Multi-Body Dynamic Contact Analysis. Tool for Transmission Design SBIR Phase II Final Report
2003-04-01
shapes and natural frequencies were computed in COSMIC NASTRAN, and were validated against the published experimental modal analysis [17]. • Using...COSMIC NASTRAN via modal superposition. • Results from the structural analysis (mode shapes or forced response) were converted into IDEAS universal...ARMY RESEARCH LABORATORY Multi-body Dynamic Contact Analysis Tool for Transmission Design SBIR Phase II Final Report by
Multi-body Dynamic Contact Analysis Tool for Transmission Design
2003-04-01
frequencies were computed in COSMIC NASTRAN, and were validated against the published experimental modal analysis [17]. • Using assumed time domain... modal superposition. • Results from the structural analysis (mode shapes or forced response) were converted into IDEAS universal format (dataset 55...ARMY RESEARCH LABORATORY Multi-body Dynamic Contact Analysis Tool for Transmission Design SBIR Phase II Final Report by
NASA Astrophysics Data System (ADS)
Al-Wahaibi, Lamya H.; Sujay, Subramaniam; Muthu, Gangadharan Ganesh; El-Emam, Ali A.; Venkataramanan, Natarajan S.; Al-Omary, Fatmah A. M.; Ghabbour, Hazem A.; Percino, Judith; Thamotharan, Subbiah
2018-05-01
A detailed structural analysis of two adamantane derivatives namely, ethyl 2-[(Z)-1-(adamantan-1-yl)-3-(phenyl)isothioureido]acetate I and ethyl 2-[(Z)-1-(adamantan-1-yl)-3-(4-fluorophenyl)isothioureido]acetate II is carried out to understand the effect of fluorine substitution. The introduction of fluorine atom alters the crystal packing and is completely different from its parent compound. The fluorine substitution drastically reduced the intermolecular H⋯H contacts and this reduction is compensated by intermolecular F⋯H and F⋯F contacts. The relative contributions of various intermolecular contacts present in these structures were quantified using Hirshfeld surface analysis. Energetically significant molecular pairs were identified from the crystal structures of these compounds using PIXEL method. The structures of I and II are optimized in gas and solvent phases using the B3LYP-D3/6-311++G(d,p) level of theory. The quantum theory of atoms-in-molecules (QTAIM) analysis was carried out to estimate the strengths of various intermolecular contacts present in these molecular dimers. The results suggest that the Hsbnd H bonding take part in the stabilization of crystal structures. The experimental and theoretical UV-Vis results show the variations in HOMO and LUMO energy levels. In silico docking analysis indicates that both compounds I and II may exhibit inhibitory activity against 11-β-hydroxysteroid dehydrogenase 1 (11-β-HSD1).
Tibiofemoral contact stress and stress distribution evaluation of total knee arthroplasties.
Szivek, J A; Cutignola, L; Volz, R G
1995-08-01
The Fuji film (Itochu, Los Angeles, CA) area analysis technique demonstrates that a more accurate assessment of tibiofemoral contact stresses is possible when the film is used at 37 degrees C and at the upper end of its sensitivity range (in this case, a 2,000-N load). An AMK with a regular and Hylamer-M insert (DePuy, Warsaw, IN), an MG II (Zimmer, Warsaw, IN), an Omnifit (Osteonics, Allendale, NJ), an Ortholoc III (Dow Corning Wright, Midland, MI), a PCA II (Howmedica, Rutherford, NJ), and a PFC (Johnson & Johnson Orthopaedics, Raynham, MA) had average contact stresses that varied only 12% at 60 degrees flexion. At 0 degrees, 15 degrees and 60 degrees flexion, stresses ranged from 13 to 25 MPa. Contact area distribution ratios, which were smaller at 37 degrees C than at 24 degrees C, provide a quantitative means of grouping implants according to the shape of the tibiofemoral contact area. The Omnifit, MG II, PCA II, and PFC had small ratios (symmetric areas). The AMK and Ortholoc III had large ratios (asymmetric contact areas). If the impression is reflective of wear, it would be expected to be focal in knees with small ratios and contact areas, and uniform in knees with large ratios and contact areas, whereas large ratios and small areas would imply a linear wear pattern. Calibrated electrical resistance contact stress measurements indicated that the Fuji film measurements underestimated the magnitude of contact stresses. They also provided a means of quantifying the rate of area increase during initial loading of the knees, with the highest area increase noted for the knee with the roughest insert (Ortholoc III) and the lowest area increase for the knee with the smoothest insert (PCA II).
Subthalamus stimulation in Parkinson disease: Accounting for the bilaterality of contacts.
Lemaire, Jean-Jacques; Pereira, Bruno; Derost, Philippe; Vassal, François; Ulla, Miguel; Morand, Dominique; Coll, Guillaume; Gabrillargues, Jean; Marques, Ana; Debilly, Bérangère; Coste, Jérôme; Durif, Franck
2016-01-01
Deep brain stimulation (DBS) in Parkinson's disease uses bi-hemispheric high-frequency stimulation within the subthalamus, however, the specific impacts of bilaterality of DBS are still not clear. Thus, we aimed to study the individual-level clinical impact of locations of right-left contact pair-up accounting for each subthalamic nucleus (STN) anatomy. Contact locations and effects at 1 year were studied retrospectively in an unselected series of 53 patients operated between 2004 and 2010. Location of contacts was defined relatively to the main axis of STN used to map longitudinal and transversal positions, and STN membership (out meaning out-of-STN). Contact pairings were described via three methods: (i) Unified contact location (UCL) collapsing DBS into an all-in-one contact; (ii) balance of contact pair-up (BCPU), defined as symmetric or asymmetric regardless of laterality; (iii) hemisphere-wise most frequent contact pair-up (MFCP) regardless of BCPU. Clinical data were: mean levodopa equivalent dose, Unified Parkinson's Disease Rating Scale (UPDRS) motor score III without medication, UPDRS II and III speech sub-scores, UPDRS II freezing sub-score, 1 year versus preoperative values, with and without levodopa. Ad-hoc two-sided tests were used for statistical analysis. Worsening speech, was more frequent for UCL_out patients and when the left MFCP contact was rear and/or superolateral, however, it less frequent for BCPU-asymmetric patients. Worsening freezing was more frequent when the right MFCP contact was rear and superolateral. These results point to strategies for minimizing dysarthria and freezing as adverse effects of DBS.
Subthalamus stimulation in Parkinson disease: Accounting for the bilaterality of contacts
Lemaire, Jean-Jacques; Pereira, Bruno; Derost, Philippe; Vassal, François; Ulla, Miguel; Morand, Dominique; Coll, Guillaume; Gabrillargues, Jean; Marques, Ana; Debilly, Bérangère; Coste, Jérôme; Durif, Franck
2016-01-01
Background: Deep brain stimulation (DBS) in Parkinson's disease uses bi-hemispheric high-frequency stimulation within the subthalamus, however, the specific impacts of bilaterality of DBS are still not clear. Thus, we aimed to study the individual-level clinical impact of locations of right-left contact pair-up accounting for each subthalamic nucleus (STN) anatomy. Methods: Contact locations and effects at 1 year were studied retrospectively in an unselected series of 53 patients operated between 2004 and 2010. Location of contacts was defined relatively to the main axis of STN used to map longitudinal and transversal positions, and STN membership (out meaning out-of-STN). Contact pairings were described via three methods: (i) Unified contact location (UCL) collapsing DBS into an all-in-one contact; (ii) balance of contact pair-up (BCPU), defined as symmetric or asymmetric regardless of laterality; (iii) hemisphere-wise most frequent contact pair-up (MFCP) regardless of BCPU. Clinical data were: mean levodopa equivalent dose, Unified Parkinson's Disease Rating Scale (UPDRS) motor score III without medication, UPDRS II and III speech sub-scores, UPDRS II freezing sub-score, 1 year versus preoperative values, with and without levodopa. Ad-hoc two-sided tests were used for statistical analysis. Results: Worsening speech, was more frequent for UCL_out patients and when the left MFCP contact was rear and/or superolateral, however, it less frequent for BCPU-asymmetric patients. Worsening freezing was more frequent when the right MFCP contact was rear and superolateral. Conclusions: These results point to strategies for minimizing dysarthria and freezing as adverse effects of DBS. PMID:27990316
Nickel adsorption onto polyurethane ethylene and vinyl acetate sorbents.
Iqbal, Munawar; Ali, Zahid; Qamar, M Afzal; Ali, Abid; Hussain, Fida; Abbas, Mazhar; Nisar, Jan
2017-07-01
The present study was conducted to appraise the efficiencies of polyurethane ethylene sorbent (PES) and vinyl acetate sorbent (VAS) for nickel (Ni) adsorption. Process variables, i.e. Ni(II) ions initial concentration, pH, contact time and adsorbent dosage were optimized by response surface methodology (RSM) approach. The Ni(II) adsorption was fitted to the kinetic models (pseudo-first-order and pseudo-second-order) and adsorption isotherms (Freundlich and Langmuir). At optimum conditions of process variables, 171.99 mg/g (64.7%) and 388.08 mg/g (92.7%) Ni(II) was adsorbed onto PES and VAS, respectively. The RSM analysis revealed that maximum Ni(II) adsorption can be achieved at 299 mg/L Ni(II) ions initial concentration, 4.5 pH, 934 min contact time and 1.3 g adsorbent dosage levels for PES, whereas the optimum values for VAS were found to be 402 mg/L Ni(II) ions initial concentration, 4.6 pH, 881 min contact time and 1.2 g adsorbent dosage, respectively. The -OH and -C = O- were involved in the Ni(II) adsorption onto PES and VAS adsorbents. At optimum levels, up to 53.67% and 80.0% Ni(II) was removed from chemical industry wastewater using PES and VAS, respectively, which suggest that PES and VAS could possibly be used for Ni(II) adsorption from industrial wastewater.
Keith, D; Hong, B; Christensen, M
1997-05-01
A quick, simple, and efficient extraction technique was developed for the removal of protein from soft hydrophilic contact lenses. An extraction solvent consisting of a 50:50 mix of 0.2% trifluoroacetic acid and acetonitrile was used to remove protein from in vitro laboratory-deposited and human-worn contact lenses. The protein removed was analyzed using HPLC, bicinchoninic acid (BCA) analysis, and SDS-PAGE gel electreophoresis. Extraction efficiency for lysozyme from laboratory-deposited Group IV lenses was determined to be approximately 100%. Group IV human-worn contact lenses were extracted and analyzed for lysozyme by HPLC and total protein by bicinchoninic acid (BCA) analysis. Groups I, II, III, and IV contact lenses deposited with an artificial tear protein solution and human-worn lenses were extracted and analyzed by SDS-PAGE gel electreophoresis and micro-BCA. The ACN/TFA procedure offers a simple, quick, and efficient extraction technique for removal of protein from contact lenses for subsequent analysis.
Analysis of the evolved contact system V367 Cygni
NASA Astrophysics Data System (ADS)
Li, Yan-Feng; Leung, Kam-Ching
1987-02-01
Three groups of observations of V367 Cyg - Fresa's blue light curve (1957-1960, group I), Heiser's UBV light curves (1960-1961, group II), and BV light curves of Kalv and Pustylnik (1967-1973, group III) - were analyzed separately with the Wilson and Devinney approach. An appropriate value of the mass ratio of the system was derived from a q-search procedure. Three contact solutions were obtained with over-contact of 0.0 percent (critical contact), 4.5 percent, and 8.8 percent, corresponding to the observations of group I, group II, and group III respectively; and no third lights were found in the light curves. Absolute dimensions of the system were calculated with the photometric mass ratio. The observed radii are found to be about a factor of six greater than the zero-age main-sequence values for stars of corresponding masses. It is suggested that V367 Cyg is at an evolved contact phase with active mass transfer or mass loss or both.
Contact Resistance Evolution and Degradation of Highly Cycled Micro-Contacts
2014-03-27
i List of Acronyms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ii I. Introduction...scanning electron microscope EDS energy dispersive X-ray spectroscopy ii CONTACT RESISTANCE EVOLUTION AND DEGRADATION OF HIGHLY CYCLED MICRO-CONTACTS I
NASA Technical Reports Server (NTRS)
Litvin, F. L.; Handschuh, R. F.; Zhang, J.
1988-01-01
A method for generation of crowned pinion tooth surfaces using a surface of revolution is developed. The crowned pinion meshes with a regular involute gear and has a prescribed parabolic type of transmission errors when the gears operate in the aligned mode. When the gears are misaligned the transmission error remains parabolic with the maximum level still remaining very small (less than 0.34 arc second for the numerical examples). Tooth Contact Analysis (TCA) is used to simulate the conditions of meshing, determine the transmission error, and the bearing contact.
Adsorption of mercury from aqueous solutions using palm oil fuel ash as an adsorbent - batch studies
NASA Astrophysics Data System (ADS)
Imla Syafiqah, M. S.; Yussof, H. W.
2018-03-01
Palm oil fuel ash (POFA) is one of the most abundantly produced waste materials. POFA is widely used by the oil palm industry which was collected as ash from the burning of empty fruit bunches fiber (EFB) and palm oil kernel shells (POKS) in the boiler as fuel to generate electricity. Mercury adsorption was conducted in a batch process to study the effects of contact time, initial Hg(II) ion concentration, and temperature. In this study, POFA was prepared and used for the removal of mercury(II) ion from the aqueous phase. The effects of various parameters such as contact time (0- 360 min), temperature (15 – 45 °C) and initial Hg(II) ion concentration (1 – 5 mg/L) for the removal of Hg(II) ion were studied in a batch process. The surface characterization was examined by scanning electron microscopy (SEM) and particle size distribution analysis. From this study, it was found that the highest Hg(II) ion removal was 99.60 % at pH 7, contact time of 4 h, initial Hg(II) ion concentration of 1 mg/L, adsorbent dosage 0.25 g and agitation speed of 100 rpm. The results implied that POFA has the potential as a low-cost and environmental friendly adsorbent for the removal of mercury from aqueous solution.
[Sport injuries in full contact and semi-contact karate].
Greier, K; Riechelmann, H; Ziemska, J
2014-03-01
Karate enjoys great popularity both in professional and recreational sports and can be classified into full, half and low contact styles. The aim of this study was the analysis of sports injuries in Kyokushinkai (full contact) and traditional Karate (semi-contact). In a retrospective study design, 215 active amateur karateka (114 full contact, 101 semi-contact) were interviewed by means of a standardised questionnaire regarding typical sport injuries during the last 36 months. Injuries were categorised into severity grade I (not requiring medical treatment), grade II (single medical treatment), grade III (several outpatient medical treatments) and grade IV (requiring hospitalisation). In total, 217 injuries were reported in detail. 125 injuries (58%) occurred in full contact and 92 (42%) in semi-contact karate. The time related injury rate of full contact karateka was 1.9/1000 h compared to 1.3/1000 h of semi-contact karateka (p < 0.05). The most common types of injuries were musculoskeletal contusions (33% full contact, 20% semi-contact), followed by articular sprains with 19% and 16%. The lower extremity was affected twice as often in full contact (40%) as in semi-contact (20%) karate. Training injuries were reported by 80% of the full contact and 77% of the semi-contact karateka. Most injuries, both in training and competition, occurred in kumite. 75% of the reported injuries of full contact and 70% of semi-contact karateka were classified as low grade (I or II). The high rate of injuries during training and kumite (sparring) points to specific prevention goals. The emphasis should be put on proprioceptive training and consistent warm-up. In the actual competition the referees play a vital role regarding prevention. © Georg Thieme Verlag KG Stuttgart · New York.
Patch testing with fragrance mix II: results of the IVDK 2005-2008.
Krautheim, Andrea; Uter, Wolfgang; Frosch, Peter; Schnuch, Axel; Geier, Johannes
2010-11-01
The fragrance mix (FM I), established in 1977, detects the majority, but not all cases of contact allergy to fragrances. Based on European research 2002/2003, fragrance mix II (FM II) was developed to supplement FM I. In 2005, the German Contact Dermatitis Research Group (DKG) added FM II to their baseline series. To evaluate reactions to FM II and its constituents in routine patch testing. Retrospective data analysis of the Information Network of Departments of Dermatology (IVDK), 2005-2008, of patch test results with FM II and its constituents. A total of 35 633 patients were patch tested with FM II as part of the DKG baseline series. Of these, 1742 (4.9%) reacted positively. Concomitant reactions to FM I were observed in 41.9% of the patients reacting to FM II. In 367 FM II-positive patients, a full breakdown test of the mix was performed. Of these, 47.7% reacted to hydroxyisohexyl 3-cyclohexene carboxaldehyde, 16.1% to citral, 11.4% to farnesol, 3.8% to hexyl cinnamal, 2.7% to coumarin, and 2.5% to citronellol. FM II is an important screening and diagnostic tool to detect fragrance allergy. Hydroxyisohexyl 3-cyclohexene carboxaldehyde is the most important fragrance allergen in FM II. © 2010 John Wiley & Sons A/S.
Contact Resistance Evolution and Degradation of Highly Cycled
2014-03-27
i List of Acronyms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ii I. Introduction...scanning electron microscope EDS energy dispersive X-ray spectroscopy ii CONTACT RESISTANCE EVOLUTION AND DEGRADATION OF HIGHLY CYCLED MICRO-CONTACTS I
Composition, apparatus, and process, for sorption of gaseous compounds of group II-VII elements
Tom, Glenn M.; McManus, James V.; Luxon, Bruce A.
1991-08-06
Scavenger compositions are disclosed, which have utility for effecting the sorptive removal of hazardous gases containing Group II-VII elements of the Periodic Table, such as are widely encountered in the manufacture of semiconducting materials and semiconductor devices. Gas sorption processes including the contacting of Group II-VII gaseous compounds with such scavenger compositions are likewise disclosed, together with critical space velocity contacting conditions pertaining thereto. Further described are gas contacting apparatus, including mesh structures which may be deployed in gas contacting vessels containing such scavenger compositions, to prevent solids from being introduced to or discharged from the contacting vessel in the gas stream undergoing treatment. A reticulate heat transfer structure also is disclosed, for dampening localized exothermic reaction fronts when gas mixtures comprising Group II-VII constituents are contacted with the scavenger compositions in bulk sorption contacting vessels according to the invention.
On contact modelling in isogeometric analysis
NASA Astrophysics Data System (ADS)
Cardoso, R. P. R.; Adetoro, O. B.
2017-11-01
IsoGeometric Analysis (IGA) has proved to be a reliable numerical tool for the simulation of structural behaviour and fluid mechanics. The main reasons for this popularity are essentially due to: (i) the possibility of using higher order polynomials for the basis functions; (ii) the high convergence rates possible to achieve; (iii) the possibility to operate directly on CAD geometry without the need to resort to a mesh of elements. The major drawback of IGA is the non-interpolatory characteristic of the basis functions, which adds a difficulty in handling essential boundary conditions and makes it particularly challenging for contact analysis. In this work, the IGA is expanded to include frictionless contact procedures for sheet metal forming analyses. Non-Uniform Rational B-Splines (NURBS) are going to be used for the modelling of rigid tools as well as for the modelling of the deformable blank sheet. The contact methods developed are based on a two-step contact search scheme, where during the first step a global search algorithm is used for the allocation of contact knots into potential contact faces and a second (local) contact search scheme where point inversion techniques are used for the calculation of the contact penetration gap. For completeness, elastoplastic procedures are also included for a proper description of the entire IGA of sheet metal forming processes.
Special tinted contact lens on colour-defects.
Mutilab, H A; Sharanjeet-Kaur; Keu, L K; Choo, P F
2012-01-01
The objective of this study was to determine the visual function of colour-deficient subjects when wearing special red tint contact lenses. A total of 17 subjects with congenital colour vision deficiency (14 deutans and 3 protans), voluntarily participated in this study. The average age for the subjects was 23.00 ± 4.06 years old. Visual functions tested were visual acuity (LogMAR), contrast sensitivity (FACT Chart) and stereopsis (TNO and Howard Dolman tests). Two types of special red tint lenses were used in this study; Type I (light red) and Type II (dark red). The protans and deutans showed no significant changes in visual acuity and contrast sensitivity when wearing either type of contact lens. Stereopsis testing using the Horward-Dolman test gave no significant changes but significant differences were seen using the TNO test. Stereopsis using the TNO test was significantly poorer with the red tinted contact lenses compared to without for both protons and deutans. Testing binocularly with Ishihara plates showed that 88% (n=15) of patients passed the test with Type I and Type II contact lenses. When D15 test was done, 3 patients (17.6%) were 'normal' when using the Type I contact lenses and 2 patients (11.8%) were 'normal' when using the Type II contact lenses. However, with FM100Hue test, most patients showed deutan responses. Total error scores (TES) were found to be higher with Type I and Type II contact lenses compared to without. The Type I and II special tinted contact lens used in this study did not cause a reduction of visual acuity and contrast sensitivity for the colour defects. Stereopsis was also not reduced with the Type I and Type II contact lenses for the colour defects except when tested with the TNO test. Colour vision defects became difficult to detect using the Ishihara plates but FM100Hue test did not show any improvement with the Type I and Type II contact lenses.
Fu, Yong; Huang, Yue; Hu, Jianshe; Zhang, Zhengjie
2018-03-01
A green functional adsorbent (CAD) was prepared by Schiff base reaction of chitosan and amino-modified diatomite. The morphology, structure and adsorption properties of the CAD were characterized by Fourier transform infrared spectroscopy, thermogravimetric analysis, scanning electron microscopy and Brunauer Emmett Teller measurements. The effect of pH value, contact time and temperature on the adsorption of Hg(II) ions for the CAD is discussed in detail. The experimental results showed that the CAD had a large specific surface area and multifunctional groups such as amino, hydroxyl and Schiff base. The optimum adsorption effect was obtained when the pH value, temperature and contact time were 4, 25 °C and 120 min, respectively, and the corresponding maximum adsorption capacity of Hg(II) ions reached 102 mg/g. Moreover, the adsorption behavior of Hg(II) ions for the CAD followed the pseudo-second-order kinetic model and Langmuir model. The negative ΔG 0 and ΔH 0 suggested that the adsorption was a spontaneous exothermic process.
NASA Astrophysics Data System (ADS)
Zhu, X.; Xu, W.
2017-11-01
This study presents an investigation on the behavior of adhesive contact between a rigid sphere and an elastic film which is either perfectly bonded (case I) or in frictionless contact (case II) with a rigid substrate. By using linear fracture mechanics, we formulate an convenient semi-analytical approach to develop relations between the applied force, penetration depth and contact radius. Finite element analysis (FEA) is used to verify the relationships. Our results reveal that the interfacial boundary conditions between the film and substrate have distinct effects on the adhesive contact behavior between the sphere and the film. The aim of the present study is to provide an instructive inspiration for controlling adhesion strength of the thin film subject to adhesive contact.
2000-12-01
Numerical Simulations ..... ................. .... 42 1.4.1. Impact of a rod on a rigid wall ..... ................. .... 42 1.4.2. Impact of two...dissipative properties of the proposed scheme . . . . 81 II.4. Representative Numerical Simulations ...... ................. ... 84 11.4.1. Forging of...Representative numerical simulations ...... ............. .. 123 111.3. Model Problem II: a Simplified Model of Thin Beams ... ......... ... 127 III
Uter, W; Amario-Hita, J C; Balato, A; Ballmer-Weber, B; Bauer, A; Belloni Fortina, A; Bircher, A; Chowdhury, M M U; Cooper, S M; Czarnecka-Operacz, M; Dugonik, A; Gallo, R; Giménez-Arnau, A; Johansen, J D; John, S M; Kieć-Świerczyńska, M; Kmecl, T; Kręcisz, B; Larese Filon, F; Mahler, V; Pesonen, M; Rustemeyer, T; Sadowska-Przytocka, A; Sánchez-Pérez, J; Schliemann, S; Schuttelaar, M L; Simon, D; Spiewak, R; Valiukevičienė, S; Weisshaar, E; White, I R; Wilkinson, S M
2017-09-01
Contact allergy is a common condition and can severely interfere with daily life or professional activities. Due to changes in exposures, such as introduction of new substances, new products or formulations and regulatory intervention, the spectrum of contact sensitization changes. To evaluate the current spectrum of contact allergy to allergens present in the European baseline series (EBS) across Europe. Retrospective analysis of data collected by the European Surveillance System on Contact Allergies (ESSCA, www.essca-dc.org) in consecutively patch-tested patients, 2013/14, in 46 departments in 12 European countries. Altogether, 31 689 patients were included in the analysis. Compared to a similar analysis in 2004, the prevalence of contact allergy to methylisothiazolinone went up to around 20% in several departments. In comparison, contact allergy to the metals nickel, cobalt and chromium remained largely stable, at 18.1%, 5.9% and 3.2%, respectively, similar to mostly unchanged prevalence with fragrance mix I, II and Myroxylon pereirae (balsam of Peru) at 7.3%, 3.8% and 5.3%, respectively. In the subgroup of departments diagnosing (mainly) patients with occupational contact dermatitis, the prevalence of work-related contact allergies such as epoxy resin or rubber additives was found to be increased, compared to general dermatology departments. Continuous surveillance of contact allergy based on network data offers the identification of time trends or persisting problems, and thus enables focussing in-depth research (subgroup analyses, exposure analysis) on areas where it is needed. © 2017 European Academy of Dermatology and Venereology.
Mohsin, Abdul Habeeb Bin; Reddy, Varalakshmi; Kumar, Praveen; Raj, Jeevan; Babu, Siva Santosh
2017-01-01
Introduction The aim of this study was to evaluate & compare the wetting ability of five saliva substitutes & distilled water on heat-polymerized acrylic resin. Contact angle of the saliva substitute on denture base can be taken as an indicator of wettability. Good wetting of heat-polymerized acrylic resin is critical for optimum retention of complete dentures. Methods Two hundred & forty samples of heat-polymerized acrylic resin were fabricated using conventional method. 240 samples divided into 6 groups with 40 samples in each group. Advancing & Receding contact angles were measured using Contact Angle Goniometer & DSA4 software analysis. Results Anova test was carried out to test the significance in difference of contact angle values in the six groups. The mean of advancing angle values & mean of receding angle values of all the six groups has shown statistically significant difference between the groups. The mean of angle of hysteresis values of all the six groups are statistically not significant between the groups. A multiple comparison using Bonferroni’s test was carried out to verify the significance of difference between the contact angles in a pair of groups. Statistically significant difference was seen when Aqwet (Group II) was compared to Distilled water (Group I), Wet Mouth (Group III), E-Saliva (Group IV), Biotene (Group V), and Moi-Stir (Group VI). Conclusion The contact angles of five saliva substitutes and distilled water were measured and compared. Group II (AQWET) has the lowest advancing and receding contact angle values and the highest angle of hysteresis on heat-polymerized acrylic resin. Based on contact angle values, Group II (AQWET) has the best wetting ability on heat-cured acrylic resins. The ability of saliva to wet the denture surface is one of the most important properties for complete denture retention in dry mouth cases. PMID:29187918
Phuthong, Witchukorn; Huang, Zubin; Wittkopp, Tyler M.; ...
2015-07-28
To investigate the dynamics of photosynthetic pigment-protein complexes in vascular plants at high resolution in an aqueous environment, membrane-protruding oxygen-evolving complexes (OECs) associated with photosystem II (PSII) on spinach ( Spinacia oleracea) grana membranes were examined using contact mode atomic force microscopy. This study represents, to our knowledge, the first use of atomic force microscopy to distinguish the putative large extrinsic loop of Photosystem II CP47 reaction center protein (CP47) from the putative oxygen-evolving enhancer proteins 1, 2, and 3 (PsbO, PsbP, and PsbQ) and large extrinsic loop of Photosystem II CP43 reaction center protein (CP43) in the PSII-OEC extrinsicmore » domains of grana membranes under conditions resulting in the disordered arrangement of PSII-OEC particles. Moreover, we observed uncharacterized membrane particles that, based on their physical characteristics and electrophoretic analysis of the polypeptides associated with the grana samples, are hypothesized to be a domain of photosystem I that protrudes from the stromal face of single thylakoid bilayers. Furthermore, our results are interpreted in the context of the results of others that were obtained using cryo-electron microscopy (and single particle analysis), negative staining and freeze-fracture electron microscopy, as well as previous atomic force microscopy studies.« less
Pujol, Rémy; Pickett, Sarah B.; Nguyen, Tot Bui; Stone, Jennifer S.
2014-01-01
Sensory receptors in the vestibular system (hair cells) encode head movements and drive central motor reflexes that control gaze, body movements, and body orientation. In mammals, type I and II vestibular hair cells are defined by their shape, contacts with vestibular afferent nerves, and membrane conductance. Here, we describe unique morphological features of type II vestibular hair cells in mature rodents (mice and gerbils) and bats. These features are cytoplasmic processes that extend laterally from the hair cell’s base and project under type I hair cells. Closer analysis of adult mouse utricles demonstrated that the basolateral processes of type II hair cells range in shape, size, and branching, with the longest processes extending 3–4 hair cell widths. The hair cell basolateral processes synapse upon vestibular afferent nerves and receive inputs from vestibular efferent nerves. Further, some basolateral processes make physical contacts with the processes of other type II hair cells, forming some sort of network amongst type II hair cells. Basolateral processes are rare in perinatal mice and do not attain their mature form until 3–6 weeks of age. These observations demonstrate that basolateral processes are significant signaling regions of type II vestibular hair cells, and they suggest type II hair cells may directly communicate with each other, which has not been described in vertebrates. PMID:24825750
Pujol, Rémy; Pickett, Sarah B; Nguyen, Tot Bui; Stone, Jennifer S
2014-10-01
Sensory receptors in the vestibular system (hair cells) encode head movements and drive central motor reflexes that control gaze, body movements, and body orientation. In mammals, type I and II vestibular hair cells are defined by their shape, contacts with vestibular afferent nerves, and membrane conductance. Here we describe unique morphological features of type II vestibular hair cells in mature rodents (mice and gerbils) and bats. These features are cytoplasmic processes that extend laterally from the hair cell base and project under type I hair cells. Closer analysis of adult mouse utricles demonstrated that the basolateral processes of type II hair cells vary in shape, size, and branching, with the longest processes extending three to four hair cell widths. The hair cell basolateral processes synapse upon vestibular afferent nerves and receive inputs from vestibular efferent nerves. Furthermore, some basolateral processes make physical contacts with the processes of other type II hair cells, forming some sort of network among type II hair cells. Basolateral processes are rare in perinatal mice and do not attain their mature form until 3-6 weeks of age. These observations demonstrate that basolateral processes are significant signaling regions of type II vestibular hair cells and suggest that type II hair cells may directly communicate with each other, which has not been described in vertebrates. © 2014 Wiley Periodicals, Inc.
Large deformation contact mechanics of a pressurized long rectangular membrane. II. Adhesive contact
Srivastava, Abhishek; Hui, Chung-Yuen
2013-01-01
In part I of this work, we presented a theory for adhesionless contact of a pressurized neo-Hookean plane-strain membrane to a rigid substrate. Here, we extend our theory to include adhesion using a fracture mechanics approach. This theory is used to study contact hysteresis commonly observed in experiments. Detailed analysis is carried out to highlight the differences between frictionless and no-slip contact. Membrane detachment is found to be strongly dependent on adhesion: for low adhesion, the membrane ‘pinches-off’, whereas for large adhesions, it detaches unstably at finite contact (‘pull-off’). Expressions are derived for the critical adhesion needed for pinch-off to pull-off transition. Above a threshold adhesion, the membrane exhibits bistability, two stable states at zero applied pressure. The condition for bistability for both frictionless and no-slip boundary conditions is obtained explicitly. PMID:24353472
Crawshaw, Marilyn; Daniels, Ken; Adams, Damian; Bourne, Kate; van Hooff, J A P; Kramer, Wendy; Pasch, Lauri; Thorn, Petra
2015-12-01
Previous research indicates interest among some donor-conceived people, donors and recipient parents in having contact. Outcomes of such contact appear largely, but not universally, positive. This paper seeks to understand better the characteristics of associated support services. Information gathered using the authors' direct experiences and professional and personal networks in different parts of the world indicates the emergence of four main groupings: (i) publically funded services outside of treatment centers; (ii) services provided by fertility treatment or gamete bank services; (iii) services provided privately by independent psychosocial or legal practitioners; and (4) services organized by offspring and/or recipient parents. Key operational features examined were: (i) who can access such services and when; (ii) what professional standards and funding are in place to provide them; and (iii) how 'matching' and contact processes are managed. Differences appear influenced variously by the needs of those directly affected, local policies, national legislation and the interests of the fertility services which recruit gamete donors and/or deliver donor conception treatments. The paper is intended to inform fuller debate about how best to meet the needs of those seeking information and contact, the implications for the way that fertility treatment and gametes donation services are currently provided and future research needs.
Federal Register 2010, 2011, 2012, 2013, 2014
2011-02-07
...: Contact Cooling System for Aesthetic Use; Availability AGENCY: Food and Drug Administration, HHS. ACTION... entitled ``Class II Special Controls Guidance Document: Contact Cooling System for Aesthetic Use.'' This guidance document describes a means by which contact cooling systems for aesthetic use may comply with the...
Equilibrium and thermodynamic studies on biosorption of Pb(II) onto Candida albicans biomass.
Baysal, Zübeyde; Cinar, Ercan; Bulut, Yasemin; Alkan, Hüseyin; Dogru, Mehmet
2009-01-15
Biosorption of Pb(II) ions from aqueous solutions was studied in a batch system by using Candida albicans. The optimum conditions of biosorption were determined by investigating the initial metal ion concentration, contact time, temperature, biosorbent dose and pH. The extent of metal ion removed increased with increasing contact time, initial metal ion concentration and temperature. Biosorption equilibrium time was observed in 30min. The Freundlich and Langmuir adsorption models were used for the mathematical description of biosorption equilibrium and isotherm constants were also evaluated. The maximum biosorption capacity of Pb(II) on C. albicans was determined as 828.50+/-1.05, 831.26+/-1.30 and 833.33+/-1.12mgg(-1), respectively, at different temperatures (25, 35 and 45 degrees C). Biosorption showed pseudo second-order rate kinetics at different initial concentration of Pb(II) and different temperatures. The activation energy of the biosorption (Ea) was estimated as 59.04kJmol(-1) from Arrhenius equation. Using the equilibrium constant value obtained at different temperatures, the thermodynamic properties of the biosorption (DeltaG degrees , DeltaH degrees and DeltaS degrees ) were also determined. The results showed that biosorption of Pb(II) ions on C. albicans were endothermic and spontaneous. The optimum initial pH for Pb(II) was determined as pH 5.0. FTIR spectral analysis of Pb(II) adsorbed and unadsorbed C. albicans biomass was also discussed.
Frosch, Peter J; Duus Johansen, Jeanne; Schuttelaar, Marie-Louise A; Silvestre, Juan F; Sánchez-Pérez, Javier; Weisshaar, Elke; Uter, Wolfgang
2015-09-01
Contact allergy to fragrances is common, and impairs quality of life, particularly in young women. To provide current results on the prevalences of sensitization to fragrance allergens used as markers in the baseline series of most European countries. Data of patients consecutively patch tested between 2009 and 2012 in 12 European countries with fragrance allergens contained in the baseline series were collected by the European Surveillance System on Contact Allergies network and descriptively analysed. Four departments used the TRUE Test(®) system. The 'basic markers' were tested on 51 477 [fragrance mix II (FM II)] to 57 123 [Myroxylon pereirae, balsam of Peru] patients, and yielded positive reactions as follows: fragrance mix I 6.9%, Myroxylon pereirae 5.4%, FM II 3.8%, colophonium 2.6%, and hydroxyisohexyl 3-cyclohexene carboxaldehyde 1.7%, with some regional differences. Prevalences with TRUE Test(®) allergens were lower. Additional fragrances were tested on 3643 (trimethylbenzenepropanol) to 14 071 (oil of turpentine) patients, and yielded between 2.6% (Cananga odorata) and 0.7% (trimethylbenzenepropanol) positive reactions. Contact allergy to fragrances is common throughout Europe, with regional variation probably being explained by patch test technique, and differences in exposure and referral patterns. The current basic markers of fragrance sensitivity in the baseline series should be supplemented with additional fragrance allergens. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Mowitz, Martin; Svedman, Cecilia; Zimerson, Erik; Isaksson, Marléne; Pontén, Ann; Bruze, Magnus
2017-11-01
Fragrance mix I (FM I) and fragrance mix II (FM II) are included in the European baseline series as screening substances for fragrance contact allergy. To investigate the frequency of allergic reactions to FM I, FM II and their ingredients in consecutively patch tested patients. A retrospective analysis of data from 4430 patients patch tested between 2009 and 2015 was performed. Of the patients, 6.5% were FM I-positive and 3.2% were FM II-positive. Forty-five per cent of FM I-positive patients did not have positive reactions to FM I ingredients. Thirty-five per cent of those who were FM II-positive did not have positive reactions to FM II ingredients. Twenty-seven per cent of those with positive reactions to one or more of the FM I ingredients were FM I-negative, and 36% of those who had positive reactions to one or more of the FM II ingredients were FM II-negative. The allergens with the highest pick-up rates were Evernia prunastri (1.8%), cinnamal (1.3%), citral (1.2%), and hydroxyisohexyl 3-cyclohexene carboxaldehyde (1.2%). Significant differences were observed in the proportions of positive reactions to FM I, FM II, eugenol, isoeugenol, and farnesol when results from patch testing with materials from different suppliers were compared. There is a risk of missing fragrance contact allergy when testing with only the fragrance mixes is performed. The use of preparations from different suppliers may affect the patch test results. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Fawzy, Manal; Nasr, Mahmoud; Adel, Samar; Helmi, Shacker
2018-03-21
This study investigated the application of Potamogeton pectinatus for Ni(II)-ions biosorption from aqueous solutions. FTIR spectra showed that the functional groups of -OH, C-H, -C = O, and -COO- could form an organometallic complex with Ni(II)-ions on the biomaterial surface. SEM/EDX analysis indicated that the voids on the biosorbent surface were blocked due to Ni(II)-ions uptake via an ion exchange mechanism. For Ni(II)-ions of 50 mg/L, the adsorption efficiency recorded 63.4% at pH: 5, biosorbent dosage: 10 g/L, and particle-diameter: 0.125-0.25 mm within 180 minutes. A quadratic model depicted that the plot of removal efficiency against pH or contact time caused quadratic-linear concave up curves, whereas the curve of initial Ni(II)-ions was quadratic-linear convex down. Artificial neural network with a structure of 5 - 6 - 1 was able to predict the adsorption efficiency (R 2 : 0.967). The relative importance of inputs was: initial Ni(II)-ions > pH > contact time > biosorbent dosage > particle-size. Freundlich isotherm described well the adsorption mechanism (R 2 : 0.974), which indicated a multilayer adsorption onto energetically heterogeneous surfaces. The net cost of using P. pectinatus for the removal of Ni(II)-ions (4.25 ± 1.26 mg/L) from real industrial effluents within 30 minutes was 3.4 $USD/m 3 .
A possible association of idiopathic osteosclerosis with excessive occlusal forces.
Misirlioglu, Melda; Nalcaci, Rana; Baran, Ilgi; Adisen, Mehmet Zahit; Yilmaz, Selmi
2014-03-01
The aim of the study was to determine the relationship between idiopathic osteosclerotic lesions and occlusal forces using the T-Scan II computerized occlusal analysis device, and to test the sensitivity of the system in occlusal analysis. The study was conducted with 21 volunteers with idiopathic osteosclerosis (IO; 14 women, 7 men) aged between 17 and 62 years (mean 29.95). For every patient, seven or eight recordings were made with the T-Scan II occlusal analysis device in maximum intercuspation, and the last two (excluding any with technical problems) were chosen for evaluation. For each lesion-related area, the distribution of high occlusal forces from two different movies was analyzed. In 18 patients (85.71%), lesions were observed in an area of high occlusal force, and in 13 patients (61.9%), the lesions were located at the first area subjected to high occlusal forces. The percentage distribution of high forces at a lesion related area ranged from 0% to 88%. On average, the high forces at an osteosclerotic lesion area accounted for 20% of the maximum total force. No statistical differences were observed between the measurements of the two selected recordings (P > .05). The findings of this study suggest a possible relationship between IO and occlusal forces and primary contacts. T-Scan II was found to be a successful diagnostic device for detecting primary contacts and excessive occlusal forces.
Murray, J S; Fois, S D S; Schountz, T; Ford, S R; Tawde, M D; Brown, J C; Siahaan, T J
2002-03-01
Several major histocompatibility complex class II (MHC II) complexes with known minimal immunogenic peptides have now been solved by X-ray crystallography. Specificity pockets within the MHC II binding groove provide distinct peptide contacts that influence peptide conformation and define the binding register within different allelic MHC II molecules. Altering peptide ligands with respect to the residues that contact the T-cell receptor (TCR) can drastically change the nature of the ensuing immune response. Here, we provide an example of how MHC II (I-A) molecules may indirectly effect TCR contacts with a peptide and drive functionally distinct immune responses. We modeled the same immunogenic 12-amino acid peptide into the binding grooves of two allelic MHC II molecules linked to distinct cytokine responses against the peptide. Surprisingly, the favored conformation of the peptide in each molecule was distinct with respect to the exposure of the N- or C-terminus of the peptide above the MHC II binding groove. T-cell clones derived from each allelic MHC II genotype were found to be allele-restricted with respect to the recognition of these N- vs. C-terminal residues on the bound peptide. Taken together, these data suggest that MHC II alleles may influence T-cell functions by restricting TCR access to specific residues of the I-A-bound peptide. Thus, these data are of significance to diseases that display genetic linkage to specific MHC II alleles, e.g. type 1 diabetes and rheumatoid arthritis.
Implementing Tuberculosis Close-contact Investigation in a Tertiary Hospital in Iran.
Shamaei, Masoud; Esmaeili, Shahrbanoo; Marjani, Majid; Tabarsi, Payam
2018-01-01
Close contact investigation is the essential key in tuberculosis (TB) case finding and an effective strategy for TB control program within any society. In this prospective study, 1186 close family contacts of hospitalized TB patients (index) in a referral TB hospital in Tehran-Iran were passively studied. These people were studied to rollout TB infection and disease. Demographic characteristics, clinical and laboratory data of these individuals were reviewed and summarized for analysis. A total of 886 (74.4%) close-family contacts completed their investigation. The index TB patients of these individuals were sputum smear negative for acid-fast bacilli in 137 cases (11.6%) and the rest were smear positive. A total of 610 (68.8%) close-family contact ruled out for TB infection or disease (Group I). A total of 244 cases (27.5%) had latent TB infection (Group II) and active TB (Group III) was confirmed in 32 cases (3.6%). A significant difference was shown for female gender, signs and symptoms, family size, and positive radiological finding between Group I and Group II. The study of index parameter including positive sputum smear/culture did not reveal any significant difference, but positive cavitary lesion significantly more has seen in active TB group ( P = 0.004). This study emphasizes on sign and symptoms and radiological finding in TB contact investigation, where index parameters including positive smear/culture, does not implicate any priority. Although cavitary lesions in index patient have more accompanied by active TB, close contact study should include all of TB indexes. This investigation should include chest radiography for these individuals.
Non Contacting Evaluation of Strains and Cracking Using Optical and Infrared Imaging Techniques
1988-08-22
Compatible Zenith Z-386 microcomputer with plotter II. 3-D Motion Measurinq System 1. Complete OPTOTRAK three dimensional digitizing system. System includes...acquisition unit - 16 single ended analog input channels 3. Data Analysis Package software (KINEPLOT) 4. Extra OPTOTRAK Camera (max 224 per system
30 CFR 204.205 - How do I obtain accounting and auditing relief?
Code of Federal Regulations, 2010 CFR
2010-07-01
..., address, phone number, and contact name; and (ii) The specific MMS lease number and agreement number, if... contain: (i) Your company name, MMS-assigned payor code, address, phone number, and contact name; (ii) The...
Turan, Nurdan Gamze; Ozgonenel, Okan
2013-01-01
An intensive study has been made of the removal efficiency of Cu(II) from industrial leachate by biosorption of montmorillonite. A 24 factorial design and cascade forward neural network (CFNN) were used to display the significant levels of the analyzed factors on the removal efficiency. The obtained model based on 24 factorial design was statistically tested using the well-known methods. The statistical analysis proves that the main effects of analyzed parameters were significant by an obtained linear model within a 95% confidence interval. The proposed CFNN model requires less experimental data and minimum calculations. Moreover, it is found to be cost-effective due to inherent advantages of its network structure. Optimization of the levels of the analyzed factors was achieved by minimizing adsorbent dosage and contact time, which were costly, and maximizing Cu(II) removal efficiency. The suggested optimum conditions are initial pH at 6, adsorbent dosage at 10 mg/L, and contact time at 10 min using raw montmorillonite with the Cu(II) removal of 80.7%. At the optimum values, removal efficiency was increased to 88.91% if the modified montmorillonite was used. PMID:24453833
Handling times and saturating transmission functions in a snail-worm symbiosis.
Hopkins, Skylar R; McGregor, Cari M; Belden, Lisa K; Wojdak, Jeremy M
2018-06-16
All dynamic species interaction models contain an assumption that describes how contact rates scale with population density. Choosing an appropriate contact-density function is important, because different functions have different implications for population dynamics and stability. However, this choice can be challenging, because there are many possible functions, and most are phenomenological and thus difficult to relate to underlying ecological processes. Using one such phenomenological function, we described a nonlinear relationship between field transmission rates and host density in a common snail-oligochaete symbiosis. We then used a well-known contact function from predator-prey models, the Holling Type II functional response, to describe and predict host snail contact rates in the laboratory. The Holling Type II functional response accurately described both the nonlinear contact-density relationship and the average contact duration that we observed. Therefore, we suggest that contact rates saturate with host density in this system because each snail contact requires a non-instantaneous handling time, and additional possible contacts do not occur during that handling time. Handling times and nonlinear contact rates might also explain the nonlinear relationship between symbiont transmission and snail density that we observed in the field, which could be confirmed by future work that controls for other potential sources of seasonal variation in transmission rates. Because most animal contacts are not instantaneous, the Holling Type II functional response might be broadly relevant to diverse host-symbiont systems.
Lunardi, Letícia Helena; Arroyo, Danielle; Andrade Sobrinho, Marcelo Vicente de; Lipener, César; Rosa, Juliana Maria da Silva
2016-04-01
Keratoconus is characterized by bilateral asymmetrical corneal ectasia that leads to inferior stromal thinning and corneal protrusion. There is currently a lack of consensus regarding the most efficacious method for fitting contact lenses in patients with keratoconus, given the various topographical patterns and evolution grades observed in affected populations. The purpose of the present study was to evaluate the association between keratoconus evolution grade and topography pattern and the type and design of fitted contact lens. We performed a retrospective analysis of contact lenses fitted in a total of 185 patients with keratoconus (325 eyes). Keratoconus was classified as either grade I, II, III, or IV based on keratometry and cone morphology (nipple, oval, globus, or indeterminate) results. A total of 325 eyes were evaluated in the present study. Of the 62 eyes classified as grade I, 66.1% were fitted with monocurve contact lenses. Of the 162 eyes classified as grade I and II, 51%, 30%, and 19% were fitted with adapted monocurve rigid gas-permeable contact lenses (RGPCL), bicurve lenses, and others lens types, respectively. Bicurve lenses were fitted in 52.1% and 62.2% of eyes classified as grade III and IV, respectively. Of the eyes classified as grade III and IV, monocurve and bicurve RGPCL were fitted in 26% and 55%, respectively. In eyes with oval keratoconus, 45%, 35%, and 20% were fitted with monocurve lenses, bicurve lenses, and other lens types, respectively. In eyes with round cones (nipple morphology), 55%, 30%, and 15% were fitted with bicurve lenses, monocurve lenses, and other lens types, respectively. Monocurve RGPCL were most frequently fitted in patients with mild to moderate keratoconus and oval cones morphology, while bicurve lenses were more frequently fitted in patients with severe and advanced keratoconus. This was probably because bicurve lenses are more appropriate for round cones due to increased corneal asphericity.
Branch-point energies and the band-structure lineup at Schottky contacts and heterostrucures
NASA Astrophysics Data System (ADS)
Mönch, Winfried
2011-06-01
Empirical branch-point energies of Si, the group-III nitrides AlN, GaN, and InN, and the group-II and group-III oxides MgO, ZnO, Al2O3 and In2O3 are determined from experimental valance-band offsets of their heterostructures. For Si, GaN, and MgO, these values agree with the branch-point energies obtained from the barrier heights of their Schottky contacts. The empirical branch-point energies of Si and the group-III nitrides are in very good agreement with results of previously published calculations using quite different approaches such as the empirical tight-binding approximation and modern electronic-structure theory. In contrast, the empirical branch-point energies of the group-II and group-III oxides do not confirm the respective theoretical results. As at Schottky contacts, the band-structure lineup at heterostructures is also made up of a zero-charge-transfer term and an intrinsic electric-dipole contribution. Hence, valence-band offsets are not equal to the difference of the branch-point energies of the two semiconductors forming the heterostructure. The electric-dipole term may be described by the electronegativity difference of the two solids in contact. A detailed analysis of experimental Si Schottky barrier heights and heterostructure valence-band offsets explains and proves these conclusions.
NASA Astrophysics Data System (ADS)
Sreejith, S. S.; Mohan, Nithya; Kurup, M. R. Prathapachandra
2018-02-01
A trinulcear Zn2La Schiff base complex was synthesized using slow-solvent evaporation technique from a Zn(II) mononuclear metalloligand by 2:1 addition with La(NO3)3 salt. Single crystal XRD analysis revealed a rare nitrato bridged trinuclear entity which is seldom seen in these class of ligand systems. Qualitative and quantitative analysis of intermolecular interactions/short contacts were done using Hirshfeld surface and 2D finger print analysis. The thermally stable, blue luminescent compound exhibits internal heavy atom effect thereby quenching the emission intensity of the ligand. DFT calculations were performed on the compound to analyze frontier orbitals and also ESP plots were used to monitor nucleophilic/electrophilic regions on the compound and its implications on hydrogen bonding. A comparison of the bond orders and atomic charges on the trinuclear compound and the Zn(II) metalloligand precursor was performed to substantiate the formation of the trinuclear product through ligand exchange.
Investigation of fretting behaviour in pressure armour layers of flexible pipes
NASA Astrophysics Data System (ADS)
Don Rasika Perera, Solangarachchige
The incidence of fretting damage in the pressure armour wires of flexible pipes used in offshore oil explorations has been investigated. A novel experimental facility which is capable of simulating nub and valley contact conditions of interlocking wire winding with dynamic slip, representative of actual pipe loading, has been developed. The test set-up is equipped with a state of the art data acquisition system and a controller with transducers to measure and control the normal load, slip amplitude and friction force at the contact, in addition to the hoop stress in the wire. Tests were performed with selected loading and the fretted regions were examined using optical microscopy techniques. Results show that the magnitude of contact loading and the slip amplitude have a distinct influence on surface damage. Surface cracks originated from a fretting scar were observed at high contact loads in mixed slip sliding while surface damage predominantly due to wear was observed under gross slip. The position of surface cracks and the wear profile have been related to the contact pressure distribution. The evolution of friction force and surface damage under different slip and normal pressure conditions has been analysed. A fracture mechanics based numerical procedure has been developed to analyse the fretting damage behaviour. A severity parameter is proposed in order to ascertain whether the crack growth is in mode I or mode II cracking. The analysis show the influence of mode II cracking in the early stages of crack growth following which the crack deviates in the mode I direction making mode I the dominant crack propagation mechanism. The crack path determined by the numerical procedure correlates well with the experimental results. A numerical analysis was carried out for the fretting fatigue condition where a cyclic bulk stress superimposes with the friction force. The analysis correlates well with short crack growth behaviour. The analysis confirms that fretting is a significant factor that should be taken into account in design and operation of the pressure armour wires of flexible pipes at high contact pressure if the bulk cyclic load superimposes with the friction force. As predicted by the numerical procedure and further by experimental investigations, the surface cracks initiating on the wire in this condition are self arresting after propagating into a certain depth.
[Cyclic fatigue of Vita mark II machinable ceramics under Hertzian's contact].
Liu, Wei-Cai; Zhang, Zhi-Shen; Huang, Cheng-Min; Chao, Yong-Lie; Wan, Qian-Bing
2006-08-01
To investigate the cyclic fatigue modes of Vita mark II machinable ceramics under Hertzian's contact. Hertzian's contact technique (WC spheres r = 3.18 mm) was used to investigate the cyclic fatigue of Vita mark II machinable ceramic. All specimens were fatigued by cyclic loading in moist environment, furthermore, surviving strength was examined by three point test and morphology damage observation. In homogeneous Vita mark II machinable ceramics, two fatigue damage modes existed after cyclic loading with spheres under moist environment, including conventional tensile-driven cone cracking (brittle mode) and shear-driven microdamage accumulation (quasi-plastic mode). The latter generated radial cracks and deeply penetrating secondary cone crack. Initial strength degradation were caused by the cone cracks, subsequent and much more deleterious loss was caused by radial cracks. Cyclic fatigue modes of Vita mark II machinable ceramics includes brittle and quasi-plastic mode.
Tanko, Zita; Shab, Arna; Diepgen, Thomas Ludwig; Weisshaar, Elke
2009-06-01
Fragrances are very common in everyday products. A metalworker with chronic hand eczema and previously diagnosed type IV sensitizations to epoxy resin, balsam of Peru, fragrance mix and fragrance mix II was diagnosed with additional type IV sensitizations to geraniol, hydroxycitronellal, lilial, tree moss, oak moss absolute, citral, citronellol, farnesol, Lyral, fragrance mix II and fragrance mix (with sorbitan sesquioleate). In addition, a type IV sensitization to the skin protection cream containing geraniol and citronellol used at the workplace was detected, and deemed occupationally relevant in this case. The patient could have had contact to fragrances through private use of cosmetics and detergents. On the other hand, the fragrance-containing skin protection cream supports occupational exposure. This case report demonstrates that fragrance contact allergy has to be searched for and clarified individually, which requires a thorough history and a detailed analysis of the work place.
Nonlinear dynamics of planetary gears using analytical and finite element models
NASA Astrophysics Data System (ADS)
Ambarisha, Vijaya Kumar; Parker, Robert G.
2007-05-01
Vibration-induced gear noise and dynamic loads remain key concerns in many transmission applications that use planetary gears. Tooth separations at large vibrations introduce nonlinearity in geared systems. The present work examines the complex, nonlinear dynamic behavior of spur planetary gears using two models: (i) a lumped-parameter model, and (ii) a finite element model. The two-dimensional (2D) lumped-parameter model represents the gears as lumped inertias, the gear meshes as nonlinear springs with tooth contact loss and periodically varying stiffness due to changing tooth contact conditions, and the supports as linear springs. The 2D finite element model is developed from a unique finite element-contact analysis solver specialized for gear dynamics. Mesh stiffness variation excitation, corner contact, and gear tooth contact loss are all intrinsically considered in the finite element analysis. The dynamics of planetary gears show a rich spectrum of nonlinear phenomena. Nonlinear jumps, chaotic motions, and period-doubling bifurcations occur when the mesh frequency or any of its higher harmonics are near a natural frequency of the system. Responses from the dynamic analysis using analytical and finite element models are successfully compared qualitatively and quantitatively. These comparisons validate the effectiveness of the lumped-parameter model to simulate the dynamics of planetary gears. Mesh phasing rules to suppress rotational and translational vibrations in planetary gears are valid even when nonlinearity from tooth contact loss occurs. These mesh phasing rules, however, are not valid in the chaotic and period-doubling regions.
Removal of lead (II) ions from aqueous solutions onto activated carbon derived from waste biomass.
Erdem, Murat; Ucar, Suat; Karagöz, Selhan; Tay, Turgay
2013-01-01
The removal of lead (II) ions from aqueous solutions was carried out using an activated carbon prepared from a waste biomass. The effects of various parameters such as pH, contact time, initial concentration of lead (II) ions, and temperature on the adsorption process were investigated. Energy Dispersive X-Ray Spectroscopy (EDS) analysis after adsorption reveals the accumulation of lead (II) ions onto activated carbon. The Langmuir and Freundlich isotherm models were applied to analyze equilibrium data. The maximum monolayer adsorption capacity of activated carbon was found to be 476.2 mg g⁻¹. The kinetic data were evaluated and the pseudo-second-order equation provided the best correlation. Thermodynamic parameters suggest that the adsorption process is endothermic and spontaneous.
Finite element analysis of the end notched flexure specimen for measuring Mode II fracture toughness
NASA Technical Reports Server (NTRS)
Gillespie, J. W., Jr.; Carlsson, L. A.; Pipes, R. B.
1986-01-01
The paper presents a finite element analysis of the end-notched flexure (ENF) test specimen for Mode II interlaminar fracture testing of composite materials. Virtual crack closure and compliance techniques employed to calculate strain energy release rates from linear elastic two-dimensional analysis indicate that the ENF specimen is a pure Mode II fracture test within the constraints of small deflection theory. Furthermore, the ENF fracture specimen is shown to be relatively insensitive to process-induced cracks, offset from the laminate midplane. Frictional effects are investigated by including the contact problem in the finite element model. A parametric study investigating the influence of delamination length, span, thickness, and material properties assessed the accuracy of beam theory expressions for compliance and strain energy release rate, GII. Finite element results indicate that data reduction schemes based upon beam theory underestimate GII by approximately 20-40 percent for typical unidirectional graphite fiber composite test specimen geometries. Consequently, an improved data reduction scheme is proposed.
Patch tests with fragrance mix II and its components.
Pónyai, Györgyi; Németh, Ilona; Altmayer, Anita; Nagy, Gabriella; Irinyi, Beatrix; Battyáni, Zita; Temesvári, Erzsébet
2012-01-01
Fragrance mix II (FM II) was initiated to detect contact hypersenstitivity (CH) to fragrances that could not have been identified previously. The aim of this multicenter study was to map the frequency of CH to FM II and its components in Hungary. Six centers participated in the survey from 2009 to 2010. A total off 565 patients (434 women and 131 men) with former skin symptoms provoked by scented products were patch tested. The tests were performed with Brial GmbH D-Greven allergens. In the environmental patch test series, FM II, FM I, Myroxylon pereirae, colophonium, wood-tar mix, propolis, and sesquiterpene lactone mix were tested as fragrance allergens. The FM II components (citral, farnesol, coumarin, citronellol, α-hexyl-cinnamaldehyde, and hydroxy-isohexyl-3-cyclohexene-carboxaldehyde [Lyral]) were also tested. Contact hypersenstitivity to any fragrances was detected in 28.8%, to FM II in 17.2% of the patients. Contact hypersenstitivity to hydroxy-isohexyl-3-cyclohexene-carboxaldehyde was observed in 7.3%, to coumarin in 5.1%, to α-hexyl-cinnamaldehyde in 3.5%, to citral in 3.4%, to farnesol in 2.5%, and to citronellol in 1.2%. Of the FM II-positive cases, 48.4% showed isolated CH reaction. The frequency of CH to FM II is 17.2% in the tested, selected Hungarian population. The CH to FM II and its components could not have been revealed without the present test materials.
Effects of metal-soil contact time on the extraction of mercury from soils.
Ma, Lan; Zhong, Huan; Wu, Yong-Gui
2015-03-01
To investigate the mercury aging process in soils, soil samples were spiked with inorganic mercury (Hg(II)) or methylated mercury (MeHg) and incubated for 2, 7, 14 or 28 days in the laboratory. Potential availability of mercury, assessed by bovine serum albumin (BSA) or calcium chloride (CaCl2) extraction, decreased by 2-19 times for Hg(II) or 2-6 times for MeHg, when the contact time increased from 2 to 28 days. Decreased Hg(II) extraction could be explained by Hg(II) geochemical fractionation, i.e., Hg(II) migrated from more mobile fractions (water soluble and stomach acid soluble fractions) to refractory ones (organo-complexed, strongly complexed and residual fractions) over time, resulting in more stable association of Hg(II) with soils. In addition, decrease of mercury extraction was more evident in soils with lower organic content in most treatments, suggesting that organic matter may potentially play an important role in mercury aging process. In view of the significant decreased Hg(II) or MeHg extraction with prolonged contact time, mercury aging process should be taken into account when assessing risk of mercury in contaminated soils.
Lee, Hyemin; Cha, Jooly; Chun, Youn-Sic; Kim, Minji
2018-06-19
The occlusal registration of virtual models taken by intraoral scanners sometimes shows patterns which seem much different from the patients' occlusion. Therefore, this study aims to evaluate the accuracy of virtual occlusion by comparing virtual occlusal contact area with actual occlusal contact area using a plaster model in vitro. Plaster dental models, 24 sets of Class I models and 20 sets of Class II models, were divided into a Molar, Premolar, and Anterior group. The occlusal contact areas calculated by the Prescale method and the virtual occlusion by scanning method were compared, and the ratio of the molar and incisor area were compared in order to find any particular tendencies. There was no significant difference between the Prescale results and the scanner results in both the molar and premolar groups (p = 0.083 and 0.053, respectively). On the other hand, there was a significant difference between the Prescale and the scanner results in the anterior group with the scanner results presenting overestimation of the occlusal contact points (p < 0.05). In Molars group, the regression analysis shows that the two variables express linear correlation and has a linear equation with a slope of 0.917. R 2 is 0.930. Groups of Premolars and Anteriors had a week linear relationship and greater dispersion. Difference between the actual and virtual occlusion revealed in the anterior portion, where overestimation was observed in the virtual model obtained from the scanning method. Nevertheless, molar and premolar areas showed relatively accurate occlusal contact area in the virtual model.
Bermond, Gérald; Ciosi, Marc; Lombaert, Eric; Blin, Aurélie; Boriani, Marco; Furlan, Lorenzo; Toepfer, Stefan; Guillemaud, Thomas
2012-01-01
The western corn rootworm, Diabrotica virgifera virgifera (Coleoptera: Chrysomelidae), is one of the most destructive pests of corn in North America and is currently invading Europe. The two major invasive outbreaks of rootworm in Europe have occurred, in North-West Italy and in Central and South-Eastern Europe. These two outbreaks originated from independent introductions from North America. Secondary contact probably occurred in North Italy between these two outbreaks, in 2008. We used 13 microsatellite markers to conduct a population genetics study, to demonstrate that this geographic contact resulted in a zone of admixture in the Italian region of Veneto. We show that i) genetic variation is greater in the contact zone than in the parental outbreaks; ii) several signs of admixture were detected in some Venetian samples, in a Bayesian analysis of the population structure and in an approximate Bayesian computation analysis of historical scenarios and, finally, iii) allelic frequency clines were observed at microsatellite loci. The contact between the invasive outbreaks in North-West Italy and Central and South-Eastern Europe resulted in a zone of admixture, with particular characteristics. The evolutionary implications of the existence of a zone of admixture in Northern Italy and their possible impact on the invasion success of the western corn rootworm are discussed. PMID:23189184
Quantitation of total protein deposits on contact lenses by means of amino acid analysis.
Yan, G; Nyquist, G; Caldwell, K D; Payor, R; McCraw, E C
1993-04-01
This study was done to characterize and quantify the protein deposits on worn contact lenses and to measure the residual deposits after extraction in 2% sodium dodecyl sulfate and the total protein deposits on worn vifilcon, atlafilcon, and tefilcon lenses (Food and Drug Administration Types IV, II, and I, respectively). Contact lens extracts were separated with gel electrophoresis, and the amount of protein was estimated after silver staining and densitometry. To determine the residual deposits, the contact lenses were hydrolyzed, and amino acid analysis was carried out by reverse-phase high-performance liquid chromatography after precolumn derivatization with phenylisothiocyanate. Refinement of the hydrolysis conditions was undertaken to minimize interference by the lens polymers. The extraction removed only approximately 25% of the protein deposits. Mild hydrolytic conditions, 20 hr in 6 N HCl at 105 degrees C, were found to cause minimal polymer interference. Of the 350, 10, and 20 micrograms of protein typically determined on whole vifilcon, atlafilcon, and tefilcon lenses, the polymers were estimated to account for 4, 0.5, and less than 0.4 micrograms, respectively. Hydrolysis of worn contact lenses with subsequent amino acid separation can be applied to determine the total protein deposits without the uncertainty inherent in extraction of the deposits.
NASA Astrophysics Data System (ADS)
Khalil, Tarek E.; Elbadawy, Hemmat A.; El-Dissouky, Ali
2018-02-01
A new chelating resin, 1,8-(3,6-dithiaoctyl)-4-polyvinylbenzenesulphonate (dpvbs) has been synthesized by coupling Amberlite XAD-16 with (2,2‧-ethylenedithio) diethanol using pyridine/CH2Cl2 mixture as a solvent. The chelating resin and its metallopolymer Cu(II), Ni(II), Co(II) and Fe(III) complexes have been synthesized and characterized by EDS, SEM, XPS, elemental analysis, spectral (IR, UV/Vis, EPR). The thermal analysis of the resin and its metallopolymer complexes indicated an endothermic spontaneous sorption mechanism with the liberation of water of hydration of the metal ions and that adsorbed by the free resin. At the solid liquid interface, the degrees of freedom increased during the sorption of the metal ions onto the resin. The surface area of polymer support and its metallopolymer complexes are estimated by (BJH) method. The batch equilibrium method was used for studying the metal sorption and selectivity at different pH values and different contact times at room temperature. ICP-AES was used to estimate the metal capacity of the resin for sorption of Cu(II), Ni(II), Co(II) and Fe(III) from aqueous solutions utilizing the batch equilibrium method. The sorption tendency of the metal ions by the resin was found to be: Cu(II) > Fe(III) > Co(II) > Ni(II). Adsorption kinetics was found to be fit the pseudo-second order model.
Riveline, D; Zamir, E; Balaban, N Q; Schwarz, U S; Ishizaki, T; Narumiya, S; Kam, Z; Geiger, B; Bershadsky, A D
2001-06-11
The transition of cell-matrix adhesions from the initial punctate focal complexes into the mature elongated form, known as focal contacts, requires GTPase Rho activity. In particular, activation of myosin II-driven contractility by a Rho target known as Rho-associated kinase (ROCK) was shown to be essential for focal contact formation. To dissect the mechanism of Rho-dependent induction of focal contacts and to elucidate the role of cell contractility, we applied mechanical force to vinculin-containing dot-like adhesions at the cell edge using a micropipette. Local centripetal pulling led to local assembly and elongation of these structures and to their development into streak-like focal contacts, as revealed by the dynamics of green fluorescent protein-tagged vinculin or paxillin and interference reflection microscopy. Inhibition of Rho activity by C3 transferase suppressed this force-induced focal contact formation. However, constitutively active mutants of another Rho target, the formin homology protein mDia1 (Watanabe, N., T. Kato, A. Fujita, T. Ishizaki, and S. Narumiya. 1999. Nat. Cell Biol. 1:136-143), were sufficient to restore force-induced focal contact formation in C3 transferase-treated cells. Force-induced formation of the focal contacts still occurred in cells subjected to myosin II and ROCK inhibition. Thus, as long as mDia1 is active, external tension force bypasses the requirement for ROCK-mediated myosin II contractility in the induction of focal contacts. Our experiments show that integrin-containing focal complexes behave as individual mechanosensors exhibiting directional assembly in response to local force.
Patch testing with hair cosmetic series in Europe: a critical review and recommendation.
