waste, wheat straw, rice straw, coconut coir, forest residues, etc. mainly due to their abundance. The calorific value and the proximate analysis of the different components of the biomass helped in assessing its potential for utilization in different industries. It is observed that ash content of these biomass species is quite low, while the volatile matter content is high as compared to Indian Coal. This may be appropriate for briquetting and thus can be used as a domestic fuel in biomass based gasifier cook stoves. Utilizing these biomass species as fuel in improved cook-stove and domestic gasifier cook-stoves would be a perspective step in the rural energy and

  2. PROSPECTIVE RANDOMIZED STUDY COMPARING TWO ANESTHETIC METHODS FOR SHOULDER SURGERY

    PubMed Central

    Ikemoto, Roberto Yukio; Murachovsky, Joel; Prata Nascimento, Luis Gustavo; Bueno, Rogerio Serpone; Oliveira Almeida, Luiz Henrique; Strose, Eric; de Mello, Sérgio Cabral; Saletti, Deise

    2015-01-01

    Objective: To evaluate the efficacy of suprascapular nerve block in combination with infusion of anesthetic into the subacromial space, compared with interscalene block. Methods: Forty-five patients with small or medium-sized isolated supraspinatus tendon lesions who underwent arthroscopic repair were prospectively and comparatively evaluated through random assignation to three groups of 15, each with a different combination of anesthetic methods. The efficacy of postoperative analgesia was measured using the visual analogue scale for pain and the analgesic, anti-inflammatory and opioid drug consumption. Inhalation anesthetic consumption during surgery was also compared between the groups. Results: The statistical analysis did not find any statistically significant differences among the groups regarding anesthetic consumption during surgery or postoperative analgesic efficacy during the first 48 hours. Conclusion: Suprascapular nerve block with infusion of anesthetic into the subacromial space is an excellent alternative to interscalene block, particularly in hospitals in which an electrical nerve stimulating device is unavailable. PMID:27022569

  3. Comparative Study of Message Passing and Shared Memory Parallel Programming Models in Neural Network Training

    SciTech Connect

    Vitela, J.; Gordillo, J.; Cortina, L; Hanebutte, U.

    1999-12-14

    It is presented a comparative performance study of a coarse grained parallel neural network training code, implemented in both OpenMP and MPI, standards for shared memory and message passing parallel programming environments, respectively. In addition, these versions of the parallel training code are compared to an implementation utilizing SHMEM the native SGI/CRAY environment for shared memory programming. The multiprocessor platform used is a SGI/Cray Origin 2000 with up to 32 processors. It is shown that in this study, the native CRAY environment outperforms MPI for the entire range of processors used, while OpenMP shows better performance than the other two environments when using more than 19 processors. In this study, the efficiency is always greater than 60% regardless of the parallel programming environment used as well as of the number of processors.

  4. Psychiatric Diagnostic Interviews for Children and Adolescents: A Comparative Study

    ERIC Educational Resources Information Center

    Angold, Adrian; Erkanli, Alaattin; Copeland, William; Goodman, Robert; Fisher, Prudence W.; Costello, E. Jane

    2012-01-01

    Objective: To compare examples of three styles of psychiatric interviews for youth: the Diagnostic Interview Schedule for Children (DISC) ("respondent-based"), the Child and Adolescent Psychiatric Assessment (CAPA) ("interviewer-based"), and the Development and Well-Being Assessment (DAWBA) ("expert judgment"). Method: Roughly equal numbers of…

  5. Comparative Study of Student Support Services of UKOU and SLOU

    ERIC Educational Resources Information Center

    Gujjar, Aijaz Ahmed; Choudhry, Bushra Naoreen; Choudhry, Amtul Hafeez

    2008-01-01

    This paper attempts to compare the availability, quality, similarities and differences of students' support services in United Kingdom Open University (UKOU) and Sri Lanka Open University (SLOU) and also to identify and enlist the deficiencies that SLOU students are facing in the student support services. To get the desired end four hundred…

  6. Automated Essay Scoring versus Human Scoring: A Comparative Study

    ERIC Educational Resources Information Center

    Wang, Jinhao; Brown, Michelle Stallone

    2007-01-01

    The current research was conducted to investigate the validity of automated essay scoring (AES) by comparing group mean scores assigned by an AES tool, IntelliMetric [TM] and human raters. Data collection included administering the Texas version of the WriterPlacer "Plus" test and obtaining scores assigned by IntelliMetric [TM] and by human…

  7. Reforming Teaching Globally. Oxford Studies in Comparative Education

    ERIC Educational Resources Information Center

    Tatto, Maria Teresa, Ed.

    2007-01-01

    This book seeks to raise the discussion of globalisation's effects on teacher education, development and work, and its reforms and institutions, to a more theoretical and analytical level, and to provide specific examples in the comparative tradition to illustrate teacher policy in the context of education systems' widespread variability and…

  8. Inmate Movements and Prison Uprisings: A Comparative Study.

    ERIC Educational Resources Information Center

    Pederson, William D.

    1978-01-01

    Fifteen "criminal" and political uprisings from inmate movements in American, Soviet, and German prisons are compared. Conditions of deprivation related to prison violence are linked with attitudinal, structural, and temporal factors. Findings are that inmate movements are a rare phenomenon in comparison with isolated prison uprisings. (KC)

  9. Social Cartography: A New Methodology for Comparative Studies.

    ERIC Educational Resources Information Center

    Liebman, Martin; Paulston, Rolland

    Comparative educators can enhance research by developing and including in their research findings a cognitive map to show perceptions of how knowledge claims interrelate. Three research relationships utilize different methodologies: (1) the researcher objectifies the phenomena; (2) the researcher position is preferential to the research object but…

  10. Study of the Comparability of the WISC and the WAIS

    ERIC Educational Resources Information Center

    Simpson, Robert L.

    1970-01-01

    Subtests of the two instruments were administered in randomized order to 120 16 year old students. Analysis of variance revealed higher WAIS than WISC Verbal (p is less than .001), Performance (p is less than .01), and Full Scales (p is less than .001) IQs. The WISC and WAIS are not comparable for below average intelligence students. Reprints from…

  11. Parental Bereavement after Suicide and Accident: A Comparative Study.

    ERIC Educational Resources Information Center

    Seguin, Monique; And Others

    1995-01-01

    Compares differences in the bereavement process for 30 survivors of suicide versus 30 survivors of car accidents. Indicates suicide survivors were more depressed than accident survivors at the first measure but not at the second measure. Survivors of suicide experienced greater feelings of shame and had experienced more life events after the death…

  12. A Corpus-Based Comparative Study of "Learn" and "Acquire"

    ERIC Educational Resources Information Center

    Yang, Bei

    2016-01-01

    As an important yet intricate linguistic feature in English language, synonymy poses a great challenge for second language learners. Using the 100 million-word British National Corpus (BNC) as data and the software Sketch Engine (SkE) as an analyzing tool, this article compares the usage of "learn" and "acquire" used in natural…

  13. A Comparative Study of Standard-Setting Methods.

    ERIC Educational Resources Information Center

    Livingston, Samuel A.; Zieky, Michael J.

    1989-01-01

    The borderline group standard-setting method (BGSM), Nedelsky method (NM), and Angoff method (AM) were compared, using reading scores for 1,948 and mathematics scores for 2,191 sixth through ninth graders. The NM and AM were inconsistent with the BGSM. Passing scores were higher where students were more able. (SLD)

  14. Teaching Organic Synthesis: A Comparative Case Study Approach

    ERIC Educational Resources Information Center

    Vosburg, David A.

    2008-01-01

    In this course, students encounter reactions and mechanisms in the context of landmark syntheses of biologically important molecules. Students closely examine pairs of syntheses of related or identical molecules to facilitate their appreciation for synthetic strategy. They then write short, creative papers that critically compare the two synthetic…

  15. Understanding Organizational Change: A Comparative Study of Multifaceted Interventions.

    ERIC Educational Resources Information Center

    Pasmore, William A.; King, Donald C.

    1978-01-01

    Investigates the differential impacts of sociotechnical systems, job redesign, and survey-feedback interventions on a wide array of attitudinal and performance measures in comparable units of an organization. Attitudinal effects were quite similar; however, only the sociotechnical system intervention resulted in major productivity improvements and…

  16. The Comparative Study of First and Second Language Development.

    ERIC Educational Resources Information Center

    Clahsen, Harald

    1990-01-01

    Compares different approaches to first- and second-language development. It is argued that the observed differences between first- and (adult) second-language acquisition can be accounted for by assuming that adult second-language learners can not use Universal Grammar principles as a learning device in the same way that first-language learners…

  17. Comparative Actions of Barbiturates Studied by Pollen Grain Germination.

    ERIC Educational Resources Information Center

    Kordan, Herbert A.; Mumford, Pauline M.

    1979-01-01

    Describes a simple experimental system whereby the comparative actions of long, medium, and short-acting barbiturates can be demonstrated in a relatively short period of time under optical microscopy using pollen grains as the biological test or assay system. (Author/HM)

  18. Vocation, Motivation and Approaches to Learning: A Comparative Study

    ERIC Educational Resources Information Center

    Arquero, Jose Luis; Fernández-Polvillo, Carmen; Hassall, Trevor; Joyce, John

    2015-01-01

    Purpose: The individual characteristics of students can have a strong influence on the success of the adopted innovations in terms of their transferability and sustainability. The purpose of this paper is to compare the motivations and approaches to learning on degrees with differing vocational components. Design/methodology/approach:…

  19. A digital process for additive manufacturing of occlusal splints: a clinical pilot study.

    PubMed

    Salmi, Mika; Paloheimo, Kaija-Stiina; Tuomi, Jukka; Ingman, Tuula; Mäkitie, Antti

    2013-07-01

    The aim of this study was to develop and evaluate a digital process for manufacturing of occlusal splints. An alginate impression was taken from the upper and lower jaws of a patient with temporomandibular disorder owing to cross bite and wear of the teeth, and then digitized using a table laser scanner. The scanned model was repaired using the 3Data Expert software, and a splint was designed with the Viscam RP software. A splint was manufactured from a biocompatible liquid photopolymer by stereolithography. The system employed in the process was SLA 350. The splint was worn nightly for six months. The patient adapted to the splint well and found it comfortable to use. The splint relieved tension in the patient's bite muscles. No sign of tooth wear or significant splint wear was detected after six months of testing. Modern digital technology enables us to manufacture clinically functional occlusal splints, which might reduce costs, dental technician working time and chair-side time. Maximum-dimensional errors of approximately 1 mm were found at thin walls and sharp corners of the splint when compared with the digital model. PMID:23614943

  20. A digital process for additive manufacturing of occlusal splints: a clinical pilot study

    PubMed Central

    Salmi, Mika; Paloheimo, Kaija-Stiina; Tuomi, Jukka; Ingman, Tuula; Mäkitie, Antti

    2013-01-01

    The aim of this study was to develop and evaluate a digital process for manufacturing of occlusal splints. An alginate impression was taken from the upper and lower jaws of a patient with temporomandibular disorder owing to cross bite and wear of the teeth, and then digitized using a table laser scanner. The scanned model was repaired using the 3Data Expert software, and a splint was designed with the Viscam RP software. A splint was manufactured from a biocompatible liquid photopolymer by stereolithography. The system employed in the process was SLA 350. The splint was worn nightly for six months. The patient adapted to the splint well and found it comfortable to use. The splint relieved tension in the patient's bite muscles. No sign of tooth wear or significant splint wear was detected after six months of testing. Modern digital technology enables us to manufacture clinically functional occlusal splints, which might reduce costs, dental technician working time and chair-side time. Maximum-dimensional errors of approximately 1 mm were found at thin walls and sharp corners of the splint when compared with the digital model. PMID:23614943

  1. Mass analysis addition to the Differential Ion Flux Probe (DIFP) study

    NASA Technical Reports Server (NTRS)

    Wright, K. H., Jr.; Jolley, Richard

    1994-01-01

    The objective of this study is to develop a technique to measure the characteristics of space plasmas under highly disturbed conditions; e.g., non-Maxwellian plasmas with strong drifting populations and plasmas contaminated by spacecraft outgassing. The approach, conducted in conjunction with current MSFC activities, is to extend the capabilities of the Differential Ion Flux Probe (DIFP) to include a high throughput mass measurement that does not require either high voltage or contamination sensitive devices such as channeltron electron multipliers or microchannel plates. This will significantly reduce the complexity and expense of instrument fabrication, testing, and integration of flight hardware compared to classical mass analyzers. The feasibility of the enhanced DIFP has been verified by using breadboard test models in a controlled plasma environment. The ability to manipulate particles through the instrument regardless of incident angle, energy, or ionic component has been amply demonstrated. The energy analysis mode is differential and leads directly to a time-of-flight mass measurement. With the new design, the DIFP will separate multiple ion streams and analyze each stream independently for ion flux intensity, velocity (including direction of motion), mass, and temperature (or energy distribution). In particular, such an instrument will be invaluable on follow-on electrodynamic TSS missions and, possibly, for environmental monitoring on the space station.

  2. ALUM ADDITION AND STEP-FEED STUDIES IN OXYGEN-ACTIVATED SLUDGE

    EPA Science Inventory

    A plug flow, O2-activated sludge process was operated with alum addition to remove phosphorus and with lime addition to prevent the process pH from decreasing below 6.4. The O2 reactor was operated at F/M ratios between 0.18 to 0.24 gm of BOD5/gm of MLVSS/day in a typical co-curr...

  3. Chemostat Studies of TCE-Dehalogenating Anaerobic Consortia under Excess and Limited Electron Donor Addition

    NASA Astrophysics Data System (ADS)

    Semprini, L.; Azizian, M.; Green, J.; Mayer-Blackwell, K.; Spormann, A. M.

    2015-12-01

    Two cultures - the Victoria Strain (VS) and the Evanite Strain (EV), enriched with the organohalide respiring bacteria Dehalococcoides mccartyi - were grown in chemostats for more than 4 years at a mean cell residence time of 50 days. The slow doubling rate represents growth likely experienced in the subsurface. The chemostats were fed formate as an electron donor and trichloroethene (TCE) as the terminal electron acceptor. Under excess formate conditions, stable operation was observed with respect to TCE transformation, steady-state hydrogen (H2) concentrations (40 nM), and the structure of the dehalogenating community. Both cultures completely transformed TCE to ethene, with minor amounts of vinyl chloride (VC) observed, along with acetate formation. When formate was limited, TCE was transformed incompletely to ethene (40-60%) and VC (60- 40%), and H2 concentrations ranged from 1 to 3 nM. The acetate concentration dropped below detection. Batch kinetic studies of TCE transformation with chemostat harvested cells found transformation rates of c-DCE and VC were greatly reduced when the cells were grown with limited formate. Upon increasing formate addition to the chemostats, from limited to excess, essentially complete transformation of TCE to ethene was achieved. The increase in formate was associated with an increase in H2 concentration and the production of acetate. Results of batch kinetic tests showed increases in transformation rates for TCE and c-DCE by factors of 3.5 and 2.5, respectively, while VC rates increased by factors of 33 to 500, over a six month period. Molecular analysis of chemostat samples is being performed to quantify the changes in copy numbers of reductase genes and to determine whether shifts in the strains of Dehalococcoides mccartyi where responsible for the observed rate increases. The results demonstrate the importance of electron donor supply for successful in-situ remediation.

  4. Biological effect of food additive titanium dioxide nanoparticles on intestine: an in vitro study.

    PubMed

    Song, Zheng-Mei; Chen, Ni; Liu, Jia-Hui; Tang, Huan; Deng, Xiaoyong; Xi, Wen-Song; Han, Kai; Cao, Aoneng; Liu, Yuanfang; Wang, Haifang

    2015-10-01

    Titanium dioxide nanoparticles (TiO2 NPs) are widely found in food-related consumer products. Understanding the effect of TiO2 NPs on the intestinal barrier and absorption is essential and vital for the safety assessment of orally administrated TiO2 NPs. In this study, the cytotoxicity and translocation of two native TiO2 NPs, and these two TiO2 NPs pretreated with the digestion simulation fluid or bovine serum albumin were investigated in undifferentiated Caco-2 cells, differentiated Caco-2 cells and Caco-2 monolayer. TiO2 NPs with a concentration less than 200 µg ml(-1) did not induce any toxicity in differentiated cells and Caco-2 monolayer after 24 h exposure. However, TiO2 NPs pretreated with digestion simulation fluids at 200 µg ml(-1) inhibited the growth of undifferentiated Caco-2 cells. Undifferentiated Caco-2 cells swallowed native TiO2 NPs easily, but not pretreated NPs, implying the protein coating on NPs impeded the cellular uptake. Compared with undifferentiated cells, differentiated ones possessed much lower uptake ability of these TiO2 NPs. Similarly, the traverse of TiO2 NPs through the Caco-2 monolayer was also negligible. Therefore, we infer the possibility of TiO2 NPs traversing through the intestine of animal or human after oral intake is quite low. This study provides valuable information for the risk assessment of TiO2 NPs in food. PMID:26106068

  5. A study of the electrochemistry of nickel hydroxide electrodes with various additives

    NASA Astrophysics Data System (ADS)

    Zhu, Wen-Hua; Ke, Jia-Jun; Yu, Hong-Mei; Zhang, Deng-Jun

    Nickel composite electrodes (NCE) with various additives are prepared by a chemical impregnation method from nitrate solutions on sintered porous plaques. The electrochemical properties, such as utilization of active material, swelling and the discharge potential of the nickel oxide electrode (NOE) are determined mainly through the composition of the active material and the characteristics of nickel plaques. Most additives (Mg, Ca, Sr, Ba, Zn, Cd, Co, Li and Al hydroxide) exert effects on the discharge potential and swelling of the NOE. Chemical co-precipitation with the addition of calcium, zinc, magnesium and barium hydroxide increases the discharge potential by more than 20 mV, but that with zinc hydroxide results in an obvious decrease of active-material utilization and that with calcium and magnesium hydroxide produces a larger increase of electrode thickness. The effects of anion additives are also examined. Less than 1% mol of NiS in the active material increases the discharge potential. Cadmium, cobalt and zinc hydroxide are excellent additives for preventing swelling of the NCE. Slow voltammetry (0.2 mV s -1) in 6 M KOH is applied to characterize the oxygen-evolving potential of the NCE. The difference between the oxygen-evolution potential and the potential of the oxidation peak for the NCE with additives of calcium, lithium, barium and aluminium hydroxide is at least + 60 mV.

  6. 78 FR 68461 - Guidance for Industry: Studies To Evaluate the Utility of Anti-Salmonella Chemical Food Additives...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-14

    ... Guidance for Industry: Studies to Evaluate the Utility of Anti-Salmonella Chemical Food Additives in Feeds... HUMAN SERVICES Food and Drug Administration Guidance for Industry: Studies To Evaluate the Utility of Anti- Salmonella Chemical Food Additives in Feeds; Request for Comments AGENCY: Food and...

  7. Ultraviolet radiation penetrating vehicle glass: a field based comparative study

    NASA Astrophysics Data System (ADS)

    Kimlin, M. G.; Parisi, A. V.

    1999-04-01

    The solar UV transmitted through automobile glass was measured in the field in two cars using a spectroradiometer. The two cars were identical except that one of the cars had all of the windows (except the windshield) tinted. The measured spectral erythemal UV on a horizontal plane with the windows fully closed was reduced in the tinted car by a factor of 42 when compared with the erythemal UV measured in the untinted car. The ambient UVA irradiances at various locations within four different makes of car and a tractor were also measured with a broad band UVA hand-held meter. The average normalized daily UVA exposure (measured with a broad band UVA meter) was 1.3 times higher in a large family sedan when compared with that in a small hatchback and the UVA exposure in a car with tinted windows was 3.8 times less than in a similar untinted car.

  8. Comparative study of infrared techniques for fast biogeochemical sediment analyses

    NASA Astrophysics Data System (ADS)

    Hahn, A.; RoséN, P.; Kliem, P.; Ohlendorf, C.; Zolitschka, B.

    2011-10-01

    Analysis of sediment samples in the visible to mid infrared (IR) region requires small amounts of sample material and enables rapid and cost efficient geochemical analysis of mineral and organic sediment components. Here we use geochemical properties (total organic and inorganic carbon, biogenic silica, total nitrogen) from the ICDP deep drilling project PASADO to compare three different IR spectroscopy techniques: Diffuse Reflectance Fourier Transform IR Spectrometry (DRIFTS), Attenuated Total Reflectance Fourier Transform IR Spectroscopy (ATR-FTIRS) and Visible Near IR Spectroscopy (VNIRS). ATR-FTIRS and VNIRS are more rapid techniques compared to DRIFTS. Results show that calibration models developed using DRIFTS are most robust (correlation coefficient: R = 0.92 for TIC, R = 0.84 for BSi, R = 0.97 for TOC, R = 0.95 for TN). However, good statistical performance was also obtained by using ATR-FTIRS and VNIRS. When time and costs are limiting factors, these tools may be given preference for rapid biogeochemical screening.

  9. Comparative studies on uptake pathway of cadmium by Perna viridis

    NASA Astrophysics Data System (ADS)

    Fang, Zhanqiang

    2006-01-01

    Experiments were designed to expose the filter-feeding bivalve Perna viridis to different Cd-contaminated water environments in order to compare the different pathways through which Cd is accumulated. Results show that mussels can accumulate Cd through seawater, food, sediment and suspended particle pathways in a short period of time. Mussels' uptake of Cd through the seawater pathway reaches the highest concentration approximately 3 and 9 times larger than through the algae and sediment pathways respectively after 7 d. This indicates that the Cd-accumulation through seawater is most efficient. Results also indicate that the uptake directly through contaminated algae, particles or sediments ingested by mussels is less important when compared with the uptake of Cd by mussels through the seawater pathway. Metal uptake pathways and mechanisms of bioaccumulation by marine bivalve are also discussed in this paper.

  10. Clinical characteristics and outcomes of neonatal pertussis: a comparative study.

    PubMed

    Castagnini, Luis A; Munoz, Flor M

    2010-03-01

    We describe the features and outcomes of neonatal pertussis and compare these with neonates with non-pertussis acute respiratory illness from July 2000 through December 2007. Patients with pertussis had a more severe course of disease as evidenced by the clinical presentation, length of hospitalization, and oxygen requirement. Clinicians should have a high index of suspicion so that appropriate supportive care can be initiated promptly. PMID:20056236

  11. Comparative study of above ground biomass estimates for conterminous US

    NASA Astrophysics Data System (ADS)

    Neeti, N.; Kennedy, R. E.

    2013-12-01

    Accurate estimates of forest biomass are important for carbon accounting at both regional and national scale. There are four above ground biomass (AGB) maps available for conterminous US, one from the National Aeronautics and Space Administration (NASA), two from the United States Forest Service (USFS) (Blackard and Wilson) and one from the Woods Hole Research Center (WHRC). Although all four maps are meant to represent similar quantities, spatial patterns of AGB vary considerably from map to map. To use any of these AGB maps for carbon accounting, it is important to understand sources of uncertainty in individual maps and agreement and disagreement among them. Therefore, we compared the four AGB maps at ecoregion and state level to gain understanding of map consistency, leveraging discrepancies among maps to gain insight into the method and data sources. We also developed statewide summaries to compare with FIA forest AGB estimates, which are typically reported at the state level. We examined both absolute differences among these aggregated maps, and relative differences among regions within each map. The result shows that NASA biomass estimates are highest and Blackard estimates are lowest compared to other maps at both ecoregion and state level. The AGB for WHRC and Wilson are very similar at both ecoregion and state level specifically in the lower biomass regions compared to higher biomass regions. This could be associated with the differences in the spatial resolution of the data sources uses to generate these maps. At state level, WHRC map is found to be most similar and NASA biomass estimates least similar to FIA plot data. We discuss these differences in light of the different methods and data sources used to generate the maps.

  12. Comparative studies in direct slow-neutron capture calculations

    SciTech Connect

    Mughabghab, S.F.

    1987-08-01

    Primary E1 transitions due to thermal neutron capture by the nuclides /sup 9/Be, /sup 32,34/S, /sup 40,42,44,46,48/Ca, and /sup 58/Ni are quantitatively interpreted by the Lane-Lynn formula and are compared with recent optical model calculations. The two approaches are equivalent provided the internal region of the nucleus is excluded in the optical model approach. Theoretical justifications for such a procedure are briefly presented. 32 refs., 4 tabs.

  13. A comparative study of electric power distribution systems for spacecraft

    NASA Technical Reports Server (NTRS)

    Stuart, Thomas A.; King, Roger J.

    1990-01-01

    The electric power distribution systems for spacecraft are compared concentrating on two interrelated issues: the choice between dc and high frequency ac, and the converter/inverter topology to be used at the power source. The relative merits of dc and ac distribution are discussed. Specific converter and inverter topologies are identified and analyzed in detail for the purpose of detailed comparison. Finally, specific topologies are recommended for use in dc and ac systems.

  14. Comparative Study of Metadata Standards and Metadata Repositories

    NASA Astrophysics Data System (ADS)

    Pahuja, Gunjan

    2011-12-01

    Lot of work is being accomplished in the national and international standards communities to reach a consensus on standardizing metadata and repositories for organizing the metadata. Descriptions of several metadata standards and their importance to statistical agencies are provided in this paper. Existing repositories based on these standards help to promote interoperability between organizations, systems, and people. Repositories are vehicles for collecting, managing, comparing, reusing, and disseminating the designs, specifications, procedures, and outputs of systems, e.g. statistical surveys.

  15. [Comparative studies on fissure sealing: composite versus Cermet cement].