Uter, Wolfgang; Bensefa-Colas, Lynda; Frosch, Peter; Giménez-Arnau, Ana; John, Swen M; Lepoittevin, Jean-Pierre; Lidén, Carola; White, Ian R; Duus Johansen, Jeanne
2015-08-01
Many key ingredients of hair cosmetics (in particular, dyes, bleaches, and hair-styling agents) are potent (strong to extreme) contact allergens. Some heterogeneity is apparent from published results concerning the range of allergens for which patch testing is important. The objective of the present review was to collect information on the current practice of using 'hair cosmetic series', and discuss this against the background of evidence concerning consumer/professional exposure and regulatory aspects to finally derive a recommendation for a 'European hair cosmetic series'. The methods involved (i) a survey targeting all members of the COST action 'StanDerm' (TD1206) consortium, (ii) analysis of data in the database of the European Surveillance System on Contact Allergies (ESSCA), and (iii) literature review. Information from 19 European countries was available, partly from national networks, and partly from one or several departments of dermatology or, occasionally, occupational medicine. Apart from some substances being tested only in single departments, a broad overlap regarding 'important' allergens was evident. Some of the substances are no longer permitted for use in cosmetics (Annex II of the Cosmetics Regulation). An up-to-date 'European hair cosmetics series', as recommended in the present article, should (i) include broadly used and/or potent contact allergens, (ii) eliminate substances of only historical concern, and (iii) be continually updated as new evidence emerges. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Soudani, S.; Ferretti, V.; Jelsch, C.
The chemical preparation, crystal structure, Hirshfeld surface analysis and spectroscopic characterization of the novel cadmium (II) 4-hydroxy-1-methylpiperidine complex, Cd{sub 4}Cl{sub 10}(C{sub 6}H{sub 14}NO){sub 2}·2H{sub 2}O, have been reported. The atomic arrangement can be described as built up by an anionic framework, formed by edge sharing CdCl{sub 6} and CdCl{sub 5}O octahedral linear chains spreading along the a-axis. These chains are interconnected by water molecules via O–H⋯Cl and O–H⋯O hydrogen bonds to form layers parallel to (011) plane. The organic cations are inserted between layers through C–H⋯Cl hydrogen bonds. Investigation of intermolecular interactions and crystal packing via Hirshfeld surface analysis revealsmore » that the H{sub C}⋯Cl and H{sub C}⋯H{sub C} intermolecular interactions are the most abundant contacts of the organic cation in the crystal packing. The statistical analysis of crystal contacts reveals the driving forces in the packing formation. The {sup 13}C and {sup 15}N CP-MAS NMR spectra are in agreement with the X-ray structure. The vibrational absorption bands were identified by infrared spectroscopy. DFT calculations allowed the attribution of the NMR peaks and of the IR bands.« less
21 CFR 886.5928 - Soft (hydrophilic) contact lens care products.
Code of Federal Regulations, 2011 CFR
2011-04-01
... (hydrophilic) contact lens. This includes all solutions and tablets used together with soft (hydrophilic) contact lenses and heat disinfecting units intended to disinfect a soft (hydrophilic) contact lens by means of heat. (b) Classification. Class II (Special Controls) Guidance Document: “Guidance for Industry...
21 CFR 886.5928 - Soft (hydrophilic) contact lens care products.
Code of Federal Regulations, 2012 CFR
2012-04-01
... (hydrophilic) contact lens. This includes all solutions and tablets used together with soft (hydrophilic) contact lenses and heat disinfecting units intended to disinfect a soft (hydrophilic) contact lens by means of heat. (b) Classification. Class II (Special Controls) Guidance Document: “Guidance for Industry...
21 CFR 886.5928 - Soft (hydrophilic) contact lens care products.
Code of Federal Regulations, 2013 CFR
2013-04-01
... (hydrophilic) contact lens. This includes all solutions and tablets used together with soft (hydrophilic) contact lenses and heat disinfecting units intended to disinfect a soft (hydrophilic) contact lens by means of heat. (b) Classification. Class II (Special Controls) Guidance Document: “Guidance for Industry...
21 CFR 886.5928 - Soft (hydrophilic) contact lens care products.
Code of Federal Regulations, 2014 CFR
2014-04-01
... (hydrophilic) contact lens. This includes all solutions and tablets used together with soft (hydrophilic) contact lenses and heat disinfecting units intended to disinfect a soft (hydrophilic) contact lens by means of heat. (b) Classification. Class II (Special Controls) Guidance Document: “Guidance for Industry...
Porous cellulosic adsorbent for the removal of Cd (II), Pb(II) and Cu(II) ions from aqueous media
NASA Astrophysics Data System (ADS)
Barsbay, Murat; Kavaklı, Pınar Akkaş; Tilki, Serhad; Kavaklı, Cengiz; Güven, Olgun
2018-01-01
The main objective of this work is to prepare a renewable cellulosic adsorbent by γ-initiated grafting of poly(glycidyl methacrylate) (PGMA) from cellulose substrate and subsequent modification of PGMA with chelating species, iminodiacetic acid (IDA), for Cd (II), Pb(II) and Cu(II) removal from aqueous media. Modification of PGMA grafted cellulose with IDA in aqueous solution under mild conditions has proceeded efficiently to yield a natural-based and effective porous adsorbent with well-defined properties as provided by the controlled polymerization technique, namely RAFT, applied during the radiation-induced graft copolymerization step and with sufficient degree of IDA immobilization as confirmed by XPS, FTIR, contact angle measurements and elemental analysis. In order to examine the Cd (II), Pb(II) and Cu(II) removing performance of the resulting adsorbent, batch experiments were carried out by ICP-MS. The adsorption capacities were determined as 53.4 mg Cd(II)/g polymer, 52.0 mg Pb(II)/g polymer and 69.6 mg Cu(II)/g polymer at initial feed concentration of 250 ppm, showing the promising potential of the natural-based adsorbent to steadily and efficiently chemisorb toxic metal ions.
Warmuth, A. R.; Sun, W.; Shipway, P. H.
2016-01-01
This paper investigates the effect of contact geometry, temperature and displacement amplitude on the fretting behaviour of an aero-turbo oil lubricated cylinder-on-flat contact. To be effective, the lubricant needed both to penetrate the contact and then offer protection. Lubricant penetration into the fretting contact is found to be controlled by two physical parameters, namely (i) the width of the contact that remains covered throughout the fretting test and (ii) the lubricant viscosity. The protection offered by the lubricant (assuming that it has successfully penetrated the contact) is influenced by four physical parameters, namely (i) lubricant viscosity, (ii) traverse velocity, (iii) nominal contact pressure, and (iv) chemical effects. The relationship between the three experimental parameters which were varied in the programme of work (temperature, fretting displacement and cylinder radius) and physical parameters which influence the protection offered by the lubricant film can be competing, and therefore complex wear behaviour is observed. The roles of the various parameters in controlling the wear behaviour are presented in a coherent physical framework. PMID:27853530
NASA Astrophysics Data System (ADS)
Ben Nasr, M.; Soudani, S.; Lefebvre, F.; Jelsch, C.; Ben Nasr, C.
2017-06-01
The Zn(II) complex with the monodentate ligand 4-fluoroaniline, ZnCl2(C6H4FNH2)2, has been prepared and characterized by single crystal X-ray diffraction, solid state nuclear magnetic resonance, infrared spectroscopy and differential scanning calorimetry. The Zn(II) ion is tetracoordinated by two nitrogen atoms of two monodentate 4-fluoroaniline ligands and two chlorine atoms. In the molecular arrangement, the ZnCl2(C6H4FNH2)2 entities are interconnected via Nsbnd H⋯Cl hydrogen bonds to form layers parallel to the (a, b) plane. The nature and proportion of contacts in the crystal packing were investigated through the Hirshfeld surfaces. The crystal is mainly maintained by electrostatic attractions Cl- … Hsbnd N and by extensive hydrophobic contacts as revealed by the Hirshfeld 2D fingerprint plots and statistical analysis. The13C and 19F CP-MAS NMR spectra are in agreement with the X-ray structure and confirm the phase purity of the crystalline sample. The vibrational absorption bands were identified by infrared spectroscopy. A calorimetric study shows that the title compound is stable until 262.5 °C.
Removal of Cu(II) and Pb(II) from Aqueous Solutions Using Nanoporous Materials
NASA Astrophysics Data System (ADS)
Dutta, Debajani; Roy, Sushanta Kumar; Das, Bodhaditya; Talukdar, Anup K.
2018-05-01
The present work deals with the adsorption of Cu2+ and Pb2+ on zeolites (ZSM-5, mordenite) and mesoporous materials (MCM-48, MCM-41). The characterization of the synthesized samples was performed by means of XRD, SEM, and thermogravimetric analysis. The batch method was employed to study the influence of adsorbent nature, contact time, initial metal ion concentration, and adsorbent load. The adsorption on MCM-48 follows a pseudo-second-order kinetic model. This material was found to be more effective for the removal of lead in a batch process as compared to the other adsorbents and the removal efficiency of the materials for Pb(II) followed the order MCM-48 > mordenite > ZSM-5 > MCM-41 and that for Cu(II) followed the order ZSM-5 > mordenite > MCM-41 > MCM-48.
Yetilmezsoy, Kaan; Demirel, Sevgi
2008-05-30
A three-layer artificial neural network (ANN) model was developed to predict the efficiency of Pb(II) ions removal from aqueous solution by Antep pistachio (Pistacia Vera L.) shells based on 66 experimental sets obtained in a laboratory batch study. The effect of operational parameters such as adsorbent dosage, initial concentration of Pb(II) ions, initial pH, operating temperature, and contact time were studied to optimise the conditions for maximum removal of Pb(II) ions. On the basis of batch test results, optimal operating conditions were determined to be an initial pH of 5.5, an adsorbent dosage of 1.0 g, an initial Pb(II) concentration of 30 ppm, and a temperature of 30 degrees C. Experimental results showed that a contact time of 45 min was generally sufficient to achieve equilibrium. After backpropagation (BP) training combined with principal component analysis (PCA), the ANN model was able to predict adsorption efficiency with a tangent sigmoid transfer function (tansig) at hidden layer with 11 neurons and a linear transfer function (purelin) at output layer. The Levenberg-Marquardt algorithm (LMA) was found as the best of 11 BP algorithms with a minimum mean squared error (MSE) of 0.000227875. The linear regression between the network outputs and the corresponding targets were proven to be satisfactory with a correlation coefficient of about 0.936 for five model variables used in this study.
Patch testing with rubber series in Europe: a critical review and recommendation.
Warburton, Katharine L; Uter, Wolfgang; Geier, Johannes; Spiewak, Radoslaw; Mahler, Vera; Crépy, Marie-Noëlle; Schuttelaar, Marie Louise; Bauer, Andrea; Wilkinson, Mark
2017-04-01
Rubber additives constitute an important group of contact allergens, particularly in certain occupations. To collect information regarding the current practice of using a 'rubber series' in Europe, and discuss this against the background of evidence concerning the prevalence of allergy in order to derive a recommendation for a 'European rubber series'. The following were performed: (i) a survey targeting all members of the COST action 'StanDerm' consortium, (ii) analysis of rubber contact allergy data in the database of the European Surveillance System on Contact Allergies, and (iii) a literature review. Information from 13 countries was available, from one or several departments of dermatology, and occasionally occupational health. Apart from some substances tested only in single departments, a broad overlap regarding important allergens was evident, but considerable variation existed between departments. An up-to-date 'European rubber series' is recommended, with the exclusion of substances only of historical concern. A 'supplementary rubber series' containing allergens of less proven importance, requiring further analysis, is recommended for departments specializing in occupational contact allergy. These should be continually updated as new evidence emerges. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Application of principal component analysis for the optimisation of lead(II) biosorption.
Wajda, Łukasz; Duda-Chodak, Aleksandra; Tarko, Tomasz; Kamiński, Paweł
2017-10-03
Current study was focused on optimising lead(II) biosorption carried out by living cells of Arthrospira platensis using Principal Component Analysis. Various experimental conditions were considered: initial metal concentration (50 and 100 mg/l), solution pH (4.0, 4.5, 5.0, 5.5) and contact time (10, 20, 30, 40, 50 and 60 min) at constant rotary speed 200 rpm. It was found that when the biomass was separated from experimental solutions by the filtration, almost 50% of initial metal dose was removed by the filter paper. Moreover, pH was the most important parameter influencing examined processes. The Principal Component Analysis indicated that the most optimum conditions for lead(II) biosorption were metal initial concentration 100 mg/l, pH 4.5 and time 60 min. According to the analysis of the first component it might be stated that the lead(II) uptake increases in time. In overall, it was found to be useful for analysing data obtained in biosorption experiments and eliminating insignificant experimental conditions. Experimental data fitted Langmuir and Dubinin-Radushkevich models indicating that physical and chemical absorption take place at the same time. Further studies are necessary to verify how sorption-desorption cycles affect A. platensis cells.
Removal of zinc (II) ion from aqueous solution by adsorption onto activated palm midrib bio-sorbent
NASA Astrophysics Data System (ADS)
Mulana, F.; Mariana; Muslim, A.; Mohibah, M.; Halim, K. H. Ku
2018-03-01
In this paper, palm midrib that was activated with mixed citric acid and tartaric acid as biosorbent was used to remove Zn (II) ion from aqueous solution. The aim of this research is to activate palm midrib by using a mixed citric acid and tartaric acid and to determine adsorption capacity of activated palm midrib biosorbent on Zn (II) ion uptake from aqueous solution. The effect of several parameters such as contact time, initial Zn (II) ion concentration and activator concentration on the degree of Zn (II) ion removal was examined. Atomic Absorption Spectroscopy method was performed to determine adsorbed amount of Zn (II) ion into activated biosorbent. The result showed that the adsorption process was relatively not so fast and equilibrium was reached after contact time of 120 min. The adsorption capacity of biosorbent reached a maximum when the concentration of mixed citric acid and tartaric acid was 1.6 M. The optimum adsorption capacity was 5.72 mg/g. The result was obtained on initial Zn (II) ion concentration of 80 ppm for 120-min contact time. Langmuir isotherm was found as the best fit for the equilibrium data indicating homogeneous adsorption of metal ions onto the biosorbent surface.
Method of removing oxidized contaminants from water
Amonette, James E.; Fruchter, Jonathan S.; Gorby, Yuri A.; Cole, Charles R.; Cantrell, Kirk J.; Kaplan, Daniel I.
1998-01-01
The present invention is a method for removing oxidized contaminant(s) from water. More specifically, the invention has the steps of contacting water containing the oxidized contaminant(s) with a layered aluminosilicate having Fe(II). The aluminosilicate may contain naturally occurring Fe(II), or the Fe(II) may be produced by reducing Fe(III) that is initially present. Reduction may be either by exposure to a chemical or biological reductant. Contacting the water containing oxidized contaminant(s) may be by (1) injection of Fe(II)-containing layered aluminosilicate, via a well, into a saturated zone where it is likely to intercept the contaminated water; (2) injection of contaminated water into a vessel containing the Fe(II)-bearing layered aluminosilicate; and (3) first reducing Fe(III) in the layered aluminosilicate to Fe(II) by injection of a biological or chemical reductant, into an aquifer or vessel having sufficient Fe(III)-bearing aluminosilicate to produce the necessary Fe(II).
Method of removing oxidized contaminants from water
Amonette, J.E.; Fruchter, J.S.; Gorby, Y.A.; Cole, C.R.; Cantrell, K.J.; Kaplan, D.I.
1998-07-21
The present invention is a method for removing oxidized contaminant(s) from water. More specifically, the invention has the steps of contacting water containing the oxidized contaminant(s) with a layered aluminosilicate having Fe(II). The aluminosilicate may contain naturally occurring Fe(II), or the Fe(II) may be produced by reducing Fe(III) that is initially present. Reduction may be either by exposure to a chemical or biological reductant. Contacting the water containing oxidized contaminant(s) may be by (1) injection of Fe(II)-containing layered aluminosilicate, via a well, into a saturated zone where it is likely to intercept the contaminated water; (2) injection of contaminated water into a vessel containing the Fe(II)-bearing layered aluminosilicate; and (3) first reducing Fe(III) in the layered aluminosilicate to Fe(II) by injection of a biological or chemical reductant, into an aquifer or vessel having sufficient Fe(III)-bearing aluminosilicate to produce the necessary Fe(II). 8 figs.
RNA polymerase II conserved protein domains as platforms for protein-protein interactions
García-López, M Carmen
2011-01-01
RNA polymerase II establishes many protein-protein interactions with transcriptional regulators to coordinate gene expression, but little is known about protein domains involved in the contact with them. We use a new approach to look for conserved regions of the RNA pol II of S. cerevisiae located at the surface of the structure of the complex, hypothesizing that they might be involved in the interaction with transcriptional regulators. We defined five different conserved domains and demonstrate that all of them make contact with transcriptional regulators. PMID:21922063
Energy efficient industrialized housing research program
DOE Office of Scientific and Technical Information (OSTI.GOV)
Berg, R.; Brown, G.Z.; Finrow, J.
1989-01-01
This is the second volume of a two volume report on energy efficient industrialized housing. Volume II contains support documentation for Volume I. The following items are included: individual trip reports; software bibliography; industry contacts in the US, Denmark, and Japan; Cost comparison of industrialized housing in the US and Denmark; draft of the final report on the systems analysis for Fleetwood Mobile Home Manufacturers. (SM)
Akinci Cansunar, Hatice; Uysal, Tancan
2016-07-01
The aim of this study was to evaluate the clinical outcomes of three different Class II treatment modalities followed by fixed orthodontic therapy, using the American Board of Orthodontics Model Grading System (ABO-MGS). As a retrospective study, files of patients treated at postgraduate orthodontic clinics in different cities in Turkey was randomly selected. From 1684 posttreatment records, 669 patients were divided into three groups: 269 patients treated with extraction of two upper premolars, 198 patients treated with cervical headgear, and 202 patients treated with functional appliances. All the cases were evaluated by one researcher using ABO-MGS. The χ (2), Z test, and multivariate analysis of variance were used for statistical evaluation (p < 0.05). No significant differences were found among the groups in buccolingual inclination, overjet, occlusal relationship, and root angulation. However, there were significant differences in alignment, marginal ridge height, occlusal contact, interproximal contact measurements, and overall MGS average scores. The mean treatment time between the extraction and functional appliance groups was significantly different (p = 0.017). According to total ABO-MGS scores, headgear treatment had better results than functional appliances. The headgear group had better tooth alignment than the extraction group. Headgear treatment resulted in better occlusal contacts than the functional appliances and had lower average scores for interproximal contact measurements. Functional appliances had the worst average scores for marginal ridge height. Finally, the functional appliance group had the longest treatment times.
Analysis of the interaction of an electron beam with a solar cell. I. II
NASA Technical Reports Server (NTRS)
Von Roos, O.
1978-01-01
The short-circuit current generated by the electron beam of a scanning electron microscope when it impinges on the N-P junction of a solar cell is known to be dependent on the configuration used to investigate the cell's response, and the situation for one specific configuration is analyzed. This configuration is the case in which the highly collimated electron beam strikes the edge of a planar junction a variable distance away from the edge of the depletion layer. An earlier treatment is generalized to encompass the ohmic contact at the back surface. The analysis employing Fourier and Wiener-Hopf techniques shows that it is impractical to determine the bulk diffusion length of a solar cell by a SEM used in the studied configuration unless the ohmic contact is partially removed.
77 FR 71642 - New International Mail Contract
Federal Register 2010, 2011, 2012, 2013, 2014
2012-12-03
... electronically should contact the person identified in the FOR FURTHER INFORMATION CONTACT section by telephone for advice on filing alternatives. FOR FURTHER INFORMATION CONTACT: Stephen L. Sharfman, General Counsel, at 202-789-6820. SUPPLEMENTARY INFORMATION: Table of Contents I. Introduction II. Contents of...
Yi, Zhengji; Yao, Jun; Zhu, Mijia; Chen, Huilun; Wang, Fei; Liu, Xing
2016-01-01
The goal of this research is to investigate the feasibility of using activated coal-based activated carbon (CBAC) to adsorb Pb(II) from aqueous solutions through batch tests. Effects of contact time, pH, temperature and initial Pb(II) concentration on the Pb(II) adsorption were examined. The Pb(II) adsorption is strongly dependent on pH, but insensitive to temperature. The best pH for Pb(II) removal is in the range of 5.0-5.5 with more than 90 % of Pb(II) removed. The equilibrium time was found to be 60 min and the adsorption data followed the pseudo-second-order kinetics. Isotherm data followed Langmuir isotherm model with a maximum adsorption capacity of 162.33 mg/g. The adsorption was exothermic and spontaneous in nature. The Fourier transform infrared spectroscopy and scanning electron microscopy analysis suggested that CBAC possessed a porous structure and was rich in carboxyl and hydroxyl groups on its surface, which might play a major role in Pb(II) adsorption. These findings indicated that CBAC has great potential as an alternative adsorbent for Pb(II) removal.
MetaABC--an integrated metagenomics platform for data adjustment, binning and clustering.
Su, Chien-Hao; Hsu, Ming-Tsung; Wang, Tse-Yi; Chiang, Sufeng; Cheng, Jen-Hao; Weng, Francis C; Kao, Cheng-Yan; Wang, Daryi; Tsai, Huai-Kuang
2011-08-15
MetaABC is a metagenomic platform that integrates several binning tools coupled with methods for removing artifacts, analyzing unassigned reads and controlling sampling biases. It allows users to arrive at a better interpretation via series of distinct combinations of analysis tools. After execution, MetaABC provides outputs in various visual formats such as tables, pie and bar charts as well as clustering result diagrams. MetaABC source code and documentation are available at http://bits2.iis.sinica.edu.tw/MetaABC/ CONTACT: dywang@gate.sinica.edu.tw; hktsai@iis.sinica.edu.tw Supplementary data are available at Bioinformatics online.
NASA Technical Reports Server (NTRS)
Kennedy, Ronald; Padovan, Joe
1987-01-01
In a three-part series of papers, a generalized finite element solution strategy is developed to handle traveling load problems in rolling, moving and rotating structure. The main thrust of this section consists of the development of three-dimensional and shell type moving elements. In conjunction with this work, a compatible three-dimensional contact strategy is also developed. Based on these modeling capabilities, extensive analytical and experimental benchmarking is presented. Such testing includes traveling loads in rotating structure as well as low- and high-speed rolling contact involving standing wave-type response behavior. These point to the excellent modeling capabilities of moving element strategies.
Clinical relevance of positive patch test reactions to the 26 EU-labelled fragrances.
van Oosten, Eleonoor J; Schuttelaar, Marie-Louise A; Coenraads, Pieter Jan
2009-10-01
Fragrance mix I (FM I) and fragrance mix II (FM II) in the European baseline series are used as screening tools for fragrance contact allergy. In 2005 the European Union (EU) required labelling of 26 fragrances when present in cosmetic products. INCI nomenclature is obligatory for such labelling. To describe frequencies of contact allergy to these 26 fragrance substances, and to evaluate clinical relevance of these positive reactions. Three hundred and twenty patients with eczema suspected of being contact allergy to fragrances or cosmetics were patch tested with the EU-declared fragrance chemicals, FM I and FM II. There were 76 positive reactions in 33 patients. Most reactions were seen to [corrected] hydroxyisohexyl 3-cyclohexene carboxaldehyde in 3.1%, followed by Evernia furfuracea (2.5%) and cinnamyl alcohol (2.5%). Twelve reactions to FM I and II were not confirmed by separate ingredients. Clinical relevance of positive reactions to fragrances was certain in 20/33 (61%). 10.3% of the patients had positive patch tests in the EU-list. Hydroxyisohexyl 3-cyclohexene carboxaldehyde, a component of FM II, was the most frequent allergen, followed by Evernia furfuracea. Since Evernia furfuracea is not part of FM I or FM II, relevant reactions can be missed when only the European baseline series is used.
U.S. EPA, Pesticide Product Label, MEADOWS HOUSEHOLD CONTACT AND RESIDUAL SPRAY, 05/25/1990
2011-04-14
... tieU. fte.s IIId other inIIII1 lilted below. Apply sunlC" until wilt. R.,.II n needed. ... Itt ...., 11 Willi nil "- • lilt '"" IlirtCtIJ II ,.... II c ••• ell:lII 'IU ... _ flcllilill. ...
Biosorption characteristic of Alcaligenes sp. BAPb.1 for removal of lead(II) from aqueous solution.
Jin, Yu; Yu, Sumei; Teng, Chunying; Song, Tao; Dong, Liying; Liang, Jinsong; Bai, Xin; Xu, Xiuhong; Qu, Juanjuan
2017-06-01
In this study, strain BAPb.1 was isolated from lead mining area and used as an adsorbent to remove lead(II) ions from aqueous solution. The physicochemical characteristics, heavy metal resistance and antibiotic sensitivity of strain BAPb.1 were investigated. Biosorption capacity was evaluated by batch biosorption experiments, and isothermal characteristics were discussed. Atomic force microscopy (AFM), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX) and Fourier transform infrared spectrometry (FTIR) were conducted to explore the mechanism for lead(II) adsorption. Based on morphological and physiological characteristics as well as the phylogenetic analysis of 16S rDNA sequences, strain BAPb.1 was identified as a member of the genus Alcaligenes. It exhibited high resistances to multiple heavy metals such as lead(II), copper(II), zinc(II), nickel(II) and chromium(VI), and to antibiotics such as kanamycin, ampicillin, streptomycin, chloramphenicol, and tetracycline. The optimum conditions for maximum biosorption rate of 85.2% and maximum capacity of 56.8 mg g -1 were found at pH of 5, adsorbent dosage of 1.5 g L -1 (dry weight), initial lead(II) concentration of 100 mg L -1 , and contact time of 30 min at 30 °C. Biosorption isotherms were well fitted with Langmuir isotherm model. Mechanism analysis reveals that the lead(II) ions may exchange with sodium and potassium ions, and the hydroxyl, carbonyl and phosphate groups on the cell surface can chelate the lead(II) ions, therefore, surface adsorption play significant role in the biosorption process.
Jappe, U; Schnuch, A; Uter, W
2005-02-01
The role of contact allergy in rosacea has rarely been investigated. In this retrospective study, 361 out of 76,697 patients tested and documented by the Information Network of Departments of Dermatology between 1995 and 2002 had rosacea. Patch tests included standard series and constituents of cosmetics and topical medicaments. 118/361 had additionally been patch tested with their own cosmetics/medicaments. Positive reactions occurred to nickel (II) sulfate in 9.3%, fragrance mix in 8.8%, thimerosal in 6.9%, Myroxylon pereirae resin in 5.9%, potassium dichromate in 4.6% and propolis in 2.8%. Whereas rosacea patients had a significantly higher risk of contact allergy to propolis compared to the remaining patients, in an age- and sex-adjusted analysis, contact allergy to nickel was significantly less frequent in this group. For Lyral, the risk was elevated, albeit not significantly. Only 2/329 patients were positive to neomycin sulfate and 1/100 to gentamicin sulfate, among the panel of (topical) antibiotics tested. Among 118 patients tested with their own products, 3 were tested to metronidazole, 1 reacting positively. Irritant or doubtful patch test reactions were provoked by various substances (vehicles, oxidants and preservatives of various creams), which might also be clinically important, considering the heightened sensitivity of rosaceous skin.
NASA Astrophysics Data System (ADS)
Saputro, S.; Mahardiani, L.; Wulandari, D. A.
2018-03-01
This research aimed to know the usage of sawdust of teak wood and rice husk waste as Pb (II) ion adsorbents in simulated liquid waste, the combined optimum mass required adsorbent to adsorb Pb(II) ion, the sensitivity of the solid-phase spectrophotometry (sps) method in determining the decrease of Pb (II) metal ion levels in the μg/L level. This research was conducted by experimental method in laboratory. Adsorbents used in this study were charcoal of sawdust sawdust activated using 15% ZnCl2 solution and activated rice husk using 2 N NaOH solution. The adsorption processes of sawdust and rice husk with Pb(II) solution was done by variation of mass combination with a ratio of 1: 0; 0: 1; 1: 1; 1: 2; and 2: 1. Analysis of Pb(II) ion concentration using SPS and characterization of sawdust and rice husk adsorbent ads using FTIR. The results showed that activated charcoal from sawdust of teak wood and rice husks can be used as Pb (II) metal ion adsorbents with adsorption capacity of 0.86 μg/L, charcoal from sawdust of teak wood and rice husk adsorbent with a combination of optimum mass contact of sawdust and rice husk is 2:1 as much as 3 grams can adsorb 42.80 μg/L. Solid-phase spectophotometry is a sensitive method for analysis of concentration decreasing levels of Pb(II) ion, after it was absorbed by sawdust of teak wood and rice husk with high sensitivity and has the limit of detection (LOD) of 0.06 μg/L.
Sobhanardakani, Soheil; Zandipak, Raziyeh
2015-07-01
2,4-Dinitrophenylhydrazine immobilized on sodium dodecyl sulfate (SDS)-coated magnetite and was used for removal of Cd(II) and Ni(II) ions from aqueous solution. The prepared product was characterized by X-ray diffraction (XRD) analysis, Fourier transform infrared spectroscopy (FT-IR), and scanning electron microscopy (SEM). The size of the nanoparticles according to SEM was obtained around 20-35 nm. In batch tests, the effects of pH, contact time, initial metal concentration, and temperature were studied. The kinetic and equilibrium data were modeled with recently developed models. The adsorption kinetics and isotherms were well fitted by the fractal-like pseudo-second-order model and Langmuir-Freundlich model, respectively. Maximum adsorption capacity by this adsorbent is 255.1 mg g(-1) for Cd(II) ion and 319.6 mg g(-1) for Ni(II) ion at pH 7.0 and 25 °C. The method was successfully applied to the removal of metal cations in real samples (tap water, river water, and petrochemical wastewater).
Adsorption of Cd(II) Metal Ion on Adsorbent beads from Biomass Saccharomycess cereviceae - Chitosan
NASA Astrophysics Data System (ADS)
Hasri; Mudasir
2018-01-01
The adsorbent beads that was preparation from Saccharomycess cereviceae culture strain FN CC 3012 and shrimp shells waste and its application for adsorption of Cd (II) metal ion has been studied. The study start with combination of Saccharomycess cereviceae biomass to chitosan (Sc-Chi), contact time, pH of solution and initial concentration of cations. Total Cd(II) metal ion adsorbed was calculated from the difference of metal ion concentration before and after adsorption by AAS. The results showed that optimum condition for adsorption of Cd(II) ions by Sc-Chi beads was achieved with solution pH of 4, contact time of 60 minutes and initial concentration adsorption 100mg/L. The hydroxyl (-OH) and amino (-NH2) functional groups were believed to be responsible for the adsorption of Cd(II) ions.
Sheng, Guodong; Yang, Shitong; Sheng, Jiang; Hu, Jun; Tan, Xiaoli; Wang, Xiangke
2011-09-15
Sequestration of Ni(II) on diatomite as a function of time, pH, and temperature was investigated by batch, XPS, and EXAFS techniques. The ionic strength-dependent sorption at pH < 7.0 was consistent with outer-sphere surface complexation, while the ionic strength-independent sorption at pH = 7.0-8.6 was indicative of inner-sphere surface complexation. EXAFS results indicated that the adsorbed Ni(II) consisted of ∼6 O at R(Ni-O) ≈ 2.05 Å. EXAFS analysis from the second shell suggested that three phenomena occurred at the diatomite/water interface: (1) outer-sphere and/or inner-sphere complexation; (2) dissolution of Si which is the rate limiting step during Ni uptake; and (3) extensive growth of surface (co)precipitates. Under acidic conditions, outer-sphere complexation is the main mechanism controlling Ni uptake, which is in good agreement with the macroscopic results. At contact time of 1 h or 1 day or pH = 7.0-8.0, surface coprecipitates occur concurrently with inner-sphere complexes on diatomite surface, whereas at contact time of 1 month or pH = 10.0, surface (co)precipitates dominate Ni uptake. Furthermore, surface loading increases with temperature increasing, and surface coprecipitates become the dominant mechanism at elevated temperature. The results are important to understand Ni interaction with minerals at the solid-water interface, which is helpful to evaluate the mobility of Ni(II) in the natural environment.
Use of separate ZnTe interface layers to form ohmic contacts to p-CdTe films
Gessert, T.A.
1999-06-01
A method of is disclosed improving electrical contact to a thin film of a p-type tellurium-containing II-VI semiconductor comprising: depositing a first undoped layer of ZnTe on a thin film of p-type tellurium containing II-VI semiconductor with material properties selected to limit the formation of potential barriers at the interface between the p-CdTe and the undoped layer, to a thickness sufficient to control diffusion of the metallic-doped ZnTe into the p-type tellurium-containing II-VI semiconductor, but thin enough to minimize affects of series resistance; depositing a second heavy doped p-type ZnTe layer to the first layer using an appropriate dopant; and depositing an appropriate metal onto the outer-most surface of the doped ZnTe layer for connecting an external electrical conductor to an ohmic contact. 11 figs.
Use of separate ZnTe interface layers to form OHMIC contacts to p-CdTe films
Gessert, Timothy A.
1999-01-01
A method of improving electrical contact to a thin film of a p-type tellurium-containing II-VI semiconductor comprising: depositing a first undoped layer of ZnTe on a thin film of p-type tellurium containing II-VI semiconductor with material properties selected to limit the formation of potential barriers at the interface between the p-CdTe and the undoped layer, to a thickness sufficient to control diffusion of the metallic-doped ZnTe into the p-type tellurim-containing II-VI semiconductor, but thin enough to minimize affects of series resistance; depositing a second heavy doped p-type ZnTe layer to the first layer using an appropriate dopant; and depositing an appropriate metal onto the outer-most surface of the doped ZnTe layer for connecting an external electrical conductor to an ohmic contact.
[Fractographic analysis of clinically failed anterior all ceramic crowns].
DU, Qian; Zhou, Min-bo; Zhang, Xin-ping; Zhao, Ke
2012-04-01
To identify the site of crack initiation and propagation path of clinically failed all ceramic crowns by fractographic analysis. Three clinically failed anterior IPS Empress II crowns and two anterior In-Ceram alumina crowns were retrieved. Fracture surfaces were examined using both optical stereo and scanning electron microscopy. Fractographic theory and fracture mechanics principles were applied to disclose the damage characteristics and fracture mode. All the crowns failed by cohesive failure within the veneer on the labial surface. Critical crack originated at the incisal contact area and propagated gingivally. Porosity was found within the veneer because of slurry preparation and the sintering of veneer powder. Cohesive failure within the veneer is the main failure mode of all ceramic crown. Veneer becomes vulnerable when flaws are present. To reduce the chances of chipping, multi-point occlusal contacts are recommended, and layering and sintering technique of veneering layer should also be improved.
Abdel-Aty, Azza M; Ammar, Nabila S; Abdel Ghafar, Hany H; Ali, Rizka K
2013-07-01
The present work represents the biosorption of Cd(II) and Pb(II) from aqueous solution onto the biomass of the blue green alga Anabaena sphaerica as a function of pH, biosorbent dosage, contact time, and initial metal ion concentrations. Freundlich, Langmuir, and Dubinin-Radushkevich (D-R) models were applied to describe the biosorption isotherm of both metals by A. sphaerica biomass. The biosorption isotherms studies indicated that the biosorption of Cd(II) and Pb(II) follows the Langmuir and Freundlish models. The maximum biosorption capacities (qmax ) were 111.1 and 121.95 mg/g, respectively, at the optimum conditions for each metal. From the D-R isotherm model, the mean free energy was calculated to be 11.7 and 14.3 kJ/mol indicating that the biosorption mechanism of Cd(II) and Pb(II) by A. sphaerica was chemisorption. The FTIR analysis for surface function group of algal biomass revealed the existence of amino, carboxyl, hydroxyl, and carbonyl groups, which are responsible for the biosorption of Cd(II) and Pb(II). The results suggested that the biomass of A. sphaerica is an extremely efficient biosorbent for the removal of Cd(II) and Pb(II) from aqueous solutions.
Biosorption of cadmium and lead from aqueous solution by fresh water alga Anabaena sphaerica biomass
Abdel -Aty, Azza M.; Ammar, Nabila S.; Abdel Ghafar, Hany H.; Ali, Rizka K.
2012-01-01
The present work represents the biosorption of Cd(II) and Pb(II) from aqueous solution onto the biomass of the blue green alga Anabaena sphaerica as a function of pH, biosorbent dosage, contact time, and initial metal ion concentrations. Freundlich, Langmuir, and Dubinin–Radushkevich (D–R) models were applied to describe the biosorption isotherm of both metals by A. sphaerica biomass. The biosorption isotherms studies indicated that the biosorption of Cd(II) and Pb(II) follows the Langmuir and Freundlish models. The maximum biosorption capacities (qmax) were 111.1 and 121.95 mg/g, respectively, at the optimum conditions for each metal. From the D–R isotherm model, the mean free energy was calculated to be 11.7 and 14.3 kJ/mol indicating that the biosorption mechanism of Cd(II) and Pb(II) by A. sphaerica was chemisorption. The FTIR analysis for surface function group of algal biomass revealed the existence of amino, carboxyl, hydroxyl, and carbonyl groups, which are responsible for the biosorption of Cd(II) and Pb(II). The results suggested that the biomass of A. sphaerica is an extremely efficient biosorbent for the removal of Cd(II) and Pb(II) from aqueous solutions. PMID:25685442
Removal of Copper(II) Ions in Aqueous Solutions Using Tannin-Rich Plants as Natural Bio-Adsorbents
NASA Astrophysics Data System (ADS)
Paksamut, J.; Boonsong, P.
2018-03-01
In this study, the purpose of our interest is to investigatethe adsorption behavior of copper (II) ions in aqueous solution using some tannin-rich plants as natural bio-adsorbents such as mangosteen peels (Garciniamangostana L.), cassava leaves (Manihotesculenta Crantz) and Thai copper pod leaves (Sennasiamea (Lam.)) as powder form in different dosage of adsorbent plant materials.The adsorption capacities at different pH of solution and contact time were performed.All the experiments in this studywere chosen at room temperature by batch technique. From the experimental results showed that cassava leaves gave better adsorbent properties than mangosteen peels and Thai copper pod leaves. The increasing dosage of all adsorbents and contact time have been found to increase adsorption capacities. In this respect, the adsorption capacities depend crucially on the adsorbents and contact time. The optimum pH of copper (II) ions adsorption was pH4. According to this work, it was observed that bioadsorbent materials from tannin-rich plants could be used to remove copper (II) ions from aqueous solutions.
Saman, Norasikin; Johari, Khairiraihanna; Song, Shiow-Tien; Kong, Helen; Cheu, Siew-Chin; Mat, Hanapi
2017-03-01
An effective organoalkoxysilanes-grafted lignocellulosic waste biomass (OS-LWB) adsorbent aiming for high removal towards inorganic and organic mercury (Hg(II) and MeHg(II)) ions was prepared. Organoalkoxysilanes (OS) namely mercaptoproyltriethoxylsilane (MPTES), aminopropyltriethoxylsilane (APTES), aminoethylaminopropyltriethoxylsilane (AEPTES), bis(triethoxysilylpropyl) tetrasulfide (BTESPT), methacrylopropyltrimethoxylsilane (MPS) and ureidopropyltriethoxylsilane (URS) were grafted onto the LWB using the same conditions. The MPTES grafted lignocellulosic waste biomass (MPTES-LWB) showed the highest adsorption capacity towards both mercury ions. The adsorption behavior of inorganic and organic mercury ions (Hg(II) and MeHg(II)) in batch adsorption studies shows that it was independent with pH of the solutions and dependent on initial concentration, temperature and contact time. The maximum adsorption capacity of Hg(II) was greater than MeHg(II) which respectively followed the Temkin and Langmuir models. The kinetic data analysis showed that the adsorptions of Hg(II) and MeHg(II) onto MPTES-LWB were respectively controlled by the physical process of film diffusion and the chemical process of physisorption interactions. The overall mechanism of Hg(II) and MeHg(II) adsorption was a combination of diffusion and chemical interaction mechanisms. Regeneration results were very encouraging especially for the Hg(II); this therefore further demonstrated the potential application of organosilane-grafted lignocellulosic waste biomass as low-cost adsorbents for mercury removal process. Copyright © 2016 Elsevier Ltd. All rights reserved.
Klick, B; Nishiura, H; Leung, G M; Cowling, B J
2014-04-01
Both case-ascertained household studies, in which households are recruited after an 'index case' is identified, and household cohort studies, where a household is enrolled before the start of the epidemic, may be used to test and estimate the protective effect of interventions used to prevent influenza transmission. A simulation approach parameterized with empirical data from household studies was used to evaluate and compare the statistical power of four study designs: a cohort study with routine virological testing of household contacts of infected index case, a cohort study where only household contacts with acute respiratory illness (ARI) are sampled for virological testing, a case-ascertained study with routine virological testing of household contacts, and a case-ascertained study where only household contacts with ARI are sampled for virological testing. We found that a case-ascertained study with ARI-triggered testing would be the most powerful design while a cohort design only testing household contacts with ARI was the least powerful. Sensitivity analysis demonstrated that these conclusions varied by model parameters including the serial interval and the risk of influenza virus infection from outside the household.
Shrestha, Sohan; Son, Guntae; Lee, Seung Hwan; Lee, Tae Gwan
2013-08-01
The Zn (II) adsorption capacity of lignite and coconut shell-based activated carbon fiber (ACF) was evaluated as a function of initial Zn (II) concentration, temperature and contact time in batch adsorption process in this study. Adsorption uptake increased with initial Zn (II) concentration and temperature. Optimal contact time for the adsorption of Zn (II) ions onto lignite and coconut shell-based ACF was found to be 50 min. Removal percentage decreased from 88.0% to 78.54% with the increment in initial Zn (II) concentration from 5 to 50 mg L(-1). Equilibrium data fit well with Langmuir-I isotherm indicating homogeneous monolayer coverage of Zn (II) ions on the adsorbent surface. Maximum monolayer adsorption capacity of Zn (II) ions on ACF was found to be 9.43 mg g(-1). Surface morphology and functionality of ACF prior to and after adsorption were characterized by electron microscopy and infrared spectroscopy. Various thermodynamic parameters such as standard Gibbs free energy (ΔG°), standard enthalpy (ΔH°), and standard entropy (ΔS°) were evaluated. Copyright © 2013 Elsevier Ltd. All rights reserved.
Nelson, S W
2001-10-01
Recent histological evidence has documented that grafted palatal connective tissue is capable of forming a new attachment to previously exposed roots in the treatment of gingival recession. No clinical studies have tested the ability of connective tissue that has been implanted beneath the periosteum into periodontal osseous defects to reduce probing depth and increase clinical attachment levels. This study reports the long-term clinical effect of subperiosteal and intraosseous connective tissue grafts on deep periodontal pockets. Connective tissue (CT) grafts were placed in 32 periodontal pockets on 27 patients. Grafts were classified into 3 groups. Type I grafts had 50% or more vascular surface contact and were < or = 2.5 mm thick. Type II grafts had 50% or more contact but were > 2.5 mm thick, and Type III grafts had less than 50% vascular contact regardless of thickness. Twelve of 14 Type I sites, 9 of 15 Type II sites, and 3 of 3 Type III sites were analyzed 9 to 13 years following treatment. Clinical attachment level change differed significantly between the graft types on survivor teeth (P < 0.05): Type III had 2 mm loss (95% confidence interval [CI]: 0.4 to 3.6), while Type II and Type I grafts had a 2.7 mm gain (95% CI: 2.0 to 3.4) and 4.3 mm gain (95% CI: 3.3 to 5.2), respectively. Similar substantial differences were presented for changes in probing depth and recession. This long-term (9 to 13 years) retrospective case-series analysis suggests substantial improvements in periodontal clinical measures for Type I CT grafts in deep periodontal pockets. Randomized trials are required to evaluate this promising procedure.
Federal Register 2010, 2011, 2012, 2013, 2014
2012-08-08
... research will be conducted through a series of projects and tests throughout the decade. Contact involving... 2020 Research and Testing Project tests and design options for the 2020 Census. II. Method of... Alternative Contact Strategy Test is the first test to support this research. The Census Bureau will test...
NASA Astrophysics Data System (ADS)
Mahlooji, Niloofar; Behzad, Mahdi; Tarahhomi, Atekeh; Maroney, Michael; Rudbari, Hadi Amiri; Bruno, Giuseppe; Ghanbari, Bahram
2016-04-01
Two new heteronuclear Nickel(II)/Sodium(I) complexes of a side-off compartmental Schiff base ligand were synthesized and characterized by spectroscopic methods. Crystal structures of both of the complexes were also obtained. The Schiff base ligand was synthesized from the condensation of meso-1,2-diphenyl-1,2-ethylenediamine with 2-hydroxy-3-methoxybenzaldehyde. In both of the complexes the Ni(II) ion is coordinated to the inner N2O2 coordination sphere with square-planar geometry and the Na(I) ion is coordinated to the outer O2 O2‧ coordination sphere. In Complex (1) with general formula [Ni(L)Na(CH3OH)(ClO4)] the sodium ion is seven coordinated while in (2) with general formula [{Ni(L)Na(OH2)}2(μ-Ni(CN)4)] the sodium ion is six coordinated. Intermolecular interactions in two studied complexes were analyzed using 3D Hirshfeld surfaces and corresponding 2D fingerprint plots. This analysis showed that the H … H and C … H/H … C contacts for both structures (altogether 67.5% of total Hirshfeld surface area for (1) and 77.6% for (2)) and the O … H/H … O (24.2%) for (1) and the N … H/H … N (8.1%) contacts for (2) were the characteristic intermolecular contacts in the related crystal structures.
Performance of Spent Mushroom Farming Waste (SMFW) Activated Carbon for Ni (II) Removal
NASA Astrophysics Data System (ADS)
Desa, N. S. Md; Ghani, Z. Ab; Talib, S. Abdul; Tay, C. C.
2016-07-01
The feasibility of a low cost agricultural waste of spent mushroom farming waste (SMFW) activated carbon for Ni(II) removal was investigated. The batch adsorption experiments of adsorbent dosage, pH, contact time, metal concentration, and temperature were determined. The samples were shaken at 125 rpm, filtered and analyzed using ICP-OES. The fifty percent of Ni(II) removal was obtained at 0.63 g of adsorbent dosage, pH 5-6 (unadjusted), 60 min contact time, 50 mg/L Ni(II) concentration and 25 °C temperature. The evaluated SMFW activated carbon showed the highest performance on Ni(II) removal compared to commercial Amberlite IRC86 resin and zeolite NK3. The result indicated that SMFW activated carbon is a high potential cation exchange adsorbent and suitable for adsorption process for metal removal. The obtained results contribute toward application of developed SMFW activated carbon in industrial pilot study.
Structure of catabolite activator protein with cobalt(II) and sulfate
DOE Office of Scientific and Technical Information (OSTI.GOV)
Rao, Ramya R.; Lawson, Catherine L., E-mail: cathy.lawson@rutgers.edu
2014-04-15
The crystal structure of E. coli catabolite activator protein with bound cobalt(II) and sulfate ions at 1.97 Å resolution is reported. The crystal structure of cyclic AMP–catabolite activator protein (CAP) from Escherichia coli containing cobalt(II) chloride and ammonium sulfate is reported at 1.97 Å resolution. Each of the two CAP subunits in the asymmetric unit binds one cobalt(II) ion, in each case coordinated by N-terminal domain residues His19, His21 and Glu96 plus an additional acidic residue contributed via a crystal contact. The three identified N-terminal domain cobalt-binding residues are part of a region of CAP that is important for transcriptionmore » activation at class II CAP-dependent promoters. Sulfate anions mediate additional crystal lattice contacts and occupy sites corresponding to DNA backbone phosphate positions in CAP–DNA complex structures.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Goutet, Michèle, E-mail: michele.goutet@inrs.fr; Pépin, Elsa; Langonné, Isabelle
2012-04-15
Identification of allergenic chemicals is an important occupational safety issue. While several methods exist to identify contact sensitizers, there is currently no validated model to predict the potential of chemicals to act as respiratory sensitizers. Previously, we reported that cytometry analysis of the local immune responses induced in mice dermally exposed to the respiratory sensitizer trimellitic anhydride (TMA 10%) and contact sensitizer dinitrochlorobenzene (DNCB 1%) could identify divergent expression of several immune parameters. The present study confirms, first, that IgE-positive B cells, MHC class II molecules, interleukin (IL)-2, IL-4 and IL-4Rα can differentiate the allergic reactions caused by high dosesmore » of strong respiratory (TMA, phthalic anhydride and toluene diisocyanate) and contact sensitizers (DNCB, dinitrofluorobenzene and oxazolone). The second part of the study was designed to test the robustness of these markers when classing the weakly immunogenic chemicals most often encountered. Six respiratory allergens, including TMA (2.5%), five contact allergens, including DNCB (0.25%), and two irritants were compared at doses of equivalent immunogenicity. The results indicated that IL-4Rα and IL-2 can be reliably used to discriminate sensitizers. Respiratory sensitizers induced markedly higher IL-4Rα levels than contact allergens, while irritants had no effect on this parameter. Inversely, contact allergens tended to induce higher percentages of IL-2{sup +}CD8{sup +} cells than respiratory allergens. In contrast, the markers MHC-II, IgE and IL-4 were not able to classify chemicals with low immunogenic potential. In conclusion, IL-4Rα and IL-2 have the potential to be used in classifying a variety of chemical allergens. -- Highlights: ► Identification of chemical allergens is an important occupational safety issue. ► There is currently no model to predict the potential of chemicals to induce asthma. ► We analyze immune responses induced in mice by a variety of chemical sensitizers. ► IL-2 and IL-4R alpha show potential to discriminate between both types of allergens. ► This method could be applied to highly and weakly immunogenic chemicals.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mussotter, Franz, E-mail: franz.mussotter@bfr.bund
Allergic contact dermatitis is a widespread disease with high clinical relevance affecting approximately 20% of the general population. Typically, contact allergens are low molecular weight electrophilic compounds which can activate the Keap1/Nrf2 pathway. We performed a proteomics study to reveal possible biomarkers for dendritic cell (DC) activation by contact allergens and to further elucidate the role of Keap1/Nrf2 signaling in this process. We used bone marrow derived dendritic cells (BMDCs) of wild-type (nrf2{sup +/+}) and Nrf2 knockout (nrf2{sup −/−}) mice and studied their response against the model contact sensitizers 2,4-dinitrochlorobenzene (DNCB), cinnamaldehyde (CA) and nickel(II) sulfate by 2-dimensional polyacrylamide gelmore » electrophoresis (2D-PAGE) in combination with electrospray ionization tandem mass spectrometry (ESI-MS/MS). Sodium dodecyl sulfate (SDS, 100 μM) served as irritant control. While treatment with nickel(II) sulfate and SDS had only little effects, CA and DNCB led to significant changes in protein expression. We found 18 and 30 protein spots up-regulated in wild-type cells treated with 50 and 100 μM CA, respectively. For 5 and 10 μM DNCB, 32 and 37 spots were up-regulated, respectively. Almost all of these proteins were not differentially expressed in nrf2{sup −/−} BMDCs, indicating an Nrf2-dependent regulation. Among them proteins were detected which are involved in oxidative stress and heat shock responses, as well as in signal transduction or basic cellular pathways. The applied approach allowed us to differentiate between Nrf2-dependent and Nrf2-independent cellular biomarkers differentially regulated upon allergen-induced DC activation. The data presented might contribute to the further development of suitable in vitro testing methods for chemical-mediated sensitization. - Highlights: • Contact allergens induce proteins involved in DC maturation Nrf2-dependently. • Induction of these proteins points to a functional role of Nrf2 in DC maturation. • Evidence that metabolic reprogramming enables DC activation by contact allergens. • Identification of biomarker candidates for development of in vitro testing methods.« less
Iguchi, I; Kamiyama, K; Imamichi, M; Ohashi, T; He, J; Wang, X; Imanishi, J
1996-06-01
To establish a method for evaluation of less irritating contact lens materials by dynamic contact with cornea, we examined epithelial and endothelial cell injury to the porcine cornea caused by rotatory rubbing with four kinds of hard contact lenses (HCL). The HCLs used were (1) polymethylmethacrylate (PMMA) HCL, (2) gas-permeable HCL composed of a graft co-polymer of dextran derivative and methylmethacrylate (MMA) (Suncon Mild II(TM), 12 Dk), (3) gas-permeable HCL composed of a graft co-polymer of dextran derivative, a monomer containing silicone, a monomer containing fluorine and MMA (New Dx HCL-136, 32 Dk), and (4) gas-permeable HCL composed of a monomer containing silicone, a monomer containing fluorine and MMA(RGPL-A, 216 Dk). Using a specially designed apparatus, we produced a standardized injury to the epithelium or endothelium of porcine corneas by holding the HCL against the corneal surface while rotating the lens rapidly. After rotatory rubbing of the HCL on the epithelium, the degree of rose bengal staining of the epithelial cells, indicating degeneration of the cells and mucin detachment, were significantly different among these HCLs (New Dx HCL-136 < Suncon Mild II(TM), PPMA < RGPL-A), and the cell injury rates of the endothelium were also significantly different among them (Suncon Mild II(TM) < New Dx HCL-136, PMMA < RGPL-A). The water-wettability of HCLs was not directly correlated with cell injury rates on epithelial and endothelial cells. Both the New Dx HCL-136 and Suncon Mild II(TM), which have a common composition of graft co-polymer of dextran derivative, are less irritating to the epithelium and to the endothelium. Also a very few patients complaints regarding Suncon Mild II(TM) wearing in individuals with dry eyes have been reported. Therefore, we would expect that the New Dx HCL-136 should be satisfactory for wear by individuals with dry eyes.
Leprosy exposure, infection and disease: a 25-year surveillance study of leprosy patient contacts.
Sarno, Euzenir Nunes; Duppre, Nadia Cristina; Sales, Anna Maria; Hacker, Mariana Andréa; Nery, José Augusto; de Matos, Haroldo José
2012-12-01
Contact surveillance is a valuable strategy for controlling leprosy. A dynamic cohort study of leprosy contacts was initiated in 1987 at Oswaldo Cruz Foundation. The objective of this work was to review the data on the major risk factors leading up to the infectious stage of the disease, estimate incidence rates of leprosy in the cohort and characterise the risk factors for the disease among the contacts under surveillance. The incidence rate of leprosy among contacts of leprosy patients was estimated at 0.01694 cases per person-year in the first five years of follow-up. The following factors were associated with acquiring the disease: (i) not receiving the BCG vaccine, (ii) a negative Mitsuda reaction and (iii) contact with a patient with a multibacillary clinical form of leprosy. The contacts of index patients who had high bacilloscopic index scores > 1 were at especially high risk of infection. The following factors were associated with infection, which was defined as a seropositive reaction for anti-phenolic glicolipid-1 IgM: (i) young age (< 20 years), (ii) a low measured Mitsuda reaction (< 5 mm) and (iii) contact with an index patient who had a high bacilloscopic index. BCG vaccination and re-vaccination were shown to be protective among household contacts. The main conclusions of this study indicate an urgent need for additional leprosy control strategies in areas with a high incidence of the disease.
Toxic metals biosorption by Jatropha curcas deoiled cake: equilibrium and kinetic studies.
Rawat, Anand P; Rawat, Monica; Rai, J P N
2013-08-01
The equilibrium sorption of Cr(VI) and Cu(II) from aqueous solution using Jatropha curcas deoiled cake, has been studied with respect to adsorbent dosage, contact time, pH, and initial metal concentration in batch mode experiments. Removal of Cu(II) by deoiled cake was greater than that of Cr(VI). The adsorbent chemical characteristics, studied by Fourier transform-infrared analysis, suggested that the presence of Cr(VI) and Cu(II) in the biomass influenced the bands corresponding to hydroxyl and carboxyl groups. Desorption studies revealed that maximum metals recovery was achieved by HNO3 followed by CH3COOH and HCl. The Freundlich isotherm model showed good fit to the equilibrium adsorption data. The adsorption kinetics followed the pseudo-second-order model, which provided the best correlation for the biosorption process, and suggested that J. curcas deoiled cake can be used as an efficient biosorbent over other commonly used sorbents for decontamination of Cr(VI)- and Cu(II)-containing wastewater.
Bahar, Shahriyar; Es'haghi, Zarrin; Nezhadali, Azizollah; Banaei, Alireza; Bohlooli, Shahab
2017-04-15
In the present study, nano-sized titanium oxides were applied for preconcentration and determination of Pb(II) in aqueous samples using hollow fiber based solid-liquid phase microextraction (HF-SLPME) combined with flame atomic absorption spectrometry (FAAS). In this work, the nanoparticles dispersed in caprylic acid as an extraction solvent was placed into a polypropylene porous hollow fiber segment supported by capillary forces and sonification. This membrane was in direct contact with solutions containing Pb (II). The effect of experimental conditions on the extraction, such as pH, stirring rate, sample volume, and extraction time were optimized. Under the optimal conditions, the performance of the proposed method was investigated for the determination of Pb (II) in food and water samples. The method was linear in the range of 0.6-3000μgmL -1 . The relative standard deviations and relative recovery of Pb (II) was 4.9% and 99.3%, respectively (n=5). Copyright © 2016 Elsevier Ltd. All rights reserved.
Mitsunobu, Satoshi; Zhu, Ming; Takeichi, Yasuo; Ohigashi, Takuji; Suga, Hiroki; Jinno, Muneaki; Makita, Hiroko; Sakata, Masahiro; Ono, Kanta; Mase, Kazuhiko; Takahashi, Yoshio
2016-01-01
We herein investigated the mechanisms underlying the contact leaching process in pyrite bioleaching by Acidithiobacillus ferrooxidans using scanning transmission X-ray microscopy (STXM)-based C and Fe near edge X-ray absorption fine structure (NEXAFS) analyses. The C NEXAFS analysis directly showed that attached A. ferrooxidans produces polysaccharide-abundant extracellular polymeric substances (EPS) at the cell-pyrite interface. Furthermore, by combining the C and Fe NEXAFS results, we detected significant amounts of Fe(II), in addition to Fe(III), in the interfacial EPS at the cell-pyrite interface. A probable explanation for the Fe(II) in detected EPS is the leaching of Fe(II) from the pyrite. The detection of Fe(II) also indicates that Fe(III) resulting from pyrite oxidation may effectively function as an oxidizing agent for pyrite at the cell-pyrite interface. Thus, our results imply that a key role of Fe(III) in EPS, in addition to its previously described role in the electrostatic attachment of the cell to pyrite, is enhancing pyrite dissolution. PMID:26947441
Contact allergic gastritis: an underdiagnosed entity?
Pföhler, Claudia; Körner, Rebecca; Vogt, Thomas; Müller, Cornelia S L
2012-01-01
Only a few cases of contact allergic gastritis in patients with nickel allergy have been reported. We report a case of probable contact-allergic gastritis in a 46-year-old woman. Clinical examination revealed lichenoid mucosal lesions of the gums adjacent to bridges and crowns that had been implanted several weeks back. Since implantation, the patient had suffered from gastrointestinal complaints (including stomach pain). Gastroscopy showed eosinophilic gastritis. Patch testing done under the diagnosis of contact allergic stomatitis showed positive reactions to: gold sodium thiosulphate; manganese (II) chloride; nickel (II) sulphate; palladium chloride; vanadium (III) chloride and zirconium (IV) chloride. The crowns and bridge contained gold, palladium and zirconium chloride, hence they were replaced by titan-based dentition. Shortly after replacing the artificial dentition, all gastrointestinal symptoms resolved spontaneously without further treatment. Delayed-type allergy against the components of artificial dentition seemed to be the cause of gastritis. PMID:23192576
Christopher, Femina Carolin; Anbalagan, Saravanan; Kumar, Ponnusamy Senthil; Pannerselvam, Sundar Rajan; Vaidyanathan, Vinoth Kumar
2017-06-01
In this study, chitosan functionalised magnetic nano-particles (CMNP) was synthesised and utilised as an effective adsorbent for the removal of Pb(II) ions from aqueous solution. The experimental studies reveal that adsorbent material has finer adsorption capacity for the removal of heavy metal ions. Parameters affecting the adsorption of Pb(II) ions on CMNP, such as initial Pb(II) ion concentration, contact time, solution pH, adsorbent dosage and temperature were studied. The adsorption equilibrium study showed that present adsorption system followed a Freundlich isotherm model. The experimental kinetic studies on the adsorption of Pb(II) ions exhibited that present adsorption process best obeyed with pseudo-first order kinetics. The maximum monolayer adsorption capacity of CMNP for the removal of Pb(II) ions was found to be 498.6 mg g -1 . The characterisation of present adsorbent material was done by FTIR, energy disperse X-ray analysis and vibrating sample magnetometer studies. Thermodynamic parameters such as Gibbs free energy (Δ G °), enthalpy (Δ H °) and entropy (Δ S °) have declared that the adsorption process was feasible, exothermic and spontaneous in nature. Sticking probability reported that adsorption of Pb(II) ions on CMNP was favourable at lower temperature and sticking capacity of Pb(II) ions was very high.
NASA Astrophysics Data System (ADS)
Hemissi, Hanène; Fezai, Ramzi; Mezni, Ali; Besbes-Hentati, Salma; Rzaigui, Mohamed
2018-07-01
From the system metal-cyclam-condensed phosphate is isolated the first complex of {(H3O+)2[Cu(II)(μ-P4O12)(cyclam)]}n(1). This complex was characterized by X-ray diffraction (XRD), spectroscopy (diffuse reflectance, UV-Vis and FT-IR) and thermal analysis (DTA/TGA). The solved molecular structure of 1 revealed one rare 1D-anionic polymeric copper(II)-complex, {[Cu(II)(μ-P4O12)(cyclam)]2-}n, involving two distinct ring ligands (cyclam / cyclotetraphosphate), in which a new coordination mode of the P4 O124- was observed. The counterions (H3O+) ensure the connection between 1D-polymers by acting as donor in a strong "charge-assisted" hydrogen bonds with P4O12 rings leading to 2D-supramolecular frameworks arranged in -A-B-A- fashion. The 2D-supramolecular network is stabilized by O/N-H…O interactions whereas the van der Waals contacts play a key role in the consolidation of the 3D packing as verified by Hirshfeld surface analysis in combination with 2D fingerprint plots. The biochemical properties of 1 was also evaluated via DDPH, ABTS, hydroxyl radical scavengers and ferric reducing power (FRP) showing promising antioxidant activities which has been clarified by means of the cyclic voltammetric study.
Taghavi, Mahmoud; Zazouli, Mohammad Ali; Yousefi, Zabihollah; Akbari-adergani, Behrouz
2015-11-01
In this study, multi-walled carbon nanotubes were functionalized by L-cysteine to show the kinetic and isotherm modeling of Cd (II) ions onto L-cysteine functionalized multi-walled carbon nanotubes. The adsorption behavior of Cd (II) ion was studied by varying parameters including dose of L-MWCNTs, contact time, and cadmium concentration. Equilibrium adsorption isotherms and kinetics were also investigated based on Cd (II) adsorption tests. The results showed that an increase in contact time and adsorbent dosage resulted in increase of the adsorption rate. The optimum condition of the Cd (II) removal process was found at pH=7.0, 15 mg/L L-MWCNTs dosage, 6 mg/L cadmium concentration, and contact time of 60 min. The removal percent was equal to 89.56 at optimum condition. Langmuir and Freundlich models were employed to analyze the experimental data. The data showed well fitting with the Langmuir model (R2=0.994) with q max of 43.47 mg/g. Analyzing the kinetic data by the pseudo-first-order and pseudo-second-order equations revealed that the adsorption of cadmium using L-MWSNTs following the pseudo-second-order kinetic model with correlation coefficients (R2) equals to 0.998, 0.992, and 0.998 for 3, 6, and 9 mg/L Cd (II) concentrations, respectively. The experimental data fitted very well with the pseudo-second-order. Overall, treatment of polluted solution to Cd (II) by adsorption process using L-MWCNT can be considered as an effective technology.
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Predicting helix–helix interactions from residue contacts in membrane proteins
Lo, Allan; Chiu, Yi-Yuan; Rødland, Einar Andreas; Lyu, Ping-Chiang; Sung, Ting-Yi; Hsu, Wen-Lian
2009-01-01
Motivation: Helix–helix interactions play a critical role in the structure assembly, stability and function of membrane proteins. On the molecular level, the interactions are mediated by one or more residue contacts. Although previous studies focused on helix-packing patterns and sequence motifs, few of them developed methods specifically for contact prediction. Results: We present a new hierarchical framework for contact prediction, with an application in membrane proteins. The hierarchical scheme consists of two levels: in the first level, contact residues are predicted from the sequence and their pairing relationships are further predicted in the second level. Statistical analyses on contact propensities are combined with other sequence and structural information for training the support vector machine classifiers. Evaluated on 52 protein chains using leave-one-out cross validation (LOOCV) and an independent test set of 14 protein chains, the two-level approach consistently improves the conventional direct approach in prediction accuracy, with 80% reduction of input for prediction. Furthermore, the predicted contacts are then used to infer interactions between pairs of helices. When at least three predicted contacts are required for an inferred interaction, the accuracy, sensitivity and specificity are 56%, 40% and 89%, respectively. Our results demonstrate that a hierarchical framework can be applied to eliminate false positives (FP) while reducing computational complexity in predicting contacts. Together with the estimated contact propensities, this method can be used to gain insights into helix-packing in membrane proteins. Availability: http://bio-cluster.iis.sinica.edu.tw/TMhit/ Contact: tsung@iis.sinica.edu.tw Supplementary information:Supplementary data are available at Bioinformatics online. PMID:19244388
Engfeldt, Malin; Hagvall, Lina; Isaksson, Marléne; Matura, Mihály; Mowitz, Martin; Ryberg, Kristina; Stenberg, Berndt; Svedman, Cecilia; Bruze, Magnus
2017-01-01
In 2014, the fragrance hydroxyisohexyl 3-cyclohexene carboxaldehyde (HICC) was excluded from the Swedish baseline series. To study (i) whether fragrance mix (FM) II with 5% HICC detects more positive reactions than usual FM II with 2.5% HICC, and (ii) the reproducibility of patch testing with HICC. Two thousand one hundred and eighteen dermatitis patients at five Swedish dermatology departments were consecutively tested with FM II 14% pet., FM II 16.5% pet., and duplicate preparations of HICC 5% pet. Of the patients, 3.2% reacted to FM II 14%, and 1.5% reacted to HICC. Separate testing with HICC detected 0.3% reactions without concomitant reactivity to FM II. FM II with 5% HICC did not give rise to more irritant reactions or signs of active sensitization than FM II with 2.5% HICC. Patch testing with duplicate applications of HICC increased the overall prevalence of HICC contact allergy to 1.9%. FM II with 5% HICC does not detect more positive reactions than FM II with 2.5% HICC. Separate testing with HICC does not detect a sufficient proportion of patients who react only to HICC, without concomitant reactions to FM II, to warrant its inclusion in a baseline series. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Carol Ruiz, Antoni; Masip Utset, Josep; Ariza Solé, Albert
2017-03-01
The benefit of primary angioplasty may be reduced if there are delays to reperfusion. Identification of the variables associated with these delays could improve health care. Analysis of the Codi Infart registry of Catalonia and of the time to angioplasty depending on the place of first medical contact. In 3832 patients analyzed, first medical contact took place in primary care centers in 18% and in hospitals without a catheterization laboratory in 37%. Delays were longer in these 2 groups than in patients attended by the outpatient emergency medical system or by hospitals with a catheterization laboratory (P < .0001, results in median): first medical contact to reperfusion indication time was 42minutes in both (overall 35minutes); first medical contact to artery opening time was 131 and 143minutes, respectively (overall 121minutes); total ischemia time was 230 and 260minutes (overall 215minutes). First medical contact to artery opening time > 120minutes was strongly associated with first medical contact in a center without a catheterization laboratory (OR, 4.96; 95% confidence interval, 4.14-5.93), and other factors such as age, previous coronary surgery, first medical contact during evening hours, nondiagnostic electrocardiogram, and Killip class ≥ III. Mortality at 30 days and 1 year was 5.6% and 8.7% and was independently associated with age, longer delay to angioplasty, Killip class ≥ II, and first medical contact in a center with a catheterization laboratory. In more than 50% of patients requiring primary angioplasty, the first medical contact occurs in centers without a catheterization laboratory, which is an important predictor of delay from diagnosis to artery opening. Copyright © 2016 Sociedad Española de Cardiología. Published by Elsevier España, S.L.U. All rights reserved.