    PubMed

    Hickel, R; Voss, A

    1989-06-01

    Fifty two molars sealed with either composite or Cermet cement were compared. The composite sealant was applied after enamel etching using a rubber dam. Before sealing with Cermet cement the enamel was only cleaned with pumice powder and sodium hypochlorie and the material was applied without enamel etching. After an average follow-up of 1.6 years composite sealants proved to be significantly more reliable. Cermet cement sealings showed defects more frequently. PMID:2517111

  16. Comparative study on adhesive performance of functional monomers.

    PubMed

    Yoshida, Y; Nagakane, K; Fukuda, R; Nakayama, Y; Okazaki, M; Shintani, H; Inoue, S; Tagawa, Y; Suzuki, K; De Munck, J; Van Meerbeek, B

    2004-06-01

    Mild self-etch adhesives demineralize dentin only partially, leaving hydroxyapatite around collagen within a submicron hybrid layer. We hypothesized that this residual hydroxyapatite may serve as a receptor for chemical interaction with the functional monomer and, subsequently, contribute to adhesive performance in addition to micro-mechanical hybridization. We therefore chemically characterized the adhesive interaction of 3 functional monomers with synthetic hydroxyapatite, using x-ray photoelectron spectroscopy and atomic absorption spectrophotometry. We further characterized their interaction with dentin ultra-morphologically, using transmission electron microscopy. The monomer 10-methacryloxydecyl dihydrogen phosphate (10-MDP) readily adhered to hydroxyapatite. This bond appeared very stable, as confirmed by the low dissolution rate of its calcium salt in water. The bonding potential of 4-methacryloxyethyl trimellitic acid (4-MET) was substantially lower. The monomer 2-methacryloxyethyl phenyl hydrogen phosphate (phenyl-P) and its bond to hydroxyapatite did not appear to be hydrolytically stable. Besides self-etching dentin, specific functional monomers have additional chemical bonding efficacy that is expected to contribute to their adhesive potential to tooth tissue. PMID:15153451

  17. Study of sorption of two sulfonylurea type of herbicides and their additives on soils and soil components.

    PubMed

    Földényi, Rita; Tóth, Zoltán; Samu, Gyöngyi; Érsek, Csaba

    2013-01-01

    The sorption of two sulfonylurea type herbicides (chlorsulfuron: (1-(2-chlorophenylsulfonyl)-3-(4-methoxy-6-methyl-1,3,5-triazin-2-yl)urea; tribenuron methyl: (methyl-2-[N-(4-methoxy-6-methyl-1,3,5-triazin-2-yl)-3-(methyl-ureido)-sulfonyl]-benzoate) was studied on sand and chernozem soil adsorbents. Experimental results for solutions prepared from the pure ingredients were compared to those prepared from the appropriate formulated commercial products. At small concentrations, the extent of adsorption of the active ingredient was higher than from the formulation containing solutions. Environmental fate and effects of the forming agents are less investigated because they rarely have concentration limits recommended by authorities. In addition to the adsorption of active ingredients, therefore, the sorption behavior of a widely used additive Supragil WP (sodium diisopropyl naphthalene sulphonate) was also studied. This dispersant is an anionic forming agent applied in a lot of pesticide formulations. Using three different soils (sand, brown forest, chernozem) as adsorbents two-step isotherms were obtained. The role of the soil organic matter (OM) was significant in the adsorption mechanism because the adsorbed amounts of the dispersant correlated with the specific surface area as well as with the total organic carbon (TOC) content of the soils. The sorption behavior indicates the operation of hydrophobic interaction mechanism between the soil OM and the dispersant. These results are supported by our further sorption experiments on clays, too. Zeta potential measurements seem to be promising for the interpretation of multi-step isotherms. The application of this technique proved that higher concentrations of the anionic forming agent assisted the peptization of soil organic matter (SOM) resulting in stable colloidal solution dominated by negative charges. Since the pesticides investigated are also anionic at the studied pH (7 and 8.3) the dissolved organics lead to the

  18. Mechanical characterization of filler sandcretes with rice husk ash additions. Study applied to Senegal

    SciTech Connect

    Cisse, I.K.; Laquerbe, M.

    2000-01-01

    To capitalize on the local materials of Senegal (agricultural and industrial wastes, residual fines from crushing process, sands from dunes, etc.), rise husk ash and residues of industrial and agricultural wastes have been used as additions in sandcretes. The mechanical resistance of sandcrete blocks obtained when unground ash (and notably the ground ash) is added reveals that there is an increase in performance over the classic mortar blocks. In addition, the use of unground rice husk ash enables production of a lightweight sandcrete with insulating properties, at a reduced cost. The ash pozzolanic reactivity explains the high strengths obtained.

  19. Comparative Study on the MDR Reversal Effects of Selected Chalcones

    PubMed Central

    Ivanova, A. B.; Batovska, D. I.; Todorova, I. T.; Stamboliyska, B. A.; Serly, J.; Molnar, J.

    2011-01-01

    Based on the structure of three previously established lead compounds, fifteen selected chalcones were synthesized and evaluated for their multidrug resistance (MDR) reversal activity on mouse lymphoma cells. The most active chalcones were stronger revertants than the positive control, verapamil. In the model of combination chemotherapy, the interactions between the anticancer drug doxorubicin and two of the most effective compounds were measured in vitro, on human MDR1 gene transfected mouse lymphoma cells, showing that the type of interaction for one of these compounds was indifferent while that for the other one was additive. Furthermore, two chalcones inhibited 50% of cell proliferation in concentration of around 0.4 μg/mL and were from 2- to 100-fold more active than the most chalcones. The structure-activity relationships were obtained and discussed in view of their usefulness for the design of chalcone-like P-gp modulators and drugs able to treat resistant cancers. PMID:27516904

  20. Comparative Study on the MDR Reversal Effects of Selected Chalcones.

    PubMed

    Ivanova, A B; Batovska, D I; Todorova, I T; Stamboliyska, B A; Serly, J; Molnar, J

    2011-01-01

    Based on the structure of three previously established lead compounds, fifteen selected chalcones were synthesized and evaluated for their multidrug resistance (MDR) reversal activity on mouse lymphoma cells. The most active chalcones were stronger revertants than the positive control, verapamil. In the model of combination chemotherapy, the interactions between the anticancer drug doxorubicin and two of the most effective compounds were measured in vitro, on human MDR1 gene transfected mouse lymphoma cells, showing that the type of interaction for one of these compounds was indifferent while that for the other one was additive. Furthermore, two chalcones inhibited 50% of cell proliferation in concentration of around 0.4 μg/mL and were from 2- to 100-fold more active than the most chalcones. The structure-activity relationships were obtained and discussed in view of their usefulness for the design of chalcone-like P-gp modulators and drugs able to treat resistant cancers. PMID:27516904

  1. Exploiting expert systems in cardiology: a comparative study.

    PubMed

    Economou, George-Peter K; Sourla, Efrosini; Stamatopoulou, Konstantina-Maria; Syrimpeis, Vasileios; Sioutas, Spyros; Tsakalidis, Athanasios; Tzimas, Giannis

    2015-01-01

    An improved Adaptive Neuro-Fuzzy Inference System (ANFIS) in the field of critical cardiovascular diseases is presented. The system stems from an earlier application based only on a Sugeno-type Fuzzy Expert System (FES) with the addition of an Artificial Neural Network (ANN) computational structure. Thus, inherent characteristics of ANNs, along with the human-like knowledge representation of fuzzy systems are integrated. The ANFIS has been utilized into building five different sub-systems, distinctly covering Coronary Disease, Hypertension, Atrial Fibrillation, Heart Failure, and Diabetes, hence aiding doctors of medicine (MDs), guide trainees, and encourage medical experts in their diagnoses centering a wide range of Cardiology. The Fuzzy Rules have been trimmed down and the ANNs have been optimized in order to focus into each particular disease and produce results ready-to-be applied to real-world patients. PMID:25417018

  2. Comparative study of analytical techniques for determining protein charge.

    PubMed

    Filoti, Dana I; Shire, Steven J; Yadav, Sandeep; Laue, Thomas M

    2015-07-01

    As interest in high-concentration protein formulations has increased, it has become apparent that routine, accurate protein charge measurements are necessary. There are several techniques for charge measurement, and a comparison of the methods is needed. The electrophoretic mobility, effective charge, and Debye-Hückel-Henry charge have been determined for bovine serum albumin, and human serum albumin. Three different electrophoretic methods were used to measure the electrophoretic mobility: capillary electrophoresis, electrophoretic light scattering, and membrane confined electrophoresis. In addition, the effective charge was measured directly using steady-state electrophoresis. Measurements made at different NaCl concentrations, pH, and temperatures allow comparison with previous charge estimates based on electrophoresis, Donnan equilibrium, and pH titration. Similar charge estimates are obtained by all of the methods. The strengths and limitations of each technique are discussed, as are some general considerations about protein charge and charge determination. PMID:25911989

  3. New approaches to the study of comparative cognition.

    PubMed

    Kesner, R P

    1990-01-01

    The rat's memory capacity and performance render it an excellent model of human memory. Rats display serial position, serial anticipation learning, temporal coding, and repetition lag functions as well as utilization of retrospective and prospective codes that are nearly equivalent to that observed for humans. Furthermore, based on the above-mentioned memory performance functions, there are comparable memory-deficit patterns between brain-damaged rats and humans. Thus, the rat can serve as an excellent animal model to evaluate the efficacy of pharmacological treatments or brain damage upon memory. PMID:2247138

  4. Comparative study of WLS fibres for the ATLAS Tile Calorimeter

    NASA Astrophysics Data System (ADS)

    Gomes, A.; David, M.; Henriques, A.; Maio, A.

    1998-02-01

    The Wave Length Shifting (WLS) fibres are one of the most important components of the ATLAS barrel hadronic tile calorimeter (Tilecal). The fibres collect the hght produced in the injection molded scintillating tiles and transport it to the photomultipliers. Parameters like attenuation length and light yield are important, as well as flexibility and radiation hardness. Comparative results of WLS fibres produced by Bicron, Kuraray and Pol.Hi.Tech are presented. The performance of the fibres BCF91A from Bicron and S048 from Pol.Hi.Tech was significatively improved, but the most performant are still the double clad Y11 fibres from Kuraray.

  5. Comparative study of WLS fibres for the ATLAS tile calorimeter

    NASA Astrophysics Data System (ADS)

    Gomes, A.; David, M.; Henriques, A.; Maio, A.

    1997-02-01

    The Wave Length Shifting (WLS) fibres are one of the most important components of the ATLAS barrel hadronic tile calorimeter (Tilecal). The fibres collect the light produced in the injection molded scintillating tiles and transport it to the photomultipliers. Parameters like attenuation length and light yield are important, as well as flexibility and radiation hardness. Comparative results of WLS fibres produced by Bicron, Kuraray and Pol.Hi.Tech are presented. The performance of the fibres BCF91A from Bicron and S048 from Pol.Hi.Tech was significatively improved, but the most performant are still the double clad Y11 fibres from Kuraray.

  6. Inconsistencies between two attosecond pulse metrology methods: A comparative study

    SciTech Connect

    Kruse, J. E.; Skantzakis, E.; Charalambidis, D.; Tzallas, P.; Kalpouzos, C.; Tsakiris, G. D.

    2010-08-15

    The two basic approaches underlying most of the metrology of attosecond pulse trains are compared in the spectral region {approx}14-24 eV, that is, the second-order intensity volume autocorrelation and the resolution of attosecond beating by interference of two photon transitions (RABITT). They give rather dissimilar pulse durations. It is concluded that for the present experimental conditions RABITT may underestimate the duration under measurement, due to variations of the driving intensity, but in conjunction with theory allows an estimation of the relative contributions of two different electron trajectories to the extreme-ultraviolet (XUV) radiation.

  7. Comparative study of solar optics for paraboloidal concentrators

    NASA Technical Reports Server (NTRS)

    Wen, L.; Poon, P.; Carley, W.; Huang, L.

    1979-01-01

    Different analytical methods for computing the flux distribution on the focal plane of a paraboloidal solar concentrator are reviewed. An analytical solution in algebraic form is also derived for an idealized model. The effects resulting from using different assumptions in the definition of optical parameters used in these methodologies are compared and discussed in detail. These parameters include solar irradiance distribution (limb darkening and circumsolar), reflector surface specular spreading, surface slope error, and concentrator pointing inaccuracy. The type of computational method selected for use depends on the maturity of the design and the data available at the time the analysis is made.

  8. Study on automatic optical element addition or deletion in lens optimization

    NASA Astrophysics Data System (ADS)

    Cheng, Xuemin; Wang, Yongtian; Hao, Qun

    2002-09-01

    Two lens form parameters, quantifying the symmetry of the optical system and the optical power distribution among the individual lens elements, are used as the criteria for automatic element addition or deletion in lens optimization. The scheme based on the criteria is described in this paper. Design examples are provided, which demonstrate that the scheme is practicable.

  9. Teaching Young Children Decomposition Strategies to Solve Addition Problems: An Experimental Study

    ERIC Educational Resources Information Center

    Cheng, Zi-Juan

    2012-01-01

    The ability to count has traditionally been considered an important milestone in children's development of number sense. However, using counting (e.g., counting on, counting all) strategies to solve addition problems is not the best way for children to achieve their full mathematical potential and to prepare them to develop more complex and…

  10. Vector generalized additive models for extreme rainfall data analysis (study case rainfall data in Indramayu)

    NASA Astrophysics Data System (ADS)

    Utami, Eka Putri Nur; Wigena, Aji Hamim; Djuraidah, Anik

    2016-02-01

    Rainfall pattern are good indicators for potential disasters. Global Circulation Model (GCM) contains global scale information that can be used to predict the rainfall data. Statistical downscaling (SD) utilizes the global scale information to make inferences in the local scale. Essentially, SD can be used to predict local scale variables based on global scale variables. SD requires a method to accommodate non linear effects and extreme values. Extreme value Theory (EVT) can be used to analyze the extreme value. One of methods to identify the extreme events is peak over threshold that follows Generalized Pareto Distribution (GPD). The vector generalized additive model (VGAM) is an extension of the generalized additive model. It is able to accommodate linear or nonlinear effects by involving more than one additive predictors. The advantage of VGAM is to handle multi response models. The key idea of VGAM are iteratively reweighted least square for maximum likelihood estimation, penalized smoothing, fisher scoring and additive models. This works aims to analyze extreme rainfall data in Indramayu using VGAM. The results show that the VGAM with GPD is able to predict extreme rainfall data accurately. The prediction in February is very close to the actual value at quantile 75.

  11. Studies on the Food Additive Propyl Gallate: Synthesis, Structural Characterization, and Evaluation of the Antioxidant Activity

    ERIC Educational Resources Information Center

    Garrido, Jorge; Garrido, E. Manuela; Borges, Fernanda

    2012-01-01

    Antioxidants are additives largely used in industry for delaying, retarding, or preventing the development of oxidative deterioration. Propyl gallate (E310) is a phenolic antioxidant extensively used in the food, cosmetics, and pharmaceutical industries. A series of lab experiments have been developed to teach students about the importance and…

  12. A comparative study of radiofrequency antennas for Helicon plasma sources

    NASA Astrophysics Data System (ADS)

    Melazzi, D.; Lancellotti, V.

    2015-04-01

    Since Helicon plasma sources can efficiently couple power and generate high-density plasma, they have received interest also as spacecraft propulsive devices, among other applications. In order to maximize the power deposited into the plasma, it is necessary to assess the performance of the radiofrequency (RF) antenna that drives the discharge, as typical plasma parameters (e.g. the density) are varied. For this reason, we have conducted a comparative analysis of three Helicon sources which feature different RF antennas, namely, the single-loop, the Nagoya type-III and the fractional helix. These antennas are compared in terms of input impedance and induced current density; in particular, the real part of the impedance constitutes a measure of the antenna ability to couple power into the plasma. The results presented in this work have been obtained through a full-wave approach which (being hinged on the numerical solution of a system of integral equations) allows computing the antenna current and impedance self-consistently. Our findings indicate that certain combinations of plasma parameters can indeed maximize the real part of the input impedance and, thus, the deposited power, and that one of the three antennas analyzed performs best for a given plasma. Furthermore, unlike other strategies which rely on approximate antenna models, our approach enables us to reveal that the antenna current density is not spatially uniform, and that a correlation exists between the plasma parameters and the spatial distribution of the current density.

  13. Comparative Study on Various Authentication Protocols in Wireless Sensor Networks.

    PubMed

    Rajeswari, S Raja; Seenivasagam, V

    2016-01-01

    Wireless sensor networks (WSNs) consist of lightweight devices with low cost, low power, and short-ranged wireless communication. The sensors can communicate with each other to form a network. In WSNs, broadcast transmission is widely used along with the maximum usage of wireless networks and their applications. Hence, it has become crucial to authenticate broadcast messages. Key management is also an active research topic in WSNs. Several key management schemes have been introduced, and their benefits are not recognized in a specific WSN application. Security services are vital for ensuring the integrity, authenticity, and confidentiality of the critical information. Therefore, the authentication mechanisms are required to support these security services and to be resilient to distinct attacks. Various authentication protocols such as key management protocols, lightweight authentication protocols, and broadcast authentication protocols are compared and analyzed for all secure transmission applications. The major goal of this survey is to compare and find out the appropriate protocol for further research. Moreover, the comparisons between various authentication techniques are also illustrated. PMID:26881272

  14. Beyond EUV lithography: a comparative study of efficient photoresists' performance

    PubMed Central

    Mojarad, Nassir; Gobrecht, Jens; Ekinci, Yasin

    2015-01-01

    Extreme ultraviolet (EUV) lithography at 13.5 nm is the main candidate for patterning integrated circuits and reaching sub-10-nm resolution within the next decade. Should photon-based lithography still be used for patterning smaller feature sizes, beyond EUV (BEUV) lithography at 6.x nm wavelength is an option that could potentially meet the rigid demands of the semiconductor industry. We demonstrate simultaneous characterization of the resolution, line-edge roughness, and sensitivity of distinct photoresists at BEUV and compare their properties when exposed to EUV under the same conditions. By using interference lithography at these wavelengths, we show the possibility for patterning beyond 22 nm resolution and characterize the impact of using higher energy photons on the line-edge roughness and exposure latitude. We observe high sensitivity of the photoresist performance on its chemical content and compare their overall performance using the Z-parameter criterion. Interestingly, inorganic photoresists have much better performance at BEUV, while organic chemically-amplified photoresists would need serious adaptations for being used at such wavelength. Our results have immediate implications for deeper understanding of the radiation chemistry of novel photoresists at the EUV and soft X-ray spectra. PMID:25783209

  15. Comparative Study on Various Authentication Protocols in Wireless Sensor Networks

    PubMed Central

    Rajeswari, S. Raja; Seenivasagam, V.

    2016-01-01

    Wireless sensor networks (WSNs) consist of lightweight devices with low cost, low power, and short-ranged wireless communication. The sensors can communicate with each other to form a network. In WSNs, broadcast transmission is widely used along with the maximum usage of wireless networks and their applications. Hence, it has become crucial to authenticate broadcast messages. Key management is also an active research topic in WSNs. Several key management schemes have been introduced, and their benefits are not recognized in a specific WSN application. Security services are vital for ensuring the integrity, authenticity, and confidentiality of the critical information. Therefore, the authentication mechanisms are required to support these security services and to be resilient to distinct attacks. Various authentication protocols such as key management protocols, lightweight authentication protocols, and broadcast authentication protocols are compared and analyzed for all secure transmission applications. The major goal of this survey is to compare and find out the appropriate protocol for further research. Moreover, the comparisons between various authentication techniques are also illustrated. PMID:26881272

  16. Strategy Maps in University Management: A Comparative Study

    ERIC Educational Resources Information Center

    Han, Shuangmiao; Zhong, Zhou

    2015-01-01

    In this study, the conceptual use of the strategy map approach and the strategy map which it produces have been adapted from the business sector and introduced as tools for achieving more effective strategic planning and management in higher education institutions (HEIs). This study discusses the development of strategy maps as transformational…

  17. Civic and Citizenship Education in 2009 (ICCS): A Comparative Study

    ERIC Educational Resources Information Center

    Schulz, Wolfram; Ainley, John

    2007-01-01

    The purpose of the "International Civic and Citizenship Education Study" (ICCS) is to investigate the ways in which young people are prepared to undertake their roles as citizens in a range of countries. The study will report on student achievement on a test of conceptual understandings and competencies in civic and citizenship education. It will…

  18. The Earmarks of College Success: A Causal-Comparative Study.

    ERIC Educational Resources Information Center

    Wisconsin Univ., Stevens Point. Office of Institutional Research.

    This study delineates characteristics related to suspended, probation, and nonprobation college students. The population of sub-population studies are composed of 1971-72 undergraduates at the University of Wisconsin-Stevens Point, and for some parts the entering freshmen for only 1971-72. By the end of the school year, all students were…

  19. Students' Perceptions of Online Learning: A Comparative Study

    ERIC Educational Resources Information Center

    Smart, Karl L.; Cappel, James J.

    2006-01-01

    In search of better, more cost effective ways to deliver instruction and training, universities and corporations have expanded their use of e-learning. Although several studies suggest that online education and blended instruction (a "blend" of online and traditional approaches) can be as effective as traditional classroom models, few studies have…

  20. "Mistakes Are a Fact of Life": A National Comparative Study

    ERIC Educational Resources Information Center

    Lunsford, Andrea A.; Lunsford, Karen J.

    2008-01-01

    This essay reports on a study of first-year student writing. Based on a stratified national sample, the study attempts to replicate research conducted twenty-two years ago and to chart the changes that have taken place in student writing since then. The findings suggest that papers are longer, employ different genres, and contain new error…

  1. Comparing International Curriculum Systems: The International Instructional Systems Study

    ERIC Educational Resources Information Center

    Creese, Brian; Gonzalez, Alvaro; Isaacs, Tina

    2016-01-01

    This paper sets out the main findings of the International Instructional Systems Study (IISS), conducted by the UCL Institute of Education and funded by the Center on International Education Benchmarking (CIEB). The study examined the instructional systems and intended curricula of six "high performing" countries and two US states. The…

  2. Tribal College and University Accreditation: A Comparative Study.

    ERIC Educational Resources Information Center

    Putman, T. Elizabeth Mennell

    In the context of tribal colleges, accreditation is a complex issue. This study, which is a replication of a study by J. McDonald in 1982, is an examination of how the perceptions of tribal college faculty, staff, and governing board members toward the importance and impact of accreditation have changed since 1982. Surveys were administered to the…

  3. Asperger Syndrome and Schizophrenia: A Comparative Neuropsychological Study

    ERIC Educational Resources Information Center

    Marinopoulou, Maria; Lugnegård, Tove; Unenge Hallerbäck, Maria; Gillberg, Christopher; Billstedt, Eva

    2016-01-01

    There has been an increasing interest in possible connections between autism spectrum disorder (ASD) and schizophrenia in the last decade. Neuropsychological comparison studies have, however, been few. The present study examined similarities and differences in intellectual and executive functioning between adults with Asperger syndrome (AS) and…

  4. Metafunctional Practices in Medical Research Articles: A Comparative Study

    ERIC Educational Resources Information Center

    Assadi, Nader; Ghassemi, Mojtaba; Madadi, Alireza

    2014-01-01

    The purpose of this study is to explore any possible difference among the verb types chosen in articles written in English by the non-natives and natives. In so doing, Halliday's Systemic Functional Grammar (1994) was employed. 80 published articles from the medical sciences field of study were chosen from among which 40 were written by native…

  5. Study on Lexical Cohesion in English and Persian Research Articles (A Comparative Study)

    ERIC Educational Resources Information Center

    Mirzapour, Fatemeh; Ahmadi, Maryam

    2011-01-01

    The present study aims to analyze comparatively English and Persian research articles (Linguistics, Literature, and Library and Information disciplines) in terms of number and degree of utilization of sub-types of lexical cohesion in order to appreciate textualization processes in the two languages concerned. The study analyzes 60 research…

  6. A critique of comparative studies of brain size

    PubMed Central

    Healy, Susan D; Rowe, Candy

    2006-01-01

    In recent years, there have been over 50 comparative analyses carried out in which social or ecological variables have been used to explain variation in whole brain size, or a part thereof, in a range of vertebrate species. Here, we review this body of work, pointing out that there are a number of substantial problems with some of the assumptions that underpin the hypotheses (e.g. what brain size means), with the data collection and with the ways in which the data are combined in the analyses. These problems are particularly apparent in those analyses in which attempts are made to correlate complex behaviour with parts of the brain that carry out multiple functions. We conclude that now is the time to substantiate these results with data from experimental manipulations. PMID:17476764

  7. Leptin in Teleost Fishes: An Argument for Comparative Study

    PubMed Central

    Copeland, Donald L.; Duff, Robert Joel; Liu, Qin; Prokop, Jeremy; Londraville, Richard Lyle

    2011-01-01

    All organisms face tradeoffs with regard to how limited energy resources should be invested. When is it most favorable to grow, to reproduce, how much lipid should be allocated to storage in preparation for a period of limited resources (e.g., winter), instead of being used for growth or maturation? These are a few of the high consequence fitness “decisions” that represent the balance between energy acquisition and allocation. Indeed, for animals to make favorable decisions about when to grow, eat, or reproduce, they must integrate signals among the systems responsible for energy acquisition, storage, and demand. We make the argument that leptin signaling is a likely candidate for an integrating system. Great progress has been made understanding the leptin system in mammals, however our understanding in fishes has been hampered by difficulty in cloning fish orthologs of mammalian proteins and (we assert), underutilization of the comparative approach. PMID:21716655

  8. Comparative Study of the Thermal Conductivity of Solid Biomass Fuels

    PubMed Central

    2016-01-01

    The thermal conductivity of solid biomass fuels is useful information in the investigation of biomass combustion behavior and the development of modeling especially in the context of large scale power generation. There are little published data on the thermal conductivity of certain types of biomass such as wheat straw, miscanthus, and torrefied woods. Much published data on wood is in the context of bulk materials. A method for determining the thermal conductivities of small particles of biomass fuels has been developed using a custom built test apparatus. Fourteen different samples of various solid biomass fuel were processed to form a homogenized pellet for analysis. The thermal conductivities of the pelletized materials were determined and compared against each other and to existing data. PMID:27041819

  9. [Comparative study of immunomodulating properties of phenibut and gammoxin].