UV Chromospheric Activity in Cool, Short-Period Contact Binaries
NASA Technical Reports Server (NTRS)
Hrivnak, Bruce J.
2000-01-01
We have completed our analysis of the IUE spectra of the short-period contact binary OO Aql. OO Aql is a rare W UMa-type eclipsing binary in which the two solar-type stars may have only recently evolved into contact. The binary has an unusually high mass ratio (0.84), and a relatively long orbital period (0.506 d) for its spectral type (mid-G). Twelve ultraviolet spectra of OO Aql were obtained in 1988 with the IUE satellite, including a series of consecutive observations that cover nearly a complete orbital cycle. Chromospheric activity is studied by means of the Mg II h+k emission at 2800 A. The Mg II emission is found to vary, even when the emission is normalized to the adjacent continuum flux. This variation may be correlated with orbital phase in the 1988 observations. It also appears that the normalized Mg H emission varies with time, as seen in spectra obtained at two different epochs in 1988 and when compared with two spectra obtained several years earlier. The level of chromospheric activity in OO Aql is less than that of other W UMa-type binaries of similar colors, but this is attributed to its early stage of contact binary evolution. Ultraviolet light curves were composed from measurements of the ultraviolet continuum in the spectra. These were analyzed along with visible light curves of OO Aql to determine the system parameters. The large wavelength range in the light curves enabled a well-constrained fit to a cool spot in the system. A paper on these results is scheduled for publication in the February 2001 issue of the Astronomical Journal.
Gharieb, Rasha M A; Merwad, Abdallah M A; Saleh, Ayman A; El-Ghany, Amany M Abd
2018-06-12
Cryptosporidiosis is a parasitic zoonosis implicated in severe diarrhoea in pets and humans. This study aimed to determine the prevalence and genotypes of Cryptosporidium spp. in household dogs and in-contact children, and the risk factors associated with infection in children in Sharkia Province, Egypt. Fecal samples of 100 children (2-12 years old) and 50 dogs (3 months-1 year old) were randomly collected from both rural (children: n = 85, dogs: n = 40) and urban (children: n = 15, dogs: n = 10) households. Initial parasite detection was done by light microscopy, while, genotyping was based on molecular diagnostic assays. The overall prevalence of Cryptosporidium spp. infection in children was 35% using microscopy and 14% using nested polymerase chain reaction (PCR). In dogs, it was 34% using microscopy and 24% using nested PCR. Cryptosporidium spp. from children were identified as distinct genotypes, with the predominance of human genotype I (Cryptosporidium hominis) over the zoonotic genotype II (Cryptosporidium parvum). Moreover, only zoonotic genotype II (C. parvum) was identified in dog samples. The significant risk factors associated with the prevalence of Cryptosporidium infection in children were the presence of diarrheal episodes during time of survey, improper disposal of garbage, and dog feces and contact with other livestock (p ≤ 0.05). This study concluded that the existence of C. parvum in children and dogs residing the same households confirm the zoonotic transmission and its public health significance. Also, the study recommended the necessity of hygienic disposal of dog feces and preventing direct contact of dogs with other livestock.
NASA Astrophysics Data System (ADS)
R, Halimahtussaddiyah; Mashuni; Budiarni
2017-05-01
Southeast Sulawesi has a great stock of clay. It is probably to use as a source of adsorbent. The adsorbent capacity of clay can be largered with teratment using bread’s yeast as biomass. At this research, study of analysis adsorption of Mn(II) metal ion on clay immobilized Saccharomyces cerevisiae bread’s yeast biomass adsorbent has been conducted. The aims of this research were to determine the effects of contact time, pH and concentration of Mn(II) metal ion and to determine the adsorption capacity of clay immobilized S. cerevisiae biomass for adsorbtion of Mn(II) metal ion. Activated clay was synthesized by reaction of clay with KMnO4, H2SO4 and HCl. S. cerevisiae biomass was result by bread’s yeast mashed. Immobilization of S. cerevisiae biomass into clay was done by mixing of ratio of S. cerevisiae bread’s yeast biomass and clay equal to 1:3 (mass of biomassa : mass of clay). The adsorption capacity was determined by using Freundlich and Langmuir adsorption isoterms. The results of FTIR spectrums showed that the functional groups of clay immobilized S. cerevisiae biomass were Si-OH (wave number 1643 cm-1), Si-O-Si (wave number 1033 cm-1), N-H (wave number 2337 cm-1), O-H (wave number 3441cm-1), and C-H (wave number 2931 cm-1). The result of adsorption capacity from Mn(II) metal ion of contact time optimum 120 minutes, pH optimun at 7 and concentration optimum 50 mg/L were 1,816 mg/g; 0,509 mg/g and 2,624mg/g respectively. The adsorption capacity of Mn(II) metal ion with ratio 1:3 (biomass : clay) was 0,1045 mg/g. Type of isothermal adsorption followed the Freunlich adsorption.
Halogen bonds in some dihalogenated phenols: applications to crystal engineering.
Mukherjee, Arijit; Desiraju, Gautam R
2014-01-01
3,4-Dichlorophenol (1) crystallizes in the tetragonal space group I41/a with a short axis of 3.7926 (9) Å. The structure is unique in that both type I and type II Cl⋯Cl interactions are present, these contact types being distinguished by the angle ranges of the respective C-Cl⋯Cl angles. The present study shows that these two types of contacts are utterly different. The crystal structures of 4-bromo-3-chlorophenol (2) and 3-bromo-4-chlorophenol (3) have been determined. The crystal structure of (2) is isomorphous to that of (1) with the Br atom in the 4-position participating in a type II interaction. However, the monoclinic P21/c packing of compound (3) is different; while the structure still has O-H⋯O hydrogen bonds, the tetramer O-H⋯O synthon seen in (1) and (2) is not seen. Rather than a type I Br⋯Br interaction which would have been mandated if (3) were isomorphous to (1) and (2), Br forms a Br⋯O contact wherein its electrophilic character is clearly evident. Crystal structures of the related compounds 4-chloro-3-iodophenol (4) and 3,5-dibromophenol (5) were also determined. A computational survey of the structural landscape was undertaken for (1), (2) and (3), using a crystal structure prediction protocol in space groups P21/c and I41/a with the COMPASS26 force field. While both tetragonal and monoclinic structures are energetically reasonable for all compounds, the fact that (3) takes the latter structure indicates that Br prefers type II over type I contacts. In order to differentiate further between type I and type II halogen contacts, which being chemically distinct are expected to have different distance fall-off properties, a variable-temperature crystallography study was performed on compounds (1), (2) and (4). Length variations with temperature are greater for type II contacts compared with type I. The type II Br⋯Br interaction in (2) is stronger than the corresponding type II Cl⋯Cl interaction in (1), leading to elastic bending of the former upon application of mechanical stress, which contrasts with the plastic deformation of (1). The observation of elastic deformation in (2) is noteworthy; in that it finds an explanation based on the strengths of the respective halogen bonds, it could also be taken as a good starting model for future property design. Cl/Br isostructurality is studied with the Cambridge Structural Database and it is indicated that this isostructurality is based on shape and size similarity of Cl and Br, rather than arising from any chemical resemblance.
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Iguchi, I; Kamiyama, K; Ohashi, T; Wang, X; Imanishi, J
1996-11-01
To establish a new method for evaluation of contact lens materials, we studied the porcine endothelial cell injury caused by dynamic contact (rotatory rubbing) with three kinds of hard contact lenses (HCL). The HCLs used were 1) PMMA HCL, 2) oxygen-permeable HCL composed of a graft copolymer of dextran derivative and methylmethacrylate (MMA) (Suncon Mild II, 12 Dk), and 3) oxygen-permeable-HCL composed of a copolymer of a monomer containing silicone, a monomer containing fluorine, and MMA (RGPL-A, 216 Dk). Cell injury rates were significantly different among these HCLs (Suncon Mild II < PMMA < RGPL-A) although there were no differences in rotatory rubbing forces. The smoothness of HCL surface, the qualities of injured cell layers observed by scanning electron microscopy, and the water wettability of HCLs were not correlated with cell injury rate. These results suggest that physicochemical properties of materials other than rotatory rubbing force, smoothness, and water wettability were involved in the cell injury. Our evaluation method for biomaterials that injure the corneal endothelial cells by dynamic contact should be very useful for the development of biomaterials or medical devices, including HCLs and intracardiac and urethral catheters.
Job, J R; Fjeldsoe, B S; Eakin, E G; Reeves, M M
2018-04-01
Extended contact interventions provide support for continued weight management (weight loss/prevention of weight regain) following a weight loss intervention. Text messages offer a medium for delivery in a potentially cost-effective, broad-reach manner. This study aims to examine (i) the effectiveness of extended contact, text message interventions for adults in supporting weight management, and (ii) which intervention characteristics are common to those that are effective. A systematic database search (to 19 September 2016) was conducted. Meta-analyses were performed to quantify the average weight changes (kg) during the extended contact intervention, net of control (if a control group was present) and within-group. Seven studies were eligible for inclusion. The pooled effect of the extended contact intervention compared with control (n = 3 studies) was -0.82 kg (95% confidence interval -1.43, -0.21), while the pooled within-group weight loss (n = 6 studies) during the extended contact interventions was -2.16 kg (95% confidence interval -3.40, -0.91). Interventions considered 'effective' (n = 4) were more likely to be >12 weeks duration, compared with interventions considered 'ineffective' (n = 3). Evidence from the small number of studies reviewed suggests that extended contact, text message-delivered interventions are effective. Further research is required to elucidate effective intervention components and the longer-term impact on weight, diet and physical activity behaviour. © 2017 World Obesity Federation.
Friction Reduction through Ultrasonic Vibration Part 1: Modelling Intermittent Contact.
Vezzoli, Eric; Vidrih, Zlatko; Giamundo, Vincenzo; Lemaire-Semail, Betty; Giraud, Frederic; Rodic, Tomaz; Peric, Djordje; Adams, Michael
2017-01-01
Ultrasonic vibration is employed to modify the friction of a finger pad in way that induces haptic sensations. A combination of intermittent contact and squeeze film levitation has been previously proposed as the most probable mechanism. In this paper, in order to understand the underlying principles that govern friction modulation by intermittent contact, numerical models based on finite element (FE) analysis and also a spring-Coulombic slider are developed. The physical input parameters for the FE model are optimized by measuring the contact phase shift between a finger pad and a vibrating plate. The spring-slider model assists in the interpretation of the FE model and leads to the identification of a dimensionless group that allows the calculated coefficient of friction to be approximately superimposed onto an exponential function of the dimensionless group. Thus, it is possible to rationalize the computed relative reduction in friction being (i) dependent on the vibrational amplitude, frequency, and the intrinsic coefficient of friction of the device, and the reciprocal of the exploration velocity, and (ii) independent of the applied normal force, and the shear and extensional elastic moduli of the finger skin provided that intermittent contact is sufficiently well developed. Experimental validation of the modelling using real and artificial fingertips will be reported in part 2 of this work, which supports the current modelling.
EpiTools, A software suite for presurgical brain mapping in epilepsy: Intracerebral EEG.
Medina Villalon, S; Paz, R; Roehri, N; Lagarde, S; Pizzo, F; Colombet, B; Bartolomei, F; Carron, R; Bénar, C-G
2018-06-01
In pharmacoresistant epilepsy, exploration with depth electrodes can be needed to precisely define the epileptogenic zone. Accurate location of these electrodes is thus essential for the interpretation of Stereotaxic EEG (SEEG) signals. As SEEG analysis increasingly relies on signal processing, it is crucial to make a link between these results and patient's anatomy. Our aims were thus to develop a suite of software tools, called "EpiTools", able to i) precisely and automatically localize the position of each SEEG contact and ii) display the results of signal analysis in each patient's anatomy. The first tool, GARDEL (GUI for Automatic Registration and Depth Electrode Localization), is able to automatically localize SEEG contacts and to label each contact according to a pre-specified nomenclature (for instance that of FreeSurfer or MarsAtlas). The second tool, 3Dviewer, enables to visualize in the 3D anatomy of the patient the origin of signal processing results such as rate of biomarkers, connectivity graphs or Epileptogenicity Index. GARDEL was validated in 30 patients by clinicians and proved to be highly reliable to determine within the patient's individual anatomy the actual location of contacts. GARDEL is a fully automatic electrode localization tool needing limited user interaction (only for electrode naming or contact correction). The 3Dviewer is able to read signal processing results and to display them in link with patient's anatomy. EpiTools can help speeding up the interpretation of SEEG data and improving its precision. Copyright © 2018 Elsevier B.V. All rights reserved.
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Short-stack modeling of degradation in solid oxide fuel cells. Part I. Contact degradation
NASA Astrophysics Data System (ADS)
Gazzarri, J. I.; Kesler, O.
As the first part of a two paper series, we present a two-dimensional impedance model of a working solid oxide fuel cell (SOFC) to study the effect of contact degradation on the impedance spectrum for the purpose of non-invasive diagnosis. The two dimensional modeled geometry includes the ribbed interconnect, and is adequate to represent co- and counter-flow configurations. Simulated degradation modes include: cathode delamination, interconnect oxidation, and interconnect-cathode detachment. The simulations show differences in the way each degradation mode impacts the impedance spectrum shape, suggesting that identification is possible. In Part II, we present a sensitivity analysis of the results to input parameter variability that reveals strengths and limitations of the method, as well as describing possible interactions between input parameters and concurrent degradation modes.
The number of satellite cells in slow and fast fibres from human vastus lateralis muscle.
Kadi, Fawzi; Charifi, Nadia; Henriksson, Jan
2006-07-01
The aim of this investigation was to study the distribution of satellite cells in slow (type I fibres) and fast (type II fibres) fibres from human vastus lateralis muscle. This muscle is characterised by a mixed fibre type composition and is considered as the site of choice for biopsies in research work and for clinical diagnosis. Biopsy samples were obtained from five healthy young volunteers and a total of 1,747 type I fibres and 1,760 type II fibres were assessed. Satellite cells and fibre type composition were studied on serial muscle cross-sections stained with specific monoclonal antibodies. From a total of 218 satellite cells, 116 satellite cells were found in contact with type I fibres (53.6+/-8% of the satellite cells associated to type I fibres) and 102 satellite cells in contact with type II fibres (46.4+/-8% of the satellite cells associated to type II fibres). There was no significant difference (P=0.4) between the percentages of satellite cells in contact with type I and with type II fibres. Additionally, there was no relationship between the mean number of satellite cells per fibre and the mean cross-sectional area of muscle fibres. In conclusion, our results show that there is no fibre type-specific distribution of satellite cells in a human skeletal muscle with mixed fibre type composition.
Focal Contacts as Mechanosensors
Riveline, Daniel; Zamir, Eli; Balaban, Nathalie Q.; Schwarz, Ulrich S.; Ishizaki, Toshimasa; Narumiya, Shuh; Kam, Zvi; Geiger, Benjamin; Bershadsky, Alexander D.
2001-01-01
The transition of cell–matrix adhesions from the initial punctate focal complexes into the mature elongated form, known as focal contacts, requires GTPase Rho activity. In particular, activation of myosin II–driven contractility by a Rho target known as Rho-associated kinase (ROCK) was shown to be essential for focal contact formation. To dissect the mechanism of Rho-dependent induction of focal contacts and to elucidate the role of cell contractility, we applied mechanical force to vinculin-containing dot-like adhesions at the cell edge using a micropipette. Local centripetal pulling led to local assembly and elongation of these structures and to their development into streak-like focal contacts, as revealed by the dynamics of green fluorescent protein–tagged vinculin or paxillin and interference reflection microscopy. Inhibition of Rho activity by C3 transferase suppressed this force-induced focal contact formation. However, constitutively active mutants of another Rho target, the formin homology protein mDia1 (Watanabe, N., T. Kato, A. Fujita, T. Ishizaki, and S. Narumiya. 1999. Nat. Cell Biol. 1:136–143), were sufficient to restore force-induced focal contact formation in C3 transferase-treated cells. Force-induced formation of the focal contacts still occurred in cells subjected to myosin II and ROCK inhibition. Thus, as long as mDia1 is active, external tension force bypasses the requirement for ROCK-mediated myosin II contractility in the induction of focal contacts. Our experiments show that integrin-containing focal complexes behave as individual mechanosensors exhibiting directional assembly in response to local force. PMID:11402062
2014-01-01
Background Binding free energy and binding hot spots at protein-protein interfaces are two important research areas for understanding protein interactions. Computational methods have been developed previously for accurate prediction of binding free energy change upon mutation for interfacial residues. However, a large number of interrupted and unimportant atomic contacts are used in the training phase which caused accuracy loss. Results This work proposes a new method, βACV ASA , to predict the change of binding free energy after alanine mutations. βACV ASA integrates accessible surface area (ASA) and our newly defined β contacts together into an atomic contact vector (ACV). A β contact between two atoms is a direct contact without being interrupted by any other atom between them. A β contact’s potential contribution to protein binding is also supposed to be inversely proportional to its ASA to follow the water exclusion hypothesis of binding hot spots. Tested on a dataset of 396 alanine mutations, our method is found to be superior in classification performance to many other methods, including Robetta, FoldX, HotPOINT, an ACV method of β contacts without ASA integration, and ACV ASA methods (similar to βACV ASA but based on distance-cutoff contacts). Based on our data analysis and results, we can draw conclusions that: (i) our method is powerful in the prediction of binding free energy change after alanine mutation; (ii) β contacts are better than distance-cutoff contacts for modeling the well-organized protein-binding interfaces; (iii) β contacts usually are only a small fraction number of the distance-based contacts; and (iv) water exclusion is a necessary condition for a residue to become a binding hot spot. Conclusions βACV ASA is designed using the advantages of both β contacts and water exclusion. It is an excellent tool to predict binding free energy changes and binding hot spots after alanine mutation. PMID:24568581
Psychometric properties of the Beck Depression Inventory-II: a comprehensive review.
Wang, Yuan-Pang; Gorenstein, Clarice
2013-01-01
To review the psychometric properties of the Beck Depression Inventory-II (BDI-II) as a self-report measure of depression in a variety of settings and populations. Relevant studies of the BDI-II were retrieved through a search of electronic databases, a hand search, and contact with authors. Retained studies (k = 118) were allocated into three groups: non-clinical, psychiatric/institutionalized, and medical samples. The internal consistency was described as around 0.9 and the retest reliability ranged from 0.73 to 0.96. The correlation between BDI-II and the Beck Depression Inventory (BDI-I) was high and substantial overlap with measures of depression and anxiety was reported. The criterion-based validity showed good sensitivity and specificity for detecting depression in comparison to the adopted gold standard. However, the cutoff score to screen for depression varied according to the type of sample. Factor analysis showed a robust dimension of general depression composed by two constructs: cognitive-affective and somatic-vegetative. The BDI-II is a relevant psychometric instrument, showing high reliability, capacity to discriminate between depressed and non-depressed subjects, and improved concurrent, content, and structural validity. Based on available psychometric evidence, the BDI-II can be viewed as a cost-effective questionnaire for measuring the severity of depression, with broad applicability for research and clinical practice worldwide.
Deodorants are the leading cause of allergic contact dermatitis to fragrance ingredients.
Heisterberg, Maria V; Menné, Torkil; Andersen, Klaus E; Avnstorp, Christian; Kristensen, Berit; Kristensen, Ove; Kaaber, Knud; Laurberg, Grete; Henrik Nielsen, Niels; Sommerlund, Mette; Thormann, Jens; Veien, Niels K; Vissing, Susanne; Johansen, Jeanne D
2011-05-01
Fragrances frequently cause contact allergy, and cosmetic products are the main causes of fragrance contact allergy. As the various products have distinctive forms of application and composition of ingredients, some product groups are potentially more likely to play a part in allergic reactions than others. To determine which cosmetic product groups cause fragrance allergy among Danish eczema patients. This was a retrospective study based on data collected by members of the Danish Contact Dermatitis Group. Participants (N = 17,716) were consecutively patch tested with fragrance markers from the European baseline series (2005-2009). Of the participants, 10.1% had fragrance allergy, of which 42.1% was caused by a cosmetic product: deodorants accounted for 25%, and scented lotions 24.4%. A sex difference was apparent, as deodorants were significantly more likely to be listed as the cause of fragrance allergy in men (odds ratio 2.2) than in women. Correlation was observed between deodorants listed as the cause of allergy and allergy detected with fragrance mix II (FM II) and hydroxyisohexyl 3-cyclohexene carboxaldehyde. Deodorants were the leading causes of fragrance allergy, especially among men. Seemingly, deodorants have an 'unhealthy' composition of the fragrance chemicals present in FM II. © 2011 John Wiley & Sons A/S.
The impact of nanocontact on nanowire based nanoelectronics.
Lin, Yen-Fu; Jian, Wen-Bin
2008-10-01
Nanowire-based nanoelectronic devices will be innovative electronic building blocks from bottom up. The reduced nanocontact area of nanowire devices magnifies the contribution of contact electrical properties. Although a lot of two-contact-based ZnO nanoelectronics have been demonstrated, the electrical properties bringing either from the nanocontacts or from the nanowires have not been considered yet. High quality ZnO nanowires with a small deviation and an average diameter of 38 nm were synthesized to fabricate more than thirty nanowire devices. According to temperature behaviors of current-voltage curves and resistances, the devices could be grouped into three types. Type I devices expose thermally activated transport in ZnO nanowires and they could be considered as two Ohmic nanocontacts of the Ti electrode contacting directly on the nanowire. For those nanowire devices having a high resistance at room temperatures, they can be fitted accurately with the thermionic-emission theory and classified into type II and III devices according to their rectifying and symmetrical current-voltage behaviors. The type II device has only one deteriorated nanocontact and the other one Ohmic contact on single ZnO nanowire. An insulating oxide layer with thickness less than 20 nm should be introduced to describe electron hopping in the nanocontacts, so as to signalize one- and high-dimensional hopping conduction in type II and III devices.
NASA Astrophysics Data System (ADS)
Saputro, S.; Masykuri, M.; Mahardiani, L.; Kurniastuti, D.
2018-03-01
This research aim to examine the effect of the combination between corncobs and water hyacinth to adsorb lead (II), the most effective combination have determined by compared the ratio of corncobs adsorbent and water hyacinth to the increasing adsorption of the Pb(II), prove the effectiveness of the solid-phase spectrophotometry (sps) to determine the levels of Pb(II) as the result of the corncobs active charcoal adsorption and water hyacinth in the level of µg/L. The research method used is experimental method. The data collecting technique is carried out by several stages, which are carbonization using muffle furnace at a temperature of 350°C for 1.5 hours, activation of the corncobs charcoal and water hyacinth using HCl 1M and HCl 5M activator, contacting the adsorbent of corncobs active charcoal and water hyacinth with liquid waste simulation of Pb(II) using variation of corncobns and water hyacinth, 1:0; 0:1; 1:1; 2:1; 1:2, analysis of Pb(II) using an sps, characterization of corncobs active charcoal adsorbent and water hyacinth using FTIR. Research results show that the combined effect of activated charcoal corncobs and water hyacinth can increase the ability of the adsorbent to absorb Pb(II), the optimum adsorbent mass ratio of 1:1 with the absorption level of 90.33%, SPS is an effective method to analyze the decreasing level of Pb(II) as the adsorbtion result of the corncobs active charcoal and water hyacinth in the level of µg/L, with the limit of detection (LOD) of 0.06 µg/L.
1989-11-09
Approved for public release , distribution unlimited 13. SUPPLEMENTARY NOTES 14. ABSTRACT 15. SUBJECT TERMS 16. SECURITY CLASSIFICATION OF: 17...kilobasepairs KCl, potassium chloride LFA, lymphocyte function associated LPS, lipopolysaccharide LT, lymphotoxin LV, lentivirus J.LCi, microcurie ...process has also been studied extensively. IL 1 is released from macrophages following contact with helper T cells and one of its targets is the
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... person identified in the FOR FURTHER INFORMATION CONTACT section by telephone for advice on filing alternatives. FOR FURTHER INFORMATION CONTACT: Stephen L. Sharfman, General Counsel, at 202-789-6820. SUPPLEMENTARY INFORMATION: Table of Contents I. Introduction II. Contents of Filing III. Commission Action IV...
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Federal Register 2010, 2011, 2012, 2013, 2014
2012-12-20
... person identified in the FOR FURTHER INFORMATION CONTACT section by telephone for advice on filing alternatives. FOR FURTHER INFORMATION CONTACT: Stephen L. Sharfman, General Counsel, at 202-789-6820. SUPPLEMENTARY INFORMATION: Table of Contents I. Introduction II. Contents of Filing III. Commission Action IV...
Dinkloh, A; Worm, M; Geier, J; Schnuch, A; Wollenberg, A
2015-06-01
Ingredients of leave-on cosmetics and body care products may sensitize. However, not every case of cosmetic intolerance is due to contact sensitization. To describe the frequency of contact sensitization due to cosmetics in a large clinic population, and a possible particular allergen pattern. Retrospective analysis of data from the Information Network of Departments of Dermatology, 2006-2011. Of 69 487 patients tested, 'cosmetics, creams, sunscreens' was the only suspected allergen source category in 10 124 patients (14.6%). A final diagnosis 'allergic contact dermatitis' was stated in 2658 of these patients (26.3%).Compared to a control group, there were significantly more reactions to fragrance mixes I and II, balsam of Peru, methylchloroisothiazolinone/methylisothiazolinone (MCI/MI) and lanolin alcohols. No special pattern of fragrance sensitization could be identified. Among the preservatives, MI was by far the leading allergen, while sensitization to other widely used compounds like parabens or phenoxyethanol was rare. True allergic reactions to cosmetic ingredients are rarer than generally assumed. Limitation of exposure to MI in leave-on cosmetics and body care products is urgently needed. © 2014 European Academy of Dermatology and Venereology.
Estrada, Nicolas; Lizcano, Arcesio; Taboada, Alfredo
2010-07-01
This is the second of two papers investigating the mechanical response of cemented granular materials by means of contact dynamics simulations. In this paper, a two-dimensional polydisperse sample with high void ratio is sheared in a load-controlled simple shear numerical device until the stress state of the sample reaches the yield stress. We first study the stress transmission properties of the granular material in terms of the fabric of different subsets of contacts characterized by the magnitude of their normal forces. This analysis highlights the existence of a peculiar force carrying structure in the cemented material, which is reminiscent of the bimodal stress transmission reported for cohesionless granular media. Then, the evolution of contact forces and torques is investigated trying to identify the micromechanical conditions that trigger macroscopic yielding. It is shown that global failure can be associated to the apparition of a group of particles whose contacts fulfill at least one of the local rupture conditions. In particular, these particles form a large region that percolates through the sample at the moment of failure, evidencing the relationship between macroscopic yielding and the emergence of large-scale correlations in the system.
Le Poder, Sophie; Pham-Hung d'Alexandry d'Orangiani, Anne-Laure; Duarte, Lidia; Fournier, Annie; Horhogea, Cristina; Pinhas, Carine; Vabret, Astrid; Eloit, Marc
2013-12-01
Feline and canine coronaviruses (FCoV and CCoV, respectively) are common pathogens of cats and dogs sometimes leading to lethal infections named feline infectious peritonitis (FIP) and canine pantropic coronavirus infection. FCoV and CCoV are each subdivided into two serotypes, FCoV-I/II and CCoV-I/II. A phylogenetic relationship is evident between, on one hand, CCoV-I/FCoV-I, and on the other hand, CCoV-II/FCoV-II, suggesting that interspecies transmission can occur. The aim of the present study was to evaluate the prevalence of coronavirus (CoV)-infected cats according to their contact with dogs and to genetically analyse the CoV strains infecting cats. From 2003 to 2009, we collected 88 faecal samples from healthy cats and 11 ascitic fluids from FIP cats. We investigated the possible contact with dog in the household and collected dogs samples if appropriate. Out of 99 cat samples, 26 were coronavirus positive, with six cats living with at least one dog, thus showing that contact with dogs does not appear as a predisposing factor for cats CoV infections. Molecular and phylogenetic analyses of FCoV strains were conducted using partial N and S sequences. Six divergent strains were identified with the N gene clustering with CCoV-I whereas the 3' end of S was related to FCoV-I. Further analysis on those six samples was attempted by researching the presence of the ORF3 gene, the latter being peculiar to CCoV-I to date. We succeeded to amplify the ORF3 gene in five samples out of six. Thus, our data strongly suggest the circulation of atypical FCoV strains harbouring the CCoV-I ORF3 gene among cats. Moreover, the ORF3 genes recovered from the feline strains exhibited shared deletions, never described before, suggesting that these deletions could be critical in the adaptation of these strains to the feline host. Copyright © 2013 The Authors. Published by Elsevier B.V. All rights reserved.
Paramagnetic resonance studies of bistrispyrazolylborate cobalt(II) and related derivatives
NASA Astrophysics Data System (ADS)
Myers, William K.
Herein, a systematic frozen solution electron-nuclear double resonance (ENDOR) study of high-spin Co(II) complexes is reported to demonstrate the efficacy of methyl substitutions as a means of separating dipolar and contact coupling, and further, to increase the utility of high-spin Co(II) as a spectroscopic probe for the ubiquitous, but spectroscopically-silent Zn(II) metalloenzymes. High-spin (hs) Co(II) has been subject of paramagnetic resonance studies for over 50 years and has been used as a spectroscopic probe for Zn metalloenzymes for over 35 years. However, as will be seen, the inherent complexity of the electronic properties of the cobaltous ion remains to be exploited to offer a wealth of information on Zn(II) enzymatic environments. Specifically, ENDOR measurements on bistrispyrazolylborate cobalt(II) confirm the utility of the novel method of methyl substitution to differentiate dipolar and Fermi contact couplings. An extensive set of electron paramagnetic resonance (EPR) simulations were performed. Software was developed to implement an ENDOR control interface. Finally, proton relaxation measurements were made in the range of 12-42 MHz, which were accounted for with the large g-value anisotropy of the Co(II) compounds. Taken as a whole, these studies point to the rich complexity of the electronic structure of high-spin cobalt(II) and, when sufficiently well-characterized, the great utility it has as a surrogate of biological Zn(II).
NASA Technical Reports Server (NTRS)
1997-01-01
A 40 K Fastrac II duration test performed at Marshall Test Stand 116. The purpose of this test was to gauge the length of time between contact of TEA (Triethylenealuminum) and LOX (liquid oxygen) as an ignitor for the Fastrac engine.
Fragrance contact allergy: a 4-year retrospective study.
Cuesta, Laura; Silvestre, Juan Francisco; Toledo, Fernando; Lucas, Ana; Pérez-Crespo, María; Ballester, Irene
2010-08-01
Fragrance chemicals are the second most frequent cause of contact allergy. The mandatory labelling of 26 fragrance chemicals when present in cosmetics has facilitated management of patients allergic to fragrances. The study was aimed to define the characteristics of the population allergic to perfumes detected in our hospital district, to determine the usefulness of markers of fragrance allergy in the baseline GEIDAC series, and to describe the contribution made by the fragrance series to the data obtained with the baseline series. We performed a 4-year retrospective study of patients tested with the Spanish baseline series and/or fragrance series. There are four fragrance markers in the baseline series: fragrance mix I (FM I), Myroxylon pereirae, fragrance mix II (FM II), and hydroxyisohexyl 3-cyclohexene carboxaldehyde. A total of 1253 patients were patch tested, 117 (9.3%) of whom were positive to a fragrance marker. FM I and M. pereirae detected 92.5% of the cases of fragrance contact allergy. FM II and hydroxyisohexyl 3-cyclohexene carboxaldehyde detected 6 additional cases and provided further information in 8, enabling improved management. A fragrance series was tested in a selected group of 86 patients and positive results were obtained in 45.3%. Geraniol was the allergen most frequently found in the group of patients tested with the fragrance series. Classic markers detect the majority of cases of fragrance contact allergy. We recommend incorporating FM II in the Spanish baseline series, as in the European baseline series, and using a specific fragrance series to study patients allergic to a fragrance marker.
Lead and selenite adsorption at water–goethite interfaces from first principles
DOE Office of Scientific and Technical Information (OSTI.GOV)
Leung, Kevin; Criscenti, Louise J.
Here, the complexation of toxic and/or radioactive ions on to mineral surfaces is an important topic in geochemistry. We apply periodic-boundary-conditions density functional theory (DFT) molecular dynamics simulations to examine the coordination of Pb(II),more » $${\\rm SeO}_3^{2-}$$ , and their contact ion pairs to goethite (1 0 1) and (2 1 0) surfaces. The multitude of Pb(II) adsorption sites and possibility of Pb(II)-induced FeOH deprotonation make this a complex problem. At surface sites where Pb(II) is coordinated to three FeO and/or FeOH groups, and with judicious choices of FeOH surface group protonation states, the predicted Fe–Pb distances are in good agreement with EXAFS measurements. Trajectories where Pb(II) is in part coordinated to only two surface Fe–O groups exhibit larger fluctuations in Pb–O distances. Pb(II)/$${\\rm SeO}_3^{2-}$$ contact ion pairs are at least metastable on goethite (2 1 0) surfaces if the $${\\rm SeO}_3^{2-}$$ has a monodentate Se–O–Fe bond. Our DFT-based molecular dynamics calculations are a prerequisite for calculations of finite temperature equilibrium binding constants of Pb(II) and Pb(II)/$${\\rm SeO}_3^{2-}$$ ion pairs to goethite adsorption sites.« less
Lead and selenite adsorption at water–goethite interfaces from first principles
Leung, Kevin; Criscenti, Louise J.
2017-08-04
Here, the complexation of toxic and/or radioactive ions on to mineral surfaces is an important topic in geochemistry. We apply periodic-boundary-conditions density functional theory (DFT) molecular dynamics simulations to examine the coordination of Pb(II),more » $${\\rm SeO}_3^{2-}$$ , and their contact ion pairs to goethite (1 0 1) and (2 1 0) surfaces. The multitude of Pb(II) adsorption sites and possibility of Pb(II)-induced FeOH deprotonation make this a complex problem. At surface sites where Pb(II) is coordinated to three FeO and/or FeOH groups, and with judicious choices of FeOH surface group protonation states, the predicted Fe–Pb distances are in good agreement with EXAFS measurements. Trajectories where Pb(II) is in part coordinated to only two surface Fe–O groups exhibit larger fluctuations in Pb–O distances. Pb(II)/$${\\rm SeO}_3^{2-}$$ contact ion pairs are at least metastable on goethite (2 1 0) surfaces if the $${\\rm SeO}_3^{2-}$$ has a monodentate Se–O–Fe bond. Our DFT-based molecular dynamics calculations are a prerequisite for calculations of finite temperature equilibrium binding constants of Pb(II) and Pb(II)/$${\\rm SeO}_3^{2-}$$ ion pairs to goethite adsorption sites.« less
Federal Register 2010, 2011, 2012, 2013, 2014
2010-10-26
... study the feasibility of the 649 Water Street Project to be located on the Cobbosseecontee Stream, in.... Applicant Contact: Hoon Won, 275 River Road, P.O. Box 202, Woolwich, ME 04579; (203) 340-2517. FERC Contact...
[Contact allergic gastritis : Rare manifestation of a metal allergy].
Pföhler, C; Vogt, T; Müller, C S L
2016-05-01
Only a few cases of contact allergic gastritis in patients with nickel allergy have been reported in the literature. We report a case of probable contact-allergic gastritis in a 46-year-old woman. Clinical examination revealed lichenoid mucosal lesions of the gums adjacent to a bridge and crowns that had been implanted several weeks previously. Since implantation, the patient suffered from gastrointestinal complaints including stomach pain. Gastroscopy and histological investigation of stomach biopsies showed eosinophilic gastritis. Patch testing done under the diagnosis of contact allergic stomatitis showed positive reactions to gold sodium thiosulphate, manganese (II) chloride, nickel (II) sulphate, palladium chloride, vanadium (III) chloride, zirconium (IV) chloride, and fragrances. The crowns and the bridge contained gold, palladium, and zirconium, hence they were replaced by titan-based dentition. Shortly after replacing the artificial dentition, all gastrointestinal symptoms resolved spontaneously without further treatment. Delayed-type allergy to components in the artificial dentition seem to have caused the gastritis.
Fe-Si particles on the surface of blast furnace coke
NASA Astrophysics Data System (ADS)
Gornostayev, Stanislav S.; Heikkinen, Eetu-Pekka; Heino, Jyrki J.; Fabritius, Timo M. J.
2015-07-01
This study investigates the surface of unpolished samples of blast furnace (BF) coke drilled from the tuyere zone, which hosts Fe-Si particles (mostly Fe3Si) that vary in size, shape, depth of submersion (penetration) into the coke matrix, and contact features with the surface. Based on the shape of the particles and the extent of their contact with the coke matrix, they have been grouped into three major types: (I) sphere-like droplets with limited contact area, (II) semi-spheres with a larger contact area, and (III) irregular segregations with a spherical surface, which exhibit the largest contact area among the three types of particles. Considering the ratio between the height ( h) of the particles and half of their length at the surface level ( l) along the cross-section, these three types can be characterized as follows: (I) h > l, (II) h ≈ l, and (III) h < l. All the three types of particles can be found near each other. The shape and the extent of the contact depend on the degree of penetration of the material into the matrix, which is a function of the composition of the particles. Type (I) particles were initially saturated with Si at an earlier stage and, for that reason, they can react less with carbon in the coke matrix than type (II) and (III), thereby moving faster through the coke cone. Thermodynamic calculations have shown that the temperature interval of 1250-1300°C can be considered the starting point for Si entering into molten iron under quartz-dominated coke ash. Accordingly, the initial pick-up of Si by molten iron can be assumed to be mineral-related. In terms of BF practice, better conditions for sliding Fe-Si droplets through the coke cone are available when they come into contact with free SiO2 concentrated into small grains, and when the SiO2/ΣMe x O y mass ratio in the coke ash is high.
Enhanced Removal of Lead by Chemically and Biologically Treated Carbonaceous Materials
Mahmoud, Mohamed E.; Osman, Maher M.; Ahmed, Somia B.; Abdel-Fattah, Tarek M.
2012-01-01
Hybrid sorbents and biosorbents were synthesized via chemical and biological treatment of active carbon by simple and direct redox reaction followed by surface loading of baker's yeast. Surface functionality and morphology of chemically and biologically modified sorbents and biosorbents were studied by Fourier Transform Infrared analysis and scanning electron microscope imaging. Hybrid carbonaceous sorbents and biosorbents were characterized by excellent efficiency and superiority toward lead(II) sorption compared to blank active carbon providing a maximum sorption capacity of lead(II) ion as 500 μmol g−1. Sorption processes of lead(II) by these hybrid materials were investigated under the influence of several controlling parameters such as pH, contact time, mass of sorbent and biosorbent, lead(II) concentration, and foreign ions. Lead(II) sorption mechanisms were found to obey the Langmuir and BET isotherm models. The potential applications of chemically and biologically modified-active carbonaceous materials for removal and extraction of lead from real water matrices were also studied via a double-stage microcolumn technique. The results of this study were found to denote to superior recovery values of lead (95.0–99.0 ± 3.0–5.0%) by various carbonaceous-modified-bakers yeast biosorbents. PMID:22629157
El-Naggar, Mehrez E; Radwan, Emad K; El-Wakeel, Shaimaa T; Kafafy, Hany; Gad-Allah, Tarek A; El-Kalliny, Amer S; Shaheen, Tharwat I
2018-07-01
Recently, naturally occurring biopolymers have attracted the attention as potential adsorbents for the removal of water contaminants. In this work, we present the development of microcrystalline cellulose (MCC)-based nanogel grafted with acrylamide and acrylic acid in the presence of methylene bisacrylamide and potassium persulphate as a crosslinking agent and initiator, respectively. World-class facilities such as X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), surface analysis, field emission scanning electron microscopy (FE-SEM), high resolution transmission electron microscopy (HR-TEM) and zeta sizer were used to characterize the synthesized MCC based nanogel. The prepared nanogel was applied to remove reactive red 195 (RR195) dye and Cd (II) from aqueous medium at different operational conditions. The adsorption experiments showed that the feed concentration of monomers has a significant effect on the removal of RR195 which peaked (93% removal) after 10min of contact time at pH2 and a dose of 1.5g/L. On contrary, the feed concentration has insignificant effect on the removal of Cd (II) which peaked (97% removal) after 30min of contact time at pH6 and a dose of 0.5g/L. The adsorption equilibrium data of RR195 and Cd (II) was best described by Freundlich and Langmuir, respectively. Conclusively, the prepared MCC based nanogels were proved as promising adsorbents for the removal of organic pollutants as well as heavy metals. Copyright © 2018 Elsevier B.V. All rights reserved.
Sengor, Tomris; Aydin Kurna, Sevda; Ozbay, Nurver; Ertek, Semahat; Aki, Suat; Altun, Ahmet
2012-01-01
To evaluate ocular surface changes in long-term silicone hydrogel contact lens wearers. Thirty patients were included in this study. Twenty patients (40 eyes) using contact lenses constituted group 1 and 10 (20 eyes) volunteers constituted group 2. The duration of average contact lens usage was 7.74 ± 3.3 years. Ocular surface was evaluated by surface staining, tear film break-up time (TBUT), Schirmer I test, and conjunctival impression cytology with color-coded mapping technique and by the Ocular Surface Disease Index (OSDI). The mean break-up time was lower and staining scores were higher in group 1 (p<0.001) but Schirmer values were not significantly different from group 2 (p>0.05). The mean OSDI score was 34.59 ± 11.93 to 19.28 ± 6.7 in group 1 and 2. Increased metaplastic predominant changes of grade II and III were observed in the interpalpebral and perilimbal areas in group 1. Significant correlations were observed in TBUT, cornea staining, and grade II to grade III metaplasia ratios between duration of the lens usage and contact lens wear time in a day. Silicone hydrogel lenses produce significant changes on tear film and impression cytology of the ocular surface in long-term use.
Mohamad, Rapidah; Awang, Normah; Kamaludin, Nurul Farahana; Jotani, Mukesh M; Tiekink, Edward R T
2018-03-01
The crystal and mol-ecular structures of the two title organotin di-thio-carbamate compounds, [Sn(C 4 H 9 ) 2 (C 7 H 14 NO 2 S 2 ) 2 ], (I), and [Sn(C 6 H 5 ) 3 (C 5 H 10 NOS 2 )], (II), are described. Both structures feature asymmetrically bound di-thio-carbamate ligands leading to a skew-trapezoidal bipyramidal geometry for the metal atom in (I) and a distorted tetra-hedral geometry in (II). The complete mol-ecule of (I) is generated by a crystallographic twofold axis (Sn site symmetry 2). In the crystal of (I), mol-ecules self-assemble into a supra-molecular array parallel to (10-1) via methyl-ene-C-H⋯O(meth-oxy) inter-actions. In the crystal of (II), supra-molecular dimers are formed via pairs of weak phenyl-C-H⋯π(phen-yl) contacts. In each of (I) and (II), the specified assemblies connect into a three-dimensional architecture without directional inter-actions between them. Hirshfeld surface analyses confirm the importance of H⋯H contacts in the mol-ecular packing of each of (I) and (II), and in the case of (I), highlight the importance of short meth-oxy-H⋯H(but-yl) contacts between layers.
Concentrating Solar Power Projects - Palma del RÃo II | Concentrating
Capacity: Net: 50.0 MW Gross: 50.0 MW Status: Operational Start Year: 2010 Do you have more information ) Contact(s): Asun Padrós Company: Acciona EnergÃa Break Ground: October 2008 Start Production: December
Fragrance mix II in the baseline series contributes significantly to detection of fragrance allergy.
Heisterberg, Maria V; Andersen, Klaus E; Avnstorp, Christian; Kristensen, Berit; Kristensen, Ove; Kaaber, Knud; Laurberg, Grete; Menné, Torkil; Nielsen, Niels Henrik; Sommerlund, Mette; Thormann, Jens; Veien, Niels K; Vissing, Susanne; Johansen, Jeanne D
2010-11-01
Fragrance mix II (FM II) is a relatively new screening marker for fragrance contact allergy. It was introduced in the patch test baseline series in Denmark in 2005 and contains six different fragrance chemicals commonly present in cosmetic products and which are known allergens. To investigate the diagnostic contribution of including FM II in the baseline series by comparing it with other screening markers of fragrance allergy: fragrance mix I (FM I), Myroxylon pereirae and hydroxyisohexyl 3-cyclohexene carboxaldehyde (HICC). Retrospective study of 12 302 patients consecutively patch tested with FM II by members of the Danish Contact Dermatitis Group 2005-2008. FM II gave a positive patch test in 553 patients (4.5%), and in 72.2% of these patients the reaction was judged to be clinically relevant. FM II ranked second in detecting fragrance allergy, after FM I. If FM II had not been included as a screening marker in the baseline series, 15.6% (n = 202) of individuals with fragrance allergy would not have been identified by the other fragrance screening markers (FM I, M. pereirae or HICC). FM II contributes substantially to detecting fragrance allergy. It ranked second among the fragrance screening markers tested in the baseline series and detects individuals with an allergy who otherwise would not have been identified. © 2010 John Wiley & Sons A/S.
Stress Distribution and Damage Mode of Ceramic-Dentin Bilayer Systems
NASA Astrophysics Data System (ADS)
Kurtoglu, Cem; Demiroz, S. Suna; Mehmetov, Emirullah; Uysal, Hakan
The aim of this study was to evaluate the damage modes of ceramic systems bonded to dentin under Hertzian indentation. Single-cycle Hertzian contact test over 150-850 N load range was applied randomly to 210 ceramic-dentin bilayer disc specimens of zirconia or IPS Empress II -1 mm, -1.5 mm and of feldspathic porcelain -1 mm, -1.5 mm, -2 mm. Optical microscopy was employed for the identification of quasiplastic mode and radial cracks. Finite element analysis was used to analyze the stress distribution. Our results showed that the degree of damage in both modes evolved progressively and the origin changed with contact load. Stress location and value were consistent with the mechanical test results. It was concluded that microstructure and thickness of the material have a significant effect on the damage modes of ceramic layer systems.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Phuthong, Witchukorn; Huang, Zubin; Wittkopp, Tyler M.
To investigate the dynamics of photosynthetic pigment-protein complexes in vascular plants at high resolution in an aqueous environment, membrane-protruding oxygen-evolving complexes (OECs) associated with photosystem II (PSII) on spinach ( Spinacia oleracea) grana membranes were examined using contact mode atomic force microscopy. This study represents, to our knowledge, the first use of atomic force microscopy to distinguish the putative large extrinsic loop of Photosystem II CP47 reaction center protein (CP47) from the putative oxygen-evolving enhancer proteins 1, 2, and 3 (PsbO, PsbP, and PsbQ) and large extrinsic loop of Photosystem II CP43 reaction center protein (CP43) in the PSII-OEC extrinsicmore » domains of grana membranes under conditions resulting in the disordered arrangement of PSII-OEC particles. Moreover, we observed uncharacterized membrane particles that, based on their physical characteristics and electrophoretic analysis of the polypeptides associated with the grana samples, are hypothesized to be a domain of photosystem I that protrudes from the stromal face of single thylakoid bilayers. Furthermore, our results are interpreted in the context of the results of others that were obtained using cryo-electron microscopy (and single particle analysis), negative staining and freeze-fracture electron microscopy, as well as previous atomic force microscopy studies.« less
NASA Astrophysics Data System (ADS)
Rohmah, D. N.; Saputro, S.; Masykuri, M.; Mahardiani, L.
2018-03-01
The purpose of this research was to know the effect and determine the mass comparation which most effective combination between rice husk and coconut shell activated adsorbent to adsorb Pb (II) ion using SPS method. This research used experimental method. Technique to collecting this datas of this research is carried out by several stages, which are: (1) carbonization of rice husk and coconut shell adsorbent using muffle furnace at a temperature of 350°C for an hour; (2) activation of the rice husk and coconut shell adsorbent using NaOH 1N and ZnCl2 15% activator; (3) contacting the adsorbent of rice husk and coconut shell activated adsorbent with liquid waste simulation of Pb(II) using variation comparison of rice husk and coconut shell, 1:0; 0:1; 1:1; 2:1; 1:2; (4) analysis of Pb(II) using Solid-Phase Spectrophotometry (SPS); (5) characterization of combination rice husk and coconut shell activated adsorbent using FTIR. The result of this research show that the combined effect of combination rice husk and coconut shell activated adsorbent can increase the ability of the adsorbent to absorb Pb(II) ion then the optimum adsorbent mass ratio required for absorbing 20 mL of Pb(II) ion with a concentration of 49.99 µg/L is a ratio of 2:1 with the absorption level of 97,06%Solid-Phase Spectrophotometry (SPS) is an effective method in the level of µg/L, be marked with the Limit of Detection (LOD) of 0.03 µg/L.
NASA Astrophysics Data System (ADS)
Naeimi, Behrouz; Foroutan, Rauf; Ahmadi, Bahram; Sadeghzadeh, Farzaneh; Ramavandi, Bahman
2018-04-01
This study was designed to remove Pb(II) and Cd(II) from aqueous solution, shipyard wastewater, and sanitary landfill leachate using an alkaline-modified Rhizopus oryzae biomass. According to the Fourier transform infrared test, different functional groups like O–H, N–H, C=O, and P–O were detected in the bioadsorbent. The x-ray fluorescence (XRF) analysis showed that CaO, P2O3, and SO3 oxides have the highest content in the bioadsorbent. The surface area of modified Rhizopus oryzae was obtained as 20.32 m2 g‑1. The effect of initial pH, temperature, contact time, and bioadsorbent dose on the metals removal was discussed. At optimal conditions, maximum Pb(II) and Cd(II) removal was obtained 95.66% and 94.55%, respectively. Freundlich model was well- accurately described the equilibrium data. Among four studied models, the pseudo-second-order was better able to describe the kinetic behavior of the bioadsorption process. The amount of enthalpy, free energy of Gibbs, and entropy parameters indicated that the bioadsorption process of studied heavy metals is negative, exothermic, and spontaneous. The amount of heavy metals in a shipyard wastewater and sanitary landfill leachate was significantly decreased by using the developed bioadsorbent.
NASA Astrophysics Data System (ADS)
Purushothaman, Gayathri; Thiruvenkatam, Vijay
2017-11-01
Oximes are building block of organic synthesis and they have wide range applications in laboratories, industries, and pharmaceutical as antidotes. Herein we report the crystal structures of oxime derivative Beta-p-Dimethylaminodeoxybenzionoxime (I) and o-Chloro-p-dimethylaminodeoxybenzion (II) the precursor molecule of o-Chloro-p-dimethylaminodeoxybenzionoxime and their intermolecular interactions studies through Hirshfeld surface & 2D-fingerprint plot analysis along with PIXELC and DFT calculations. The packing arrangements in I and II are driven by Osbnd H⋯N and Osbnd H⋯C interactions respectively. The Osbnd H⋯N hydrogen bonding in I facilitates the formation of the dimer with the motif of R (22(6)), whereas in II absence of oxime moiety (dbnd NOH) restricts the dimer formation. The 2D-fingerprint plot shows the close contacts for the intermolecular interactions in I & II. The PIXELC calculation of II suggests Osbnd H⋯C contributes for intermolecular interaction that stabilizes the crystal packing with the total energy value of 60.4 kcal/mol. The DFT calculation using B3LYP with 6-311G (d, p) functional set for both the derivatives shows a small deviation in the benzene ring (I) and chlorobenzene ring (II) with the RMSD value of 0.5095 Å and 0.8472 Å respectively.
1979-12-01
Identification of Surface Treat- 4 ments of Ti 6-4 II Effect of Increasing Oxide Porosity on H20 Contact Angle on Titanium 6 Aluminum 4 Vanadium 26 viii SECTIONI...and a high SIMS yield. The lithium does not appear in the oxide formed on titanium by this mixture. Similarly porosity may be induced by anodization at...Porous Oxide (B). 25 TABLE II EFFECT OF INCREASING OXIDE POROSITY ON H2 0 CONTACT ANGLE ON TITANIUM 6 ALUMINUM 4 VANADIUM - I H 2 0Sample Electrolyte
Hull, C C; Crofts, N C
1996-03-01
The Beer-Lambert law has been used to determine the total attenuation coefficient, mu t, of three hard and three soft contact lens materials. The three hard contact lens materials were PMMA, Polycon II and Boston IV whereas the 3 soft materials were chosen with differing water contents of 38, 55 and 70%, respectively. The total attenuation coefficients of all six materials were obtained from measurements of the axial transmission at 632.8 nm of a series of plano powered lenses varying in axial thickness from 0.5 to 3.5 mm. The value of the total attenuation coefficient depends on both scattering and absorption and hence PMMA and Boston IV, which both incorporated a handling tint, showed significantly higher values (P < 0.0001) of mu t (0.562 +/- 0.010 mm-1 and 0.820 +/- 0.008 mm-1, respectively) than Polycon II (mu t = 0.025 +/- 0.005 mm-1). A comparison between Polycon II and the three hydrated soft contact lens materials showed a significant increase (P < 0.02) in the total attenuation coefficients for the 38% and 55% water content materials, and a weakly significant increase for the 70% water content soft lens material (P < 0.1). On the assumption that the absorption coefficients of these four materials are approximately constant, then this change would be due to an increase in the scattering coefficient of the material and could contribute to an increase in intraocular scatter. No significant difference (P > 0.5) was found between any of the hydrated soft contact lens materials tested.
The Influence of Multiple Host Contacts on the Acquisition and Transmission of Dengue-2 Virus
1993-01-01
5500 Stanoard Form 298 (Rev 2-89) PIs~~ bv AtI %t .34-| II Best Available Copy ABSTRACT Title of Dissertation: THE INFLUENCE OF MULTIPLE HOST CONTACTS...ABSTRACT Title of the Dissertaton: THE INFLUENCE OF MULTIPLE HOST CONTACTS ON THE ACQUISITION AND TRANSMISSION OF DENGUE-2 VIRUS BY A=DISAEX2 . John L...virus does not alter the feeding behavior of An. n•ngy~i. THE INFLUENCE OF MULTIPLE HOST CONTACTS ON THE ACQUISITION AND TRANSMISSION OF DENGUE-2 VIRUS BY
NASA Astrophysics Data System (ADS)
Soliman, Saied M.; El-Faham, Ayman
2018-07-01
Self assembly of Mn(II) perchlorate and bis(pyrazolo)-s-triazine pincer ligand (L) in methanol-water mixture afforded the homoleptic [MnL2](ClO4)2 complex (1) as plate colorless crystals. Following the crystallization process till the near dryness of the solution, we noted few needle like crystals of the heteroleptic [MnL(H2O)3](ClO4)2·H2O complex (2). Their molecular and supramolecular structures were analyzed using single crystal structure combined with Hirshfeld analysis. The packing of complexes 1 and 2 is dominated by weak Csbnd H⋯O and strong Osbnd H⋯O hydrogen bonds, respectively, as well as anion-π stacking interactions. Using Hirshfeld analysis, the percentages of the O⋯H intermolecular contacts are 32.7% and 36.8% for 1 and 2, respectively. The Mnsbnd N distances correlated well with the atoms in molecules (AIM) topological parameters. The amount of electron density transferred from the ligand units to the manganese centre are nearly the same (0.9 e) in both complexes.
NASA Astrophysics Data System (ADS)
Zaini, H.; Abubakar, S.; Rihayat, T.; Suryani, S.
2018-03-01
Removal of heavy metal content in wastewater has been largely done by various methods. One effective and efficient method is the adsorption method. This study aims to reduce manganese (II) content in wastewater based on column adsorption method using absorbent material from bagasse. The fixed variable consisted of 50 g adsorbent, 10 liter adsorbate volume, flow rate of 7 liters / min. Independent variable of particle size with variation 10 – 30 mesh and contact time with variation 0 - 240 min and respon variable concentration of adsorbate (ppm), pH and conductivity. The results showed that the adsorption process of manganese metal is influenced by particle size and contact time. The adsorption kinetics takes place according to pseudo-second order kinetics with an equilibrium adsorption capacity (qe: mg / g) for 10 mesh adsorbent particles: 0.8947; 20 mesh adsorbent particles: 0.4332 and 30 mesh adsorbent particles: 1.0161, respectively. Highest removal efficience for 10 mesh adsorbent particles: 49.22% on contact time 60 min; 20 mesh adsorbent particles: 35,25% on contact time 180 min and particle 30 mesh adsorbent particles: 51,95% on contact time 150 min.
Hortsch, Michael; Homer, Diahann; Malhotra, Jyoti Dhar; Chang, Sherry; Frankel, Jason; Jefford, Gregory; Dubreuil, Ronald R.
1998-01-01
Expression of the Drosophila cell adhesion molecule neuroglian in S2 cells leads to cell aggregation and the intracellular recruitment of ankyrin to cell contact sites. We localized the region of neuroglian that interacts with ankyrin and investigated the mechanism that limits this interaction to cell contact sites. Yeast two-hybrid analysis and expression of neuroglian deletion constructs in S2 cells identified a conserved 36-amino acid sequence that is required for ankyrin binding. Mutation of a conserved tyrosine residue within this region reduced ankyrin binding and extracellular adhesion. However, residual recruitment of ankyrin by this mutant neuroglian molecule was still limited to cell contacts, indicating that the lack of ankyrin binding at noncontact sites is not caused by tyrosine phosphorylation. A chimeric molecule, in which the extracellular domain of neuroglian was replaced with the corresponding domain from the adhesion molecule fasciclin II, also selectively recruited ankyrin to cell contacts. Thus, outside-in signaling by neuroglian in S2 cells depends on extracellular adhesion, but does not depend on any unique property of its extracellular domain. We propose that the recruitment of ankyrin to cell contact sites depends on a physical rearrangement of neuroglian in response to cell adhesion, and that ankyrin binding plays a reciprocal role in stabilizing the adhesive interaction. PMID:9660878
Hortsch, M; Homer, D; Malhotra, J D; Chang, S; Frankel, J; Jefford, G; Dubreuil, R R
1998-07-13
Expression of the Drosophila cell adhesion molecule neuroglian in S2 cells leads to cell aggregation and the intracellular recruitment of ankyrin to cell contact sites. We localized the region of neuroglian that interacts with ankyrin and investigated the mechanism that limits this interaction to cell contact sites. Yeast two-hybrid analysis and expression of neuroglian deletion constructs in S2 cells identified a conserved 36-amino acid sequence that is required for ankyrin binding. Mutation of a conserved tyrosine residue within this region reduced ankyrin binding and extracellular adhesion. However, residual recruitment of ankyrin by this mutant neuroglian molecule was still limited to cell contacts, indicating that the lack of ankyrin binding at noncontact sites is not caused by tyrosine phosphorylation. A chimeric molecule, in which the extracellular domain of neuroglian was replaced with the corresponding domain from the adhesion molecule fasciclin II, also selectively recruited ankyrin to cell contacts. Thus, outside-in signaling by neuroglian in S2 cells depends on extracellular adhesion, but does not depend on any unique property of its extracellular domain. We propose that the recruitment of ankyrin to cell contact sites depends on a physical rearrangement of neuroglian in response to cell adhesion, and that ankyrin binding plays a reciprocal role in stabilizing the adhesive interaction.
García-López, M. Carmen; Pelechano, Vicent; Mirón-García, M. Carmen; Garrido-Godino, Ana I.; García, Alicia; Calvo, Olga; Werner, Michel; Pérez-Ortín, José E.; Navarro, Francisco
2011-01-01
RNA polymerase (pol) II establishes many protein–protein interactions with transcriptional regulators to coordinate different steps of transcription. Although some of these interactions have been well described, little is known about the existence of RNA pol II regions involved in contact with transcriptional regulators. We hypothesize that conserved regions on the surface of RNA pol II contact transcriptional regulators. We identified such an RNA pol II conserved region that includes the majority of the “foot” domain and identified interactions of this region with Mvp1, a protein required for sorting proteins to the vacuole, and Spo14, a phospholipase D. Deletion of MVP1 and SPO14 affects the transcription of their target genes and increases phosphorylation of Ser5 in the carboxy-terminal domain (CTD). Genetic, phenotypic, and functional analyses point to a role for these proteins in transcriptional initiation and/or early elongation, consistent with their genetic interactions with CEG1, a guanylyltransferase subunit of the Saccharomyces cerevisiae capping enzyme. PMID:21954159
48 CFR 19.703 - Eligibility requirements for participating in the program.
Code of Federal Regulations, 2012 CFR
2012-10-01
... or Small Business Administration certification status of the ANC or Indian tribe. (ii) Where one or... accessing the Central Contractor Registration (CCR) database or by contacting the SBA. Options for contacting the SBA include— (i) HUBZone small business database search application Web page at http://dsbs...
48 CFR 19.703 - Eligibility requirements for participating in the program.
Code of Federal Regulations, 2011 CFR
2011-10-01
... or Small Business Administration certification status of the ANC or Indian tribe. (ii) Where one or... accessing the Central Contractor Registration (CCR) database or by contacting the SBA. Options for contacting the SBA include— (i) HUBZone small business database search application Web page at http://dsbs...
ZÁrate, Ana; Florez, July; Angulo, Edgardo; Varela-Prieto, Lourdes; Infante, Cherlys; Barrios, Fredy; Barraza, Beatriz; Gallardo, D I; Valdés, Jorge
2017-06-28
The use of microalgal biomass is an interesting technology for the removal of heavy metals from aqueous solutions owing to its high metal-binding capacity, but the interactions with bacteria as a strategy for the removal of toxic metals have been poorly studied. The goal of the current research was to investigate the potential of Burkholderia tropica co-immobilized with Chlorella sp. in polyurethane discs for the biosorption of Hg(II) from aqueous solutions and to evaluate the influence of different Hg(II) concentrations (0.041, 1.0, and 10 mg/l) and their exposure to different contact times corresponding to intervals of 1, 2, 4, 8, 16, and 32 h. As expected, microalgal bacterial biomass adhered and grew to form a biofilm on the support. The biosorption data followed pseudo-second-order kinetics, and the adsorption equilibrium was well described by either Langmuir or Freundlich adsorption isotherm, reaching equilibrium from 1 h. In both bacterial and microalgal immobilization systems in the coimmobilization of Chlorella sp. and B. tropica to different concentrations of Hg(II), the kinetics of biosorption of Hg(II) was significantly higher before 60 min of contact time. The highest percentage of biosorption of Hg(II) achieved in the co-immobilization system was 95% at pH 6.4, at 3.6 g of biosorbent, 30 ± 1°C, and a mercury concentration of 1 mg/l before 60 min of contact time. This study showed that co-immobilization with B. tropica has synergistic effects on biosorption of Hg(II) ions and merits consideration in the design of future strategies for the removal of toxic metals.
Li, Chengxian; Huang, Zhe; Huang, Bicheng; Liu, Changfeng; Li, Chengming; Huang, Yaqin
2014-01-01
Cr(VI) adsorption in a binary mixture Cr(VI)-Ni(II) using the hierarchical porous carbon prepared from pig bone (HPC) was investigated. The various factors affecting adsorption of Cr(VI) ions from aqueous solutions such as initial concentration, pH, temperature and contact time were analyzed. The results showed excellent efficiency of Cr(VI) adsorption by HPC. The kinetics and isotherms for Cr(VI) adsorption from a binary mixture Cr(VI)-Ni(II) by HPC were studied. The adsorption equilibrium described by the Langmuir isotherm model is better than that described by the Freundlich isotherm model for the binary mixture in this study. The maximum adsorption capacity was reliably found to be as high as 192.68 mg/g in the binary mixture at pH 2. On fitting the experimental data to both pseudo-first- and second-order equations, the regression analysis of the second-order equation gave a better R² value.
Ciavarella, Domenico; Lo Russo, Lucio; Nichelini, Jeffrey; Mastrovincenzo, Mario; Barbato, Ersilia; Laurenziello, Michele; Montaruli, Graziano; Lo Muzio, Lorenzo
2017-12-01
In the present paper, the authors analyze the effect of the "Swallowing Occlusal Contact Intercept Appliance" (SOCIA) in treatment of children with hyperdivergent Class II malocclusion. This functional appliance has no intra-oral anchorage, but induces a continuous periodontal, muscular, and articular stimulation. Twenty-six patients with hyperdivergent growth and class II malocclusion were selected and treated with SOCIA appliance. Cephalometric analysis was performed before treatment (T1) and immediately after the treatment (T2). After 24 months treatment authors observed a modification of maxillary growth with a reduction of the divergence with an increase of the posterior facial height, a modification of condylar inclination and forward position of the a hyoid. No modifications was observed about the ANB angle. After treatment the open bite was resolved with a reduction of the inclination of the upper incisors. SOCIA is a reliable functional appliance in growing age patients with a hyperdivergent pattern growth, anterior open bite and class II molar malocclusion.
Akar, Sibel Tunali; Arslan, Derya; Alp, Tugba
2012-08-15
The biosorption properties of APDC modified S. albus were tested in batch and column conditions. Effective experimental parameters such as pH, biosorbent dosage, contact time, temperature, initial lead(II) ion concentration, flow rate and bed height were investigated. The biosorption capacity of modified biosorbent was at maximum when lead(II) solution pH and biosorbent dosage were 5.5 and 2.0 g L(-1), respectively. The biosorption equilibrium was established in 20 min. Langmuir isotherm fitted well to the equilibrium data and kinetics is found to fit pseudo-second-order model. Increase in ionic strength of lead(II) solutions caused a slight decrease in the biosorption yield of APDC-modified biosorbent. Co-ions affected the biosorption performance of modified biomass up to maximum 20.81% reduction. Column biosorption of lead(II) showed higher biosorption yields at lower flow rates. Required time of breakthrough point was found to be 200 min. The recommended mechanism was found to depend mainly on electrostatic interaction, ion-exchange and complex formation. The ion-exchange mechanism for lead(II) biosorption onto the modified biosorbent is verified from the ionic strength effect and EDX analysis. Carbonyl, phosphate and CN groups on the modified surface of S. albus were found to responsible for complexation with lead(II). Copyright © 2012 Elsevier B.V. All rights reserved.
An Amino Acid Code for β-sheet Packing Structure
Joo, Hyun; Tsai, Jerry
2014-01-01
To understand the relationship between protein sequence and structure, this work extends the knob-socket model in an investigation of β-sheet packing. Over a comprehensive set of β-sheet folds, the contacts between residues were used to identify packing cliques: sets of residues that all contact each other. These packing cliques were then classified based on size and contact order. From this analysis, the 2 types of 4 residue packing cliques necessary to describe β-sheet packing were characterized. Both occur between 2 adjacent hydrogen bonded β-strands. First, defining the secondary structure packing within β-sheets, the combined socket or XY:HG pocket consists of 4 residues i,i+2 on one strand and j,j+2 on the other. Second, characterizing the tertiary packing between β-sheets, the knob-socket XY:H+B consists of a 3 residue XY:H socket (i,i+2 on one strand and j on the other) packed against a knob B residue (residue k distant in sequence). Depending on the packing depth of the knob B residue, 2 types of knob-sockets are found: side-chain and main-chain sockets. The amino acid composition of the pockets and knob-sockets reveal the sequence specificity of β-sheet packing. For β-sheet formation, the XY:HG pocket clearly shows sequence specificity of amino acids. For tertiary packing, the XY:H+B side-chain and main-chain sockets exhibit distinct amino acid preferences at each position. These relationships define an amino acid code for β-sheet structure and provide an intuitive topological mapping of β-sheet packing. PMID:24668690
75 FR 16204 - Region II Buffalo District Advisory Council; Public Meeting
Federal Register 2010, 2011, 2012, 2013, 2014
2010-03-31
... SMALL BUSINESS ADMINISTRATION Region II Buffalo District Advisory Council; Public Meeting AGENCY: U.S. Small Business Administration. ACTION: Notice of open Federal advisory committee meeting... roundtable discussion on small business issues. FOR FURTHER INFORMATION CONTACT: The meeting is open to the...