    PubMed

    Tiurenkov, I N; Samotrueva, M A; Kuleshevskaia, N R; Berestovitskaia, V M; Vasil'eva, O S

    2010-12-01

    Experiments on CBA mice with model immunodepression induced by cyclophosphamide showed that phenibut (25 mg/kg) and gammoxin (25 mg/kg) recover both cellular and humoral immunoreactivity and restore lymphoproliferative processes in immunocompetent organs, which is evidence for pronounced immunocorrecting properties of these drugs. A comparative analysis of the immunomodulating activity of phenibut and gammoxin showed that the latter drug predominantly affects the process of immunocompetent cell maturation (growth in mass and cellularity of thymus and spleen--the central immunocompetent organs), while phenibut mostly influences the realization of the final reaction of the primary anti-erythrocyte immune response (significant correction of local infiltration delayed-type hypersensitivity reaction and antibody formation). This difference can be related to the fact that the drugs influence GABA receptors of different types, whereby gammoxin acts on these receptors in immunocompetent organs and phenibut acts on the receptors in lymphocytes. PMID:21395013

  10. A comparative study of SAR data compression schemes

    NASA Technical Reports Server (NTRS)

    Lambert-Nebout, C.; Besson, O.; Massonnet, D.; Rogron, B.

    1994-01-01

    The amount of data collected from spaceborne remote sensing has substantially increased in the last years. During same time period, the ability to store or transmit data has not increased as quickly. At this time, there is a growing interest in developing compression schemes that could provide both higher compression ratios and lower encoding/decoding errors. In the case of the spaceborne Synthetic Aperture Radar (SAR) earth observation system developed by the French Space Agency (CNES), the volume of data to be processed will exceed both the on-board storage capacities and the telecommunication link. The objective of this paper is twofold: to present various compression schemes adapted to SAR data; and to define a set of evaluation criteria and compare the algorithms on SAR data. In this paper, we review two classical methods of SAR data compression and propose novel approaches based on Fourier Transforms and spectrum coding.

  11. A comparative study of computational methods in cosmic gas dynamics

    NASA Technical Reports Server (NTRS)

    Van Albada, G. D.; Van Leer, B.; Roberts, W. W., Jr.

    1982-01-01

    Many theoretical investigations of fluid flows in astrophysics require extensive numerical calculations. The selection of an appropriate computational method is, therefore, important for the astronomer who has to solve an astrophysical flow problem. The present investigation has the objective to provide an informational basis for such a selection by comparing a variety of numerical methods with the aid of a test problem. The test problem involves a simple, one-dimensional model of the gas flow in a spiral galaxy. The numerical methods considered include the beam scheme, Godunov's method (G), the second-order flux-splitting method (FS2), MacCormack's method, and the flux corrected transport methods of Boris and Book (1973). It is found that the best second-order method (FS2) outperforms the best first-order method (G) by a huge margin.

  12. Assessing Holland Types on the Internet: A Comparative Study

    ERIC Educational Resources Information Center

    Miller, Mark J.; Cowger, Ernest, Jr.; Young, Tony; Tobacyk, Jerome; Sheets, Tillman; Loftus, Christina

    2008-01-01

    This study examined the degree of similarity between scores on the Self-Directed Search and an online instrument measuring Holland types. A relatively high congruency score was found between the two measures. Implications for career counselors are discussed.

  13. Neuropathology of HIV infection in haemophiliacs: comparative necropsy study.

    PubMed Central

    Esiri, M. M.; Scaravilli, F.; Millard, P. R.; Harcourt-Webster, J. N.

    1989-01-01

    OBJECTIVE--To discover whether pathological and neuropathological findings at necropsy are different in haemophiliacs and other subjects positive for HIV. DESIGN--Pathological and neuropathological findings at necropsy were compared in haemophiliacs and non-haemophiliacs, most of them homosexual men. SETTING--Necropsies performed in the south of England. SUBJECTS--11 Haemophiliacs (mean age 41, range 15-69) and 31 non-haemophiliacs, 29 of whom were homosexual men (mean age 40, range 21-60). AIDS was diagnosed before death in four haemophiliacs and all but one of the non-haemophiliacs. MAIN OUTCOME MEASURES--Prevalence of various forms of neuropathology and systemic pathology in the haemophiliacs and non-haemophiliacs, compared with Fisher's exact test. RESULTS--The prevalences of opportunistic infections of the central nervous system were significantly higher in the non-haemophiliacs (cerebral toxoplasmosis 23% (7), progressive multifocal leucoencephalopathy 10% (3), and cerebral cytomegalovirus infection 19% (6) in the non-haemophiliacs v no cases in the haemophiliacs). The prevalences of fresh and old intracranial haemorrhages and cirrhosis of the liver were significantly higher in the haemophiliacs (fresh intracranial haemorrhage 45% (5), old intracranial haemorrhage 36% (4), and cirrhosis of the liver 27% (3) in the haemophiliacs v no cases in the non-haemophiliacs). The prevalence of neuropathological changes in the non-haemophiliacs was similar to that found in other necropsy series. CONCLUSIONS--The main causes of death in haemophiliacs positive for HIV included intracranial haemorrhage and cirrhosis of the liver. The haemophiliacs died when the characteristic neuropathological changes associated with HIV infection were at a fairly early stage in their development. PMID:2513933

  14. Comparative study of ion conducting pathways in borate glasses

    SciTech Connect

    Hall, Andreas; Swenson, Jan; Adams, Stefan

    2006-11-01

    The conduction pathways in metal-halide doped silver, lithium, and sodium diborate glasses have been examined by bond valence analysis of reverse Monte Carlo (RMC) produced structural models of the glasses. Although all glass compositions have basically the same short-range structure of the boron-oxygen network, it is evident that the intermediate-range structure is strongly dependent on the type of mobile ion. The topography of the pathways and the coordination of the pathway sites differ distinctly between the three glass systems. The mobile silver ions in the AgI-doped glass tend to be mainly iodine-coordinated and travel in homogeneously distributed pathways located in salt-rich channels of the borate network. In the NaCl-doped glass, there is an inhomogeneous spatial distribution of pathways that reflects the inhomogeneous introduction of salt ions into the glass. However, since the salt clusters are not connected, no long-range conduction pathways are formed without including also oxygen-rich regions. The pathways in the LiCl-doped glass are slightly more evenly distributed compared to the NaCl-doped glass (but not as ordered as in the AgI-doped glass), and the regions of mainly oxygen-coordinated pathway sites are of higher importance for the long-range migration. In order to more accurately investigate how these differences in the intermediate-range order of the glasses affect the ionic conductivity, we have compared the realistic structure models to more or less randomized structures. An important conclusion from this comparison is that we find no evidence that a pronounced intermediate-range order in the atomic structure or in the network of conduction pathways, as in the AgI-doped glass, is beneficial for the dc conductivity.

  15. Priority Questions and Horizon Scanning for Conservation: A Comparative Study

    PubMed Central

    Kark, Salit; Sutherland, William J.; Shanas, Uri; Klass, Keren; Achisar, Hila; Dayan, Tamar; Gavrieli, Yael; Justo-Hanani, Ronit; Mandelik, Yael; Orion, Nir; Pargament, David; Portman, Michelle; Reisman-Berman, Orna; Safriel, Uriel N.; Schaffer, Gad; Steiner, Noa; Tauber, Israel; Levin, Noam

    2016-01-01

    Several projects aimed at identifying priority issues for conservation with high relevance to policy have recently been completed in several countries. Two major types of projects have been undertaken, aimed at identifying (i) policy-relevant questions most imperative to conservation and (ii) horizon scanning topics, defined as emerging issues that are expected to have substantial implications for biodiversity conservation and policy in the future. Here, we provide the first overview of the outcomes of biodiversity and conservation-oriented projects recently completed around the world using this framework. We also include the results of the first questions and horizon scanning project completed for a Mediterranean country. Overall, the outcomes of the different projects undertaken (at the global scale, in the UK, US, Canada, Switzerland and in Israel) were strongly correlated in terms of the proportion of questions and/or horizon scanning topics selected when comparing different topic areas. However, some major differences were found across regions. There was large variation among regions in the percentage of proactive (i.e. action and response oriented) versus descriptive (non-response oriented) priority questions and in the emphasis given to socio-political issues. Substantial differences were also found when comparing outcomes of priority questions versus horizon scanning projects undertaken for the same region. For example, issues related to climate change, human demography and marine ecosystems received higher priority as horizon scanning topics, while ecosystem services were more emphasized as current priority questions. We suggest that future initiatives aimed at identifying priority conservation questions and horizon scanning topics should allow simultaneous identification of both current and future priority issues, as presented here for the first time. We propose that further emphasis on social-political issues should be explicitly integrated into future

  16. Priority Questions and Horizon Scanning for Conservation: A Comparative Study.

    PubMed

    Kark, Salit; Sutherland, William J; Shanas, Uri; Klass, Keren; Achisar, Hila; Dayan, Tamar; Gavrieli, Yael; Justo-Hanani, Ronit; Mandelik, Yael; Orion, Nir; Pargament, David; Portman, Michelle; Reisman-Berman, Orna; Safriel, Uriel N; Schaffer, Gad; Steiner, Noa; Tauber, Israel; Levin, Noam

    2016-01-01

    Several projects aimed at identifying priority issues for conservation with high relevance to policy have recently been completed in several countries. Two major types of projects have been undertaken, aimed at identifying (i) policy-relevant questions most imperative to conservation and (ii) horizon scanning topics, defined as emerging issues that are expected to have substantial implications for biodiversity conservation and policy in the future. Here, we provide the first overview of the outcomes of biodiversity and conservation-oriented projects recently completed around the world using this framework. We also include the results of the first questions and horizon scanning project completed for a Mediterranean country. Overall, the outcomes of the different projects undertaken (at the global scale, in the UK, US, Canada, Switzerland and in Israel) were strongly correlated in terms of the proportion of questions and/or horizon scanning topics selected when comparing different topic areas. However, some major differences were found across regions. There was large variation among regions in the percentage of proactive (i.e. action and response oriented) versus descriptive (non-response oriented) priority questions and in the emphasis given to socio-political issues. Substantial differences were also found when comparing outcomes of priority questions versus horizon scanning projects undertaken for the same region. For example, issues related to climate change, human demography and marine ecosystems received higher priority as horizon scanning topics, while ecosystem services were more emphasized as current priority questions. We suggest that future initiatives aimed at identifying priority conservation questions and horizon scanning topics should allow simultaneous identification of both current and future priority issues, as presented here for the first time. We propose that further emphasis on social-political issues should be explicitly integrated into future

  17. Comparative Biochemical and Immunological Studies of Bacterial Glutamine Synthetases

    PubMed Central

    Tronick, Steven R.; Ciardi, Joseph E.; Stadtman, E. R.

    1973-01-01

    Antisera prepared against adenylylated and unadenylylated Escherichia coli glutamine synthetase cross-reacted with the glutamine synthetases from a number of gram-negative bacteria and one gram-variable species as demonstrated by immunodiffusion and inhibition of enzyme activity. In contrast, the antisera did not cross-react with the glutamine synthetases from gram-positive bacteria (with one exception) nor with the synthetases of higher organisms. Modification of the various glutamine synthetases by covalent attachment of adenosine 5′-monophosphate (or other nucleotides) was tested for by determining whether or not snake venom phosphodiesterase altered catalytic activity in a manner similar to its effect on adenylylated E. coli glutamine synthetase. Only the activity of the glutamine synthetases from gram-negative bacteria grown with specific levels of nitrogen sources could be altered by snake venom phosphodiesterase. In addition, a relative order of antigenic homology between cross-reacting enzymes was suggested based on the patterns of spur formation in the immunodiffusion assay. Images PMID:4125585

  18. A Comparative Study of Interval Management Control Law Capabilities

    NASA Technical Reports Server (NTRS)

    Barmore, Bryan E.; Smith, Colin L.; Palmer, Susan O.; Abbott, Terence S.

    2012-01-01

    This paper presents a new tool designed to allow for rapid development and testing of different control algorithms for airborne spacing. This tool, Interval Management Modeling and Spacing Tool (IM MAST), is a fast-time, low-fidelity tool created to model the approach of aircraft to a runway, with a focus on their interactions with each other. Errors can be induced between pairs of aircraft by varying initial positions, winds, speed profiles, and altitude profiles. Results to-date show that only a few of the algorithms tested had poor behavior in the arrival and approach environment. The majority of the algorithms showed only minimal variation in performance under the test conditions. Trajectory-based algorithms showed high susceptibility to wind forecast errors, while performing marginally better than the other algorithms under other conditions. Trajectory-based algorithms have a sizable advantage, however, of being able to perform relative spacing operations between aircraft on different arrival routes and flight profiles without employing ghosting. methods. This comes at the higher cost of substantially increased complexity, however. Additionally, it was shown that earlier initiation of relative spacing operations provided more time for corrections to be made without any significant problems in the spacing operation itself. Initiating spacing farther out, however, would require more of the aircraft to begin spacing before they merge onto a common route.

  19. A Comparative Study of Co-Channel Interference Suppression Techniques

    NASA Technical Reports Server (NTRS)

    Hamkins, Jon; Satorius, Ed; Paparisto, Gent; Polydoros, Andreas

    1997-01-01

    We describe three methods of combatting co-channel interference (CCI): a cross-coupled phase-locked loop (CCPLL); a phase-tracking circuit (PTC), and joint Viterbi estimation based on the maximum likelihood principle. In the case of co-channel FM-modulated voice signals, the CCPLL and PTC methods typically outperform the maximum likelihood estimators when the modulation parameters are dissimilar. However, as the modulation parameters become identical, joint Viterbi estimation provides for a more robust estimate of the co-channel signals and does not suffer as much from "signal switching" which especially plagues the CCPLL approach. Good performance for the PTC requires both dissimilar modulation parameters and a priori knowledge of the co-channel signal amplitudes. The CCPLL and joint Viterbi estimators, on the other hand, incorporate accurate amplitude estimates. In addition, application of the joint Viterbi algorithm to demodulating co-channel digital (BPSK) signals in a multipath environment is also discussed. It is shown in this case that if the interference is sufficiently small, a single trellis model is most effective in demodulating the co-channel signals.

  20. ICMSF methods studies. VIII. Comparative study for the enumeration of Clostridium perfringens in foods.

    PubMed

    Hauschild, A H; Gilbert, R J; Harmon, S M; O'Keeffe, M F; Vahlefeld, R

    1977-07-01

    Four methods were compared in an international comparative study for the enumeration of Clostridium perfringens: the SFP (Shahidi-Ferguson perfringens) agar (A), TSC (tryptose-sulfite-cycloserin) agar (B), SC (sulfite-cycloserine) agar (C), and neomycin blood agar (D) methods. The confirmed C. perfringens counts were slightly lower for D than for A-C. The percentages of presumptive colonies confirmed as C. perfringens were essentially the same in each method. The relative numbers of nonspecific colonies were the lowest in C, followed by B, D, and A. The methods were also compared for simplicity and for aspects associated with the recognition and selection of presumptive colonies. PMID:195698

  1. A laboratory study of the perceived benefit of additional noise attenuation by houses

    NASA Technical Reports Server (NTRS)

    Flindell, I. H.

    1983-01-01

    Two Experiments were conducted to investigate the perceived benefit of additional house attenuation against aircraft flyover noise. First, subjects made annoyance judgments in a simulated living room while an operative window with real and dummy storm windows was manipulated in full view of those subjects. Second, subjects made annoyance judgments in an anechoic audiometric test chamber of frequency shaped noise signals having spectra closely matched to those of the aircraft flyover noises reproduced in the first experiment. These stimuli represented the aircraft flyover noises in levels and spectra but without the situational and visual cues present in the simulated living room. Perceptual constancy theory implies that annoyance tends to remain constant despite reductions in noise level caused by additional attenuation of which the subjects are fully aware. This theory was supported when account was taken for a reported annoyance overestimation for certain spectra and for a simulated condition cue overreaction.

  2. Enhanced flux pinning in MOCVD-YBCO films through Zr-additions:Systematic feasibility studies

    SciTech Connect

    Aytug, Tolga; Paranthaman, Mariappan Parans; Specht, Eliot D; Kim, Kyunghoon; Zhang, Yifei; Cantoni, Claudia; Zuev, Yuri L; Goyal, Amit; Christen, David K; Maroni, Victor A.

    2009-01-01

    Systematic effects of Zr additions on the structural and flux pinning properties of YBa{sub 2}Cu{sub 3}O{sub 7-{delta}} (YBCO) films deposited by metal-organic chemical vapor deposition (MOCVD) have been investigated. Detailed characterization, conducted by coordinated transport, x-ray diffraction, scanning and transmission electron microscopy analyses, and imaging Raman microscopy have revealed trends in the resulting property/performance correlations of these films with respect to varying mole percentages (mol%) of added Zr. For compositions {le} 7.5 mol%, Zr additions lead to improved in-field critical current density, as well as extra correlated pinning along the c-axis direction of the YBCO films via the formation of columnar, self-assembled stacks of BaZrO{sub 3} nanodots.

  3. Enhanced flux pinning in MOCVD-YBCO films through Zr additions : systematic feasibility studies.

    SciTech Connect

    Aytug, T.; Paranthaman, M.; Specht, E. D.; Zhang, Y.; Kim, K.; Zuev, Y. L.; Cantoni, C.; Goyal, A.; Christen, D. K.; Maroni, V. A.; Chen, Y.; Selvamanickam, V.; ORNL; SuperPower, Inc.

    2010-01-01

    Systematic effects of Zr additions on the structural and flux pinning properties of YBa{sub 2}Cu{sub 3}O{sub 7-{delta}} (YBCO) films deposited by metal-organic chemical vapor deposition (MOCVD) have been investigated. Detailed characterization, conducted by coordinated transport, x-ray diffraction, scanning and transmission electron microscopy analyses, and imaging Raman microscopy have revealed trends in the resulting property/performance correlations of these films with respect to varying mole percentages (mol%) of added Zr. For compositions {le} 7.5 mol%, Zr additions lead to improved in-field critical current density, as well as extra correlated pinning along the c-axis direction of the YBCO films via the formation of columnar, self-assembled stacks of BaZrO{sub 3} nanodots.

  4. Indolyne Experimental and Computational Studies: Synthetic Applications and Origins of Selectivities of Nucleophilic Additions

    PubMed Central

    Im, G-Yoon J.; Bronner, Sarah M.; Goetz, Adam E.; Paton, Robert S.; Cheong, Paul H.-Y.; Houk, K. N.; Garg, Neil K.

    2010-01-01

    Efficient syntheses of 4,5-, 5,6-, and 6,7-indolyne precursors beginning from commercially available hydroxyindole derivatives are reported. The synthetic routes are versatile and allow access to indolyne precursors that remain unsubstituted on the pyrrole ring. Indolynes can be generated under mild fluoride-mediated conditions, trapped by a variety of nucleophilic reagents, and used to access a number of novel substituted indoles. Nucleophilic addition reactions to indolynes proceed with varying degrees of regioselectivity; distortion energies control regioselectivity and provide a simple model to predict the regioselectivity in the nucleophilic additions to indolynes and other unsymmetrical arynes. This model has led to the design of a substituted 4,5-indolyne that exhibits enhanced nucleophilic regioselectivity. PMID:21114321

  5. Structural changes in gluten protein structure after addition of emulsifier. A Raman spectroscopy study

    NASA Astrophysics Data System (ADS)

    Ferrer, Evelina G.; Gómez, Analía V.; Añón, María C.; Puppo, María C.

    2011-06-01

    Food protein product, gluten protein, was chemically modified by varying levels of sodium stearoyl lactylate (SSL); and the extent of modifications (secondary and tertiary structures) of this protein was analyzed by using Raman spectroscopy. Analysis of the Amide I band showed an increase in its intensity mainly after the addition of the 0.25% of SSL to wheat flour to produced modified gluten protein, pointing the formation of a more ordered structure. Side chain vibrations also confirmed the observed changes.

  6. A design study for the addition of higher order parametric discrete elements to NASTRAN

    NASA Technical Reports Server (NTRS)

    Stanton, E. L.

    1972-01-01

    The addition of discrete elements to NASTRAN poses significant interface problems with the level 15.1 assembly modules and geometry modules. Potential problems in designing new modules for higher-order parametric discrete elements are reviewed in both areas. An assembly procedure is suggested that separates grid point degrees of freedom on the basis of admissibility. New geometric input data are described that facilitate the definition of surfaces in parametric space.

  7. Load bearing and stiffness tailored NiTi implants produced by additive manufacturing: a simulation study

    NASA Astrophysics Data System (ADS)

    Rahmanian, Rasool; Shayesteh Moghaddam, Narges; Haberland, Christoph; Dean, David; Miller, Michael; Elahinia, Mohammad

    2014-03-01

    Common metals for stable long-term implants (e.g. stainless steel, Titanium and Titanium alloys) are much stiffer than spongy cancellous and even stiffer than cortical bone. When bone and implant are loaded this stiffness mismatch results in stress shielding and as a consequence, degradation of surrounding bony structure can lead to disassociation of the implant. Due to its lower stiffness and high reversible deformability, which is associated with the superelastic behavior, NiTi is an attractive biomaterial for load bearing implants. However, the stiffness of austenitic Nitinol is closer to that of bone but still too high. Additive manufacturing provides, in addition to the fabrication of patient specific implants, the ability to solve the stiffness mismatch by adding engineered porosity to the implant. This in turn allows for the design of different stiffness profiles in one implant tailored to the physiological load conditions. This work covers a fundamental approach to bring this vision to reality. At first modeling of the mechanical behavior of different scaffold designs are presented as a proof of concept of stiffness tailoring. Based on these results different Nitinol scaffolds can be produced by additive manufacturing.

  8. Magnetic Force Microscopy Study of Zr2Co11 -Based Nanocrystalline Materials: Effect of Mo Addition

    DOE PAGESBeta

    Yue, Lanping; Jin, Yunlong; Zhang, Wenyong; Sellmyer, David J.

    2015-01-01

    Tmore » he addition of Molybdenum was used to modify the nanostructure and enhance coercivity of rare-earth-free Zr2Co11-based nanocrystalline permanent magnets. he effect of Mo addition on magnetic domain structures of melt spun nanocrystalline Zr16Co84-xMox(x=0, 0.5, 1, 1.5, and 2.0) ribbons has been investigated. It was found that magnetic properties and local domain structures are strongly influenced by Mo doping. he coercivity of the samples increases with the increase in Mo content (x≤1.5). he maximum energy product(BH)maxincreases with increasingxfrom 0.5 MGOe forx=0to a maximum value of 4.2 MGOe forx=1.5. he smallest domain size with a relatively short magnetic correlation length of 128 nm and largest root-mean-square phase shiftΦrmsvalue of 0.66° are observed for thex=1.5. he optimal Mo addition promotes magnetic domain structure refinement and thus leads to a significant increase in coercivity and energy product in this sample.« less

  9. A Comparative Study of Aerocapture Missions with a Mars Destination

    NASA Technical Reports Server (NTRS)

    Vaughan, Diane; Miller, Heather C.; Griffin, Brand; James, Bonnie F.; Munk, Michelle M.

    2005-01-01

    Conventional interplanetary spacecraft use propulsive systems to decelerate into orbit. Aerocapture is an alternative approach for orbit capture, in which the spacecraft makes a single pass through a target destination's atmosphere. Although this technique has never been performed, studies show there are substantial benefits of using aerocapture for reduction of propellant mass, spacecraft size, and mission cost. The In-Space Propulsion (ISP) Program, part of NASA's Science Mission Directorate, has invested in aerocapture technology development since 2002. Aerocapture investments within ISP are largely driven by mission systems analysis studies, The purpose of this NASA-funded report is to identify and document the fundamental parameters of aerocapture within previous human and robotic Mars mission studies which will assist the community in identifying technology research gaps in human and robotic missions, and provide insight for future technology investments. Upon examination of the final data set, some key attributes within the aerocapture disciplines are identified.