77 FR 20871 - Region II Buffalo District Advisory Council; Public Meeting
Federal Register 2010, 2011, 2012, 2013, 2014
2012-04-06
... SMALL BUSINESS ADMINISTRATION Region II Buffalo District Advisory Council; Public Meeting AGENCY: U.S. Small Business Administration. ACTION: Notice of open federal advisory committee meeting... business issues. FOR FURTHER INFORMATION CONTACT: The meeting is open to the public however advance notice...
76 FR 59480 - Region II Buffalo District Advisory Council; Public Meeting
Federal Register 2010, 2011, 2012, 2013, 2014
2011-09-26
... SMALL BUSINESS ADMINISTRATION Region II Buffalo District Advisory Council; Public Meeting AGENCY: U.S. Small Business Administration. ACTION: Notice of open Federal advisory committee meeting... discussion on small business issues. FOR FURTHER INFORMATION CONTACT: The meeting is open to the public...
Cholinergic neurons and fibres in the rat visual cortex.
Parnavelas, J G; Kelly, W; Franke, E; Eckenstein, F
1986-06-01
Choline acetyltransferase (ChAT), the acetylcholine synthesizing enzyme, was localized immunocytochemically in neurons and fibres in the rat visual cortex using a monoclonal antibody. ChAT-labelled cells were non-pyramidal neurons, primarily of the bipolar form, distributed in layers II through VI but concentrated in layers II & III. Their perikarya contained a large nucleus and a small amount of perinuclear cytoplasm. The somata and dendrites of all labelled cells received Gray's type I and type II synapses. ChAT-stained axons formed a dense and diffuse network throughout the visual cortex and particularly in layer V. Electron microscopy revealed that the great majority formed type II synaptic contacts with dendrites of various sizes, unlabelled non-pyramidal somata and, on a few occasions, with ChAT-labelled cells. However, a very small number of terminals appeared to form type I synaptic contacts. This study describes the morphological organization of the cholinergic system in the visual cortex, the function of which has been under extensive investigation.
Three-Dimensional Analysis of Enamel Crack Behavior Using Optical Coherence Tomography.
Segarra, M S; Shimada, Y; Sadr, A; Sumi, Y; Tagami, J
2017-03-01
The aim of this study was to nondestructively analyze enamel crack behavior on different areas of teeth using 3D swept source-optical coherence tomography (SS-OCT). Ten freshly extracted human teeth of each type on each arch ( n = 80 teeth) were inspected for enamel crack patterns on functional, contact and nonfunctional, or noncontact areas using 3D SS-OCT. The predominant crack pattern for each location on each specimen was noted and analyzed. The OCT observations were validated by direct observations of sectioned specimens under confocal laser scanning microscopy (CLSM). Cracks appeared as bright lines with SS-OCT, with 3 crack patterns identified: Type I - superficial horizontal cracks; Type II - vertically (occluso-gingival) oriented cracks; and Type III - hybrid or complicated cracks, a combination of a Type I and Type III cracks, which may or may not be confluent with each other. Type II cracks were predominant on noncontacting surfaces of incisors and canines and nonfunctional cusps of posterior teeth. Type I and III cracks were predominant on the contacting surfaces of incisors, cusps of canines, and functional cusps of posterior teeth. Cracks originating from the dental-enamel junction and enamel tufts, crack deflections, and the initiation of new cracks within the enamel (internal cracks) were observed as bright areas. CLSM observations corroborated the SS-OCT findings. We found that crack pattern, tooth type, and the location of the crack on the tooth exhibited a strong correlation. We show that the use of 3D SS-OCT permits for the nondestructive 3D imaging and analysis of enamel crack behavior in whole human teeth in vitro. 3D SS-OCT possesses potential for use in clinical studies for the analysis of enamel crack behavior.
The Role of Angiotensin II/AT1 Receptor Signaling in Regulating Retinal Microglial Activation.
Phipps, Joanna A; Vessey, Kirstan A; Brandli, Alice; Nag, Nupur; Tran, Mai X; Jobling, Andrew I; Fletcher, Erica L
2018-01-01
This study explored whether the proangiogenic factor Angiotensin II (AngII) had a direct effect on the activation state of microglia via the Angiotensin type 1 receptor (AT1-R). Microglial dynamic activity was investigated in live retinal flatmounts from adult Cx3Cr1+/GFP mice under control, AngII (5 μM) or AngII (5 μM) + candesartan (0.227 μM) conditions. The effects of intravitreal administration of AngII (10 mM) were also investigated at 24 hours, with retinae processed for immunocytochemistry, flow cytometry, or inflammatory quantitative PCR arrays. We found FACS isolated retinal microglia expressed AT1-R. In retinal flatmounts, microglia showed characteristic movement of processes under control conditions. Perfusion of AngII induced an immediate change in process length (-42%, P < 0.05) and activation state of microglia that was ameliorated by AT1-R blockade, suggesting a direct effect of AngII on microglia via the AT1-R. Intravitreal injection of AngII induced microglial activation after 24 hours, which was characterized by increased soma size (23%, P < 0.001) and decreased process length (20%, P < 0.05). Further analysis indicated a significant decrease in the number of microglial contacts with retinal neurons (saline 15.6 ± 2.31 versus AngII 7.8 ± 1.06, P < 0.05). Retinal cytokine and chemokine expression was modulated, indicative of an inflammatory retinal phenotype. We show that retinal microglia express AT1-R and their activation state is significantly altered by the angiogenic factor, AngII. Specifically, AngII may directly activate AT1-Rs on microglia and contribute to retinal inflammation. This may have implications for diseases like diabetic retinopathy where increases in AngII and inflammation have been shown to play an important role.
NASA Astrophysics Data System (ADS)
Purwanto, Agung; Yusmaniar, Ferdiani, Fatmawati; Damayanti, Rachma
2017-03-01
Silica gel modified APTS was synthesized from silica gel which was obtained from corn cobs via sol-gel process. Silica gel was synthesized from corn cobs and then chemically modified with silane coupling agent which has an amine group (NH2). This process resulting modified silica gel 3-aminopropyltriethoxysilane (APTS). Characterization of silica gel modified APTS by SEM-EDX showed that the size of the particles of silica gel modified APTS was 20µm with mass percentage of individual elements were nitrogen (N) 15.56%, silicon (Si) 50.69% and oxygen (O) 33.75%. In addition, silica gel modified APTS also showed absorption bands of functional groups silanol (Si-OH), siloxane (Si-O-Si), and an aliphatic chain (-CH2-), as well as amine (NH2) from FTIR spectra. Based on the characterization of XRD, silica gel 2θ of 21.094° and 21.32° respectively. It indicated that both material were amorphous. Determination of optimum pH and contact time on adsorption of silica gel 3-aminopropyltriethoxysilane (APTS) against Cu(II). The optimum pH and contact time was measured by using AAS. Optimum pH of adsorption silica gel modified APTS against metal Cu(II) could be obtained at pH 6 while optimum contact time was at 30 minutes, with the process of adsorption metal Cu(II) occured based on the model Freundlich isotherm.
21 CFR 886.5928 - Soft (hydrophilic) contact lens care products.
Code of Federal Regulations, 2010 CFR
2010-04-01
... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Soft (hydrophilic) contact lens care products. 886.5928 Section 886.5928 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... means of heat. (b) Classification. Class II (Special Controls) Guidance Document: “Guidance for Industry...
30 CFR 1204.205 - How do I obtain accounting and auditing relief?
Code of Federal Regulations, 2012 CFR
2012-07-01
... code, address, phone number, and contact name; and (ii) The specific ONRR lease number and agreement number, if applicable. (2) You may file a single notification for multiple marginal properties. (b) To... request must contain: (i) Your company name, ONRR-assigned payor code, address, phone number, and contact...
30 CFR 1204.205 - How do I obtain accounting and auditing relief?
Code of Federal Regulations, 2014 CFR
2014-07-01
... code, address, phone number, and contact name; and (ii) The specific ONRR lease number and agreement number, if applicable. (2) You may file a single notification for multiple marginal properties. (b) To... request must contain: (i) Your company name, ONRR-assigned payor code, address, phone number, and contact...
30 CFR 1204.205 - How do I obtain accounting and auditing relief?
Code of Federal Regulations, 2013 CFR
2013-07-01
... code, address, phone number, and contact name; and (ii) The specific ONRR lease number and agreement number, if applicable. (2) You may file a single notification for multiple marginal properties. (b) To... request must contain: (i) Your company name, ONRR-assigned payor code, address, phone number, and contact...
14 CFR 23.479 - Level landing conditions.
Code of Federal Regulations, 2010 CFR
2010-01-01
... attitudes: (1) For airplanes with tail wheels, a normal level flight attitude. (2) For airplanes with nose wheels, attitudes in which— (i) The nose and main wheels contact the ground simultaneously; and (ii) The main wheels contact the ground and the nose wheel is just clear of the ground. The attitude used in...
Process for the extraction of technetium from uranium
Gong, Cynthia-May S.; Poineau, Frederic; Czerwinski, Kenneth R.
2010-12-21
A spent fuel reprocessing method contacts an aqueous solution containing Technetium(V) and uranyl with an acidic solution comprising hydroxylamine hydrochloride or acetohydroxamic acid to reduce Tc(V) to Tc(II, and then extracts the uranyl with an organic phase, leaving technetium(II) in aqueous solution.
77 FR 60625 - Minimum Internal Control Standards for Class II Gaming
Federal Register 2010, 2011, 2012, 2013, 2014
2012-10-04
...-37 Minimum Internal Control Standards for Class II Gaming AGENCY: National Indian Gaming Commission... Internal Control Standards that were published on September 21, 2012. DATES: The effective date [email protected] . FOR FURTHER INFORMATION CONTACT: Jennifer Ward, Attorney, NIGC Office of General Counsel, at...
42 CFR 422.506 - Nonrenewal of contract.
Code of Federal Regulations, 2012 CFR
2012-10-01
... effective. The MA organization must also provide information about alternative enrollment options by doing... contact to learn about their enrollment options. (3) CMS may accept a nonrenewal notice submitted after... with paragraph (a)(2)(ii) of this section; and (ii) Acceptance is not inconsistent with the effective...
42 CFR 422.506 - Nonrenewal of contract.
Code of Federal Regulations, 2013 CFR
2013-10-01
... effective. The MA organization must also provide information about alternative enrollment options by doing... contact to learn about their enrollment options. (3) CMS may accept a nonrenewal notice submitted after... with paragraph (a)(2)(ii) of this section; and (ii) Acceptance is not inconsistent with the effective...
42 CFR 422.506 - Nonrenewal of contract.
Code of Federal Regulations, 2014 CFR
2014-10-01
... effective. The MA organization must also provide information about alternative enrollment options by doing... contact to learn about their enrollment options. (3) CMS may accept a nonrenewal notice submitted after... with paragraph (a)(2)(ii) of this section; and (ii) Acceptance is not inconsistent with the effective...
Effects of Osmolality on Paracellular Transport in MDCK II Cells
Hirai, Toyohiro; Furuse, Mikio
2016-01-01
Epithelia separate apical and basal compartments, and movement of substances via the paracellular pathway is regulated by tight junctions. Claudins are major constituents of tight junctions and involved in the regulation of tight junction permeability. On the other hand, the osmolality in the extracellular environment fluctuates in association with life activity. However, effects of osmotic changes on the permeaibility of claudins are poorly understood. Therefore, we investigated the effects of osmotic changes on the paracellular transport in MDCK II cells. Interestingly, apical hyposmolality decreased cation selectivity in the paracellular pathway gradually with time, and the elimination of the osmotic gradient promptly restored the cation selectivity. Apical hyposmolality also induced bleb formation at cell-cell contacts and changed the shape of cell-cell contacts from a jagged pattern to a slightly linear pattern. In claudin-2 knockout MDCK II cells, the decrease of cation selectivity, the bleb formation, nor the changes in the shape of cell-cell contacts was observed under the apical hyposmolality. Our findings in this study indicate that osmotic gradient between apical and basal sides is involved in the acute regulation of the cation selective property of claudin-2 channels. PMID:27855213
The Design and Implementation of Adsorptive Removal of Cu(II) from Leachate Using ANFIS
Turan, Nurdan Gamze; Ozgonenel, Okan
2013-01-01
Clinoptilolite was investigated for the removal of Cu(II) ions from industrial leachate. Adaptive neural fuzzy interface system (ANFIS) was used for modeling the batch experimental system and predicting the optimal input values, that is, initial pH, adsorbent dosage, and contact time. Experiments were studied under laboratory batch and fixed bed conditions. The outcomes of suggested ANFIS modeling were then compared to a full factorial experimental design (23), which was utilized to assess the effect of three factors on the adsorption of Cu(II) ions in aqueous leachate of industrial waste. It was observed that the optimized parameters are almost close to each other. The highest removal efficiency was found as about 93.65% at pH 6, adsorbent dosage 11.4 g/L, and contact time 33 min for batch conditions of 23 experimental design and about 90.43% at pH 5, adsorbent dosage 15 g/L and contact time 35 min for batch conditions of ANFIS. The results show that clinoptilolite is an efficient sorbent and ANFIS, which is easy to implement and is able to model the batch experimental system. PMID:23844405
Cellulose-lanthanum hydroxide nanocomposite as a selective marker for detection of toxic copper
2014-01-01
In this current report, a simple, reliable, and rapid method based on modifying the cellulose surface by doping it with different percentages of lanthanum hydroxide (i.e., 1% La(OH)3-cellulose (LC), 5% La(OH)3-cellulose (LC2), and 10% La(OH)3-cellulose (LC3)) was proposed as a selective marker for detection of copper (Cu(II)) in aqueous medium. Surface properties of the newly modified cellulose phases were confirmed by Fourier transform infrared spectroscopy, field emission scanning electron microscope, energy dispersive X-ray spectroscopy, X-ray diffraction, and X-ray photoelectron spectroscopic analysis. The effect of pH on the adsorption of modified cellulose phases for Cu(II) was evaluated, and LC3 was found to be the most selective for Cu(II) at pH 6.0. Other parameters, influencing the maximum uptake of Cu(II) on LC3, were also investigated for a deeper mechanistic understanding of the adsorption phenomena. Results showed that the adsorption capacity for Cu(II) was improved by 211% on the LC3 phase as compared to diethylaminoethyl cellulose phase after only 2 h contact time. Adsorption isotherm data established that the adsorption process nature was monolayer with a homogeneous adsorbent surface. Results displayed that the adsorption of Cu(II) onto the LC3 phase obeyed a pseudo-second-order kinetic model. Selectivity studies toward eight metal ions, i.e., Cd(II), Co(II), Cr(III), Cr(VI), Cu(II), Fe(III), Ni(II), and Zn(II), were further performed at the optimized pH value. Based on the selectivity study, it was found that Cu(II) is highly selective toward the LC3 phase. Moreover, the efficiency of the proposed method was supported by implementing it to real environmental water samples with adequate results. PMID:25258599
Gonzalez Viejo, Claudia; Fuentes, Sigfredo; Torrico, Damir D; Dunshea, Frank R
2018-06-03
Traditional methods to assess heart rate (HR) and blood pressure (BP) are intrusive and can affect results in sensory analysis of food as participants are aware of the sensors. This paper aims to validate a non-contact method to measure HR using the photoplethysmography (PPG) technique and to develop models to predict the real HR and BP based on raw video analysis (RVA) with an example application in chocolate consumption using machine learning (ML). The RVA used a computer vision algorithm based on luminosity changes on the different RGB color channels using three face-regions (forehead and both cheeks). To validate the proposed method and ML models, a home oscillometric monitor and a finger sensor were used. Results showed high correlations with the G color channel (R² = 0.83). Two ML models were developed using three face-regions: (i) Model 1 to predict HR and BP using the RVA outputs with R = 0.85 and (ii) Model 2 based on time-series prediction with HR, magnitude and luminosity from RVA inputs to HR values every second with R = 0.97. An application for the sensory analysis of chocolate showed significant correlations between changes in HR and BP with chocolate hardness and purchase intention.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Abdulla, S.; Liu, X.; Anderson, M.H.
One concept being considered for steam generation in innovative nuclear reactor applications, involves water coming into direct contact with a circulating molten metal. The vigorous agitation of the two fluids, the direct liquid-liquid contact and the consequent large interfacial area can give rise to large heat transfer coefficients and rapid steam generation. For an optimum design of such direct contact heat exchange and vaporization systems, detailed knowledge is necessary of the various flow regimes, interfacial transport phenomena, heat transfer and operational stability. In order to investigate the interfacial transport phenomena, heat transfer and operational stability of direct liquid-liquid contact, amore » series of experiments are being performed in a 1-d test facility at Argonne National Laboratory and a 2-d experimental facility at UW-Madison. Each of the experimental facilities primarily consist of a liquid-metal melt chamber, heated test section (10 cm diameter tube for 1-d facility and 10 cm 50 cm rectangle for 2-d facility), water injection system and steam suppression tank. This paper is part II which, primarily addresses results and analysis of a set of preliminary experiments and void fraction measurements conducted in the 2-d facility at UW-Madison, part I deals with the heat transfer in the 1-d test facility at Argonne National Laboratory. A real-time high energy X-ray imaging system was developed and utilized to visualize the multiphase flow and measure line-average local void fractions, time-dependent void fraction distribution as well as estimates of the vapor bubble sizes and velocities. These measurements allowed us to determine the volumetric heat transfer coefficient and gain insight into the local heat transfer mechanisms. In this study, the images were captured at frame rates of 100 fps with spatial resolution of about 7 mm with a full-field view of a 15 cm square and five different positions along the test section height. The full-field average void fraction increases rapidly to about 15% in these preliminary tests, with the apparent boiling length of less than 20 cm. The volumetric heat transfer coefficient between the liquid metal and water are compared to the CRIEPI data, the only prior data for direct contact heat exchange for these liquid metal/water systems. (authors)« less
Integrated fountain effect pump device for fluid management at low gravity
NASA Technical Reports Server (NTRS)
Yuan, S. W. K.; Frank, D. J.
1988-01-01
A new device for fluid management at low gravity is described. The system is basically the same as the enclosed capillary device using screens, in which the screens along the gallery channels are replaced by porous plugs which are responsible for both the fluid retention and pumping of He II; in this device, no downstream pump is needed. The plugs in contact with liquid He on both sides act as a fountain-effect pumps (FEPs), while plugs exposed to vapor on one side behave as vapor-liquid phase separators (VLPSs). The total net rate of He II transfer into the receiving tank equals the mass flow rate through the FEP plugs minus the liquid loss from the VLPS plugs. The results of the performance analysis of this integrated FEP device are presented together with its schematic diagram.
Hutchison, Michael G; Comper, Paul; Meeuwisse, Willem H; Echemendia, Ruben J
2015-04-01
Concussions in sports are a growing cause of concern, as these injuries can have debilitating short-term effects and little is known about the potential long-term consequences. This work aims to describe how concussions occur in the National Hockey League. Case series of medically diagnosed concussions for regular season games over a 3.5-year period during the 2006-2010 seasons. Digital video records were coded and analysed using a standardised protocol. 88% (n=174/197) of concussions involved player-to-opponent contact. 16 diagnosed concussions were a result of fighting. Of the 158 concussions that involved player-to-opponent body contact, the most common mechanisms were direct contact to the head initiated by the shoulder 42% of the time (n=66/158), by the elbow 15% (n=24/158) and by gloves in 5% of cases (n=8/158). When the results of anatomical location are combined with initial contact, almost half of these events (n=74/158) were classified as direct contact to the lateral aspect of the head. The predominant mechanism of concussion was consistently characterised by player-to-opponent contact, typically directed to the head by the shoulder, elbow or gloves. Also, several important characteristics were apparent: (1) contact was often to the lateral aspect of the head; (2) the player who suffered a concussion was often not in possession of the puck and (3) no penalty was called on the play. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.
Griffin, M; Bhandari, R; Hamilton, G; Chan, Y C; Powell, J T
1993-06-01
During alveolar development and alveolar repair close contacts are established between fibroblasts and lung epithelial cells through gaps in the basement membrane. Using co-culture systems we have investigated whether these close contacts influence synthesis and secretion of the principal surfactant apoprotein (SP-A) by cultured rat lung alveolar type II cells and the synthesis and secretion of type I collagen by fibroblasts. The alveolar type II cells remained cuboidal and grew in colonies on fibroblast feeder layers and on Matrigel-coated cell culture inserts but were progressively more flattened on fixed fibroblast monolayers and plastic. Alveolar type II cells cultured on plastic released almost all their SP-A into the medium by 4 days. Alveolar type II cells cultured on viable fibroblasts or Matrigel-coated inserts above fibroblasts accumulated SP-A in the medium at a constant rate for the first 4 days, and probably recycle SP-A by endocytosis. The amount of mRNA for SP-A was very low after 4 days of culture of alveolar type II cells on plastic, Matrigel-coated inserts or fixed fibroblast monolayers: relatively, the amount of mRNA for SP-A was increased 4-fold after culture of alveolar type II cells on viable fibroblasts. Co-culture of alveolar type II cells with confluent human dermal fibroblasts stimulated by 2- to 3-fold the secretion of collagen type I into the culture medium, even after the fibroblasts' growth had been arrested with mitomycin C. Collagen secretion, by fibroblasts, also was stimulated 2-fold by conditioned medium from alveolar type II cells cultured on Matrigel. The amount of mRNA for type I collagen increased only modestly when fibroblasts were cultured in this conditioned medium. This stimulation of type I collagen secretion diminished as the conditioned medium was diluted out, but at high dilutions further stimulation occurred, indicating that a factor that inhibited collagen secretion also was being diluted out. The conditioned medium contained low levels of IGF-1 and the stimulation of type I collagen secretion was abolished when the conditioned medium was pre-incubated with antibodies to insulin-like growth factor 1 (IGF-1). There are important reciprocal interactions between alveolar type II cells and fibroblasts in co-culture. Direct contacts between alveolar type II cells and fibroblasts appear to have a trophic effect on cultured alveolar type II cells, increasing the levels of mRNA for SP-A. Rat lung alveolar type II cells appear to release a factor (possibly IGF-1) that stimulates type I collagen secretion by fibroblasts.
Fu, Yong; Xu, Xiaoxu; Huang, Yue; Hu, Jianshe; Chen, Qifan; Wu, Yaoqing
2017-12-01
A new composite absorbent with multifunctional and environmental-friendly structures was prepared using chitosan, diatomite and polyvinyl alcohol as the raw materials, and glutaraldehyde as a cross-linking agent. The structure and morphology of the composite absorbent, and its adsorption properties of Hg(II) in water were characterized with Fourier transform infrared (FT-IR) spectra, scanning electron microscope (SEM), X-ray diffraction (XRD), Brunauer Emmett Teller (BET) measurements and ultraviolet-visible (UV-Vis) spectra. The effect of the pH value and contact time on the removal rate and absorbance of Hg(II) was discussed. The adsorption kinetic model and static adsorption isotherm and regeneration of the obtained composite absorbent were investigated. The results indicated that the removal of Hg(II) on the composite absorbent followed a rapid adsorption for 50 min, and was close to the adsorption saturation after 1 h, which is in accord with the Langmuir adsorption isotherm model and the pseudo-second-order kinetic model. When the pH value, contact time and the mass of the composite absorbent was 3, 1 h and 100 mg, respectively, the removal rate of Hg(II) on the composite absorbent reached 77%, and the maximum adsorption capacity of Hg(II) reached 195.7 mg g -1 .
Fu, Yong; Xu, Xiaoxu; Huang, Yue; Hu, Jianshe; Chen, Qifan; Wu, Yaoqing
2017-01-01
A new composite absorbent with multifunctional and environmental-friendly structures was prepared using chitosan, diatomite and polyvinyl alcohol as the raw materials, and glutaraldehyde as a cross-linking agent. The structure and morphology of the composite absorbent, and its adsorption properties of Hg(II) in water were characterized with Fourier transform infrared (FT-IR) spectra, scanning electron microscope (SEM), X-ray diffraction (XRD), Brunauer Emmett Teller (BET) measurements and ultraviolet–visible (UV–Vis) spectra. The effect of the pH value and contact time on the removal rate and absorbance of Hg(II) was discussed. The adsorption kinetic model and static adsorption isotherm and regeneration of the obtained composite absorbent were investigated. The results indicated that the removal of Hg(II) on the composite absorbent followed a rapid adsorption for 50 min, and was close to the adsorption saturation after 1 h, which is in accord with the Langmuir adsorption isotherm model and the pseudo-second-order kinetic model. When the pH value, contact time and the mass of the composite absorbent was 3, 1 h and 100 mg, respectively, the removal rate of Hg(II) on the composite absorbent reached 77%, and the maximum adsorption capacity of Hg(II) reached 195.7 mg g−1. PMID:29308226
The use of macroalgae (Gracilaria changii) as bio-adsorbent for Copper (II) removal
NASA Astrophysics Data System (ADS)
Lavania-Baloo; Idayu, Nordin; Umar Salihi, Ibrahim; Zainoddin, Jamari
2017-05-01
Biosorption of heavy metals using marine macroalgae biomass can be an effective process and alternative to conventional methods. Activated carbon was developed from macroalgae (Gracilaria changii) and used as adsorbents for the removal of copper (II) from wastewater. Gracilaria changii based activated carbon (GCBAC) was prepared using muffle furnace at a constant temperature of 300 °C for 1 hour. Batch adsorption experiments were conducted to investigate the effets of important parameters such as pH, contact time, initial metal concentration and adsorbent dosage on the removal of Cu (II) from synthetic aqueous solution. Batch adsorption study shows that removal of Cu (II) using GCBAC relied upon pH, contact time, initial metal concentration and GCBAC dosage. The optimum conditions parameters were found to be pH 6.0, time of 60 minutes and GCBAC dosage of 0.3 g, respectively. Adsorption data was described better by Freundlich isotherm model with R2 value of 0.7936. The maximum Cu (II) adsorption capacity of GCBAC was found to be 0.07 mg/g. The experimental adsorption data obtained fitted well into Pseudo-second-order kinetic model, with R2 value near unity. Thus, GCBAC can be used as an effective adsorbent for the removal of Cu (II) from aqueous solution.
Hydrodynamical models of cometary H II regions
NASA Astrophysics Data System (ADS)
Steggles, H. G.; Hoare, M. G.; Pittard, J. M.
2017-04-01
We have modelled the evolution of cometary H II regions produced by zero-age main-sequence stars of O and B spectral types, which are driving strong winds and are born off-centre from spherically symmetric cores with power-law (α = 2) density slopes. A model parameter grid was produced that spans stellar mass, age and core density. Exploring this parameter space, we investigated limb-brightening, a feature commonly seen in cometary H II regions. We found that stars with mass M⋆ ≥ 12 M⊙ produce this feature. Our models have a cavity bounded by a contact discontinuity separating hot shocked wind and ionized ambient gas that is similar in size to the surrounding H II region. Because of early pressure confinement, we did not see shocks outside of the contact discontinuity for stars with M⋆ ≤ 40 M⊙, but the cavities were found to continue to grow. The cavity size in each model plateaus as the H II region stagnates. The spectral energy distributions of our models are similar to those from identical stars evolving in uniform density fields. The turn-over frequency is slightly lower in our power-law models as a result of a higher proportion of low-density gas covered by the H II regions.
Different centre of pressure patterns within the golf stroke II: group-based analysis.
Ball, K A; Best, R J
2007-05-01
Although the golf coaching literature stresses the importance of weight transfer during the swing, research has been conflicting or lacking statistical support. A potential problem with previous studies is that no attempt was made to account for different movement strategies in the golf swing. This study evaluated the relationship between centre of pressure measures and club head velocity within two previously identified swing styles, the "Front Foot" and "Reverse" styles. Thirty-nine Front Foot golfers and 19 Reverse golfers performed swings with a driver while standing on two force plates. From the force plate data, centre of pressure displacement, velocity, range, and timing parameters were calculated. Correlation and regression analysis indicated that a larger range of centre of pressure and a more rapid centre of pressure movement in the downswing was associated with a larger club head velocity at ball contact for the Front Foot group. For the Reverse golfers, positioning the centre of pressure further from the back foot at late backswing and a more rapid centre of pressure transfer towards the back foot at ball contact was associated with a larger club head velocity at ball contact. This study has highlighted the importance of identifying different movement strategies before evaluating performance measures, as different parameters were found to be important for the Front Foot and Reverse styles.
Liu, Yan; Gao, Yanfei
2015-01-01
Biological adhesive contacts are usually of hierarchical structures, such as the clustering of hundreds of sub-micrometre spatulae on keratinous hairs of gecko feet, or the clustering of molecular bonds into focal contacts in cell adhesion. When separating these interfaces, releasable adhesion can be accomplished by asymmetric alignment of the lowest scale discrete bonds (such as the inclined spatula that leads to different peeling force when loading in different directions) or by elastic anisotropy. However, only two-dimensional contact has been analysed for the latter method (Chen & Gao 2007 J. Mech. Phys. Solids 55, 1001–1015 (doi:10.1016/j.jmps.2006.10.008)). Important questions such as the three-dimensional contact morphology, the maximum to minimum pull-off force ratio and the tunability of releasable adhesion cannot be answered. In this work, we developed a three-dimensional cohesive interface model with fictitious viscosity that is capable of simulating the de-adhesion instability and the peripheral morphology before and after the onset of instability. The two-dimensional prediction is found to significantly overestimate the maximum to minimum pull-off force ratio. Based on an interface fracture mechanics analysis, we conclude that (i) the maximum and minimum pull-off forces correspond to the largest and smallest contact stiffness, i.e. ‘stiff-adhere and compliant-release’, (ii) the fracture toughness is sensitive to the crack morphology and the initial contact shape can be designed to attain a significantly higher maximum-to-minimum pull-off force ratio than a circular contact, and (iii) since the adhesion is accomplished by clustering of discrete bonds or called bridged crack in terms of fracture mechanics terminology, the above conclusions can only be achieved when the bridging zone is significantly smaller than the contact size. This adhesion-fracture analogy study leads to mechanistic predictions that can be readily used to design biomimetics and releasable adhesives. PMID:25392403
Jafari, Maryam; Rahimi, Mahmood Reza; Ghaedi, Mehrorang; Javadian, Hamedreza; Asfaram, Arash
2017-12-01
A continuous adsorption was used for removal of azure II (AZ II) and auramine O (AO) from aqueous solutions using Pinus eldarica stalks activated carbon (PES-AC) from aqueous solutions. The effects of initial dye concentration, flow rate, bed height and contact time on removal percentage of AO and AZ II were evaluated and optimized by central composite design (CCD) at optimum pH = 7.0. ZnO nanoparticles loaded on activated carbon were also used to remove AO and AZ II at pH = 7.0 and other optimum conditions. The breakthrough curves were obtained at different flow rates, initial dye concentrations and bed heights and the experimental data were fitted by Thomas, Adams-Bohart and Yoon-Nelson models. The main parameters of fixed-bed column including its adsorption capacity at breakthrough point (q b ), adsorption capacity at saturation point (q s ), mass transfer zone (MTZ), total removal percentage (R%), and empty bed contact time (EBCT) were calculated. The removal percentages calculated for AZ II and AO II were in the range of 51.6-61.1% and 40.6-61.6%, respectively. Bed adsorption capacity (N 0 ) and critical bed depth (Z 0 ) were obtained by BDST model. Copyright © 2017 Elsevier Inc. All rights reserved.
Microbe–microbe interactions trigger Mn(II)-oxidizing gene expression
Liang, Jinsong; Bai, Yaohui; Men, Yujie; Qu, Jiuhui
2017-01-01
Manganese (Mn) is an important metal in geochemical cycles. Some microorganisms can oxidize Mn(II) to Mn oxides, which can, in turn, affect the global cycles of other elements by strong sorption and oxidation effects. Microbe–microbe interactions have important roles in a number of biological processes. However, how microbial interactions affect Mn(II) oxidation still remains unknown. Here, we investigated the interactions between two bacteria (Arthrobacter sp. and Sphingopyxis sp.) in a co-culture, which exhibited Mn(II)-oxidizing activity, although neither were able to oxidize Mn(II) in isolation. We demonstrated that the Mn(II)-oxidizing activity in co-culture was most likely induced via contact-dependent interactions. The expressed Mn(II)-oxidizing protein in the co-culture was purified and identified as a bilirubin oxidase belonging to strain Arthrobacter. Full sequencing of the bilirubin oxidase-encoding gene (boxA) was performed. The Mn(II)-oxidizing protein and the transcripts of boxA were detected in the co-culture, but not in either of the isolated cultures. This indicate that boxA was silent in Arthrobacter monoculture, and was activated in response to presence of Sphingopyxis in the co-culture. Further, transcriptomic analysis by RNA-Seq, extracellular superoxide detection and cell density quantification by flow cytometry indicate induction of boxA gene expression in Arthrobacter was co-incident with a stress response triggered by co-cultivation with Sphingopyxis. Our findings suggest the potential roles of microbial physiological responses to stress induced by other microbes in Mn(II) oxidation and extracellular superoxide production. PMID:27518809
Removal of heavy metal Cu(II) in simulated aquaculture wastewater by modified palygorskite.
Cao, Jia-Shun; Wang, Cheng; Fang, Fang; Lin, Jun-Xiong
2016-12-01
Palygorskite (PAL) is a good heavy metal adsorbent due to its high surface area, low cost, and environmentally compatibility. But the natural PAL has limited its adsorption capacity and selectivity. In this study, a cost-effective and readily-generated absorbent, l-threonine-modified palygorskite (L-PAL), was used and its performance for Cu(II) removal in simulated aquaculture wastewater was evaluated. After preparation, L-PAL was characterized by using Fourier transform infrared spectroscopy, scanning electron microscope, energy dispersive X-ray spectroscopy, X-ray diffractometer, X-ray photoelectron spectroscopy, transmission electron microscopy and thermogravimetric analysis. The impacts of pH, adsorbent dosage, contact time, and initial Cu(II) concentration on the adsorption capacity of L-PAL were examined. The Cu(II) adsorption capacity on L-PAL was enhanced almost 10 times than that of raw PAL. The adsorption isotherms of Cu(II) fit the Langmuir isotherms, and the adsorption kinetics was dominated by the pseudo-second-order model. The thermodynamic parameters at four temperatures were calculated, which indicated that the adsorption was spontaneous and endothermic. The adsorption mechanism involves complexation, chelation, electrostatic attraction, and micro-precipitation. Furthermore, L-PAL is shown to have a high regeneration capacity. These results indicate that L-PAL is a cheap and promising absorbent for Cu(II) removal and hold potential to be used for aquaculture wastewater treatment. Copyright © 2016 Elsevier Ltd. All rights reserved.
Amylopectin-g-poly(methylacrylate-co-sodium acrylate): An efficient Cd(II) binder.
Sasmal, Dinabandhu; Kolya, Haradhan; Tripathy, Tridib
2016-10-01
Synthesis, characterization and Cd(II) adsorption studies of a novel biodegradable graft copolymer based on partially hydrolysed polymethylacrylate (PMA) grafted amylopectin was reported, which was prepared by first grafting of PMA chains onto the amylopectin backbone followed by partial alkaline hydrolysis. The hydrolysed graft copolymer (PHAP) was characterized by measuring saponification equivalent (SE), FTIR, (1)H NMR and (13)C NMR spectroscopy and thermal analysis (TG/DTG). The graft copolymer was biodegradable. Various operating variables affecting the metal sorption such as, amount of adsorbent, solution pH, contact time, temperature and Cd(II) solution concentration were studied which showed that the maximum adsorption of Cd(II) was found at pH 5.5, temperature 90°C, time 120min, polymer dose, 0.02g/L and initial Cd(II) concentration, 50mg/L. The adsorption data were well described by the pseudo-second-order and Langmuir isotherm model. Metal complexation studies were carried out experimentally using UV-visible, FTIR spectroscopy and theoretically using Density Functional Theory by Gaussian 09 and Gauss view 5.0 programmes which confirms a square planer geometry involving Cd(II) and COO(-) groups. Calculation of the various thermodynamic parameters was also done. The negative value of free energy change indicates the spontaneous nature of the adsorption. Copyright © 2016 Elsevier B.V. All rights reserved.
[Land-use and urinary schistosomiasis in Daloa (Côte d'Ivoire)].
Fournet, F; N'Guessan, N A; Cadot, E
2004-02-01
The relation between agricultural land development of inland-valleys and health population has been studied in a town of the Ivorian forest area using urinary schistosomiasis as an indicator. Snails were collected during 4 months in rice fields and water holes used for market gardening of two urban inland-valleys (Batagnihi and Gakognihi). Prevalence of schistosomiasis was evaluated in two districts, Kennedy II and Fadiga, located close to the investigated inland-valleys. Schistosomiasis risk was higher in the Batagnihi where rice cultivation was more developed and prevalence of urinary schistosomiasis was higher in the Kennedy II district which is close to this inland-valley particularly among the Northern migrant people. The Kennedy II population has much more contacts with the inland-valley because of rice cultivation and social status. The higher socio-economic level of the Fadiga population limiting its contacts with the inland-valley can explain this result.
NASA Astrophysics Data System (ADS)
Rahmanian, Omid; Maleki, Mohammad Hassan; Dinari, Mohammad
2017-11-01
A novel adsorbent of nickel aluminum layered double hydroxide (Ni/Al-LDH) was prepared through the precipitation of metal nitrates by ultrasonically assisted solvothermal method. The surface morphology, chemical structure and thermal properties of this compound were examined by X-ray diffraction (XRD), Fourier Transform Infrared (FT-IR), field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), and thermogravimetric analysis (TGA) techniques. The XRD, TEM and FE-SEM results established that the synthesized LDH have a well-ordered layer structure with good crystalline nature. Then it was applied to remove excessive Cd(II) ions from water and the effects of contact time, pH and adsorbent dose were examined at initial Cd(II) concentration of 10 mg/L. Results show that the time required to reach equilibrium was fast (40 min) and working pH solution was neutral (pH 7). Langmuir and Freundlich model of adsorption isotherms were explored; the results show that the Freundlich model was better fitted than that Langmuir model. This results predicting a multilayer adsorption of Cd(II) on LDH. The equilibrium kinetic adsorption data were fixed to the pseudo-second order kinetic equation.
Kunjirama, Magendran; Saman, Norasikin; Johari, Khairiraihanna; Song, Shiow-Tien; Kong, Helen; Cheu, Siew-Chin; Lye, Jimmy Wei Ping; Mat, Hanapi
2017-06-01
This study was conducted to investigate the potential application of oil palm empty fruit branches (OPEFB) as adsorbents to remove organic methylmercurry, MeHg(II), and inorganic Hg(II) from aqueous solution. The OPEFB was functionalized with amine containing ligand namely 3-ureidopropyltriethoxysilane (UPTES) aiming for better adsorption performance towards both mercury ions. The adsorption was found to be dependent on initial pH, initial concentraton, temperatures, and contact time. The maximum adsorption capacities (Q m.exp ) of Hg(II) adsorption onto OPEFB and UPTES-OPEFB were 0.226 and 0.773 mmol/g, respectively. The Q m.exp of MeHg(II) onto OPEFB, however, was higher than UPTES-OPEFB. The adsorption kinetic data obeyed the Elovich model and the adsorption was controlled by the film-diffusion step. The calculated thermodynamic parameters indicate an endothermic adsorption process. Adsorption data analysis indicates that the adsorption mechanism may include ion-exchange, complexation, and physisorption interactions. The potential applications of adsorbents were demonstrated using oilfield produced water and natural gas condensate. The UPTES-OPEFB offered higher selectivity towards both mercury ions than OPEFB. The regenerability studies indicated that the adsorbent could be reused for multiple cycles.
21 CFR 347.52 - Labeling of astringent drug products.
Code of Federal Regulations, 2010 CFR
2010-04-01
... use only”. (ii) The labeling states “When using this product [bullet] avoid contact with eyes. If... affected area. Dry pencil after use.” (3) For products containing witch hazel identified in § 347.12(c... may be omitted. The second warning in § 347.52(c)(1) may state: “avoid contact with eyes”. The warning...
49 CFR 572.185 - Thorax (upper torso) assembly.
Code of Federal Regulations, 2010 CFR
2010-10-01
... impactor at contact with the thorax. The non-struck side arm is oriented vertically, pointing downward. The...); (iv) The impactor is guided, if needed, so that at contact with the thorax its longitudinal axis is... rib not less than 37 mm and not greater than 44 mm. (ii) The impactor force shall be computed as the...
49 CFR 572.185 - Thorax (upper torso) assembly.
Code of Federal Regulations, 2014 CFR
2014-10-01
... impactor at contact with the thorax. The non-struck side arm is oriented vertically, pointing downward. The...); (iv) The impactor is guided, if needed, so that at contact with the thorax its longitudinal axis is... rib not less than 37 mm and not greater than 44 mm. (ii) The impactor force shall be computed as the...
49 CFR 572.185 - Thorax (upper torso) assembly.
Code of Federal Regulations, 2013 CFR
2013-10-01
... impactor at contact with the thorax. The non-struck side arm is oriented vertically, pointing downward. The...); (iv) The impactor is guided, if needed, so that at contact with the thorax its longitudinal axis is... rib not less than 37 mm and not greater than 44 mm. (ii) The impactor force shall be computed as the...
49 CFR 572.185 - Thorax (upper torso) assembly.
Code of Federal Regulations, 2011 CFR
2011-10-01
... impactor at contact with the thorax. The non-struck side arm is oriented vertically, pointing downward. The...); (iv) The impactor is guided, if needed, so that at contact with the thorax its longitudinal axis is... rib not less than 37 mm and not greater than 44 mm. (ii) The impactor force shall be computed as the...
49 CFR 572.185 - Thorax (upper torso) assembly.
Code of Federal Regulations, 2012 CFR
2012-10-01
... impactor at contact with the thorax. The non-struck side arm is oriented vertically, pointing downward. The...); (iv) The impactor is guided, if needed, so that at contact with the thorax its longitudinal axis is... rib not less than 37 mm and not greater than 44 mm. (ii) The impactor force shall be computed as the...
Fragrance contact allergy in Iran.
Firooz, A; Nassiri-Kashani, M; Khatami, A; Gorouhi, F; Babakoohi, S; Montaser-Kouhsari, L; Davari, P; Dowlati, Y
2010-12-01
Fragrances are considered as one of the most common causes of allergic contact dermatitis. About 1-4% of the general population suffer from fragrance contact allergy (FCA). To determine the frequency of FCA and its clinical relevance in a sample of Iranian patients with history of contact and/or atopic dermatitis from January 2004 to December 2008. Standardized patch testing with 28-allergen screening series recommended by the German Contact Dermatitis Research Group and European Standard Series was used at six dermatological clinics in Iran. Fragrance allergens comprised of fragrance mix I (FM I), Myroxylon pereirae (MP; balsam of Peru), Lyral, turpentine and FM II. Fragrance contact allergy was detected in 7.2% of the patients. The frequency of positive reactions to FM I, MP and FM II were 3.7% (41/1105), 2.8% (32/1135) and 1.1% (3/267) respectively. 82.4% of the reactions to fragrance allergens were clinically relevant. The most common involved areas were hands (68.4%) and face (35.4%). Fragrance allergy predominantly affected women aged more than 40 years (P=0.008). Positive reaction to more than two allergens was significantly higher in FCA patients compared with other contact dermatitis patients (P<0.0001), and FM I, nickel and MP were the most frequent allergens in these patients. Despite less frequency of FCA in comparison with some European countries, its clinical relevance in Iranian patients seems to be high. It mostly affects the hands and the face predominantly in women aged more than 40 years. © 2010 The Authors. Journal compilation © 2010 European Academy of Dermatology and Venereology.
de Moraes Ferreira, Rachel; de Souza, Michael Douglas Peçanha; Takase, Iracema; de Araujo Stapelfeldt, Danielle Marques
2016-01-01
This study used two biosorbents obtained from the aquatic plants Salvinia sp. and Pistia stratiotes to establish a sustainable and alternative treatment for industrial wastewater and other water bodies that contain Pb(II). The biosorbent named Salvinia with NaOH (SOH) was obtained from Salvinia sp., and Salvinia and Pistia mixture with NaOH (SPOH) was obtained from a mixture of the two plants in a 1:1 ratio. The biosorbents were characterized by zeta potential, infrared (IR) spectroscopy, scanning electron microscopy (SEM), energy-dispersive spectroscopy and Boehm titration. The results of Boehm titration and IR analysis indicated the presence of basic functional groups, whereas those of SEM analysis indicated that the biosorbents have a structure conducive to adsorption. Batch adsorption experiments were performed to observe the effects of pH, contact time, initial lead concentration and temperature on the metal removal process. The results revealed that the biosorbents efficiently removed Pb(II) from aqueous solutions, with a maximum observed adsorption capacity (saturation limits, qmax) of 202 mg g(-1) and 210.1 mg g(-1) for SPOH and SOH, respectively. The Freundlich, Langmuir and Dubinin-Radushkevich models were applied to the data; these biosorbent studies did not satisfactorily adjust to either of the models, but the information obtained helped us understand the adsorption mechanism.
Dynamics of myosin II organization into contractile networks and fibers at the medial cell cortex
NASA Astrophysics Data System (ADS)
Nie, Wei
The cellular morphology of adhered cells depends crucially on the formation of a contractile meshwork of parallel and cross-linked stress fibers along the contacting surface. The motor activity and mini-filament assembly of non-muscle myosin II is an important component of cell-level cytoskeletal remodeling during mechanosensing. To monitor the dynamics of non-muscle myosin II, we used confocal microscopy to image cultured HeLa cells that stably express myosin regulatory light chain tagged with GFP (MRLC-GFP). MRLC-GFP was monitored in time-lapse movies at steady state and during the response of cells to varying concentrations of blebbistatin (which disrupts actomyosin stress fibers). Using image correlation spectroscopy analysis, we quantified the kinetics of disassembly and reassembly of actomyosin networks and compared to studies by other groups. This analysis suggested the following processes: myosin minifilament assembly and disassembly; aligning and contraction; myosin filament stabilization upon increasing contractile tension. Numerical simulations that include those processes capture some of the main features observed in the experiments. This study provides a framework to help interpret how different cortical myosin remodeling kinetics may contribute to different cell shape and rigidity depending on substrate stiffness. We discuss methods to monitor myosin reorganization using non-linear imaging methods.
NASA Astrophysics Data System (ADS)
Awalina; Harimawan, A.; Haryani, G. S.; Setiadi, T.
2017-05-01
The Biosorption of cadmium (II) ions on dried biomass of Aphanothece sp.which previously grown in a photobioreactor system with atmospheric carbon dioxide fed input, was studied in a batch system with respect to initial pH, biomass concentration, contact time, and temperature. The biomass exhibited the highest cadmium (II) uptake capacity at 30ºC, initial pH of 8.0±0.2 in 60 minute and initial cadmium (II) ion concentration of 7.76 mg/L. Maximum biosorption capacities were 16.47 mg/g, 54.95 mg/g and 119.05 mg/g at range of initial cadmium (II) 0.96-3.63 mg/L, 1.99-8.10 mg/L and 6.48-54.38 mg/L, respectively. Uptake kinetics follows the pseudo-second order model while equilibrium is best described by Langmuir isotherm model. Isotherms have been used to determine thermodynamic parameter process (free energy change, enthalpy change and entropy change). FTIR analysis of microalgae biomass revealed the presence of amino acids, carboxyl, hydroxyl, sulfhydryl and carbonyl groups, which are responsible for biosorption of metal ions. During repeated sorption/desorption cycles, the ratio of Cd (II) desorption to biosorption decreased from 81% (at first cycle) to only 27% (at the third cycle). Nevertheless, due to its higher biosorption capability than other adsorbent, Aphanothece sp appears to be a good biosorbent for removing metal Cd (II) ions from aqueous phase.
Contact lens wear by Royal Air Force aircrew in World War II.
Pearson, Richard M
2014-04-01
To provide an overview of the use of contact lenses by RAF aircrew in World War II by identifying some of the fitters and wearers and appraising the clinical results that they achieved. A wide-ranging literature search was undertaken that encompassed peer-reviewed journals, non-refereed publications, books, official publications, newspapers and archived documents. Thirty-one aircrew are known to have worn sealed scleral lenses in order to meet the required visual standards. Of these, only two were considered to be completely unsuccessful, one of whom was unilaterally aphakic. One additional case of undisclosed contact lens wear was found and the identity of this officer was established. Brief biographies of a few pilots establish the context of their contact lens wear. Overall, the results of scleral lens wear were variable reflecting those achieved by civilian patients of the period. While three men complained of discomfort due to heat and glare, one pilot experienced no photophobia when flying above white clouds in brilliant sunshine and another found no difficulty caused by altitude or tropical climate. Wearing time ranged from about 2h to 16, or more, hours. In about a third of the cases, wearing time was limited due to the onset of a form of contact lens induced-epithelial oedema known as Sattler's veil and effective solutions to this problem were not implemented until after the war. Copyright © 2013 British Contact Lens Association. Published by Elsevier Ltd. All rights reserved.
48 CFR 3.1004 - Contract clauses.
Code of Federal Regulations, 2011 CFR
2011-10-01
... of Hotline Poster(s), if— (i) The contract exceeds $5,000,000 or a lesser amount established by the agency; and (ii)(A) The agency has a fraud hotline poster; or (B) The contract is funded with disaster... applicable posters; and (ii) Insert the website link(s) or other contact information for obtaining the agency...
48 CFR 3.1004 - Contract clauses.
Code of Federal Regulations, 2012 CFR
2012-10-01
... of Hotline Poster(s), if— (i) The contract exceeds $5,000,000 or a lesser amount established by the agency; and (ii)(A) The agency has a fraud hotline poster; or (B) The contract is funded with disaster... applicable posters; and (ii) Insert the website link(s) or other contact information for obtaining the agency...
48 CFR 3.1004 - Contract clauses.
Code of Federal Regulations, 2014 CFR
2014-10-01
... of Hotline Poster(s), if— (i) The contract exceeds $5,000,000 or a lesser amount established by the agency; and (ii)(A) The agency has a fraud hotline poster; or (B) The contract is funded with disaster... applicable posters; and (ii) Insert the website link(s) or other contact information for obtaining the agency...
48 CFR 3.1004 - Contract clauses.
Code of Federal Regulations, 2010 CFR
2010-10-01
... of Hotline Poster(s), if— (i) The contract exceeds $5,000,000 or a lesser amount established by the agency; and (ii)(A) The agency has a fraud hotline poster; or (B) The contract is funded with disaster... applicable posters; and (ii) Insert the website link(s) or other contact information for obtaining the agency...
48 CFR 3.1004 - Contract clauses.
Code of Federal Regulations, 2013 CFR
2013-10-01
... of Hotline Poster(s), if— (i) The contract exceeds $5,000,000 or a lesser amount established by the agency; and (ii)(A) The agency has a fraud hotline poster; or (B) The contract is funded with disaster... applicable posters; and (ii) Insert the website link(s) or other contact information for obtaining the agency...
Code of Federal Regulations, 2014 CFR
2014-01-01
... CAMEL composite rating by NCUA; or (ii) A federally insured, state-chartered credit union that has been assigned a 4 or 5 CAMEL composite rating by either NCUA, after an on-site contact, or its state supervisor... union that has been assigned a 4 or 5 CAMEL rating by NCUA; or (ii) A federally insured, state-chartered...
[Work and health status of workers of shoe manufacturing industries].
Mironov, A I; Kirillov, V F; Bul'bulian, M A; Golubeva, A P; Kraeva, G K; Kuznetsova, A I; Nikolaeva, G M
2001-01-01
According to work conditions, severity and intensity, the main shoe-making occupations are assigned to III class of I-II jeopardy grade. If new technology applied, the work is assigned to I-II jeopardy class, being optimal--allowable. Increased mortality with liver cancer and lympholeucosis was revealed among workers contacting chloroprene.
Federal Register 2010, 2011, 2012, 2013, 2014
2011-02-07
... intended for non-invasive aesthetic use will need to address the issues covered in the special controls... intended for non-invasive aesthetic use. (b) Classification. Class II (special controls). The special... into class II (special controls). The special control that will apply to the device is the guidance...
Molecular self-recognition: a chiral [Mn(II)6] wheel via donor-acceptor π···π contacts and H-bonds.
Barrios, L A; Salinas-Uber, J; Roubeau, O; Teat, S J; Aromí, G
2015-03-18
A multinucleating ligand capable of establishing different types of intermolecular interactions, when combined with acetate groups leads to the assembly of a chiral [Mn(II)3] cluster poised for a process of self-recognition through a combination of perfectly complementary weak forces.
Structural Basis of Cyclic Nucleotide Selectivity in cGMP-dependent Protein Kinase II
Campbell, James C.; Kim, Jeong Joo; Li, Kevin Y.; ...
2016-01-14
Membrane-bound cGMP-dependent protein kinase (PKG) II is an important regulator of bone growth, renin secretion, and memory formation. Despite its crucial physiological roles, little is known about its cyclic nucleotide selectivity mechanism due to a lack of structural information. Here, we find that the C-terminal cyclic nucleotide binding (CNB-B) domain of PKGII binds cGMP with higher affinity and selectivity when compared with its N-terminal CNB (CNB-A) domain. To understand the structural basis of cGMP selectivity, we solved co-crystal structures of the CNB domains with cyclic nucleotides. Our structures combined with mutagenesis demonstrate that the guanine-specific contacts at Asp-412 and Arg-415more » of the αC-helix of CNB-B are crucial for cGMP selectivity and activation of PKG II. Structural comparison with the cGMP selective CNB domains of human PKG I and Plasmodium falciparum PKG (PfPKG) shows different contacts with the guanine moiety, revealing a unique cGMP selectivity mechanism for PKG II.« less
Biosorption of toxic lead (II) ions using tomato waste (Solanum lycopersicum) activated by NaOH
NASA Astrophysics Data System (ADS)
Permatasari, Diah; Heraldy, Eddy; Lestari, Witri Wahyu
2016-02-01
This research present to uptake lead (II) ion from aqueous solutions by activated tomato waste. Biosorbent were characterized by applying Fourier Transform Infrared Spectroscopy (FTIR) and Surface Area Analyzer (SAA). The biosorption investigated with parameters including the concentration of NaOH, effects of solution pH, biosorbent dosage, contact time,and initial metal concentration. Experimental data were analyzed in terms of two kinetic model such us the pseudo-first order and pseudo-second order. Langmuir and Freundlich isotherm models were applied todescribe the biosorption process. According to the experiment, the optimum concentration of NaOH was achieved at 0.1 M. The maximum % lead (II) removal was achieved at pH 4 with 94.5%. Optimum biosorbentdosage were found as 0.1 g/25 mL solution while optimum contact time were found at 75 minutes. The results showed that the biosorption processes of Lead (II) followed pseudo-second order kinetics. Langmuir adsorption isotherm was found fit the adsorption data with amaximum capacity of 24.079 mg/g with anadsorption energy of 28.046 kJ/mol.
Biosorption of lead (II) ions by NaOH-activated apple (Malus domestica) juice residue
NASA Astrophysics Data System (ADS)
Arimurti, Devita Dwi; Heraldy, Eddy; Lestari, Witri Wahyu
2016-02-01
This research studied the removal of Pb(II) ions from aqueous solutions using NaOH-activated apple (Malus domestica) juice residue. Biosorbent was characterized with Fourier Transform Infrared Spectrophotometer (FTIR), and Surface Area Analyzer (SAA). The effects of biosorbent dosage, pH, contact time and initial metal ion concentration had been investigated in batch-adsorption method. The biosorption kinetic data were analyzed by pseudo-first-order and pseudo-second-order kinetics model. Freundlich and Langmuir's isotherm were used to describe the biosorption process. The optimum conditions of Pb(II) adsorption was observed at 60 min of contact time, pH 4, and 0.1 g biosorbent dosage in 25 ml solution. The biosorption kinetics followed the pseudo-second-order kinetic model, resulted biosorption constant rate of 0.184 g.mg-1.min-1. The Langmuir isotherm model exhibited the best fit to experimental data. The maximum biosorption capacity of Pb(II) determined according to the Langmuir model was 90.90 mg.g-1 at 302 K, with the adsorption energy of 26.429 kJ.mol-1.
NASA Astrophysics Data System (ADS)
Nbili, W.; Kaabi, K.; Ferenc, W.; Cristovão, B.; Lefebvre, F.; Jelsch, Christian; Ben Nasr, Cherif
2017-02-01
A new Cu(II) complex with the bridge bidentate ligand 4-amino-6-methoxypyrimidine, [Cu(C5H7N3O)(H2O)(NO3)2], has been prepared at room temperature and characterized by single crystal X-ray diffraction and IR spectroscopy. The compound crystallizes in the monoclinic space group C2/c with lattice parameters a = 17.783 (4), b = 11.131 (3), c = 12.594 (3) Å, β = 117.616 (3)°, V = 2209.0 (9) Å3 and Z = 8. The Cu(II) cation is hexa-coordinated, in distorted octahedral fashion, by two nitrogen atoms of two 4-amino-6-methoxypyrimidine ligands, one water oxygen atom and three oxygen atoms of two nitrate anions. In the atomic arrangement, the organic ligands and the 6-connected Cu centers are linked with each other to give a 1-D corrugated chain running along the b-axis direction. The chains are interconnected via Osbnd H⋯O, Csbnd H⋯O, Nsbnd H⋯O hydrogen bonds to form a three dimensional network. The analysis of contacts on the Hirshfeld surface shows that the crystal packing is driven mainly by the electrostatic interactions: the coordination of Cu(II) by O and N as well as strong hydrogen bonds. The vibrational absorption bands were identified by infrared spectroscopy. Magnetic properties were also studied to characterize the complex.
Kwon, Oh-Hun; Kim, Jong-Oh; Cho, Dong-Wan; Kumar, Rahul; Baek, Seung Han; Kurade, Mayur B; Jeon, Byong-Hun
2016-10-01
A composite adsorbent to remove arsenite [As(III)], arsenate [As(V)], and copper [Cu(II)] from aqueous phase was synthesized by immobilizing zirconium oxide on alginate beads (ZOAB). The composition (wt%) of ZOAB (Zr-34.0; O-32.7; C-21.3; Ca-1.0) was confirmed by energy dispersive X-ray (EDX) analysis. Sorption studies were conducted on single and binary sorbate systems, and the effects of contact time, initial adsorbate concentration, and pH on the adsorption performance of ZOAB (pHPZC = 4.3) were monitored. The sorption process for As(III)/As(V) and Cu(II) reached an equilibrium state within 240 h and 24 h, respectively, with maximum sorption capacities of 32.3, 28.5, and 69.9 mg g(-1), respectively. The addition of Cu(II) was favorable for As(V) sorption in contrast to As(III). In the presence of 48.6 mg L(-1) Cu(II), the sorption capacity of As(V) increased from 1.5 to 3.8 mg g(-1) after 240 h. The sorption data for As(III)/As(V) and Cu(II) conformed the Freundlich and Langmuir isotherm models, respectively. The adsorption of As(III), As(V), and Cu(II) followed pseudo second order kinetics. The effect of arsenic species on Cu(II) sorption was insignificant. The results of present study demonstrated that the synthesized sorbent could be useful for the simultaneous removal of both anionic and cationic contaminants from wastewaters. Copyright © 2016 Elsevier Ltd. All rights reserved.
Stratigraphy in Apollo 16 drill section 60002
NASA Technical Reports Server (NTRS)
Blanford, G. E.; Morrison, D. A.
1976-01-01
Contacts in drill stem 60002 which indicate layers at least several centimeters thick and with one firm age of about 2.5 x 10 to the 7th yr are observed on the basis of characteristic patterns of track density variation with depth from the contact. The patterns can be observed primarily because the drill stem has a large immature component (path II soils).
Unraveling orbital hybridization of triplet emitters at the metal-organic interface.
Ewen, Pascal R; Sanning, Jan; Doltsinis, Nikos L; Mauro, Matteo; Strassert, Cristian A; Wegner, Daniel
2013-12-27
We have investigated the structural and electronic properties of phosphorescent planar platinum(II) complexes at the interface of Au(111) with submolecular resolution using combined scanning tunneling microscopy and spectroscopy as well as density functional theory. Our analysis shows that molecule-substrate coupling and lateral intermolecular interactions are weak. While the ligand orbitals remain essentially unchanged upon contact with the substrate, we found modified electronic behavior at the Pt atom due to local hybridization and charge transfer to the substrate. Thus, this novel class of phosphorescent molecules exhibits well-defined and tunable interaction with its local environment.
2012-10-15
0.45 .015 .0005 Si = 0.08, Cr = 0.04, Zr = 0.03, Nb , Ta, W, V < 0.01, Bi, Pb, Ag, Sn< 0.0005 wt pet Page | 7 Table 2. Mechanical Properties...analysis and contribute to dcPD increase due to plasticity-based resistivity increase. Additionally, crack surface electrical contact which changes during...STTR-II sponsored). Task 2-3 Produce laboratory measurements of HEAC resistance (KIH, da/dtn, and da/dt vs. stress intensity factor) for a single
On SYM theory and all order bulk singularity structures of BPS strings in type II theory
NASA Astrophysics Data System (ADS)
Hatefi, Ehsan
2018-06-01
The complete forms of the S-matrix elements of a transverse scalar field, two world volume gauge fields, and a Potential Cn-1 Ramond-Ramond (RR) form field are investigated. In order to find an infinite number of t , s , (t + s + u)-channel bulk singularity structures of this particular mixed open-closed amplitude, we employ all the conformal field theory techniques to
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jin, Xin; Zhou, Pei; Zheng, Chunying
A copper complex ([Cu(py){sub 2}(L){sub 2}]·2CH{sub 3}OH){sub n} (HL=(E)-3-(3-hydroxyl-phenyl)-acrylic acid) (1) with acrylic acid ligand was synthesized and structurally analyzed by IR, elemental analysis, TGA and the single-crystal X-ray diffraction methods. It is the first time to find that phenolic hydroxyl of L coordinates to Cu(II). Complex 1 exhibits 1D chain by a double-bridge of ligands, and the 3D supramolecular framework in complex 1 is constructed by π–π stacking interactions and van der Waals Contacts among the 1D chains. The magnetic properties of complex 1 have been studied. - Graphical abstract: A copper complex based on (E)-3-(3-hydroxyl-phenyl)-acrylic acid in amore » novel coordinated way was synthesized and a ferromagnetic exchange interactions between neighboring Cu(II) ions has be achieved. - Highlights: • A new copper complex with acrylic acid ligand was synthesized and analyzed. • We find the phenolic hydroxyl of MCA ligand coordinates to metal ion firstly. • A ferromagnetic exchange interactions between Cu(II) ions has been achieved.« less
Polymeric hydrogels for novel contact lens-based ophthalmic drug delivery systems: a review.
Xinming, Li; Yingde, Cui; Lloyd, Andrew W; Mikhalovsky, Sergey V; Sandeman, Susan R; Howel, Carol A; Liewen, Liao
2008-04-01
Only about 5% of drugs administrated by eye drops are bioavailable, and currently eye drops account for more than 90% of all ophthalmic formulations. The bioavailability of ophthalmic drugs can be improved by a soft contact lens-based ophthalmic drug delivery system. Several polymeric hydrogels have been investigated for soft contact lens-based ophthalmic drug delivery systems: (i) polymeric hydrogels for conventional contact lens to absorb and release ophthalmic drugs; (ii) polymeric hydrogels for piggyback contact lens combining with a drug plate or drug solution; (iii) surface-modified polymeric hydrogels to immobilize drugs on the surface of contact lenses; (iv) polymeric hydrogels for inclusion of drugs in a colloidal structure dispersed in the lens; (v) ion ligand-containing polymeric hydrogels; (vi) molecularly imprinted polymeric hydrogels which provide the contact lens with a high affinity and selectivity for a given drug. Polymeric hydrogels for these contact lens-based ophthalmic drug delivery systems, their advantages and drawbacks are critically analyzed in this review.
Effect of Hydrofluoric Acid Concentration on Resin Adhesion to a Feldspathic Ceramic.
Venturini, Andressa Borin; Prochnow, Catina; Rambo, Dagma; Gundel, Andre; Valandro, Luiz Felipe
2015-08-01
To evaluate the effect of different concentrations of hydrofluoric acid (HF) on the contact angle and the resin bond strength durability to feldspathic ceramic. To evaluate the contact angles of distilled water on etched feldspathic ceramic, 25 specimens (12×10×2.4 mm) of VitaBlocks Mark II were used, divided into 5 groups (n=5): one unconditioned control (UC) group with no ceramic surface treatment, and 4 other groups that were etched for 60 s with different concentrations of HF: 1% (HF1), 3% (HF3), 5% (HF5) and 10% (HF10). The bond testing utilized 40 ceramic blocks (12×10×4 mm) that were fabricated and subjected to the same surface treatments as previously mentioned (excluding the control). The etched surfaces were silanized and resin cement was applied. After 24 h, the blocks were sectioned to produce bar specimens that were divided into two groups, non-aged (immediate testing) and aged (storage for 230 days+12,000 thermocycles at 5°C and 55°C), and subjected to microtensile testing (μTBS). Micromorphogical analysis of the treated surfaces was also performed (atomic force and scanning electron microscopy). One-way ANOVA and Tukey's tests were applied for data analysis. UC had the highest contact angle (61.4°), whereas HF10 showed the lowest contact angle (17.5°). In non-aged conditions, different acids promoted statistically similar bond strengths (14.2 to 15.7 MPa) (p>0.05); in terms of bond durability, only the bond strength of the HF1 group presented a statistically significant decrease comparing before and after aging (14.5 to 10.2 MPa). When etched with 3%, 5%, or 10% hydrofluoric acid, the ceramic tested showed stable resin adhesion after long-term aging.
Semilocal momentum-space regularized chiral two-nucleon potentials up to fifth order
NASA Astrophysics Data System (ADS)
Reinert, P.; Krebs, H.; Epelbaum, E.
2018-05-01
We introduce new semilocal two-nucleon potentials up to fifth order in the chiral expansion. We employ a simple regularization approach for the pion exchange contributions which i) maintains the long-range part of the interaction, ii) is implemented in momentum space and iii) can be straightforwardly applied to regularize many-body forces and current operators. We discuss in detail the two-nucleon contact interactions at fourth order and demonstrate that three terms out of fifteen used in previous calculations can be eliminated via suitably chosen unitary transformations. The removal of the redundant contact terms results in a drastic simplification of the fits to scattering data and leads to interactions which are much softer ( i.e., more perturbative) than our recent semilocal coordinate-space regularized potentials. Using the pion-nucleon low-energy constants from matching pion-nucleon Roy-Steiner equations to chiral perturbation theory, we perform a comprehensive analysis of nucleon-nucleon scattering and the deuteron properties up to fifth chiral order and study the impact of the leading F-wave two-nucleon contact interactions which appear at sixth order. The resulting chiral potentials at fifth order lead to an outstanding description of the proton-proton and neutron-proton scattering data from the self-consistent Granada-2013 database below the pion production threshold, which is significantly better than for any other chiral potential. For the first time, the chiral potentials match in precision and even outperform the available high-precision phenomenological potentials, while the number of adjustable parameters is, at the same time, reduced by about ˜ 40%. Last but not least, we perform a detailed error analysis and, in particular, quantify for the first time the statistical uncertainties of the fourth- and the considered sixth-order contact interactions.
Development and preliminary testing of an instrumented object for force analysis during grasping.
Romeo, R A; Cordella, F; Zollo, L; Formica, D; Saccomandi, P; Schena, E; Carpino, G; Davalli, A; Sacchetti, R; Guglielmelli, E
2015-01-01
This paper presents the design and realization of an instrumented object for force analysis during grasping. The object, with spherical shape, has been constructed with three contact areas in order to allow performing a tripod grasp. Force Sensing Resistor (FSR) sensors have been employed for normal force measurements, while an accelerometer has been used for slip detection. An electronic board for data acquisition has been embedded into the object, so that only the cables for power supply exit from it. Validation tests have been carried out for: (i) comparing the force measurements with a ground truth; (ii) assessing the capability of the accelerometer to detect slippage for different roughness values; (iii) evaluating object performance in grasp trials performed by a human subject.