  10. Parameters and pitfalls to consider in the conduct of food additive research, Carrageenan as a case study.

    PubMed

    Weiner, Myra L

    2016-01-01

    This paper provides guidance on the conduct of new in vivo and in vitro studies on high molecular weight food additives, with carrageenan, the widely used food additive, as a case study. It is important to understand the physical/chemical properties and to verify the identity/purity, molecular weight and homogeneity/stability of the additive in the vehicle for oral delivery. The strong binding of CGN to protein in rodent chow or infant formula results in no gastrointestinal tract exposure to free CGN. It is recommended that doses of high Mw non-caloric, non-nutritive additives not exceed 5% by weight of total solid diet to avoid potential nutritional effects. Addition of some high Mw additives at high concentrations to liquid nutritional supplements increases viscosity and may affect palatability, caloric intake and body weight gain. In in vitro studies, the use of well-characterized, relevant cell types and the appropriate composition of the culture media are necessary for proper conduct and interpretation. CGN is bound to media protein and not freely accessible to cells in vitro. Interpretation of new studies on food additives should consider the interaction of food additives with the vehicle components and the appropriateness of the animal or cell model and dose-response. PMID:26615870

  11. Reductive nitrosylation of Methanosarcina acetivorans protoglobin: A comparative study

    SciTech Connect

    Ascenzi, Paolo; Pesce, Alessandra; Nardini, Marco; Bolognesi, Martino; Ciaccio, Chiara; Coletta, Massimo; Dewilde, Sylvia

    2013-01-25

    Highlights: ► Methanosarcina acetivorans is a strictly anaerobic non-motile methane-producing Archaea. ► M. acetivorans protoglobin binds preferentially O{sub 2} rather than CO. ► Reductive nitrosylation of ferric M. acetivorans protoglobin. ► Nitrosylation of ferrious M. acetivorans protoglobin. ► M. acetivorans protoglobin is a scavenger of RNS and ROS. -- Abstract: Methanosarcina acetivorans is a strictly anaerobic non-motile methane-producing Archaea expressing protoglobin (Pgb) which might either facilitate O{sub 2} detoxification or act as a CO sensor/supplier in methanogenesis. Unusually, M. acetivorans Pgb (MaPgb) binds preferentially O{sub 2} rather than CO and displays anticooperativity in ligand binding. Here, kinetics and/or thermodynamics of ferric and ferrous MaPgb (MaPgb(III) and MaPgb(II), respectively) nitrosylation are reported. Data were obtained between pH 7.2 and 9.5, at 22.0 °C. Addition of NO to MaPgb(III) leads to the transient formation of MaPgb(III)–NO in equilibrium with MaPgb(II)–NO{sup +}. In turn, MaPgb(II)–NO{sup +} is converted to MaPgb(II) by OH{sup −}-based catalysis. Then, MaPgb(II) binds NO very rapidly leading to MaPgb(II)–NO. The rate-limiting step for reductive nitrosylation of MaPgb(III) is represented by the OH{sup −}-mediated reduction of MaPgb(II)–NO{sup +} to MaPgb(II). Present results highlight the potential role of MaPgb in scavenging of reactive nitrogen and oxygen species.

  12. [Comparative study on eight trace elements in twelve flower medicines].

    PubMed

    Niu, Ying-Feng; Han, Chun-Mei; Shao, Yun; Tao, Yan-Duo

    2009-07-01

    Eight trace elements such as Ca, Cu, Fe, Mn, Zn, K, Mg and Na in twelve kinds of flower medicines were determined by flame-atomic absorption spectrometry with air-acetylene flame. The flower medicines include Pueraria lobata Ohwi., Gomphrena globosa L., Chrysanthemum morifolium Ramat., Prunus persica (L.) Batsch., Canna indica L., Pyrus bretschneideri Rehd P. spp, Rosa chinensis Jacq., Celosia cristata L., Sophora japonica L., Saussurea medusa Maxim. , Iris lactea var. chinensis (Fisch.) koidz. and Gentiana straminea Maxim.. All of the flowers were commonly used in Tibetan medicines. Three kinds of the flowers were bought in the market and the others were picked in Qinghai province. These flower medicines were selected, dried and powdered, 4.000 g was weighed accurately with analytical balance, and five portions were used for each kind of sample. The content of eight trace elements in these flower medicines was determined and the difference in the content was observed. The recovery rate obtained by the standard addition method was between 96.76% and 102.93%, and the RSD was between 1.13% and 3.46%, so the accuracy of the method was better and the precision of the method was good. The results of the experiment indicated that the contents of the eight trace elements were rich in the twelve kinds of flower medicines, and the content of three trace elements including K, Mg, Na were more than other trace elements in the twelve flower medicines. There were considerable differences in the content of the eight trace elements in different flower medicines and there were more trace elements in Saussure medusa Maxim., Iris lactea var. chinensis (Fisch.) koidz. Canna indica L. and Celosia cristata L. and less trace elements in Sophora japonica L. and Gentiana straminea Maxim.. The data of the experiment could provide an accurate and credible evidence for the reasonable medicinal use and deeper exploitation of these flower medicines. PMID:19798991

  13. Autonomic predictors of recovery following surgery: A comparative study

    PubMed Central

    Williamson, John B.; Lewis, Greg; Grippo, Angela J.; Lamb, Damon; Harden, Emily; Handleman, Mika; Lebow, Jocelyn; Carter, C. Sue; Porges, Stephen W.

    2015-01-01

    Although heart rate and temperature are continuously monitored in patients during recovery following surgery, measures that extract direct manifestations of neural regulation of autonomic circuits from the beat-to-beat heart rate may be more sensitive to outcome. We explore the relationship between features of autonomic regulation and survival in the prairie vole, a small mammal, with features of vagal regulation of the heart similar to humans. Cardiac vagal regulation is manifested in the beat-to-beat heart rate variability (HRV) pattern and can be quantified by extracting measures of the amplitude of periodic oscillations associated with spontaneous breathing. Thus, monitoring beat-to-beat heart rate patterns post-surgery in the prairie vole may provide an opportunity to dynamically assess autonomic adjustments during recovery. Surgeries to implant telemetry devices to monitor body temperature and continuous ECG in prairie voles are routinely performed in our laboratory. Ten of these implanted prairie voles died within 48 h post-surgery. To compare the post-surgery autonomic trajectories with typical surviving prairie voles, the post-surgery data from 17 surviving prairie voles were randomly selected. The data are reported hourly for 27 prairie voles between 6 and 14 h (1 h before the demise of the first subject) post-surgery. Receiver operator curves were calculated hourly for each variable to evaluate sensitivity in discriminating survival. The data illustrate that measures of HRV are the most sensitive indicators. These findings provide a foundation for investigating further neural mechanisms of cardiovascular function. PMID:20451468

  14. Comparative study of different isolates of murine sarcoma virus.

    PubMed Central

    Donoghue, D J; Sharp, P A; Weinberg, R A

    1979-01-01

    The RNA genomes of a variety of murine sarcoma viruses (MSV) were compared by heteroduplex analysis. These viruses included the Moloney-derived isolates 124-MSV, m1-MSV, m3-MSV, HT1-MSV, and NP-MSV and also two independent isolates, Gazdar MSV and 1712-MSV. All of these viral genomes exhibited the acquired cellular sequences previously identified in 3124-MSV and thought to be responsible for transformation and sarcomagenesis. The location of the acquired cellular sequences within the envelope gene was variable in different MSV isolates, suggesting that the cellular sequences can be expressed in different positions relative to murine leukemia virus-derived information present in MSV. Deletions in the gag coding region of the different MSVs were consistent with their known gag-related gene products. Based on several features of the hetero-duplex analysis and the known genealogical relationships of the different MSVs, various possible mechanisms for the formation of MSV are considered. Images PMID:229256

  15. Learning from imbalanced data: a comparative study for colon CAD

    NASA Astrophysics Data System (ADS)

    Yang, Xiaoyun; Zheng, Yalin; Siddique, Musib; Beddoe, Gareth

    2008-03-01

    Classification plays an important role in the reduction of false positives in many computer aided detection and diagnosis methods. The difficulty of classifying polyps lies in the variation of possible polyp shapes and sizes and the imbalance between the number of polyp and non-polyp regions available in the training data. CAD schemes for medical applications demand high levels of sensitivity even at the expense of keeping a certain number of false positives. In this paper, we investigate some state-of-the-art solutions to the imbalanced data problem: Synthetic Minority Over-sampling Technique (SMOTE) and weighted Support Vector Machines (SVM). We tested these methods using a diverse database of CT colonography, which included a wide spectrum of dificult cases to detect polyps. We performed several experiments with different combinations of over-sampling techniques on training data. The results demonstrated that SVMs have achieved much better performance over C4.5 with different over-sampling techniques. Also, the results show that weighted SVM without over-sampling can achieve comparable performance in terms of sensitivity and specificity to conventional SVM combined with the over-sampling approach.

  16. Muscle wasting in chronic alcoholics: comparative histochemical and biochemical studies.

    PubMed Central

    Langohr, H D; Wiethölter, H; Peiffer, J

    1983-01-01

    The comparative electrophysiologic, histochemical, and biochemical investigation of the anterior tibial muscle of 13 alcoholics indicates that neuropathy could be the cause of the chronic muscle weakness and wasting. Myopathic alterations did not predominate in the findings. It was concluded that the proximal muscle atrophy could also be attributed to neurogenic damage. Histochemical reactions in muscle specimens showed a selective type 2 atrophy and a slight increase of the mean diameter of type 1 fibres. Biochemical investigations revealed that the activities of a number of enzymes representative of energy supplying pathways--the glycogenolysis and glycolysis--as well as acid phosphatase activity in the muscle were lowered. A relationship could be assumed between the lowered glycolytic activity and the decline of the mean diameter of type 2 fibres. Oxidative enzymes were of similar activity in the alcoholics and the control group. The glycolytic enzyme activities were particularly important, being the most sensitive indicators of the onset, intensity, and course of neurogenic damage. These activities probably normalise during reinnervation of a muscle earlier than do the morphologic alterations; however, they were markedly lower in alcoholics with impaired liver function and cachexia, probably because of the catabolic metabolic conditions present in these cases. Images PMID:6221080

  17. Verruciform xanthoma: report of three patients with comparative dermoscopic study.

    PubMed

    Ohnishi, T; Shiraishi, H; Fukaya, S; Tanaka, T; Watanabe, S

    2015-03-01

    We report three cases of verruciform xanthoma (VX) in male patients aged 82, 88 and 39 years, respectively. The clinical appearance was of a mulberry-like area consisting of small papillae, which is typical of and specific to VX, and the diagnosis were histologically confirmed in all cases. Dermoscopy revealed that each surface papilla contained linear or hairpin vessels, which were surrounded by a marginal whitish rim. These structures are thought to correspond to dilated vessels in dermal papillae and papillated acanthotic epidermis, respectively. Furthermore, observation under compression (similar to diascopy) revealed yellow dots and debris, reflecting lipid-laden foam cells. In order to compare these findings with those of other disorders with similar findings, two patients with xanthogranuloma, six with sebaceous naevus, and three with senile sebaceous hyperplasia were examined. The dermoscopic findings in these patients were not similar to those of VX. Therefore, we believe that the above dermoscopic findings are specific to VX and could be helpful in diagnosis. PMID:25476138

  18. Comparative study of medium damped and detuned linear accelerator structures

    SciTech Connect

    Jean-Francois Ostiguy et al.

    2001-08-22

    Long range wakefields are a serious concern for a future linear collider based on room temperature accelerating structures. They can be suppressed either by detuning and or local damping or with some combination of both strategies. Detuning relies on precisely phasing the contributions of the dipole modes excited by the passage of a single bunch. This is accomplished by controlling individual mode frequencies, a process which dictates individual cell dimensional tolerances. Each mode must be excited with the correct strength; this in turn, determines cell-to-cell alignment tolerances. In contrast, in a locally damped structure, the modes are attenuated at the cell level. Clearly, mode frequencies and relative excitation become less critical in that context; mechanical fabrication tolerances can be relaxed. While local damping is ideal from the stand-point of long range wakefield suppression, this comes at the cost of reducing the shunt impedance and possibly unacceptable localized heating. Recently, the Medium Damped Structure (MDS), a compromise between detuning and local damping, has generated some interest. In this paper, we compare a hypothetical MDS to the NLC Rounded Damped Detuned Structure (RDDS) and investigate possible advantages from the standpoint fabrication tolerances and their relation to beam stability and emittance preservation.

  19. A comparative structural study of wet and dried ettringite

    SciTech Connect

    Renaudin, G.; Filinchuk, Y.; Neubauer, J.; Goetz-Neunhoeffer, F.

    2010-03-15

    Two different techniques were used to compare structural characteristics of 'wet' ettringite (stored in the synthesis mother liquid) and 'dried' ettringite (dried to 35% relative humidity over saturated CaCl{sub 2} solution). Lattice parameters and the water content in the channel region of the structure (site occupancy factor of the water molecule not bonded to cations) as well as microstructure parameters (size and strain) were determined from a Rietveld refinement on synchrotron powder diffraction data. Local environment of sulphate anions and of the hydrogen bonding network was characterized by Raman spectroscopy. Both techniques led to the same conclusion: the 'wet' ettringite sample immersed in the mother solution from the synthesis presents similar structural features as ettringite dried to 35% relative humidity. An increase of the a lattice parameter combined with a decrease of the c lattice parameter occurs on drying. The amount of structural water, the point symmetry of sulphate and the hydrogen bond network are unchanged when passing from the wet to the dried ettringite powder. Ettringite does not form a high-hydrate polymorph in equilibrium with alkaline solution, in contrast to the AFm phases that lose water molecules on drying. According to these results we conclude that ettringite precipitated in aqueous solution at the early hydration stages is of the same chemical composition as ettringite present in the hardening concrete.

  20. A comparative study of measurements from radiosondes, rocketsondes, and satellites

    NASA Technical Reports Server (NTRS)

    Nestler, M. S.

    1983-01-01

    Direct comparisons of operational products derived from measurements of radiance by satellites to measurements from conventional in situ sensors are important for the evaluation of satellite systems. However, errors in the in situ measurements themselves complicate such comparisons. Atmospheric temporal and spatial variability are also influential. These issues are investigated by means of a special field program composed of flights of dual radiosondes and multiple radiosondes launched near the time of NOAA-6 overpasses. Satellite derived mean layer temperatures, geopotential heights, and winds are compared with the same quantities determined from the in situ sensors. Of particular interest is the impact of in situ errors on these comparisons. It is shown that the radiosonde provides a precise pressure height relationship and therefore precise data for synoptic type use. Radar tracking of the radiosondes reveals, however, an imprecise pressure measurement which causes large differences between the actual altitude of the radiosonde and the altitude at which it is calculated to be. Radiosondes should be radar tracked and pressures calculated if the data are to be used for purposes other than synoptic use. Evaluation of rocketsonde data reveals a temperature precision of 1 to 2 K below about 55 km. Above 55 km, the precision decreases rapidly; rms differences of up to 11 K are obtained.

  1. A Comparative Study of Some Dynamic Stall Models

    NASA Technical Reports Server (NTRS)

    Reddy, T. S. R.; Kaza, K. R. V.

    1987-01-01

    Three semi-empirical aerodynamic stall models are compared with respect to their lift and moment hysteresis loop prediction, limit cycle behavior, easy implementation, and feasibility in developing the parameters required for stall flutter prediction of advanced turbines. For the comparison of aeroelastic response prediction including stall, a typical section model and a plate structural model are considered. The response analysis includes both plunging and pitching motions of the blades. In model A, a correction to the angle of attack is applied when the angle of attack exceeds the static stall angle. In model B, a synthesis procedure is used for angles of attack above static stall angles and the time history effects are accounted through the Wagner function. In both models the life and moment coefficients for angle of attack below stall are obtained from tabular data for a given Mach number and angle of attack. In model C, referred to an the ONERA model, the life and moment coefficients are given in the form of two differential equations, one for angles below stall, and the other for angles above stall. The parameters of those equations are nonlinear functions of the angle of attack.

  2. [Comparative study of 2 methods of measuring intestinal transit time].

    PubMed

    Vidal-Neira, L; León-Barúa, R

    1981-01-01

    In 20 healthy volunteers, intestinal transit times, obtained following a simple method, recently described, in which a small liquid-containing rubber bag is used as a marker, were compared with the times obtained following, simultaneously, another method, already universally accepted, in which small barium-impregnated pellets are used as markers. The intestinal transit determined with the rubber bag (TTI-B) (14.1 - 79.2 hours; mean +/- s.d.: 42.4 +/- 20.7 hours) were significantly shorter than the times determined with the plastic pellets (TTI) (26.4 - 88.1 hours; mean +/- s.d.: 60.2 +/- 25.5 hours (P less than 0.001). But, TTI-B and TTI correlate closely (r: + 0.86), and, furthermore, TTI-B results may be converted to TTI results with the help of a simple regression equation: TTI (in minutes) = 831 + 1.09 TTI-B (in minutes). After analyzing what has been observed in the present work and in previous works, it was concluded that the new method to measure intestinal transient time using the small rubber bag is reliable and simple, and that it may help to better understand what happens in some important gastrointestinal problems. PMID:7342626

  3. A Comparative Study Using CFD to Predict Iced Airfoil Aerodynamics

    NASA Technical Reports Server (NTRS)

    Chi, x.; Li, Y.; Chen, H.; Addy, H. E.; Choo, Y. K.; Shih, T. I-P.

    2005-01-01

    WIND, Fluent, and PowerFLOW were used to predict the lift, drag, and moment coefficients of a business-jet airfoil with a rime ice (rough and jagged, but no protruding horns) and with a glaze ice (rough and jagged end has two or more protruding horns) for angles of attack from zero to and after stall. The performance of the following turbulence models were examined by comparing predictions with available experimental data. Spalart-Allmaras (S-A), RNG k-epsilon, shear-stress transport, v(sup 2)-f, and a differential Reynolds stress model with and without non-equilibrium wall functions. For steady RANS simulations, WIND and FLUENT were found to give nearly identical results if the grid about the iced airfoil, the turbulence model, and the order of accuracy of the numerical schemes used are the same. The use of wall functions was found to be acceptable for the rime ice configuration and the flow conditions examined. For rime ice, the S-A model was found to predict accurately until near the stall angle. For glaze ice, the CFD predictions were much less satisfactory for all turbulence models and codes investigated because of the large separated region produced by the horns. For unsteady RANS, WIND and FLUENT did not provide better results. PowerFLOW, based on the Lattice Boltzmann method, gave excellent results for the lift coefficient at and near stall for the rime ice, where the flow is inherently unsteady.

  4. Surface Tension Studies of Alkyl Esters and Epoxidized Alkyl Esters Relevant to Oleochemically Based Fuel Additives

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We report the surface tension of several epoxidized oleochemicals and their comparable fatty esters at temperatures between 25 and 60 deg C. Surface tensions of the olefins measured at 40 deg C range from 25.9 mN m-1, for isobutyl oleate, to 28.4 mN m-1 for methyl linoleate. The epoxy versions of ...

  5. Governance Paradigms of Public Universities: An International Comparative Study

    ERIC Educational Resources Information Center

    Christopher, Joe

    2012-01-01

    This study aims to develop a conceptual model of the wider influencing forces impacting the governance paradigms of public universities. It draws on the multi-theoretical governance concept and seeks to identify these forces through the lens of chief audit executives using a qualitative research approach. The interview data supported by published…

  6. Workplace Discrimination and Americans with Psychiatric Disabilities: A Comparative Study

    ERIC Educational Resources Information Center

    An, Sunghee; Roessler, Richard T.; McMahon, Brian T.

    2011-01-01

    This study reports findings from an analysis of employment allegations and resolutions maintained in the U.S. Equal Employment Opportunity Commission (EEOC) database. Spanning the years 1992 to 2005, the data were aggregated for individuals with psychiatric disabilities and individuals with a variety of physical, sensory, and neurological…

  7. Factors Influencing International Students' Career Choice: A Comparative Study

    ERIC Educational Resources Information Center

    Singaravelu, Hemla D.; White, Lyle J.; Bringaze, Tammy B.

    2005-01-01

    This study examines the career development behavior of Asian international, non-Asian international, and domestic students, specifically the certainty of career and major choice and environmental factors that have influenced their choices. Environmental factors include family, school counselors, teacher, friends, and government. The results show…

  8. Pre- and Post KERA Students' Writing Skills: A Comparative Study.

    ERIC Educational Resources Information Center

    Sultana, Qaisar; Kay, Lisa

    This study was conducted to determine whether the writing skills, as measured by the University Writing Requirement (UWR), of Kentucky high school graduates who had participated in Kentucky's Commonwealth Accountability Testing System (CATS) writing portfolios had improved in comparison with their peers in the past who had not done the writing…

  9. Comparative study of phytosterol derivatives in monovarietal olive oils.

    PubMed

    Gómez-Coca, Raquel B; Fernandes, Gabriel D; Del Aguila-Sánchez, Chellah; Pérez-Camino, María Del Carmen; Moreda, Wenceslao

    2014-06-18

    Plant sterols and their derivatives are minor compounds that have been extensively studied in vegetable oils, mainly in olive oil, where they are closely related with its identity. The objective of this work is to determine the content of free and esterified steryl glucosides and their profiles in olive oil in relation to different geographical situation of olive orchards, cultivar, farming modality, and sampling time. The orchards under study were located in the outer ring of the submetropolitan area of Madrid (Spain), where olives from Cornicabra, Manzanilla Cacereña, Manzanilla Castellana, and Picual varieties were grown under traditional and organic modes, and harvested in four different samplings. Conclusions state that cultivar, farming mode, and light exposure do not have outstanding effects, whereas pedoclimate might affect the steryl glucoside presence in a substantial way. Further studies are being carried out presently in order to confirm such statement. Also glucoside derivative profiles are discussed, and reasons for differences with results in previous studies pointed out. PMID:24861171

  10. Education in Germany since Unification. Oxford Studies in Comparative Education.

    ERIC Educational Resources Information Center

    Phillips, David, Ed.

    This collection of papers discusses issues related to education in Germany since its unification. The papers include: "The Legacy of Unification" (David Phillips); "Change and Continuity in Education After the 'Wende'" (E. J. Neather); "A Study of Teachers' Perceptions in Brandenburg 'Gesamtschulen'" (Stephanie Wilde); "Memory and Judgement: How…

  11. Englishes in the Outer and Expanding Circles: A Comparative Study

    ERIC Educational Resources Information Center

    Davydova, Julia

    2012-01-01

    The major objective of the study is to develop a framework allowing for the systematic investigation of the institutionalised varieties and performance varieties of English (also known as learner Englishes). This involves a detailed description of the forms of English spoken in India and in Russia as well as discussion of sociolinguistic histories…

  12. Principal Leadership and Mathematics Achievement: An International Comparative Study

    ERIC Educational Resources Information Center

    Shin, Seon-Hi; Slater, Charles L.

    2010-01-01

    This study investigated the differences and similarities in the impact of school leadership on student mathematics achievement in different global regions using TIMSS international data. Three-level unconditional and conditional hierarchical models were fitted to the data in each country. The findings showed that the variables of teacher…

  13. Entering Student Affairs: A Comparative Study of Graduate School Choice

    ERIC Educational Resources Information Center

    Mertz, Norma; Eckman, Ellen; Strayhorn, Terrell

    2012-01-01

    This article describes the college choice process of graduate students in College Student Personnel programs at a public university and a private religiously affiliated university. Despite differences in size, mission, and location of the two institutions studied, the research findings show that respondent populations were similar demographically…

  14. Adolescent Literacy and School Structure: A Comparative Case Study

    ERIC Educational Resources Information Center

    Codispoti, Marie

    2010-01-01

    Students who leave elementary school after fourth grade may not be receiving adequate literacy instruction. Although many recent studies have focused on a drop in test scores for middle school students, a gap exists in the literature with regard to explicit literacy instruction in elementary and non-elementary school settings. To inform educators…

  15. Comparative study of switchgrass cultivars using RNA sequencing technology

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Switchgrass (Panicum virgatum L.) is a C4 perennial grass, identified as a promising bioenergy crop. Switchgrass exists in two ecotypes, upland and lowland, which are heterotic, or genetically complementary to each other. The objectives of this study are to assess the potential of SNP markers as a b...

  16. Effective Teacher Characteristics: A Two Nation Causal Comparative Study

    ERIC Educational Resources Information Center

    Elliott, Bianca Lynn Shindley

    2010-01-01

    School administrators who recruit teachers domestically and abroad lack an internationally accepted checklist for effective teachers with which to evaluate teacher applicants. This study was conducted to use the elements of a U.S.-based effective teacher checklist survey with a sample of secondary teachers in Guatemala and Japan to describe the…

  17. A Comparative Study of Small Group Fluency Instruction

    ERIC Educational Resources Information Center

    Kuhn, Melanie

    2005-01-01

    The present study investigated the reading development of small groups of learners making the transition from intentional decoding to fluent reading. The research focused on the relative effectiveness of repeated and wide reading as a means of developing reading fluency. It also looked at the importance of expressive, or prosodic, reading in…

  18. A Comparative Study of Three Revision Methods in EFL Writing

    ERIC Educational Resources Information Center

    Srichanyachon, Napaporn

    2011-01-01

    In an attempt to explore effective instruction in the English as a Foreign Language (EFL) setting, this study investigated language errors identified by students and teachers in three different revision stages: self-revision, peer revision, and teacher revision. It gave the focus to the effects of the three different methods on learners' writing…

  19. Automated Versus Conventional Systematic Desensitization: A Study of Comparative Effectiveness.

    ERIC Educational Resources Information Center

    De Csipkes, Robert A.; Rowe, Wayne

    This study investigates whether variations in method of presentation of anxiety items (experimenter's voice, experimenter's taped voice, subject's taped voice) will result in differences in autonomic arousal (as measured by self-report, galvanic skin response, cardiac rate, blood pressure). Ss were 24 Naval Academy midshipmen. The procedure…

  20. Library Abuse in Academic Institutions: A Comparative Study.

    ERIC Educational Resources Information Center

    Obiagwu, Marcel C.

    1992-01-01

    Describes a study that investigated the abuse of library materials through theft, mutilation, unauthorized borrowing, and vandalism at the University of Port Harcourt (Nigeria) and King Fahd University of Petroleum and Minerals (Saudi Arabia). Motivations for abuse are discussed, and recommendations for improved collection protection are…