Adsorption of Cu(II) Ions in Aqueous Solutions by HCl Activated Carbon of Oil Palm
NASA Astrophysics Data System (ADS)
Muslim, A.; Syamsuddin, Y.; Salamun, A.; Abubakar; Ramadhan, D.; Peiono, D.
2017-06-01
Activated carbon was prepared from oil palm empty fruit bunch (OPEFB) by pyrolysis at 873.15 K in a furnace and chemical activation using 0.01 M HCl. Fourier Transform Infrared Spectroscopy, Scanning Electron Microscopy and BET (Brunauer, Emmett and Teller) surface area analyses were taken into account to investigate the chemical functional group, to characterise the surface morphology and to determine total surface area the OPEFB AC, respectively. Experiments in batch mode were conducted to investigate Cu(II) adsorption capacity by the OPEFB AC whereas the system consisted of 1 g the OPEFB AC in 100 mL Cu(II) aqueous solution with initial concentration in the range of 10-70 mg/L, magnetic stirring at 75 rpm, room temperature of 300.15 K (± 2 K), at 1 atm and neutral pH over contact time in the range of 0-150 min. As the result, Cu(II) adsorption capacity increased exponentially over contact time and initial concentration. The Cu(II) adsorption kinetics followed the pseudo second order kinetics with the correlation coefficients (R 2), kinetics rate constant and equilibrium adsorption capacity being 0.98, 4.81 mg/g and 0.15/min, respectively for initial Cu(II) concentration being 58.71 mg/L. In addition, Cu(II) adsorption isotherm followed the Langmuir equation with the R2 value, the mono-layer and over-all adsorption capacity being 0.99, 5.92 mg/g and 0.17 L/mg, respectively.
NASA Astrophysics Data System (ADS)
Cairo, Raúl Ramos; Stevens, Ana María Plutín; de Oliveira, Tamires Donizeth; Batista, Alzir A.; Castellano, Eduardo E.; Duque, Julio; Soria, Delia B.; Fantoni, Adolfo C.; Corrêa, Rodrigo S.; Erben, Mauricio F.
2017-04-01
1-Acyl thioureas [R1C(O)NHC(S)NR2R3] are shown to display conformational flexibility depending on the degree of substitution at the nitrogen atom. The conformational landscape and structural features for two closely related thioureas having R1 = 2-furoyl have been studied. The un-substituted 2-furoyl thiourea (I) and its dimethyl analogue, i.e. 1-(2-furoyl)-3,3-dimethyl thiourea (II), have been synthesized and fully characterized by spectroscopic (FT-IR, 1H and 13C NMR) and elemental analysis. According to single crystal X-ray diffraction analysis, compounds I and II crystallize in the monoclinic space group P21/c. In the compound I, the trans-cis geometry of the almost planar thiourea unit is stabilized by intramolecular Nsbnd H ⋯ Odbnd C hydrogen bond between the H atom of the cis thioamide and the carbonyl O atom. In compound II, however, the acyl thiourea group is non-planar, in good agreement with the potential energy curve computed at the B3LYP/6-31 + G(d,p) level of approximation. Centrosymmetric dimers generated by intermolecular Nsbnd H ⋯ Sdbnd C hydrogen bond forming R22(8) motif are present in the crystals. Intermolecular interactions have been rationalized in terms of topological partitions of the electron distributions and Hirshfeld surface analysis, which showed the occurrence of S ⋯ H, O ⋯ H and H ⋯ H contacts that display an important role to crystal packing stabilization of both thiourea derivatives.
Azzam, Eid M S; Eshaq, Gh; Rabie, A M; Bakr, A A; Abd-Elaal, Ali A; El Metwally, A E; Tawfik, Salah M
2016-08-01
In the present study, chitosan assembled on gold and silver nanoparticles were prepared and characterized by UV-vis, TEM, EDX and DLS techniques. The nanocomposites chitosan (Ch)/clay, chitosan (Ch)/AgNPs/clay and chitosan (Ch)/AuNPs/clay were prepared by solution mixing method and characterized by FTIR, XRD, and SEM techniques. The adsorption of copper(II) ions onto the prepared hybrid composites from an aqueous solution using batch adsorption was examined. The results showed that benefiting from the surface property of clay, the abundant amino and hydroxyl functional groups of chitosan, the adsorbent provides adequate and versatile adsorption for the Cu(II) ions under investigation. The batch adsorption experiments showed that the adsorption of the Cu(II) is considerably dependent on pH of milieu, the amount of adsorbent, and contact time. Batch adsorption studies revealed that the adsorption capacity of Cu(II) increased with increase in initial concentration and contact time with optimum pH in the range around neutral. The maximum uptake of Cu(II) ions by (Ch)/AgNPs/clay composite was found to be 181.5mg/g. The adsorption efficiency of Cu(II) ions by prepared (Ch)/AgNPs/clay and (Ch)/AuNPs/clay is bigger than that the individual chitosan (Ch)/clay composite which clarifies the role of metal nanoparticles in enhancement the adsorption characters. The study suggests that the (Ch)/AgNPs/clay hybrid composite is a promising nano-adsorbent for the removal of Cu(II) ions from aqueous solution. Copyright © 2016 Elsevier B.V. All rights reserved.
16 CFR 1215.2 - Requirements for infant bath seats.
Code of Federal Regulations, 2012 CFR
2012-01-01
... degrees. Measure and record the pre-test angle of the test bar. (ii) [Reserved] (5) Between section 7.4.2...)—(Angle measured pre-test). (ii) [Reserved] (6) Instead of complying with the first sentence in section 7... with 7.4. In addition, if any attachment point disengages from (is no longer in contact with) the test...
16 CFR 1215.2 - Requirements for infant bath seats.
Code of Federal Regulations, 2011 CFR
2011-01-01
... degrees. Measure and record the pre-test angle of the test bar. (ii) [Reserved] (5) Between section 7.4.2...)—(Angle measured pre-test). (ii) [Reserved] (6) Instead of complying with the first sentence in section 7... with 7.4. In addition, if any attachment point disengages from (is no longer in contact with) the test...
A study of cross-reactions between mango contact allergens and urushiol.
Oka, Keiko; Saito, Fumio; Yasuhara, Tadashi; Sugimoto, Akiko
2004-01-01
The allergens causing mango dermatitis have long been suspected to be alk(en)yl catechols and/or alk(en)yl resorcinols on the basis of observed cross-sensitivity reactions to mango in patients known to be sensitive to poison ivy and oak (Toxicodendron spp.). Earlier, we reported the 3 resorcinol derivatives: heptadecadienylresorcinol (I), heptadecenylresorcinol (II) and pentadecylresorcinol (III); collectively named 'mangol', as mango allergens. In this study, we extracted the 1st 2 components (I and II) from the Philippine mango, adjusted them to 0.05% concentration in petrolatum and patch tested the components on 2 subjects with mango dermatitis. Both subjects reacted to I. 1 subject also elicited a weaker positive reaction to II. To investigate the cross-reaction between mangol and urushiol, we also patch tested the same subjects with urushiol. The subject sensitive to II reacted to urushiol. 6 subjects with a history of lacquer contact dermatitis and positive reactions to urushiol were similarly patch tested. 5 persons reacted to I. 2 subjects also exhibited a slower but positive reaction to II. This is the 1st report in which heptadec(adi)enyl resorcinols known to be present in mango have been shown to elicit positive patch test reactions in mango-sensitive patients.
Bikbaeva, Zarina M; Ivanov, Daniil M; Novikov, Alexander S; Ananyev, Ivan V; Bokach, Nadezhda A; Kukushkin, Vadim Yu
2017-11-06
The nitrosoguanidinate complex [Ni{NH═C(NMe 2 )NN(O)} 2 ] (1) was cocrystallized with I 2 and sym-trifluorotriiodobenzene (FIB) to give associates 1·2I 2 and 1·2FIB. Structures of these solid species were studied by XRD followed by topological analysis of the electron density distribution within the framework of Bader's approach (QTAIM) at the M06/DZP-DKH level of theory and Hirshfeld surface analysis. Our results along with inspection of XRD (CCDC) data, accompanied by the theoretical calculations, allowed the identification of three types of Ni···I contacts. The Ni···I semicoordination of the electrophilic nickel(II) center with electron belt of I 2 was observed in 1·2I 2 , the metal-involving halogen bonding between the nucleophilic nickel(II)-d z 2 center and σ-hole of iodine center was recognized and confirmed theoretically in the structure of [FeNi(CN) 4 (IPz)(H 2 O)] n (IPz = 4-N-coordinated 2-I-pyrazine), whereas the arrangement of FIB in 1·2FIB provides a boundary case between the semicoordination and the halogen Ni···I bondings. In 1·2I 2 and 1·2FIB, noncovalent interactions were studied by variable temperature XRD detecting the expansion of noncovalent contacts with preservation of covalent bond lengths upon the temperature increase from 100 to 300 K. The nature and energies of all identified types of the Ni···I noncovalent interactions in the obtained (1·2I 2 and 1·2FIB) and in the previously reported ([FeNi(CN) 4 (IPz)(H 2 O)] n , [NiL 2 ](I 3 ) 2 ·2I 2 (L = o-phenylene-bis(dimethylphosphine), [NiL]I 2 (L = 1,4,8,11-tetra-azacyclotetradecane), Ni(en) 2 ] n [AgI 2 ] 2n (en = ethylenediamine), and [NiL](ClO 4 ) (L = 4-iodo-2-((2-(2-(2-pyridyl)ethylsulfanyl)ethylimino)methyl)-phenolate)) structures were studied theoretically. The estimated strengths of these Ni···I noncovalent contacts vary from 1.6 to 4.1 kcal/mol and, as expected, become weaker on heating. This work is the first emphasizing electrophilic-nucleophilic dualism of any metal center toward noncovalent interactions.
Reductive Dechlorination of Carbon Tetrachloride by Soil With Ferrous and Bisulfide
NASA Astrophysics Data System (ADS)
Choi, K.; Lee, W.
2008-12-01
Batch and column experiments were conducted to investigate the effect of concentration of reductants, contact time to activate reductive capacity, and pH on reductive dechlorination by soil with Fe(II) and HS- in this study. Carbon tetrachloride (CT) was used as a representative target organic compound. Sorption kinetic and isotherm tests were performed to investigate the influence of adsorption on the soil surface. Target compound in the soil suspension reached sorption equilibrium in 4 hours and the type of isotherm was well fitted by a linear type isotherm. In batch experiment, kinetic rate constants for the reductive dechlorination of CT increased with increasing the concentration of the reductants (Fe(II) and HS-). However, Fe(II) was a much more effective reductant, producing higher k values than those of HS-. The contact time of one day for the soil with HS- and that of four hours with Fe(II) showed the highest reaction rates. Additionally, the rate constants increased with the increase of pH in soil suspension with Fe(II) (5.2~8) and HS- (8.3~10.3), respectively. In column experiment, the soil column with Fe(II) showed larger bed volumes (13.76) to reach a column breakthrough than that with HS- indicating the treatment of Fe(II) is more effective for the reductive dechlorination of CT. To enhance reductive capacity of soil column under an acidic condition, CaO addition to the column treated with Fe(II) showed better results for the reductive dechlorination of CT than that of HS-. Fe(II) showed better CT dechlorination than HS- in batch and column reactors therefore, it can be used as an effective reducing agent for the treatment of soil contaminated with chlorinated organic compounds.
Jenkins, R A; Chinaworapong, S; Morgan, P A; Ruangyuttikarn, C; Sontirat, A; Chiu, J; Michael, R A; Nitayaphan, S; Khamboonruang, C
1998-06-01
Data from recruitment and screening for a phase I/II preventive HIV-1 vaccine trial in Thailand were evaluated with respect to correlates of participation at each phase. Correlates included demographic variables, motivation for interest in the trial, and factors related to communication and contact. Participants were recruited at two sites through varied methods. The majority of prescreenees reported altruistic motives for interest in the trial and blood donors emerged as a group that may have been particularly altruistic. Findings indicated site differences in attrition during recruitment and screening, but not in enrollment into the vaccine trial. Blood donation and willingness to be contacted by phone at home were significantly related to making and keeping screening appointments.
Graham-Phillips, Anita; Roth, David L; Huang, Jin; Dilworth-Anderson, Peggye; Gitlin, Laura N
2016-08-01
To determine whether there are racial and ethnicity group differences in Resources for Enhancing Alzheimer's Caregiver Health (REACH II) intervention delivery. Randomized controlled trial. Community-based intervention delivered at five sites across the United States. Family caregivers of persons with dementia who were randomized to the active intervention condition (N = 323). Nine in-home sessions (90 minutes each) and three telephone sessions (30 minutes each) were intended to be delivered and designed to reduce caregiver burden and depression, improve caregiver self-care and social support, and help caregivers manage behavior problems in persons with dementia. Interventionists recorded the type of intervention (home or telephone), start and stop times, and whether specific intervention content modules (e.g., stress management, social support) were administered in each session. Overall, REACH II intervention delivery was high, with more than 80% of randomized caregivers completing at least five in-home sessions and receiving eight or more hours of intervention contact, but black caregivers completed fewer in-home sessions (mean 6.98) than Hispanics (mean 7.84) or whites (mean 8.25) and received less total intervention contact time (mean 683 minutes) than Hispanics (mean 842 minutes) or whites (mean 798 minutes). No significant differences in exposure to content according to race or ethnicity were found after controlling for demographic covariates. Blacks in REACH II received significantly less intervention contact. Similar multicomponent interventions should examine whether there are systematic differences in intervention delivery across specific demographic subgroups and explore implications for treatment outcomes. © 2016, Copyright the Authors Journal compilation © 2016, The American Geriatrics Society.
Yao, Shuheng; Zhang, Jiajun; Shen, Dekui; Xiao, Rui; Gu, Sai; Zhao, Ming; Liang, Junyu
2016-02-01
The rice husk based activated carbon (RH-AC) was treated by nitric acid under microwave heating, in order to improve its capability for the removal of heavy metal ions from water. The optimal conditions for the modification of RH-AC (M-RH-AC) were determined by means of orthogonal array experimental design, giving those as the concentration of nitric acid of 8mol/L, modification time of 15min, modification temperature of 130°C and microwave power of 800W. The characteristics of the M-RH-AC and RH-AC were examined by BET, XRD, Raman spectrum, pH titration, zeta potential, Boehm titration and FTIR analysis. The M-RH-AC has lower pore surface area, smaller crystallite, lower pHIEP and more oxygen-containing functional groups than the RH-AC. Removal capacity of Pb(II) ions by the M-RH-AC and RH-AC from water solution was estimated concerning the influence of contact time, pH value, and initial concentration. The equilibrium time of Pb(II) removal was found to be around 90min after modification process. Two kinetic models are adopted to describe the possible Pb(II) adsorption mechanism, finding that the adsorption rate of Pb(II) ions by the M-RH-AC is larger than that of RH-AC. Copyright © 2015 Elsevier Inc. All rights reserved.
NASA Astrophysics Data System (ADS)
Binzet, Gun; Gumus, Ilkay; Dogen, Aylin; Flörke, Ulrich; Kulcu, Nevzat; Arslan, Hakan
2018-06-01
We synthesized four new N,N-dialkyl-N‧-3-chlorobenzoylthiourea ligands (Alkyl: Dimethyl, diethyl, di-n-propyl and di-n-butyl) and their metal complexes with copper and nickel atoms. The structure of all synthesized compounds was fully characterized by physicochemical, spectroscopic and single crystal X-ray diffraction analysis techniques. The physical, spectral and analytical data of the newly synthesized metal complexes have shown the formation of 1:2 (metal:ligand) ratio. The benzoylthiourea ligands coordinate with metal atoms through oxygen and sulphur atoms. The metal atoms are in slightly distorted square-planar coordination geometry in Ni(II) or Cu(II) complex. Two oxygen and two sulphur atoms are mutually cis to each other in Ni(II) or Cu(II) complex. The intermolecular contacts in the compounds, which are HL1 and HL3, were examined by Hirshfeld surfaces and fingerprint plots using the data obtained from X-ray single crystal diffraction measurement. Besides these, their antimicrobial activities against Gram-positive bacteria (Bacillus subtilis, Staphylococcus aureus, Streptococcus pyogenes and Enterococcus faecalis) and Gram-negative bacteria (Escherichia coli and Pseudomonas aeruginosa) and anti-yeast activity (Candida glabrata, Candida parapsilosis and Candida albicans) were investigated. This exhibited some promising results towards testing organism. Among all the compounds, Ni(L1)2 complex showed high activity against Bacillus subtilis with MIC values at 7.81 μg/mL.
Cd(II) removal on surface-modified activated carbon: equilibrium, kinetics and mechanism.
Liang, Jianjun; Liu, Meiling; Zhang, Yufei
2016-10-01
Commercial pulverous activated carbon (AC-0) was modified through two steps: oxidize AC-0 acid firstly, impregnate it with iron using ferric chloride secondly. Orthogonal experiment was conducted then to prepare modified activated carbon with high Cd(II) adsorption capacity (ACNF). Batch adsorption experiments were undertaken to determine the adsorption characteristics of Cd(II) from aqueous solution onto AC-0 and ACNF and the effect of pH, contact time and initial Cd(II) concentration. The results indicate that: the adsorption behavior of Cd(II) on ACNF can be well fitted with Langmuir model, and the maximum adsorption capacity of ACNF was 2.3 times higher than that of AC-0, supporting a monolayer coverage of Cd(II) on the surface. The kinetics of the adsorption process can be described by pseudo-second-order rate equation very well, and the adsorption capacity increased from 0.810 mg/g to 0.960 mg/g after modification. Compared with AC-0, the kinetic parameters of ACNF showed a higher adsorption rate through the aqueous solution to the solid surface and a lower intraparticle diffusion rate. Surface modification resulted in a lower Brunauer-Emmett-Teller (BET) surface area and pore size because of the collapse and blockage of pores, according to the X-ray diffraction (XRD) analysis, while the total number of surface oxygen acid groups increased, and this was supposed to contribute to the enhanced adsorption capacity of modified activated carbon.
Small nanoparticles, surface geometry and contact forces.
Takato, Yoichi; Benson, Michael E; Sen, Surajit
2018-03-01
In this molecular dynamics study, we examine the local surface geometric effects of the normal impact force between two approximately spherical nanoparticles that collide in a vacuum. Three types of surface geometries-(i) crystal facets, (ii) sharp edges, and (iii) amorphous surfaces of small nanoparticles with radii R <10 nm-are considered. The impact forces are compared with their macroscopic counterparts described by nonlinear contact forces based on Hertz contact mechanics. In our simulations, edge and amorphous surface contacts with weak surface energy reveal that the average impact forces are in excellent agreement with the Hertz contact force. On the other hand, facet collisions show a linearly increasing force with increasing compression. Our results suggest that the nearly spherical nanoparticles are likely to enable some nonlinear dynamic phenomena, such as breathers and solitary waves observed in granular materials, both originating from the nonlinear contact force.
Yamaguchi, Daichi
2018-06-05
The image quality of laser and multi-function printers that make use of electrophotography depends on the amount of surface charge generated by contact electrification on the toner particles. However, because it has been impossible to experimentally evaluate such amounts under controlled contact conditions using macroscopic measurements, theoretical elucidation of the contact electrification mechanism has not progressed sufficiently. In the present study, we have developed a system to experimentally evaluate the contact electrification of a single particle using atomic force microscopy (AFM) and nanotweezers (microelectromechanical systems (MEMS)-based actuated tweezers). This system performs, in succession, (i) a contact test that makes use of the nanotweezers and three piezoelectric stages, and (ii) an image force measurement using the AFM cantilever. Using this system, contact electrification was evaluated under controlled conditions, such as the contact number and the indentation depth. In addition, differences in contact electrification due to the amount of external surface additives were investigated. The results reveal that a coating with external additives leads to a decrease in the amount of contact electrification due to a reduction in the contact area with the substrate.
Kerstein, Robert B
2004-04-01
Current advances in computer technologies have afforded dentists precision ways to examine occlusal contacts and muscle function. Recently, two separate computer technologies have been synchronized together, so that an operator can record their separate diagnostic data simultaneously. The two systems are: the T Scan II Occlusal Analysis System and the Biopak Electromyography Recording System. The simultaneous recording and playback capacity of these two computer systems allows the operator to analyze and correlate specific occlusal moments to specific electromyographic changes that result from these occlusal moments. This synchronization provides unparalleled evidence of the effect occlusal contact arrangement has on muscle function. Therefore, the occlusal condition of an inserted dental prosthesis or the occlusal scheme of the natural teeth (before and after corrective occlusal adjustments) can be readily evaluated, documented, and quantified for both, quality of occlusal parameters and muscle activity and the responses to the quality of the occlusal condition. This article describes their synchronization and illustrates their use in performing precision occlusal adjustment procedures on two patients: one who demonstrates occlusal disharmony while exhibiting the signs and symptoms of chronic myofascial pain dysfunction syndrome, and the other who had extensive restorative work accomplished but exhibits occlusal discomfort post-operatively.
Immunocytochemical analysis of P2X2 in rat circumvallate taste buds.
Yang, Ruibiao; Montoya, Alana; Bond, Amanda; Walton, Jenna; Kinnamon, John C
2012-05-23
Our laboratory has shown that classical synapses and synaptic proteins are associated with Type III cells. Yet it is generally accepted that Type II cells transduce bitter, sweet and umami stimuli. No classical synapses, however, have been found associated with Type II cells. Recent studies indicate that the ionotropic purinergic receptors P2X2/P2X3 are present in rodent taste buds. Taste nerve processes express the ionotropic purinergic receptors (P2X2/P2X3). P2X2/P2X3(Dbl-/-) mice are not responsive to sweet, umami and bitter stimuli, and it has been proposed that ATP acts as a neurotransmitter in taste buds. The goal of the present study is to learn more about the nature of purinergic contacts in rat circumvallate taste buds by examining immunoreactivity to antisera directed against the purinergic receptor P2X2. P2X2-like immunoreactivity is present in intragemmal nerve processes in rat circumvallate taste buds. Intense immunoreactivity can also be seen in the subgemmal nerve plexuses located below the basal lamina. The P2X2 immunoreactive nerve processes also display syntaxin-1-LIR. The immunoreactive nerves are in close contact with the IP(3)R3-LIR Type II cells and syntaxin-1-LIR and/or 5-HT-LIR Type III cells. Taste cell synapses are observed only from Type III taste cells onto P2X2-LIR nerve processes. Unusually large, "atypical" mitochondria in the Type II taste cells are found only at close appositions with P2X2-LIR nerve processes. P2X2 immunogold particles are concentrated at the membranes of nerve processes at close appositions with taste cells. Based on our immunofluorescence and immunoelectron microscopical studies we believe that both perigemmal and most all intragemmal nerve processes display P2X2-LIR. Moreover, colloidal gold immunoelectron microscopy indicates that P2X2-LIR in nerve processes is concentrated at sites of close apposition with Type II cells. This supports the hypothesis that ATP may be a key neurotransmitter in taste transduction and that Type II cells release ATP, activating P2X2 receptors in nerve processes.
Mallet, Luc; Schüpbach, Michael; N'Diaye, Karim; Remy, Philippe; Bardinet, Eric; Czernecki, Virginie; Welter, Marie-Laure; Pelissolo, Antoine; Ruberg, Merle; Agid, Yves; Yelnik, Jérôme
2007-01-01
Two parkinsonian patients who experienced transient hypomanic states when the subthalamic nucleus (STN) was stimulated during postoperative adjustment of the electrical parameters for antiparkinsonian therapy agreed to have the mood disorder reproduced, in conjunction with motor, cognitive, and behavioral evaluations and concomitant functional neuroimaging. During the experiment, STN stimulation again induced a hypomanic state concomitant with activation of cortical and thalamic regions known to process limbic and associative information. This observation suggests that the STN plays a role in the control of a complex behavior that includes emotional as well as cognitive and motor components. The localization of the four contacts of the quadripolar electrode was determined precisely with an interactive brain atlas. The results showed that (i) the hypomanic state was caused only by stimulation through one contact localized in the anteromedial STN; (ii) both this contact and the contact immediately dorsal to it improved the parkinsonian motor state; (iii) the most dorsal and ventral contacts, located at the boundaries of the STN, neither induced the behavioral disorder nor improved motor performance. Detailed analysis of these data led us to consider a model in which the three functional modalities, emotional, cognitive, and motor, are not processed in a segregated manner but can be subtly combined in the small volume of the STN. This nucleus would thus serve as a nexus that integrates the motor, cognitive, and emotional components of behavior and might consequently be an effective target for the treatment of behavioral disorders that combine emotional, cognitive, and motor impairment. PMID:17556546
Dörken, H
1975-01-01
In Northern Germany (Schleswig-Holstein, Niedersachsen, Hamburg and Bremen) 140 children aged 2-14 years who had developed Hodgkin's disease after World War II were identified with the help of all 54 children's hospitals, the 101 local public health offices, and the Hamburg Cancer registry etc. Only histologically confirmed cases were included. For boys, comparison by urban and rural residence showed a preponderance of cases in rural areas (places with less than 2000 inhabitants). This urban-rural difference became statistically significant (P less than 0.05) when the cases reported from Hamburg (with its greater registration intensity) were excluded. For girls, there was no difference in the urban/rural distribution. Personal interviews were conducted with 133 case families. One third of the parents had been engaged in agricultural occupations. In the retrospective studies contacts with domestic animals was most impressive, especially those with rabbits (84.2%). But there was also contact with large animals, most frequently with pigs (45.9%). The difficulties of getting suitable controls--because of the widespread and changing keeping of animals--are discussed. A matched pair analysis of the 21 children from Hamburg confirmed significance (P less than 0.05) for contact with domestic rabbits.-- Furthermore, multiple cases (in family or in neighbourhood, "cluster") could mostly be linked together by contacts with the same herd. The epidemiological results from the basis of a hypothesis that Hodgkin's disease is a zoonosis. The possibility of a synergistic action of two factors--transmitted by two different species--is discussed.
Performance evaluation of a second-generation elastic loop mobility system
NASA Technical Reports Server (NTRS)
Melzer, K. J.; Swanson, G. D.
1974-01-01
Tests were conducted to evaluate the mobility performance of a second-generation Elastic Loop Mobility System (ELMS II). Performance on level test lanes and slopes of lunar soil simulant (LSS) and obstacle-surmounting and crevasse-crossing capabilities were investigated. In addition, internal losses and contact pressure distributions were evaluated. To evaluate the soft-soil performance, two basic soil conditions were tested: loose (LSS1) and dense (LSS5). These conditions embrace the spectrum of soil strengths tested during recent studies for NASA related to the mobility performance of the LRV. Data indicated that for the tested range of the various performance parameters, performance was independent of unit load (contact pressure) and ELMS II drum angular velocity, but was influenced by soil strength and ELMS pitch mode. Power requirements were smaller at a given system output for dense soil than for loose soil. The total system output in terms of pull developed or slope-climbing capability was larger for the ELMS II operating in restrained-pitch mode than in free-pitch mode.
Differential compaction behaviour of roller compacted granules of clopidogrel bisulphate polymorphs.
Khomane, Kailas S; Bansal, Arvind K
2014-09-10
In the present work, in-die and out-of-die compaction behaviour of dry-granulated powders of clopidogrel bisulphate (CLP) polymorphs, form I and form II, was investigated using a fully instrumented rotary tablet press. Each polymorph was compacted at three different roller pressures [70.3 (S1), 105.5 (S2) and 140.6 (S3)kgf/cm(2)], and obtained granules were characterized for their physico-mechanical properties. Compaction data were analyzed for out-of-die compressibility, tabletability and compactibility profiles, and in-die Heckel, Kawakita and Walker analysis. The roller compacted granules of both forms showed markedly different tabletting behaviour. Roller pressure exhibited a trend on compaction behaviour of form I granules, whereas, in case of form II, the effect was insignificant. Tabletability of the six granule batches follows the order; I_S1>I_S2>I_S3>II_S1≈II_S2≈II_S3. In case of form I, the reduced tabletability of the granules compacted at higher roller pressure was attributed to the decreased compressibility and plastic deformation. This was confirmed by compressibility plot and various mathematical parameters derived from Heckel (Py), Kawakita (1/b) and Walker (W) equations. The reduced tabletability of form I granules was due to 'granule hardening' during roller compaction. On the other hand, insignificant effect of roller compaction on tabletting behaviour of form II granules was attributed to brittle fragmentation. The extensive fragmentation of granules offered new 'clean' surfaces and higher contact points that negated the effect of granule hardening. Copyright © 2014 Elsevier B.V. All rights reserved.
NASA Astrophysics Data System (ADS)
Nakajo, Arata; Wuillemin, Zacharie; Van herle, Jan; Favrat, Daniel
Structural stability issues in planar solid oxide fuel cells arise from the mismatch between the coefficients of thermal expansion of the components. The stress state at operating temperature is the superposition of several contributions, which differ depending on the component. First, the cells accumulate residual stresses due to the sintering phase during the manufacturing process. Further, the load applied during assembly of the stack to ensure electric contact and flatten the cells prevents a completely stress-free expansion of each component during the heat-up. Finally, thermal gradients cause additional stresses in operation. The temperature profile generated by a thermo-electrochemical model implemented in an equation-oriented process modelling tool (gPROMS) was imported into finite-element software (ABAQUS) to calculate the distribution of stress and contact pressure on all components of a standard solid oxide fuel cell repeat unit. The different layers of the cell in exception of the cathode, i.e. anode, electrolyte and compensating layer were considered in the analysis to account for the cell curvature. Both steady-state and dynamic simulations were performed, with an emphasis on the cycling of the electrical load. The study includes two different types of cell, operation under both thermal partial oxidation and internal steam-methane reforming and two different initial thicknesses of the air and fuel compressive sealing gaskets. The results generated by the models are presented in two papers: Part I focuses on cell cracking. In the present paper, Part II, the occurrences of loss of gas-tightness in the compressive gaskets and/or electrical contact in the gas diffusion layer were identified. In addition, the dependence on temperature of both coefficients of thermal expansion and Young's modulus of the metallic interconnect (MIC) were implemented in the finite-element model to compute the plastic deformation, while the possibilities of thermal buckling were analysed in a dedicated and separate model. The value of the minimum stable thickness of the MIC is large, even though significantly affected by the operating conditions. This phenomenon prevents any unconsidered decrease of the thickness to reduce the thermal inertia of the stack. Thermal gradients and the shape of the temperature profile during operation induce significant decreases of the contact pressure on the gaskets near the fuel manifold, at the inlet or outlet, depending on the flow configuration. On the contrary, the electrical contact was ensured independently of the operating point and history, even though plastic strain developed in the gas diffusion layer.
Gil, Antonio; Amiri, Mohammad Javad; Abedi-Koupai, Jahangir; Eslamian, Saeid
2018-01-01
In this research, a versatile and highly efficient method for the stabilization of nanoscale zerovalent iron particles (nZVI) on the surface of ostrich bone ash (OBA) was presented as a novel inorganic adsorbent (OBA/nZVI) for the removal of Hg(II) and Pb(II) ions from aqueous solutions, even after 1 year of storage under room conditions. The removal behavior of the OBA/nZVI was assessed as a function of the initial pH, contact time, initial pollutants concentration, temperature, amount of adsorbent, effect of competitive metal ions, and ionic strength. The synthesized adsorbent was characterized by several techniques including N 2 adsorption at - 196 °C, FT-IR spectroscopy, scanning electron microscopy, X-ray diffraction, and zeta potential. The results confirmed that the OBA is a good candidate as support of nZVI. The maxima adsorption capacity for Hg(II) and Pb(II) ions found from experimental results were 170 and 160 mg g -1 , when the loading quantities of Fe were 20%. The equilibrium sorption data obeyed a Langmuir-Freundlich isotherm type model. The kinetic data of the adsorption followed the mechanism of the pseudo-second-order model. The thermodynamic experiments indicated that the removal of metal ions were feasible, endothermic, and spontaneous. It can be found that fresh and aged OBA/nZVI maintained its usability even after five cycles in the order: fresh (OBA/nZVI)-Hg(II) > fresh (OBA/nZVI)-Pb(II) > aged (OBA/nZVI)-Hg(II) > aged (OBA/nZVI)-Pb(II), which indicate that OBA/nZVI can be regenerated as adsorbent. The existence of Fe in the OBA/nZVI was proved by SEM-EDX results and X-ray diffraction analysis also confirmed adsorption/reduction of some of the Hg(II) to Hg 0 and Pb(II) to Pb 0 .
Fan, Mingyi; Hu, Jiwei; Cao, Rensheng; Xiong, Kangning; Wei, Xionghui
2017-12-21
Reduced graphene oxide-supported nanoscale zero-valent iron (nZVI/rGO) magnetic nanocomposites were prepared and then applied in the Cu(II) removal from aqueous solutions. Scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy and superconduction quantum interference device magnetometer were performed to characterize the nZVI/rGO nanocomposites. In order to reduce the number of experiments and the economic cost, response surface methodology (RSM) combined with artificial intelligence (AI) techniques, such as artificial neural network (ANN), genetic algorithm (GA) and particle swarm optimization (PSO), has been utilized as a major tool that can model and optimize the removal processes, because a tremendous advance has recently been made on AI that may result in extensive applications. Based on RSM, ANN-GA and ANN-PSO were employed to model the Cu(II) removal process and optimize the operating parameters, e.g., operating temperature, initial pH, initial concentration and contact time. The ANN-PSO model was proven to be an effective tool for modeling and optimizing the Cu(II) removal with a low absolute error and a high removal efficiency. Furthermore, the isotherm, kinetic, thermodynamic studies and the XPS analysis were performed to explore the mechanisms of Cu(II) removal process.
Adsorption of heavy metals from aqueous solutions by Mg-Al-Zn mingled oxides adsorbent.
El-Sayed, Mona; Eshaq, Gh; ElMetwally, A E
2016-10-01
In our study, Mg-Al-Zn mingled oxides were prepared by the co-precipitation method. The structure, composition, morphology and thermal stability of the synthesized Mg-Al-Zn mingled oxides were analyzed by powder X-ray diffraction, Fourier transform infrared spectrometry, N 2 physisorption, scanning electron microscopy, differential scanning calorimetry and thermogravimetry. Batch experiments were performed to study the adsorption behavior of cobalt(II) and nickel(II) as a function of pH, contact time, initial metal ion concentration, and adsorbent dose. The maximum adsorption capacity of Mg-Al-Zn mingled oxides for cobalt and nickel metal ions was 116.7 mg g -1 , and 70.4 mg g -1 , respectively. The experimental data were analyzed using pseudo-first- and pseudo-second-order kinetic models in linear and nonlinear regression analysis. The kinetic studies showed that the adsorption process could be described by the pseudo-second-order kinetic model. Experimental equilibrium data were well represented by Langmuir and Freundlich isotherm models. Also, the maximum monolayer capacity, q max , obtained was 113.8 mg g -1 , and 79.4 mg g -1 for Co(II), and Ni(II), respectively. Our results showed that Mg-Al-Zn mingled oxides can be used as an efficient adsorbent material for removal of heavy metals from industrial wastewater samples.
Identification of Microorganisms Isolated From Counterfeit and Unapproved Decorative Contact Lenses.
Land, Adrian D; Penno, Katie L; Brzezinski, Jennifer L
2018-03-01
All contact lenses (corrective/noncorrective) are considered Class II or Class III medical devices under the Federal Food, Drug, and Cosmetic Act, which also states that contact lenses can only be obtained with a prescription. The Forensic Chemistry Center of the US Food & Drug Administration has examined over 300 decorative, noncorrective contact lenses obtained without a prescription. Our observations indicate that 60% of the counterfeit lenses and 27% of the unapproved lenses examined were positive for microbial contamination. Twenty-nine different brands of noncorrective contact lenses were examined, and 48% of them had at least one sample positive for microbial contamination. Each microorganism was further identified using DNA sequencing. Contaminated contact lenses are associated with numerous health risks, including ocular infections and conjunctivitis leading to permanent visual impairment or blindness. These results support the contention that acquiring contact lenses without a prescription is a considerable threat to consumer health and safety. Published 2017. This article is a U.S. Government work and is in the public domain in the USA.
Removal of Pb(II) and Cd(II) from water by adsorption on peels of banana.
Anwar, Jamil; Shafique, Umer; Waheed-uz-Zaman; Salman, Muhammad; Dar, Amara; Anwar, Shafique
2010-03-01
The adsorption of lead(II) and cadmium(II) on peels of banana has been studied in batch mode using flame atomic absorption spectroscopy for metal estimation. Concerned parameters like adsorbent dose, pH, contact time and agitation speed were investigated. Langmuir, Freundlich and Temkin isotherms were employed to describe adsorption equilibrium. The maximum amounts of cadmium(II) and lead(II) adsorbed (qm), as evaluated by Langmuir isotherm, were 5.71 mg and 2.18 mg per gram of powder of banana peels, respectively. Study concluded that banana peels, a waste material, have good potential as an adsorbent to remove toxic metals like lead and cadmium from water. Copyright (c) 2009 Elsevier Ltd. All rights reserved.
Code of Federal Regulations, 2014 CFR
2014-07-01
... chapter (Bureau of Mines Schedule 2G). (e) Electrical contact shall be maintained between the mine track...)(i) Except as provided in paragraph (f)(1)(ii) of this section electric power shall be supplied to... transported. (ii) Where direct current electric power is used and such electric power can be supplied only...
Code of Federal Regulations, 2013 CFR
2013-07-01
... chapter (Bureau of Mines Schedule 2G). (e) Electrical contact shall be maintained between the mine track...)(i) Except as provided in paragraph (f)(1)(ii) of this section electric power shall be supplied to... transported. (ii) Where direct current electric power is used and such electric power can be supplied only...
Code of Federal Regulations, 2012 CFR
2012-07-01
... chapter (Bureau of Mines Schedule 2G). (e) Electrical contact shall be maintained between the mine track...)(i) Except as provided in paragraph (f)(1)(ii) of this section electric power shall be supplied to... transported. (ii) Where direct current electric power is used and such electric power can be supplied only...
Code of Federal Regulations, 2010 CFR
2010-07-01
... chapter (Bureau of Mines Schedule 2G). (e) Electrical contact shall be maintained between the mine track...)(i) Except as provided in paragraph (f)(1)(ii) of this section electric power shall be supplied to... transported. (ii) Where direct current electric power is used and such electric power can be supplied only...
Code of Federal Regulations, 2011 CFR
2011-07-01
... chapter (Bureau of Mines Schedule 2G). (e) Electrical contact shall be maintained between the mine track...)(i) Except as provided in paragraph (f)(1)(ii) of this section electric power shall be supplied to... transported. (ii) Where direct current electric power is used and such electric power can be supplied only...
Experimental study of Pb (II) solution sorption behavior onto Coffee Husk Bioactivated Carbon
NASA Astrophysics Data System (ADS)
Fona, Z.; Habibah, U.
2018-04-01
Coffee husk which is abundantly produced in the coffee plantations is potential to be a challenging adsorbent. The fate of Pb (II) solution in the sorption mechanism onto the adsorbent has been investigated. This paper aimed to study the efficiency of Pb (II) aqueous solution removal using activated carbon from coffee husk (CAC). The sorption characteristics were using two isotherm models, Langmuir and Freundlich, were also reported. The coffee husk from local plantations in Middle Aceh was carbonized and sieved to 120/140 mesh. The charcoal was activated using hydrochloric acid before contacted with the different initial concentrations of Pb (II) solution. The remaining concentrations of the metal in the specified contact times were determined using Atomic Adsorption Spectrophotometer at 283.3 wavelength. The result showed that the equilibrium concentrations were obtained in about 30 minutes which depended on the initial concentration. The sorption mechanism followed Freundlich isotherm model where the adsorption constant and capacity were accordingly 1.353 and 1.195 mgg‑1. The iodine sorption was up to 1,053 mgg‑1. Based on the ash and moisture content, as well as iodine sorption, the activated carbon met the national standard.
Dynamics of myosin II organization into cortical contractile networks and fibers
NASA Astrophysics Data System (ADS)
Nie, Wei; Wei, Ming-Tzo; Ou-Yang, Daniel; Jedlicka, Sabrina; Vavylonis, Dimitrios
2014-03-01
The morphology of adhered cells critically depends on the formation of a contractile meshwork of parallel and cross-linked stress fibers along the contacting surface. The motor activity and mini-filament assembly of non-muscle myosin II is an important component of cell-level cytoskeletal remodeling during mechanosensing. To monitor the dynamics of myosin II, we used confocal microscopy to image cultured HeLa cells that stably express myosin regulatory light chain tagged with GFP (MRLC-GFP). MRLC-GFP was monitored in time-lapse movies at steady state and during the response of cells to varying concentrations of blebbistatin which disrupts actomyosin stress fibers. Using image correlation spectroscopy analysis, we quantified the kinetics of disassembly and reassembly of actomyosin networks and compared them to studies by other groups. This analysis suggested that the following processes contribute to the assembly of cortical actomyosin into fibers: random myosin mini-filament assembly and disassembly along the cortex; myosin mini-filament aligning and contraction; stabilization of cortical myosin upon increasing contractile tension. We developed simple numerical simulations that include those processes. The results of simulations of cells at steady state and in response to blebbistatin capture some of the main features observed in the experiments. This study provides a framework to help interpret how different cortical myosin remodeling kinetics may contribute to different cell shape and rigidity depending on substrate stiffness.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Boparai, Hardiljeet K.; Comfort, Steve; Satapanajaru, Tunlawit
Zerovalent iron barriers have become a viable treatment for field-scale cleanup of various ground water contaminants. While contact with the iron surface is important for contaminant destruction, the interstitial pore water within and near the iron barrier will be laden with aqueous, adsorbed and precipitated FeII phases. These freshly precipitated iron minerals could play an important role in transforming high explosives (HE). Our objective was to determine the transformation of RDX (hexahydro-1,3,5-trinitro-1,3,5-triazine), HMX (octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine), and TNT (2,4,6-trinitrotoluene) by freshly precipitated iron FeII/FeIII minerals. This was accomplished by quantifying the effects of initial FeII concentration, pH, and the presence of aquifermore » solids (FeIII phases) on HE transformation rates. Results showed that at pH 8.2, freshly precipitated iron minerals transformed RDX, HMX, and TNT with reaction rates increasing with increasing FeII concentrations. RDX and HMX transformations in these solutions also increased with increasing pH (5.8-8.55). By contrast, TNT transformation was not influenced by pH (6.85-8.55) except at pH values <6.35. Transformations observed via LC/MS included a variety of nitroso products (RDX, HMX) and amino degradation products (TNT). XRD analysis identified green rust and magnetite as the dominant iron solid phases that precipitated from the aqueous FeII during HE treatment under anaerobic conditions. Geochemical modeling also predicted FeII activity would likely be controlled by green rust and magnetite. These results illustrate the important role freshly precipitated FeII/FeIII minerals in aqueous FeII solutions play in the transformation of high explosives.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Weil, Matthias, E-mail: Matthias.Weil@tuwien.ac.at; Stöger, Berthold; Gierl-Mayer, Christian
2016-09-15
The compounds Ba[H{sub 4}TeO{sub 6}] (I), Ba[H{sub 2}TeO{sub 5}] (II), Ba[Te{sub 2}O{sub 6}(OH){sub 2}] (III) and Ba[TeO{sub 4}] (IV) were prepared by application of a diffusion method (I), under hydrothermal conditions (II and III) and from solid state reactions (IV), respectively. Structure analysis on the basis of single crystal X-ray diffraction data revealed novel structure types for (I), (II) and (III) and isotypism of (IV) with PrSbO{sub 4} and LaSbO{sub 4}. Common feature of the four oxotellurate(VI) structures are [TeO{sub 6}] octahedra. Whereas in the crystal structure of (I) the octahedral units are isolated, they are condensed into chains viamore » corner-sharing in (II) and via edge-sharing in (III) and (IV). The coordination numbers of the barium cations in the four structures range from seven to ten. Although hydrogen atom positions could not be located for the structures of (I) and (II), short interpolyhedral O···O contacts are evident for strong hydrogen bonding. The temperature behaviour of (I), (II) and (IV) was monitored by simultaneous thermal analysis (STA) measurements and in situ powder X-ray diffraction, revealing the decomposition sequence Ba[H{sub 4}TeO{sub 6}] → Ba[H{sub 2}TeO{sub 5}] → Ba[TeO{sub 4}]→ Ba[TeO{sub 3}] upon heating to temperatures up to 900 °C. - Graphical abstract: The crystal structures of the four oxotellurates(VI) were determined from single crystal data. The thermal decomposition of Ba[H{sub 4}TeO{sub 6}], monitored by temperature-dependent X-ray powder diffraction and simultaneous thermal analysis measurements, involves two condensation reactions according to Ba[H{sub 4}TeO{sub 6}]→Ba[H{sub 2}TeO{sub 5}]+H{sub 2}O(↑)→Ba[TeO{sub 4}]+ H{sub 2}O(↑). Display Omitted.« less
Gold--a controversial sensitizer. European Environmental and Contact Dermatitis Research Group.
Bruze, M; Andersen, K E
1999-06-01
Until recently, gold allergy was considered to be extremely rare. Gold has been used and worshipped for thousands of years without any obvious complaints of skin problems, either in those participating in mining and other ways of prospecting, or in those wearing jewellery. When studies on contact allergy to gold sodium thiosulfate were published at the beginning of the 1990s, the allergic nature of the reported positive patch test reactions to gold was questioned. The major argument for such questioning was the lack of demonstrable clinical relevance in most positive reactors. A major reason for the questioning may have been confusion in differentiating between contact allergy and allergic contact dermatitis. To arrive at a diagnosis of allergic contact dermatitis, 3 steps have, in principle, to be fulfilled: (i) establishment of contact allergy; (ii) demonstration of present exposure; (iii) assessment of clinical relevance, i.e., causing or aggravating a contact dermatitis. In this paper, these steps are discussed with regard to gold. With our present knowledge of contact allergy-allergic contact dermatitis, we do not recommend including gold sodium thiosulfate in the standard series. It should be applied for scientific purposes and when allergic contact dermatitis from gold is suspected.
NASA Astrophysics Data System (ADS)
Joo, Hyun S.; Seo, Dong C.; Kim, Chang M.; Lim, Young T.; Cho, Seong D.; Lee, Jong B.; Song, Ji Y.; Kim, Kyoung M.; Park, Joo H.; Jung, Jae Chang; Shin, Ki S.; Bok, Cheol Kyu; Moon, Seung C.
2004-05-01
There are numerous methods being explored by lithographers to achieve the patterning of sub-90nm contact hole features. Regarding optical impact on contact imaging, various optical extension techniques such as assist features, focus drilling, phase shift masks, and off-axis illumination are being employed to improve the aerial image. One possible option for improving of the process window in contact hole patterning is resist reflow. We have already reported the resist using a ring opened polymer of maleic anhydride unit(ROMA) during the past two years in this conference. It has several good properties such as UV transmittance, PED stability, solubility and storage stability. The resist using ROMA polymer as a matrix resin showed a good lithographic performance at C/H pattern and one of the best characteristics in a ROMA polymer is the property of thermal shrinkage. It has a specific glass transition temperature(Tg) each polymers, so they made a applying of resist reflow technique to print sub-90nm C/H possible. Recently, we have researched about advanced ROMA polymer(ROMA II), which is composed of cycloolefine derivatives with existing ROMA type polymer(ROMA I), for dry etch resistance increasing, high resolution, and good thermal shrinkage property. In this paper, we will present the structure, thermal shrinkage properties, Tg control, material properties for ROMA II polymer and will show characteristics, the lithographic performance for iso and dense C/H applications of the resist using ROMA II polymer. In addition, we will discuss resist reflow data gained at C/H profile of sub-90nm sizes, which has good process window.
Method of manufacturing semiconductor having group II-group VI compounds doped with nitrogen
Compaan, Alvin D.; Price, Kent J.; Ma, Xianda; Makhratchev, Konstantin
2005-02-08
A method of making a semiconductor comprises depositing a group II-group VI compound onto a substrate in the presence of nitrogen using sputtering to produce a nitrogen-doped semiconductor. This method can be used for making a photovoltaic cell using sputtering to apply a back contact layer of group II-group VI compound to a substrate in the presence of nitrogen, the back coating layer being doped with nitrogen. A semiconductor comprising a group II-group VI compound doped with nitrogen, and a photovoltaic cell comprising a substrate on which is deposited a layer of a group II-group VI compound doped with nitrogen, are also included.
NASA Astrophysics Data System (ADS)
Zularisam, A. W.; Wahida, Norul
2017-07-01
Nickel (II) is one of the most toxic contaminants recognised as a carcinogenic and mutagenic agent which needs complete removal from wastewater before disposal. In the present study, a novel adsorbent called mesoparticle graphene sand composite (MGSCaps) was synthesised from arenga palm sugar and sand by using a green, simple, low cost and efficient methodology. Subsequently, this composite was characterised and identified using field emission scanning electron microscope (FESEM), x-ray diffraction (XRD) and elemental mapping (EM). The adsorption process was investigated and optimised under the experimental parameters such as pH, contact time and bed depth. The results showed that the interaction between nickel (II) and MGSCaps was not ion to ion interaction hence removal of Ni (II) can be applied at any pH. The results were also exhibited the higher contact time and bed depth, the higher removal percentage of nickel (II) occurred. Adsorption kinetic data were modelled using Pseudo-first-order and Pseudo-second-order equation models. The experimental results indicated pseudo-second-order kinetic equation was most suitable to describe the experimental adsorption kinetics data with maximum capacity of 40% nickel (II) removal for the first hour. The equilibrium adsorption data was fitted with Langmuir, and Freundlich isotherms equations. The data suggested that the most fitted equation model is the Freundlich with correlation R2=0.9974. Based on the obtained results, it can be stated that the adsorption method using MGSCaps is an efficient, facile and reliable method for the removal of nickel (II) from waste water.
Method For Creating Corrosion Resistant Surface On An Aluminum Copper Alloy
Mansfeld, Florian B.; Wang, You; Lin, Simon H.
1997-06-03
A method for treating the surface of aluminum alloys hang a relatively high copper content is provided which includes the steps of removing substantially all of the copper from the surface, contacting the surface with a first solution containing cerium, electrically charging the surface while contacting the surface in an aqueous molybdate solution, and contacting the surface with a second solution containing cerium. The copper is substantially removed from the surface in the first step either by (i) contacting the surface with an acidic chromate solution or by (ii) contacting the surface with an acidic nitrate solution while subjecting the surface to an electric potential. The corrosion-resistant surface resulting from the invention is excellent, consistent and uniform throughout the surface. Surfaces treated by the invention may often be certified for use in salt-water services.
Li, Xiaona; Li, Airong; Long, Mingzhong; Tian, Xingjun
2015-01-01
Ceriporia lacerata, a strain of white-rot fungus isolated from the litter of an invasive plant (Solidago canadensis) in China, was little known about its properties and utilization. In this work, the copper(II) biosorption characteristics of formaldehyde inactivated C. lacerata biomass were examined as a function of initial pH, initial copper(II) concentration and contact time, and the adsorptive equilibrium and kinetics were simulated, too. The optimum pH was found to be 6.0 at experimental conditions of initial copper(II) concentration 100 mg/L, biomass dose 2 g/L, contact time 12 h, shaking rate 150 r/min and temperature 25°C. Biosorption equilibrium cost about 1 hour at experimental conditions of pH 6.0, initial copper(II) concentration 100 mg/L, C. lacerata dose 2 g/L, shaking rate 150 r/min and temperature 25°C. At optimum pH 6.0, highest copper(II) biosorption amounts were 6.79 and 7.76 mg/g for initial copper(II) concentration of 100 and 200 mg/L, respectively (with other experimental parameters of C. lacerata dose 2 g/L, shaking rate 150 r/min and temperature 25°C). The pseudo second-order adsorptive model gave the best adjustment for copper(II) biosorption kinetics. The equilibrium data fitted very well to both Langmuir and Freundlich adsorptive isotherm models. Without further acid or alkali treatment for improving adsorption properties, formaldehyde inactivated C. lacerata biomass possesses good biosorption characteristics on copper(II) removal from aqueous solutions.
Fan, Mingyi; Li, Tongjun; Hu, Jiwei; Cao, Rensheng; Wu, Qing; Wei, Xionghui; Li, Lingyun; Shi, Xuedan; Ruan, Wenqian
2016-01-01
Reduced graphene oxide-supported nanoscale zero-valent iron (nZVI/rGO) composites were prepared by chemical deposition method and were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), Raman spectroscopy, N2-sorption and X-ray photoelectron spectroscopy (XPS). Operating parameters for the removal process of Pb(II) ions, such as temperature (20–40 °C), pH (3–5), initial concentration (400–600 mg/L) and contact time (20–60 min), were optimized using a quadratic model. The coefficient of determination (R2 > 0.99) obtained for the mathematical model indicates a high correlation between the experimental and predicted values. The optimal temperature, pH, initial concentration and contact time for Pb(II) ions removal in the present experiment were 21.30 °C, 5.00, 400.00 mg/L and 60.00 min, respectively. In addition, the Pb(II) removal by nZVI/rGO composites was quantitatively evaluated by using adsorption isotherms, such as Langmuir and Freundlich isotherm models, of which Langmuir isotherm gave a better correlation, and the calculated maximum adsorption capacity was 910 mg/g. The removal process of Pb(II) ions could be completed within 50 min, which was well described by the pseudo-second order kinetic model. Therefore, the nZVI/rGO composites are suitable as efficient materials for the advanced treatment of Pb(II)-containing wastewater. PMID:28773813
Fan, Mingyi; Li, Tongjun; Hu, Jiwei; Cao, Rensheng; Wu, Qing; Wei, Xionghui; Li, Lingyun; Shi, Xuedan; Ruan, Wenqian
2016-08-12
Reduced graphene oxide-supported nanoscale zero-valent iron (nZVI/rGO) composites were prepared by chemical deposition method and were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), Raman spectroscopy, N₂-sorption and X-ray photoelectron spectroscopy (XPS). Operating parameters for the removal process of Pb(II) ions, such as temperature (20-40 °C), pH (3-5), initial concentration (400-600 mg/L) and contact time (20-60 min), were optimized using a quadratic model. The coefficient of determination ( R ² > 0.99) obtained for the mathematical model indicates a high correlation between the experimental and predicted values. The optimal temperature, pH, initial concentration and contact time for Pb(II) ions removal in the present experiment were 21.30 °C, 5.00, 400.00 mg/L and 60.00 min, respectively. In addition, the Pb(II) removal by nZVI/rGO composites was quantitatively evaluated by using adsorption isotherms, such as Langmuir and Freundlich isotherm models, of which Langmuir isotherm gave a better correlation, and the calculated maximum adsorption capacity was 910 mg/g. The removal process of Pb(II) ions could be completed within 50 min, which was well described by the pseudo-second order kinetic model. Therefore, the nZVI/rGO composites are suitable as efficient materials for the advanced treatment of Pb(II)-containing wastewater.
Towards an optimal contact metal for CNTFETs.
Fediai, Artem; Ryndyk, Dmitry A; Seifert, Gotthard; Mothes, Sven; Claus, Martin; Schröter, Michael; Cuniberti, Gianaurelio
2016-05-21
Downscaling of the contact length Lc of a side-contacted carbon nanotube field-effect transistor (CNTFET) is challenging because of the rapidly increasing contact resistance as Lc falls below 20-50 nm. If in agreement with existing experimental results, theoretical work might answer the question, which metals yield the lowest CNT-metal contact resistance and what physical mechanisms govern the geometry dependence of the contact resistance. However, at the scale of 10 nm, parameter-free models of electron transport become computationally prohibitively expensive. In our work we used a dedicated combination of the Green function formalism and density functional theory to perform an overall ab initio simulation of extended CNT-metal contacts of an arbitrary length (including infinite), a previously not achievable level of simulations. We provide a systematic and comprehensive discussion of metal-CNT contact properties as a function of the metal type and the contact length. We have found and been able to explain very uncommon relations between chemical, physical and electrical properties observed in CNT-metal contacts. The calculated electrical characteristics are in reasonable quantitative agreement and exhibit similar trends as the latest experimental data in terms of: (i) contact resistance for Lc = ∞, (ii) scaling of contact resistance Rc(Lc); (iii) metal-defined polarity of a CNTFET. Our results can guide technology development and contact material selection for downscaling the length of side-contacts below 10 nm.
Interpretation of In situ Testing of Cohesive Soils Using Rational Methods
1990-11-01
a circular steel diaphragm located on the flat face of the device. Section 5 describes a comprehensive analysis of the contact pressure for...9o II Z * 0~ 00 0 o- V 0 - V ( Cl c~0 114 U+ e 0 00 0 cn 0 - t 00 r- UI en tn m i > 0 3 115 WATER SEAL- SOIL SEAL UFRICTION SLEEVE BEARING LOAD CELL...difference with OCR (Sully et al., 1987) 127 5 0 1.0/F IV / r 4 Intact M50 0.4 0j 1 0 1 05 0 OCR * Figure 4.1 a Correlation of pore pressure ratio with OCR
75 FR 69620 - Humboldt Resource Advisory Committee (RAC)
Federal Register 2010, 2011, 2012, 2013, 2014
2010-11-15
... INFORMATION CONTACT: Adam Dellinger, Committee Coordinator, at (707) 441-3569; e-mail [email protected] II project submissions, voting process for recommendation of project funding, and public comment...
Chan, Eunice HoYee; Chavadimane Shivakumar, Pruthvi; Clément, Raphaël; Laugier, Edith; Lenne, Pierre-François
2017-01-01
Adhesion molecules hold cells together but also couple cell membranes to a contractile actomyosin network, which limits the expansion of cell contacts. Despite their fundamental role in tissue morphogenesis and tissue homeostasis, how adhesion molecules control cell shapes and cell patterns in tissues remains unclear. Here we address this question in vivo using the Drosophila eye. We show that cone cell shapes depend little on adhesion bonds and mostly on contractile forces. However, N-cadherin has an indirect control on cell shape. At homotypic contacts, junctional N-cadherin bonds downregulate Myosin-II contractility. At heterotypic contacts with E-cadherin, unbound N-cadherin induces an asymmetric accumulation of Myosin-II, which leads to a highly contractile cell interface. Such differential regulation of contractility is essential for morphogenesis as loss of N-cadherin disrupts cell rearrangements. Our results establish a quantitative link between adhesion and contractility and reveal an unprecedented role of N-cadherin on cell shapes and cell arrangements. DOI: http://dx.doi.org/10.7554/eLife.22796.001 PMID:28537220
All-vapor processing of p-type tellurium-containing II-VI semiconductor and ohmic contacts thereof
McCandless, Brian E.
2001-06-26
An all dry method for producing solar cells is provided comprising first heat-annealing a II-VI semiconductor; enhancing the conductivity and grain size of the annealed layer; modifying the surface and depositing a tellurium layer onto the enhanced layer; and then depositing copper onto the tellurium layer so as to produce a copper tellurium compound on the layer.
Elastic stability of DNA configurations. II. Supercoiled plasmids with self-contact
NASA Astrophysics Data System (ADS)
Coleman, Bernard D.; Swigon, David; Tobias, Irwin
2000-01-01
Configurations of protein-free DNA miniplasmids are calculated with the effects of impenetrability and self-contact forces taken into account by using exact solutions of Kirchhoff's equations of equilibrium for elastic rods of circular cross section. Bifurcation diagrams are presented as graphs of excess link, ΔL, versus writhe, W, and the stability criteria derived in paper I of this series are employed in a search for regions of such diagrams that correspond to configurations that are stable, in the sense that they give local minima to elastic energy. Primary bifurcation branches that originate at circular configurations are composed of configurations with Dm symmetry (m=2,3,...). Among the results obtained are the following. (i) There are configurations with C2 symmetry forming secondary bifurcation branches which emerge from the primary branch with m=3, and bifurcation of such secondary branches gives rise to tertiary branches of configurations without symmetry. (ii) Whether or not self-contact occurs, a noncircular configuration in the primary branch with m=2, called branch α, is stable when for it the derivative dΔL/dW, computed along that branch, is strictly positive. (iii) For configurations not in α, the condition dΔL/dW>0 is not sufficient for stability; in fact, each nonplanar contact-free configuration that is in a branch other than α is unstable. A rule relating the number of points of self-contact and the occurrence of intervals of such contact to the magnitude of ΔL, which in paper I was found to hold for segments of DNA subject to strong anchoring end conditions, is here observed to hold for computed configurations of protein-free miniplasmids.
Tuberculin skin testing: determinants and reaction.
Lao, L Y; De Guia, T
1999-09-01
Mantoux purified protein derivative (PPD) skin testing was performed in schoolchildren who were grouped according to positive (Group I, n = 205) and negative (Group II, n = 79) exposure to recent acid-fast bacilli (AFB) smear-positive tuberculosis (TB) family contact. A prospective case-control study was undertaken to evaluate whether repeat bacille Calmette-Guérin (BCG) vaccination, nutritional state, presence/absence of BCG scar, and degree of AFB positivity of sputum of adult TB cases affect PPD skin reactivity in these two groups. Group I with TB contacts had larger induration (13.00 +/- 11.29 mm) than the Group II control group of 4.52 +/- 6.20; P = 0.000. Purified protein derivative reaction as to the number of BCG vaccination(s) received showed an increase in size as the BCG vaccination is repeated with significantly larger induration in Group I than in Group II (P = 0.048). The nutritional status was subgrouped into A (weight < 10 percentile), B (weight 50-75 percentile), and C (weight > 90 percentile), which were comparable for both groups. The mean PPD induration of subgroup A in Groups I and II was not statistically different. However, the mean PPD induration was highly significant between Groups I and II in subgroup B (12.46 +/- 10.70 vs 3.80 +/- 5.71 mm; P = 0.000) and subgroup C (14.31 +/- 11.54 vs 5.42 +/- 6.70 mm; P = 0.000). Children in group I with the BCG scar were noted to have significantly greater PPD induration size than in group II (14.14 +/- 11.23 vs 5.05 +/- 6.24 mm; P = 0.000). The degree of AFB positivity of sputum of TB adult cases (1+ to 4+ and cavitary TB) has no effect on PPD size (P = 0.766). Close contact with individuals with active TB (AFB smear positive) is a very important factor for PPD skin conversion. Repeat BCG vaccination, malnutrition, and BCG with scars present difficulties in making a diagnosis of TB infection but did not affect PPD reactivity and did highlight the need for thorough clinical evaluation.
40 CFR 721.2077 - Substituted carbazate (generic).
Code of Federal Regulations, 2011 CFR
2011-07-01
... death. This concern is particularly true with respect to direct contact to the eyes. Exposure to the eyes may cause severe acute toxicity including death. (ii) Industrial, commercial, and consumer...
40 CFR 721.2077 - Substituted carbazate (generic).
Code of Federal Regulations, 2010 CFR
2010-07-01
... death. This concern is particularly true with respect to direct contact to the eyes. Exposure to the eyes may cause severe acute toxicity including death. (ii) Industrial, commercial, and consumer...
11 CFR 9039.3 - Examination and audits; investigations.
Code of Federal Regulations, 2011 CFR
2011-01-01
... books and records; (ii) Field interviews of agents and representatives of the candidate and his or her...; (iv) Verification of disbursement information by contacting reported vendors; (v) Written questions...
Metal regeneration of iron chelates in nitric oxide scrubbing
Chang, Shih-Ger; Littlejohn, David; Shi, Yao
1997-08-19
The present invention relates to a process of using metal particles to reduce NO to NH.sub.3. More specifically, the invention concerns an improved process to regenerate iron (II) (CHELATE) by reduction of iron (II) (CHELATE) (NO) complex, which process comprises: a) contacting an aqueous solution containing iron (II) (CHELATE) (NO) with metal particles at between about 20.degree. and 90.degree. C. to reduce NO present, produce ammonia or an ammonium ion, and produce free iron (II) (CHELATE) at a pH of between about 3 and 8. The process is useful to remove NO from flue gas and reduce pollution.
Metal regeneration of iron chelates in nitric oxide scrubbing
Chang, S.G.; Littlejohn, D.; Shi, Y.
1997-08-19
The present invention relates to a process of using metal particles to reduce NO to NH{sub 3}. More specifically, the invention concerns an improved process to regenerate iron (II) (CHELATE) by reduction of iron (II) (CHELATE) (NO) complex, which process comprises: (a) contacting an aqueous solution containing iron (II) (CHELATE) (NO) with metal particles at between about 20 and 90 C to reduce NO present, produce ammonia or an ammonium ion, and produce free iron (II) (CHELATE) at a pH of between about 3 and 8. The process is useful to remove NO from flue gas and reduce pollution. 34 figs.
The immunity-related GTPase Irga6 dimerizes in a parallel head-to-head fashion.
Schulte, Kathrin; Pawlowski, Nikolaus; Faelber, Katja; Fröhlich, Chris; Howard, Jonathan; Daumke, Oliver
2016-03-02
The immunity-related GTPases (IRGs) constitute a powerful cell-autonomous resistance system against several intracellular pathogens. Irga6 is a dynamin-like protein that oligomerizes at the parasitophorous vacuolar membrane (PVM) of Toxoplasma gondii leading to its vesiculation. Based on a previous biochemical analysis, it has been proposed that the GTPase domains of Irga6 dimerize in an antiparallel fashion during oligomerization. We determined the crystal structure of an oligomerization-impaired Irga6 mutant bound to a non-hydrolyzable GTP analog. Contrary to the previous model, the structure shows that the GTPase domains dimerize in a parallel fashion. The nucleotides in the center of the interface participate in dimerization by forming symmetric contacts with each other and with the switch I region of the opposing Irga6 molecule. The latter contact appears to activate GTP hydrolysis by stabilizing the position of the catalytic glutamate 106 in switch I close to the active site. Further dimerization contacts involve switch II, the G4 helix and the trans stabilizing loop. The Irga6 structure features a parallel GTPase domain dimer, which appears to be a unifying feature of all dynamin and septin superfamily members. This study contributes important insights into the assembly and catalytic mechanisms of IRG proteins as prerequisite to understand their anti-microbial action.
NASA Astrophysics Data System (ADS)
Castelain, Mickaël; Pignon, Frédéric; Piau, Jean-Michel; Magnin, Albert
2008-04-01
We used an optical tweezer to investigate the adhesion of yeast Saccharomyces cerevisiae onto a glass substrate at the initial contact. Micromanipulation of free-living objects with single-beam gradient optical trap enabled to highlight mechanisms involved in this initial contact. As a function of the ionic strength and with a displacement parallel to the glass surface, the yeast adheres following different successive ways: (i) Slipping and rolling at 1.5mM NaCl, (ii) slipping, rolling, and sticking at 15mM NaCl, and (iii) only sticking at 150mM. These observations were numerous and reproducible. A kinetic evolution of these adhesion phenomena during yeast movement was clearly established. The nature, range, and relative intensity of forces involved in these different adhesion mechanisms have been worked out as a quantitative analysis from Derjaguin-Landau-Verwey-Overbeek (DLVO) and extended DLVO theories. Calculations show that the adhesion mechanisms observed and their affinity with ionic strength were mainly governed by the Lifshitz-van der Waals interaction forces and the electrical double-layer repulsion to which are added specific contact forces linked to "sticky" glycoprotein secretion, considered to be the main forces capable of overcoming the short-range Lewis acid-base repulsions.
49 CFR 830.5 - Immediate notification.
Code of Federal Regulations, 2010 CFR
2010-10-01
..., NTSB headquarters is located at 490 L'Enfant Plaza, SW., Washington, DC 20594. Contact information for... unit, or air-driven generator to retain flight control or essential instruments; (ii) In-flight failure...
The role of chitosan as nanofiller of graphite oxide for the removal of toxic mercury ions.
Kyzas, George Z; Travlou, Nikolina A; Deliyanni, Eleni A
2014-01-01
The present study focuses on the role of chitosan (CS) as nanofiller of graphite oxide (GO) in order to prepare composite materials with improved Hg(II) adsorption properties. The removal of Hg(II) from aqueous solutions was studied using adsorbents as graphite oxide (GO), graphite oxide nanofilled with chitosan (GO/CS) and magnetic chitosan (GO/mCS). Many possible interactions between materials and Hg(II) were observed after adsorption and explained via characterization with various techniques (SEM/EDAX, FTIR, XRD, DTG). The adsorption evaluation was done studying various parameters as the effect of pH (both in adsorption and desorption), contact time (pseudo-second order fitting), temperature (isotherms at 25, 45, 65 °C), in line with a brief thermodynamic analysis (ΔG(0), ΔH(0), ΔS(0)). The maximum adsorption capacity (fitting with Langmuir model) of GO at 25 °C was Qmax=187 mg/g, while after the CS nanofilling (formation of the composite GO/CS), Qmax was increased to 381 mg/g with a further enhancement for GO/mCS (Qmax=397 mg/g). Copyright © 2013 Elsevier B.V. All rights reserved.
Brun, Nadja Rebecca; Lenz, Markus; Wehrli, Bernhard; Fent, Karl
2014-04-01
The increasing use of zinc oxide nanoparticles (nZnO) and their associated environmental occurrence make it necessary to assess their potential effects on aquatic organisms. Upon water contact, nZnO dissolve partially to zinc (Zn(II)). To date it is not yet completely understood, whether effects of nZnO are solely or partly due to dissolved Zn(II). Here we compare potential effects of 0.2, 1 and 5mg/L nZnO and corresponding concentrations of released Zn(II) by water soluble ZnCl2 to two development stages of zebrafish, embryos and eleuthero-embryos, by analysing expressional changes by RT-qPCR. Another objective was to assess uptake and tissue distribution of Zn(II). Laser ablation-ICP-MS analysis demonstrated that uptake and tissue distribution of Zn(II) were identical for nZnO and ZnCl2 in eleuthero-embryos. Zn(II) was found particularly in the retina/pigment layer of eyes and brain. Both nZnO and dissolved Zn(II) derived from ZnCl2 had similar inhibiting effects on hatching, and they induced similar expressional changes of target genes. At 72hours post fertilization (hpf), both nZnO and Zn(II) delayed hatching at all doses, and inhibited hatching at 1 and 5 mg/L at 96 hpf. Both nZnO and Zn(II) lead to induction of metallothionein (mt2) in both embryos and eleuthero-embryos at all concentrations. Transcripts of oxidative stress related genes cat and Cu/Zn sod were also altered. Moreover, we show for the first time that nZnO exposure results in transcriptional changes of pro-inflammatory cytokines IL-1β and TNFα. Overall, transcriptional alterations were higher in embryos than eleuthero-embryos. The similarities of the effects lead to the conclusion that effects of nZnO are mainly related to the release of Zn(II). Copyright © 2014 Elsevier B.V. All rights reserved.
Kvetonova, Dana; Mynarova, Anna; Shutt, Kathryn A.; Pomajbikova, Katerina; Kalousova, Barbora; Modry, David; Benavides, Julio; Todd, Angelique; Kvac, Martin
2013-01-01
Background Infectious diseases pose one of the greatest threats to endangered species, and a risk of gastrointestinal parasite transmission from humans to wildlife has always been considered as a major concern of tourism. Increased anthropogenic impact on primate populations may result in general changes in communities of their parasites, and also in a direct exchange of parasites between humans and primates. Aims To evaluate the impact of close contact with humans on the occurrence of potentially zoonotic protists in great apes, we conducted a long-term monitoring of microsporidia, Cryptosporidium and Giardia infections in western lowland gorillas at different stages of the habituation process, humans, and other wildlife in Dzanga-Sangha Protected Areas in the Central African Republic. Results We detected Encephalitozoon cuniculi genotypes I and II (7.5%), Enterocytozoon bieneusi genotype D and three novel genotypes (gorilla 1–3) (4.0%), Giardia intestinalis subgroup A II (2.0%) and Cryptosporidium bovis (0.5%) in gorillas, whereas in humans we found only G. intestinalis subgroup A II (2.1%). In other wild and domestic animals we recorded E. cuniculi genotypes I and II (2.1%), G. intestinalis assemblage E (0.5%) and C. muris TS03 (0.5%). Conclusion Due to the non-specificity of E. cuniculi genotypes we conclude that detection of the exact source of E. cuniculi infection is problematic. As Giardia intestinalis was recorded primarily in gorilla groups with closer human contact, we suggest that human-gorilla transmission has occurred. We call attention to a potentially negative impact of habituation on selected pathogens which might occur as a result of the more frequent presence of humans in the vicinity of both gorillas under habituation and habituated gorillas, rather than as a consequence of the close contact with humans, which might be a more traditional assumption. We encourage to observe the sections concerning hygiene from the IUCN best practice guidelines for all sites where increased human-gorilla contact occurs. PMID:23951255
Sak, Bohumil; Petrzelkova, Klara J; Kvetonova, Dana; Mynarova, Anna; Shutt, Kathryn A; Pomajbikova, Katerina; Kalousova, Barbora; Modry, David; Benavides, Julio; Todd, Angelique; Kvac, Martin
2013-01-01
Infectious diseases pose one of the greatest threats to endangered species, and a risk of gastrointestinal parasite transmission from humans to wildlife has always been considered as a major concern of tourism. Increased anthropogenic impact on primate populations may result in general changes in communities of their parasites, and also in a direct exchange of parasites between humans and primates. To evaluate the impact of close contact with humans on the occurrence of potentially zoonotic protists in great apes, we conducted a long-term monitoring of microsporidia, Cryptosporidium and Giardia infections in western lowland gorillas at different stages of the habituation process, humans, and other wildlife in Dzanga-Sangha Protected Areas in the Central African Republic. We detected Encephalitozoon cuniculi genotypes I and II (7.5%), Enterocytozoon bieneusi genotype D and three novel genotypes (gorilla 1-3) (4.0%), Giardia intestinalis subgroup A II (2.0%) and Cryptosporidium bovis (0.5%) in gorillas, whereas in humans we found only G. intestinalis subgroup A II (2.1%). In other wild and domestic animals we recorded E. cuniculi genotypes I and II (2.1%), G. intestinalis assemblage E (0.5%) and C. muris TS03 (0.5%). Due to the non-specificity of E. cuniculi genotypes we conclude that detection of the exact source of E. cuniculi infection is problematic. As Giardia intestinalis was recorded primarily in gorilla groups with closer human contact, we suggest that human-gorilla transmission has occurred. We call attention to a potentially negative impact of habituation on selected pathogens which might occur as a result of the more frequent presence of humans in the vicinity of both gorillas under habituation and habituated gorillas, rather than as a consequence of the close contact with humans, which might be a more traditional assumption. We encourage to observe the sections concerning hygiene from the IUCN best practice guidelines for all sites where increased human-gorilla contact occurs.
Off-Line Quality Control In Integrated Circuit Fabrication Using Experimental Design
NASA Astrophysics Data System (ADS)
Phadke, M. S.; Kackar, R. N.; Speeney, D. V.; Grieco, M. J.
1987-04-01
Off-line quality control is a systematic method of optimizing production processes and product designs. It is widely used in Japan to produce high quality products at low cost. The method was introduced to us by Professor Genichi Taguchi who is a Deming-award winner and a former Director of the Japanese Academy of Quality. In this paper we will i) describe the off-line quality control method, and ii) document our efforts to optimize the process for forming contact windows in 3.5 Aim CMOS circuits fabricated in the Murray Hill Integrated Circuit Design Capability Laboratory. In the fabrication of integrated circuits it is critically important to produce contact windows of size very near the target dimension. Windows which are too small or too large lead to loss of yield. The off-line quality control method has improved both the process quality and productivity. The variance of the window size has been reduced by a factor of four. Also, processing time for window photolithography has been substantially reduced. The key steps of off-line quality control are: i) Identify important manipulatable process factors and their potential working levels. ii) Perform fractional factorial experiments on the process using orthogonal array designs. iii) Analyze the resulting data to determine the optimum operating levels of the factors. Both the process mean and the process variance are considered in this analysis. iv) Conduct an additional experiment to verify that the new factor levels indeed give an improvement.
In situ electronic probing of semiconducting nanowires in an electron microscope.
Fauske, V T; Erlbeck, M B; Huh, J; Kim, D C; Munshi, A M; Dheeraj, D L; Weman, H; Fimland, B O; Van Helvoort, A T J
2016-05-01
For the development of electronic nanoscale structures, feedback on its electronic properties is crucial, but challenging. Here, we present a comparison of various in situ methods for electronically probing single, p-doped GaAs nanowires inside a scanning electron microscope. The methods used include (i) directly probing individual as-grown nanowires with a sharp nano-manipulator, (ii) contacting dispersed nanowires with two metal contacts and (iii) contacting dispersed nanowires with four metal contacts. For the last two cases, we compare the results obtained using conventional ex situ litho-graphy contacting techniques and by in situ, direct-write electron beam induced deposition of a metal (Pt). The comparison shows that 2-probe measurements gives consistent results also with contacts made by electron beam induced deposition, but that for 4-probe, stray deposition can be a problem for shorter nanowires. This comparative study demonstrates that the preferred in situ method depends on the required throughput and reliability. © 2015 The Authors Journal of Microscopy © 2015 Royal Microscopical Society.
Diepgen, T L; Ofenloch, R; Bruze, M; Cazzaniga, S; Coenraads, P J; Elsner, P; Goncalo, M; Svensson, Å; Naldi, L
2015-12-01
Contact allergy to fragrances is assessed mostly in clinical populations of patients. Studies in the general population are scarce and vary in their methodology across countries. To determine the prevalence of fragrance contact allergy in the European general population and to assess the clinical relevance of positive patch test reactions to different fragrances. In five European countries (Germany, Italy, the Netherlands, Portugal and Sweden) a random sample from the general population aged 18-74 years was drawn. In total, 12 377 subjects were interviewed in this cross-sectional study and a random sample (n = 3119) was patch tested using the TRUE Test and Finn Chamber techniques. Patch test procedures were harmonized by mandatory training before the study and monitoring during the study. The highest prevalence for contact allergy of 2·6% [95% confidence interval (CI) 2·1-3·2] was found for fragrance mix (FM) I in petrolatum, with a high content of atranol and chloratranol, followed by 1·9% (95% CI 1·5-2·4) for FM II in petrolatum. The conservatively estimated prevalence of fragrance contact allergy was 1·9% (95% CI 1·5-2·5). This is defined as the existence of a positive patch test to FM I or FM II; any of their individual materials; Myroxylon pereirae; sesquiterpene lactones or 3- and 4-hydroxyisohexyl 3-cyclohexene carboxaldehyde that show clinical relevance, defined conservatively as lifetime avoidance of scented products and an itchy skin rash lasting > 3 days in a lifetime. Using the reported lifetime prevalence of any contact dermatitis instead of the lifetime prevalence of any itchy skin rash, the prevalence is 0·8% (95% CI 0·5-1·2). The prevalence rates of contact allergy to fragrances in women are about twice those in men. This study helps to identify targets for prevention of fragrance allergy. © 2015 British Association of Dermatologists.
NASA Astrophysics Data System (ADS)
Amini, Amirhossein; Homsy, G. M.
2017-04-01
Experiments on evaporating droplets on structured surfaces have shown that the contact line does not move with constant speed, but rather in a steplike "stick-slip" fashion. As a first step in understanding such behavior, we study the evaporation of a two-dimensional volatile liquid droplet on a nonplanar heated solid substrate with a moving contact line and fixed contact angle. The model for the flat case is adapted to include curved substrates, numerical solutions are achieved for various periodic and quasiperiodic substrate profiles, and the dynamics of the contact line and the apparent contact angle are studied. In contrast with our results for a flat substrate, for which the contact line recedes in a nearly constant speed, we observe that the contact line speed and position show significant time variation and that the contact line moves in an approximate steplike fashion on relatively steep substrates. For the simplest case of a periodic substrate, we find that the apparent contact angle is periodic in time. For doubly periodic substrates, we find that the apparent contact angle is periodic and that the problem exhibits a phase-locking behavior. For multimode quasiperiodic substrates, we find the contact line behavior to be temporally complex and not only limited to a stick-slip motion. In all cases, we find that the overall evaporation is increased relative to the flat substrate.
Elastohydrodynamic film thickness model for heavily loaded contacts
NASA Technical Reports Server (NTRS)
Loewenthal, S. H.; Parker, R. J.; Zaretsky, E. V.
1973-01-01
An empirical elastohydrodynamic (EHD) film thickness formula for predicting the minimum film thickness occurring within heavily loaded contacts (maximum Hertz stresses above 150,000 psi) was developed. The formula was based upon X-ray film thickness measurements made with synthetic paraffinic, fluorocarbon, Type II ester and polyphenyl ether fluids covering a wide range of test conditions. Comparisons were made between predictions from an isothermal EHD theory and the test data. The deduced relationship was found to adequately reflect the high-load dependence exhibited by the measured data. The effects of contact geometry, material and lubricant properties on the form of the empirical model are also discussed.
Interaction of the Human Contact System with Pathogens-An Update.
Oehmcke-Hecht, Sonja; Köhler, Juliane
2018-01-01
The name human contact system is related to its mode of action, as "contact" with artificial negatively charged surfaces triggers its activation. Today, it is generally believed that the contact system is an inflammatory response mechanism not only against artificial material but also against misfolded proteins and foreign organisms. Upon activation, the contact system is involved in at least two distinct (patho)physiologic processes: i . the trigger of the intrinsic coagulation via factor XI and ii . the cleavage of high molecular weight kininogen with release of bradykinin and antimicrobial peptides (AMPs). Bradykinin is involved in the regulation of inflammatory processes, vascular permeability, and blood pressure. Due to the release of AMPs, the contact system is regarded as a branch of the innate immune defense against microorganisms. There is an increasing list of pathogens that interact with contact factors, in addition to bacteria also fungi and viruses bind and activate the system. In spite of that, pathogens have developed their own mechanisms to activate the contact system, resulting in manipulation of this host immune response. In this up-to-date review, we summarize present research on the interaction of pathogens with the human contact system, focusing particularly on bacterial and viral mechanisms that trigger inflammation via contact system activation.
High-spin ribbons and antiferromagnetic ordering of a Mn(II)-biradical-Mn(II) complex.
Fatila, Elisabeth M; Clérac, Rodolphe; Rouzières, Mathieu; Soldatov, Dmitriy V; Jennings, Michael; Preuss, Kathryn E
2013-09-11
A binuclear metal coordination complex of the first thiazyl-based biradical ligand 1 is reported (1 = 4,6-bis(1,2,3,5-dithiadiazolyl)pyrimidine; hfac =1,1,1,5,5,5,-hexafluoroacetylacetonato-). The Mn(hfac)2-biradical-Mn(hfac)2 complex 2 is a rare example of a discrete, molecular species employing a neutral bridging biradical ligand. It is soluble in common organic solvents and can be easily sublimed as a crystalline solid. Complex 2 has a spin ground state of S(T) = 4 resulting from antiferromagnetic coupling between the S(birad) = 1 biradical bridging ligand and two S(Mn) = 5/2 Mn(II) ions. Electrostatic contacts between atoms with large spin density promote a ferromagnetic arrangement of the moments of neighboring complexes in ribbon-like arrays. Weak antiferromagnetic coupling between these high-spin ribbons stabilizes an ordered antiferromagnetic ground state below 4.5 K. This is an unusual example of magnetic ordering in a molecular metal-radical complex, wherein the electrostatic contacts that direct the crystal packing are also responsible for providing an efficient exchange coupling pathway between molecules.
30 CFR 7.86 - Test equipment and specifications.
Code of Federal Regulations, 2012 CFR
2012-07-01
...) Filters—F1, F2, F3, and F4; (ii) Flowmeters—FL1, FL2, FL3, FL4, FL5, FL6, and FL7; (iii) Upstream Gauges... equivalent results. The components are designated as follows— (i) Filters—F1, F2, F3, and F4; (ii) Flowmeters... exhaust pipe up to the filter holder, which are in contact with raw and diluted exhaust gas, shall be...
Sequestration of toxic Pb(II) ions by chemically treated rubber (Hevea brasiliensis) leaf powder.
Kamal, Megat Hanafiah Megat Ahmad; Azira, Wan Mat Khalir Wan Khaima; Kasmawati, Mohamed; Haslizaidi, Zakaria; Saime, Wan Ngah Wan
2010-01-01
Rubber leaf powder (an agricultural waste) was treated with potassium permanganate followed by sodium carbonate and its performance in the removal of Pb(II) ions from aqueous solution was evaluated. The interactions between Pb(II) ions and functional groups on the adsorbent surface were confirmed by Fourier transform infrared (FT-IR) spectroscopy, scanning electron microscopy (SEM) coupled with X-ray energy dispersive spectroscopy (EDX). The effects of several important parameters which can affect adsorption capacity such as pH, adsorbent dosage, initial lead concentration and contact time were studied. The optimum pH range for lead adsorption was 4-5. Even at very low adsorbent dosage of 0.02 g, almost 100% of Pb(II) ions (23 mg/L) could be removed. The adsorption capacity was also dependent on lead concentration and contact time, and relatively a short period of time (60-90 min) was required to reach equilibrium. The equilibrium data were analyzed with Langmuir, Freundlich and Dubinin-Radushkevich isotherms. Based on Langmuir model, the maximum adsorption capacity of lead was 95.3 mg/g. Three kinetic models including pseudo first-order, pseudo second-order and Boyd were used to analyze the lead adsorption process, and the results showed that the pseudo second-order fitted well with correlation coefficients greater than 0.99.
Prevalence of contact allergy in the general population in different European regions.
Diepgen, T L; Ofenloch, R F; Bruze, M; Bertuccio, P; Cazzaniga, S; Coenraads, P-J; Elsner, P; Goncalo, M; Svensson, Å; Naldi, L
2016-02-01
Population-based studies about contact allergy are scarce. To obtain reliable estimates of the prevalence of contact allergy in the general population in Europe. A cross-sectional study of a random sample from the general population, aged 18-74 years, in five different European countries (Sweden, the Netherlands, Germany, Italy and Portugal). In total, 12 377 subjects were interviewed and a random sample (n = 3119) patch tested to TRUE Test panels 1-3 and Fragrance Mix (FM) II, hydroxyisohexyl 3-cyclohexene carboxaldehyde (HICC) and sesquiterpene lactone mix. A positive patch test reaction is considered as contact allergy. In total, 27·0% [95% confidence interval (CI) 25·5-28·5] had at least one positive reaction to an allergen of the European baseline series, with a significantly higher prevalence in women than in men. The highest age-standardized prevalences (≥ 1%) were found for nickel (14·5%, 95% CI 13·2-15·8), thiomersal (5·0%, 95% CI 4·2-5·8), cobalt (2·2%, 95% CI 1·7-2·7), FM II (1·9%, 95% CI 1·5-2·5), FM I (1·8%, 95% CI 1·4-2·3), HICC (1·4%, 95% CI 1·0-1·9), p-tert-butylphenol formaldehyde resin (1·3%, 95% CI 0·9-1·7) and para-phenylenediamine (1·0%, 95% CI 0·6-1·3). Only nickel and thiomersal showed a statistically significantly different prevalence for contact allergy among the different European populations. Subjects reporting contact dermatitis in their lifetime (age-standardized prevalence 15·1%, 95% CI 13·8-16·3) had an increased risk for contact allergy (odds ratio 1·9, 95% CI 1·5-2·5). The risk of having a contact allergy was not increased in those with atopic dermatitis (prevalence 7·6%, 95% CI 6·7-8·6; odds ratio 1·0, 95% CI 0·7-1·4). Contact allergy to at least one allergen of the European baseline series was diagnosed in more than one-quarter of the general European population. Therefore measures to improve the primary prevention of contact allergy have to be enforced. © 2015 British Association of Dermatologists.
Effect of contact ratio on spur gear dynamic load
NASA Technical Reports Server (NTRS)
Liou, Chuen-Huei; Lin, Hsiang Hsi; Oswald, Fred B.; Townsend, Dennis P.
1992-01-01
A computer simulation is presented which shows how the gear contact ratio affects the dynamic load on a spur gear transmission. The contact ratio can be affected by the tooth addendum, the pressure angle, the tooth size (diametral pitch), and the center distance. The analysis presented was performed using the NASA gear dynamics code, DANST. In the analysis, the contact ratio was varied over the range 1.20 to 2.40 by changing the length of the tooth addendum. In order to simplify the analysis, other parameters related to contact ratio were held constant. The contact ratio was found to have a significant influence on gear dynamics. Over a wide range of operating speeds, a contact ratio close to 2.0 minimized dynamic load. For low contact ratio gears (contact ratio less than 2.0), increasing the contact ratio reduced the gear dynamic load. For high contact ratio gears (contact ratio = or greater than 2.0), the selection of contact ratio should take into consideration the intended operating speeds. In general, high contact ratio gears minimized dynamic load better than low contact ratio gears.
77 FR 21142 - International Security Advisory Board (ISAB) Meeting Notice; Closed Meeting
Federal Register 2010, 2011, 2012, 2013, 2014
2012-04-09
..., international security, nuclear proliferation, and diplomacy. For more information, contact Richard W. Hartman..., DC 20520, telephone: (202) 736-4290. Dated: March 28, 2012. Richard W. Hartman II, Executive Director...
76 FR 36167 - International Security Advisory Board (ISAB) Meeting Notice; Closed Meeting
Federal Register 2010, 2011, 2012, 2013, 2014
2011-06-21
..., international security, nuclear proliferation, and diplomacy. For more information, contact Richard W. Hartman..., DC 20520, telephone: (202) 736-4290. Dated: June 13, 2011. Richard W. Hartman, II., Executive...
Code of Federal Regulations, 2011 CFR
2011-07-01
... practical matter, the State licensing agency should be contacted early in the planning or design stage of a... completion of the final space layout of the building. (ii) Advise that the State licensing agency must...
Code of Federal Regulations, 2013 CFR
2013-07-01
... practical matter, the State licensing agency should be contacted early in the planning or design stage of a... completion of the final space layout of the building. (ii) Advise that the State licensing agency must...
75 FR 54419 - Environmental Impact Statement: Queens County, NY
Federal Register 2010, 2011, 2012, 2013, 2014
2010-09-07
... published in the Federal Register on March 12, 2004. FOR FURTHER INFORMATION CONTACT: Jeffrey W. Kolb... NEPA Class II Categorical Exclusion. Issued on August 25, 2010. Jeffrey W. Kolb, Division Administrator...
76 FR 2883 - Humboldt Resource Advisory Committee (RAC)
Federal Register 2010, 2011, 2012, 2013, 2014
2011-01-18
... INFORMATION CONTACT: Adam Dellinger, Committee Coordinator, at (707) 441-3569; e-mail [email protected] review of all Title II project proposals received to date. Dated: January 10, 2011. Tyrone Kelley, Forest...
30 CFR 1227.103 - What must a State's delegation proposal contain?
Code of Federal Regulations, 2011 CFR
2011-07-01
... commerce capabilities, and data storage capabilities; (B) Accessing reference data; (C) Contacting...) Providing data to other Federal agencies; (ii) Whether you currently have the equipment you will need to...
Moshaverinia, Alireza; Roohpour, Nima; Ansari, Sahar; Moshaverinia, Maryam; Schricker, Scott; Darr, Jawwad A; Rehman, Ihtesham U
2009-10-01
It has been found that polyacids containing an N-vinylpyrrolidinone (NVP) comonomer produces a glass inomer cement with improved mechanical and handling properties. The objective of this study was to investigate the effect of NVP modified polyelectrolytes on the surface properties and shear bond strength to dentin of glass ionomer cements. Poly(acrylic acid (AA)-co-itaconic acid (IA)-co-N-vinylpyrrolidone) was synthesized by free radical polymerization. The terpolymer was characterized using (1)H NMR, FTIR spectroscopy and viscometry for solution properties. The synthesized polymers were used in glass ionomer cement formulations (Fuji II commercial GIC). Surface properties (wettability) of modified cements were studied by water contact angle measurements as a function of time. Work of adhesion values of different surfaces was also determined. The effect of NVP modified polyacid, on bond strength of glass-ionomer cement to dentin was also investigated. The mean data obtained from contact angle and bonding strength measurements were subjected to one- and two-way analysis of variance (ANOVA) at alpha=0.05. Results showed that NVP modified glass ionomer cements showed significantly lower contact angles (theta=47 degrees) and higher work of adhesion (WA=59.4 erg/cm(2)) in comparison to commercially available Fuji II GIC (theta=60 degrees and WA=50.3 erg/cm(2), respectively). The wettability of dentin surfaces conditioned with NVP containing terpolymer was higher (theta=21 degrees, WA=74.2 erg/cm(2)) than dentin conditioned with Fuji conditioner (theta=30 degrees, WA=69 erg/cm(2)). The experimental cement also showed higher but not statistically significant values for shear bond strength to dentin (7.8 MPa), when compared to control group (7.3 MPa). It was concluded that NVP containing polyelectrolytes are better dentin conditioners than the commercially available dentin conditioner (Fuji Cavity Conditioner, GC). NVP containing terpolymers can enhance the surface properties of GICs and also increase their bond strength to the dentin.
1982-05-01
semiconductor Schottky-barrier contacts are used in many semiconductor devices, including switches, rectifiers, varactors , IMPATTs, mixer and detector...ionic materials such as most of the II-VI compound semiconductors (e.g. ZnS and ZnO) and the transition-metal oxides , the barrier height is strongly...the alloying process described above is nonuniformity, due to the incomplete removal of residual surface oxides prior to the evaporation of the metal
Gelber, C; Gemmell, L; McAteer, D; Homola, M; Swain, P; Liu, A; Wilson, K J; Gefter, M
1997-03-01
Immune regulation of contact sensitivity to the poison ivy/oak catechol was studied at the level of class II MHC-restricted T cell recognition of hapten:peptide conjugates. In this study we have shown that 1) T cells from C3H/HeN (H-2k) mice, immunized with a synthetic I-Ak binding peptide coupled to 3-pentadecyl-catechol (PDC; a representative catechol in urushiol), recognized peptides derived from syngeneic cells linked to the same catechol; 2) T cells from draining lymph nodes of C3H/HeN mice skin-painted with PDC proliferated in response to a peptide carrier:PDC conjugate only when it was linked at the 7th, but not the 4th or the 10th, position on the peptide carrier; and 3) tolerization studies confirmed down-regulation of PDC-induced delayed-type hypersensitivity following treatment with a single I-Ak binding peptide carrying PDC covalently bound to a lysine residue at the middle (7th) TCR contact position. Tolerization with peptide:PDC conjugate resulted in abrogation of hapten-specific T cell proliferative responses that correlated with diminished IL-2 secretion. On the basis of these data we propose that it may be sufficient to couple the hapten at a single, well-chosen position on a carrier peptide to target a relevant population of T cells involved in contact sensitivity.
Optimizing tooth form with direct posterior composite restorations.
Raghu, Ramya; Srinivasan, Raghu
2011-10-01
Advances in material sciences and technology have provided today's clinicians the strategies to transform the mechanistic approach of operative dentistry into a biologic philosophy. In the last three decades, composite resins have gone from being just an esthetically pleasing way of restoring Class III and Class IV cavities to become the universal material for both anterior and posterior situations as they closely mimic the natural esthetics while restoring the form of the human dentition. In order to enhance their success, clinicians have to rethink their protocol instead of applying the same restorative concepts and principles practiced with metallic restorations. Paralleling the evolution of posterior composite resin materials, cavity designs, restorative techniques and armamentarium have also developed rapidly to successfully employ composite resins in Class II situations. Most of the earlier problems with posterior composites such as poor wear resistance, polymerization shrinkage, postoperative sensitivity, predictable bonding to dentin, etc., have been overcome to a major extent. However, the clinically relevant aspect of achieving tight contacts in Class II situations has challenged clinicians the most. This paper reviews the evolution of techniques and recent developments in achieving predictable contacts with posterior composites. A Medline search was performed for articles on "direct posterior composite contacts." The keywords used were "contacts and contours of posterior composites." The reference list of each article was manually checked for additional articles of relevance.
Method for introducing unidirectional nested deletions
Dunn, J.J.; Quesada, M.A.; Randesi, M.
1999-07-27
Disclosed is a method for the introduction of unidirectional deletions in a cloned DNA segment. More specifically, the method comprises providing a recombinant DNA construct comprising a DNA segment of interest inserted in a cloning vector. The cloning vector has an f1 endonuclease recognition sequence adjacent to the insertion site of the DNA segment of interest. The recombinant DNA construct is then contacted with the protein pII encoded by gene II of phage f1 thereby generating a single-stranded nick. The nicked DNA is then contacted with E. coli Exonuclease III thereby expanding the single-stranded nick into a single-stranded gap. The single-stranded gapped DNA is then contacted with a single-strand-specific endonuclease thereby producing a linearized DNA molecule containing a double-stranded deletion corresponding in size to the single-stranded gap. The DNA treated in this manner is then incubated with DNA ligase under conditions appropriate for ligation. Also disclosed is a method for producing single-stranded DNA probes. In this embodiment, single-stranded gapped DNA, produced as described above, is contacted with a DNA polymerase in the presence of labeled nucleotides to fill in the gap. This DNA is then linearized by digestion with a restriction enzyme which cuts outside the DNA segment of interest. The product of this digestion is then denatured to produce a labeled single-stranded nucleic acid probe. 1 fig.
Method for introducing unidirectional nested deletions
Dunn, John J.; Quesada, Mark A.; Randesi, Matthew
1999-07-27
Disclosed is a method for the introduction of unidirectional deletions in a cloned DNA segment. More specifically, the method comprises providing a recombinant DNA construct comprising a DNA segment of interest inserted in a cloning vector, the cloning vector having an f1 endonuclease recognition sequence adjacent to the insertion site of the DNA segment of interest. The recombinant DNA construct is then contacted with the protein pII encoded by gene II of phage f1 thereby generating a single-stranded nick. The nicked DNA is then contacted with E. coli Exonuclease III thereby expanding the single-stranded nick into a single-stranded gap. The single-stranded gapped DNA is then contacted with a single-strand-specific endonuclease thereby producing a linearized DNA molecule containing a double-stranded deletion corresponding in size to the single-stranded gap. The DNA treated in this manner is then incubated with DNA ligase under conditions appropriate for ligation. Also disclosed is a method for producing single-stranded DNA probes. In this embodiment, single-stranded gapped DNA, produced as described above, is contacted with a DNA polymerase in the presence of labeled nucleotides to fill in the gap. This DNA is then linearized by digestion with a restriction enzyme which cuts outside the DNA segment of interest. The product of this digestion is then denatured to produce a labeled single-stranded nucleic acid probe.
Method for producing labeled single-stranded nucleic acid probes
Dunn, John J.; Quesada, Mark A.; Randesi, Matthew
1999-10-19
Disclosed is a method for the introduction of unidirectional deletions in a cloned DNA segment. More specifically, the method comprises providing a recombinant DNA construct comprising a DNA segment of interest inserted in a cloning vector, the cloning vector having an f1 endonuclease recognition sequence adjacent to the insertion site of the DNA segment of interest. The recombinant DNA construct is then contacted with the protein pII encoded by gene II of phage f1 thereby generating a single-stranded nick. The nicked DNA is then contacted with E. coli Exonuclease III thereby expanding the single-stranded nick into a single-stranded gap. The single-stranded gapped DNA is then contacted with a single-strand-specific endonuclease thereby producing a linearized DNA molecule containing a double-stranded deletion corresponding in size to the single-stranded gap. The DNA treated in this manner is then incubated with DNA ligase under conditions appropriate for ligation. Also disclosed is a method for producing single-stranded DNA probes. In this embodiment, single-stranded gapped DNA, produced as described above, is contacted with a DNA polymerase in the presence of labeled nucleotides to fill in the gap. This DNA is then linearized by digestion with a restriction enzyme which cuts outside the DNA segment of interest. The product of this digestion is then denatured to produce a labeled single-stranded nucleic acid probe.
Social contact patterns can buffer costs of forgetting in the evolution of cooperation.
Stevens, Jeffrey R; Woike, Jan K; Schooler, Lael J; Lindner, Stefan; Pachur, Thorsten
2018-06-13
Analyses of the evolution of cooperation often rely on two simplifying assumptions: (i) individuals interact equally frequently with all social network members and (ii) they accurately remember each partner's past cooperation or defection. Here, we examine how more realistic, skewed patterns of contact-in which individuals interact primarily with only a subset of their network's members-influence cooperation. In addition, we test whether skewed contact patterns can counteract the decrease in cooperation caused by memory errors (i.e. forgetting). Finally, we compare two types of memory error that vary in whether forgotten interactions are replaced with random actions or with actions from previous encounters. We use evolutionary simulations of repeated prisoner's dilemma games that vary agents' contact patterns, forgetting rates and types of memory error. We find that highly skewed contact patterns foster cooperation and also buffer the detrimental effects of forgetting. The type of memory error used also influences cooperation rates. Our findings reveal previously neglected but important roles of contact pattern, type of memory error and the interaction of contact pattern and memory on cooperation. Although cognitive limitations may constrain the evolution of cooperation, social contact patterns can counteract some of these constraints. © 2018 The Author(s).
Yang, Zelong; Chen, Zhu; Liu, Kang; Bai, Yiguang; Jiang, Ting; Feng, Daxiong; Feng, Gang
2013-10-01
To explore the possibility of constructing tissue engineered cartilage complex three-dimensional nano-scaffold with collagen type II and hyaluronic acid (HA) by electrospinning. The three-dimensional porous nano-scaffolds were prepared by electrospinning techniques with collagen type II and HA (8 : 1, W : W), which was dissolved in mixed solvent of 3-trifluoroethanol and water (1 : 1, V : V). The morphology were observed by light microscope and scanning electron microscope (SEM). And the porosity, water absorption rate, contact angle, and degradation rate were detected. Chondrocytes were harvested from 1-week-old Japanese white rabbit, which was disgested by 0.25% trypsin 30 minutes and 1% collagenase overlight. The passage 2 chondrocytes were seeded on the nano-scaffold. The cell adhesion and proliferation were evaluated by cell counting kit 8 (CCK-8). The cell-scaffold composites were cultured for 2 weeks in vitro, and the biological morphology and extracelluar matrix (ECM) secretion were observed by histological analysis. The optimal electrospinning condition of nano-scaffold was 10% electrospinning solution concentration, 10 cm receiver distance, 5 mL/h spinning injection speed. The scaffold had uniform diameter and good porosity through the light microscope and SEM. The diameter was 300-600 nm, and the porosity was 89.5% +/- 25.0%. The contact angle was (35.6 +/- 3.4) degrees, and the water absorption was 1 120% +/- 34% at 24 hours, which indicated excellent hydrophilicity. The degradation rate was 42.24% +/- 1.51% at 48 days. CCK-8 results showed that the adhesive rate of cells with scaffold was 169.14% +/- 11.26% at 12 hours, and the cell survival rate was 126.03% +/- 4.54% at 7 days. The histological and immunohistochemical staining results showed that the chondrocytes could grow well on the scaffold and secreted ECM. And the similar cartilage lacuma structure could be found at 2 weeks after co-culture, which suggested that hyaline cartilage formed. The collage type II and HA complex three-dimensional nano-scaffold has good physicochemical properties and excellent biocompatibility, so it can be used as a tissue engineered cartilage
Analysis of injuries' prevalence in surfers from Paraná seacoast
de Moraes, Gabriela Chueiri; Guimarães, Ana Tereza Bittencourt; Gomes, Anna Raquel Silveira
2013-01-01
OBJECTIVE: to analyze the prevalence of musculoskeletal injuries of surfers from the Paraná's seacoast. METHODS: Sixty men (27 ± 6 years) completed a surf semi structured questionnaire (category, time of daily practice, frequency and exercises performed before and/or after surfing) and characteristics of injuries induced by this sport. A descriptive analysis of the data on distribution of the relative frequency was performed. RESULTS: It was found that 70% of the respondents practiced surfing as a relaxing activity, 28% were amateurs and 2% were professionals, who were surfing for 10 years or more. Most of them surfed between 2 to 4 times a week during 2 to 4 hours a day. The most common exercise performed before surfing was upper and lower limbs stretching and no exercises at all was done after practice. The most common injury was contusion (29%), lower limb was the most affected segment (46%) and the most common cause of injury was due to contact with the board (52%). The interruption period mostly reported was 1-3 months and the most frequent treatment was taking medicines. CONCLUSIONS: Recreational was the predominant category of surfers with lower limb's contusion as the most common musculoskeletal injury, resulting from contact with the board, being treated with medication and rest. Level of Evidence II, Retrospective Study. PMID:24453671
Swedish Acceptance and Action Questionnaire (SAAQ): a psychometric evaluation.
Lundgren, Tobias; Parling, Thomas
2017-06-01
Psychological inflexibility and experiential avoidance are equivalent (with somewhat different connotations) concepts and refer to an unwillingness to remain in contact with particular private events. This concept is most often measured by the Acceptance and Action Questionnaire (AAQ-II) and is strongly related to psychopathology and behavioral effectiveness. In this study, the preliminary psychometric properties of the Swedish version of the AAQ-II (Swedish Acceptance and Action Questionnaire-SAAQ) are presented. The study is done in two steps. In the first step, the 10-item version of the AAQ-II is investigated through principal component analysis (n = 147). Secondly, due to problems with the component structure, the instrument is reduced to a six-item version and its validity and internal consistency are investigated (n = 154). The six-item version shows good concurrent and convergent validity as well as satisfying internal consistency (α = .85). Furthermore, the Swedish six-item version of the AAQ-II showed one strong component. Test-retest reliability was satisfactory (r = .80; n = 228). In future research, predictive and external validity would be important to investigate in order to further ensure that the SAAQ is a useful measure for clinical research. In conclusion, the SAAQ has satisfactory psychometric properties, but more data need to be gathered to further explore the possibilities for the instruments in Swedish contexts.
NASA Astrophysics Data System (ADS)
Zhang, Hui; Wen, Xing; Wang, Yingxia
2007-05-01
Inorganic sulfate- and organic dodecylbenzenesulfonate (DBS)-intercalated zinc-iron layered double hydroxides (LDHs) materials were prepared by one-step coprecipitation method from a mixed salt solutions containing Zn(II), Fe(II) and Fe(III) salts. The as-prepared samples have been characterized by X-ray powder diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), low-temperature nitrogen adsorption, scanning electron microscopy (SEM), inductively coupled plasma emission spectroscopy (ICP), and Mössbauer spectroscopy (MS). The XRD analyses demonstrate the typical LDH-like layered structural characteristics of both products. The room temperature MS results reveal the characteristics of both the Fe(II) and Fe(III) species for SO 42--containing product, while only the Fe(III) characteristic for DBS-containing one. The combination characterization results and Rietveld analysis illustrate that the SO 42--containing product possesses the Green Rust two (GR2)-like crystal structure with an approximate chemical composition of [Zn 0.435·Fe II0.094·Fe III0.470·(OH) 2]·(SO 42-) 0.235·1.0H 2O, while the DBS-containing one exhibits the common LDH compound-like structure. The contact angle measurement indicates the evident hydrophobic properties of DBS-containing nanocomposite, compared with SO 42--containing product, due to the modification of the internal and external surface of LDHs by the organic hydrophobic chain of DBS.
Cumulative hip contact stress predicts osteoarthritis in DDH.
Mavcic, Blaz; Iglic, Ales; Kralj-Iglic, Veronika; Brand, Richard A; Vengust, Rok
2008-04-01
Hip stresses are generally believed to influence whether a hip develops osteoarthritis (OA); similarly, various osteotomies have been proposed to reduce contact stresses and the risk of OA. We asked whether elevated hip contact stress predicted osteoarthritis in initially asymptomatic human hips. We identified 58 nonoperatively treated nonsubluxated hips with developmental dysplasia (DDH) without symptoms at skeletal maturity; the control group included 48 adult hips without hip disease. The minimum followup was 20 years (mean, 29 years; range, 20-41 years). Peak contact stress was computed with the HIPSTRESS method using anteroposterior pelvic radiographs at skeletal maturity. The cumulative contact stress was determined by multiplying the peak contact stress by age at followup. We compared WOMAC scores and radiographic indices of OA. Dysplastic hips had higher mean peak contact and higher mean cumulative contact stress than normal hips. Mean WOMAC scores and percentage of asymptomatic hips in the study group (mean age 51 years) were similar to those in the control group (mean age 68 years). After adjusting for gender and age, the cumulative contact stress, Wiberg center-edge angle, body mass index, but not the peak contact stress, independently predicted the final WOMAC score in dysplastic hips but not in normal hips. Cumulative contact stress predicted early hip OA better than the Wiberg center-edge angle. Level II, prognostic study. See the Guidelines for Authors for a complete description of levels of evidence.
Sakai, Hiroshi; Tokuhara, Shunsuke; Murakami, Michio; Kosaka, Koji; Oguma, Kumiko; Takizawa, Satoshi
2016-01-01
Due to decreasing water demands in Japan, hydraulic retention times of water in piped supply systems has been extended, resulting in a longer contact time with disinfectants. However, the effects of extended contact time on the formation of various disinfection byproducts (DBPs), including carbonaceous DBPs such as trihalomethane (THM) and haloacetic acid (HAA), and nitrogenous DBPs such as nitrosodimethylamine (NDMA) and nitrosomorpholine (NMor), have not yet been investigated in detail. Herein, we compared the formation of these DBPs by chlorination and chloramination for five water samples collected from rivers and a dam in Japan, all of which represent municipal water supply sources. Water samples were treated by either filtration or a combination of coagulation and filtration. Treated samples were subjected to a DBP formation potential test by either chlorine or chloramine for contact times of 1 day or 4 days. Four THM species, nine HAA species, NDMA, and NMor were measured by GC-ECD or UPLC-MS/MS. Lifetime cancer risk was calculated based on the Integrated Risk Information System unit risk information. The experiment and analysis focused on (i) prolonged contact time from 1 day to 4 days, (ii) reduction efficiency by conventional treatment, (iii) correlations between DBP formation potentials and water quality parameters, and (iv) the contribution of each species to total risk. With an increased contact time from 1 day to 4 days, THM formation increased to 420% by chloramination. Coagulation-filtration treatment showed that brominated species in THMs are less likely to be reduced. With the highest unit risk among THM species, dibromochloromethane (DBCM) showed a high correlation with bromine, but not with organic matter parameters. NDMA contributed to lifetime cancer risk. The THM formation pathway should be revisited in terms of chloramination and bromine incorporation. It is also recommended to investigate nitrosamine formation potential by chloramination. Copyright © 2015 Elsevier Ltd. All rights reserved.
An experimental analysis of the real contact area between an electrical contact and a glass plane
NASA Astrophysics Data System (ADS)
Down, Michael; Jiang, Liudi; McBride, John W.
2013-06-01
The exact contact between two rough surfaces is usually estimated using statistical mathematics and surface analysis before and after contact has occurred. To date the majority of real contact and loaded surfaces has been theoretical or by numerical analyses. A method of analysing real contact area under various loads, by utilizing a con-contact laser surface profiler, allows direct measurement of contact area and deformation in terms of contact force and plane displacement between two surfaces. A laser performs a scan through a transparent flat side supported in a fixed position above the base. A test contact, mounted atop a spring and force sensor, and a screw support which moves into contact with the transparent surface. This paper presents the analysis of real contact area of various surfaces under various loads. The surfaces analysed are a pair of Au coated hemispherical contacts, one is a used Au to Au coated multi-walled carbon nanotubes surface, from a MEMS relay application, the other a new contact surface of the same configuration.
Arantes de Carvalho, Gabriel G; Kondaveeti, Stalin; Petri, Denise F S; Fioroto, Alexandre M; Albuquerque, Luiza G R; Oliveira, Pedro V
2016-12-01
Analytical methods for the determination of rare earth elements (REE) in natural waters by plasma spectrochemical techniques often require sample preparation procedures for analytes preconcentration as well as for removing matrix constituents, that may interfere on the analytical measurements. In the present work, calcium alginate (CA) beads were used for the first time aiming at Ce, La and Nd preconcentration from groundwater samples for further determination by inductively coupled plasma optical emission spectrometry (ICP OES). Test samples were analyzed in batch mode by transferring a 40mL test portion (pH=5±0.2) into a 50mL polyethylene flask containing 125mg CA beads. After 15min contact, the analytes were quantitatively extracted from the loaded CA beads with 2.0mL of 1.0molL -1 HCl solution for further determination by ICP OES, using Ce (II) 456.236, La (II) 379.478 and Nd (II) 430.358nm emission lines. The proposed approach is a reliable alternative for REE single-stage preconcentration from aqueous samples, as it provided accurate results based on the addition and recovery analysis of groundwater. The results obtained by the proposed method were also compared with those from reference method based on inductively coupled plasma mass spectrometry (ICP-MS) and no significant differences were observed after applying the Student's t-test at 95% confidence level. Copyright © 2016 Elsevier B.V. All rights reserved.
Campbell, Darren; Carnell, Sarah Maria; Eden, Russell John
2013-05-01
Contact angle, as a representative measure of surface wettability, is often employed to interpret contact lens surface properties. The literature is often contradictory and can lead to confusion. This literature review is part of a series regarding the analysis of hydrogel contact lenses using contact angle techniques. Here we present an overview of contact angle terminology, methodology, and analysis. Having discussed this background material, subsequent parts of the series will discuss the analysis of contact lens contact angles and evaluate differences in published laboratory results. The concepts of contact angle, wettability and wetting are presented as an introduction. Contact angle hysteresis is outlined and highlights the advantages in using dynamic analytical techniques over static methods. The surface free energy of a material illustrates how contact angle analysis is capable of providing supplementary surface characterization. Although single values are able to distinguish individual material differences, surface free energy and dynamic methods provide an improved understanding of material behavior. The frequently used sessile drop, captive bubble, and Wilhelmy plate techniques are discussed. Their use as both dynamic and static methods, along with the advantages and disadvantages of each technique, is explained. No single contact angle technique fully characterizes the wettability of a material surface, and the application of complimenting methods allows increased characterization. At present, there is not an ISO standard method designed for soft materials. It is important that each contact angle technique has a standard protocol, as small protocol differences between laboratories often contribute to a variety of published data that are not easily comparable.
Gutha, Yuvaraja; Zhang, Yaping; Zhang, Weijiang; Jiao, Xu
2017-04-01
Metal ions cause a serious public health problem. It is a great challenge to find an effective and efficient adsorbent to remove heavy metals from wastewater. Chitosan-based adsorbents are potential and effective for heavy metal ion removal. Hence a novel m-ECCSB was synthesized, characterized and utilized as an adsorbent for the removal of Cu(II) ions from aqueous solution. Various factors affecting the uptake behavior such as pH, adsorbent dosage, contact time, initial concentration of Cu(II) and temperature effect were investigated. Maximum adsorption capability (123.10mg/g) was obtained at pH=6, adsorbent dose of=250mg, rotational speed=200rpm, contact time=60min, and temperature of 323K. The result of the kinetic study shows that the adsorption of Cu(II) could be described by the pseudo-second-order equation. Equilibrium data were analysed with the Langmuir, Freundlich and Dubinin-Radushkevich isotherms and Langmuir model was found to provide the best fit of the experimental data. The thermodynamic parameters showed that the adsorption of Cu(II) onto m-ECCSB was spontaneous (ΔG°=-8.990, -10.00 and -10.593kJ/mol), endothermic (ΔH°=15.674, 15.478 and 15.699kJ/mol) and ΔS° (0.0814J/molK) suggests an increased randomness at the solid/solution interface under the studied conditions. Copyright © 2017 Elsevier B.V. All rights reserved.
1997-06-09
A 40 K Fastrac II duration test performed at Marshall Test Stand 116. The purpose of this test was to gauge the length of time between contact of TEA (Triethylenealuminum) and LOX (liquid oxygen) as an ignitor for the Fastrac engine.
76 FR 12356 - Farm Credit Administration Board; Sunshine Act; Regular Meeting
Federal Register 2010, 2011, 2012, 2013, 2014
2011-03-07
... concludes its business. FOR FURTHER INFORMATION CONTACT: Dale L. Aultman, Secretary to the Farm Credit... on Borrowers Rights--Part II. Update on Dodd-Frank Rulemaking Projects. Dated: March 2, 2011. Dale L...
Porous silicon powder as an adsorbent of heavy metal (nickel)
NASA Astrophysics Data System (ADS)
Nabil, Marwa; Motaweh, Hussien A.
2018-04-01
New and inexpensive nanoporous silicon (NPS) powder was prepared by alkali chemical etching using sonication technique and was subsequently investigated as an adsorbent in batch systems for the adsorption Ni(II) ions in an aqueous solution. The optimum conditions for the Ni(II) ion adsorption capacity of the NPS powder were studied in detail by varying parameters such as the initial Ni(II) concentration, the solution pH value, the adsorption temperature and contact time. The results indicated that the maximum adsorption capacity and the maximum removal percent of Ni(II) reached 2665.33 mg/g and 82.6%, respectively, at an initial Ni(II) concentration of 100 mg/L, adsorption time of 30 min and no effect of the solution pH and adsorption temperature.
A theoretical and experimental investigation of impact control for manipulators
NASA Technical Reports Server (NTRS)
Volpe, Richard; Khosla, Pradeep
1993-01-01
This article describes a simple control strategy for stable hardon-hard contact of a manipulator with the environment. The strategy is motivated by recognition of the equivalence of proportional gain explicit force control and impedance control. It is shown that negative proportional force gains, or impedance mass ratios less than unity, can equivalently provide excellent impact response without bouncing. This result is indicated by an analysis performed with an experimentally determined arm/sensor/environment model. The results are corroborated by experimental data from implementation of the control algorithms on the CMU DD Arm II system. The results confirm that manipulator impact against a stiff environment without bouncing can be readily handled by this novel control strategy.
Bílek, František; Sulovská, Kateřina; Lehocký, Marián; Sáha, Petr; Humpolíček, Petr; Mozetič, Miran; Junkar, Ita
2013-02-01
Three monomers (allylamine, N-allylmethylamine and N,N-dimethylallylamine) were used for grafting onto air plasma activated LDPE surface. Antibacterial agent triclosan was anchored on such substrates. Influence of graft type on the antibacterial properties was determined. Increase of antibacterial activity and amount of deposited antibacterial agent for N-allylmethylamine and N,N-dimethylallylamine monomers were examined. Surface characteristics were measured by means of static contact angle measurement with surface energy evaluation, ATR-FTIR spectroscopy, XPS and SEM characterization analysis. Antibacterial properties were tested in vitro by inhibition zone method on agar plates for Staphylococcus aureus and Escherichia coli strains. Copyright © 2012 Elsevier B.V. All rights reserved.
Palladium (Ii) Catalyzed Polymerization Of Norbornene And Acrylates
Sen, Ayusman; Kacker, Smita; Hennis, April; Polley, Jennifer D.
2001-10-09
Homopolymers or copolymers of acrylates, homopolymers or copolymers of norbornenes, and copolymers of acrylates with norbornenes, may be prepared by contacting acrylate and/or norbornene monomer reactant under polymerization conditions and in the presence of a solvent with a catalyst system consisting essentially of a Pd(II) dimer component having the formula: where L is a monodentate phosphorus or nitrogen ligand, X is an anionic group, and R is an alkyl or aryl group.
Moisture Absorption in Certain Tropical American Woods
1949-08-01
surface area was in unobstructed contact with the salt water. Similar wire mesh racks were weighted and placed on top of the specimens to keep them...Oak (Quercus alba)" Br. Guiana Honduras United States (control) II II Total absorption by 2 x 2 x 6-inch uncoated specimens. Probably sapwood ...only. /2 ~~ Probably sapwood Table 3 (Continued) Species Source Increase over 40 percent Fiddlewood (Vit ex Gaumeri) Roble Blanco (Tabebuia
DOE Office of Scientific and Technical Information (OSTI.GOV)
Panaccione, Charles; Staab, Greg; Meuleman, Erik
ION has developed a mathematically driven model for a contacting device incorporating mass transfer, heat transfer, and computational fluid dynamics. This model is based upon a parametric structure for purposes of future commercialization. The most promising design from modeling was 3D printed and tested in a bench scale CO 2 capture unit and compared to commercially available structured packing tested in the same unit.
Karl Otto Himmler, manufacturer of the first contact lens.
Pearson, Richard M
2007-03-01
In 1889 August Müller (1864-1949) reported the correction of his own high myopia with a ground scleral contact lens that had been manufactured in Berlin two years earlier. This paper provides the first conclusive identification, based upon primary sources, of the manufacturer of these lenses. They were made by an optical engineer, Karl Otto Himmler (1841-1903), whose firm enjoyed, until the outbreak of World War II, an international reputation for the manufacture of microscopes and their accessories.
HTS thin films: Passive microwave components and systems integration issues
DOE Office of Scientific and Technical Information (OSTI.GOV)
Miranda, F.A.; Chorey, C.M.; Bhasin, K.B.
1994-12-31
The excellent microwave properties of the High-Temperature-Superconductors (HTS) have been amply demonstrated in the laboratory by techniques such as resonant cavity, power transmission and microstrip resonator measurements. The low loss and high Q passive structures made possible with HTS, present attractive options for applications in commercial, military and space-based systems. However, to readily insert HTS into these systems improvement is needed in such areas as repeatability in the deposition and processing of the HTS films, metal-contact formation, wire bonding, and overall film endurance to fabrication and assembly procedures. In this paper we present data compiled in our lab which illustratemore » many of the problems associated with these issues. Much of this data were obtained in the production of a space qualified hybrid receiver-downconverter module for the Naval Research Laboratory`s High Temperature Superconductivity Space Experiment II (HTSSE-II). Examples of variations observed in starting films and finished circuits will be presented. It is shown that under identical processing the properties of the HTS films can degrade to varying extents. Finally, we present data on ohmic contacts and factors affecting their adhesion to HTS films, strength of wire bonds made to such contacts, and aging effects.« less
Molecular docking of superantigens with class II major histocompatibility complex proteins.
Olson, M A; Cuff, L
1997-01-01
The molecular recognition of two superantigens with class II major histocompatibility complex molecules was simulated by using protein-protein docking. Superantigens studied were staphylococcal enterotoxin B (SEB) and toxic shock syndrome toxin-1 (TSST-1) in their crystallographic assemblies with HLA-DR1. Rigid-body docking was performed sampling configurational space of the interfacial surfaces by employing a strategy of partitioning the contact regions on HLA-DR1 into separate molecular recognition units. Scoring of docked conformations was based on an electrostatic continuum model evaluated with the finite-difference Poisson-Boltzmann method. Estimates of nonpolar contributions were derived from the buried molecular surface areas. We found for both superantigens that docking the HLA-DR1 surface complementary with the SEB and TSST-1 contact regions containing a homologous hydrophobic surface loop provided sufficient recognition for the reconstitution of native-like conformers exhibiting the highest-scoring free energies. For the SEB complex, the calculations were successful in reproducing the total association free energy. A comparison of the free-energy determinants of the conserved hydrophobic contact residue indicates functional similarity between the two proteins for this interface. Though both superantigens share a common global association mode, differences in binding topology distinguish the conformational specificities underlying recognition.
Group B streptococci in the female genital tract and nosocomial colonization of newborns.
Duben, J; Jelínková, J; Neubauer, M
1978-11-01
In a long-term study, rates for group B streptococcus prevalence in the vagina and/or anus of nonpregnant women and pregnant women in the first trimester and in the second trimester were found as follows: 7.1%, 7.3% and 5.4% respectively. At delivery, positivity rates of 4.8% and 3.8% were found for mothers and newborns, respectively. Each pair of strains isolated from mother and newborn was of the same serotype. In 13.6% of newborns nosocomial colonization of the upper respiratory tract occurred during their stay in the maternity home. The sources were other positive newborns sharing the same boxes, the nosocomial spread proceeded in clusters. Detailed type-antigen analysis of isolates allowed identification of index cases and their direct contacts. Types Ib, Ic, II/R, III + Ic predominated. Sexual transmission was demonstrated by findings of identical serotypes in both partners: 23% of male partners of nonpregnant positive women and 9.1% of partners of pregnant positive women had positive urine samples. A control male group consisting of psychiatric sanatorium patients without sexual contact repeatedly exhibited a positivity rate of 2%.
Cell migration, intercalation and growth regulate mammalian cochlear extension.
Driver, Elizabeth Carroll; Northrop, Amy; Kelley, Matthew W
2017-10-15
Developmental remodeling of the sensory epithelium of the cochlea is required for the formation of an elongated, tonotopically organized auditory organ, but the cellular processes that mediate these events are largely unknown. We used both morphological assessments of cellular rearrangements and time-lapse imaging to visualize cochlear remodeling in mouse. Analysis of cell redistribution showed that the cochlea extends through a combination of radial intercalation and cell growth. Live imaging demonstrated that concomitant cellular intercalation results in a brief period of epithelial convergence, although subsequent changes in cell size lead to medial-lateral spreading. Supporting cells, which retain contact with the basement membrane, exhibit biased protrusive activity and directed movement along the axis of extension. By contrast, hair cells lose contact with the basement membrane, but contribute to continued outgrowth through increased cell size. Regulation of cellular protrusions, movement and intercalation within the cochlea all require myosin II. These results establish, for the first time, many of the cellular processes that drive the distribution of sensory cells along the tonotopic axis of the cochlea. © 2017. Published by The Company of Biologists Ltd.
Nivaskumar, Mangayarkarasi; Bouvier, Guillaume; Campos, Manuel; Nadeau, Nathalie; Yu, Xiong; Egelman, Edward H; Nilges, Michael; Francetic, Olivera
2014-05-06
The closely related bacterial type II secretion (T2S) and type IV pilus (T4P) systems are sophisticated machines that assemble dynamic fibers promoting protein transport, motility, or adhesion. Despite their essential role in virulence, the molecular mechanisms underlying helical fiber assembly remain unknown. Here, we use electron microscopy and flexible modeling to study conformational changes of PulG pili assembled by the Klebsiella oxytoca T2SS. Neural network analysis of 3,900 pilus models suggested a transition path toward low-energy conformations driven by progressive increase in fiber helical twist. Detailed predictions of interprotomer contacts along this path were tested by site-directed mutagenesis, pilus assembly, and protein secretion analyses. We demonstrate that electrostatic interactions between adjacent protomers (P-P+1) in the membrane drive pseudopilin docking, while P-P+3 and P-P+4 contacts determine downstream fiber stabilization steps. These results support a model of a spool-like assembly mechanism for fibers of the T2SS-T4P superfamily. Copyright © 2014 Elsevier Ltd. All rights reserved.
Nivaskumar, Mangayarkarasi; Bouvier, Guillaume; Campos, Manuel; Nadeau, Nathalie; Yu, Xiong; Egelman, Edward H.; Nilges, Michael; Francetic, Olivera
2014-01-01
SUMMARY The closely related bacterial type II secretion (T2S) and type IV pilus (T4P) systems are sophisticated machines that assemble dynamic fibers promoting protein transport, motility or adhesion. Despite their essential role in virulence, the molecular mechanisms underlying helical fiber assembly remain unknown. Here we use electron microscopy and flexible modeling to study conformational changes of PulG pili assembled by the Klebsiella oxytoca T2SS. Neural network analysis of 3900 pilus models suggested a transition path towards low-energy conformations driven by progressive increase in fiber helical twist. Detailed predictions of inter-protomer contacts along this path were tested by site-directed mutagenesis, pilus assembly and protein secretion analyses. We demonstrate that electrostatic interactions between adjacent protomers (P-P+1) in the membrane drive pseudopilin docking, while P-P+3 and P-P+4 contacts determine downstream fiber stabilization steps. These results support a new model of a spool-like assembly mechanism for fibers of the T2SS-T4P superfamily. PMID:24685147
Comparison of Gap Elements and Contact Algorithm for 3D Contact Analysis of Spiral Bevel Gears
NASA Technical Reports Server (NTRS)
Bibel, G. D.; Tiku, K.; Kumar, A.; Handschuh, R.
1994-01-01
Three dimensional stress analysis of spiral bevel gears in mesh using the finite element method is presented. A finite element model is generated by solving equations that identify tooth surface coordinates. Contact is simulated by the automatic generation of nonpenetration constraints. This method is compared to a finite element contact analysis conducted with gap elements.
Catalase-like activity studies of the manganese(II) adsorbed zeolites
NASA Astrophysics Data System (ADS)
ćiçek, Ekrem; Dede, Bülent
2013-12-01
Preparation of manganese(II) adsorbed on zeolite 3A, 4A, 5A. AW-300, ammonium Y zeolite, organophilic, molecular sieve and catalase-like enzyme activity of manganese(II) adsorbed zeolites are reported herein. Firstly zeolites are activated at 873 K for two hours before contact manganese(II) ions. In order to observe amount of adsorption, filtration process applied for the solution. The pure zeolites and manganese(II) adsorbed zeolites were analysed by FT-IR. As a result according to the FT-IR spectra, the incorporation of manganese(II) cation into the zeolite structure causes changes in the spectra. These changes are expected particularly in the pseudolattice bands connected with the presence of alumino and silicooxygen tetrahedral rings in the zeolite structure. Furthermore, the catalytic activities of the Mn(II) adsorbed zeolites for the disproportionation of hydrogen peroxide were investigated in the presence of imidazole. The Mn(II) adsorbed zeolites display efficiency in the disproportion reactions of hydrogen peroxide, producing water and dioxygen in catalase-like activity.
Design and Stress Analysis of Low-Noise Adjusted Bearing Contact Spiral Bevel Gears
NASA Technical Reports Server (NTRS)
Litvin, Faydor L.; Fuentes, Alfonso; Mullins, Baxter R.; Woods, Ron
2002-01-01
An integrated computerized approach for design and stress analysis of low-noise spiral bevel gear drives with adjusted bearing contact has been developed. The computation procedure is an iterative process, requiring four separate steps that provide: (a) a parabolic function of transmission errors that is able to reduce the effect of errors of alignment, and (b) reduction of the shift of bearing contact caused by misalignment. Application of finite element analysis permits the contact and bending stresses to be determined and investigate the formation of the bearing contact. The design of finite element models and boundary conditions is automated and does not require an intermediate CAD computer program. A commercially available finite element analysis computer program with contact capability was used to conduct the stress analysis. The theory developed is illustrated with numerical examples.
Freyschmidt-Paul, P; Sundberg, J P; Happle, R; McElwee, K J; Metz, S; Boggess, D; Hoffmann, R
1999-07-01
A type of hair loss closely resembling human alopecia areata has been described in C3H/HeJ mice. In order to test the assumed analogy with human alopecia areata, we investigated the efficacy of treatment with the contact allergen squaric acid dibutylester. In 12 C3H/HeJ mice with alopecia areata an allergic contact dermatitis was induced and elicited weekly on one side of the back by topical applications of squaric acid dibutylester. Overt hair regrowth was observed only on the treated side of the back in nine of 12 mice. Histopathologic examination revealed a change in the distribution of the inflammatory infiltrate from a dense perifollicular lymphocytic infiltrate around the mid and lower regions of hair follicles in untreated skin to a uniform presence in the upper dermis in treated skin. Immunohistomorphometric studies revealed that treatment with squaric acid dibutylester increased the CD4+/CD8+ ratio from approximately 1:2 in untreated alopecia areata to 1:1 in treated alopecia areata. Additional immunohistochemical investigations showed an aberrant expression of major histocompatibility complex class I, major histocompatibility complex class II and intercellular adhesion molecule 1 on keratinocytes of the mid and lower parts of hair follicles in untreated alopecia areata. In successfully treated skin ectopic major histocompatibility complex class I and II expression was clearly reduced, whereas intercellular adhesion molecule 1 expression showed only minor changes. In conclusion, alopecia areata-like hair loss in C3H/HeJ mice responded to treatment with the contact sensitizer squaric acid dibutylester analogous to human alopecia areata. Moreover, successful treatment changes the aberrant expression of major histocompatibility complex class I and II in a way similar to that observed in human alopecia areata. These observations support the concept that alopecia areata-like hair loss in C3H/HeJ mice can be utilized as an appropriate model for the study of human alopecia areata.
The role of RNA structure in the interaction of U1A protein with U1 hairpin II RNA
Law, Michael J.; Rice, Andrew J.; Lin, Patti; Laird-Offringa, Ite A.
2006-01-01
The N-terminal RNA Recognition Motif (RRM1) of the spliceosomal protein U1A interacting with its target U1 hairpin II (U1hpII) has been used as a paradigm for RRM-containing proteins interacting with their RNA targets. U1A binds to U1hpII via direct interactions with a 7-nucleotide (nt) consensus binding sequence at the 5′ end of a 10-nt loop, and via hydrogen bonds with the closing C–G base pair at the top of the RNA stem. Using surface plasmon resonance (Biacore), we have examined the role of structural features of U1hpII in binding to U1A RRM1. Mutational analysis of the closing base pair suggests it plays a minor role in binding and mainly prevents “breathing” of the loop. Lengthening the stem and nontarget part of the loop suggests that the increased negative charge of the RNA might slightly aid association. However, this is offset by an increase in dissociation, which may be caused by attraction of the RRM to nontarget parts of the RNA. Studies of a single stranded target and RNAs with untethered loops indicate that structure is not very relevant for association but is important for complex stability. In particular, breaking the link between the stem and the 5′ side of the loop greatly increases complex dissociation, presumably by hindering simultaneous contacts between the RRM and stem and loop nucleotides. While binding of U1A to a single stranded target is much weaker than to U1hpII, it occurs with nanomolar affinity, supporting recent evidence that binding of unstructured RNA by U1A has physiological significance. PMID:16738410
The role of RNA structure in the interaction of U1A protein with U1 hairpin II RNA.
Law, Michael J; Rice, Andrew J; Lin, Patti; Laird-Offringa, Ite A
2006-07-01
The N-terminal RNA Recognition Motif (RRM1) of the spliceosomal protein U1A interacting with its target U1 hairpin II (U1hpII) has been used as a paradigm for RRM-containing proteins interacting with their RNA targets. U1A binds to U1hpII via direct interactions with a 7-nucleotide (nt) consensus binding sequence at the 5' end of a 10-nt loop, and via hydrogen bonds with the closing C-G base pair at the top of the RNA stem. Using surface plasmon resonance (Biacore), we have examined the role of structural features of U1hpII in binding to U1A RRM1. Mutational analysis of the closing base pair suggests it plays a minor role in binding and mainly prevents "breathing" of the loop. Lengthening the stem and nontarget part of the loop suggests that the increased negative charge of the RNA might slightly aid association. However, this is offset by an increase in dissociation, which may be caused by attraction of the RRM to nontarget parts of the RNA. Studies of a single stranded target and RNAs with untethered loops indicate that structure is not very relevant for association but is important for complex stability. In particular, breaking the link between the stem and the 5' side of the loop greatly increases complex dissociation, presumably by hindering simultaneous contacts between the RRM and stem and loop nucleotides. While binding of U1A to a single stranded target is much weaker than to U1hpII, it occurs with nanomolar affinity, supporting recent evidence that binding of unstructured RNA by U1A has physiological significance.
Srinivasan, Bhadrinath; Kailasam, Vignesh; Chitharanjan, Arun; Ramalingam, Arthi
2013-01-01
The present study aimed to measure the magnitude of the collum angle (crown-root angulation) of maxillary central incisors present in Class II, division 2 malocclusion and to relate the changes in its magnitude with variations in the lower lip line. A set of 120 conventional lateral cephalograms were selected and divided into three groups of 40 each based on the type of malocclusion presented: Class II, division 2 (group 1); Class II, division 1 (group 2); and Class I (group 3). The collum angle of the maxillary central incisor was measured, and the lower lip line was recorded. Analysis of variance (ANOVA) revealed that the mean collum angle was statistically significantly different in the three groups. The mean collum angle was greatest in Class II, division 2 malocclusion (group 1). The mean collum angles were 3.24 ± 4.69 degrees, 0.95 ± 1.06 degrees, and 1.05 ± 1.50 degrees in groups 1, 2, and 3 respectively. In χ ² test comparison of the location of the lower lip line (incisal, middle, or apical third of the central incisor) among the three groups, the lower lip line was found to contact the middle third of the central incisor most frequently in Class II, division 2 malocclusion. ANOVA followed by Tukey honestly significant difference (HSD) test showed that the mean collum angle is significantly increased when the lower lip is in the middle third (P < .05) of the central incisor. Variations in magnitude of the collum angle with the change in the lower lip line suggest a probable etiologic role of the lower lip line in the development of the collum angle.
Catalytic conversion of alcohols to hydrocarbons with low benzene content
Narula, Chaitanya K.; Davison, Brian H.; Keller, Martin
2016-09-06
A method for converting an alcohol to a hydrocarbon fraction having a lowered benzene content, the method comprising: converting said alcohol to a hydrocarbon fraction by contacting said alcohol, under conditions suitable for converting said alcohol to said hydrocarbon fraction, with a metal-loaded zeolite catalyst catalytically active for converting said alcohol to said hydrocarbon fraction, and contacting said hydrocarbon fraction with a benzene alkylation catalyst, under conditions suitable for alkylating benzene, to form alkylated benzene product in said hydrocarbon fraction. Also described is a catalyst composition useful in the method, comprising a mixture of (i) a metal-loaded zeolite catalyst catalytically active for converting said alcohol to said hydrocarbon, and (ii) a benzene alkylation catalyst, in which (i) and (ii) may be in a mixed or separated state. A reactor for housing the catalyst and conducting the reaction is also described.
Catalytic conversion of alcohols to hydrocarbons with low benzene content
Narula, Chaitanya K.; Davison, Brian H.; Keller, Martin
2016-03-08
A method for converting an alcohol to a hydrocarbon fraction having a lowered benzene content, the method comprising: converting said alcohol to a hydrocarbon fraction by contacting said alcohol, under conditions suitable for converting said alcohol to said hydrocarbon fraction, with a metal-loaded zeolite catalyst catalytically active for converting said alcohol to said hydrocarbon fraction, and contacting said hydrocarbon fraction with a benzene alkylation catalyst, under conditions suitable for alkylating benzene, to form alkylated benzene product in said hydrocarbon fraction. Also described is a catalyst composition useful in the method, comprising a mixture of (i) a metal-loaded zeolite catalyst catalytically active for converting said alcohol to said hydrocarbon, and (ii) a benzene alkylation catalyst, in which (i) and (ii) may be in a mixed or separated state. A reactor for housing the catalyst and conducting the reaction is also described.
Arshadi, M; Abdolmaleki, M K; Mousavinia, F; Foroughifard, S; Karimzadeh, A
2017-01-15
This paper reports the preparation and stabilization of nano zero valent iron (NZVI) on a modified aquatic plant, Azolla filiculoides, and investigates its potential for the adsorption/reduction of Pb(II) and Hg(II) ions from aqueous media even after six months of storage in the lab condition. XRD, TEM and zeta potential results demonstrated that the Azolla-NaOH could be a good stabilizer of aged NZVI (six months) and the green support suppressed the oxidation and aggregation of immobilized NZVI. Kinetic and equilibrium models for lead and mercury ions uptake were developed by considering the effect of the initial Pb(II) and Hg(II) concentrations, contact time, adsorbent dosage, initial pH and effect of temperature. The contact time to obtain equilibrium for maximum uptake by Azolla-OH-NZVI was 20min. The removal of toxic metal ions has been monitored in terms of pseudo-first- and -second-order kinetics, and the Freundlich and Langmuir isotherms models have also been utilized to the equilibrium uptake results. The uptake kinetics followed the mechanism of the pseudo-second-order equation for all systems studied, confirming chemical sorption as the rate-limiting step of adsorption mechanisms and not involving a mass transfer in solution. The thermodynamic results confirmed that the uptake of Pb(II) and Hg(II) ions were feasible, spontaneous and endothermic at 25-80°C. XRD and zeta potential data displayed the existence of Pb(0) and Hg(0) on the Azolla-OH-NZVI surface. The nanobioadsorbent revealed high recyclability due to its reasonable uptake efficiency after 7th adsorption-desorption cycles. The proposed nano biocomposite could also be utilized to uptake Pb(II) and Hg(II) ions from the real water (Anzali lagoon water). However, coated NZVI with Azolla filiculoides as a green and environmentally friendly support suppressed rapid oxidation and aggregation of the immobilized NZVI, therefore vastly enhancing the probability of environmental transport and reducing the sedimentation and potential for toxicity. Copyright © 2016 Elsevier Inc. All rights reserved.
Contact Analysis of Nominally Flat Surfaces
2008-06-01
to analyze the simple case of Hertz-contact (a spherical body in contact with a rigid flat plane) and determine the change in contact area with...next major area was in the Hertz Contact Theory. This area allowed the authors to develop an analytical solution. The third major area was in the... bodies came into contact with one another. This research concluded with the development and testing of the Finite Element Analysis Program (FEAP) using
Tear analysis in contact lens wearers.
Farris, R L
1985-01-01
Tear analysis in contact lens wearers was compared with tear analysis in aphakics without contact lens wear and normal phakic patients. Subjects were divided into five groups: group 1, aphakic without contact lens; group 2, phakic with daily-wear hard contact lens; group 3, phakic with daily-wear soft contact lens; group 4, phakic with extended-wear soft contact lens; and group 5, aphakic with extended-wear soft contact lens. The experimental groups were compared with age- and sex-matched control groups for statistical analysis of tear variables by means of the Student's t-test. The variables measured were tear osmolarity, tear albumin, and lysozyme and lactoferrin concentrations in basal and reflex tears. Highly significant elevations of tear osmolarity were found in aphakic subjects without contact lenses. Less significant differences in tear osmolarity were found in phakic subjects with hard daily-wear lenses or with extended-wear soft lenses. Tear albumin, lysozyme, and lactoferrin in basal and reflex tears were not significantly different in the different groups of contact lens wearers or in the group of aphakic subjects without contact lenses compared with their control groups. Individual variations in tear albumin, lysozyme, and lactoferrin appeared to be responsible for the inability to demonstrate significant differences in tear composition in association with the wearing of different types of contact lenses. Older and aphakic patients demonstrated a tendency to have increased concentrations of proteins in the tears compared with younger, phakic contact lens wearers and normal controls without contact lenses. PMID:3914131
Analysis of Non-contact Acousto Thermal Signature Data (Postprint)
2016-02-01
AFRL-RX-WP-JA-2016-0321 ANALYSIS OF NON- CONTACT ACOUSTO-THERMAL SIGNATURE DATA (POSTPRINT) Amanda K. Criner AFRL/RX...October 2014 – 16 September 2015 4. TITLE AND SUBTITLE ANALYSIS OF NON- CONTACT ACOUSTO-THERMAL SIGNATURE DATA (POSTPRINT) 5a. CONTRACT NUMBER...words) The non- contact acousto-thermal signature (NCATS) is a nondestructive evaluation technique with potential to detect fatigue in materials such as
Ahmad, Ashfaq; Bhat, A H; Buang, Azizul
2018-02-01
In this study freely suspended and Ca-alginate immobilized C. vulgaris cells were used for the biosorption of Fe(II), Mn(II), and Zn(II) ions, from the aqueous solution. Experimental data showed that biosorption capacity of algal cells was strongly dependent on the operational condition such as pH, initial metal ions concentration, dosages, contact time and temperature. The maximum biosorption of Fe(II) 43.43, Mn(II) 40.98 and Zn(II) 37.43 mg/g was achieved with Ca-alginate immobilized algal cells at optimum pH of 6.0, algal cells dosage 0.6 g/L, and contact time of 450 min at room temperature. The biosorption efficiency of freely suspended and immobilized C. vulgaris cells for heavy metals removal from the industrial wastewater was validated. Modeling of biosorption kinetics showed good agreements with pseudo-second-order. Langmuir and D-R isotherm models exhibited the best fit of experimental data. The thermodynamic parameters (ΔG°, ΔH°, and ΔS°) revealed that the biosorption of considered metal ions was feasible, spontaneous and exothermic at 25-45°C. The SEM showed porous morphology which greatly helps in the biosorption of heavy metals. The Fourier transform infrared spectrophotometer (FTIR) and X-rays Photon Spectroscopy (XPS) data spectra indicated that the functional groups predominately involved in the biosorption were C-N, -OH, COO-, -CH, C=C, C=S and -C-. These results shows that immobilized algal cells in alginate beads could potentially enhance the biosorption of considered metal ions than freely suspended cells. Furthermore, the biosorbent has significantly removed heavy metals from industrial wastewater at the optimized condition.
NASA Astrophysics Data System (ADS)
Chubar, Natalia; Visser, Tom; Avramut, Cristina; de Waard, Helen
2013-01-01
The sorption of Mn(II) by viable and inactivated cells of Shewanella putrefaciens, a non-pathogenic, facultative anaerobic, gram-negative bacterium characterised as a Mn(IV) and Fe(III) reducer, was studied under aerobic conditions, as a function of pH, bacterial density and metal loading. During a short contact time (3-24 h), the adsorptive behaviour of live and dead bacteria toward Mn(II) was sufficiently similar, an observation that was reflected in the studies on adsorption kinetics at various metal loadings, effects of pH, bacteria density, isotherms and drifting of pH during adsorption. Continuing the experiment for an additional 2-30 days demonstrated that the Mn(II) sorption by suspensions of viable and autoclaved cells differed significantly from one another. The sorption to dead cells was characterised by a rapid equilibration and was described by an isotherm. In contrast, the sorption (uptake) to live bacteria exhibited a complex time-dependent uptake. This uptake began as adsorption and ion exchange processes followed by bioprecipitation, and it was accompanied by the formation of polymeric sugars (EPS) and the release of dissolved organic substances. FTIR, EXAFS/XANES and XPS demonstrated that manganese(II) phosphate was the main precipitate formed in 125 ml batches, which is the first evidence of the ability of microbes to synthesise manganese phosphates. XPS and XANES spectra did not detect Mn(II) oxidation. Although the release of protein-like compounds by the viable bacteria increased in the presence of Mn2+ (and, by contrast, the release of carbohydrates did not change), electrochemical analyses did not indicate any aqueous complexation of Mn(II) by the organic ligands.
Grigoletti, Laura; Amaddeo, Francesco; Grassi, Aldrigo; Boldrini, Massimo; Chiappelli, Marco; Percudani, Mauro; Catapano, Francesco; Fiorillo, Andrea; Bartoli, Luca; Bacigalupi, Maurizio; Albanese, Paolo; Simonetti, Simona; Perali, Federico; De Agostini, Paola; Tansella, Michele
2006-01-01
To obtain a new, well-balanced mental health funding system, through the creation of (i) a list of psychiatric interventions provided by Italian Community-based Psychiatric Services (CPS), and associated costs; (ii) a new prospective funding system for patients with a high use of resources, based on packages of care. Five Italian Community-based Psychiatric Services collected data from 1250 patients during October 2002. Socio-demographical and clinical characteristics and GAF scores were collected at baseline. All psychiatric contacts during the following six months were registered and categorised into 24 service contact types. Using elasticity equation and contact characteristics, we estimate the costs of care. Cluster analysis techniques identified packages of care. Logistic regression defined predictive variables of high use patients. Multinomial Logistic Model assigned each patient to a package of care. The sample's socio-demographic characteristics are similar, but variations exist between the different CPS. Patients were then divided into two groups, and the group with the highest use of resources was divided into three smaller groups, based on number and type of services provided. Our findings show how is possible to develop a cost predictive model to assign patients with a high use of resources to a group that can provide the right level of care. For these patients it might be possible to apply a prospective per-capita funding system based on packages of care.
Elovainio, Marko; Sommerlad, Andrew; Hakulinen, Christian; Pulkki-Råback, Laura; Virtanen, Marianna; Kivimäki, Mika; Singh-Manoux, Archana
2017-11-07
Social relations are important for health, particularly at older ages. We examined the salience of frequency of social contacts and marital status for cognitive ageing trajectories over 21 years, from midlife to early old age. Data are from the Whitehall II cohort study, including 4290 men and 1776 women aged 35-55 years at baseline (1985-88). Frequency of social contacts and marital status were measured in 1985-88 and 1989-90. Assessment of cognitive function on five occasions (1991-94, 1997-99, 2003-04, 2007-09 and 2012-13) included the following tests: short-term memory, inductive reasoning, verbal fluency (phonemic and semantic) and a combined global score. Cognitive trajectories over the study period were analysed using longitudinal latent growth class analyses, and the associations of these latent classes (trajectory memberships) with social relations were analysed using multinominal logistic regression. More frequent social contacts [relative risk (RRR) 0.96, 95% confidence interval (CI) 0.94 - 0.98] and being married (RRR 0.70, 95% CI 0.58 - 0.84) were associated with lower probability of being on a low rather than high cognitive performance trajectory over the subsequent 21 years. These associations persisted after adjustment for covariates. Of the sub-tests, social relations variables had the strongest association with phonemic fluency (RRR 0.95, 95% CI 0.94 - 0.97 for frequent contact; RRR 0.59, 95% CI 0.48 - 0.71 for being married). More frequent social contacts and having a spouse were associated with more favourable cognitive ageing trajectories. Further studies are needed to examine whether interventions designed to improve social connections affect cognitive ageing. © The Author 2017; all rights reserved. Published by Oxford University Press on behalf of the International Epidemiological Association
Carbonne, A; Thiolet, J M; Fournier, S; Fortineau, N; Kassis-Chikhani, N; Boytchev, I; Aggoune, M; Seguier, J C; Senechal, H; Tavolacci, M P; Coignard, B; Astagneau, P; Jarlier, V
2010-12-02
An outbreak of Klebsiella pneumoniae carbapenemase (KPC)-producing Klebsiella pneumoniae type 2 was detected in September 2009 in two hospitals in a suburb south of Paris, France. In total, 13 KPC-producing K. pneumoniae type 2 cases (four with infections and nine with digestive-tract colonisations) were identified, including a source case transferred from a Greek hospital. Of the 13 cases, seven were secondary cases associated with use of a contaminated duodenoscope used to examine the source case (attack rate: 41%) and five were secondary cases associated with patient-to-patient transmission in hospital. All isolated strains from the 13 patients: (i) exhibited resistance to all antibiotics except gentamicin and colistin, (ii) were more resistant to ertapenem (minimum inhibitory concentration (MIC) always greater than 4 mg/L) than to imipenem (MIC: 1–8 mg/L, depending on the isolate), (iii) carried the blaKPC-2 and blaSHV12 genes and (iv) had an indistinguishable pulsed-field gel electrophoresis (PFGE) pattern. These cases occurred in three hospitals: some were transferred to four other hospitals. Extended infection control measures implemented in the seven hospitals included: (i) limiting transfer of cases and contact patients to other wards, (ii) cohorting separately cases and contact patients, (iii) reinforcing hand hygiene and contact precautions and (iv) systematic screening of contact patients. Overall, 341 contact patients were screened. A year after the outbreak, no additional case has been identified in these seven hospitals. This outbreak emphasises the importance of rapid identification and notification of emerging highly resistant K. pneumoniae strains in order to implement reinforced control measures.
Oka, Saori; Wakui, Junichi; Ikeda, Shinobu; Yanagimoto, Shin; Kishimoto, Seishi; Gokoh, Maiko; Nasui, Miwako; Sugiura, Takayuki
2006-12-15
The possible involvement of 2-arachidonoylglycerol (2-AG), an endogenous ligand for the cannabinoid receptors (CB1 and CB2), in contact dermatitis in mouse ear was investigated. We found that the level of 2-AG was markedly elevated in the ear following a challenge with oxazolone in sensitized mice. Of note, the swelling following the challenge was suppressed by either the administration of SR144528, a CB2 receptor antagonist, immediately after sensitization, or the administration of SR144528 upon the challenge. The effect of AM251, a CB1 receptor antagonist, was marginal in either case. It seems apparent, therefore, that the CB2 receptor and its endogenous ligand 2-AG are closely involved in both the sensitization phase and the elicitation phase of oxazolone-induced contact dermatitis. In line with this, we found that Langerhans cells (MHC class II(+)) contain a substantial amount of CB2 receptor mRNA, whereas keratinocytes (MHC class II(-)) do not. We also obtained evidence that the expression of mRNAs for proinflammatory cytokines following a challenge with oxazolone was markedly suppressed by treatment with SR144528. We next examined whether the CB2 receptor and 2-AG participate in chronic contact dermatitis accompanied by the infiltration of tissues by eosinophils. The amount of 2-AG in mouse ear dramatically increased following repeated challenge with oxazolone. Importantly, treatment with SR144528 attenuated both the recruitment of eosinophils and ear swelling in chronic contact dermatitis induced by repeated challenge with oxazolone. These results strongly suggest that the CB2 receptor and 2-AG play important stimulative roles in the sensitization, elicitation, and exacerbation of allergic inflammation.
Kuchin, I; Starov, V
2015-05-19
A theory of contact angle hysteresis of liquid droplets on smooth, homogeneous solid substrates is developed in terms of the shape of the disjoining/conjoining pressure isotherm and quasi-equilibrium phenomena. It is shown that all contact angles, θ, in the range θr < θ < θa, which are different from the unique equilibrium contact angle θ ≠ θe, correspond to the state of slow "microscopic" advancing or receding motion of the liquid if θe < θ < θa or θr < θ < θe, respectively. This "microscopic" motion almost abruptly becomes fast "macroscopic" advancing or receding motion after the contact angle reaches the critical values θa or θr, correspondingly. The values of the static receding, θr, and static advancing, θa, contact angles in cylindrical capillaries were calculated earlier, based on the shape of disjoining/conjoining pressure isotherm. It is shown now that (i) both advancing and receding contact angles of a droplet on a on smooth, homogeneous solid substrate can be calculated based on shape of disjoining/conjoining pressure isotherm, and (ii) both advancing and receding contact angles depend on the drop volume and are not unique characteristics of the liquid-solid system. The latter is different from advancing/receding contact angles in thin capillaries. It is shown also that the receding contact angle is much closer to the equilibrium contact angle than the advancing contact angle. The latter conclusion is unexpected and is in a contradiction with the commonly accepted view that the advancing contact angle can be taken as the first approximation for the equilibrium contact angle. The dependency of hysteresis contact angles on the drop volume has a direct experimental confirmation.
Design rules for vertical interconnections by reverse offset printing
NASA Astrophysics Data System (ADS)
Kusaka, Yasuyuki; Kanazawa, Shusuke; Ushijima, Hirobumi
2018-03-01
Formation of vertical interconnections by reverse offset printing was investigated, particularly focusing on the transfer step, in which an ink pattern is transferred from a polydimethylsiloxane (PDMS) sheet for the step coverage of contact holes. We systematically examined the coverage of contact holes made of a tapered photoresist layer by varying the hole size, the hole depth, PDMS elasticity, PDMS thickness, printing speed, and printing indentation depth. Successful ink filling was achieved when the PDMS was softer, and the optimal PDMS thickness varied depending on the size of the contact holes. This behaviour is related to the bell-type uplift deformation of incompressible PDMS, which can be described by contact mechanics numerical simulations. Based on direct observation of PDMS/resist-hole contact behaviour, the step coverage of contact holes typically involves two steps of contact area growth: (i) the PDMS first touches the bottom of the holes and then (ii) the contact area gradually and radially widens toward the tapered sidewall. From an engineering perspective, it is pointed out that mechanical synchronisation mismatch in the roll-to-sheet type printing invokes the cracking of ink layers at the edges of contact holes. According to the above design rule, ink filling into a contact hole with thickness of 2.5 µm and radius of 10 µm was achieved. Contact chain patterns with 1386 points of vertical interconnections with the square hole size of up to 10 µm successfully demonstrated the validity of the technique presented herein.
How pinning and contact angle hysteresis govern quasi-static liquid drop transfer.
Chen, H; Tang, T; Zhao, H; Law, K-Y; Amirfazli, A
2016-02-21
This paper presents both experimental and numerical simulations of liquid transfer between two solid surfaces with contact angle hysteresis (CAH). Systematic studies on the role of the advancing contact angle (θa), receding contact angle (θr) and CAH in determining the transfer ratio (volume of the liquid transferred onto the acceptor surface over the total liquid volume) and the maximum adhesion force (Fmax) were performed. The transfer ratio was found to be governed by contact line pinning at the end of the transfer process caused by CAH of surfaces. A map based on θr of the two surfaces was generated to identify the three regimes for liquid transfer: (I) contact line pinning occurs only on the donor surface, (II) contact line pinning occurs on both surfaces, and (III) contact line pinning occurs only on the acceptor surface. With this map, an empirical equation is provided which is able to estimate the transfer ratio by only knowing θr of the two surfaces. The value of Fmax is found to be strongly influenced by the contact line pinning in the early stretching stage. For symmetric liquid bridges between two identical surfaces, Fmax may be determined only by θa, only by θr, or by both θa and θr, depending on the magnitude of the contact angles. For asymmetric bridges, Fmax is found to be affected by the period when contact lines are pinned on both surfaces.
Feinauer, Christoph; Procaccini, Andrea; Zecchina, Riccardo; Weigt, Martin; Pagnani, Andrea
2014-01-01
In the course of evolution, proteins show a remarkable conservation of their three-dimensional structure and their biological function, leading to strong evolutionary constraints on the sequence variability between homologous proteins. Our method aims at extracting such constraints from rapidly accumulating sequence data, and thereby at inferring protein structure and function from sequence information alone. Recently, global statistical inference methods (e.g. direct-coupling analysis, sparse inverse covariance estimation) have achieved a breakthrough towards this aim, and their predictions have been successfully implemented into tertiary and quaternary protein structure prediction methods. However, due to the discrete nature of the underlying variable (amino-acids), exact inference requires exponential time in the protein length, and efficient approximations are needed for practical applicability. Here we propose a very efficient multivariate Gaussian modeling approach as a variant of direct-coupling analysis: the discrete amino-acid variables are replaced by continuous Gaussian random variables. The resulting statistical inference problem is efficiently and exactly solvable. We show that the quality of inference is comparable or superior to the one achieved by mean-field approximations to inference with discrete variables, as done by direct-coupling analysis. This is true for (i) the prediction of residue-residue contacts in proteins, and (ii) the identification of protein-protein interaction partner in bacterial signal transduction. An implementation of our multivariate Gaussian approach is available at the website http://areeweb.polito.it/ricerca/cmp/code. PMID:24663061
Simplified fatigue life analysis for traction drive contacts
NASA Technical Reports Server (NTRS)
Rohn, D. A.; Loewenthal, S. H.; Coy, J. J.
1980-01-01
A simplified fatigue life analysis for traction drive contacts of arbitrary geometry is presented. The analysis is based on the Lundberg-Palmgren theory used for rolling-element bearings. The effects of torque, element size, speed, contact ellipse ratio, and the influence of traction coefficient are shown. The analysis shows that within the limits of the available traction coefficient, traction contacts exhibit longest life at high speeds. Multiple, load-sharing roller arrangements have an advantageous effect on system life, torque capacity, power-to-weight ratio and size.
Bis(tetramethylammonium) tetrachloridozincate(II), phase VI
Curtiss, Ashley B. S.; Musie, Ghezai T.; Powell, Douglas R.
2008-01-01
Phase VI of bis(tetramethylammonium) tetrachlorozincate(II), (C4H12N)2[ZnCl4], contains three formula units per asymmetric unit. Several short C—H⋯Cl contacts [2.70 (3) and 2.72 (4) Å] are observed, but they are believed to participate only in van der Waals interactions. The crystal studied exhibited inversion twinning. PMID:21200531
Process for forming shaped group II-VI semiconductor nanocrystals, and product formed using process
Alivisatos, A. Paul; Peng, Xiaogang; Manna, Liberato
2001-01-01
A process for the formation of shaped Group II-VI semiconductor nanocrystals comprises contacting the semiconductor nanocrystal precursors with a liquid media comprising a binary mixture of phosphorus-containing organic surfactants capable of promoting the growth of either spherical semiconductor nanocrystals or rod-like semiconductor nanocrystals, whereby the shape of the semiconductor nanocrystals formed in said binary mixture of surfactants is controlled by adjusting the ratio of the surfactants in the binary mixture.
Rudolph, Michael J.; Cassidy, Michael S.; Rong, Yinghui
2017-01-01
Ricin toxin is a heterodimer consisting of RTA, a ribosome-inactivating protein, and RTB, a lectin that facilitates receptor-mediated uptake into mammalian cells. In previous studies, we demonstrated that toxin-neutralizing antibodies target four spatially distinct hot spots on RTA, which we refer to as epitope clusters I–IV. In this report, we identified and characterized three single domain camelid antibodies (VHH) against cluster II. One of these VHHs, V5E1, ranks as one of the most potent ricin-neutralizing antibodies described to date. We solved the X-ray crystal structures of each of the three VHHs (E1, V1C7, and V5E1) in complex with RTA. V5E1 buries a total of 1,133 Å2 of surface area on RTA and makes primary contacts with α-helix A (residues 18–32), α-helix F (182–194), as well as the F-G loop. V5E1, by virtue of complementarity determining region 3 (CDR3), may also engage with RTB and potentially interfere with the high affinity galactose-recognition element that plays a critical role in toxin attachment to cell surfaces and intracellular trafficking. The two other VHHs, E1 and V1C7, bind epitopes adjacent to V5E1 but display only weak toxin neutralizing activity, thereby providing structural insights into specific residues within cluster II that may be critical contact points for toxin inactivation. PMID:27903650
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wellman, Dawn M.; Mattigod, Shas V.; Parker, Kent E.
2006-03-20
Nanoporous tin (II/IV) phosphate materials, with spherical morphology, have been synthesized using cetyltrimethylammonium chloride (CH3(CH2)15N(CH3)3Cl) as the surfactant. The structure of the material is stable at 500°C; however, partial oxidation of the material occurs with redox conversion of Sn2+ to Sn4+, resulting in a mixed Sn(II)/ Sn(IV) material. Preliminary batch contact studies were conducted to assess the effectiveness of nanoporous tin phosphate, NP-SnPO, in sequestering redox sensitive metals and radionuclides, technetium(VII), neptunium(V), thorium(IV), and a toxic metal, chromium(VI), from aqueous matrices. Results indicate tin (II) phosphate removed > 95% of all contaminants investigated from solution.
Investigations of Heavy Metal Ion Sorption Using Nanocomposites of Iron-Modified Biochar
NASA Astrophysics Data System (ADS)
Kołodyńska, D.; Bąk, J.; Kozioł, M.; Pylypchuk, L. V.
2017-06-01
Magnetic biochar nanocomposites were obtained by modification of biochar by zero-valent iron. The article provides information on the impact of contact time, initial Cd(II), Co(II), Zn(II), and Pb(II) ion concentrations, dose of the sorbents, solution pH and temperature on the adsorption capacity. On the basis of experiments, it was found that the optimum parameters for the sorption process are phase contact time 360 min (after this time, the equilibrium of all concentrations is reached), the dose of sorbent equal to 5 g/dm3, pH 5 and the temperature 295 K. The values of parameters calculated from the kinetic models and isotherms present the best match to the pseudo second order and Langmuir isotherm models. The calculated thermodynamic parameters ΔH 0, ΔS 0 and ΔG 0 indicate that the sorption of heavy metal ions is an exothermic and spontaneous process as well as favoured at lower temperatures, suggesting the physical character of sorption. The solution of nitric acid(V) at the concentration 0.1 mol/dm3 was the best acidic desorbing agent used for regeneration of metal-loaded magnetic sorbents. The physicochemical properties of synthesized composites were characterized by FTIR, SEM, XRD, XPS and TG analyses. The point characteristics of the double layer for biochar pHPZC and pHIEP were designated.
Biosorption of Fe(II) and Mn(II) Ions from Aqueous Solution by Rice Husk Ash
Zhao, Jiaying; Jiang, Zhao; Shan, Dexin; Lu, Yan
2014-01-01
Rice husk ash (RHA), an agricultural waste, was used as biosorbent for the removal of Iron(II) and Manganese(II) ions from aqueous solutions. The structural and morphological characteristics of RHA and its elemental compositions before and after adsorption of Fe(II) and Mn(II) were determined by scanning electron microscopic (SEM) and X-ray fluorescence (XRF) analyses. Batch experiments were carried out to determine the influence of initial pH, contact time, adsorbent dosage, and initial concentration on the removal of Fe(II) and Mn(II) ions. Langmuir, Freundlich, and Dubinin-Radushkevich (D-R) models were applied to describe the biosorption isotherm of the metal ions by RHA. The correlation coefficient (R 2) of Langmuir and Freundlich isotherm models equals 0.995 and 0.901 for Fe(II), 0.9862 and 0.8924 for Mn(II), respectively, so the Langmuir model fitted the equilibrium data better than the Freundlich isotherm model. The mean free energy values evaluated from the D-R model indicated that the biosorption of Fe(II) and Mn(II) onto RHA was physical in nature. Experimental data also showed that the biosorption processes of both metal ions complied with the pseudo-second-order kinetics. PMID:24982918
Removal of some metal ions by activated carbon prepared from Phaseolus aureus hulls.
Rao, M Madhava; Ramana, D K; Seshaiah, K; Wang, M C; Chien, S W Chang
2009-07-30
Removal of lead [Pb(II)], zinc [Zn(II)], copper [Cu(II)], and cadmium [Cd(II)] from aqueous solutions using activated carbon prepared from Phaseolus aureus hulls (ACPAH), an agricultural waste was studied. The influence of various parameters such as effect of pH, contact time, adsorbent dose, and initial concentration of metal ions on the removal was evaluated by batch method. The removal of metal ions by ACPAH was pH dependent and the optimum pH values were 7.0, 8.0, 7.0 and 6.0 for Cu(II), Cd(II), Zn(II), and Pb(II), respectively. The sorption isotherms were studied using Langmuir, Freundlich, Dubinin-Radushkevich (D-R), and Temkin isotherm models. The maximum adsorption capacity values of ACPAH for metal ions were 21.8 mg g(-1) for Pb(II), 21.2 mg g(-1) for Zn(II), 19.5 mg g(-1) for Cu(II), and 15.7 mg g(-1) for Cd(II). The experiments demonstrated that the removal of metal ions followed the pseudo-second-order kinetic model. Desorption experiments were carried out using HCl solution with a view to regenerate the spent adsorbent and to recover the adsorbed metal ions.
42 CFR 460.32 - Content and terms of PACE program agreement.
Code of Federal Regulations, 2012 CFR
2012-10-01
... phone number of the program director. (ii) Name of all governing body members. (iii) Name and phone number of a contact person for the governing body. (5) A participant bill of rights approved by CMS and...
42 CFR 460.32 - Content and terms of PACE program agreement.
Code of Federal Regulations, 2014 CFR
2014-10-01
... phone number of the program director. (ii) Name of all governing body members. (iii) Name and phone number of a contact person for the governing body. (5) A participant bill of rights approved by CMS and...
42 CFR 460.32 - Content and terms of PACE program agreement.
Code of Federal Regulations, 2013 CFR
2013-10-01
... phone number of the program director. (ii) Name of all governing body members. (iii) Name and phone number of a contact person for the governing body. (5) A participant bill of rights approved by CMS and...
75 FR 18216 - National Institute of Biomedical Imaging and Bioengineering; Notice of Closed Meeting
Federal Register 2010, 2011, 2012, 2013, 2014
2010-04-09
..., Democracy II, 6707 Democracy Blvd, Suite 900, Bethesda, MD 20892. Contact Person: John K. Hayes, PhD, Scientific Review Officer, 6707 Democracy Boulevard, Suite 959, Democracy Two, Bethesda, MD 20892, 301-451...
Kumar, Ilango Aswin; Viswanathan, Natrayasamy
2018-03-01
A tetra-amine copper(II) chitosan bead system (TAC@CS composite beads) was developed by grafting tetra-amine copper(II) (TAC) with chitosan (CS) and utilized for phosphate removal. The prepared TAC@CS composite beads possess enhanced phosphate sorption capacity (SC) of 41.42 ± 0.071 mg/g than copper grafted chitosan (Cu@CS) composite, TAC and chitosan which were found to be 37.01 ± 0.803, 33.20 ± 0.650 and 7.24 ± 0.059 mg/g respectively. In batch mode, various adsorption influencing parameters like contact time, initial phosphate concentration, solution pH, co-anions and temperature were optimized for maximum phosphate sorption. The prepared adsorbents were characterized by FTIR, XRD, UV-Visible, SEM and EDAX analysis. The adsorption isotherms and thermodynamic parameters of the adsorbent were studied. The feasible phosphate uptake mechanism of TAC@CS biocomposite beads was reported. The reusability studies of TAC@CS composite beads were carried out using NaOH as elutant. The suitability of TAC@CS composite beads at field conditions was tested with phosphate contaminated field water samples collected from nearby areas of Dindigul district. Copyright © 2017 Elsevier Ltd. All rights reserved.
Lead removal by Spirulina platensis biomass.
Al-Homaidan, Ali A; Al-Abbad, Aljawharah F; Al-Hazzani, Amal A; Al-Ghanayem, Abdullah A; Alabdullatif, Jamila A
2016-01-01
In this investigation, we report on the biosorption of Pb (II) from aqueous solutions by the nonliving biomass of the micro-alga (cyanobacterium) Spirulina platensis. Propagation of the micro-alga was carried out in outside oblong raceway ponds. The biomass was cleaned, dried and used for the investigation. The effects of pH, adsorbent dose, temperature, initial concentration of Pb (II), and contact time on the adsorption of lead by the dry biomass were studied. The experiments were carried out in 250 ml conical flasks containing 100 ml of test solutions using an orbital incubator at 150 rpm. Concentrations of the metal before and after the experiments were measured using Atomic Absorption Spectrophotometer. Very high levels of Pb (II) removal (>91%) were obtained. The optimum conditions for maximal adsorption by S. platensis were found to be pH 3; 2 g of adsorbent dose; incubation at 26°C; 100 mg/l of lead initial concentration and 60 minutes of contact time. The experimental data fitted well with Freundlich isotherm equation with R(2) values greater than 0.97. Based on our results, we recommend the utilization of S. platensis biomass for heavy metal removal from aqueous solutions.
Frith, Lucy; Blyth, Eric; Lui, Steve
2017-05-01
What contact arrangements are established between providers and recipients of embryos using Snowflakes® Embryo Adoption Program? Contact arrangements varied considerably and were generally positively described, although some challenges were acknowledged. Reproductive technologies create new and diverse family forms, and the ways in which families created by embryo adoption are negotiated in practice have not been extensively investigated. This exploratory, mixed-methods study had two phases: (i) an online survey (open May-September 2013) and (ii) qualitative semi-structured interviews by email (conducted between 2014 and 2015), exploring participants' experiences of contact with their embryo provider or recipient. Phase I included 17 providers (14 women and 3 men) and 28 recipients (27 women and 1 man). Phase II included 8 providers (5 women and 3 men) and 12 recipients (10 women and 2 men). All participants, except one, were located in the US. This study illustrates how embryo adoption in the US, as a form of conditional donation, can operate and how the participants define and negotiate these emerging relationships. All families were open with their children about how they were conceived and early contact between recipients and providers (frequently before birth) was valued. On the whole, participants were happy with the amount and type of contact they had, and where the current contact did not involve the children, it was seen as a way of keeping the channels open for future contact when the children were older. Participants often portrayed the opportunities for contact as being in the best interests of the child. The study participants are a particular group who had chosen to either receive or give their embryos via a conditional embryo adoption agency in the US and had established contact. Therefore, this is not a representative sample of those who provide or receive embryos for family building. This embryo adoption model clearly fulfils a need; some people want to use a conditional embryo donation programme such as Snowflakes®. Some form of 'ongoing support mechanism' such as counselling could be useful for those negotiating the complex sets of new kinship patterns and balancing these relationships with their children's welfare. The authors have no conflict of interest to declare. Snowflakes is a commercial adoption agency and the authors have no relation to the organization, other than requesting that they participate in this research project. N/A. © The Author 2017. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com
Binding Modes of Teixobactin to Lipid II: Molecular Dynamics Study.
Liu, Yang; Liu, Yaxin; Chan-Park, Mary B; Mu, Yuguang
2017-12-08
Teixobactin (TXB) is a newly discovered antibiotic targeting the bacterial cell wall precursor Lipid II (L II ). In the present work, four binding modes of TXB on L II were identified by a contact-map based clustering method. The highly flexible binary complex ensemble was generated by parallel tempering metadynamics simulation in a well-tempered ensemble (PTMetaD-WTE). In agreement with experimental findings, the pyrophosphate group and the attached first sugar subunit of L II are found to be the minimal motif for stable TXB binding. Three of the four binding modes involve the ring structure of TXB and have relatively higher binding affinities, indicating the importance of the ring motif of TXB in L II recognition. TXB-L II complexes with a ratio of 2:1 are also predicted with configurations such that the ring motif of two TXB molecules bound to the pyrophosphate-MurNAc moiety and the glutamic acid residue of one L II , respectively. Our findings disclose that the ring motif of TXB is critical to L II binding and novel antibiotics can be designed based on its mimetics.
Lass, Christian; Vocanson, Marc; Wagner, Steffen; Schempp, Christoph M; Nicolas, Jean-Francois; Merfort, Irmgard; Martin, Stefan F
2008-10-01
Sesquiterpene lactones (SL), secondary plant metabolites from flowerheads of Arnica, exert anti-inflammatory effects mainly by preventing nuclear factor (NF)-kappaB activation because of alkylation of the p65 subunit. Despite its known immunosuppressive action, Arnica has been classified as a plant with strong potency to induce allergic contact dermatitis. Here we examined the dual role of SL as anti-inflammatory compounds and contact allergens in vitro and in vivo. We tested the anti-inflammatory and allergenic potential of SL in the mouse contact hypersensitivity model. We also used dendritic cells to study the activation of NF-kappaB and the secretion of interleukin (IL)-12 in the presence of different doses of SL in vitro. Arnica tinctures and SL potently suppressed NF-kappaB activation and IL-12 production in dendritic cells at high concentrations, but had immunostimulatory effects at low concentrations. Contact hypersensitivity could not be induced in the mouse model, even when Arnica tinctures or SL were applied undiluted to inflamed skin. In contrast, Arnica tinctures suppressed contact hypersensitivity to the strong contact sensitizer trinitrochlorobenzene and activation of dendritic cells. However, contact hypersensitivity to Arnica tincture could be induced in acutely CD4-depleted MHC II knockout mice. These results suggest that induction of contact hypersensitivity by Arnica is prevented by its anti-inflammatory effect and immunosuppression as a result of immune regulation in immunocompetent mice.
NASA Astrophysics Data System (ADS)
Indhumathi, Ponnuswamy; Sathiyaraj, Subbaiyan; Koelmel, Jeremy P.; Shoba, Srinivasan U.; Jayabalakrishnan, Chinnasamy; Saravanabhavan, Munusamy
2018-05-01
The ability of green micro algae Chlorella vulgaris for biosorption of Cu(II) ions from an aqueous solution was studied. The biosorption process was affected by the solution pH, contact time, temperature and initial Cu(II) concentration. Experimental data were analyzed in terms of pseudo-first order, pseudo-second order and intra particle diffusion models. Results showed that the sorption process of Cu(II) ions followed pseudo-second order kinetics. The sorption data of Cu(II) ions are fitted to Langmuir, Freundlich, and Redlich-Peterson isotherms, and the Temkin isotherm. The thermodynamic study shows the Cu(II) biosorption was exothermic in nature. The Cu(II) ions were recovered effectively from Chlorella vulgaris biomass using 0.1 M H2SO4 with up to 90.3% recovery, allowing for recycling of the Cu. Green algae from freshwater bodies showed significant potential for Cu(II) removal and recovery from industrial wastewater.
Martín-Gonzalo, Juan Andrés; Rodríguez-Andonaegui, Irene; López-López, Javier; Pascual-Pascual, Samuel Ignacio
2018-01-01
The Hereditary Spastic Paraplegias (HSP) are a group of heterogeneous disorders with a wide spectrum of underlying neural pathology, and hence HSP patients express a variety of gait abnormalities. Classification of these phenotypes may help in monitoring disease progression and personalizing therapies. This is currently managed by measuring values of some kinematic and spatio-temporal parameters at certain moments during the gait cycle, either in the doctor´s surgery room or after very precise measurements produced by instrumental gait analysis (IGA). These methods, however, do not provide information about the whole structure of the gait cycle. Classification of the similarities among time series of IGA measured values of sagittal joint positions throughout the whole gait cycle can be achieved by hierarchical clustering analysis based on multivariate dynamic time warping (DTW). Random forests can estimate which are the most important isolated parameters to predict the classification revealed by DTW, since clinicians need to refer to them in their daily practice. We acquired time series of pelvic, hip, knee, ankle and forefoot sagittal angular positions from 26 HSP and 33 healthy children with an optokinetic IGA system. DTW revealed six gait patterns with different degrees of impairment of walking speed, cadence and gait cycle distribution and related with patient’s age, sex, GMFCS stage, concurrence of polyneuropathy and abnormal visual evoked potentials or corpus callosum. The most important parameters to differentiate patterns were mean pelvic tilt and hip flexion at initial contact. Longer time of support, decreased values of hip extension and increased knee flexion at initial contact can differentiate the mildest, near to normal HSP gait phenotype and the normal healthy one. Increased values of knee flexion at initial contact and delayed peak of knee flexion are important factors to distinguish GMFCS stages I from II-III and concurrence of polyneuropathy. PMID:29518090
Pressure Contact Sounding Data for NASA's Atmospheric Variability Experiment (AVE 3)
NASA Technical Reports Server (NTRS)
Fuelberg, H. E.; Hill, C. K.; Turner, R. E.; Long, K. E.
1975-01-01
The basic rawinsonde data are described at each pressure contact from the surface to sounding termination for the 41 stations participating in the AVE III measurement program that began at 0000 GMT on February 6 and ended at 1200 GMT on February 7, 1975. Soundings were taken at 3-hour intervals during a large period of the experiment from most stations within the United States east of about 105 degrees west longitude. Methods of data processing, change in reduction scheme since the AVE II pilot experiment, and data accuracy are briefly discussed. An example of contact data is presented, and microfiche cards of all the contact data are included in the appendix. The AVE III project was conducted to better understand and establish the extent of applications for meteorological satellite sensor data through correlative ground truth experiments and to provide basic experimental data for use in studies of atmospheric scales of-motion interrelationships.
Allergic contact dermatitis to fragrances: part 2.
Arribas, M P; Soro, P; Silvestre, J F
2013-01-01
Allergic contact dermatitis due to fragrances usually manifests as subacute or chronic dermatitis because fragrances are found in a wide range of products to which patients are repeatedly exposed. The typical patient is a middle-aged woman with dermatitis on her hands and face, although other sites may be affected depending on the allergen and the product in which it is found. The standard patch test series of the Spanish Contact Dermatitis and Skin Allergy Research Group (GEIDAC) contains 4 fragrance markers: balsam of Peru, fragrance mix i, fragrance mix ii, and lyral. Testing with a specific fragrance series is recommended in patients with a positive result to any of these 4 markers. The use of a specific fragrance series and new legislation obliging manufacturers to specify the fragrances used in their products, will help to improve the management of allergic contact dermatitis due to fragrances. Copyright © 2012 Elsevier España, S.L. and AEDV. All rights reserved.
Traveling-wave piezoelectric linear motor part II: experiment and performance evaluation.
Ting, Yung; Li, Chun-Chung; Chen, Liang-Chiang; Yang, Chieh-Min
2007-04-01
This article continues the discussion of a traveling-wave piezoelectric linear motor. Part I of this article dealt with the design and analysis of the stator of a traveling-wave piezoelectric linear motor. In this part, the discussion focuses on the structure and modeling of the contact layer and the carriage. In addition, the performance analysis and evaluation of the linear motor also are dealt with in this study. The traveling wave is created by stator, which is constructed by a series of bimorph actuators arranged in a line and connected to form a meander-line structure. Analytical and experimental results of the performance are presented and shown to be almost in agreement. Power losses due to friction and transmission are studied and found to be significant. Compared with other types of linear motors, the motor in this study is capable of supporting heavier loads and provides a larger thrust force.
Huang, Linxian; Li, Meilin; Si, Guangchao; Wei, Jinglin; Ngo, Huu Hao; Guo, Wenshan; Xu, Weiying; Du, Bin; Wei, Qin; Wei, Dong
2018-05-18
In the present study, the responses of microbial products in the biosorption process of Cu(II) onto aerobic granular sludge were evaluated by using batch and spectroscopic approaches. Batch experimental data showed that extracellular polymeric substances (EPSs) contributed to Cu(II) removal from an aqueous solution, especially when treating low metal concentrations, whereas soluble microbial products (SMPs) were released under the metal stress during biosorption process. A three-dimensional excitation-emission matrix (3D-EEM) identified four main fluorescence peaks in the EPS, i.e., tryptophan protein-like, aromatic protein-like, humic-like and fulvic acid-like substances, and their fluorescence intensities decreased gradually in the presence of Cu(II) during the sorption process. Particularly, tryptophan protein-like substances quenched the Cu(II) binding to a much higher extent through a static quenching process with less than one class of binding sites. According to the synchronous fluorescence spectra, the whole fluorescence intensity of released SMP samples expressed an increased trend with different degrees along with contact time. Two-dimensional correlation spectroscopy (2D-COS) suggested that the fulvic-like fluorescence fraction might be more susceptible to metal exposure than other fractions. The result of molecular weight distribution demonstrated that the SMPs released from the biosorption process differed significantly according to contact time. The result obtained could provide new insights into the responses of microbial products from aerobic granular sludge with heavy metal treatment. Copyright © 2018. Published by Elsevier Inc.
A 3D contact analysis approach for the visualization of the electrical contact asperities
DOE Office of Scientific and Technical Information (OSTI.GOV)
Roussos, Constantinos C.; Swingler, Jonathan
The electrical contact is an important phenomenon that should be given into consideration to achieve better performance and long term reliability for the design of devices. Based upon this importance, the electrical contact interface has been visualized as a “3D Contact Map” and used in order to investigate the contact asperities. The contact asperities describe the structures above and below the contact spots (the contact spots define the 3D contact map) to the two conductors which make the contact system. The contact asperities require the discretization of the 3D microstructures of the contact system into voxels. A contact analysis approachmore » has been developed and introduced in this paper which shows the way to the 3D visualization of the contact asperities of a given contact system. For the discretization of 3D microstructure of contact system into voxels, X-ray Computed Tomography (CT) method is used in order to collect the data of a 250 V, 16 A rated AC single pole rocker switch which is used as a contact system for investigation.« less
A 3D contact analysis approach for the visualization of the electrical contact asperities
Swingler, Jonathan
2017-01-01
The electrical contact is an important phenomenon that should be given into consideration to achieve better performance and long term reliability for the design of devices. Based upon this importance, the electrical contact interface has been visualized as a ‘‘3D Contact Map’’ and used in order to investigate the contact asperities. The contact asperities describe the structures above and below the contact spots (the contact spots define the 3D contact map) to the two conductors which make the contact system. The contact asperities require the discretization of the 3D microstructures of the contact system into voxels. A contact analysis approach has been developed and introduced in this paper which shows the way to the 3D visualization of the contact asperities of a given contact system. For the discretization of 3D microstructure of contact system into voxels, X-ray Computed Tomography (CT) method is used in order to collect the data of a 250 V, 16 A rated AC single pole rocker switch which is used as a contact system for investigation. PMID:28105383
A 3D contact analysis approach for the visualization of the electrical contact asperities
Roussos, Constantinos C.; Swingler, Jonathan
2017-01-11
The electrical contact is an important phenomenon that should be given into consideration to achieve better performance and long term reliability for the design of devices. Based upon this importance, the electrical contact interface has been visualized as a “3D Contact Map” and used in order to investigate the contact asperities. The contact asperities describe the structures above and below the contact spots (the contact spots define the 3D contact map) to the two conductors which make the contact system. The contact asperities require the discretization of the 3D microstructures of the contact system into voxels. A contact analysis approachmore » has been developed and introduced in this paper which shows the way to the 3D visualization of the contact asperities of a given contact system. For the discretization of 3D microstructure of contact system into voxels, X-ray Computed Tomography (CT) method is used in order to collect the data of a 250 V, 16 A rated AC single pole rocker switch which is used as a contact system for investigation.« less
Desmoplakin II expression is not restricted to stratified epithelia.
Angst, B D; Nilles, L A; Green, K J
1990-10-01
Desmosomes are major intercellular junctions found in association with intermediate filaments in epithelial, cardiac and arachnoidal tissue. Desmoplakins I and II (DPI and II) are highly related proteins localized in the innermost part of the desmosomal plaque and are candidates for linking intermediate filaments (IF) to the desmosomal complex. While investigators agree that DPI is present in all epithelia, they disagree on the distribution of DPII. Some have reported DPII to be restricted to stratified tissue and have furthermore suggested that the expression of DPII may be linked to stratification. We have compared the expression of DPI and II at the mRNA and protein levels in cell lines derived from simple, transitional and stratified epithelia. Northern blot analysis revealed DPI and II mRNA to be present in all cell lines as well as simple and stratified epithelial tissues. However, DPII mRNA could not be detected in cardiac muscle tissue. Immunoblotting and immunoprecipitation demonstrated the presence of DPI and II in all cell lines at the whole-cell protein level as well as in association with cytoskeletal fractions. Immunofluorescence staining was used to correlate the biochemical findings with the localization of DPI and II. While most cell lines exhibited typical intercellular and in many cases cytoplasmic DP staining, T24 cells exhibited predominantly diffuse and dotty cytoplasmic staining. In addition, we investigated whether changes in DPI and II expression occurred following calcium-induced cell contact formation and stratification in the human pharyngeal cell line, FaDu. No significant changes in mRNA or whole-cell protein levels were observed during a period of 5 days following the calcium switch. However, immunoblotting revealed a significant increase in DPI and II levels in the insoluble protein pool during desmosome formation. These observations indicated a possible recruitment of soluble DPI/II into an insoluble pool after induction of desmosome assembly by the calcium switch, consistent with earlier reports for MDCK cells. In summary, our results suggest that the expression of DPII is not strictly linked to stratification or differentiation; however, the apparent absence of DPII mRNA from cardiac muscle suggests it may not be a constituent of all desmosomes.
Li, Ronghua; Liang, Wen; Wang, Jim J; Gaston, Lewis A; Huang, Di; Huang, Hui; Lei, Shuang; Awasthi, Mukesh Kumar; Zhou, Baoyue; Xiao, Ran; Zhang, Zengqiang
2018-04-15
Enhancing the contaminant adsorption capacity is a key factor affecting utilization of carbon-based adsorbents in wastewater treatment and encouraging development of biomass thermo-disposal. In this study, a novel MgO hybrid sponge-like carbonaceous composite (HSC) derived from sugarcane leafy trash was prepared through an integrated adsorption-pyrolysis method. The resulted HSC composite was characterized and employed as adsorbent for the removal of negatively charged arsenate (As(V)), positively charged Pb(II), and the organic pollutant methylene blue (MB) from aqueous solutions in batch experiments. The effects of solution pH, contact time, initial concentration, temperature, and ionic strength on As(V), Pb(II) and MB adsorption were investigated. HSC was composed of nano-size MgO flakes and nanotube-like carbon sponge. Hybridization significantly improved As(V), Pb(II) and methylene blue (MB) adsorption when compared with the material without hybridization. The maximum As(V), Pb(II) and MB adsorption capacities obtained from Langmuir model were 157 mg/g, 103 mg/g and 297 mg/g, respectively. As(V) adsorption onto HSC was best fit by the pseudo-second-order model, and Pb(II) and MB with the intraparticle diffusion model. Increased temperature and ionic strength decreased Pb(II) and MB adsorption onto HSC more than As(V). Further FT-IR, XRD and XPS analysis demonstrated that the removal of As(V) by HSC was mainly dominated by surface deposition of MgHAsO 4 and Mg(H 2 AsO 4 ) 2 crystals on the HSC composite, while carbon π-π* transition and carbon π-electron played key roles in Pb(II) and MB adsorption. The interaction of Pb(II) with carbon matrix carboxylate was also evident. Overall, MgO hybridization improves the preparation of the nanotube-like carbon sponge composite and provides a potential agricultual residue-based adsorbent for As(V), Pb(II) and MB removal. Copyright © 2018 Elsevier Ltd. All rights reserved.
Nickel(II) biosorption from aqueous solutions by shrimp head biomass.
Hernández-Estévez, Alejandro; Cristiani-Urbina, Eliseo
2014-11-01
The present study evaluates the capacity of shrimp (Farfantepenaeus aztecus) head to remove toxic Ni(II) ions from aqueous solutions. Relevant parameters that could affect the biosorption process, such as shrimp head pretreatment, solution pH level, contact time and initial Ni(II) concentration, were studied in batch systems. An increase in Ni(II) biosorption capacity and a reduction in the time required to reach Ni(II) biosorption equilibrium was manifested by shrimp head biomass pretreated by boiling in 0.5 N NaOH for 15 min; this biomass was thereafter denominated APSH. The optimum biosorption level of Ni(II) ions onto APSH was observed at pH 7.0. Biosorption increased significantly with rising initial Ni(II) concentration. In terms of biosorption dynamics, the pseudo-second-order kinetic model described Ni(II) biosorption onto APSH best. The equilibrium data adequately fitted the Langmuir isotherm model within the studied Ni(II) ion concentration range. According to this isotherm model, the maximum Ni(II) biosorption capacity of APSH was 104.22 mg/g. Results indicate that APSH could be used as a low-cost, environmentally friendly, and promising biosorbent with high biosorption capacity to remove Ni(II) from aqueous solutions.
Do uniform tangential interfacial stresses enhance adhesion?
NASA Astrophysics Data System (ADS)
Menga, Nicola; Carbone, Giuseppe; Dini, Daniele
2018-03-01
We present theoretical arguments, based on linear elasticity and thermodynamics, to show that interfacial tangential stresses in sliding adhesive soft contacts may lead to a significant increase of the effective energy of adhesion. A sizable expansion of the contact area is predicted in conditions corresponding to such scenario. These results are easily explained and are valid under the assumptions that: (i) sliding at the interface does not lead to any loss of adhesive interaction and (ii) spatial fluctuations of frictional stresses can be considered negligible. Our results are seemingly supported by existing experiments, and show that frictional stresses may lead to an increase of the effective energy of adhesion depending on which conditions are established at the interface of contacting bodies in the presence of adhesive forces.
Afkhami, Abbas; Saber-Tehrani, Mohammad; Bagheri, Hasan
2010-09-15
2,4-Dinitrophenylhydrazine (DNPH) immobilized on sodium dodecyl sulfate coated nano-alumina was developed for the removal of metal cations Pb(II), Cd(II), Cr(III), Co(II), Ni(II) and Mn(II) from water samples. The research results displayed that adsorbent has the highest adsorption capacity for Pb(II), Cr(III) and Cd(II) in ions mixture system. Optimal experimental conditions including pH, adsorbent dosage and contact time have been established. Langmuir and Freundlich isotherm models were applied to analyze the experimental data. The best interpretation for the experimental data was given by the Freundlich adsorption isotherm equation for Mn(II), Pb(II), Cr(III) and Cd(II) ions and by Langmuir isotherm equation for Ni(II) and Co(II) ions. Desorption experiments by elution of the adsorbent with a mixture of nitric acid and methanol show that the modified alumina nanoparticles could be reused without significant losses of its initial properties even after three adsorption-desorption cycles. Thus, modified nano-alumina with DNPH is favorable and useful for the removal of these metal ions, and the high adsorption capacity makes it a good promising candidate material for Pb(II),Cr(III) and Cd(II) removal. Copyright 2010 Elsevier B.V. All rights reserved.
Analysis of rolling contact spall life in 440 C steel bearing rims
NASA Technical Reports Server (NTRS)
Bastias, P. C.; Bhargava, V.; Bower, A. P.; Du, J.; Gupta, V.; Hahn, G. T.; Kulkarni, S. M.; Kumar, A. M.; Leng, X.; Rubin, C. A.
1991-01-01
The results of a two year study of the mechanisms of spall failure in the HPOTP bearings are described. The objective was to build a foundation for detailed analyses of the contact life in terms of: cyclic plasticity, contact mechanics, spall nucleation, and spall growth. Since the laboratory rolling contact testing is carried out in the 3 ball/rod contact fatigue testing machine, the analysis of the contacts and contact lives produced in this machine received attention. The results from the experimentally observed growth lives are compared with calculated predictions derived from the fracture mechanics calculations.
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2010-03-04
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Generation of helical gears with new surfaces topology by application of CNC machines
NASA Technical Reports Server (NTRS)
Litvin, F. L.; Chen, N. X.; Hsiao, C. L.; Handschuh, Robert F.
1993-01-01
Analysis of helical involute gears by tooth contact analysis shows that such gears are very sensitive to angular misalignment that leads to edge contact and the potential for high vibration. A new topology of tooth surfaces of helical gears that enables a favorable bearing contact and a reduced level of vibration is described. Methods for grinding of the helical gears with the new topology are proposed. A TCA (tooth contact analysis) program for simulation of meshing and contact of helical gears with the new topology has been developed. Numerical examples that illustrate the proposed ideas are discussed.
Generation of helical gears with new surfaces, topology by application of CNC machines
NASA Technical Reports Server (NTRS)
Litvin, F. L.; Chen, N. X.; Hsiao, C. L.; Handschuh, R. F.
1993-01-01
Analysis of helical involute gears by tooth contact analysis shows that such gears are very sensitive to angular misalignment that leads to edge contact and the potential for high vibration. A new topology of tooth surfaces of helical gears that enables a favorable bearing contact and a reduced level of vibration is described. Methods for grinding of the helical gears with the new topology are proposed. A TCA (tooth contact analysis) program for simulation of meshing and contact of helical gears with the new topology has been developed. Numerical examples that illustrate the proposed ideas are discussed.
Computerized Design and Analysis of Face-Milled, Uniform Tooth Height Spiral Bevel Gear Drives
NASA Technical Reports Server (NTRS)
Litvin, Faydor L.; Wang, Anngwo; Handschuh, R. F.
1996-01-01
Face-milled spiral bevel gears with uniform tooth height are considered. An approach is proposed for the design of low noise and localized bearing contact of such gears. The approach is based on the mismatch of contacting surfaces and permits two types of bearing contact either directed longitudinally or across the surface to be obtained. A Tooth Contact Analysis (TCA) computer program was developed. This analysis was used to determine the influence of misalignment on meshing and contact of the spiral bevel gears. A numerical example that illustrates the developed theory is provided.
Palladium (II) catalyized polymerization of norbornene and acrylates
Sen, Ayusman; Kacker, Smita; Hennis, April; Polley, Jennifer D.
2000-08-29
Homopolymers or copolymers of acrylates, homopolymers or copolymers of norbornenes, and copolymers of acrylates with norbornenes, may be prepared by contacting acrylate and/or norbornene monomer reactant under polymerization conditions and in the presence of a solvent with a catalyst system consisting essentially of a Pd(II) dimer component having the formula: [(L)Pd(R)(X)].sub.2, where L is a monodentate phosphorus or nitrogen ligand, X is an anionic group, and R is an alkyl or aryl group.
(2,2′-Biquinoline-κ2 N,N′)dichloridoiron(II)
Rahimi, Narjes; Safari, Nasser; Amani, Vahid; Khavasi, Hamid Reza
2009-01-01
In the title compound, [FeCl2(C18H12N2)], the FeII atom is four-coordinated in a distorted tetrahedral arrangement by an N,N′-bidentate 2,2′-biquinoline ligand and two chloride ions. In the crystal, there are extensive π–π contacts between the pyridine rings [centroid–centroid distances = 3.7611 (3), 3.7603 (4), 3.5292 (4), 3.5336 (5) and 3.6656 (4) Å]. PMID:21578122
United States Air Force Summer Faculty Research Program (1987). Program Management Report.
1987-12-01
lllllll~hEEEI ,II .2 I. 1.25u 11111 1 1 MICROCOP RESOLUTION TES CHART 1% 0., :: nb- l q1 120 I iI UNITED STATES AIR FORCE SUMMER FACULTY RESEARCH...certain chemical compound , its pharmacological properties and the pathways of metabolism, absorption, distribution and excretion must be investigated, the...criteria can be recommended for personnel who handle or are otherwise in contact with such compounds . 5.0. r ,r,. -,&5 N The Toxic Hazards Division
Integral finite element analysis of turntable bearing with flexible rings
NASA Astrophysics Data System (ADS)
Deng, Biao; Liu, Yunfei; Guo, Yuan; Tang, Shengjin; Su, Wenbin; Lei, Zhufeng; Wang, Pengcheng
2018-03-01
This paper suggests a method to calculate the internal load distribution and contact stress of the thrust angular contact ball turntable bearing by FEA. The influence of the stiffness of the bearing structure and the plastic deformation of contact area on the internal load distribution and contact stress of the bearing is considered. In this method, the load-deformation relationship of the rolling elements is determined by the finite element contact analysis of a single rolling element and the raceway. Based on this, the nonlinear contact between the rolling elements and the inner and outer ring raceways is same as a nonlinear compression spring and bearing integral finite element analysis model including support structure was established. The effects of structural deformation and plastic deformation on the built-in stress distribution of slewing bearing are investigated on basis of comparing the consequences of load distribution, inner and outer ring stress, contact stress and other finite element analysis results with the traditional bearing theory, which has guiding function for improving the design of slewing bearing.
Mixed ternary heterojunction solar cell
Chen, Wen S.; Stewart, John M.
1992-08-25
A thin film heterojunction solar cell and a method of making it has a p-type layer of mixed ternary I-III-VI.sub.2 semiconductor material in contact with an n-type layer of mixed binary II-VI semiconductor material. The p-type semiconductor material includes a low resistivity copper-rich region adjacent the back metal contact of the cell and a composition gradient providing a minority carrier mirror that improves the photovoltaic performance of the cell. The p-type semiconductor material preferably is CuInGaSe.sub.2 or CuIn(SSe).sub.2.
Comparative in vitro encrustation studies of biomaterials in human urine.
Gleeson, M J; Glueck, J A; Feldman, L; Griffith, D P; Noon, G P
1989-01-01
A new dynamic in vitro human urine model was developed to compare biomaterial encrustation. The model incorporates a capacity to study seven biomaterials, a daily urine inflow of 500 ml, a reservoir capacity of 700 ml, and a turnover rate of four days. Encrustation studies performed for 2 weeks in sterile and infected (Proteus Vulgaris) urine on segmented polyether polyurethane, polyester polyurethane, silicone (Mitsui), silicone (Dow Corning), biothane, biolor 1 and biolor 11 demonstrated that biolor 11 (silicone-carbon composite) caused the least encrustation. Encrustation analysis showed brushite in the sterile model and struvite and ammonium acid urate in the infected mode I. Biolor II should have beneficial applications in catheters, stents and prosthetics which come in contact with urine.
Geomorphic Units on Titan: constraints on the origin of Undifferentiated Plains
NASA Astrophysics Data System (ADS)
Lopes, R. M. C.; Malaska, M. J.; Solomonidou, A.; LeGall, A.; Janssen, M. A.; Neish, C.; Turtle, E. P.; Birch, S. P. D.; Hayes, A. G.; Radebaugh, J.; Coustenis, A.
2015-10-01
We present the global distribution of the major classes of units and, where there are direct morphological contacts, describe how these classes of units relate to each other in terms of setting and emplacement history (Fig. 1). In particular, we focus on constraining the origin of the Undifferentiated Plains, which cover large expanses of Titan's surface (Fig. 2). We examined and evaluated different formation mechanisms, including (i) cryovolcanic origin, consisting of overlapping flows of low relief or (ii) sedimentary origins, resulting from fluvial/lacustrine or aeolian deposition, or accumulation of photolysis products created in the atmosphere. The results from our analysis suggest that a sedimentary origin is the most likely, with all the aforementioned processes possibly contributing.
Human tRNA genes function as chromatin insulators
Raab, Jesse R; Chiu, Jonathan; Zhu, Jingchun; Katzman, Sol; Kurukuti, Sreenivasulu; Wade, Paul A; Haussler, David; Kamakaka, Rohinton T
2012-01-01
Insulators help separate active chromatin domains from silenced ones. In yeast, gene promoters act as insulators to block the spread of Sir and HP1 mediated silencing while in metazoans most insulators are multipartite autonomous entities. tDNAs are repetitive sequences dispersed throughout the human genome and we now show that some of these tDNAs can function as insulators in human cells. Using computational methods, we identified putative human tDNA insulators. Using silencer blocking, transgene protection and repressor blocking assays we show that some of these tDNA-containing fragments can function as barrier insulators in human cells. We find that these elements also have the ability to block enhancers from activating RNA pol II transcribed promoters. Characterization of a putative tDNA insulator in human cells reveals that the site possesses chromatin signatures similar to those observed at other better-characterized eukaryotic insulators. Enhanced 4C analysis demonstrates that the tDNA insulator makes long-range chromatin contacts with other tDNAs and ETC sites but not with intervening or flanking RNA pol II transcribed genes. PMID:22085927
Delamination and Stitched Failure in Stitched Composite Joints
NASA Technical Reports Server (NTRS)
Glaessgen, E. H.; Raju, I. S.; Poe, C. C., Jr.
1999-01-01
The effect of stitches on the failure of a single lap joint configuration was determined in a combined experimental and finite element study. The experimental program was conducted to determine debond growth under static monotonic loading. The stitches were shown to delay the initiation of the debond and provide load transfer beyond the load necessary to completely debond the stitched lap joint. The experimentally determined debond length vs. applied load was used as an input parameter in the finite element analysis of both configurations. The strain energy release rates at the debond from were calculated using plate finite elements. Nonlinear fastener elements were used to model the stitches and multipoint constraints were used to model the contact problem. Models of the unstitched configuration showed significant values of modes I and II across the width of the joint and showed that mode III is zero at the centerline but increases near the free edge. Models of the stitched configuration showed that the stitches were effective in reducing mode I to zero, but had less of an effect on modes II and III.
ReadXplorer—visualization and analysis of mapped sequences
Hilker, Rolf; Stadermann, Kai Bernd; Doppmeier, Daniel; Kalinowski, Jörn; Stoye, Jens; Straube, Jasmin; Winnebald, Jörn; Goesmann, Alexander
2014-01-01
Motivation: Fast algorithms and well-arranged visualizations are required for the comprehensive analysis of the ever-growing size of genomic and transcriptomic next-generation sequencing data. Results: ReadXplorer is a software offering straightforward visualization and extensive analysis functions for genomic and transcriptomic DNA sequences mapped on a reference. A unique specialty of ReadXplorer is the quality classification of the read mappings. It is incorporated in all analysis functions and displayed in ReadXplorer's various synchronized data viewers for (i) the reference sequence, its base coverage as (ii) normalizable plot and (iii) histogram, (iv) read alignments and (v) read pairs. ReadXplorer's analysis capability covers RNA secondary structure prediction, single nucleotide polymorphism and deletion–insertion polymorphism detection, genomic feature and general coverage analysis. Especially for RNA-Seq data, it offers differential gene expression analysis, transcription start site and operon detection as well as RPKM value and read count calculations. Furthermore, ReadXplorer can combine or superimpose coverage of different datasets. Availability and implementation: ReadXplorer is available as open-source software at http://www.readxplorer.org along with a detailed manual. Contact: rhilker@mikrobio.med.uni-giessen.de Supplementary information: Supplementary data are available at Bioinformatics online. PMID:24790157
Analysis of Electrowetting Dynamics with Level Set Method
NASA Astrophysics Data System (ADS)
Park, Jun Kwon; Hong, Jiwoo; Kang, Kwan Hyoung
2009-11-01
Electrowetting is a versatile tool to handle tiny droplets and forms a backbone of digital microfluidics. Numerical analysis is necessary to fully understand the dynamics of electrowetting, especially in designing electrowetting-based liquid lenses and reflective displays. We developed a numerical method to analyze the general contact-line problems, incorporating dynamic contact angle models. The method was applied to the analysis of spreading process of a sessile droplet for step input voltages in electrowetting. The result was compared with experimental data and analytical result which is based on the spectral method. It is shown that contact line friction significantly affects the contact line motion and the oscillation amplitude. The pinning process of contact line was well represented by including the hysteresis effect in the contact angle models.
NASA Astrophysics Data System (ADS)
Moosavi, Saeideh Sadat; Norouzbeigi, Reza; Velayi, Elmira
2017-11-01
In the present work, copper oxide superhydrophobic surface is fabricated on a copper foil via the chemical bath deposition (CBD) method. The effects of some influential factors such as initial concentrations of Cu (II) ions and the surface energy modifier, solution pH, reaction and modification steps time on the wettability property of copper oxide surface were evaluated using Taguchi L16 experimental design. Results showed that the initial concentration of Cu (II) has the most significant impact on the water contact angle and wettability characteristics. The XRD, SEM, AFM and FTIR analyses were used to characterize the copper oxide surfaces. The Water contact angle (WCA) and contact angle hysteresis (CAH) were also measured. The SEM results indicated the formation of a flower-like micro/nano dual-scale structure of copper oxide on the substrate. This structure composed of numerous nano-petals with a thickness of about 50 nm. As a result, a copper oxide hierarchical surface with WCA of 168.4°± 3.5° and CAH of 2.73° exhibited the best superhydrophobicity under proposed optimum condition. This result has been obtained just by 10 min hydrolysis reaction. Besides, this surface showed a good stability under acidic and saline conditions.
Sorption kinetics of Zn (II) ion by thermally treated rice husk
NASA Astrophysics Data System (ADS)
Ong, K. K.; Tarmizi, A. F. A.; Wan Yunus W. M., Z.; Safidin, K. M.; Fitrianto, A.; Hussin, A. G. A.; Azmi, F. M.
2015-05-01
Agricultural wastes such as orange peels, tea leave waste, rice husk and corn cobs have been widely studied as sorbents for heavy metal ion removal from various wastewaters. In order to understand their sorption mechanism, the adsorption kinetics is studied. This report describes the kinetics study of a thermally treated rice husk to adsorb Zn (II) ion from an aqueous solution. The adsorbent was obtained by heating the rice husk in a furnace at 500°C for two hours. Increase the contact period improved percentage of the removal of Zn (II) ion until an equilibrium was reached. The data obtained showed that the adsorption of Zn (II) ion by thermally treated rice husk obeyed pseudo-second order kinetics model, which is in agreement with chemisorption as the rate limiting mechanism.
Non-contact FBG sensing based steam turbine rotor dynamic balance vibration detection system
NASA Astrophysics Data System (ADS)
Li, Tianliang; Tan, Yuegang; Cai, Lin
2015-10-01
This paper has proposed a non-contact vibration sensor based on fiber Bragg grating sensing, and applied to detect vibration of steam turbine rotor dynamic balance experimental platform. The principle of the sensor has been introduced, as well as the experimental analysis; performance of non-contact FBG vibration sensor has been analyzed in the experiment; in addition, turbine rotor dynamic vibration detection system based on eddy current displacement sensor and non-contact FBG vibration sensor have built; finally, compared with results of signals under analysis of the time domain and frequency domain. The analysis of experimental data contrast shows that: the vibration signal analysis of non-contact FBG vibration sensor is basically the same as the result of eddy current displacement sensor; it verified that the sensor can be used for non-contact measurement of steam turbine rotor dynamic balance vibration.
Female-partnered and single women's contact motivations and experiences with donor-linked families.
Goldberg, A E; Scheib, J E
2015-06-01
What are female-partnered and single mothers' motivations and experiences at one donor insemination (DI) program with regard to contacting other families who share the same sperm donor? By and large, women reported seeking contact to obtain (i) support for their children and/or themselves, and (ii) information about shared traits and medical problems, ultimately describing a range of contact experiences, both positive (e.g. special bond created) and negative (e.g. uncomfortable encounters). There is a growing phenomenon of donor insemination families-parents and/or offspring-seeking others who share their donor (i.e. are 'donor-linked'). There is limited understanding about parental motivations and experiences-especially in the presence of a second parent-due to the methodological constraints of previous quantitative studies. Semi-structured telephone interviews were conducted with 50 donor insemination mothers (14 single, 36 female-partnered). Participants were recruited by email invitation to parent members of a family-matching service at one donor insemination program in the USA. The criterion for inclusion was having matched to at least one donor-linked family. Among the 50 mothers interviewed, all had at least one child conceived via donor insemination, who was between ages 0 and 15 years at first contact. Families matched with a median of three donor-linked families (range 1-10). Interview data were analyzed through qualitative (i.e. thematic) analysis. Overarching themes emerged of seeking contact to obtain (i) support and (ii) information about children's shared physical and psychological traits. Some wanted to increase their child's family network, through adding a sibling, but more often as extended family. Data, from partnered parents especially, revealed the challenges of balancing the boundaries of family formed without the genetic link with the perceived benefits of exploring the child's donor origins. Interviews focused on openness and information-sharing were conducted with parents from one American donor insemination program. Findings are limited to individuals who were open enough to share their experiences and able to take the time to do so. As donor-linking services become established independently (e.g. donor insemination program registries) or by the government (e.g. Victoria, Australia's Voluntary Register), these findings provide evidence that linking services are valued by individuals affected by donor conception. Caution is warranted, however, in that some participants reported mismatched expectations, both across donor-linked families and within families (e.g. between partners), suggesting the need for information and guidance both during and after matching. Overall, the range and balance of reported positives and negatives indicate that donor-linking can provide individuals with support and donor origins information-which are particularly important when these are not available elsewhere. Clark University provided support. No competing interests. © The Author 2015. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
Chen, Lei; Xiao, Chen; Yu, Bingjun; Kim, Seong H; Qian, Linmao
2017-09-26
In order to understand the interfacial parameters governing the friction force (F t ) between silicon oxide surfaces in humid environment, the sliding speed (v) and relative humidity (RH) dependences of F t were measured for a silica sphere (1 μm radius) sliding on a silicon oxide (SiO x ) surface, using atomic force microscopy (AFM), and analyzed with a mathematical model describing interfacial contacts under a dynamic condition. Generally, F t decreases logarithmically with increasing v to a cutoff value below which its dependence on interfacial chemistry and sliding condition is relatively weak. Above the cutoff value, the logarithmic v dependence could be divided into two regimes: (i) when RH is lower than 50%, F t is a function of both v and RH; (ii) in contrast, at RH ≥ 50%, F t is a function of v only, but not RH. These complicated v and RH dependences were hypothesized to originate from the structure of the water layer adsorbed on the surface and the water meniscus around the annulus of the contact area. This hypothesis was tested by analyzing F t as a function of the water meniscus area (A m ) and volume (V m ) estimated from a thermally activated water-bridge formation model. Surprisingly, it was found that F t varies linearly with V m and correlates poorly with A m at RH < 50%; and then its V m dependence becomes weaker as RH increases above 50%. Comparing the friction data with the attenuated total reflection infrared (ATR-IR) spectroscopy analysis result of the adsorbed water layer, it appeared that the solidlike water layer structure formed on the silica surface plays a critical role in friction at RH < 50% and its contribution diminishes at RH ≥ 50%. These findings give a deeper insight into the role of water condensation in friction of the silicon oxide single asperity contact under ambient conditions.
Charging of multiple interacting particles by contact electrification.
Soh, Siowling; Liu, Helena; Cademartiri, Rebecca; Yoon, Hyo Jae; Whitesides, George M
2014-09-24
Many processes involve the movement of a disordered collection of small particles (e.g., powders, grain, dust, and granular foods). These particles move chaotically, interact randomly among themselves, and gain electrical charge by contact electrification. Understanding the mechanisms of contact electrification of multiple interacting particles has been challenging, in part due to the complex movement and interactions of the particles. To examine the processes contributing to contact electrification at the level of single particles, a system was constructed in which an array of millimeter-sized polymeric beads of different materials were agitated on a dish. The dish was filled almost completely with beads, such that beads did not exchange positions. At the same time, during agitation, there was sufficient space for collisions with neighboring beads. The charge of the beads was measured individually after agitation. Results of systematic variations in the organization and composition of the interacting beads showed that three mechanisms determined the steady-state charge of the beads: (i) contact electrification (charging of beads of different materials), (ii) contact de-electrification (discharging of beads of the same charge polarity to the atmosphere), and (iii) a long-range influence across beads not in contact with one another (occurring, plausibly, by diffusion of charge from a bead with a higher charge to a bead with a lower charge of the same polarity).
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77 FR 33290 - National Organic Program (NOP); Sunset Review (2012)
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2012-06-06
... the SUPPLEMENTARY INFORMATION. FOR FURTHER INFORMATION CONTACT: Melissa R. Bailey, Ph.D., Director, Standards Division, Telephone: (202) 720-3252; Fax: (202) 205-7808. SUPPLEMENTARY INFORMATION: I. Background... sprout production according to EPA label directions. (i) Calcium hypochlorite. (ii) Chlorine dioxide...
Code of Federal Regulations, 2013 CFR
2013-04-01
... well as the following: (1) Non-participatory preferred stock, which is defined as non-convertible...) Any foreign securities exchange or non-exchange market designated by the Commission. Attributes to be... from the registration requirements; (ii) Contact with persons excluded from the definition of “U.S...
Code of Federal Regulations, 2012 CFR
2012-04-01
... well as the following: (1) Non-participatory preferred stock, which is defined as non-convertible...) Any foreign securities exchange or non-exchange market designated by the Commission. Attributes to be... from the registration requirements; (ii) Contact with persons excluded from the definition of “U.S...
21 CFR 870.5900 - Thermal regulating system.
Code of Federal Regulations, 2010 CFR
2010-04-01
... system. (a) Identification. A thermal regulating system is an external system consisting of a device that is placed in contact with the patient and a temperature controller for the device. The system is used to regulate patient temperature. (b) Classification. Class II (performance standards). ...
Contact compliance effects in the frictional response of bioinspired fibrillar adhesives
Piccardo, Marco; Chateauminois, Antoine; Fretigny, Christian; Pugno, Nicola M.; Sitti, Metin
2013-01-01
The shear failure and friction mechanisms of bioinspired adhesives consisting of elastomer arrays of microfibres terminated by mushroom-shaped tips are investigated in contact with a rigid lens. In order to reveal the interplay between the vertical and lateral loading directions, experiments are carried out using a custom friction set-up in which normal stiffness can be made either high or low when compared with the stiffness of the contact between the fibrillar adhesive and the lens. Using in situ contact imaging, the shear failure of the adhesive is found to involve two successive mechanisms: (i) cavitation and peeling at the contact interface between the mushroom-shaped fibre tip endings and the lens; and (ii) side re-adhesion of the fibre's stem to the lens. The extent of these mechanisms and their implications regarding static friction forces is found to depend on the crosstalk between the normal and lateral loading directions that can result in contact instabilities associated with fibre buckling. In addition, the effects of the viscoelastic behaviour of the polyurethane material on the rate dependence of the shear response of the adhesive are accounted for. PMID:23554349
Ichnofabrics and Facies in the Paleocene of Chicxulub: A Record of the Recovery of Life Post-Impact
NASA Astrophysics Data System (ADS)
Whalen, M. T.; O'Malley, K.; Lowery, C. M.; Rodriguez-Tovar, F. J.; Gulick, S. P. S.; Morgan, J. V.
2017-12-01
IODP/ICDP Expedition 364 recovered 829 m of core at Site M0077 including 110 m of post-impact, (hemi)pelagic Paleogene sedimentary rocks overlying the Chicxulub impact crater peak ring formed from suevite, melt rock, and granitic basement. The transition between suevite and Paleocene limestone (Unit 1F) is a remarkable fining upward package of gravel to sand-sized suevite (Unit 2A) overlain by the laminated carbonate-rich Unit 1G that records deposition of fine-grained material post-impact and contains a mix of Late Cretaceous and earliest Danian taxa. This study concentrates on the overlying Unit 1F. The ichnofabric index (ii, 1-6 indicating no bioturbation to complete homogenization), provides a semiquantitative estimate of burrow density to help assess the return of life to the crater. Unit 1F is 10 m thick with a sharp contact at the base of a green claystone (ii 2) that overlies Unit 1G. It consists of cm-dm interbedded blue-gray marlstone (ii 2) grading upward into gray to blue-gray wacke/packstone (ii 3-5). Contacts between facies are mostly gradational due to burrowing. The upper 3 m of the unit is a yellow-brown burrowed packstone (ii 4) intercalated with gray marlstone (ii 2). The uppermost 7.5 cm is calcite cemented with 1 cm wide burrows (ii 3-4) and fine to coarse sand size clasts including foraminifera. The upper surface of the unit is a hardground with an 2 Myr unconformity overlain by Eocene rocks. The first well-defined burrows occur in the upper 30 cm of Unit 1G. Unequivocal burrows (ii 2) that disturb sedimentary facies occur in overlying Unit 1F with values of 3-5 recorded in the overlying 10 cm indicating significant disruption of primary sedimentary structures. The iis in Unit 1F vary between 2 and 5 with rare laminated intervals without bioturbation (ii 1). Values of ii correlate well with facies changes, i.e. marlstones display lower iis than more carbonate-rich facies, implying a depth and/or redox control on burrower distribution. The ii data indicate that burrowers were re-established in the crater before the end of deposition of Unit 1G. The lowest Danian zone Pα is documented in the lowermost part of Unit 1F. Trace makers were thus active by the earliest Danian with an increase in abundance and diversity during the lower Danian, indicating a rapid and continuous return of benthic life to the crater.
Elastohydrodynamic lubrication theory
NASA Technical Reports Server (NTRS)
Hamrock, B. J.; Dowson, D.
1982-01-01
The isothermal elastohydrodynamic lubrication (EHL) of a point contact was analyzed numerically by simultaneously solving the elasticity and Reynolds equations. In the elasticity analysis the contact zone was divided into equal rectangular areas, and it was assumed that a uniform pressure was applied over each area. In the numerical analysis of the Reynolds equation, a phi analysis (where phi is equal to the pressure times the film thickness to the 3/2 power) was used to help the relaxation process. The EHL point contact analysis is applicable for the entire range of elliptical parameters and is valid for any combination of rolling and sliding within the contact.
Pastrav, L C; Devos, J; Van der Perre, G; Jaecques, S V N
2009-05-01
In total hip replacement (THR) a good initial stability of the prosthetic stem in the femur, which corresponds to a good overall initial contact, will help assure a good long-term result. During the insertion the implant stability increases and, as a consequence, the resonance frequencies increase, allowing the assessment of the implant fixation by vibration analysis. The influence of changing contact conditions on the resonance frequencies was however not yet quantitatively understood and therefore a finite element analysis (FEA) was set up. Modal analyses on the hip stem-femur system were performed in various contact situations. By modelling the contact changes by means of the contact tolerance options in the finite element software, contact could be varied over the entire hip stem surface or only in specific zones (proximal, central, distal) while keeping other system parameters constant. The results are in agreement with previous observations: contact increase causes positive resonance frequency shifts and the dynamic behaviour is most influenced by contact changes in the proximal zone. Although the finite element analysis did not establish a monotonous relationship between the vibrational mode number and the magnitude of the resonance frequency shift, in general the higher modes are more sensitive to the contact change.
Prediction of contact path and load sharing in spiral bevel gears
NASA Technical Reports Server (NTRS)
Bibel, George D.; Tiku, Karuna; Kumar, Ashok
1994-01-01
A procedure is presented to perform a contact analysis of spiral bevel gears in order to predict the contact path and the load sharing as the gears roll through mesh. The approach utilizes recent advances in automated contact methods for nonlinear finite element analysis. A sector of the pinion and gear is modeled consisting of three pinion teeth and four gear teeth in mesh. Calculation of the contact force and stresses through the gear meshing cycle are demonstrated. Summary of the results are presented using three dimensional plots and tables. Issues relating to solution convergence and requirements for running large finite element analysis on a supercomputer are discussed.
Yamamoto, Nao; Ejima, Keisuke; Nishiura, Hiroshi
2018-05-31
It is believed that sexually active people, i.e. people having multiple or concurrent sexual partners, are at a high risk of sexually transmitted infections (STI), but they are likely to be more aware of the risk and may exhibit greater fraction of the use of condom. The purpose of the present study is to examine the correlation between condom use and sexual contact pattern and clarify its impact on the transmission dynamics of STIs using a mathematical model. The definition of sexual contact pattern can be broad, but we focus on two specific aspects: (i) type of partnership (i.e. steady or casual partnership) and (ii) existence of concurrency (i.e. with single or multiple partners). Systematic review and meta-analysis of published studies are performed, analysing literature that epidemiologically examined the relationship between condom use and sexual contact pattern. Subsequently, we employ an epidemiological model and compute the reproduction number that accounts for with and without concurrency so that the corresponding coverage of condom use and its correlation with existence of concurrency can be explicitly investigated using the mathematical model. Combining the model with parameters estimated from the meta-analysis along with other assumed parameters, the impact of varying the proportion of population with multiple partners on the reproduction number is examined. Based on systematic review, we show that a greater number of people used condoms during sexual contact with casual partners than with steady partners. Furthermore, people with multiple partners use condoms more frequently than people with a single partner alone. Our mathematical model revealed a positive relationship between the effective reproduction number and the proportion of people with multiple partners. Nevertheless, the association was reversed to be negative by employing a slightly greater value of the relative risk of condom use for people with multiple partners than that empirically estimated. Depending on the correlation between condom use and the existence of concurrency, association between the proportion of people with multiple partners and the reproduction number can be reversed, suggesting the sexually active population is not necessary a primary target population to encourage condom use (i.e., sexually less active individuals could equivalently be a target in some cases).
Guidance of Axons by Local Coupling of Retrograde Flow to Point Contact Adhesions.
Nichol, Robert H; Hagen, Kate M; Lumbard, Derek C; Dent, Erik W; Gómez, Timothy M
2016-02-17
Growth cones interact with the extracellular matrix (ECM) through integrin receptors at adhesion sites termed point contacts. Point contact adhesions link ECM proteins to the actin cytoskeleton through numerous adaptor and signaling proteins. One presumed function of growth cone point contacts is to restrain or "clutch" myosin-II-based filamentous actin (F-actin) retrograde flow (RF) to promote leading edge membrane protrusion. In motile non-neuronal cells, myosin-II binds and exerts force upon actin filaments at the leading edge, where clutching forces occur. However, in growth cones, it is unclear whether similar F-actin-clutching forces affect axon outgrowth and guidance. Here, we show in Xenopus spinal neurons that RF is reduced in rapidly migrating growth cones on laminin (LN) compared with non-integrin-binding poly-d-lysine (PDL). Moreover, acute stimulation with LN accelerates axon outgrowth over a time course that correlates with point contact formation and reduced RF. These results suggest that RF is restricted by the assembly of point contacts, which we show occurs locally by two-channel imaging of RF and paxillin. Further, using micropatterns of PDL and LN, we demonstrate that individual growth cones have differential RF rates while interacting with two distinct substrata. Opposing effects on RF rates were also observed in growth cones treated with chemoattractive and chemorepulsive axon guidance cues that influence point contact adhesions. Finally, we show that RF is significantly attenuated in vivo, suggesting that it is restrained by molecular clutching forces within the spinal cord. Together, our results suggest that local clutching of RF can control axon guidance on ECM proteins downstream of axon guidance cues. Here, we correlate point contact adhesions directly with clutching of filamentous actin retrograde flow (RF), which our findings strongly suggest guides developing axons. Acute assembly of new point contact adhesions is temporally and spatially linked to attenuation of RF at sites of forward membrane protrusion. Importantly, clutching of RF is modulated by extracellular matrix (ECM) proteins and soluble axon guidance cues, suggesting that it may regulate axon guidance in vivo. Consistent with this notion, we found that RF rates of spinal neuron growth cones were slower in vivo than what was observed in vitro. Together, our study provides the best evidence that growth cone-ECM adhesions clutch RF locally to guide axons in vivo. Copyright © 2016 the authors 0270-6474/16/362267-16$15.00/0.
Rodrigues, Ana Catarina; Belas, Adriana; Marques, Cátia; Cruz, Luís; Gama, Luís T; Pomba, Constança
2018-05-01
Methicillin-resistant staphylococci (MRS), namely Staphylococcus aureus (MRSA) and Staphylococcus pseudintermedius (MRSP), are opportunistic agents of great importance in human and veterinary medicine. The aims of this study were to investigate the frequency, persistence, and risk factors associated with nasal colonization by MRS in people in daily contact with animals in Portugal. Seventy-nine out of 129 (61.2%) participants were found to be colonized by, at least, one methicillin-resistant (MR) staphylococci species (MR Staphylococcus epidermidis [n = 68], MRSA [n = 19], MR Staphylococcus haemolyticus [n = 7], MRSP [n = 2], and other coagulase-negative staphylococci [n = 4]). Three lineages were identified among the MRSA isolates (n = 7): the major human healthcare clone in Portugal (ST22-t032-IV, n = 3), the livestock-associated MRSA (ST398-t108-V, n = 3), and the New York-/Japan-related clone (ST105-t002-II, n = 1). MRSP isolates belonged to the European clone ST71-II-III. We identified two risk factors for nasal colonization by MRS in healthy humans: (i) being a veterinary professional (veterinarian and veterinary nurse) (p < 0.0001, odds ratio [OR] = 6.369, 95% confidence interval [CI, 2.683-15.122]) and (ii) have contacted with one MRSA- or MRSP-positive animal (p = 0.0361, OR = 2.742, 95% CI [1.067-7.045]). The follow-up study revealed that the majority (85%) remain colonized. This study shows that MRS in veterinary clinical practice is a professional hazard and highlights the need to implement preventive measures to minimize spread.
Eisen, Lars; Rose, Dominic; Prose, Robert; Breuner, Nicole E; Dolan, Marc C; Thompson, Karen; Connally, Neeta
2017-10-01
Summer-weight clothing articles impregnated with permethrin are available as a personal protective measure against human-biting ticks in the United States. However, very few studies have addressed the impact of contact with summer-weight permethrin-treated textiles on tick vigor and behavior. Our aim was to generate new knowledge of how permethrin-treated textiles impact nymphal Ixodes scapularis ticks, the primary vectors in the eastern United States of the causative agents of Lyme disease, human anaplasmosis, and human babesiosis. We developed a series of bioassays designed to: (i) clarify whether permethrin-treated textiles impact ticks through non-contact spatial repellency or contact irritancy; (ii) evaluate the ability of ticks to remain in contact with vertically oriented permethrin-treated textiles, mimicking contact with treated clothing on arms or legs; and (iii) determine the impact of timed exposure to permethrin-treated textiles on the ability of ticks to move and orient toward a human finger stimulus, thus demonstrating normal behavior. Our results indicate that permethrin-treated textiles provide minimal non-contact spatial repellency but strong contact irritancy against ticks, manifesting as a "hot-foot" effect and resulting in ticks actively dislodging from contact with vertically oriented treated textile. Preliminary data suggest that the contact irritancy hot-foot response may be weaker for field-collected nymphs as compared with laboratory-reared nymphs placed upon permethrin-treated textile. We also demonstrate that contact with permethrin-treated textiles negatively impacts the vigor and behavior of nymphal ticks for >24h, with outcomes ranging from complete lack of movement to impaired movement and unwillingness of ticks displaying normal movement to ascend onto a human finger. The protective effect of summer-weight permethrin-treated clothing against tick bites merits further study. Published by Elsevier GmbH.
The Mathematical and Computer Aided Analysis of the Contact Stress of the Surface With 4th Order
NASA Astrophysics Data System (ADS)
Huran, Liu
Inspired from some gears with heavy power transmission in practical usage after serious plastic deformation in metallurgical industry, we believe that there must existed some kind of gear profile which is most suitable in both the contact and bending fatigue strength. From careful analysis and deep going investigation, we think that it is the profile of equal conjugate curvature with high order of contact, and analyzed the forming principle of this kind of profile. Based on the second curve and comparative analysis of fourth order curves, combined with Chebyshev polynomial terms of higher order contact with tooth contact stress formula derived. Note high exposure in the case of two extreme points of stress and extreme positions and the derived extreme contact stress formula. Finally, a pair of conjugate gear tooth profile curvature provides specific contact stress calculation.
Toward patient-specific articular contact mechanics
Ateshian, Gerard A.; Henak, Corinne R.; Weiss, Jeffrey A.
2015-01-01
The mechanics of contacting cartilage layers is fundamentally important to understanding the development, homeostasis and pathology of diarthrodial joints. Because of the highly nonlinear nature of both the materials and the contact problem itself, numerical methods such as the finite element method are typically incorporated to obtain solutions. Over the course of five decades, we have moved from an initial qualitative understanding of articular cartilage material behavior to the ability to perform complex, three-dimensional contact analysis, including multiphasic material representations. This history includes the development of analytical and computational contact analysis methods that now provide the ability to perform highly nonlinear analyses. Numerical implementations of contact analysis based on the finite element method are rapidly advancing and will soon enable patient-specific analysis of joint contact mechanics using models based on medical image data. In addition to contact stress on the articular surfaces, these techniques can predict variations in strain and strain through the cartilage layers, providing the basis to predict damage and failure. This opens up exciting areas for future research and application to patient-specific diagnosis and treatment planning applied to a variety of pathologies that affect joint function and cartilage homeostasis. PMID:25698236
Interaction of Mycobacterium avium-containing phagosomes with the antigen presentation pathway.
Ullrich, H J; Beatty, W L; Russell, D G
2000-12-01
Pathogenic mycobacteria infect macrophages where they replicate in phagosomes that minimize contact with late endosomal/lysosomal compartments. Loading of Ags to MHC class II molecules occurs in specialized compartments with late endosomal characteristics. This points to a sequestration of mycobacteria-containing phagosomes from the sites where Ags meet MHC class II molecules. Indeed, in resting macrophages MHC class II levels decreased strongly in phagosomes containing M. avium during a 4-day infection. Phagosomal MHC class II of early (4 h) infections was partly surface-derived and associated with peptide. Activation of host macrophages led to the appearance of H2-M, a chaperon of Ag loading, and to a strong increase in MHC class II molecules in phagosomes of acute (1 day) infections. Comparison with the kinetics of MHC class II acquisition by IgG-coated bead-containing phagosomes suggests that the arrest in phagosome maturation by mycobacteria limits the intersection of mycobacteria-containing phagosomes with the intracellular trafficking pathways of Ag-presenting molecules.
Arribas, Oscar J; Galán, Pedro; Remón, Núria; Naveira, Horacio
2014-05-19
Iberolacerta populations from the Northern Montes de Leon (NML) were studied by means of external morphology (scalation and biometry), osteology and genetics (mtDNA and microsatellites), searching for their homogeneity ("intrazonalanalysis") and, once verified, comparing them with Iberolacerta monticola s. str. (from Central Cantabrian Mountains)and/. gal ani (from Southern Montes de Leon) ("extrazonal analysis") from neighboring areas.Our "intrazonal analysis" revealed discordances between the different approaches, especially the patterns of variation of nuclear microsatellites (congruent with external morphology) and mtDNA, namely a very low nuclear differentiation between relatively highly differentiated mtDNA lineages. The morphological approach was unable to discriminate any of the populations as significantly different from the others in the NML. Mitochondrial DNA revealed a haplotype lineage closely related to I. galani (MNL-II in our text) in some specimens of Sierra de Villabandfn and Suspiron, but these populations are morphologically indistinguishable from the main part of the other populations that belong to lineage NML-1,phylogenetically closer to/. monticola. After a separation from I. manti cola ca. 1.8 Mya, the populations in this geographic region must have suffered at least two different waves of gene flow from I. gal ani, the second one not much later than 0.5 Mya. Microsatellite results indicate that all the NML populations are genetically similar in terms of their nuclear genomes,independently of their mitochondrial differentiation (NML-I vs. NML-II haplotype groups). Since all the morphological and microsatellite evidences point towards the fact that, independently of the mitochondrial haplotypes that they bear (NML-1 or NML-II), there is only one taxon in the area, we describe it as: Iberolacerta monticola astur ssp. nov.Concerning the relationships of I. m. astur ssp. nov. with I. monticola s. str. and I. gal ani ("extra zonal analysis"), in the female analyses the new taxon centroid is closer to I. monticola s. str. than to I. gal ani (more similarity with I manticolas.str.), whereas in the male analyses the relationship is just the contrary (closer to I. gal ani, paralleling the direction of the hypothesized past hybridization). Moreover, in both sexes' ANOVA, I. m. astur ssp. nov. results more similar (lessP<0.05 differences) to I. galani than to I. monticola s. str. Osteologically, I. m. astur ssp. nov. is slightly more similar toI. monticola s. str. than to I. galani, especially in the squamosal bone, which is regularly arched (primitive shape). Genetically,as indicated above, the NML populations can be subdivided in two groups according to their mitochondrial DNA,namely NML-I (bearing clearly differentiated haplotypes, phylogenetically closer to I. monticola) and NML-II (whose haplotypes could have been mistaken for those of an I. gal ani population). This mitochondrial subdivision has at most a subtle nuclear correlate, however. According to the nuclear microsatellite markers, all the NML populations belong to a single group(/. m. astur ssp. nov.), which would be more similar to I. gal ani than to I monticola, with NML-II populations lying closer to I. galani than those from the NML-I group and, correspondingly, more distant from I. monticola. The discordant phylogenetic signal of mitochondrial and nuclear markers is discussed in terms of past introgression events and sex-biases in phylopatry and dispersion in these species. Iberolacerta manti cola astur ssp. nov., inhabits the Northern Montes de Leon (Sierra de Gistreo sensu latissimo ): Gistredo,Catoute, Tambaron, Nevadfn, Villabandfn (or Macizo del Alto de Ia Canada), Arcos del Agua (or Fernan Perez),Tiendas and Suspiron, mainly in quartzite and slate rock substrates. Its current distribution, cornered in the NW of theNorthern part of the Montes de Leon, suggests a possible competitive exclusion between this taxon and/. galani, as the galani haplotypes (NML-II) appear cornered in the most harsh and continental areas, speaking also about a, even in the past, very limited presence of this species in the area that probably was soon absorbed by I. m. astur ssp. nov. (with NMLI haplotypes). Variation in watershed limits (especially with l montico/a s. str. in the North) and Pleistocene climatic oscillations(with I. gal ani in the South) probably played a crucial role in isolation of the different Iberolacerta colonizationwaves in this zone. These changes in the boundaries among watersheds limited the contact between the NML and the main Cantabrian Mountains, restricting to narrow points (different along time) the contact between the two ranges, and thus,the areas for possible contact between I. m. astur ssp. nov. and I. monticola s. str. (see Fig. lB). The origin of this tax on dates back to the end of Pliocene or Lower Pleistocene (around 1.8 Mya), according to mtDNA divergence. On the other side, climatic oscillations allowed expansion and contact with the more continental harsh climate-dwelling I. gal ani.
Jacob, Mathias; Brinkmann, Jürgen; Schmidt, Thomas J
2012-05-01
Two preparations are currently in use for the diagnosis of allergic contact dermatitis caused by Asteraceae: (i) Sesquiterpene lactone (SL) mix [three pure sesquiterpene lactones (STLs)], whose use has been questioned, owing to an insufficient rate of true-positive results; and (ii) Compositae mix, consisting of five Asteraceae extracts, which is problematic because of lack of standardization and questionable reproducibility. To analyse the reasons for the narrow sensitivity of SL mix from a chemoinformatic point of view, and to propose a solution by rational selection of alternative constituents for a new SL mix II covering a broader cohort of allergic patients. Structural and biological information on allergenic STLs was retrieved from databases and the literature, and molecular modelling and chemoinformatic computations were performed. An explanation for the insufficient hit rate of SL mix is that the three constituents possess extremely similar molecular structures/properties and do not represent well the structural diversity of allergenic STLs. STLs that are known as constituents of Compositae mix plants show much a wider diversity, which explains the higher positive rate. On the basis of their positions in chemical property space, a new collection of STLs that more evenly cover the overall structural diversity spectrum is proposed. SL mix II is likely to detect a larger number of patients sensitized to Asteraceae. © 2012 John Wiley & Sons A/S.
A study of the Au/Ni ohmic contact on p-GaN
DOE Office of Scientific and Technical Information (OSTI.GOV)
Qiao, D.; Yu, L. S.; Lau, S. S.
2000-10-01
The formation mechanism of the ohmic Au/Ni/p-GaN contact has been investigated. We found that it is essential to (i) deposit a structure of Au and Ni in the proper deposition sequence, and (ii) anneal the bilayer structure in an oxygen containing ambient. Our findings indicated that oxygen assists the layer-reversal reactions of the metallized layers to form a structure of NiO/Au/p-GaN. The presence of oxygen during annealing appears to increase the conductivity of the p-GaN. It is further suggested that Ni removes or reduces the surface contamination of the GaN sample before or during layer reversal. In the final contactmore » structure, an Au layer, which has a large work function, is in contact with the p-GaN substrate. The presence of Au in the entire contacting layer improves the conductivity of the contact. An ohmic formation mechanism based on our experimental results is proposed and discussed in this work. (c) 2000 American Institute of Physics.« less
Modification of hydroxyapatite with ion-selective complexants: 1-hydroxyethane-1,1-diphosphonic acid
DOE Office of Scientific and Technical Information (OSTI.GOV)
Daniels, Yasmine; Lyczko, Nathalie; Nzihou, Ange
Hydroxyapatite (HAP) was modified with 1-hydroxyethane-1,1-diphosphonic acid (HEDP), and its effect on divalent metal ion binding was determined. HAP was synthesized from calcium hydroxide and phosphoric acid. After calcination, it was modified with HEDP, and the influence of time and temperature on the modification was investigated. HEDP incorporation increased as its initial solution concentration increased from 0.01 to 0.50 M. Unmodified and modified HAP were characterized using Fourier transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy, energy dispersive X-ray spectroscopy, and specific surface area analysis. Ca/P ratios, acid capacities, and phosphorus elemental analyses gave the effect of modification on compositionmore » and surface characteristics. A high reaction temperature produced new phosphonate bands at 993, 1082, and 1144 cm –1 that indicated the presence of HEDP. HAP modification at a high temperature–long reaction time had the highest HEDP loading and gave the sharpest XRD peaks. The emergence of new HAP–HEDP strands was observed in SEM images for treated samples while EDS showed high phosphorus contents in these strands. Modified HAP had a high acid capacity from the additional P–OH groups in HEDP. The P(O)OH groups maintain their ability to bind metal ions within the HAP matrix: contacting the modified HAP with 10–4 N nitrate solutions of five transition metal ions gives an affinity sequence of Pb(II) > Cd(II) > Zn(II) > Ni(II) > Cu(II). Here, this result is comparable to that of commercially available di(2-ethylhexyl)phosphoric acid, a common solvent extractant, and the trend is consistent with the Misono softness parameter of metal ion polarizabilities.« less
Arshadi, M; Soleymanzadeh, M; Salvacion, J W L; SalimiVahid, F
2014-07-15
In this study, the synthesis and characterization of a new adsorbent containing nanoscale zerovalent iron particles (NZVI) decorated sineguelas waste (S-NaOH-NZVI) from agriculture biomass was investigated for the adsorption/reduction of inorganic pollution such as Pb(II) ions. The combination of ZVI particles on the surface of sineguelas waste can help to overcome the disadvantage of ultra-fine powders which may have strong tendency to agglomerate into larger particles, resulting in an adverse effect on both effective surface area and catalyst performance. The synthesized materials were characterized with different methods such as FT-IR, BET, XRD, TEM and pHPZC. Good dispersion of NZVI particles (ca. 10-70nm) on the sineguelas waste was observed. The effects of various parameters, such as contact time, pH, concentration, adsorbent dosage and temperature were studied. The adsorption of Pb(II) ions has been studied in terms of pseudo-first- and second-order kinetics, and the Freundlich, Langmuir and Langmuir-Freundlich isotherms models have also been used to the equilibrium adsorption data. The adsorption kinetics followed the mechanism of the pseudo-second-order equation. The thermodynamic parameters (ΔG, ΔH and ΔS) indicated that the adsorption of Pb(II) ions were feasible, spontaneous and endothermic at 25-80°C. XRD analysis indicated the presence of Pb(0) on the S-NaOH-NZVI surface. This study suggests that the modified sineguelas waste by NZVI particles can be prepared at low cost and the materials are environmentally benign for the removal of Pb(II) ions, and likely many other heavy metal ions, from water. Copyright © 2014 Elsevier Inc. All rights reserved.
Modification of hydroxyapatite with ion-selective complexants: 1-hydroxyethane-1,1-diphosphonic acid
Daniels, Yasmine; Lyczko, Nathalie; Nzihou, Ange; ...
2014-12-29
Hydroxyapatite (HAP) was modified with 1-hydroxyethane-1,1-diphosphonic acid (HEDP), and its effect on divalent metal ion binding was determined. HAP was synthesized from calcium hydroxide and phosphoric acid. After calcination, it was modified with HEDP, and the influence of time and temperature on the modification was investigated. HEDP incorporation increased as its initial solution concentration increased from 0.01 to 0.50 M. Unmodified and modified HAP were characterized using Fourier transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy, energy dispersive X-ray spectroscopy, and specific surface area analysis. Ca/P ratios, acid capacities, and phosphorus elemental analyses gave the effect of modification on compositionmore » and surface characteristics. A high reaction temperature produced new phosphonate bands at 993, 1082, and 1144 cm –1 that indicated the presence of HEDP. HAP modification at a high temperature–long reaction time had the highest HEDP loading and gave the sharpest XRD peaks. The emergence of new HAP–HEDP strands was observed in SEM images for treated samples while EDS showed high phosphorus contents in these strands. Modified HAP had a high acid capacity from the additional P–OH groups in HEDP. The P(O)OH groups maintain their ability to bind metal ions within the HAP matrix: contacting the modified HAP with 10–4 N nitrate solutions of five transition metal ions gives an affinity sequence of Pb(II) > Cd(II) > Zn(II) > Ni(II) > Cu(II). Here, this result is comparable to that of commercially available di(2-ethylhexyl)phosphoric acid, a common solvent extractant, and the trend is consistent with the Misono softness parameter of metal ion polarizabilities.« less
Efficiency of soft tissue incision with a novel 445-nm semiconductor laser.
Braun, Andreas; Kettner, Moritz; Berthold, Michael; Wenzler, Johannes-Simon; Heymann, Paul Günther Baptist; Frankenberger, Roland
2018-01-01
Using a 445-nm semiconductor laser for tissue incision, an effective cut is expected due to the special absorption properties of blue laser light in soft tissues. The aim of the present study was the histological evaluation of tissue samples after incision with a 445-nm diode laser. Forty soft tissue specimens were obtained from pork oral mucosa and mounted on a motorized linear translation stage. The handpiece of a high-frequency surgery device, a 970-nm semiconductor laser, and a 445-nm semiconductor laser were connected to the slide, allowing a constant linear movement (2 mm/s) and the same distance of the working tip to the soft tissue's surface. Four incisions were made each: (I) 970-nm laser with conditioned fiber tip, contact mode at 3-W cw; (II-III): 445-nm laser with non-conditioned fiber tip, contact mode at 2-W cw, and non-contact mode (1 mm) at 2 W; and (IV): high-frequency surgery device with straight working tip, 90° angulation, contact mode at 50 W. Histological analysis was performed after H&E staining of the embedded specimens at 35-fold magnification. The comparison of the incision depths showed a significant difference depending on the laser wavelength and the selected laser parameters. The highest incision depth was achieved with the 445-nm laser contact mode (median depth 0.61 mm, min 0.26, max 1.17, interquartile range 0.58) (p < 0.05) with the lowest amount of soft tissue denaturation (p < 0.05). The lowest incision depth was measured for the high-frequency surgical device (median depth 0.36 mm, min 0.12, max 1.12, interquartile range 0.23) (p < 0.05). Using a 445-nm semiconductor laser, a higher cutting efficiency can be expected when compared with a 970-nm diode laser and high-frequency surgery. Even the 445-nm laser application in non-contact mode shows clinically acceptable incision depths without signs of extensive soft tissue denaturation.
Weber, Christian D; Horst, Klemens; Nguyen, Anthony R; Lefering, Rolf; Pape, Hans-Christoph; Hildebrand, Frank
2018-04-19
The participation in extreme and contact sports has grown internationally, despite the significant risk for major and multiple injuries. We conducted this multicenter study to evaluate sport-specific injury patterns and mechanisms, to characterize individuals at risk and to identify possible approaches for prevention. We compared demographic data, severity and patterns of injuries; and the pre- and in-hospital management from an international population-based prospective trauma database (TraumaRegister DGU®). The registry was screened for sport-related injuries, and only patients with major injuries [Injury Severity Score (ISS) ≥ 9 points] related to extreme or contact sports activities were included (January 1, 2002, to December 31, 2012). Parameters were compared for different types of sports activities: (1) Airborne sports, (2) Climbing, (3) Skateboarding/Skating, (4) Contact sports. The following countries participated: Germany, Austria, Switzerland, Finland, Slovenia, Belgium, Luxembourg, and The Netherlands. Statistical analyses were performed with SPSS (Version 22, IBM Inc., Armonk, New York). A total of 278 athletes were identified within the study period and classified into four groups: Airborne sports (n = 105) were associated with the highest injury severity (ISS 22.4 ± 14.6), followed by climbing (n = 35, ISS 16.5 ± 12), skating (n = 67, ISS 15.2 ± 10.3) and contact sports (n = 71, ISS 10.4 ± 9.2). Especially high falls resulted in a significant rate of spinal injuries in airborne activities (68.6%, p < 0.001) and in climbing accidents (45.7%). Skating was associated with the highest rate of loss of consciousness (LOC) at scene (27.1%), the highest pre-hospital intubation rate (33.3%), and also the highest in-hospital mortality (15.2%, p < 0.001), related to major head injuries. Extreme and contact sports related major injuries predominantly affect young male athletes. Especially skaters are at risk for debilitating and lethal head injuries. Individuals recognizing sport-specific hazards might modify their risk behavior. Descriptive Epidemiologic Study, Level II.
TRUPACT-II 157 Examination Report
DOE Office of Scientific and Technical Information (OSTI.GOV)
Barry H. O'Brien; Jeffrey M. Lacy; Kip E. Archibald
2003-12-01
This report presents the results of examination and recovery activities performed on the TRUPACT-II 157 shipping container. The container was part of a contact-handled transuranic waste shipment being transported on a truck to the Waste Isolation Pilot Plant in New Mexico when an accident occurred. Although the transport vehicle sustained only minor damage, airborne transuranic contamination was detected in air samples extracted from inside TRUPACT-II 157 at the Waste Isolation Pilot Plant. Consequently, the shipping container was rejected, resealed, and returned to the Idaho National Engineering and Environmental Laboratory where the payload was disassembled, examined, and recovered for subsequent reshipmentmore » to the Waste Isolation Pilot Plant. This report documents the results of those activities.« less
Design and Stress Analysis of Low-Noise Adjusted Bearing Contact Spiral Bevel Gears
NASA Technical Reports Server (NTRS)
Fuentes, A.; Litvin, F. L.; Mullins, B. R.; Woods, R.; Handschuh, R. F.; Lewicki, David G.
2002-01-01
An integrated computerized approach for design and stress analysis of low-noise spiral bevel gear drives with adjusted bearing contact is proposed. The procedure of computations is an iterative process that requires four separate procedures and provide: (a) a parabolic function of transmission errors that is able to reduce the effect of errors of alignment on noise and vibration, and (b) reduction of the shift of bearing contact caused by misalignment. Application of finite element analysis enables us to determine the contact and bending stresses and investigate the formation of the bearing contact. The design of finite element models and boundary conditions is automated and does not require intermediate CAD computer programs for application of general purpose computer program for finite element analysis.
Laurence, James; Schmid, Katharina; Hewstone, Miles
2018-01-01
This study advances the current literature investigating the relationship between contextual out-group exposure, inter-group attitudes and the role of inter-group contact. Firstly, it introduces the concept of contact-valence into this relationship; that is, whether contact is experienced positively or negatively. Secondly, it presents a comparative analysis of how processes of out-group exposure and frequency of (valenced) contact affect prejudice across both neighbourhoods and workplaces. Applying path analysis modelling to a nationally-representative sample of white British individuals in England, we demonstrate, across both contexts, that increasing out-group exposure is associated with higher rates of both positively- and negatively-valenced contact. This results in exposure exhibiting both positive and negative indirect associations with prejudice via more frequent inter-group mixing. These countervailing contact-pathways help explain how out-group exposure is associated with inter-group attitudes. In neighbourhoods, increasing numbers of individuals experiencing positive-contact suppress an otherwise negative effect of neighbourhood diversity (driven partly by increasing numbers of individuals reporting negative contact). Across workplaces the effect differs such that increasing numbers of individuals experiencing negative-contact suppress an otherwise positive effect of workplace diversity (driven largely by increasing numbers of individuals experiencing positive contact).
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76 FR 49975 - Inspection of Towing Vessels
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21 CFR 884.6160 - Assisted reproduction labware.
Code of Federal Regulations, 2011 CFR
2011-04-01
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21 CFR 884.6160 - Assisted reproduction labware.
Code of Federal Regulations, 2012 CFR
2012-04-01
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21 CFR 884.6160 - Assisted reproduction labware.
Code of Federal Regulations, 2014 CFR
2014-04-01
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21 CFR 884.6160 - Assisted reproduction labware.
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2013-04-01
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75 FR 78966 - Del Norte Resource Advisory Committee (RAC)
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49 CFR 1562.3 - Operating requirements.
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2014-10-01
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Code of Federal Regulations, 2012 CFR
2012-10-01
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Essential Oils, Part I: Introduction.
de Groot, Anton C; Schmidt, Erich
2016-01-01
Essential oils are widely used in the flavor, food, fragrance, and cosmetic industries in many applications. Contact allergy to them is well known and has been described for 80 essential oils. The relevance of positive patch test reactions often remains unknown. Knowledge of the chemical composition of essential oils among dermatologists is suspected to be limited, as such data are published in journals not read by the dermatological community. Therefore, the authors have fully reviewed and published the literature on contact allergy to and chemical composition of essential oils. Selected topics from this publication will be presented in abbreviated form in Dermatitis starting with this issue, including I. Introduction; II. General aspects; III. Chemistry; IV. General aspects of contact allergy; V. Peppermint oil, lavender oil and lemongrass oil; VI: Sandalwood oil, ylang-ylang oil, and jasmine absolute.
Precision of spiral-bevel gears
NASA Technical Reports Server (NTRS)
Litvin, F. L.; Goldrich, R. N.; Coy, J. J.; Zaretsky, E. V.
1982-01-01
The kinematic errors in spiral bevel gear trains caused by the generation of nonconjugate surfaces, by axial displacements of the gears during assembly, and by eccentricity of the assembled gears were determined. One mathematical model corresponds to the motion of the contact ellipse across the tooth surface, (geometry I) and the other along the tooth surface (geometry II). The following results were obtained: (1) kinematic errors induced by errors of manufacture may be minimized by applying special machine settings, the original error may be reduced by order of magnitude, the procedure is most effective for geometry 2 gears, (2) when trying to adjust the bearing contact pattern between the gear teeth for geometry 1 gears, it is more desirable to shim the gear axially; for geometry II gears, shim the pinion axially; (3) the kinematic accuracy of spiral bevel drives are most sensitive to eccentricities of the gear and less sensitive to eccentricities of the pinion. The precision of mounting accuracy and manufacture are most crucial for the gear, and less so for the pinion.
Heidari, Aghdas; Younesi, Habibollah; Mehraban, Zahra; Heikkinen, Harri
2013-10-01
Chitosan-MAA nanoparticles (CS-MAA) with an average size of 10-70 nm were prepared by polymerizing chitosan with methacrylic acid in aqueous solution. The physicochemical properties of nanoparticles were investigated using Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), dynamic light scattering (DLS) and nuclear magnetic resonance (NMR). The adsorption of Pb(II), Cd(II) and Ni(II) from aqueous solution on CS-MAA was studied in a batch system. The effects of the solution pH, initial metal concentration, contact time, and dosage of the adsorbent on the adsorption process were examined. The experimental data were analyzed using the pseudo-second-order kinetic equations and the Langmuir, Freundlich and Redlish-Peterson isotherms. The maximum adsorption capacity was 11.30, 1.84, and 0.87 mg/g for Pb(II), Cd(II) and Ni(II) ions, respectively, obtained by the Langmuir isotherm. However, the adsorption isotherm was better explained by the Freundlich rather than by the Langmuir model, as the high correlation coefficients (R(2)>0.99) were obtained at a higher confidence level. Copyright © 2013 Elsevier B.V. All rights reserved.
NASA Astrophysics Data System (ADS)
Bayar, I.; Khedhiri, L.; Soudani, S.; Lefebvre, F.; Pereira da Silva, P. S.; Ben Nasr, C.
2018-06-01
Two new organic-inorganic hybrid materials, 4-methoxybenzylammonium nitrate, (C8H12NO)·[NO3] (I), and 2-(1-piperazinyl)pyrimidinium bis(perchlorate), (C8H14N4)·[ClO4]2(II), have been synthesized by an acid/base reaction at room temperature, their structures were determined by single crystal X-ray diffraction. Compound (I) crystallizes in the orthorhombic system and Pnma space group with a = 15.7908 (7), b = 6.8032 (3), c = 8.7091 (4) Å, V = 935.60 (7) Å3 with Z = 4. Full-matrix least-squares refinement converged at R = 0.038 and wR(F2) = 0.115. Compound (II) belongs to the monoclinic system, space group P21/c with the following parameters: a = 10.798(2), b = 7.330(1), c = 21.186(2) Å, β = 120.641 (4)°, V = 1442.7 (3) Å3and Z = 4. The structure was refined to R = 0.044, wR(F2) = 0.132. In the structures of (I) and (II), the anionic and cationic entities are interconnected by hydrogen bonding contacts forming three-dimensional networks. Intermolecular interactions were investigated by Hirshfeld surfaces and the contacts of the four different chloride atoms in (II) were compared. The Molecular Electrostatic Potential (MEP) maps and the HOMO and LUMO energy gaps of both compounds were computed. The vibrational absorption bands were identified by infrared spectroscopy. These compounds were also investigated by solid-state 13C, 35Cl and 15N NMR spectroscopy. DFT calculations allowed the attribution of the IR and NMR bands.
Modeling the human body/seat system in a vibration environment.
Rosen, Jacob; Arcan, Mircea
2003-04-01
The vibration environment is a common man-made artificial surrounding with which humans have a limited tolerance to cope due to their body dynamics. This research studied the dynamic characteristics of a seated human body/seat system in a vibration environment. The main result is a multi degrees of freedom lumped parameter model that synthesizes two basic dynamics: (i) global human dynamics, the apparent mass phenomenon, including a systematic set of the model parameters for simulating various conditions like body posture, backrest, footrest, muscle tension, and vibration directions, and (ii) the local human dynamics, represented by the human pelvis/vibrating seat contact, using a cushioning interface. The model and its selected parameters successfully described the main effects of the apparent mass phenomenon compared to experimental data documented in the literature. The model provided an analytical tool for human body dynamics research. It also enabled a primary tool for seat and cushioning design. The model was further used to develop design guidelines for a composite cushion using the principle of quasi-uniform body/seat contact force distribution. In terms of evenly distributing the contact forces, the best result for the different materials and cushion geometries simulated in the current study was achieved using a two layer shaped geometry cushion built from three materials. Combining the geometry and the mechanical characteristics of a structure under large deformation into a lumped parameter model enables successful analysis of the human/seat interface system and provides practical results for body protection in dynamic environment.
Current transient spectroscopy for trapping analysis on Au-free AlGaN/GaN Schottky barrier diode
NASA Astrophysics Data System (ADS)
Hu, J.; Stoffels, S.; Lenci, S.; Bakeroot, B.; Venegas, R.; Groeseneken, G.; Decoutere, S.
2015-02-01
This paper presents a combined technique of high voltage off-state stress and current transient measurements to investigate the trapping/de-trapping characteristics of Au-free AlGaN/GaN Schottky barrier diodes. The device features a symmetric three-terminal structure with a central anode contact surrounded by two separate cathodes. Under the diode off-state stress conditions, the two separate cathodes were electrically shorted. The de-trapping dynamics was studied by monitoring the recovery of the two-dimensional electron gas (2DEG) current at different temperatures by applying 0.5 V at cathode 2 while grounding cathode 1. During the recovery, the anode contact acts as a sensor of changes in diode leakage current. This leakage variation was found to be mainly due to the barrier height variation. With this method, the energy level and capture cross section of different traps in the AlGaN/GaN Schottky barrier diode can be extracted. Furthermore, the physical location of different trapping phenomena is indicated by studying the variation of the diode leakage current during the recovery. We have identified two distinct trapping mechanisms: (i) electron trapping at the AlGaN surface in the vicinity of the Schottky contact which results in the leakage reduction (barrier height ϕB increase) together with RON degradation; (ii) the electron trapping in the GaN channel layer which partially depletes the 2DEG. The physical origin of the two different traps is discussed in the text.
Full 3D opto-electronic simulation tool for nanotextured solar cells (Conference Presentation)
NASA Astrophysics Data System (ADS)
Michallon, Jérôme; Collin, Stéphane
2017-04-01
Increasing efforts on the photovoltaics research have recently been devoted to material savings, leading to the emergence of new designs based on nanotextured and nanowire-based solar cells. The use of small absorber volumes, light-trapping nanostructures and unconventional carrier collection schemes (radial nanowire junctions, point contacts in planar structures,…) increases the impact of surfaces recombination and induces homogeneity in the photogenerated carrier concentrations. The investigation of their impacts on the device performances need to be addressed using full 3D coupled opto-electrical modeling. In this context, we have developed a new tool for full 3D opto-electrical simulation using the most advanced optical and electrical simulation techniques. We will present an overview of its simulation capabilities and the key issues that have been solved to make it fully operational and reliable. We will provide various examples of opto-electronic simulation of (i) nanostructured solar cells with localized contacts and (ii) nanowire solar cells. We will also show how opto-electronic simulation can be used to simulate light- and electron-beam induced current (LBIC/EBIC) experiments, targeting quantitative analysis of the passivation properties of surfaces.
Katz, Debra A; Kaplan, Marcia; Stromberg, Sarah E
2012-10-01
A national survey of candidates was conducted to identify motivations for pursuing psychoanalytic training, obstacles that prevent progression or completion, and candidates' ideas on how best to increase interest among potential trainees. In 2009-2010, 40 percent of candidates on the affiliate member e-mail list completed an anonymous web-based survey. Candidates strongly endorsed contact with a personal psychotherapist, psychoanalyst, or supervisor as the most important influence in discovering psychoanalysis and deciding to pursue training. They identified the total cost of analytic training as the greatest obstacle. This was followed by the cost of personal analysis, loss of income for low-fee cases, time away from family, and difficulty finding cases. To enhance training, local institutes should work to improve institute atmosphere and provide assistance with finding cases; national organizations should increase outreach activities and publicize psychoanalysis. Psychoanalytic institutes could recruit future candidates by working to increase personal contact with psychoanalysts, reducing the cost of training, improving institute atmosphere, assisting with case-finding, enhancing outreach activities, and widely publicizing psychoanalysis. Narrative comments from candidates and the implications of these findings regarding engagement of future trainees are discussed.
RUFFOLO, Bruno Bergamo; TOLEDO, Roberta dos Santos; MARTINS, Felippe Danyel Cardoso; BUGNI, Felipe Monteiro; da COSTA, Letícia; MARANA, Elizabete Regina Marangoni; NAVARRO, Italmar Teodorico; GARCIA, João Luis; SU, Chunlei; FREIRE, Roberta Lemos
2016-01-01
The role of rodents in the epidemiology of toxoplasmosis was investigated in Londrina, Paraná State, Brazil. One hundred and eighty-one Rattus rattus and one Mus musculus were caught in 37 places. Blood and tissues were collected and submitted to the indirect fluorescence antibody test (IFAT) and the bioassay. Serum samples from 61 contacting dogs were also collected. Sixteen rats (8.8%) were positive for Toxoplasma gondii, but just two of them were positive by serology and bioassay test. Antibodies were found in nine (4.9%) rats. Tissues of nine rats bioassayed were positive and four isolates were obtained. Restriction fragment length polymorphism (RFLP) analysis was performed using 12 markers (SAG1, SAG2, SAG2-alt, C22-8, C29-2, L358, PK1, BTUB, GRA6, SAG3, Apico, CS3). Genotyping revealed that the four strains isolated from this study have been isolated before in cats and chickens from Brazil. None of the isolates was identified like clonal archetypal T-types I, II, and III. The rats presented lower serologic Toxoplasma gondii prevalence (8.8%) compared to contacting dogs (70.5%). PMID:27074322
Presson, Nora; Beers, Sue R; Morrow, Lisa; Wagener, Lauren M; Bird, William A; Van Eman, Gina; Krishnaswamy, Deepa; Penderville, Joshua; Borrasso, Allison J; Benso, Steven; Puccio, Ava; Fissell, Catherine; Okonkwo, David O; Schneider, Walter
2015-09-01
To realize the potential value of tractography in traumatic brain injury (TBI), we must identify metrics that provide meaningful information about functional outcomes. The current study explores quantitative metrics describing the spatial properties of tractography from advanced diffusion imaging (High Definition Fiber Tracking, HDFT). In a small number of right-handed males from military TBI (N = 7) and civilian control (N = 6) samples, both tract homologue symmetry and tract spread (proportion of brain mask voxels contacted) differed for several tracts among civilian controls and extreme groups in the TBI sample (high scorers and low scorers) for verbal recall, serial reaction time, processing speed index, and trail-making. Notably, proportion of voxels contacted in the arcuate fasciculus distinguished high and low performers on the CVLT-II and PSI, potentially reflecting linguistic task demands, and GFA in the left corticospinal tract distinguished high and low performers in PSI and Trail Making Test Part A, potentially reflecting right hand motor response demands. The results suggest that, for advanced diffusion imaging, spatial properties of tractography may add analytic value to measures of tract anisotropy.
Amplitude quantification in contact-resonance-based voltage-modulated force spectroscopy
NASA Astrophysics Data System (ADS)
Bradler, Stephan; Schirmeisen, André; Roling, Bernhard
2017-08-01
Voltage-modulated force spectroscopy techniques, such as electrochemical strain microscopy and piezoresponse force microscopy, are powerful tools for characterizing electromechanical properties on the nanoscale. In order to correctly interpret the results, it is important to quantify the sample motion and to distinguish it from the electrostatic excitation of the cantilever resonance. Here, we use a detailed model to describe the cantilever dynamics in contact resonance measurements, and we compare the results with experimental values. We show how to estimate model parameters from experimental values and explain how they influence the sensitivity of the cantilever with respect to the excitation. We explain the origin of different crosstalk effects and how to identify them. We further show that different contributions to the measured signal can be distinguished by analyzing the correlation between the resonance frequency and the measured amplitude. We demonstrate this technique on two representative test samples: (i) ferroelectric periodically poled lithium niobate, and (ii) the Na+-ion conducting soda-lime float glass. We extend our analysis to higher cantilever bending modes and show that non-local electrostatic excitation is strongly reduced in higher bending modes due to the nodes in the lever shape. Based on our analyses, we present practical guidelines for quantitative imaging.
Domain structure of the ribozyme from eubacterial ribonuclease P.
Loria, A; Pan, T
1996-01-01
Large RNAs can be composed of discrete domains that fold independently. One such "folding domain" has been identified previously in the ribozyme from Bacillus subtilis ribonuclease P (denoted P RNA). This domain contains roughly one-third of all residues. Folding of an RNA construct consisting of the remaining two-thirds of B. subtilis P RNA was examined by Fe(II)-EDTA hydroxyl radical protection. This molecule folds into the proper higher-order structure under identical conditions as the full-length P RNA, suggesting the presence of a second folding domain in B. subtilis P RNA. Folding analysis of the Escherichia coli P RNA by hydroxyl radical protection shows that this P RNA is completely folded at 5-6 mM Mg2+. In order to analyze the structural organization of folding domains in E. coli P RNA, constructs were designed based on the domain structure of B. subtilis P RNA. Fe(II)-EDTA protection indicates that E. coli P RNA also contains two folding domains. Despite the significant differences at the secondary structure level, both P RNAs appear to converge structurally at the folding domain level. The pre-tRNA substrate, localized in previous studies, may bind across the folding domains with the acceptor stem/3'CCA contacting the domain including the active site and the T stem-loop contacting the other. Because all eubacterial P RNAs share considerable homology in secondary structure to either B. subtilis or E. coli P RNA, these results suggest that this domain structure may be applicable for most, if not all, eubacterial P RNAs. Identification of folding domains should be valuable in dissecting structure-function relationship of large RNAs. PMID:8718684
Atomic force microscopy as a tool for the investigation of living cells.
Morkvėnaitė-Vilkončienė, Inga; Ramanavičienė, Almira; Ramanavičius, Arūnas
2013-01-01
Atomic force microscopy is a valuable and useful tool for the imaging and investigation of living cells in their natural environment at high resolution. Procedures applied to living cell preparation before measurements should be adapted individually for different kinds of cells and for the desired measurement technique. Different ways of cell immobilization, such as chemical fixation on the surface, entrapment in the pores of a membrane, or growing them directly on glass cover slips or on plastic substrates, result in the distortion or appearance of artifacts in atomic force microscopy images. Cell fixation allows the multiple use of samples and storage for a prolonged period; it also increases the resolution of imaging. Different atomic force microscopy modes are used for the imaging and analysis of living cells. The contact mode is the best for cell imaging because of high resolution, but it is usually based on the following: (i) image formation at low interaction force, (ii) low scanning speed, and (iii) usage of "soft," low resolution cantilevers. The tapping mode allows a cell to behave like a very solid material, and destructive shear forces are minimized, but imaging in liquid is difficult. The force spectroscopy mode is used for measuring the mechanical properties of cells; however, obtained results strongly depend on the cell fixation method. In this paper, the application of 3 atomic force microscopy modes including (i) contact, (ii) tapping, and (iii) force spectroscopy for the investigation of cells is described. The possibilities of cell preparation for the measurements, imaging, and determination of mechanical properties of cells are provided. The applicability of atomic force microscopy to diagnostics and other biomedical purposes is discussed.
Rudolph, Michael J; Vance, David J; Cassidy, Michael S; Rong, Yinghui; Mantis, Nicholas J
2017-01-20
Ricin toxin is a heterodimer consisting of RTA, a ribosome-inactivating protein, and RTB, a lectin that facilitates receptor-mediated uptake into mammalian cells. In previous studies, we demonstrated that toxin-neutralizing antibodies target four spatially distinct hot spots on RTA, which we refer to as epitope clusters I-IV. In this report, we identified and characterized three single domain camelid antibodies (V H H) against cluster II. One of these V H Hs, V5E1, ranks as one of the most potent ricin-neutralizing antibodies described to date. We solved the X-ray crystal structures of each of the three V H Hs (E1, V1C7, and V5E1) in complex with RTA. V5E1 buries a total of 1,133 Å 2 of surface area on RTA and makes primary contacts with α-helix A (residues 18-32), α-helix F (182-194), as well as the F-G loop. V5E1, by virtue of complementarity determining region 3 (CDR3), may also engage with RTB and potentially interfere with the high affinity galactose-recognition element that plays a critical role in toxin attachment to cell surfaces and intracellular trafficking. The two other V H Hs, E1 and V1C7, bind epitopes adjacent to V5E1 but display only weak toxin neutralizing activity, thereby providing structural insights into specific residues within cluster II that may be critical contact points for toxin inactivation. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.
Gallardo, C; Soler, A; Nieto, R; Cano, C; Pelayo, V; Sánchez, M A; Pridotkas, G; Fernandez-Pinero, J; Briones, V; Arias, M
2017-02-01
An experimental infection was conducted to evaluate horizontal transmission, clinical, virological and humoral response induced in domestic pigs infected with African swine fever (ASF) genotype II virus circulating in 2014 into the European Union (EU). Ten naive pigs were placed in contact with eight pigs experimentally inoculated with the Lithuanian LT14/1490 ASF virus (ASFV) responsible for the first ASF case detected in wild boar in Lithuania in January 2014. Clinical examination and rectal temperature were recorded each day. Blood sampling from every animal was carried out twice weekly. Blood samples were examined for presence of ASF virus-specific antibodies and for determining the ASFV viral load. From the obtained results, it was concluded that the Lithuanian ASFV induced an acute disease which resulted in 94, 5% mortality. The disease was easily detected by real-time PCR prior to the onset of clinical signs and 33% of the animals seroconverted. All findings were in accordance with observations previously made in domestic pigs and wild boar when infected with ASF genotype II viruses characterized by a high virulence. One in-contact pig remained asymptomatic and survived the infection. The role of such animals in virus transmission would need further investigation. © 2015 Blackwell Verlag GmbH.
Duration of carriage and transmission of Yersinia enterocolitica biotype 4, serotype 0:3 in dogs.
Fenwick, S. G.; Madie, P.; Wilks, C. R.
1994-01-01
Human infections with pathogenic strains of Yersinia enterocolitica have been linked to contact with dogs excreting these microorganisms. This study examines the carriage and transmission of Y. enterocolitica biotype 4, serotype 03 in dogs. Fourteen 6-month-old cross-bred dogs were separated into 5 groups, 2 containing 4 dogs (I and II) and the others 2 dogs (III-V). Each of the 4 dogs in Group I and 2 of the dogs in Group II were inoculated orally with the test strain. Bacteriological examination of faecal samples showed that dogs can be readily infected and can carry the organism for up to 23 days. The two in-contact dogs in Group II started to shed the test organism after 5 days. Subsequent transfer of these dogs to Group III and those in Group III to Group IV showed that Y. enterocolitica biotype 4, serotype 03 can be readily transmitted between dogs. At no time did any of the dogs show clinical signs of infection. Group V served as a negative control for the trial. These findings suggest that dogs can carry Y. enterocolitica biotype 4, serotype 03 asymptomatically and hence might act as a potential source of infection for people. PMID:7995357
[Factor structure of symptoms in the Krakow Depression Inventory KID IO "B1" among 15-year-olds].
Bomba, Jacek; Modrzejewska, Renata; Beauvale, Andrzej
2011-01-01
The aim of the article is to partially verify the theoretical concept of depressive symptoms in adolescents, based on KID IO "B1", as well as to check the accuracy of the questionnaire. The KID results from an untreated sample population of 15-year-olds were statistically analysed. Of the 1118 KID IO "B1" questionnaires submitted, 594 (246 boys and 348 girls) underwent factor analysis, of which 297, i.e. half, gained a result higher than the diagnostic threshold for depression. In search of the presence of general factors, as well as to verify the principles used to categorise depressive symptoms according to clinical criteria, analysis of the factors using methods consisting of oblimin, quatrimax and varimax rotations was carried out separately and combined for both genders. The following new factors were distinguished for boys: I--lowered mood, and anxiety, II--self-destruction, III--apathy, cognitive disturbances, IV--somatic symptoms, V--somatisation, apathy, self-destruction, VI--boredom and avoidance of social contact, and for girls: I--lowered mood, lack of consideration for future repercussions, II--lowered drive, learning difficulties, cognitive and motivational disturbances, III--anxiety, IV--dysphoria with self-destruction, V--self-destruction, VI--eating pattern disturbances. Depression, as derived from factor analysis of the KID IO "B1" questionnaire positions, is heterogeneous. Theoretical division of symptom groups, relating to the specific scale in the questionnaire, was confirmed to a very small degree through the analysis of the factors. The list of factors in genders differs. The groups of symptoms appearing in both genders gained from analysis are different in boys and girls with one exception, which may partially result from the different factor overviews of depressive symptoms in both genders.